CN211039362U

CN211039362U - Combined thrust washer

Info

Publication number: CN211039362U
Application number: CN201920871528.4U
Authority: CN
Inventors: 池田真树; 滨中秀一郎
Original assignee: TPR Co Ltd
Current assignee: TPR Co Ltd
Priority date: 2018-12-21
Filing date: 2019-06-12
Publication date: 2020-07-17
Anticipated expiration: 2029-06-12
Also published as: JP2020101239A; CN110185697A; JP6856613B2; CN110185697B

Abstract

The utility model provides a combined thrust washer which can reduce the sliding load; a combined thrust washer is provided with a plurality of thrust washers, wherein at least 1 resin thrust washer (20) made of resin is arranged in the thrust washer, in a resin thrust washer (20), sliding surfaces are provided on the front and back surfaces of an annular portion (21), and further, an oil groove (25) recessed from the sliding surface (26) is provided on at least one of the front and rear surfaces, in the oil groove (25), an opening (27) recessed from the sliding surface (26) is present in the inner peripheral end of the annular portion (21), an oil stop wall (28) for separating the oil groove (25) and the outer side of the annular part (21) is arranged at the outer peripheral end part of the annular part (21), the position of the oil stop wall (28) in the thickness direction is set to be the same as that of the sliding surface (26), the presence of the oil stopper wall (28) suppresses the outflow of the lubricating oil entering the oil groove (25) to the outer peripheral side of the annular portion (21).

Description

Combined thrust washer

Technical Field

The utility model relates to a combination thrust washer that comprises a plurality of thrust washers.

Background

In some mechanical devices such as a clutch device, a gear mechanism, a compressor, and the like, thrust washers such as those shown in patent documents 1 to 4 are mounted. In the thrust washer disclosed in patent document 1, the oil groove is formed so as to extend from the through hole toward the outer peripheral side. Further, the thrust washer disclosed in patent document 2 is provided with: the thrust washer includes a1 st oil passage communicating an inner peripheral surface and an outer peripheral surface of the thrust washer, and a2 nd oil passage that is blind-communicating and has an opening at an inner peripheral surface but not an opening at an outer peripheral surface.

Further, the thrust washer disclosed in patent document 3 is provided with an arc-shaped oil supply groove or a V-shaped oil supply groove. Further, in the thrust washer disclosed in patent document 4, a structure having a1 st oil groove and a2 nd oil groove extending from an inner periphery to an outer periphery, and a communication oil groove communicating the 1 st oil groove and the 2 nd oil groove is disclosed.

Documents of the prior art

Patent document

Patent document 1: japanese patent No. 4370982

Patent document 2: japanese patent laid-open No. 2007-16931

Patent document 3: japanese patent No. 5727909

Patent document 4: japanese laid-open patent publication No. 2015-152061

SUMMERY OF THE UTILITY MODEL

Technical problem solved by the utility model

In the thrust washer, there is an opposing member, and the lubricating oil is sandwiched between the thrust washer and the opposing member. Under such circumstances, assuming that the lubrication state of the thrust washer is in a mixed lubrication region in a Stribeck diagram (Stribeck diagram), it is considered that a part is the thrust washer spaced from the opposing member by an oil film of the lubricating oil and a part is the thrust washer in direct contact with the opposing member. In such a mixed lubrication region, it is not clear how the thrust washer can be configured to reduce the sliding load. On the other hand, in recent years, there has been a further demand for thrust washers to reduce the sliding load on the sliding surface. Therefore, the demand for reduction of the high sliding load is higher than the thrust washers disclosed in the above patent documents 1 to 4.

The utility model discloses a based on the utility model of above-mentioned fact completion, aim at provides a combination thrust washer that can realize sliding load's reduction.

Means for solving the problems

In order to solve the above-described problems, according to a first aspect of the present invention, there is provided a composite thrust washer including a plurality of thrust washers each having an annular portion surrounding a through-hole, wherein at least one resin thrust washer made of a material containing a resin is provided, wherein sliding surfaces sliding against other members are provided on a front surface and a back surface of the annular portion, an oil groove recessed from the sliding surfaces and into which lubricating oil flows is provided on at least one of the front surface and the back surface, an opening portion recessed from the sliding surfaces is provided in an inner peripheral end portion of the annular portion in the oil groove, the lubricating oil enters the oil groove from a through-hole side due to the presence of the opening portion, and an oil stopper wall partitioning the oil groove and an outer side of the annular portion is provided in an outer peripheral end portion of the annular portion, and a position of the oil stopper wall in a thickness direction is set to a position equivalent to the sliding surfaces, the presence of the oil stopper suppresses the outflow of the lubricating oil entering the oil groove to the outer peripheral side of the annular portion.

In addition, according to another aspect of the present invention, in the above-described invention, preferably, the oil groove is provided with a first oil groove and a second oil groove, the first oil groove is inclined toward one side with respect to a radial direction of the annular portion, the second oil groove is inclined toward the other side different from the one side with respect to the radial direction of the annular portion, and the first oil groove and the second oil groove are connected at the opening portion.

In addition, according to another aspect of the present invention, in the above-described invention, it is preferable that at least one metal thrust washer made of metal is provided in the thrust washer.

