TWI669222B - Texture processing method of sliding member - Google Patents

Abstract

The invention provides a texture processing method capable of forming a texture pattern with excellent shape accuracy by a novel method.

The method is to use a calendering wheel 11 formed by radiating the tip end of the scoring wheel with an arc. The scoring wheel system is formed of super-hard alloy or sintered diamond. 150 °, and has a sharp cutting edge along the peripheral edge line. While pressing the above-mentioned curved edge of the calender wheel 11 against the sliding surface of the sliding member 3 that becomes the workpiece, it is rolled on the sliding surface. Plastic deformation caused by rolling light is generated, and fine grooves 10, 10 ', 10 "are formed on the sliding surface to form rolling patterns, and a texture pattern is processed.

Description

Texture processing method of sliding member

The invention relates to a texture processing method of a sliding surface of a sliding member. Generally speaking, the so-called "texture" refers to the concept of the texture or feel of the surface of a substance. In the present invention, controlling the surface shape of a substance is called texturing, and the surface shape controlled by texturing is called a texture pattern. In addition, a process for processing a sliding surface or the like into a surface shape such as a groove, a recess (depression), or an unevenness is referred to as texture processing.

As components constituting mechanical parts, for example, a portion requiring friction reduction such as a piston, a cylinder, a valve guide, a crank neck, and a portion requiring friction resistance such as a brake or a clutch. These common requirements are to suppress the ablation and sliding that occur with the rapid increase in friction.

As one of the methods for reducing sliding and stabilizing, it is known that texturing is effective. This texturing is to form a texture pattern such as a fine groove or a recess on the sliding surface, which functions as an oil reservoir, and this method has been used. As this texturing, there are known, for example, a machining method by cutting as shown in Patent Document 1, a chemical processing method by etching as shown in Patent Document 2, or a method as described in Patent Document 3. Optical processing method by laser irradiation. In addition, in the case where friction is increased and stabilized, it is still effective to impart textures such as holes or grooves observed in commercially available brake discs.

Among the above-mentioned textured processing methods, the processing by cutting has a limit in terms of high-precision processing of fine grooves or recesses. In addition, chips are generated in the cutting process, and burrs generated in the part where the chips are cut must also be removed. Therefore, an additional grinding process step is required after the cutting process. Such a post-processing step is also required in laser processing. Step. In the etching process, since the parts are immersed in an etching solution, it is necessary to sufficiently perform cleaning in a subsequent step.

[Prior technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2006-9846

[Patent Document 2] Japanese Patent Laid-Open No. 2012-233593

[Patent Document 3] Japanese Patent No. 4111045

Furthermore, in the etching process, a masking process (pre-treatment) or a post-patterning process is required, which consumes time, and a dedicated drafting equipment or waste liquid processing equipment is required. Wait.

For this reason, laser processing has been considered to be the best method for fine texturing. However, there are problems in laser processing: when the sliding surface of the metal base material is irradiated with laser to form a minute groove or recess, metal vapor evaporated by the laser or molten metal is in the groove or recess. The vicinity of the edge is cooled, and as shown in FIG. 9 (a), it adheres again and solidifies near the periphery of the groove or recess 16 to form a so-called chip 17. The debris 17 has the disadvantage of adversely affecting the sliding properties due to adhesion to the surface of the base material.

Therefore, the generated debris must be removed by grinding. Therefore, in addition to the laser irradiation step, a new grinding removal step of the debris and a step of cleaning the metal powder generated by the grinding are newly required, which leads to an increase in the number of steps. In addition, there is a possibility that a part of the texture pattern is damaged when the debris is removed in the polishing step.

In order to suppress the generation of debris during the above-mentioned laser irradiation, Patent Document 3 discloses a method in which laser processing is performed while a lubricating oil having laser permeability is flowing on the surface of a metal base material. In this method, since the surface of the metal base material is subjected to laser irradiation while the lubricating oil is flowing, the generated metal vapor is instantly cooled and condensed in the lubricating oil. Compared with FIG. 9 (a), it can suppress the formation of debris near the groove or the recess 16 as shown in FIG. 9 (b) (see FIGS. 9 (a) and (b), which are cited in Patent Document 3). Fig. 4 (B), Fig. 5 (B)).

