JP5188359B2 - Rolling bearing with seal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing with a seal and a retainer for the rolling bearing with the seal capable of preventing the entry of a foreign matter into the bearing, elongating the service life of the bearing, enhancing versatility, and capable of reducing a manufacturing cost. <P>SOLUTION: In the rolling bearing 1 with the seal, a rolling element 4 held by pockets of an annular retainer 5 is interposed between an inner ring 2 and an outer ring 3, the seal 6 for sealing a bearing space is attached to the outer ring 3, a distal end of the seal 6 is brought into contact with or close to the inner ring 2, and grease Gr is sealed therein. A lubricant shifting means Js for shifting the grease Gr in the bearing space to the distal end side of the seal 6 is provided on the retainer 5. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

This invention relates to seals rolling bearings, for example, mast rollers bearing for supporting the lifting platform by rolling contact with the mast of the forklift, power tools, a technique that is applied to the construction machine or the like.

Mast roller bearings that are in rolling contact with the mast of a forklift and support a lifting platform are in practical use. That is, for example, a pair of left and right masts are provided upright at the front portion of the forklift vehicle body. The mast has a U-shaped cross section, and these masts are arranged in parallel with a U-shaped bottom face facing each other and spaced apart by a predetermined distance. An inner ring of a mast roller bearing is fitted to both ends of a shaft provided on the lifting platform, and an outer ring outer diameter surface of the mast roller bearing is configured to be capable of rolling along the guide surface of the mast. The lifting platform is driven up and down by a driving source.
A grease-filled type bearing is used for this type of mast roller bearing. Two seals are attached to the inner surface of the outer ring, and grease is sealed inside the bearing. As the grease, since a heavy load is applied, it is common to use a grease containing an extreme pressure additive. In the mast roller bearing, there is a concern that fine foreign matters such as wear powder enter the bearing.
Other bearings used for applications such as electric tools and construction machinery are concerned about the ingress of dust and water.
JP-A-9-68232 JP 2003-83345 A

When fine foreign matters such as wear powder enter the bearing, the life of the bearing is shortened due to, for example, peeling of the raceway surface. As described above, since the mast roller bearing is a grease-filled type and not a grease replenishment type, foreign matter that has once entered the bearing is not discharged to the outside. The applicant of the present application has proposed a technique that provides a dust-proof and waterproof effect by taking measures such as increasing the special seal shape and seal tension (see Patent Document 1). However, this technique requires a space for providing a protruding portion in the axial direction of the bearing, and lacks versatility as a mast roller bearing. Moreover, there is a concern that the number of parts increases and the manufacturing cost increases.
In power tool and construction machine bearings, the entry of foreign matter or the like into the bearing causes a significant decrease in bearing rotation performance and life. As countermeasures, an increase in the number of seal lips of the contact seal, an optimal shape, an increase in tightness, and installation of a slinger or the like have been performed (Patent Document 2).
The increase in the number of seal lips and the optimization of the shape of the conventional countermeasures increase the use space of the bearings, and the countermeasures due to the increase in the contact seal tightening force increase the torque. Further, in order to use a slinger, more space is required in the axial direction and the like, and the number of parts increases, leading to an increase in cost. In addition, it is conceivable to apply grease in advance to the seal groove of the inner ring. However, with this measure, grease is present in the initial stage of operation, but if the operating time becomes longer, the remaining amount of grease at that position is not sufficient. It is unknown. Accordingly, the dustproofness and waterproofness are reduced, and the rotational accuracy and life of the bearing may be reduced.

The purpose of this invention, aim to extend the life of the bearing to prevent foreign matter from entering into the bearing, it is to provide a seal with rolling bearings that can reduce the manufacturing cost to increase the versatility .

  In the rolling bearing with seal of the present invention, a rolling element held in each pocket of an annular cage is interposed between an inner ring and an outer ring, and a seal that seals a bearing space between the inner ring and the outer ring is provided with the inner ring and the outer ring. In a rolling bearing with a seal that is attached to one of the outer races, the front end of the seal is in contact with or close to the other race, and encloses a lubricant, the lubricant in the bearing space is added to the cage. A lubricant gathering means for bringing the seal toward the tip side is provided.