In the present invention, it is preferable that the thrust washer has three thrust washers, and the annular portion of the thrust washer disposed at the center of the array of the three thrust washers has a smooth sliding surface on which the oil groove is not formed.

In the present invention, it is preferable that the thrust washers disposed on the one end side and the other end side of the array are resin thrust washers, and that an oil groove be provided on a surface of the resin thrust washer disposed on the one end side and the other end side of the array, the surface facing the thrust washer disposed at the center of the array.

In the present invention, it is preferable that, in the above-described invention, a smooth sliding surface in which no oil groove is formed is provided on a surface of the resin thrust washer disposed on one end side and the other end side of the array, the surface being opposite to a surface of the resin thrust washer disposed at the center of the array, the surface being opposite to the surface facing the thrust washer.

In the present invention, it is preferable that the thrust washer disposed at the center of the array of three thrust washers be a metal thrust washer made of metal.

In addition, according to another aspect of the present invention, in the above-described invention, it is preferable that the surrounding portion surrounded by the first oil groove, the second oil groove, and the opening portion is recessed in the thickness direction with respect to the sliding surface, and an oil bank portion for partitioning the surrounding portion and the first oil groove and the surrounding portion and the second oil groove is provided between them, and the position of the oil bank portion in the thickness direction is set to a position equivalent to the sliding surface.

Effect of the utility model

According to the utility model discloses, can provide one kind and can realize reducing sliding load's combination thrust washer.

Drawings

Fig. 1 is a perspective view showing a structure of a combined thrust washer according to an embodiment of the present invention.

Fig. 2 is a plan view showing the structure of a resin thrust washer constituting the combined thrust washer shown in fig. 1.

Fig. 3 is a partial plan view showing the structure of the resin thrust washer of the structural example 1.

Fig. 4 is a cross-sectional view showing a state where the oil groove shown in fig. 3 is cut in the width direction.

Fig. 5 is a partial plan view showing the structure of the resin thrust washer of the structural example 2.

Fig. 6 is a cross-sectional view showing a state where the oil groove shown in fig. 5 is cut in the width direction.

Fig. 7 is a partial plan view showing the structure of the resin thrust washer of the structural example 3.

Fig. 8 is a sectional view showing a state where the oil groove shown in fig. 7 is cut in the width direction.

Fig. 9 is a partial plan view showing the structure of the resin thrust washer according to the 4 th structural example.

Fig. 10 is a cross-sectional view showing a state where the oil groove shown in fig. 9 is cut in the width direction.

Fig. 11 is a partial plan view showing the structure of the resin thrust washer according to the structural example 5.

Fig. 12 is a cross-sectional view showing a state where the oil groove shown in fig. 11 is cut in the width direction.

Fig. 13 is a partial plan view showing the structure of the resin thrust washer according to the 6 th structural example.

Fig. 14 is a cross-sectional view showing a state where the oil groove shown in fig. 13 is cut in the width direction.

Fig. 15 is a partial plan view showing the structure of the resin thrust washer of the 8 th structural example.

Fig. 16 is a cross-sectional view showing a state where the oil groove shown in fig. 15 is cut in the width direction.

Fig. 17 is a sectional view showing a schematic structure of the load measuring apparatus.

Fig. 18 is a view showing the experimental results of experiments in which the resin thrust washers of the 1 st to 8 th structural examples were mounted on the load measuring device, respectively.

Fig. 19 is a plan view showing the structure of the metal thrust washer.

Fig. 20 is a schematic view showing the combined thrust washer of the 1 st combination mode.

Fig. 21 is a schematic view showing the combined thrust washer of the 2 nd combination mode.

Fig. 22 is a schematic view showing the combined thrust washer of the 3 rd combination mode.

Fig. 23 is a schematic view showing the combined thrust washer of the 4 th combination mode.

Fig. 24 is a schematic view showing a combined thrust washer of the 5 th combination mode.

Fig. 25 is a graph showing the results of an experiment in which the combined thrust washers of the 1 st to 5 th combination modes were mounted on a load measuring device, respectively.

Fig. 26 is a schematic diagram showing a combination thrust washer of the 6 th and 7 th combination modes.

Fig. 27 is a graph showing the results of an experiment in which the combined thrust washers of the 6 th and 7 th combination modes were mounted on a load measuring device, respectively.

Fig. 28 is a plan view showing a structure of a resin thrust washer having communicating oil grooves according to a modification of the present invention.

(symbol description)

10a combination thrust washer, 20 a resin thrust washer, 21 a ring portion, 22 a through hole, 23 an oil guide groove, 24 an oil discharge surface, 25 an oil groove, 25a first oil groove, 25b second oil groove, 26 sliding surface, 27 opening portion, 28, 110a oil stopper wall, 50 metal thrust washer, 109 an oil bank portion, 110 branched oil groove, 111 surrounding portion, 112 sliding protrusion, 113 communicating oil groove, 114a first oil groove, 114b second oil groove, 115 bottom portion, 116 dynamic pressure guide wall surface, 251 bottom portion, 252 curved wall surface, 254 dynamic pressure guide wall surface, 255 tapered wall surface, 256 convex curved surface portion, 257 wide groove portion, 258 narrow groove portion, 259, 260 concave curved surface portion, 261 inclined wall portion, 300 load measuring device, 301 oil pan, 301a inner tube portion, 301b … oil outlet, 302 … fixed shaft, 303 … rotary shaft, 304 … oil supply path, 305 … thermocouple, 306, 307 … oil seal, S1-S3 … thrust washer

Detailed Description

Hereinafter, a combined thrust washer 10 according to an embodiment of the present invention will be described with reference to the drawings.

