TWI524014B - High-speed bearings with lubricating oil and high-speed rolling bearings - Google Patents

Description

High-speed bearing lubricants and high-speed rolling bearings

The present invention relates to a high-speed bearing lubricating oil used for a rolling bearing for supporting a high-speed rotating shaft of a working machine spindle or the like, and a high-speed rolling bearing for sealing the lubricating oil inside.

The main shaft of the working machine must be rotated at a high speed to improve the machining efficiency, and the bearings are subjected to various lubrication techniques. Suitable for lubrication of high-speed rotating spindles, such as oil mist lubrication, oil and gas lubrication, spray lubrication, etc.

However, these lubrication methods require the installation equipment such as compressed air and the oil supply device, which causes an increase in the cost of purchasing the working machine and the running cost. In contrast, the lubrication of the lubricating oil is low due to the necessity of maintenance. It is the preferred method of lubrication. For example, in the case of a high-speed rolling bearing for supporting a rotating shaft rotating at 2000 to 8000 rpm or higher, it includes a bevel ball bearing for supporting a spindle of a working machine, a cylindrical roller bearing, and the like.

The bevel ball bearing 51 shown in Fig. 14 can load the axial load in one direction in addition to the load of the load, and is connected by a straight line connecting the contact points of the steel ball 54 and the inner ring 52 and the outer ring 53 with respect to the radial direction. It has an included angle (contact angle) α. Lubricating oil is sealed in the bearing space formed by the inner ring 52 and the outer ring 53 and the steel ball 54.

High-speed use as a bevel ball bearing, cylindrical roller bearing, etc. The lubricant used for the rolling bearing is preferably a lubricating oil that does not require maintenance of oil supply and the like, and adjusts the consistency to a level that does not pollute the surrounding environment.

The lubrication characteristics and problems required for the lubricating oil used for the high-speed rolling bearing such as the rolling bearing for the spindle can be arranged as follows.

(a) In order to maximize the lubrication life of long-life rolling bearings, as explained in (i) to (iii) below, it must be met: lubricants (lubricants or their base oils) are not easily leaked from the rolling bearings, and the heat resistance of the lubricating oil is excellent. It can form the requirements of the thickness of the oil film required for lubrication.

(i) When the rolling bearing is running at a high speed, the centrifugal force causes the lubricating oil in the rolling bearing to flow to the outside of the bearing, or the base oil in the lubricating oil is separated and flowed out, and is not easily left in the vicinity of the raceway surface to be highly lubricated, so that lubrication is liable to occur. bad. In order to prevent such a situation from occurring, a countermeasure is to mount a plate member such as a sealing plate on a rolling bearing. However, depending on the configuration of the bearing, it may occur that the installation cannot be performed, and even if the sealing member is installed, there is a possibility that the lubricant or the lubricating oil cannot be completely sealed.

In the case of a non-high-speed rolling bearing, the excess lubricating oil extruded from the friction portion due to the movement of the rotating body or the retainer is recirculated to the inside of the bearing to a certain extent under the condition of rotation to be relubricated. However, in the rolling bearing for the shaft supporting such as a working machine that rotates at a high speed, since the wind pressure generated inside the bearing hinders the progress of the recirculation, it is difficult to supply the lubricating oil to the race portion, and lubrication failure is likely to occur. Therefore, in a rolling bearing that rotates at a high speed, only a small amount of lubricating oil is used for lubrication, so the nature of the lubricating oil is particularly important. Lubricating oils used in high-speed rolling bearings must be required to maintain lubrication even with a small amount of lubricating oil.

(ii) When the operating conditions are increased, the rolling surface of the bearing is locally heated to form a high temperature. In this case, the lubricating oil having poor heat resistance is thermally deteriorated, and the life of the lubricating oil is remarkably shortened. In response to this problem, attempts have been made to use a heat-resistant thickener or base oil, or to add an oxidation preventive agent, but these attempts have failed to achieve satisfactory durability improvement.

(iii) A conventional lubricating oil that improves lubricity (oil film thickness). If the viscosity of the base oil becomes high, the shear frictional resistance becomes large, causing an increase in torque and an increase in calorific value. In order to suppress these phenomena, the base oil is used. Viscosity is reduced. Therefore, the lubricating oil film which becomes a low viscosity due to the temperature rise accompanying the high-speed operation becomes thin, and sliding wear may occur.

(b) An existing high-speed bearing lubricating oil having low torque (temperature rise suppression), although the base oil viscosity can be reduced as described above, when the bearing rotates at a high speed, the temperature rise causes a significant decrease in viscosity. It is impossible to form an oil film of the thickness required for lubrication.

(c) For low-vibration lubricating oils, depending on the type of thickener, the vibration of the bearing may become large. That is, the thickener contained therein forms a large and hard agglomerated lubricating oil, and the vibration of the lubricated rolling bearing becomes large.

Such a conventional lubricating oil cannot be used in the case of a high-speed rolling bearing, and cannot meet the requirements of physical properties such as long life of the bearing, low torque, and low vibration. As a countermeasure against this, a lubricating oil containing a urea compound has been proposed (see Patent Document 1 to Patent Document 3), but the amount of oil consumption is increased, and it is not sufficient to obtain higher-speed performance.

For example, the lubricating oil composition disclosed in Patent Document 3 contains a base oil having a dynamic viscosity of 40 mm ² /sec or more and 40 mm ² /sec or less at 40 ° C, and the content is 9 mass% or more and 14 mass% of the entire lubricating oil composition. The thickening agent of the following diurea compound has a mixed consistency of 220 or more and 320 or less.

However, in the above lubricating oil composition, it is also difficult to reduce the blending amount of the thickener to reduce the amount of lubricating oil enclosed, and it is not sufficient to correspond to the high-speed rotation of the bearing, and it is necessary to achieve compaction of the working machine and operation cost. It will be difficult to lower.

In addition, in recent years, the use of the rolling bearing is becoming more and more severe, and the rolling bearing for the spindle used for high-speed rotation in which the product of the pitch diameter dm (mm) and the number of revolutions N (rpm) (dmN value) is 1.7 million or more is used. It has also become more and more. With such a high speed of rotation of the bearing, it is quite difficult for the existing lubricating oil to completely conform to the required performance of the bearing.

Patent Document 1: Japanese Laid-Open Patent Publication No. 2000-169872 Patent Document 2: Japanese Patent Laid-Open Publication No. 2003-83341 Patent Document 3: Japanese Laid-Open Patent Publication No. 2006-29473

The present invention has been made in view of such circumstances, and an object thereof is to provide a lubricating oil for a high-speed bearing which can be used for a rolling bearing, which can correspond to, for example, a pitch diameter dm (mm) even with a small amount of lubricating oil. And the product of the number of revolutions N (rpm) (dmN value) is 1.7 million or more high-speed rotation, and it is possible to reduce the compaction of the machine tool and the operation cost, and to provide a high-speed use for sealing the lubricating oil inside. Rolling bearings.

The lubricating oil for high speed bearing of the present invention is used in the use of a urea compound In the urea-based lubricating oil which is a thickener, a lubricating oil for a high-speed bearing which is composed of a non-urea-based lubricating oil which does not contain the urea-based compound, is characterized in that the urea-based compound is a polyisocyanate component and a monoamine component. The monoamine component is a monoamine component containing 50 mol% or more of at least one monoamine selected from the group consisting of an aliphatic monoamine and an alicyclic monoamine with respect to the entire monoamine.

Further, the thickener of the non-urea-based lubricating oil is a metal soap or a Na-p- phthalate, and the blending ratio of the non-urea-based lubricating oil is 10 to 40% by weight.

The above metal soap is a ruthenium metal soap or a complex amide metal soap having a guanamine bond in the molecule. Further, the above-described amide metal soap or complex amide metal soap is sodium, calcium, aluminum, zinc or cerium as a metal species.

The dynamic viscosity of the urea-based lubricating oil and the base oil of the non-urea-based lubricating oil is 15 to 40 mm ² /sec. The base oil of the urea-based lubricating oil is at least one selected from the group consisting of synthetic hydrocarbon oils, ester oils, and alkyl diphenyl ether oils.

The high-speed rolling bearing of the present invention is a high-speed rolling bearing for supporting a shaft that rotates at a high speed, and is characterized in that the rolling bearing includes an inner ring and an outer ring, and a plurality of rotating bodies interposed between the inner ring and the outer ring. a retaining member for holding the rotor, a sealing member for covering an opening between the inner ring and the outer ring; and lubricating oil surrounding the rotating body, the lubricating oil using the high speed bearing of the present invention Use lubricating oil.

Further, at least one of the surface of the raceway surface selected from the inner ring, the surface of the raceway surface of the outer ring, and the surface of the rotor is subjected to pit processing.

Further, the above-mentioned pit processing is bead processing, and each of the pits is formed by the processing. The pit on the surface has a depth of 0.1 to 10 μm from the surface.

Further, at least one of an outer diameter surface selected from the inner ring, an inner diameter surface of the outer ring, and a surface of the rotor is formed to form a film.

Further, the above-mentioned film is a film formed by metal plating treatment or phosphoric acid film treatment.

Further, the holder has a concave portion on the inner surface of the pocket, and at least the edge portion of the concave portion is chamfered.

Further, the concave portion is an oil storage portion or a relief portion.