According to this configuration, during the bearing operation, the lubricant gathering means brings the lubricant in the bearing space closer to the front end side of the seal. Thereby, the lubricant is accumulated in the vicinity of the seal tip of the other race ring. Although the lubricant that contributes to the lubrication of the bearing ring is slightly reduced, the lubricant itself collected in the vicinity of the seal tip prevents foreign matter from entering the bearing. In the case of water, the water repellent action of the lubricant can prevent water from entering the bearing. That is, a part of the lubricant is retained in a gap between the other race ring and the seal tip, and a part of the lubricant functions as a sealant together with the seal.
In this case, a space for providing a slinger or the like in the axial direction of the bearing as in the prior art becomes unnecessary, and the versatility of the bearing can be improved. Further, the number of parts can be reduced, and the manufacturing cost can be reduced.

The lubricant gathering means is a recessed portion provided on the inner surface of the pocket of the cage and extending from the pocket opening edge on the seal proximal end side to the seal distal end side, and the lubricant in the bearing space is supplied to the cage in the cage. It moves to the seal front end side where the said dent part is not provided. When the rolling element rolls during bearing operation, the lubricant in the radial gap between the shoulder of the race ring near the base end of the seal and the circumferential surface of the cage facing the shoulder is moved to the pocket inner surface by the recess. Once captured. Thereafter, the taken-in lubricant gradually accumulates in the radial gap between the shoulder portion of the raceway near the seal tip and the circumferential surface of the cage facing the shoulder portion. In other words, the lubricant adhering to the rolling elements is scraped off by the cage peripheral surface on the side where the dent portion in the cage is not provided. In this way, the positively scraped lubricant can prevent foreign matter from entering the bearing.

The said recessed part of the said holder | retainer may be provided in multiple places located in the both sides of the center of the holder | reserver circumferential direction in the opening edge of the said pocket. In this case, even if the rolling element rolls in any direction, the lubricant can be efficiently stored in the radial gap between the shoulder portion of the race ring near the seal tip and the peripheral surface of the cage.
When the concave portion of the retainer is provided at one location spreading from the center in the circumferential direction of the retainer at the opening edge of the pocket to one side, when the post is processed by a grindstone or the like, The indented portion can be quickly processed with a grindstone. In this case, the number of processing steps can be reduced as compared with the case where the recessed portions are provided at a plurality of locations, and thus the manufacturing cost of the cage can be reduced.

The concave portion extends from the opening edge on the inner diameter side of the cage to the vicinity of the ball arrangement pitch circle, and is gradually shallower and narrower as it approaches the ball arrangement pitch circle from the inner diameter edge of the cage. good.
The lubricant gathering means is a cage cross-sectional shape portion in which the axial thickness of the seal proximal side portion in the circumferential central portion of each pocket in the cage is thinner than the axial thickness on the seal distal end side. There may be. During the operation of the bearing, the thin cage cross-sectional shape portion can bring a part of the lubricant in the bearing space to the tip side of the seal. A part of the lubricant provides a foreign matter intrusion preventing effect.

  When the protruding length in the axial direction of the outer diameter side tip of the cage at the open end of each pocket is made shorter than the protruding length in the axial direction of the inner diameter side tip of the cage, the cage can be reduced in weight. When the bearing is used at high speed, the cage stress due to centrifugal force can be reduced. When rotating at high speed, the tip of the cage is deformed so as to incline to the outer diameter side with respect to the central portion of the pocket, so that the rolling element is guided on the inner diameter side of the tip. Therefore, even if a part of the outer diameter side of the tip portion is deleted, there is no adverse effect on the bearing function.

Sheet over cage for Le rolling bearing of this, during the inner and outer rings, are interposed rolling elements retained in the respective pockets of the annular retainer, a seal for sealing the bearing space between the inner ring and the outer ring A retainer in a roller bearing with a seal that is attached to one of the inner ring and the outer ring, the tip of the seal is brought into contact with or close to the other ring, and a lubricant is sealed. Further, there is provided a lubricant gathering means for bringing the lubricant in the bearing space toward the tip end side of the seal.
By incorporating the cage provided with the lubricant gathering means into the bearing, the lubricant itself collected in the vicinity of the seal tip can prevent foreign matter from entering the bearing.
It may be a mast roller bearing in which the outer ring is in contact with the mast of the forklift to support the lifting platform. For example, even if a fine foreign matter such as wear powder enters the inside of the mast inside the mast, the foreign matter can be easily and more reliably prevented by the lubricant gathering means. The foreign matter intrusion preventing effect can be enhanced without changing the design on the forklift side such as a mast.