[1 ] regarding the overall structure of the composite thrust washer 10 ]

The combined thrust washer 10 is, for example, a component incorporated in a transmission of a vehicle or a compressor of an air conditioner of a vehicle. The construction of the composite thrust washer 10 is shown in figure 1. Fig. 1 is a perspective view showing the structure of a combined thrust washer 10.

As shown in fig. 1, the combined thrust washer 10 of the present embodiment includes 3 thrust washers S1, S2, and S3. The combined thrust washer 10 including the 3 thrust washers S1, S2, and S3 is positioned between the opposing members C1 and C2, and is in a state of receiving a load in the thrust direction.

In addition, the installation environment of the combined thrust washer 10 and the opposing members C1, C2 is under the environment where lubricating oil is supplied. However, it is assumed that the lubrication state of the environment in which the combined thrust washer 10 is used is a state in a mixed lubrication region in a Stribeck diagram (Stribeck diagram), estimated from the sliding traces of the thrust washer in various experimental results and the like until the combined thrust washer 10 of the present embodiment is obtained, and the sliding load measured in various experimental results and the like. Therefore, it is presumed that an oil film is interposed in a portion between the thrust washer and the opposing member, and a portion of the thrust washer is in direct contact with the opposing member.

The thrust washers S1, S2, and S3 are configured to include at least 1 resin thrust washer 20 from (1) a resin thrust washer 20 (see fig. 2) made of a material containing resin and (2) a metal thrust washer 50 (see fig. 19) made of metal. Specifically, in the combined thrust washer 10 shown in fig. 1, the resin thrust washer 20 may be disposed on the side of the opposing member C1 and the side of the opposing member C2, and the metal thrust washer 50 may be disposed at the center; the resin thrust washer 20 may be disposed only on the side of the opposing member C1, and the metal thrust washer 50 may be disposed on the other side; the resin thrust washer 20 may be disposed only on the side of the opposing member C2, and the metal thrust washer 50 may be disposed in the remaining portion. Further, the metal thrust washer 50 may be disposed only on the side of the opposing member C1, and the remaining 2 thrust washers 20 made of resin may be disposed; the metal thrust washer 50 may be disposed only on the side of the opposing member C2, and the remaining 2 thrust washers 20 may be made of resin; the metallic thrust washer 50 may be disposed on each of the side of the opposing member C1 and the side of the opposing member C2, and the resin thrust washer 20 may be disposed at the center thereof. In addition, all of the 3 thrust washers S1, S2, and S3 may be resin thrust washers 20.

[2 ] Structure of resin thrust washer 20 ]

First, the structure of the resin thrust washer 20 constituting the composite thrust washer 10 will be described. Fig. 2 is a plan view showing the structure of a resin thrust washer 20 constituting the combined thrust washer 10 shown in fig. 1. Fig. 2 is a plan view showing the structure of a resin thrust washer 20 in structural example 1 described later.

The resin thrust washer 20 is made of any one of the following materials: (1) only the resin base material, (2) mixing the fiber material in the resin base material, (3) mixing the filler material in the resin base material, and (4) mixing the fiber material and the filler material in the resin base material. The resin base material, the fiber material, and the filler are described below.

[2.1 ] about resin base Material ]

The resin base material is any one of the following: polytetrafluoroethylene (PTFE), Polyamide (PA), imide (PAI), Polyimide (PI), Polybenzimidazole (PBI), Polyaryletherketones (PAEK), modified polyetherketone (rpl), polyphenylene sulfide (PPS), liquid crystal (lc) polymers, phenol-formaldehyde, polyethylene, polystyrene, acrylic, acrylonitrile butadiene styrene, polyacetal, polycarbonate, Polyethersulfone (PES), Polyetherimide (PEI), or a mixture of several selected from them (containing a polymer alloy or copolymer).

[2.2. relating to the fiber material ]

The average fiber length of the fiber material is, for example, a reinforcing fiber having a length of about 0.0001mm to 5mm, and the fiber material is made of inorganic fibers such as carbon fibers, glass fibers, potassium titanate fibers, and the like, and organic fibers such as aramid fibers, fluoride fibers, and the like, but is not limited thereto. Further, at least one fiber material may be selected from the above fiber materials, and a fiber material of another material may be selected and mixed therewith.

In addition, when the fiber material is glass fiber, the mixing ratio of the fiber material to the product is preferably 1 to 40% by weight. In addition, in the case where the fiber material is a carbon fiber or an aramid fiber, the weight ratio of the mixing ratio per part of the product is preferably 1 to 45% by weight. In addition, in the case that the fiber material is a fluoride fiber, the weight ratio of the mixing ratio per one part of the product is preferably 5 to 55 wt%. In addition, when the fiber material is potassium titanate fiber, the weight ratio of the mixing ratio of each part of the product is preferably 0.1 to 5% by weight.