Further, the above holder is a resin holder.

Further, the resin used in the above retainer is a polyamide (hereinafter referred to as PA) resin, a phenol resin or a polyetheretherketone (hereinafter referred to as PEEK) resin.

Further, at least a part of the inner surface of the bearing that is in contact with the lubricating oil forms a water-repellent oil-repellent coating.

Further, the water-repellent oil-repellent coating film is formed by: (1) a part of the inner side surface of the bearing of the sealing member, (2) an inner diameter surface other than the rail surface of the outer ring, and a bearing inner side surface of the sealing member, (3) at least one of an outer diameter surface of the inner ring other than the raceway surface and a bearing inner side surface of the sealing member, and (4) a surface of the retainer other than the contact surface with the rotor.

Further, the water-repellent oil-repellent film is formed using a lanthanoid compound or a fluorine-based compound.

Further, the above oxime compound is a siloxane, and the fluorine compound is a fluoroalkyl decane.

The above high speed rolling bearing is used to support the spindle of the working machine. Bearings.

Further, the above high speed rolling bearing is a bevel ball bearing or a cylindrical roller bearing.

In the lubricating oil for high-speed bearing of the present invention, a urea-based lubricating oil using a predetermined urea-based compound as a thickener is blended with a non-urea-based lubricating oil containing no such urea-based compound, and even a small amount of lubricating oil is enclosed. It is still possible to ensure the load-bearing resistance of the rolling bearing in which the lubricating oil is sealed inside, and is excellent in the ability to supply oil to the raceway surface under high-speed rotation.

In particular, the monoamine component constituting the urea-based compound contains at least one monoamine selected from the group consisting of an aliphatic monoamine and an alicyclic monoamine with respect to 50 mol% or more of the entire monoamine, and the thickener is not easily The shearing force at high speed is broken, and the capillary phenomenon of the thickener is used to stably supply the oil of the lubricating oil to the raceway surface.

In the high-speed rolling bearing of the present invention, since the lubricating oil is sealed inside, the lubricating oil does not flow out of the bearing under the condition of high centrifugal force, and the amount of oil required for bearing lubrication can be stably supplied for a long period of time, and the high-speed sliding The track surface of the joint can form an oil film of the required thickness for lubrication. Therefore, the bearing durability life under high-speed rotation can be prolonged.

Since at least one of the raceway surface of the inner ring of the bearing, the raceway surface of the outer ring, and the surface of the rotor forms a plurality of dimples of the minute recesses, the contact surface of the orbital ring and the rotor can be raised. The oil film forming ability can obviously enhance the prolongation effect of the lubricating oil life under the state of the trace oil supply.

Due to the outer diameter surface selected from the inner ring of the bearing, the inner diameter surface of the outer ring of the bearing, At least one of the surfaces of the rotating body is formed by metal plating treatment or phosphoric acid film treatment to form a film, which can greatly improve the lubricating ability of the contact surface in a state of supply of a small amount of oil, and can significantly improve the lubricating oil in a state of supply of a small amount of oil. The effect of extending the life. Even if it is excluded from the raceway portion and the lubricating oil deposited on the periphery is difficult to supply oil, the effect of the coating is used to facilitate the diffusion of the base oil and to improve the wettability, thereby prolonging the life of the lubricating oil (burning).

Since the inner surface of the bag hole portion of the retainer has a concave portion, the lubricating oil held in the concave portion is supplied to the contact portion between the rotating body and the inner surface of the bag hole portion during the operation of the bearing, and the lubricating state of the contact portion can be maintained good. Further, since at least the edge portion of the concave portion is chamfered, the lubricating oil adhering to the surface of the rotating body is not easily scraped off by the edge portion, and the lubricating oil is easily obtained at a necessary portion of the bag hole portion. As a result, the bearing durability life under high-speed rotation can be greatly extended.

Since at least a part of the inner surface of the bearing that is in contact with the lubricating oil forms a water-repellent oil-repellent film, even in a state of high centrifugal force, the oil of the lubricating oil can be moved to the raceway surface without flowing out of the bearing. Moreover, the amount of oil required for bearing lubrication can be stably supplied for a long period of time, and the oil film of the thickness required for lubrication can be formed for the track surface of the high-speed sliding joint. Therefore, the bearing durability life under high-speed rotation can be prolonged.

The high-speed rolling bearing of the present invention is not particularly limited in structure, and is, for example, a bevel ball bearing shown in Fig. 1. Fig. 1 is a longitudinal sectional view of a bevel ball bearing in which lubricating oil is sealed.

As shown in FIG. 1, the bevel ball bearing 1 holds a bearing space formed by the rotor 4 between the inner ring 2 and the outer ring 3 by a retainer 5, and is fixed to the locking groove (outer The sealing member 6 of the inner circumferential surface of the ring 3 is sealed to form a bevel ball bearing. At least the lubricating oil is sealed around the rotor 4, and a circumferential groove-shaped lubricating oil bag hole 7 is formed on the inner diameter surface of the outer ring 3 to physically prevent leakage of lubricating oil. A straight line connected by the contact points of the rotor 4 and the inner ring 2 and the outer ring 3 has a contact angle β with respect to the radial direction, which can load the radial load and the axial load in one direction. The rotor 4 can be made of ceramic such as tantalum nitride or tantalum carbide. In the present invention, the bearing space formed by the inner ring 2, the outer ring 3, and the rotor 4 is sealed with the lubricating oil 8 for a high-speed bearing of the present invention to be described later.

In another embodiment of the high-speed rolling bearing according to the present invention, at least one of the surface of the raceway surface selected from the inner ring of Fig. 1, the surface of the raceway surface of the outer ring, and the surface of the rotor is subjected to pit processing. Angular ball bearings. By the pit processing, pits of minute recesses are formed on the respective surfaces.

The pit processing may be a method in which a pit can be formed on the raceway surface of the orbital ring (inner ring and outer ring) formed of the bearing steel or the surface of the rotor, and a known method can be used. Specifically, bead blasting, cylinder barrel grinding, laser irradiation, etching, mold transfer, and the like can be employed. Among them, based on the viewpoint of cost and convenience, it is preferable to use the bead hit method.

In the present invention, in order to form a pit on the raceway surface of the orbital ring and the surface of the rotor by the bead hit, for example, the bead material having a particle diameter of 30 to 300 μm is directed toward the raceway surface of the orbital ring to be 0.01. A pressure of ~1 MPa is sprayed for 1 to 60 seconds, thereby forming pits.

As the bead material, any hole may be formed in the orbital ring or the rotating body formed of the bearing steel. Specifically, alumina, strontium carbide, glass beads, and the like are mentioned, and among them, alumina which is excellent in economical efficiency and workability is preferable.

The pit formed on the raceway surface of the orbital ring and the surface of the rotor by the above-mentioned pit processing should have a depth of 0.1 to 10 μm, more preferably 1 to 5 μm from the surface of the raceway surface or the surface of the rotor. . When the thickness is less than 0.1 μm, the pit effect becomes small and it is not good. If it is 5 μm or more, the noise of the bearing becomes large, which is not preferable.

The pit formed on the surface of the raceway surface of the orbital ring and the surface of the rotor is preferably periodically formed in order to stabilize the thickness of the oil film. Preferably, the dimple extends in a direction orthogonal to the rolling sliding direction. Thereby, the lubricating oil which is removed from the race portion and accumulated in the periphery can supply the oil more smoothly.

In another embodiment of the high-speed rolling bearing according to the present invention, at least one of the outer diameter surface 2a of the inner ring 2 of the first drawing, the inner diameter surface 3a of the outer ring 3, and the surface of the rotor 4 is formed into a film. Angular ball bearings. These films can be formed by performing a predetermined surface treatment on each surface. The surface treatment is preferably such that the rotational friction can be reduced and it is not easily peeled off. In the surface treatment which is excellent in lubricity and is not easily peeled off, metal plating treatment or phosphoric acid coating treatment is preferred.

As the metal plating treatment, a method such as electroplating or electroless plating can be used. The metal to be used is preferably a metal which is soft and has excellent adhesion to a base material (bearing steel) such as Cu, Ag, Ni, Zn or Sn.

The phosphoric acid film is treated, for example, by immersing an orbital ring or the like in a phosphate triester solution to form a metal phosphate film on the surface thereof. The phosphoric acid triester is an organic phosphoric acid compound represented by (RO) ₃ P=O (wherein R represents an aryl group, an aliphatic hydrocarbon group or an alicyclic hydrocarbon group), and a plasticizer of a commercially available industrial material or the like can be used. Examples of the phosphate triester include: tricresyl phosphate (CH ₃ C ₆ H ₄ O) ₃ PO, triphenyl phosphate (C ₆ H ₅ O) ₃ PO, and tributyl phosphate (C ₄ H ₉ O) _{3 .} PO and so on. The above-mentioned phosphate triester may be diluted with an organic solvent and used as necessary in terms of handling. When the phosphate triester and the bearing steel are reacted to form a metal salt film on the surface thereof, the reaction speed may be increased while heating, for example, by immersing at about 60 ° C for 1 to 2 hours to form a sufficient thickness. Membrane.

By preliminarily mixing the phosphate triester in the lubricating oil to be described later, the metal phosphate film can be formed on the contact surface between the rotor and the inner and outer rings by the temperature rise due to the operation of the bearing. The advantage of this method is that the wear of the film can be compensated at any time.