In the rolling bearing with seal of the present invention, a rolling element held in each pocket of an annular cage is interposed between an inner ring and an outer ring, and a seal that seals a bearing space between the inner ring and the outer ring is provided with the inner ring and the outer ring. In a rolling bearing with a seal that is attached to one of the outer races, the front end of the seal is in contact with or close to the other race, and encloses a lubricant, the lubricant in the bearing space is added to the cage. only set lubricant shifting means lapping distally of the seal, the lubricant pulling means, in the cage of provided on the inner face of the pocket recess extending from the pocket open edge of the seal base end to seal the distal end side portion There, the lubricant in the bearing space, the length of the bearing to prevent eyes is to move to the sealed distal end side of the recessed portion is not provided, intrusion of foreign matter into the bearing in the cage Achieving service life, it is possible to reduce the manufacturing cost to increase the versatility.

An embodiment of the present invention will be described with reference to FIGS. The rolling bearing according to this embodiment is a hermetically sealed deep groove ball bearing with seal, and as shown in FIGS. 2 and 3, a mast roller bearing 1 that is in rolling contact with a mast Mt of a forklift FL and supports a lifting platform Sd. As applied. However, the present invention is not limited to mast roller bearings, and is also applicable to power tools, construction machine bearings, and the like.
As shown in FIGS. 1 and 4, the bearing 1 includes a plurality of rolling elements 4 interposed between the raceway surfaces 2 a and 3 a of the inner ring 2 and the outer ring 3, and a cage 5 that holds the rolling elements 4. Provided on both side surfaces are contact-type seals 6 for sealing the bearing space. The rolling elements 4 are made of balls such as steel balls. The outer ring 3 is formed wider than the inner ring 2. As shown in FIG. 4, the inner ring 2 is fitted to both ends of the shaft Sh provided on the lifting platform Sd (FIG. 3) by an interference fit, and the outer ring outer diameter surface 3g rolls along the guide surface Mta of the mast Mt. It is configured to be accessible. The chamfered portion 3ma connecting the outer ring outer diameter surface 3g and the outer ring end surface facing the bottom surface Mtb in the mast Mt has a larger radius of curvature than the outer ring outer diameter surface 3g and the chamfered portion 3mb between the outer ring end surfaces in the axial direction. And the radius of curvature of the corner R in the mast Mt is set to be larger. This prevents the chamfered portion 3ma from undesirably interfering with the corner R in the mast Mt.

  As shown in FIG. 5, each of the seals 6 is composed of an annular cored bar 7 and a rubber-like member 8 that is integrally fixed to the cored bar 7, and a seal mounting formed on the inner peripheral surface of the outer ring 3. The seal outer periphery is fixed to the groove 9 in a fitted state. For example, the rubber-like member 8 is made of synthetic rubber, and the cored bar 7 is made of a steel plate. In the inner ring 2, a seal lip formed on the inner peripheral side end of each seal 6 is in sliding contact with the seal groove 10 of the inner ring 2.

The cage 5 will be described.

The retainer 5 is provided with a later-described lubricant gathering means for bringing the lubricant in the bearing space toward the distal end side of the seal 6.
As shown in FIGS. 6A and 7, the cage 5 is composed of, for example, two annular members 11 manufactured by stamping and forming a plate material made of an iron-based metal material, so-called an iron plate, with a press. . The material of the cage 5 is not particularly limited to the iron-based metal material, and a copper-based metal material, an aluminum-based metal material, or the like can be used.
Note that the present invention can also be applied to a two-fold resin cage and a segment cage as shown in FIGS. 6 (B) and 6 (C).
Examples of the iron-based metal material include case hardening steel (SCM), cold rolled steel (SPCC), hot rolled steel (SPHC), carbon steel (S25C to S55C), stainless steel (SUS304 to SUS316), mild steel (SS400). ) Etc. can be used.
As the copper-based metal material, a copper-zinc alloy (HBsC1, HBsBE1, BSP1-3), a copper-aluminum-iron alloy (AlBC1), etc., and as the aluminum-based metal material, an aluminum-silicon alloy (ADC12) or the like is used. it can.