However, in this method, since the laser processing is performed while flowing the lubricating oil, some devices are complicated, and compared with the case where the laser irradiation is directly performed, the laser light interferes with the groove or the recess formed. The problem of reduced shape accuracy is not only the case, it is also necessary to treat the lubricating oil after use.

Therefore, in the etching process or the laser process, there are problems such as the dimensional accuracy and reproducibility of the grooves or recesses to be processed, the processing cost, and the processing time, which cannot be established as a texture processing method.

Therefore, an object of the present invention is to provide a texture processing method capable of forming a texture pattern with excellent shape accuracy on a sliding member by a novel method completely different from the previous method.

In order to solve the above problems, the following technical means have been devised in the present invention. That is, the texture processing method of the sliding member of the present invention uses a calendering wheel formed by radiating the tip end of the scoring wheel with an arc. The scoring wheel system is formed of super-hard alloy or sintered diamond and has a diameter of 1.0 to 3.0 mm. The angle of the tool tip is 90 ~ 150 °, and there is a sharp tool tip along the peripheral edge line. While pressing the above-mentioned arc-shaped tool tip of the calender wheel against the sliding surface of the sliding member that becomes the workpiece, it is placed on the sliding surface. Rolling up causes the sliding surface to undergo plastic deformation caused by calendering, and forms minute groove rolling marks on the sliding surface, thereby processing the texture pattern. Here, the "plastic deformation caused by calendering" refers to the use of the ductility and Ductility smoothes the surface so that no powder or chips are produced when plastic deformation occurs. In the present invention, a calendering wheel formed by arcuating a tip end of a cutting edge of a scoring wheel having a sharp cutting edge as a roll is used to perform calendering and groove formation together.

Furthermore, for example, the above-mentioned Patent Document 1 The "shape" can also form grooves, but the difference from "plastic deformation caused by roll calendering" is that in the case of cutting processing, one part of the object to be processed is peeled off as powder or chips, and the other is Plastic deformation. The groove formed by smoothing with roller light has a height smaller than that of the groove formed by cutting. The height of the protrusion formed on the edge of the groove is very small. Furthermore, the protrusion can be set to a fixed height It can be made into a groove of an ideal shape formed on the sliding surface. In addition, the surface hardens by calendering.

Generally speaking, a scoring wheel having a sharp blade tip formed along the peripheral edge line is used to engraving a scribe line for defining a crack advance direction when cutting a substrate of a brittle material such as a glass substrate. The process of breaking the substrate due to cracking in this way is a processing technique unique to brittle materials. Therefore, the scoring wheel has not been used so far in the cutting process of metal that is not broken due to cracking. In addition, the calendering process used to finish the metal into a smooth surface is essentially a pressing method using a calendering tool that finishes the contact surface with the workpiece into a smooth surface. A scoring wheel with a sharp tip is not used in the tool.

The present invention performs texture processing by a novel method, that is, a calender wheel formed by radiating the tip end of a cutting edge of a scribing wheel used for scoring brittle materials is used to process metals such as ductility and ductility. Thing. In addition, in addition to metal, the workpiece to be a sliding member may be brittleness such as a LTCC (Low Temperature Co-fired Ceramic) substrate before sintering (a state of a green sheet that can be deformed by pressing). material.

The groove depth of the groove formed by the rolling of the calendering wheel is preferably 1 to 6 μm, and the groove width is preferably set to a range of 0.1 to 0.4 mm. In addition, the pressing force of the calendering wheel on the sliding surface should be 0.1 to 10 N, and the rolling speed should be set to 0.1 to 2 m / s. These values are appropriately selected depending on the type or material of the sliding member to be processed. In addition, a texture of an arbitrary shape can be imparted by adjusting the pressing load and the shape of the wheel.