In another embodiment of the high-speed rolling bearing according to the present invention, for example, the rotor body is held by the pocket portion of the retainer, and the inner surface of the pocket portion has a concave portion, and at least the edge portion of the concave portion is chamfered. Angled ball bearings. Fig. 2 is a longitudinal sectional view showing such an oblique ball bearing. Fig. 3 is a perspective view of the machined retainer 15 used in the bevel ball bearing 11.

The bevel ball bearing 11 is a bearing space formed by holding the rotor 14 between the inner ring 12 and the outer ring 13 by the retainer 15 as shown in Fig. 2, and is fixed to the locking groove (provided outside) Seal of the inner peripheral surface of the ring 13 The angled ball bearing is formed by sealing the member 16. In the bearing space formed by the inner ring 12, the outer ring 13, and the rotor 14, the high-speed bearing lubricating oil 17 of the present invention will be described later. A straight line connected by the contact points of the rotor 14 and the inner ring 12 and the outer ring 13 has a contact angle β with respect to the radial direction, which can load the radial load and the axial load in one direction. The rotor 14 may be made of ceramic such as tantalum nitride or tantalum carbide.

As shown in Fig. 3, a concave oil reservoir 15c and a relief portion 15b are provided in the pocket inner surface 15a of the machined retainer 15. Further, the edge portion 15d of the concave portion which is formed by the concave portions is subjected to chamfering. Only one of the oil reservoir 15c and the relief portion 15b may be provided. In addition to the edge of the recess, it is also possible to perform chamfering on all edges of the retainer that may be in contact with the rotor.

In the same embodiment, for example, the rotor body is held by the pocket portion of the retainer, and the inner surface of the pocket portion has a concave portion, and at least the edge portion of the concave portion is chamfered, thereby forming a deep groove ball bearing. Fig. 4 is a longitudinal sectional view showing the deep groove ball bearing in which the lubricating oil is sealed. Fig. 5 is a perspective view of a crown holder 25 used in a deep groove ball bearing.

The deep groove ball bearing 21, as shown in Fig. 4, holds the bearing space formed by the rotor 24 between the inner ring 22 and the outer ring 23 by the retainer 25, and is fixed to the locking groove (provided outside) The inner circumferential surface of the ring 23 is sealed by a sealing member 26 to form a deep groove ball bearing. In the bearing space formed by the inner ring 22, the outer ring 23, and the rotor 24, the high-speed bearing lubricating oil 27 of the present invention will be described later. The rotor 24 may be made of ceramic such as tantalum nitride or tantalum carbide.

As shown in Fig. 5, a concave cross-sectional side oil reservoir portion 25b and a bottom surface side oil reservoir portion 25c are provided in the pocket hole inner surface 25a of the retainer 25, and the edge portion of the recess portion which is formed by the recess portions is provided. 25d implementation of the chamfering process. In addition to the edge of the recess, it is also possible to perform chamfering on all edges of the retainer that may be in contact with the rotor.

The holder assembled in the high-speed rolling bearing of the present invention is preferably made of a resin. The resin retainer can reduce the weight of the bearing and reduce the influence of the centrifugal force under high-speed rotation. Further, it is possible to suppress frictional heat generation of the sliding portions of the rotating body and the retainer.

As the resin holder, a resin having heat resistance and oil resistance is preferably used. For example, PA resin, polyethylene resin, polyacetal resin, polyethylene terephthalate resin, polybutylene terephthalate resin, polycarbonate resin, polyphenylene sulfide resin, polyether can be used. Anthracene resin, phenol resin, polyether quinone imide resin, polyamidoximine resin, PEEK resin, thermoplastic polyimide resin, and the like. These can be used individually or in combination of 2 or more types.

Among them, from the viewpoints of light weight, excellent affinity with oil, and excellent mechanical stability, PA resin such as PA46 resin, PA66 resin, PA9T resin or the like which is reinforced with glass fiber or the like is preferred. Pake resin such as Bakelite), PEEK resin.

In another embodiment of the high-speed rolling bearing according to the present invention, for example, as shown in FIGS. 6 to 9, the bevel ball bearing in which the water-repellent oil-repellent film is formed on at least a part of the inner surface of the bearing that is in contact with the sealed lubricating oil is used.

Even if the amount of lubricating oil is small, it can fully correspond to high-speed rotation, and it is possible to achieve a reduction in work machine and a reduction in operating expenses. As a result of intensive investigation, it has been found that a water-repellent oil-repellent film is provided on at least a part of the inner surface of the bearing of the member of the high-speed rolling bearing, and a predetermined lubricating oil is sealed to obtain a rolling bearing having a long life at a high speed.

At least a part of the inner surface of the bearing that is in contact with the lubricant (the lubricating oil sealed in the bearing, etc.) forms a water-repellent oil-repellent film, and the surface tension of the water-repellent oil-repellent film prevents the lubricant from remaining on the surface of the film and moves it actively. . Therefore, a predetermined lubricant that is actively moved will continue to have a sliding surface such as a rotating surface and a raceway surface, and the durability of the lubricating action can be improved to obtain a long-life rolling bearing.

Fig. 6 is a cross-sectional view showing an example of a position at which a water-repellent oil-repellent film of a bevel ball bearing is formed. The water-repellent oil-repellent film may be formed on at least a part of the inner surface of the bearing that is in contact with the lubricating oil 37, and is preferably formed outside the sliding surface. The sliding surface herein includes an inner ring raceway surface 32a, an outer ring raceway surface 33a, a contact surface of the retainer 35 with the rotor 34, a surface of the rotor 34, and the like.

The bevel ball bearing 31 of FIG. 6 holds the bearing space formed by the rotor 34 between the inner ring 32 and the outer ring 33 by the retainer 35, and is fixed to the locking groove (provided in the outer ring 33). The sealing member 36 of the circumferential surface is sealed, and a water-repellent oil-repellent film 38a is formed in a part of the inner side surface of the bearing of the sealing member 36. In the bearing space formed by the inner ring 32, the outer ring 33, and the rotor 34, the high-speed bearing lubricating oil 37 of the present invention described later is sealed.

A straight line connected by the contact points of the rotating body 34 and the inner ring 32 and the outer ring 33 has a contact angle β with respect to the radial direction, which can load the load and the load The axle load of the direction. Further, the rotating body 34 may be made of ceramic such as tantalum nitride or tantalum carbide.

7 to 9 are cross-sectional views showing other examples of the positions at which the water-repellent oil-repellent film is formed. 7 is an inner diameter surface other than the track surface 33a of the outer ring, and a water-repellent oil-repellent film 38b is formed on the inner side surface of the bearing of the sealing member 36. FIG. 8 is a view other than the track surface 32a of the inner ring. The outer diameter surface and the inner side surface of the bearing of the seal member 36 form a water-repellent oil-repellent film 38c. Fig. 9 is a water-repellent oil-repellent film 38d formed on the surface of the retainer 35 except for the contact surface with the rotor 34. The structures other than the water-repellent oil-repellent film in Figs. 7 to 9 are the same as those in Fig. 6.

In the sixth to ninth drawings, the positions at which the water-repellent oil-repellent coating film is formed are individually displayed, but these forming positions may be used alone or in combination of two or more.

Further, in the same embodiment, for example, FIGS. 10 to 13 show a deep groove ball bearing in which at least a part of the inner surface of the bearing which is in contact with the sealed lubricating oil forms a water-repellent oil-repellent film.

Fig. 10 is a cross-sectional view showing an example of a position at which a water-repellent oil-repellent film of a deep groove ball bearing is formed. The water-repellent oil-repellent film may be formed on at least a part of the inner surface of the bearing that is in contact with the lubricating oil 47, and is preferably formed outside the sliding surface. The sliding surface herein includes an inner ring raceway surface 42a, an outer ring raceway surface 43a, a contact surface of the retainer 45 with the rotor 44, a surface of the rotor 44, and the like.

The deep groove ball bearing 41 of Fig. 10 holds the bearing space formed by the rotating body 44 with the retainer 45 between the inner ring 42 and the outer ring 43. The sealing member 46 fixed to the locking groove (the inner circumferential surface of the outer ring 43) is sealed, and a water-repellent oil-repellent coating 48a is formed in a part of the bearing inner side surface of the sealing member 46. In the bearing space formed by the inner ring 42, the outer ring 43, and the rotor 44, the high-speed bearing lubricating oil 47 of the present invention will be described later. Further, the rotating body 44 may be made of ceramic such as tantalum nitride or tantalum carbide.

11 to 13 are cross-sectional views showing other examples of the positions at which the water-repellent oil-repellent film is formed. 11 is an inner diameter surface other than the track surface 43a of the outer ring, and a water-repellent oil-repellent film 48b is formed on the inner side surface of the bearing of the sealing member 46. FIG. 12 is a view other than the track surface 42a of the inner ring. The outer diameter surface and the inner side surface of the bearing of the sealing member 46 form a water-repellent oil-repellent film 48c. Fig. 13 is a water-repellent oil-repellent film 48d formed on the surface of the retainer 45 except for the contact surface with the rotor 44. In the drawings 11 to 13, the structures other than the water-repellent oil-repellent film are the same as those in the tenth figure.