[2.3 ] As a filler

The filling material is any one of the following materials: polytetrafluoroethylene resin (PTFE), manganese sulfide (MnS), molybdenum disulfide (MoS)₂) Graphite, calcium carbonate (CaCO)₃) Titanium oxide, Melamine Cyanate (MCA) or a mixture of several selected from them.

[2.4 ] surface treatment of resin thrust washer 20 ]

The surface treatment of the resin thrust washer 20 (the surface treatment herein also includes a surface improving treatment) may be exemplified by a surface improving treatment with epoxy silane (Shin-Etsu Silicones, Inc.), a surface improving treatment with a titanate type aluminate-based coupling agent (specifically, bis (dioctyloxypyrophosphate) isopropoxy titanate; Ajinomoto Fine-Techno Co, Inc. (manufactured by Weijisu ファインテクノ Co.): trade name 38S), a surface improving treatment with bis (dioctyloxypyrophosphate) oxyacetate titanate; trade name 138S; Ajinomoto Fine-Techno Co., manufactured by Inc. (manufactured by Weijikosu ファインテクノ Co.), an acetoacetoxy aluminum diisopropoxide compound with trade name A L-M; Ajinomoto Fine-Techno Co., Inc. (manufactured by Weijikosu ファインテクノ Co.), an surface improving treatment with trade name 55(Ajinomoto Fine-Techno Co., Inc. (manufactured by Weijikosu ファインテクノ Co.), an surface improving treatment with a surface improving treatment with ionic discharge, or a surface improving treatment with a surface improving treatment such as a low-discharge treatment, particularly, or a surface improving treatment with a corona treatment (L C, preferably, or a surface improving treatment with a corona treatment.

[3 ] concrete Structure of the resin thrust washer 20 ]

(1) Structure example 1 of resin thrust washer 20

Hereinafter, a specific structure of the resin thrust washer 20 will be described. First, the resin thrust washer 20 according to the first structural example 1 will be described. As shown in fig. 2, the resin thrust washer 20 is provided with an annular portion 21 surrounding the through-hole 22. An oil introduction groove 23 for introducing lubricating oil into an oil groove 25 is provided on the inner peripheral side (the through-hole 22 side) of the annular portion 21, and the oil introduction groove 23 is formed in a shape in which the inner peripheral wall is recessed from the through-hole 22 side toward the outer radial side. That is, a not-shown rotating shaft is disposed in the through-hole 22, and if the oil introduction groove 23 is not present, the supply of the lubricating oil along the rotating shaft is hindered, which may cause a shortage of the lubricating oil in the oil groove 25. However, the presence of the oil introduction groove 23 allows the lubricating oil to be favorably introduced into the oil groove 25.

Further, an oil-scattering surface 24 is provided on the inner peripheral side (the through-hole 22 side) of the annular portion 21. The oil-scattering surface 24 is a portion that guides the lubricating oil introduced from the oil-introducing groove 23 to the circumferential direction of the annular portion 21. The oil-scattering surface 24 is formed by processing the inner peripheral side of the annular portion 21 into, for example, a tapered shape or a curved surface shape.

Further, the annular portion 21 is provided with an oil groove 25. Fig. 3 is a partial plan view showing the structure of the resin thrust washer 20 of the structural example 1. As shown in fig. 2 and 3, the oil groove 25 is provided in the annular portion 21 so as to be recessed from the surface or the back surface facing the other members (facing members C1 and C2, other resin thrust washer 20 or metal thrust washer 50; hereinafter, collectively referred to as other members). In the following description, the front surface or the back surface of the annular portion 21 is referred to as a sliding surface 26. In the configuration shown in fig. 2, an opening 27 that opens to the through-hole 22 is provided on the inner diameter side of the oil groove 25. Therefore, the oil groove 25 is supplied with the lubricating oil from the through-hole 22 side.

On the other hand, the outer diameter side of the oil groove 25 does not communicate with the outer peripheral side of the resin thrust washer 20 (annular portion 21). That is, an oil stopper wall 28 that suppresses the outflow of the lubricating oil to the outer peripheral side is disposed on the outer diameter side of the oil groove 25. The oil stopper wall 28 and the sliding surface 26 are located on the same plane, and the oil stopper wall 28 may be provided at a level different from that of the sliding surface 26.

Here, in the configuration shown in fig. 2 and 3, the two oil grooves 25 are connected to each other on the opening 27 side, and the two oil grooves 25 are arranged in a V shape. In the following description, one of the V-shaped oil grooves 25 is referred to as a1 st oil groove 25a, and the remaining one is referred to as a2 nd oil groove 25 b. In fig. 2 and 3, the 1 st oil groove 25a is provided so as to travel clockwise from the inner diameter side to the outer diameter side thereof. On the other hand, the 2 nd oil groove 25b is provided so as to run counterclockwise from the inner diameter side to the outer diameter side thereof. In addition, when it is not necessary to distinguish between the 1 st oil groove 25a and the 2 nd oil groove 25b, they are collectively referred to as the oil grooves 25.