The calendering wheel is formed of a material that is harder than the material of the sliding member of the workpiece (such as cemented carbide or sintered diamond), and has a diameter of 1.0 to 3.0 mm and a thickness of 0.4 to 1.2mm, the angle of the tip is 90 ~ 150 °, and the tip of the tip is formed with arc. Thereby, a groove of a continuous line can be formed as a rolling mark.

In addition, a grooved calender wheel in which concave portions and convex portions are continuously formed over the entire circumference of a ridgeline portion that becomes a blade point can be used to form intermittent lines or dots on the sliding surface as rolling marks. The grooved calendering wheel has a length of the concave portion of 50 to 100 μm, a length of the convex portion of 30 to 100 μm, a blade point angle of 90 to 150 °, preferably 100 to 150 °, and a front end of the blade point is formed with an arc.

According to the present invention, the scoring wheel is rolled on the sliding surface by pressing the calender wheel formed by arcing the tip end of the scoring wheel with an arc on the sliding surface of the sliding member, thereby generating plasticity due to the calendering of the roller Deformation, forming continuous lines or intermittent lines or dots as rolling marks. Therefore, it is possible to form a micron-sized groove width or groove pitch with extremely high accuracy. In addition, a hardened effect by calendering can be obtained on the groove surface formed, and the groove surface can be a smooth surface after surface finishing, for example, and a texture pattern having excellent shape accuracy can be processed on the sliding surface.

In addition, there is no need for complicated auxiliary equipment such as the previous etching process or laser processing, but only the calender wheel is pressed on the sliding surface to move the scribe wheel and the sliding surface relatively, so it is simple The device is ready and can reduce the total cost and operating cost. In addition, as long as the material of the sliding member to be processed is a material capable of achieving plastic deformation by calendering by pressing the calender wheel, it can be processed. Therefore, it can be applied to a variety of metal materials or green sheets before sintering The state of the ceramics, etc., can greatly reduce the constraints of the material being processed, and other effects.

1‧‧‧bearing components

2‧‧‧ support rotary shaft

3‧‧‧ plain bearing (sliding member)

3a‧‧‧bearing metal

3b‧‧‧bearing metal

4‧‧‧bearing retainer

4a‧‧‧ Upper holder

4b‧‧‧ Lower holding body

5‧‧‧ connecting bolt

6‧‧‧bearing mounting surface

7‧‧‧ Lubricant supply hole

8‧‧‧Lubricant supply tank

9‧‧‧Lubricant supply path

10‧‧‧slot

10'‧‧‧ intermittent linear groove

10 "‧‧‧ intermittent dot groove

11‧‧‧ Calender Wheel

11'‧‧‧Slotted Calender Wheel

12‧‧‧ retainer

13‧‧‧rail

14‧‧‧Scratch head

15‧‧‧Jig

16‧‧‧ slot or recess

17‧‧‧ Shard

18‧‧‧ recess

19‧‧‧ convex

C‧‧‧ Arc Center

D‧‧‧ diameter

H‧‧‧ Depth

L‧‧‧Slot width

P‧‧‧Slot pitch

S1‧‧‧ length

S2‧‧‧ length

W‧‧‧ thickness

α‧‧‧ Blade angle

FIG. 1 is an exploded perspective view of a bearing member as an example of a processing object of the present invention.

FIG. 2 is a sectional view of a supporting state of a rotating shaft of the bearing member shown in FIG. 1. FIG.

Fig. 3 is a front view of a calendering wheel used in the present invention.

Fig. 4 is a front view of a scoring head portion holding a calender wheel.

5 (a) and 5 (b) are diagrams showing an example of a processing method using a groove processing jig.

Fig. 6 is an enlarged sectional view of the sliding surface after the groove processing.

Figs. 7 (a) and 7 (b) are plan views showing another embodiment of groove processing on the sliding surface.

Figure 8 (a), (b) Front view and partial enlarged view of the grooved calender roller.

9 (a) and 9 (b) are enlarged cross-sectional views of a groove after being processed by laser irradiation.