In the figures 10 to 13, the positions at which the water-repellent oil-repellent coating film is formed are individually displayed, but these forming positions may be used alone or in combination of two or more.

By forming the water-repellent oil-repellent coatings 38a to 38d and 48a to 48d on the inner surface of the bearing as shown in Figs. 6 to 13 , the surface tension of the oil-repellent coatings 38a to 38d and 48a to 48d can be avoided. The sealed lubricating oils 37, 47 remain on the surface of the film to be movable. Therefore, for example, the inner ring raceway faces 32a, 42a, the outer ring raceway faces 33a, 43a, the contact faces of the retainers 35, 45 and the rotors 34, 44, and the rotator are not formed in the films 38a to 38d, 48a to 48d. 34, 44 surface, etc. The lubricating oils 37 and 47 are continuously supplied, thereby enhancing the durability of the lubricating action and becoming a long-life rolling bearing.

Further, by forming the water-repellent oil-repellent film on the outside of the sliding surface, peeling of the film due to the sliding can be avoided.

The material used for forming the water-repellent oil-repellent film may be a hydrazine-based or fluorine-based water-repellent oil-repellent agent, and is not particularly limited. The water-repellent oil-repellent film is preferably a film composed of a hydrazine-based water-repellent agent such as decane-oxygen or a water-repellent oil-repellent film formed using a fluoroalkyl decane.

For commercial products, for example, it is: Mektron: Nukusgard ST-420, Daikin Industries: Unidayne, Shin-Etsu Chemical: Perfluoroalkyl decane KBM7803, etc. .

In the above embodiment of the high-speed rolling bearing according to the present invention, the water-repellent oil-repellent film may be formed on the inner surface of the bearing that is in contact with the lubricating oil, and the method of forming the film is not particularly limited. In order to form a water-repellent oil-repellent film on the inner surface of the bearing that is in contact with the lubricating oil, the rolling bearing may be immersed in a dispersion of a hydrazine-based water-repellent oil agent such as decane oxygen, and dried to form a water-repellent oil-repellent film. Further, dry plating such as vacuum evaporation, physical vapor deposition (PVD), chemical vapor deposition (CVD), ion plating, or electroplating may be employed.

It is also possible to form a water-repellent oil-repellent film by applying a commercially available water- and water-repellent agent to the inner surface of the bearing which is in contact with the lubricating oil. Among them, a method of immersing a rolling bearing in a water-repellent oil-dispersing agent dispersion liquid is preferable because it is not necessary to perform water-repellent oil-repellent treatment for each component, and processing cost is favorable.

The high-speed rolling bearing of the present invention is preferably a lubricating oil which is sealed in a volume of the bearing volume of 1% by volume or more and 10% by volume or less. If it is less than 1% by volume, the amount of lubricating oil required for lubrication is insufficient and it is prone to depletion. When the volume is 10% by volume or more, the stirring torque is increased, and the heat is increased, which not only does not extend the lubrication life, but also increases the cost and is not good for the environment.

In addition to the bevel ball bearing and the deep groove ball bearing shown in each of the above embodiments, the high speed rolling bearing of the present invention can also be used with a cylindrical roller bearing, a tapered roller bearing, a self-aligning roller bearing, and a needle roller. Bearings, thrust cylindrical roller bearings, thrust tapered roller bearings, thrust needle roller bearings, thrust self-aligning roller bearings, etc. Among them, it is preferable to use a bevel ball bearing or a cylindrical roller bearing from the viewpoint of both the rotation accuracy and the load-bearing performance of the high-speed rotation.

The high-speed rolling bearing of the present invention is characterized in that the lubricating oil for high-speed bearing used is a urea-based lubricating oil using a urea-based compound as a thickener, and is blended without the urea-based compound. Non-urea lubricating oil.

The base oil of the urea-based lubricating oil and the non-urea-based lubricating oil of the present invention can be a lubricating oil having a dynamic viscosity at 40 ° C (hereinafter referred to as dynamic viscosity) of 15 to 40 mm ² /sec. It is preferably a lubricating oil having a dynamic viscosity of 18 to 30 mm ² /sec. In the case where the dynamic viscosity is less than 15 mm ² /sec, the viscosity is too low to obtain sufficient load resistance. Further, in the case where the dynamic viscosity exceeds 40 mm ² /sec, the amount of oil supplied to the raceway surface under high-speed rotation is insufficient, and the bearing life is terminated early.

The type of the base oil of the urea-based lubricating oil is preferably a synthetic hydrocarbon oil, an ester oil, an alkyl diphenyl ether oil, or a mixed oil thereof.

Further preferably, the dynamic viscosity of each of the synthetic hydrocarbon oil, the ester oil, and the alkyl diphenyl ether oil is 15 to 40 mm ² /sec. If it is in this range, even if it is a mixed oil, the dynamic viscosity can be ensured in the range of 15 to 40 mm ² /sec.

In the case of being a mixed oil, it is preferred to use a synthetic hydrocarbon oil as an essential component, and it is preferable that the weight ratio of the synthetic hydrocarbon oil is equal to or more than the same amount of the ester oil or the alkyl diphenyl ether oil.

For the synthesis of hydrocarbon oils, for example, poly-α-olefins such as normal paraffin, isoparaffin, polybutene, polyisobutylene, 1-decene oligomer, 1-decene and ethylene co-oligomer, and the like and many more.

In the case of ester oils, for example, include: dibutyl sebacate, di-2-ethylhexyl sebacate, dioctyl adipate, diisodecyl adipate, ditridecane Adipic acid ester, ditridecyl ester, methyl. a diester oil such as acetyl phthalic acid ester; an aromatic ester oil such as trioctyl trimellitate, tridecyl trimellitate or tetraoctyl trimellitate; Polyol ester oils such as propane octanoate, trimethylolpropane decanoate, pentaerythritol-2-ethylhexanoate, pentaerythritol phthalate, carbonate oil, and the like.

The alkyl diphenyl ether oil includes, for example, a monoalkyl diphenyl ether, a dialkyl diphenyl ether, a polyalkyl diphenyl ether, and the like.

The urea-based compound (urea thickener) is obtained by reacting a polyisocyanate component and a monoamine component.

The polyisocyanate component includes, for example, p-phenylene diisocyanate, toluene diisocyanate, diphenyl diisocyanate, diphenylmethane diisocyanate, octadecyl diisocyanate, decyl diisocyanate, hexane diisocyanate, and the like. Among them, aromatic diisocyanate is preferred.

Further, a polyisocyanate obtained by reacting a diamine and a molar excess of diisocyanate can also be used. Examples of the diamine include ethylenediamine, propylenediamine, butanediamine, hexamethylenediamine, octanediamine, phenylenediamine, toluenediamine, xylenediamine, diaminodiphenylmethane, and the like.

The monoamine component contains 50 mol% or more of at least one monoamine selected from the group consisting of an aliphatic monoamine and an alicyclic monoamine, and preferably contains 80 mol% or more. By containing 50 mol% or more, the thickener is not easily broken by shearing force at a high speed, and the capillary phenomenon of the thickener fiber can stably supply the oil in the lubricant to the raceway surface.

The monoamine other than the aliphatic monoamine and the alicyclic monoamine is, for example, an aromatic monoamine.

As the aliphatic monoamine, there may be mentioned hexylamine, octylamine, dodecylamine, hexadecylamine, stearylamine, stearylamine, oleylamine and the like, among which octadecylamine is preferred.

In the case of an alicyclic monoamine, for example, cyclohexylamine or the like.

As the aromatic amine, aniline, p-toluidine, etc. may be mentioned, and among them, p-toluidine is preferred.

The amount of the urea-based thickener is preferably from 3 to 20% by weight, more preferably from 5 to 15% by weight, based on the total amount of the urea-based lubricating oil. When the blending amount is less than 3% by weight, the base oil retaining ability is insufficient, and particularly in the initial stage of the rotation, a large amount of oil is temporarily separated to cause leakage of the lubricating oil, which results in a shortened bearing durability life. Further, when the blending amount exceeds 20% by weight, the relative content of the base oil becomes small, the oil supply property is deteriorated, and the insufficient lubrication is caused early, and the bearing durability life is shortened in the same manner.

In addition to the synthetic oil, the ester oil, the alkyl diphenyl ether oil, or the like, which is used as the base oil of the urea-based lubricating oil, the base oil of the non-urea lubricating oil can be used in addition to the mixed oil of the synthetic hydrocarbon oil, the ester oil, the alkyl diphenyl ether oil, or the like. Oil, fluoro oil, fluorenone oil, etc. are used singly or in combination.

As the mineral oil, a lubricating oil derived from crude oil can be obtained by vacuum distillation, solvent deasphalting, solvent extraction, hydrogenation decomposition, solvent dewaxing, sulfuric acid washing, white clay purification, hydrorefining, and the like.

The fluorine oil may be a compound capable of substituting a hydrogen atom of the aliphatic hydrocarbon polyether with a fluorine atom, and for example, a perfluoropolyether oil can be used. The perfluoropolyether oil includes, for example, a perfluoropolyether having a side chain such as Fomblin Y (trade name of Montedison), a Krytox (trade name of DuPont), and the like, and Fomblin Z (product of the company) Name), a linear perfluoropolyether such as Fomblin M (trade name of Monti Dyson), and a product of Jemmnan (Daikin company name).