  As shown in FIG. 7, each annular member 11 includes a plurality of hemispherical spherical shell-like plate portions 11a that are arranged at equal intervals in the circumferential direction and each form an inner wall surface of the pocket 5a, and adjacent spherical shell-like plates. The plate-shaped coupling plate portions 11b that connect the portions 11a are alternately formed. A rivet hole 11c is formed in the coupling plate portion 11b of the annular member 11 made of iron plate. The two annular members 11 are joined by overlapping the respective coupling plate portions 11b with each other, inserting the rivet 12 into the rivet hole 11c, and crimping both ends of the rivet 12. Other methods include welding and claw bending.

  As shown in FIG. 8, the lubricant gathering means Js is a recessed portion 13 provided on the inner surface of the pocket 5a of the cage. The recess 13 is formed so as to extend from the pocket opening edge 5ao on the seal proximal end side to the seal distal end side. In this example, as shown in FIG. 8 (B), the recessed portion 13 provided in the outer diameter side portion 11ao of the inner surface of the pocket 5a (spherical shell-shaped plate portion 11a) is formed into a cage circle at the opening edge 5ao of the pocket 5a. Two locations are provided on both sides of the center OW5a in the circumferential direction. The inner surface shape of each recess 13 is such that the cross-sectional shape along the circumferential direction of the cage (that is, the cross-sectional shape taken along the plane perpendicular to the cage central axis) is larger than the radius of curvature Ra of the concave spherical surface serving as the inner surface of the pocket 5a. The arc shape has a small radius of curvature RAb. Specifically, as shown in FIG. 8 (C), the retainer 5 has a cylindrical surface shape substantially along the surface of each virtual cylinder VA centered on the straight line LA in the radial direction. is there. The recessed portion 13 extends from the opening edge on the outer diameter side of the cage to the vicinity of the ball arrangement pitch circle PCD in the radial direction of the cage, and gradually becomes smaller from the outer diameter edge of the cage toward the ball arrangement pitch circle PCD. That is, the shape gradually becomes shallower and narrower.

As shown in FIG. 8B, the positions of the two recesses 13 in each pocket 5a are set such that, for example, the circumferential orientation angle with respect to the center OW5a in the cage circumferential direction at the opening edge of the pocket 5a is 40 °. Two symmetrical locations with ± 15 °. Also in this example, the depth of the recess 13 is such that the distance RAc from the center O11 of the concave spherical surface of the pocket inner surface to the deepest position of the recess 13 is 1.05 times or more the radius of the ball 4. Is preferable (it may be just 1.05 times).
In this embodiment, the number of the recessed portions 13 is two, but may be three or more.

In order to investigate the state of grease during operation in this bearing 1, a test was performed under the following test conditions. The state of adhesion of grease to each part of the bearing after the operation was stopped was as shown in FIG. For comparison, a comparative test was also performed under the same conditions for the bearing BR1 incorporating the conventional iron plate corrugated cage 5J in which the lubricant gathering means Js, that is, the recess 13 is not provided. The state of adhesion of grease to each part of the bearing after the operation was stopped was as shown in FIG.
<Test conditions>


Outer ring rotation: 3600rpm, operation time: 5s, load: Fa = 39.2N, temperature: room temperature The Fa is an axial load.

  According to this test, in the case of the bearing BR1 incorporating the conventional cage 5J, the grease is distributed almost uniformly throughout the bearing space, although the grease adheres slightly at appropriate circumferential intervals in the inner ring seal groove. On the other hand, in the bearing incorporating the cage 5 provided with the lubricant gathering means Js peculiar to the present application, a part of the grease is accumulated over the entire circumference near the inner ring seal groove, that is, near the seal tip of the inner ring. In the example of FIG. 9, the seal 6 is removed, but when the seal 6 is attached to the bearing 1 and the bearing is in operation, the entire circumference of the gap between the inner ring seal groove 10 and the seal tip (shown by the halftone dots in FIG. 5). Is held in a state where a part of the grease has accumulated.