FIG. 10 is a microscope photograph showing the shape of the tip of a blade of a calender wheel according to another embodiment of the present invention.

FIG. 11 is a microscope photograph showing dents formed by the calendering wheel of FIG. 10.

Hereinafter, the texture processing method of the present invention will be described in detail based on the drawings. Here, the case where the texture processing is performed on the sliding surface of the sliding bearing which supports the rotating shaft of the crankshaft of an engine is demonstrated as an example.

FIG. 1 is a schematic exploded perspective view of a bearing member in which a plain bearing which is a processing object of the present invention is incorporated, and FIG. 2 is a sectional view of a state in which a rotary shaft is supported. In the bearing member 1 shown in the present embodiment, a sliding bearing 3 serving as a sliding member that supports the rotary shaft 2 is held by a bearing holder 4.

The bearing holder 4 is formed of an upper holder 4a and a lower holder 4b, and is coupled by a connecting bolt 5. A bearing mounting surface 6 formed of a substantially semi-cylindrical concave curved surface is provided on the inner surfaces of the upper holding body 4a and the lower holding body 4b facing each other. On these bearing mounting surfaces 6, 6 are mounted sliding bearings 3 that support the rotary shaft 2.

The plain bearing 3 is composed of a pair of upper and lower bearing metals 3a, 3b which are divided into two semi-cylindrical shapes. The bearing metal 3a, 3b is a layer that supports at least the bearing surface of the rotating shaft 2, that is, the sliding surface, and is formed of a metal material such as an aluminum alloy. In addition, a lubricating oil supply hole 7 is provided on the sliding surface. The lubricating oil supply hole 7 and the lubricant formed on the bearing mounting surface 6 of the bearing holder 4 are lubricated. The oil supply tank 8 communicates. Lubricating oil is supplied to the lubricating oil supply tank 8 from the outside through a lubricating oil supply path 9 formed in the bearing holder 4, and the lubricating oil flows from the lubricating oil supply hole 7 to the sliding surfaces of the bearing metals 3 a and 3 b.

In addition, a plurality of fine grooves 10 are formed in parallel along the entire circumference of the bearing surfaces of the bearing metals 3 a and 3 b along the circumferential direction of the rotation shaft 2. The area of the fine groove 10 is a texture pattern that functions as an oil reservoir. The texture processing method of the present invention will be described below.

In the texture processing method of the present invention, as shown in FIG. 3, a calendering wheel 11 is used in which the cutting edge of the scoring wheel having a cutting edge at the outer peripheral edge line is curved. The calendering wheel 11 is formed of a hard metal material such as a super-hard alloy or a carbon-based material such as sintered diamond. The diameter D is 1.0 to 3.0 mm, the thickness W is 0.4 to 1.2 mm, and the blade angle α is formed to 90 to 150 °. The tip of the cutting edge is formed with a radian.

As shown in FIG. 4, the calender wheel 11 is rotatably held on a holder 12. The holder 12 is assembled so as to be able to move up and down by a scoring head 14 that can be moved along a linear guide 13. Install by moving. The up and down movement of the holder 12 is performed by a hydraulic cylinder (not shown) incorporated in the scoring head 14, so that the calender wheel 11 can be pressed against the sliding surfaces of the bearing metals 3 a and 3 b with a set pressing force. on.

In the present invention, the calendering wheel 11 is pressed against the sliding surfaces of the bearing metals 3a and 3b while the calendering wheel 11 and the sliding surface are relatively moved, and the sliding surface is plastically deformed by calendering to form fine particles. The rolling traces of the grooves thereby form a texture pattern. That is, powder or chips are not generated from the processed portion (by non-cutting processing), but a texture pattern is formed using the malleable plastic deformation of the material itself.