As the fluorenone oil, a so-called denatured oxime oil such as dimethyl fluorenone oil or methyl phenyl fluorenone oil, or a so-called denatured oxime such as an alkyl-modified fluorenone oil or an aralkyl-modified fluorenone oil can be used. Ketone oil.

As the thickener (non-urea thickener) of the above-mentioned non-urea-based lubricating oil, a metal soap excellent in oil separation property, Na-p- phthalate, a polytetrafluoroethylene resin, or the like can be used.

The metal soap is a metal source such as a metal hydroxide and a fatty acid (aliphatic monocarboxylic acid (for example, stearic acid), an aliphatic monocarboxylic acid having at least one hydroxyl group (for example, 12-hydroxystearic acid), or the like. ) synthesized. It is also possible to use the above metal source and the above aliphatic monocarboxylic acid and aliphatic dicarboxylic acid, etc. A composite metal soap synthesized from a dibasic acid.

According to different metal species, for example, lithium soap, lithium complex soap, barium soap, complex barium soap, aluminum soap, composite aluminum soap, calcium soap, complex calcium soap, sodium soap, complex sodium soap, zinc soap, composite zinc soap and many more.

The metal soap (melamine metal soap) having a guanamine bond in the molecule and the complex metal soap (complex amide metal soap) having a guanamine bond in the molecule include, for example, sodium amide sodium soap, complex sodium amide soap, guanamine钡 soap, composite amidoxime soap, amide aluminum soap, composite amide aluminum soap, guanamine calcium soap, composite guanamine calcium soap, guanidinium zinc soap, complex guanamine zinc soap and the like.

Among the above compounds, a complex lithium soap, a composite barium soap, a Na-p- citrate, and a complex amidoxime soap which are excellent in oil supply property and shear stability are particularly preferable.

The thickener of the non-urea lubricating oil is preferably 10 to 40% by weight based on the total amount of the non-urea lubricating oil. When the content is 10% by weight or less, the lubricating oil becomes soft and is easily sheared and leaks from the bearing, and when it exceeds 40% by weight, the oil content in the lubricating oil decreases, and the oil supply property may deteriorate.

The non-urea-based lubricating oil of the present invention preferably has a mixing ratio of 10 to 80% by weight based on the total amount of the lubricating oil. More preferably, it is 20 to 50% by weight. When the blending amount of the non-urea-based lubricating oil is less than 10% by weight, the oil supply property to the race portion is not good. When the amount is more than 80% by weight, the fibers of the thickener are easily broken at a high speed, so that the base oil cannot be supplied to the race portion by capillary action of the thickener.

Further, in the mixed lubricating oil of the urea-based lubricating oil and the non-urea-based lubricating oil of the present invention, a known additive for lubricating oil may be contained as needed. Examples of the additive include an organic zinc compound, an amine system, a phenol compound, and the like. Oxidation preventive agent; metal deactivator such as benzotriazole; viscosity index enhancer of polymethacrylate, polystyrene, etc.; solid lubricant of molybdenum disulfide, graphite, etc.; metal sulfonate, polyol ester A rust preventive agent; a friction reducing agent such as an organic molybdenum; an oily agent such as an ester or an alcohol; a wear preventing agent such as a phosphorus compound; These can be added individually or in combination of 2 or more types. The content of the additive is preferably 0.05% by weight or more based on the total amount of the lubricating oil, and the total amount is in the range of 0.15 to 10% by weight based on the total amount of the lubricating oil. When the total amount is more than 10% by weight, the effect of increasing the content is not expected, and the relative content of the other components is reduced, and aggregation of the additive may occur in the lubricating oil, which may cause an undesirable phenomenon such as an increase in torque.

In recent years, in general motors such as AC motors and DC motors, as motors have become smaller, the bearings tend to operate at higher speeds and higher surface pressures. Conventionally, a metal soap lubricating oil such as lithium soap is used, and sufficient durability cannot be obtained, and there is a tendency to use a urea-based lubricating oil which is more excellent in durability. The operating temperature of the motor used for the electric auxiliary equipment directly related to the automobile engine is 150 ° C or higher; the motor for the ventilating fan, the blower motor for the fuel cell, the air cleaner motor, the fan motor, the servo motor, the stepping motor, and the like The motor used for mechanical or informational machines, the motor of the starter motor, the electric steering wheel motor, the pitch control motor, the wiper motor, the electric window motor, etc., the operating temperature of the motor is mostly lower than 150 ° C. . In such a low-temperature use environment, the fluidity of the base oil of the conventional urea-based lubricating oil is not good, and in the case where higher speed is required, the base oil supplied to the raceway surface is insufficient, and lubrication is liable to occur. Bad problem.

The high-speed rolling bearing in which the high-speed bearing lubricating oil of the present invention is enclosed has an excellent oil supply property of the raceway surface even in an environment requiring high speed at the above-mentioned lower temperature, even for the above-mentioned ventilating fan. Motors for motor, fuel cell blower motors, air cleaner motors, fan motors, servo motors, stepping motors, etc., industrial motors or information machine motors, starter motors for automobiles, electric steering wheel motors, pitch control motors for direction adjustment, Motors for electric machines such as wiper motors and electric window motors can also be suitably used.

Example

The present invention will be further illustrated by the following test examples, but the present invention is not limited thereto. The data of the base oil dynamic viscosity (40 ° C) used in each of the examples and the comparative examples are shown in Tables 1 and 3. The centrifugal oil separation shown in Table 2 and Tables 4 to 7 is the value measured by the following centrifugal oil separation test.

<Centrifugal oil separation test> Using a centrifugal separator, 50 g of the lubricating oil sample was placed in a centrifugal separation tube, and centrifuged at 40 ° C and an acceleration of 23,000 G for 7 hours, and the centrifugal oil degree was determined according to the following formula.

(centrifugal oil degree %) = (1 - thickener concentration before test / thickener concentration after test) × 100

<Preparation of urea-based lubricating oil> In the half amount of the base oil shown in Table 1, it is dissolved in the proportion shown in Table 1. 4,4'-diphenylmethane diisocyanate (manufactured by Nippon Polyurethane Industry, Millionneet MT, hereinafter referred to as MDI) was added, and in the remaining half of the base oil, 2 equivalents of monoamine of MDI was dissolved. The proportions and types of each are shown in Table 1.

While stirring the solution dissolved in MDI, the solution in which the monoamine is dissolved is added, and the mixture is continuously stirred at 100 to 120 ° C for 30 minutes to carry out a reaction, whereby a diurea compound is formed in the base oil to obtain a urea-based lubricating oil. Sample.

<Preparation of non-urea lubricating oil> Non-urea lubricating oil NU1 ~ non-urea lubricating oil NU6 A non-urea lubricating oil sample was prepared by dissolving a thickener in the base oil shown in Table 1. The proportions and types of each are shown in Table 1.

Further, regarding Na bismuth citrate, the reaction of methyl-p- citrate mono-N-octadecyl decylamine with sodium hydroxide (based on base oil) produces sodium-N-octadecane-capric acid. salt.

Embodiment 1 to Embodiment 9

The urea-based lubricating oil and the non-urea-based lubricating oil shown in Table 1 were mixed at a ratio shown in Table 2 to obtain a lubricating oil sample. This lubricating oil sample was used for the above-mentioned centrifugal oil separation test and the following normal temperature high-speed lubricating oil test, and the centrifugal oil separation degree and the lubricating oil life time were measured. The measurement results are shown in Table 2.

The non-urea lubricating oil (lubricating oil NU7) of Example 9 was manufactured by NOK Klub Corporation: ISOFLEX NBU 15.

Comparative Example 1 to Comparative Example 12

The urea-based lubricating oil and the non-urea-based lubricating oil shown in Table 2 (comparatively used in Comparative Example 10) were used as lubricating oil samples. The same items as in Example 1 were measured for this lubricating oil sample. The measurement results are shown in Table 2.

<Normal temperature high-speed lubricating oil test - deep groove ball bearing (6204)> 0.14 g of the lubricating oil sample (about 3% by volume of the total volume of the bearing) was placed on the raceway surface and sealed in a deep groove ball bearing (6204), and a non-contact seal was applied to prepare each test bearing. The test bearing load axle load 670 N and the radial load weight 67 N were rotated at a rotation speed of 15000 rpm in a normal temperature environment, and the time until the occurrence of the burnt bite was measured as the lubricant life time. In this endurance test, the product of the pitch diameter dm (mm) of the bearing and the number of revolutions N (rpm) (dmN value) was 520,000.

<Normal temperature high speed ball bearing test - bevel ball bearing> Example 1, Example 2, Example 8, Example 9, Comparative Example 1. The lubricating oil sample of Comparative Example 5, Comparative Example 10 or Comparative Example 12 (3.0 g of the entire volume of the bearing) was aligned with the raceway surface to seal the bevel ball bearing (outer diameter 150 mm × inner diameter 100 mm, inside and outside) The ring SUJ2, the nitrided ball of the rotating body 13/32吋, was subjected to non-contact sealing to form each test bearing. The bearing was cooled by the outer cylinder cooling under constant pressure of 1.8 GPa for the test bearing to keep the bearing outer ring below 50 ° C and rotated at a rotational speed of 14500 rpm. The time until burnt bite occurred was measured as the life time of the lubricating oil. In this endurance test, the product of the pitch diameter dm (mm) of the bearing and the number of revolutions N (rpm) (dmN value) was 1.85 million.