According to the bearing configuration described above, the lubricant gathering means Js brings the grease in the bearing space to the tip side of the seal 6 during the bearing operation. Thereby, grease is collected near the seal tip of the inner ring 2. That is, when the rolling element 4 rolls in the direction of arrow A in FIG. 11A during the bearing operation, the shoulder 3k of the outer ring 3 in the vicinity of the seal proximal end, and the cage outer peripheral surface 5g facing the shoulder 3k, The grease Gr existing in the radial gap δ1 is once taken into the inner surface of the pocket 5a by the recess 13 (R) on the right side of FIG. Thereafter, the taken-in grease Gr is in the radial gap δ2 between the shoulder 2k of the inner ring 2 near the tip of the seal and the inner peripheral surface 5i of the cage facing the shoulder 2k, and on the left side of FIG. It gradually accumulates on the radially inner side of the recess 13 (L). Further, the grease that has entered the cage in 13 (L) adheres to the rolling 4 and adheres to the inner ring raceway surface. This grease again adheres to the rolling element 4 and is scraped off and accumulated on the radially inner side of 13 (L). In other words, the grease Gr adhering to the rolling element 4 is scraped off by the cage inner peripheral surface 5i where the recess 13 is not provided.
Conversely, when the rolling element 4 rolls in the direction of arrow B in FIG. 11 (b), the grease Gr existing in the radial gap δ1 is temporarily applied to the inner surface of the pocket 5a by the recess 13 (L) on the left side of FIG. 11 (b). It is captured. Thereafter, the taken-in grease Gr gradually accumulates in the radial gap δ2 and inward in the radial direction of the recess 13 (R) on the right side of FIG.

Although the grease contributing to the lubrication of the inner and outer rings 2 and 3 is slightly reduced, the grease itself collected in the vicinity of the seal tip prevents foreign matter from entering the bearing 1. The water repellent action of the accumulated grease can prevent water from entering. That is, the grease Gr is held in a state where a part of the grease Gr is accumulated in the gap between the inner ring seal groove 10 and the seal tip, and part of the grease functions as a sealant together with the seal 6. The grease thus scraped actively can prevent foreign matter from entering the bearing 1.
In this case, a space for providing a protrusion or the like in the axial direction of the bearing as in the prior art becomes unnecessary, and the versatility of the bearing can be improved. Further, the number of parts can be reduced, and the manufacturing cost can be reduced.
Moreover, when the said recessed part 13 is located in the both sides of the center OW5a of the holder circumferential direction in the opening edge 5ao of the pocket 5a like this example, and the rolling element 4 is provided in multiple places, Regardless of the direction of rolling, the grease Gr can be efficiently stored in the radial gap δ2 between the shoulder 2k of the inner ring 2 near the tip of the seal and the inner peripheral surface 5i of the cage.

Next, another embodiment of the present invention will be described.
In the following description, the same reference numerals are given to portions corresponding to the matters described in the preceding forms in each embodiment, and overlapping description may be omitted. When only a part of the configuration is described, the other parts of the configuration are the same as those described in the preceding section. Not only the combination of the parts specifically described in each embodiment, but also the embodiments can be partially combined as long as the combination does not hinder.

  Another example of the shape of the cage 5 in FIG. 12 is obtained by replacing the two recessed portions 13 in FIG. 8 with one location. As shown in FIG. 12 (A), the recess 13 is provided at one location extending from the center OW5a in the circumferential direction of the cage at the opening edge of the pocket 5a to one side, and the width W13 of the recess 13 The width is substantially the entire width W5a of the cage circumferential direction 5a. The width W13 of the recess 13 is preferably larger than half of the width W13 of the pocket 5a, and more preferably 2/3 or more, or 3/4 or more.