Here, the 1 st oil groove 25a and the 2 nd oil groove 25b may be completely connected to each other on the opening 27 side, or may be separated from each other by one wire.

In fig. 3, the intersection position P1 at which the center line L1 of the annular portion 21 intersects the center line L2 of the first oil groove 25a and the second oil groove 25b in the radial direction (width direction) is an inclination angle α 1 with respect to the center line L2 of the radial line L3 passing through the intersection position P1 and extending in the radial direction, in fig. 2, the inclination angle α 1 is preferably in the range of 30 degrees to 55 degrees, the groove width of the oil groove 25 is preferably in the range of 1.8mm to 2.8mm, the groove depth of the oil groove 25 is preferably in the range of 0.5mm to 1.0mm, and in fig. 2 and 3, the inclination angle on the first oil groove 25c side and the inclination angle on the second oil groove 25d side may be different values.

Further, the width of the oil dam 28 is preferably in the range of 0.01mm to 0.1 mm. If the width of the oil wall 28 is less than 0.01mm, it is difficult to achieve a high machining accuracy, and if the width of the oil wall 28 is greater than 0.1mm, the resin thrust washer 20 is greatly affected by the sliding load on the oil wall 28.

In addition, the cross-sectional shape of the oil groove 25 is formed as shown in fig. 4 in configuration example 1. In the configuration shown in fig. 4, a pair of substantially S-shaped curved wall surfaces 252 are provided from the bottom 251 of the oil groove 25 toward the sliding surface 26. Therefore, the lubricating oil that has entered the interior of the oil groove 25 can be satisfactorily supplied to the sliding surface 26 on any of the pair of curved wall surfaces 252.

As shown in fig. 4, a dynamic pressure guide wall surface 254 is provided so as to extend along the other curved wall surface 252 (on the X2 side in fig. 4). The dynamic pressure guide wall surface 254 is a portion for easily guiding the lubricating oil entering the oil groove 25 to the sliding surface 26. Therefore, the inclination angle θ 1 (see fig. 4) of the dynamic pressure guide wall surface 254 with respect to the sliding surface 26 is set to be much smaller than the inclination angle of the tapered wall surface 252 with respect to the sliding surface 26. By guiding the lubricating oil to the sliding surface 26 by the guide wall surface 254 for dynamic pressure, pressure (dynamic pressure) can be generated between the sliding surface 26 and another member by the lubricating oil, and the sliding load with the other member can be reduced by the pressure (dynamic pressure). The dynamic pressure guide wall surface 254 may have a portion inclined in a curved shape, in addition to a straight shape.

Here, in configuration example 1, 12 sets of the combination of V-shaped 1 st oil groove 25a and 2 nd oil groove 25b are provided. In addition, also in the 3 rd configuration example, the 4 th configuration example, the 5 th configuration example, the 6 th configuration example, and the 8 th configuration example, which will be described later, 12 sets of the combination of the 1 st oil groove 25a and the 2 nd oil groove 25b in the V-shape are provided in total, similarly to the 1 st configuration example.

Here, in fig. 3, the two-dot chain line indicates a case where the rotational direction of the resin thrust washer 20 is clockwise, and indicates the flow direction of the lubricating oil at this time. When the resin thrust washer 20 rotates clockwise, the lubricating oil flowing into the oil groove 25 from the opening 27 is supplied to the sliding surface 26 not from the 1 st oil groove 25a but mainly from the 2 nd oil groove 25b by the centrifugal force. In fig. 3, the dotted line indicates a case where the rotational direction of the resin thrust washer 20 is counterclockwise, and indicates the flow direction of the lubricating oil at this time. When the resin thrust washer 20 rotates counterclockwise, the lubricating oil is supplied not from the 2 nd oil groove 25b but mainly from the 1 st oil groove 25a to the sliding surface 26 due to the centrifugal force acting on the lubricating oil.

(2) Example 2 of the structure of the resin thrust washer 20

Next, the resin thrust washer 20 of the configuration example 2 will be explained. Fig. 5 is a plan view showing the structure of the resin thrust washer 20 of the structural example 2. Fig. 6 is a cross-sectional view showing a state in which the oil groove 25 shown in fig. 5 is cut in the width direction. The oil groove 25 of configuration example 2 is different in cross-sectional shape along the width direction from the oil groove 25 of configuration example 1, but the resin thrust washer 20 of configuration example 2 is similar in structure to the resin thrust washer 20 of configuration example 1 except for the cross-sectional shape of the oil groove 25.

In the oil groove 25 of the 2 nd configuration example shown in fig. 5 and 6, a tapered wall surface 255 is provided from the bottom 251 of the oil groove 25 toward one side (the X1 side in fig. 6). That is, the tapered wall surface 255 is continuous with one side of the bottom portion 251. The tapered wall surface 255 is a portion that is inclined linearly with a predetermined inclination angle with respect to the sliding surface 26. The tapered wall surface 255 may have a portion inclined in a curved line, in addition to a straight line. On the other hand, a curved wall surface 252 is provided from the bottom 251 toward the other side (X2 side in fig. 6) in the same manner as the oil groove 25 shown in fig. 4. That is, the curved wall surface 252 is continuous with the other side of the bottom portion 251. The width-directional length (dimension c2) of the tapered wall surface 255 is set to be substantially 4 times the dimension a 2.