As is clear from Table 2, the lubricating oil used in the present invention is preferably: (1) a lubricating oil synthesized from a urea-based lubricating oil and a non-urea-based lubricating oil, and a thickening agent of the urea-based lubricating oil is a polyisocyanate component. And a monoamine component obtained by reacting a monoamine component; the monoamine component is a monoamine component containing at least one monoamine selected from the group consisting of an aliphatic monoamine and an alicyclic monoamine with respect to the entire monoamine; (2) The non-urea thickener is a soap thickener; (3) the base oil has a dynamic viscosity of 15 to 40 mm ² /sec.

<Preparation of urea-based lubricating oil> Urea-based lubricating oil U6~urea lubricating oil U8 In half the amount of the base oil shown in Table 3, MDI was dissolved in the proportion shown in Table 3, and in the remaining half of the base oil, 2 equivalents of monoamine of MDI was dissolved. The proportions and types of each are shown in Table 3.

While stirring the solution in which the MDI was dissolved, the solution in which the monoamine was dissolved was added, and the mixture was continuously stirred at 100 to 120 ° C for 30 minutes to carry out a reaction, whereby a diurea compound was formed in the base oil to prepare a lubricating oil sample.

<Preparation of non-urea lubricating oil> Non-urea lubricating oil NU8~ non-urea lubricating oil NU10 A thickener was dissolved in the base oil shown in Table 3 to prepare a non-urea lubricating oil sample. The proportions and types of each are shown in Table 3.

Further, regarding Na bismuth citrate, the reaction of methyl-p- citrate mono-N-octadecyl decylamine with sodium hydroxide (based on base oil) produces sodium-N-octadecane-capric acid. salt.

Embodiment 10 to Embodiment 13

The urea-based lubricating oil and the non-urea-based lubricating oil shown in Table 3 were mixed at a ratio shown in Table 4 to obtain a lubricating oil sample. This lubricating oil sample was used for the above-mentioned centrifugal oil separation test and the following normal temperature high-speed lubricating oil test, and the centrifugal oil separation degree and the lubricating oil life time were measured. The measurement results are shown in Table 4.

Comparative Example 13 to Comparative Example 17

The urea-based lubricating oil or the non-urea-based lubricating oil shown in Table 4 was used as a lubricating oil sample. The same items as in Example 10 were measured for this lubricating oil sample. The measurement results are shown in Table 4.

<Normal temperature high-speed lubricating oil test - deep groove ball bearing (6204)> By the bead blasting method, alumina of particle size #100 (particle size 106-149 μm) is sprayed at a pressure of 0.2 MPa for about 20 seconds on the outer ring raceway surface of the deep groove ball bearing (6204) to be in the outer ring raceway surface. Pit processing of 2~3 μm deep is carried out, so that the test bearing is fabricated.

0.0235 g (about 0.5 vol% of the total volume of the bearing) of the lubricating oil samples of Examples 10 to 13 and Comparative Examples 13 to 17 was placed on the raceway surface, and the test bearing was sealed, and non-contact sealing was performed to prepare Individual test bearings. The test bearing load axle load 670 N and the radial load weight 67 N were rotated at a rotation speed of 10,000 rpm in a normal temperature environment, and the time until the occurrence of the burn bite was measured as the lubricant life time. In this endurance test, the product of the pitch diameter dm (mm) of the bearing and the number of revolutions N (rpm) (dmN value) was 350,000.

<Normal temperature high-speed lubricating oil test - beveled ball bearing> By bead blasting, alumina with particle size #100 (particle size 106~149 μm) is sprayed at a pressure of 0.2 MPa for about 20 seconds on an oblique ball bearing (outer diameter 150 mm × inner diameter 100 mm, inner and outer ring SUJ2, rotating body) The outer ring raceway of the 13/32 inch tantalum nitride ball is subjected to a pit process of 2 to 3 μm deep on the outer ring raceway surface, thus forming a test bearing.

3.0 g of the lubricating oil sample of Example 11, Comparative Example 13, 14 or 16 (about 10% by volume of the entire volume of the bearing) was placed on the raceway surface to seal the test bearing, and non-contact sealing was performed to prepare each test bearing. The bearing was cooled by the outer cylinder cooling under constant pressure of 1.8 GPa for the test bearing to keep the bearing outer ring below 50 ° C and rotated at a rotational speed of 14500 rpm. The time until burnt bite occurred was measured as the life time of the lubricating oil. In this endurance test, the product of the pitch diameter dm (mm) of the bearing and the number of revolutions N (rpm) (dmN value) was 1.85 million. The measurement results are shown in Table 4.

As is clear from Table 4, the lubricating oil used in the present invention is preferably (1) a lubricating oil synthesized from a urea-based lubricating oil and a non-urea-based lubricating oil, and a thickening agent of the urea-based lubricating oil is a polyisocyanate component. And a monoamine component obtained by reacting a monoamine component; the monoamine component is a monoamine component containing at least one monoamine selected from the group consisting of an aliphatic monoamine and an alicyclic monoamine with respect to the entire monoamine; (2) The non-urea thickener is a soap thickener; (3) the base oil has a dynamic viscosity of 15 to 40 mm ² /sec, and is a synthetic hydrocarbon oil, an ester oil, an alkyl diphenyl ether oil or Mix oil, etc. Further, (4) it is more preferable that at least one of the raceway surface of the inner ring selected from the high speed rolling bearing of the present invention, the raceway surface of the outer ring, and the surface of the rotor is subjected to the pit processing.

Example 14 to Example 17

The urea-based lubricating oil and the non-urea-based lubricating oil shown in Table 3 were mixed at a ratio shown in Table 5 to obtain a lubricating oil sample. This lubricating oil sample was used for the above-mentioned centrifugal oil separation test and the following normal temperature high-speed lubricating oil test, and the centrifugal oil separation degree and the lubricating oil life time were measured. The measurement results are shown in Table 5.

Comparative Example 18 to Comparative Example 24

The urea-based lubricating oil or the non-urea-based lubricating oil shown in Table 5 (comparative example 24 was used in combination) was used as a lubricating oil sample. The same items as in Example 14 were measured for this lubricating oil sample. The measurement results are shown in Table 5.

<Normal temperature high-speed lubricating oil test - deep groove ball bearing (6204)> In Example 14, Example 17, Comparative Example 18, and Comparative Example 19, a copper cyanide bath (copper cyanide, sodium cyanide, potassium hydroxide, 50 to 60 ° C) was used to support deep groove ball bearings (6204). The outer diameter of the inner ring and the inner diameter of the outer ring are subjected to metal plating treatment, and thus a test bearing is formed. The resulting coating has a thickness of about 20 μm. In Example 15 and Example 16, 7.36 g of tricresyl phosphate was diluted with 2-propanol to prepare 200 ml of a tricresyl phosphate solution, and the inner and outer rings of the deep groove ball bearing (6204) were immersed in the solution. Two hours (solution temperature: 60 ° C), whereby a metal phosphate film was formed on the surface to prepare a test bearing. In Comparative Example 20 to Comparative Example 24, a deep groove ball bearing (6204) in which a film was not formed was used as a test bearing.

0.0235 g of the lubricating oil sample shown in Table 5 (about 0.5% by volume of the total volume of the bearing) was placed on the raceway surface to seal the test bearing, and the non-performing was performed. Each test bearing is made by contacting the seal. The test bearing load axle load 670 N and the radial load weight 67 N were rotated at a rotation speed of 10,000 rpm in a normal temperature environment, and the time until the occurrence of the burn bite was measured as the lubricant life time. In this endurance test, the product of the pitch diameter dm (mm) of the bearing and the number of revolutions N (rpm) (dmN value) was 340,000.

<Normal temperature high-speed lubricating oil test - beveled ball bearing> In Comparative Example 18 and Comparative Example 19, a copper cyanide bath (cyanide cyanide, sodium cyanide, potassium hydroxide, 50 to 60 ° C) was used for the bevel ball bearing (outer diameter 150 mm × inner diameter 100 mm, inside and outside) The inner ring outer diameter and the inner diameter of the outer ring of the ring SUJ2, the niobium nitride ball of the rotating body 13/32吋 were subjected to metal plating treatment, and thus a test bearing was fabricated. The resulting coating has a thickness of about 20 μm. In Example 15, 7.36 g of tricresyl phosphate was diluted with 2-propanol to prepare 200 ml of a tricresyl phosphate solution, and the inner and outer rings of the bevel ball bearing (same as above) were immersed in the solution for 2 hours. (The solution temperature was 60 ° C), whereby a metal phosphate film was formed on the surface to prepare a test bearing. In Comparative Example 20 and Comparative Example 22, a bevel ball bearing (the same as the above) in which a film was not formed was used as a test bearing.

3.0 g of the lubricating oil sample shown in Table 5 (about 10% by volume of the entire bearing volume) was placed on the raceway surface, and the test bearings were sealed, and non-contact sealing was performed to prepare each test bearing. The bearing was cooled by the outer cylinder cooling under constant pressure of 1.8 GPa for the test bearing to keep the bearing outer ring below 50 ° C and rotated at a rotational speed of 14500 rpm. The time until burnt bite occurred was measured as the life time of the lubricating oil. In the endurance test, the shaft The product of the pitch diameter dm (mm) and the number of revolutions N (rpm) (dmN value) is 1.85 million.