  As shown in FIG. 12B, the inner surface shape of the recessed portion 13 is a cylindrical surface shape substantially along the surface of the virtual cylinder V centered on the straight line L in the radial direction of the cage 5. The virtual cylinder V may be the surface of a grindstone that processes the recess 13. The dent 13 extends from the opening edge on the outer diameter side of the cage to the ball arrangement pitch circle PCD in the radial direction of the cage, and gradually decreases as it reaches the ball arrangement pitch circle PCD from the outer diameter edge of the cage. In other words, the shape is gradually shallower and narrower. In this embodiment, the dent 13 extends to the ball arrangement pitch circle PCD. However, even if it extends slightly to the inner diameter side of the cage from the ball arrangement pitch circle PCD, it slightly reaches the ball arrangement pitch circle PCD. It may not be.

As shown in FIG. 12A, the depth of the recessed portion 13 is such that the distance Rc from the center O11 of the concave spherical surface of the pocket inner surface to the deepest position of the recessed portion 13 is 1.05 times the radius of the ball 4 or more. It is preferable that it is the depth (it may be just 1.05 times). The radius of curvature Ra of the concave spherical surface serving as the inner surface of the pocket 5a is slightly larger than the radius of the ball 4, and is less than 1.05 of the radius of the ball 4.
According to the configuration of FIG. 12, the recess 13 holds the grease Gr in a state where a part of the grease Gr is accumulated in the gap between the inner ring seal groove 10 and the seal tip, and a part of the grease Gr functions as a sealant together with the seal 6. To do.
When post-processing this dent part 13 with a grindstone etc., the dent part 13 can be rapidly processed with one grindstone. In this case, the number of processing steps can be reduced as compared with the case where the recessed portions 13 are provided at a plurality of locations, and thus the manufacturing cost of the cage 5 can be reduced.

  Another example of the shape of the cage 5 in FIG. 13 and FIG. 14 is a holding in which the axial thickness of the seal proximal end portion in the circumferential central portion of each pocket 5a is thinner than the axial thickness of the seal distal end side. It is a vessel cross-sectional shape part. That is, the thin-walled portion 11aa is formed on the outer diameter side portion of the ball arrangement pitch circle PCD which is the ball arrangement pitch in the spherical shell-shaped plate portion 11a. This thin portion 11aa is the thickness t1 of the portion facing the inner diameter surface portion of the outer ring, which is the shoulder height on both sides of the raceway surface 3a of the outer ring 3. This plate thickness t1 is made thinner than the inner diameter side portion (that is, the seal tip side portion) of the spherical shell plate portion 11a and the plate thickness t0 of the coupling plate portion 11b. 13 and 14, the cross-sectional shape when the spherical shell plate portion 11a is not thinned is indicated by an imaginary line.

  The plate material t1 may be thinned by thinning the entire range from the portion corresponding to the ball arrangement pitch circle PCD to the outer diameter side in the cage radial direction, and the ball arrangement pitch circle PCD and the cage outer diameter. You may make it thin the range from the middle part between edges to an outer diameter edge. In these cases, the plate thickness t1 may be gradually reduced toward the outer diameter side in the cage radial direction so that the outer diameter edge becomes the minimum plate thickness, and the entire range to be thinned is substantially constant. Can be thin. Furthermore, the plate thickness may be reduced so that the shape on the outer surface side changes while maintaining the shape of the inner surface of the pocket of the spherical shell-shaped plate portion 11a. Further, the plate thickness may be reduced so that the shape on the inner surface side of the pocket changes while the outer surface shape of the spherical shell-shaped plate portion 11a is maintained. Further, as shown in FIG. 15, the thin portion 11aa having a thin plate thickness may be divided into two portions on both sides excluding the center of the arc of the outer diameter edge in the spherical shell-shaped plate portion 11a.

  13 to 15, during the bearing operation, the grease that can be deposited on the thin portion 11aa is reduced, and the frequency and amount of the grease reaching the radial gap δ1 (FIG. 11) is reduced. The grease is scraped off at the inner diameter edge of the cage, and a part of the grease accumulates over the entire circumference near the seal tip of the inner ring 2. Therefore, the grease is held in a state where a part of the grease is accumulated in the entire circumference of the gap between the inner ring seal groove 10 and the seal tip.