Here, in the configuration in which the two oil grooves 25 are arranged in a V shape, as shown in fig. 5, the tapered wall surface 255 is provided so as to be located on the inner diameter side of the curved wall surface 252 in the width direction of the oil groove 25. Thus, when the resin thrust washer 20 rotates, the lubricating oil is supplied to the sliding surface 26 at a portion not surrounded by the two oil grooves 25. However, the tapered wall surface 255 may be provided so as to be located on the outer diameter side of the curved wall surface 252 in the width direction of the oil groove 25.

In addition, in configuration example 2, the combination of the 1 st oil groove 25a and the 2 nd oil groove 25b in the V shape is provided in 6 sets at equal intervals in the circumferential direction of the annular portion 21. However, the combination of the 1 st oil groove 25a and the 2 nd oil groove 25b in the V shape may be provided in several groups.

(3) Example 3 of the structure of the resin thrust washer 20

Next, the resin thrust washer 20 of the configuration example 3 will be explained. Fig. 7 is a plan view showing the structure of the resin thrust washer 20 of the 3 rd structural example. Fig. 8 is a cross-sectional view showing a state in which the oil groove 25 shown in fig. 7 is cut in the width direction. Further, although the oil groove 25 of the 3 rd configuration example has a planar shape different from that of the oil groove 25 of the 1 st configuration example, the cross-sectional shape of the oil groove 25 in the resin thrust washer 20 of the 3 rd configuration example is the same as that of the resin thrust washer 20 of the 1 st configuration example. That is, in the oil groove 25 of the 3 rd configuration example, as in the oil groove 25 of the 1 st configuration example, a bottom portion 251 and a pair of substantially S-shaped curved wall surfaces 252 directed from the bottom portion 251 toward the sliding surface 26 side are provided. In the oil groove 25 of configuration example 3, the curved wall surface 252 on the other side (X2 side in fig. 8) is provided so as to extend with a dynamic pressure guide wall surface 254 inclined linearly.

As shown in fig. 7, in oil groove 25, a branch oil groove 110 is provided in addition to 1 st oil groove 25a and 2 nd oil groove 25b connected in a V-shape. Branch oil groove 110 is an oil groove connected to branch from 1 st oil groove 25a and 2 nd oil groove 25b, respectively. In the structure shown in fig. 7, the branch oil grooves 110 are connected to the 1 st oil groove 25a and the 2 nd oil groove 25b in a lower case "y" or in a reverse manner. The outer diameter side of branch oil groove 110 does not communicate with the outer peripheral side of resin thrust washer 20 (annular portion 21), and oil stopper wall 110a is disposed on the outer diameter side of branch oil groove 110, similarly to oil groove 25.

In the configuration shown in fig. 7, the branch oil groove 110 connected to the 1 st oil groove 25a and the branch oil groove 110 connected to the 2 nd oil groove 25b are provided to have the same width. However, the 2 branch oil grooves 110 may be respectively provided to have different widths. For example, branch oil groove 110 connected to 1 st oil groove 25a may be formed to have a width wider than or the opposite of the width of branch oil groove 110 connected to 2 nd oil groove 25 b. Further, an oil stopper wall 110a that suppresses the outflow of the lubricating oil from branch oil groove 110 to the outer circumferential side is provided on the outer circumferential side of branch oil groove 110. The width of the oil stopper wall 110a can be set to be the same as the width of the oil stopper wall 28.

(4) Example of the No. 4 construction of the resin thrust washer 20

Next, the resin thrust washer 20 of the 4 th structural example will be described. Fig. 9 is a plan view showing the structure of the resin thrust washer 20 of the 4 th structural example. Fig. 10 is a cross-sectional view showing a state in which the oil groove 25 shown in fig. 9 is cut in the width direction. Further, the oil groove 25 of the 4 th structural example is different in planar shape from the oil groove 25 of the 1 st structural example, but the resin thrust washer 20 of the 4 th structural example is the same as the resin thrust washer 20 of the 1 st structural example except for the vicinity of the sectional shape of the oil groove 25.

Specifically, as shown in fig. 10, a tapered wall surface 255 is provided from the bottom 251 of the oil groove 25 toward one side (X1 side in fig. 10). That is, the tapered wall surface 255 is continuous with one side of the bottom portion 251. On the other hand, the inclined wall portion 109a of the oil bank portion 109 is provided from the bottom portion 251 toward the other side (X2 side in fig. 10). That is, the inclined wall 109a is continuous with the other side of the bottom 251. Here, in the configuration shown in fig. 10, the width-directional length (dimension c14) of the tapered wall surface 255 is set to be a dimension substantially 2 times as large as the dimension a 4.

The height H41 of the oil bank 109 from the bottom 251 is equal to the height H42 of the sliding surface 26 from the bottom 251. The oil bank 109 is provided with a pair of

inclined walls

109a and 109b with a ceiling 109c interposed therebetween. As described above, the inclined wall portion 109a is an inclined wall located on the other side (X2 side) of the oil groove 25 and is inclined linearly. The inclined wall 109b is an inclined wall located on the opposite side of the inclined wall 109a with the apex 109c interposed therebetween, and is inclined linearly like the inclined wall 109 a. As shown in fig. 10, the inclined wall 109a is disposed on one side (X1 side) of the ceiling portion 109c, and the inclined wall 109b is disposed on the other side (X2 side) of the ceiling portion 109 c. The

inclined walls

109a and 109b are not limited to a straight line, and may be curved.