As is clear from Table 5, the lubricating oil sealed in the high-speed rolling bearing is preferably: (1) a lubricating oil synthesized from a urea-based lubricating oil and a non-urea-based lubricating oil, and a thickening agent of the urea-based lubricating oil is a polyisocyanate component. And a monoamine component obtained by reacting a monoamine component; the monoamine component is a monoamine component containing at least one monoamine selected from the group consisting of an aliphatic monoamine and an alicyclic monoamine with respect to the entire monoamine; (2) The non-urea thickener is a soap thickener; (3) the base oil has a dynamic viscosity of 15 to 40 mm ² /sec. Further, (4) it is more preferable to further perform film treatment on the surface of the bearing orbital ring.

Example 18 to Example 21 and Comparative Example 25

The above-described centrifugal oil separation test and the following normal temperature high-speed lubricating oil test-deep groove ball bearing (6204) were carried out using the lubricating oil sample shown in Table 6. Centrifugal oil separation and lubricant life are listed in Table 6. In this case, the deep groove ball bearing (6204) is a crown type PA resin holder (PA66 + GF25% by weight) shown in Fig. 5, and an oil reservoir portion having a concave portion in the bag hole portion, and the edge portion including the concave portion. The contact portions with the steel balls are all subjected to the chamfering process.

Example 19 and Comparative Example 25

The above-mentioned centrifugal oil separation test and the normal temperature high-speed lubricating oil test-beveled ball bearing shown below were carried out using the lubricating oil sample shown in Table 6. Centrifugal oil separation and lubricant life are listed in Table 6. In the case of the bevel ball bearing, the phenol resin holder of the machining type shown in Fig. 3 is used, and the relief portion of the concave portion is provided at the four corners of the bag hole portion, and the concave portion is provided at both ends of the pocket hole portion in the axial direction. The oil storage portion performs a chamfering process on the edge of the concave portion.

Comparative Example 26 and Comparative Example 28

Using the lubricating oil sample shown in Table 6, the centrifugal oil separation test described above and the normal temperature high-speed lubricating oil test described below - deep groove ball bearing (6204) and normal temperature high speed lubricating oil test - bevel ball bearing were carried out. Centrifugal oil separation and lubricant life are listed in Table 6.

Comparative Example 27 and Comparative Example 29

Using the lubricating oil sample shown in Table 6, the above-described centrifugal oil separation test and the normal temperature high-speed lubricating oil test described below - deep groove ball bearing (6204) were carried out. Centrifugal oil separation and lubricant life are listed in Table 6.

<Normal temperature high-speed lubricating oil test - deep groove ball bearing (6204)> 0.0235 g (about 0.5 vol% of the total volume of the bearing) of the lubricating oil samples of Examples 18 to 21 and Comparative Examples 25 to 29 was placed on the raceway surface, and sealed in a deep groove ball bearing (6204), and non-contact sealing was performed to prepare Individual test bearings. The test bearing load axle load 670 N and the radial load weight 67 N were rotated at a rotation speed of 10,000 rpm in a normal temperature environment, and the time until the occurrence of the burn bite was measured as the lubricant life time. In this endurance test, the product of the pitch diameter dm (mm) of the bearing and the number of revolutions N (rpm) (dmN value) was 350,000.

<Normal temperature high-speed lubricating oil test - beveled ball bearing> 3.0 g of the lubricating oil sample of Example 19, Comparative Example 25, Comparative Example 26 or Comparative Example 28 (about 10% by volume of the entire bearing volume) was aligned with the raceway surface to seal the bevel ball bearing (outer diameter 150 mm × inner diameter) 100 mm, inner and outer rings SUJ2, and 13/32 turns of the nitrided ball of the rotating body) were subjected to non-contact sealing to form test bearings. The bearing was cooled by the outer cylinder cooling under constant pressure of 1.8 GPa for the test bearing to keep the bearing outer ring below 50 ° C and rotated at a rotational speed of 14500 rpm. Determination of burnt bite The time until the birth is the life of the lubricant. In this endurance test, the product of the pitch diameter dm (mm) of the bearing and the number of revolutions N (rpm) (dmN value) was 1.85 million.

As is clear from Table 6, the lubricating oil sealed in the high-speed rolling bearing is preferably: (1) a lubricating oil synthesized by a urea-based lubricating oil and a non-urea-based lubricating oil, and a thickening agent of the urea-based lubricating oil is a polyisocyanate component. And a monoamine component obtained by reacting a monoamine component; the monoamine component is a monoamine component containing at least one monoamine selected from the group consisting of an aliphatic monoamine and an alicyclic monoamine with respect to the entire monoamine; (2) The non-urea thickener is a soap thickener; (3) the base oil has a dynamic viscosity of 15 to 40 mm ² /sec. Further, (4) it is more preferable to provide the oil storage portion, the relief portion, and the like of the concave portion in the bag hole portion of the resin holder of the bearing, and perform the chamfering process.

Example 22 to Example 25

The urea-based lubricating oil and the non-urea-based lubricating oil shown in Table 3 were mixed at a ratio shown in Table 7 to obtain a lubricating oil sample. The lubricating oil sample was subjected to the above-described centrifugal oil separation test, and the centrifugal oil separation was measured. Further, the rolling bearing treated with the oil-repellent agent described below was carried out, and the obtained lubricating oil sample was sealed, and a normal-temperature high-speed lubricating oil test was carried out to measure the normal-temperature high-speed lubricating oil life time. The measurement results are shown in Table 7.

Comparative Example 30

The urea-based lubricating oil shown in Table 7 was used as a lubricating oil sample. The lubricating oil sample was subjected to the above-described centrifugal oil separation test, and the centrifugal oil separation was measured. Further, the rolling bearing treated with the oil-repellent agent described below was carried out, and the obtained lubricating oil sample was sealed, and a normal-temperature high-speed lubricating oil test was carried out to measure the normal-temperature high-speed lubricating oil life time. The measurement results are shown in Table 7.

Comparative Example 31 to Comparative Example 34

A urea-based lubricating oil or a non-urea-based lubricating oil shown in Table 7 was used as the lubricating oil sample. The lubricating oil sample was subjected to the above-described centrifugal oil separation test, and the centrifugal oil separation was measured. Further, in the rolling bearing which is not subjected to the oil-repellent treatment, the obtained lubricating oil sample is sealed, and the normal-temperature high-speed lubricating oil test is performed, and the normal-temperature high-speed lubricating oil life time is measured. The measurement results are shown in Table 7.

<oil remover treatment> A fluorine-based water-repellent oil treatment agent (LION Guard, manufactured by LION) was applied to the inner side surface of the bearing of the sealing member, and dried at room temperature for 1 hour to form a rolling bearing (deep groove ball bearing, bearing size: outer diameter 47 mm × Inner diameter 20mm × width 14mm; angled ball bearing, bearing size: outer diameter 150mm × inner diameter 100mm × width 24mm).

<Normal temperature high-speed lubricating oil test - deep groove ball bearing (6024)> 0.0235 g (about 0.5 vol% of the total volume of the bearing) of the lubricating oil samples of Examples 22 to 25 and Comparative Examples 30 to 34 were placed on the raceway surface to be sealed in a deep groove ball bearing (6024), and a non-contact seal was formed. Individual test bearings. The test bearing load axle load 670 N and the radial load weight 67 N were rotated at a rotation speed of 10,000 rpm in a normal temperature environment, and the time until the occurrence of the burn bite was measured as the lubricant life time. In this endurance test, the product of the pitch diameter dm (mm) of the bearing and the number of revolutions N (rpm) (dmN value) was 350,000.

<Normal temperature high-speed lubricating oil test - beveled ball bearing> 3.0 g of the lubricating oil sample of Example 23, Comparative Example 30, Comparative Example 31 or Comparative Example 33 (about 10% by volume of the full volume of the bearing) was aligned with the raceway surface to seal the bevel ball bearing (outer diameter 150 mm × inner diameter) 100 mm, inner and outer rings SUJ2, and 13/32 turns of the nitrided ball of the rotating body) were subjected to non-contact sealing to form test bearings. The bearing was cooled by the outer cylinder cooling under constant pressure of 1.8 GPa for the test bearing to keep the bearing outer ring below 50 ° C and rotated at a rotational speed of 14500 rpm. The time until burnt bite occurred was measured as the life time of the lubricating oil. In this endurance test, the product of the pitch diameter dm (mm) of the bearing and the number of revolutions N (rpm) (dmN value) was 1.85 million.

As is clear from Table 7, in the urea-based lubricating oil using a urea-based compound as a thickener, a non-urea-based lubricating oil containing no such urea-based compound is blended, and the urea-based compound is reacted with a polyisocyanate component and a monoamine component. In addition, the monoamine component is a monoamine component containing at least one monoamine selected from the group consisting of an aliphatic monoamine and an alicyclic monoamine with respect to the entire monoamine. The high-speed rolling bearing in which the above-mentioned lubricating oil is sealed is shown to have an excellent normal temperature and high-speed lubricating oil life time in the normal temperature high-speed lubricating oil test. More preferably, at least a portion of the inner surface of the bearing that is in contact with the lubricating oil forms a water-repellent oil-repellent coating.