The retainer 5A shown in FIGS. 16 to 18 has a crown shape, and the protrusion length L1 in the axial direction of the outer diameter side distal end portion of the open side of each pocket 5Aa is determined by the length of the inner diameter side distal end portion of the cage. It is shorter than the protruding length L2 in the axial direction. In this example, as shown in FIG. 18, the distance between the tips of the pair of claws 14, 14 is gradually reduced from the cage outer diameter side toward the cage inner diameter side. The protruding length L1 of the claw portion 14a on the outer diameter side of the cage is the same as the protruding length of the claw in a general crown-shaped cage.
As shown in FIG. 19 showing a cross section along the circumferential direction of the cage of the claw 14 as the lubricant gathering means Js (cross section along the pitch circle PCD of the ball arrangement), the claw portion 14a on the cage outer diameter side from the pocket center O11. The angles θa and θb with respect to the circumferential direction of the cage facing the tip and the tip of the claw portion 14b on the cage inner diameter side are preferably set as follows. That is, the angle θb facing the tip of the claw portion 14b on the cage inner diameter side is 1.5 times or more (θb ≧ 1.5θa) of the angle θa facing the tip of the claw portion 14a on the cage outer diameter side. It is preferable to set.

The width in the cage radial direction of the claw portion 14b on the cage inner diameter side is the total width (pocket width) of the claw 14 projected on the straight line N in the cage radial direction passing through the center of the cage circumferential direction in the pocket 5Aa. Then, it is preferable to set the width Ie of the claw portion 14b on the inner diameter side of the cage projected onto the straight line N to be 2/3 or less (Ie ≦ 2 / 3It) of the full width It.
In the configuration of the crown-shaped cage 5A, grease gradually accumulates on the inner diameter surface of the cage 5A due to the difference in the protruding length of the claw portion 14. Therefore, the grease Gr is held in a state where a part of the grease Gr is accumulated around the entire circumference of the gap between the inner ring seal groove 10 and the seal tip.

  In the example of the cage 5A of FIG. 20, in the crown-shaped cage, a recess 13 extending from the pocket opening edge on the cage outer diameter side to the cage inner diameter side is provided on the inner surface of each pocket 5Aa. In this case, as in FIG. 11, the grease adhering to the rolling element 4 can be scraped off on the inner peripheral surface of the cage where the recess 13 is not provided. Although the grease contributing to the lubrication of the inner and outer rings 2 and 3 is slightly reduced, the grease itself collected in the vicinity of the seal tip prevents foreign matter from entering the bearing. That is, a part of the grease is retained in the gap between the inner ring seal groove 10 and the seal tip, and a part of the grease functions as a sealant together with the seal 6.

  In the example of the cage 5A in FIG. 21, in the crown-shaped cage, any one of the lubricant gathering means Js is provided and deleted from the inner diameter surface to the outer diameter surface on the pocket back surface side of the connecting portion 15. An example is shown. In this case, it is possible to prevent strain from concentrating on the recessed portion 13 of the pocket 5Aa and to relieve local stress concentration.

Rolled bearings with seals incorporating cages equipped with any one of the above-mentioned lubricant gathering means are applied as dustproof and waterproof ball bearings in conveyors, machine tools, robots, automobiles, motorcycles, other industrial machines, etc. May be. Even if the rolling bearing with seal is applied to any device, machine or the like, the dust-proofing and waterproofing effects can be obtained by the lubricant gathering means. Therefore, the bearing life can be extended and maintenance-free can be realized.
The seal may be a non-contact type seal. Instead of the seal, it is possible to apply a shield made of steel plate.
The seal may be attached to the inner ring, and the tip of the seal may be in contact with or close to the outer ring. In this case, the lubricant gathering means brings the lubricant in the bearing space to the tip side of the seal. As a result, a part of the lubricant is accumulated near the seal tip of the outer ring, and the lubricant can prevent foreign matter from entering the bearing.