The bottom portion 251 side of the inclined wall portion 109a and the surrounding portion 111 (described later) side of the inclined wall portion 109b are linearly provided. However, the top 109c side of the

inclined wall portions

109a, 109b is provided in a curved shape.

Further, the top portion 109c may be provided flat, but the width of the top portion 109c is very narrow compared to the width of the bottom portion 251, the curved wall surface 252, and the like. Since the width of the apex 109C is extremely narrow, the apex 109C is brought into contact with other members (the other resin thrust washer 20, the metal thrust washer 50, the counter members C1, C2, and the like) in a line contact state. To describe this point in detail, as shown in fig. 9 and 10, a surrounding portion 111 surrounded by the two oil grooves 25 (two oil stopping walls 28) is provided between the 1 st oil groove 25a and the 2 nd oil groove 25 b. The height of the surrounding portion 111 is set lower than the height of the top portion 109c as shown in fig. 10. Therefore, the following structure is obtained: when the resin thrust washer 20 rotates, the surrounding portion 111 may not contact other members even if the apex 109c contacts other members.

When the resin thrust washer 20 rotates, the surrounding portion 111 is covered with the lubricating oil that has passed over the apex 109 c. By covering the surrounding portion 111 with the lubricating oil, the surrounding portion 111 can be kept out of contact with other components.

In this way, when the resin thrust washer 20 rotates, the surrounding portion 111 having a low height may not contact other members, and the top portion 109c may contact other members, so that the sliding load can be reduced as compared with a structure in which the surrounding portion 111 does not exist. In addition, the height of the surrounding portion 111 may be the same as the bottom portion 251, or may be slightly higher or lower than the bottom portion 251. Further, when the resin thrust washer 20 rotates, the top portion 109c may contact other members, but naturally, the top portion 109c may not contact other members due to the presence of the lubricating oil.

(5) Structure example 5 of resin thrust washer 20

Next, the resin thrust washer 20 of the 5 th structural example will be described. Fig. 11 is a plan view showing the structure of the resin thrust washer 20 of the 5 th structural example. Fig. 12 is a cross-sectional view showing a state in which the oil groove 25 shown in fig. 11 is cut in the width direction. Further, although the oil groove 25 of the 5 th structural example has a planar shape different from the oil groove 25 of the 1 st structural example, the oil groove 25 of the resin thrust washer 20 of the 5 th structural example has a bottom portion 251 in the same manner as in the 1 st structural example. The following description deals with differences between the resin thrust washer 20 of the 5 th structural example and the resin thrust washers 20 of the 1 st to 4 th structural examples.

As shown in fig. 12, the resin thrust washer 20 of the 5 th structural example is provided with a convex curved surface portion 256 similar to the substantially S-shaped curved wall surface 252. The convex curved surface portion 256 is a convex curved surface connecting the bottom portion 251 and the sliding surface 26, and has a cross-sectional shape having no inflection point unlike the curved wall surface 252 having a substantially S-shape. In the structure shown in fig. 12, the convex curved surface portion 256 is provided in the same shape as a rounded chamfer, for example. However, the convex curved surface portion 256 may have a part of a straight line or a part of a concave curved surface, in addition to a convex curved surface portion. Instead of the convex curved surface portion 256, a straight inclined surface similar to the tapered wall surface 255 may be provided.

In the structure shown in fig. 11, the oil groove 25 has a wide groove portion 257 and a narrow groove portion 258. These wide groove portions 257 and narrow groove portions 258 are provided continuously on the same straight line. As shown in fig. 11, the wide groove portions 257 are provided to be larger than the narrow groove portions 258. The narrow groove portion 258 is connected to the opening 27, and the oil stopper wall 28 is present on the back side of the wide groove portion 257. In the structure shown in fig. 11, the width of the wide groove portions 257 is set to a dimension of approximately 2 to 2.5 times the width of the narrow groove portions 258.

(6) Example 6 of the structure of the resin thrust washer 20

Next, the resin thrust washer 20 of the 6 th structural example will be described. Fig. 13 is a plan view showing the structure of the resin thrust washer 20 of the 6 th structural example. Fig. 14 is a cross-sectional view showing a state in which the oil groove 25 shown in fig. 13 is cut in the width direction. In the resin thrust washer 20 according to configuration example 6, the oil grooves 25 are different from the resin thrust washers 20 according to configuration examples 1 to 5 in that the two oil grooves 25 are not arranged in a V shape, and the individual oil grooves 25 are arranged to extend in a direction inclined with respect to the radial direction. However, in the resin thrust washer 20 of the 6 th structural example, the two oil grooves 25 may be arranged in a V-shape.