Here, FIG. 5 is a figure which shows an example of the processing method using a jig when processing a groove. A jig 15 is prepared. The jig 15 holds the bearing metal 3a (or 3b) and swings repeatedly with the arc center C of the concave sliding surface of the bearing metal 3a as a fulcrum. As shown in FIG. 5 (a), in a state where the calendering wheel 11 is pressed on the edge of the sliding surface, the jig 15 is swung counterclockwise to the position shown in FIG. The groove 10 in the circumferential direction of the arc serves as a pressure Traces of rolling of the light wheel 11. Then, at the position shown in FIG. 5 (b), the calendering wheel 11 is moved by 1 pitch in the groove width direction and the jig 15 is swung clockwise to form a groove parallel to the groove previously processed. Hereinafter, by repeating the same steps, a texture pattern formed by a plurality of fine grooves 10 shown in FIG. 1 is formed on the sliding surfaces of the bearing metals 3a and 3b, for example.

As shown in FIG. 6, the depth H of the groove 10 formed on the sliding surfaces of the bearing metals 3 a and 3 b is preferably 1 to 6 μm, and the groove width L is preferably set to 0.1 to 0.4 mm. The groove pitch P is preferably 0.1 to 0.5 mm. In addition, the pressing force of the calendering wheel 11 on the sliding surface should be 0.1 to 10 N, and the rolling speed should be 0.5 to 2 m / s. The numerical values are appropriately selected depending on the type or material of the sliding member to be processed.

The depth H of the groove 10 can be easily adjusted to a desired value by mainly changing the shape of the cutting edge of the calender wheel 11 or the pressing force. In addition, the groove width L can be adjusted by mainly changing the size or the tip angle of the calendering wheel 11 used.

In the present embodiment, a calendering wheel 11 having a diameter D of 1.5 mm, a thickness w of 1 mm, and a tip angle α of 150 ° is used to apply a pressing force of 5 N and a rolling speed of 1 m / s to a sliding surface made of aluminum alloy. As a result, a groove having a groove depth H of 3 μm and a groove width L of 0.2 μm was processed. The groove 10 formed in this way can fully function as a reservoir.

As described above, by pressing the calender wheel 11 on the sliding surface while rolling the calender wheel 11 on the sliding surface, a fine groove 10 is formed as a rolling mark. Therefore, it is possible to easily form grooves having a micron-sized groove width L or a groove pitch P which is extremely fine. In addition, the formed groove surface can be formed into a smooth surface processed by, for example, a conventional calendering tool (a tool for performing mirror polishing by rubbing the surface of a workpiece with a pressing member such as a roller) to form a shape. Texture pattern with excellent accuracy. In this case, since the tip end of the blade edge of the calendering wheel 11 is formed with a slight arc, the effect of the calendering tool can be improved. In addition, there is no need for complicated auxiliary equipment like the previous etching process or laser processing, but only the calender wheel 11 is pressed on the sliding surface while the scribe wheel and the sliding surface are relatively moved, so it can be easily used. The device performs processing, and the processing cost can be suppressed. Again, only The material of the sliding member to be processed is a material that can be plastically deformed by pressing the calender wheel 11 and can be processed. Therefore, it can be applied to a variety of metal materials and can greatly reduce the limitation of the processed material.

Furthermore, when the material of the sliding bearing (sliding member) 3 is ceramic, it is sufficient to process the ceramic material (green sheet state) before sintering by the method described above. Accordingly, even if the ceramic is a brittle material and has high hardness, the groove 10 can be easily formed by utilizing plastic deformation caused by non-cutting.

In the above embodiment, the grooves 10 formed by the rolling of the calendering wheel 11 are set as continuous linear shapes, but they can also be processed into intermittent linear grooves 10 'as shown in FIG. 7 (a) or For example, the dot-shaped groove 10 "shown in Fig. 7 (b). In this case, as the calender roller for processing the groove 10 'or the groove 10", for example, the grooved calender roller 11' shown in FIG. 8 is used. The grooved calender wheel 11 ′ is formed with a continuous concave portion 18 and a convex portion 19 that substantially becomes a blade edge because notches are provided at a fixed pitch throughout the circumference of the blade edge. As such a grooved calendering wheel 11 ′, for example, a calendering wheel having a curved edge at the tip end of a scribe wheel “Penett” (registered trademark) manufactured by Samsung DIAMOND Co., Ltd. used for glass breaking can be used.