In the high-speed rolling bearing in which the high-speed bearing lubricating oil is sealed, since the sealed lubricating oil is a lubricating oil synthesized by a predetermined urea-based lubricating oil and a non-urea-based lubricating oil, the bearing is durable under high-speed rotation. The life span is long. Further, by performing (1) at least one of a raceway surface selected from the inner ring, a raceway surface of the outer ring, and a surface of the rotor, (2) selected from the inner ring At least one of the outer diameter surface, the inner diameter surface of the outer ring, and the surface of the rotor forms a film, and (3) an oil reservoir and a relief portion of the recess are disposed in the pocket portion of the retainer, and the chamfering process is performed. (4) The water-repellent oil-repellent film or the like is formed on at least a part of the inner surface of the bearing which is in contact with the lubricating oil, and the bearing durability life under high-speed rotation can be further prolonged.

Therefore, it is suitable for use as a rolling bearing assembled in a main shaft of a work machine capable of high-speed sliding rotation, which includes: a lathe, a drilling machine, a boring machine, a milling machine, a grinder, a calender, an ultra-precision processing machine, a polishing machine, and the like. and Further, unlike the method of continuously supplying lubricating oil such as the oil-air lubrication method, since the lubricating oil is sealed and used, the running cost can be reduced and space can be saved.

1,11,31,51‧‧‧ oblique angle rolling bearings

2, 12, 32, 52‧ ‧ inner ring

3, 13, 33, 53‧‧‧ outer ring

4, 14, 34, 54‧‧‧ rotating body (steel ball)

5, 15, 35, 55‧‧‧ retainers

6, 16, ‧ ‧ ‧ sealing components

7‧‧‧Lubricating bag hole

15a‧‧‧ Inside the pocket

15b‧‧‧The gap

15c‧‧‧ Oil Storage Department

15d‧‧‧The edge of the recess

8, 17, 27, 37, 47‧‧‧ lubricating oil

21, 41‧‧‧ deep groove ball bearings

22. 42‧‧‧ Inner Ring

23, 43‧‧‧ outer ring

24, 44‧‧‧ rotating body

25, 45‧‧‧ keeper

25a‧‧‧ Inside the pocket

25b‧‧‧Intersection of the oil storage department

25c‧‧‧ bottom side oil storage

25d‧‧‧The edge of the recess

26, 46‧‧‧ Sealing members

38a, 38b, 38c, 38d‧‧‧ water-repellent coating

42a‧‧‧ inner ring raceway

43a‧‧‧Outer ring raceway

48a, 48b, 48c, 48d‧‧‧ water-repellent coating

Fig. 1 is a cross-sectional view showing a bevel ball bearing according to an embodiment of the high speed rolling bearing of the present invention.

Fig. 2 is a cross-sectional view showing a bevel ball bearing according to another embodiment of the high speed rolling bearing of the present invention.

Figure 3 is a perspective view of a machined retainer used in a beveled ball bearing.

Fig. 4 is a longitudinal sectional view showing a deep groove ball bearing of another embodiment of the high speed rolling bearing of the present invention.

Figure 5 is a perspective view of a crown retainer used in deep groove ball bearings.

Fig. 6 is a cross-sectional view showing an example of a position at which a water-repellent oil-repellent film of a bevel ball bearing of another embodiment of the high-speed rolling bearing according to the present invention is formed.

Fig. 7 is a cross-sectional view showing another example of the position at which the water-repellent oil-repellent film is formed.

Fig. 8 is a cross-sectional view showing another example of the position at which the water-repellent oil-repellent film is formed.

Fig. 9 is a cross-sectional view showing another example of the position at which the water-repellent oil-repellent film is formed.

Fig. 10 is a cross-sectional view showing an example of a position at which the water-repellent oil-repellent film of the deep groove ball bearing of the same embodiment is formed.

Fig. 11 is a cross-sectional view showing another example of the position at which the water-repellent oil-repellent film is formed.

Fig. 12 is a cross-sectional view showing another example of the position at which the water-repellent oil-repellent film is formed.

Fig. 13 is a cross-sectional view showing another example of the position at which the water-repellent oil-repellent film is formed.

Figure 14 is a cross-sectional view of a beveled ball bearing.

1‧‧‧inclined rolling bearings

2‧‧‧ Inner Ring

2a‧‧‧ outer ring surface of the inner ring

3‧‧‧Outer Ring

3a‧‧‧Inner diameter face of the outer ring

4‧‧‧Rotating body (steel ball)

5‧‧‧ Keeper

6‧‧‧ Sealing members

7‧‧‧Lubricating bag hole

8‧‧‧Lubricating oil

Β‧‧‧contact angle

Claims (20)

A high-speed bearing lubricating oil comprising a urea-based lubricating oil using a urea-based compound as a thickener, and a lubricating oil for a high-speed bearing comprising a non-urea-based lubricating oil not containing the urea-based compound, and characterized in that: The non-urea-based lubricating oil has a mixing ratio of 20 to 50% by weight in the entire lubricating oil for high-speed bearing, and the urea-based compound is obtained by reacting a polyisocyanate component and a monoamine component; and the monoamine component is a monoamine component containing at least one monoamine selected from the group consisting of an aliphatic monoamine and an alicyclic monoamine with respect to the entire monoamine; the thickener of the non-urea lubricating oil is a metal soap or The Na-p-cyanate, the thickener of the non-urea-based lubricating oil, is blended in an amount of 10 to 40% by weight in the entire non-urea-based lubricating oil. The lubricating oil for a high-speed bearing according to the first aspect of the invention, wherein the metal soap is a metal amide metal soap or a composite amide metal soap having a guanamine bond in the molecule. The lubricating oil for high-speed bearing according to the second aspect of the invention, wherein the amide metal soap or the composite amide metal soap is sodium, calcium, aluminum, zinc or bismuth as a metal species. The high-speed bearing lubricating oil according to the first aspect of the invention, wherein the urea-based lubricating oil and the base oil of the non-urea-based lubricating oil have a dynamic viscosity of 15 to 40 mm ² /sec. Lubrication for high speed bearings as described in item 4 of the patent application The oil, wherein the base oil of the urea-based lubricating oil is at least one selected from the group consisting of synthetic hydrocarbon oils, ester oils, and alkyl diphenyl ether oils. A high-speed rolling bearing is a high-speed rolling bearing for supporting a shaft that rotates at a high speed, and the rolling bearing has an inner ring and an outer ring, a plurality of rotating bodies interposed between the inner ring and the outer ring, a retaining member for holding the rotor, and a sealing member for covering an opening between the inner ring and the outer ring; lubricating oil is sealed around the rotating body, and the lubricating oil is used in the first item of the patent application scope. Lubricating oil. The high-speed rolling bearing according to claim 6, wherein at least one of the surface of the raceway surface selected from the inner ring, the surface of the raceway surface of the outer ring, and the surface of the rotor is subjected to pit processing. The high-speed rolling bearing according to the seventh aspect of the invention, wherein the pit processing is a beading process, and the pit formed on each surface by the processing has a depth of 0.1 to 10 μm from the surface. The high-speed rolling bearing according to claim 6, wherein at least one of an outer diameter surface selected from the inner ring, an inner diameter surface of the outer ring, and a surface of the rotor is formed to form a film. The high-speed rolling bearing according to the ninth aspect of the invention, wherein the film is a film formed by metal plating treatment or phosphoric acid film treatment. The high-speed rolling bearing according to claim 6, wherein the retainer retains the rotor by a pocket hole portion. The inner surface of the pocket portion has a recess, and at least the edge of the recess is chamfered. The high-speed rolling bearing according to claim 11, wherein the recessed portion is an oil reservoir or a relief portion. The high-speed rolling bearing according to claim 6, wherein the retainer is a resin retainer. The high-speed rolling bearing according to claim 13, wherein the resin used in the retainer is a polyamide resin, a phenol resin or a polyether ether ketone resin. The high-speed rolling bearing according to claim 6, wherein the water-repellent oil-repellent coating is formed on at least a part of the inner surface of the bearing that is in contact with the lubricating oil. The high-speed rolling bearing according to claim 15, wherein the water-repellent oil-repellent coating is formed from (1) a part of a bearing inner side surface of the sealing member, and (2) an outer ring except a track surface. The inner diameter surface and the inner side surface of the bearing of the sealing member, (3) the outer diameter surface of the inner ring other than the rail surface, and the inner side surface of the bearing of the sealing member, and (4) the retainer other than the contact surface with the rotating body At least one of the surfaces. The high-speed rolling bearing according to the fifteenth aspect of the invention, wherein the water-repellent oil-repellent film is formed using a lanthanoid compound or a fluorine-based compound. The high-speed rolling bearing according to claim 17, wherein the oxime compound is a siloxane, and the fluorine compound is a fluoroalkyl decane. The high-speed rolling bearing according to the sixth aspect of the invention, wherein the high-speed rolling bearing is a bearing for supporting a main shaft of the working machine. The high-speed rolling bearing according to the sixth aspect of the invention, wherein the high-speed rolling bearing is a bevel ball bearing or a cylindrical roller bearing.