It is a sectional view of a rolling bearing with a seal concerning one embodiment of this invention. It is a figure which shows the example which applied the rolling bearing to the bearing for mast rollers of a forklift. It is a perspective view which shows the example in which the rolling bearing carries out rolling contact in the mast. It is sectional drawing which shows the relationship between the same mast and a rolling bearing. It is an expanded sectional view of the rolling bearing. (A) is a perspective view of the cage for the rolling bearing, (B) is an exploded perspective view of a resin cage to which the cage of this embodiment can be applied, and (C) is a sectional view of the resin cage. is there. It is a perspective view of one annular member of the cage for rolling bearings. (A) The perspective view which shows the recessed part of the pocket inner surface of the holder | retainer, (B) is the elements on larger scale of the principal part of the holder | retainer, (C) is the perspective view which added the virtual cylinder to the perspective view. FIG. It is a figure which shows the grease adhesion state of the bearing incorporating the holder | retainer provided with the dent part. It is a figure which shows the grease adhesion state of the bearing incorporating the conventional cage | basket. It is a figure showing the relationship between a rolling element rotation direction and a grease adhesion position. (A) is a partial expanded perspective view of the principal part of the holder | retainer concerning other embodiment of this invention, (B) is a perspective view which shows the state which added the virtual cylinder to the perspective view. It is sectional drawing which fractured | ruptured partially the bearing incorporating the retainer concerning other embodiment of this invention. It is a principal part expansion perspective view of the holder | retainer. It is a principal part expansion perspective view of the holder | retainer which concerns on other embodiment. It is a perspective view of the bearing incorporating the retainer concerning other embodiments of this invention. It is sectional drawing which fractured | ruptured the bearing partially. It is a principal part expansion perspective view of the holder | retainer. It is explanatory drawing of the angle from the pocket center of the nail | claw tip of the holder | retainer. It is a principal part expansion perspective view of the holder | retainer which concerns on further another embodiment of this invention. It is a principal part expansion perspective view of the holder | retainer which concerns on further another embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Bearing 2 ... Inner ring 3 ... Outer ring 4 ... Rolling element 5, 5A ... Cage 5a ... Pocket 6 ... Seal 13 ... Recessed part 14 ... Claw Js ... Lubricant gathering means Mt ... Mast

Claims (7)

A rolling element held in each pocket of an annular cage is interposed between the inner ring and the outer ring, and a seal that seals the bearing space between the inner ring and the outer ring is attached to either the inner ring or the outer ring. In the case of a rolling bearing with a seal in which the tip of the seal is in contact with or close to the other race and sealed with a lubricant,
In the retainer, only setting the lubricant shifting means gather the lubricant in the bearing space of the seal distally, the lubricant pulling means, provided on the inner face of the pocket of the retainer seal base end a recessed portion extending from the pocket open edge to seal the distal end side, a lubricant in the bearing space, wherein the this is to move to the seal tip end side of the recessed portion is not provided in the retainer Rolling bearing with seal. 2. The rolling bearing with seal according to claim 1, wherein the concave portions of the cage are located on both sides of the center in the circumferential direction of the cage at the opening edge of the pocket. In Claim 1 , The said recessed part of the said holder | retainer is provided in one place spreading from the center of the holder circumferential direction in the opening edge of the said pocket to one side, and from the half of the width | variety of the pocket holder circumferential direction. A rolling bearing with a large width. In claim 2 or claim 3 , the dent extends from the opening edge on the inner diameter side of the cage to the vicinity of the ball arrangement pitch circle, and gradually becomes shallower as it approaches the ball arrangement pitch circle from the inner diameter edge of the cage. A rolling bearing with a seal that has a narrow shape. 5. The lubricant gathering means according to claim 1, wherein the lubricant gathering means calculates an axial thickness of a seal proximal end portion at a circumferential center portion of each pocket in the cage by a seal distal end side. Shi Lumpur rolling bearing comprising a retainer sectional shape portion fraction was thinner than the axial thickness of the. In any 1 item | term of Claim 1 thru | or 5 , The protrusion length to the axial direction of the cage | basket outer-diameter side front-end | tip part in the open | release side front-end | tip part of each said pocket is set to the axial direction of a cage | basket inner-diameter side front-end | tip part. Rolling bearing with seal that is shorter than the protruding length. The rolling bearing with seal according to any one of claims 1 to 6 , wherein the outer ring is in contact with a mast of a forklift to support a lifting platform.

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