The grooved calender wheel 11 ′ is made of superhard alloy or sintered diamond as a material similar to the calender wheel 11 described above, with a diameter of 1.0 to 3.0 mm, a cutting edge angle α of 90 to 150 °, and a front end of the cutting edge is formed with an arc. . The length S1 of the concave portion 18 is preferably formed to be 50 to 100 μm, and the length S2 of the convex portion 19 is preferably formed to be 30 to 100 μm.

Therefore, the groove 10 'or 10 "of the intermittent line or point of the sliding surface formed as the rolling trace of the grooved calender roller 11' is separated by an interval equivalent to the length of the recess 18 of the grooved calender roller 11 ' It is formed, and the shape is formed in a size corresponding to the size of the convex portion 19. By forming the independent lines or dots intermittently in this way, the function as a reservoir can be further improved.

The sliding surface of the sliding member processed in the above manner can obtain the hardening effect by calendering, and become, for example, a smooth surface after surface finishing, and can be formed by intermittent lines or dots that play a role in oil accumulation. Achieve smooth sliding for excellent Sliding member.

FIG. 10 is a microscope photograph of the front end portion of the blade edge of a grooved calender wheel suitable for the implementation of the present invention. Compared with the grooved calender roller 11 ′ for glass breaking shown in FIG. 8, the edges of the convex portions are rounded, and the convex portions and the concave portions are smoothly connected. FIG. 11 is a microscope photograph showing dents when the scoring wheel is used to roll on a glass plate. In this case, a dent is formed which is rounder than the dent formed by the scoring wheel shown in FIG. 7.

As mentioned above, although the typical example of this invention was described, this invention is not necessarily limited to the said embodiment. For example, in the above-mentioned embodiment, in order to process the grooves 10, 10 ', and 10 ", the bearing metals 3a, 3b as the workpiece are moved relative to the calender wheels 11, 11', but the calender wheels 11, 11 'may also be moved. Move along the sliding surfaces of the bearing metals 3a, 3b. The sliding member to be processed by the present invention is not limited to the above-mentioned bearing member, but can also be applied to a reciprocating sliding member such as an engine piston or cylinder, or a valve lifter. Texture processing of the sliding surface. In addition, in the present invention, it can be appropriately modified and changed within the scope of achieving the purpose of the invention without departing from the scope of patent application.

[Industrial availability]

The invention can be applied to the texture processing of the sliding surface of a reciprocating sliding member such as a piston or a cylinder, a valve lifter, or a bearing member supporting a rotating shaft such as a crankshaft.

Claims (6)

A method for processing the texture of a sliding member, which uses a calendering wheel formed by radiating the front end of a cutting edge of a scoring wheel. The scoring wheel system is formed of super-hard alloy or sintered diamond, and the diameter is 1.0 to 3.0 mm. The angle is 90 ~ 150 °, and it has a sharp cutting edge along the peripheral edge line. While pressing the curved edge of the calender wheel against the sliding surface of the sliding member that becomes the workpiece, it is placed on the sliding surface. Rolling causes the sliding surface to undergo plastic deformation caused by calendering, and forms minute groove rolling marks on the sliding surface, thereby processing the texture pattern. For example, the texture processing method of the sliding member according to claim 1, wherein the depth of the groove formed by the rolling of the calendering wheel is 1 to 6 μm and the groove width is 0.1 to 0.4 mm. The method for processing the texture of a sliding member according to claim 1 or 2, wherein the grooves formed by the rolling of the calender wheel are formed by continuous lines. For example, the method for processing the texture of a sliding member according to claim 1, wherein the calendering wheel system is a grooved calendering wheel in which concave portions and convex portions are continuously formed over the entire ridge line portion that becomes the blade edge with the arc. The method for texture processing of a sliding member according to claim 4, wherein the grooves formed by the rolling of the grooved calender wheel are formed with intermittent lines. The texture processing method of the sliding member according to claim 4, wherein the grooves formed by the rolling of the grooved calender wheel are formed at intermittent points.