Oil groove 25 of configuration example 6 includes bottom portion 251 and dynamic pressure guide wall surface 254, as in oil groove 25 of configuration example 2. Further, oil groove 25 of configuration example 6 includes convex curved surface portion 256, similarly to oil groove 25 of configuration example 5. However, the resin thrust washer 20 of the 6 th structural example is provided with the sliding protrusions 112 similar to the oil bank 109 from the bottom portion 251 toward the other side (X2 side in fig. 13 and 14). The sliding protrusion 112 is a portion that is in contact with the opposing member C1 or C2 and smoothes the roughness of the surface of the opposing member C1 or C2. Therefore, the sliding projection 112 is provided to be flush with the sliding surface 26 or to slightly protrude from the sliding surface 26. Instead of the convex curved surface portion 256, a straight inclined surface similar to the tapered wall surface 255 may be provided. The sliding projection 112 may be provided slightly lower than the sliding surface 26.

As shown in fig. 13 and 14, an inclined wall portion 112a of the sliding protrusion 112 is provided from the bottom portion 251 toward the other side (X2 side in fig. 13 and 14). That is, the inclined wall portion 112a is continuous with the other side of the bottom portion 251. The top surface 112b of the sliding projection 112 is continuous with the inclined wall 112 a. The top surface portion 112b is provided flat as with the top portion 109 c. Further, a concave curved surface portion 113b described later is continuous with the top surface portion 112 b.

Further, in the resin thrust washer 20 of the 6 th structural example, the communication oil groove 113 is provided from the sliding protrusion 112 toward the other side (the X2 side in fig. 13 and 14). The communicating oil groove 113 has no oil stopper wall 28 on the outer diameter side of the annular portion 21, and the lubricating oil freely flows from the through-hole 22 to the outer diameter side. In the structure shown in fig. 13 and 14, the communication oil groove 113 is provided recessed from the sliding surface 26 together with the oil groove 25. In the configuration shown in fig. 13 and 14, the communication oil groove 113 is provided linearly in parallel with the oil groove 25. However, the communication oil groove 113 may not be parallel to the oil groove 25, and may be provided, for example, along the radial direction of the resin thrust washer 20. The communication oil groove 113 may be curved instead of being linear.

The bottom 113a of the communicating oil groove 113 is provided at the same height as the bottom 251, and the bottom 113a may have a height slightly different from the height of the bottom 251. Further, as shown in fig. 14, the bottom portion 113a is provided continuously with the pair of concave

curved surface portions

113b, 113 c. A concave curved surface portion 113b is provided on one side (X1 side in fig. 14) of the bottom portion 113a, and a concave curved surface portion 113c is provided on the other side (X2 side in fig. 14) of the bottom portion 113 a. These concave

curved surfaces

113b and 113c are concave curved surfaces connecting the bottom portion 113a and the sliding surface 26, and have a cross-sectional shape having no inflection point, unlike the curved wall surface 252 having a substantially S-shape. In the structure shown in fig. 14, the concave

curved surface portions

113b and 113c are provided in the shape of, for example, rounded chamfers. However, the concave

curved portions

113b and 113c may have, for example, a linear portion in addition to a curved portion. The curved portion may or may not be present in the bottom portion 113 a.

When such a communicating oil groove 113 is provided, the flow rate of the lubricating oil passing through the communicating oil groove 113 toward the outer diameter side can be increased. Therefore, the resin thrust washer 20 can have good heat dissipation properties.

(7) 7 th structural example of resin thrust washer 20

Next, a resin thrust washer 20 according to configuration example 7 will be described. The resin thrust washer 20 of the 7 th structural example is provided with the same oil groove 25 as the resin thrust washer 20 of the 2 nd structural example, and the bottom 251, the substantially S-shaped curved wall surface 252, and the tapered wall surface 255 are provided in the same oil groove 25. Therefore, the illustration thereof is omitted. However, in the 7 th configuration example, the combination of the 1 st oil groove 25a and the 2 nd oil groove 25b in the V shape is provided with 8 sets at equal intervals in the circumferential direction of the annular portion 21. This point is different from the 2 nd configuration example in which 6 sets of the 1 st oil groove 25a and the 2 nd oil groove 25b are provided in total in the annular portion 21.

(8) Example 8 of the structure of the resin thrust washer 20

Next, a resin thrust washer 20 according to a configuration example 8 will be described. Fig. 15 is a plan view showing the structure of a resin thrust washer 20 according to the 8 th structural example. Fig. 16 is a cross-sectional view showing a state in which the oil groove 25 shown in fig. 15 is cut in the width direction.

In resin thrust washer 20 according to structure example 8, length of 1 st oil groove 25a and 2 nd oil groove 25b is set short. Therefore, there is a sufficient distance between the back side (the side away from opening 27) of 1 st oil groove 25a and 2 nd oil groove 25b and the outer peripheral portion of resin thrust washer 20.

Further, in the resin thrust washer 20 of the 8 th structural example, an oil reservoir 114 is provided in addition to the oil reservoir 25. The oil reservoir 114 is a concave portion having no opening 27 on the inner diameter side thereof. In the structure shown in fig. 15, two oil reservoirs 114 are provided. The 2 oil reservoirs 114 are connected to each other at the inner diameter side in a V-shape. However, the reservoir 114 may not be arranged in a V shape. In the following description, one of the V-shaped oil reservoirs 114 is referred to as a1 st oil reservoir 114a, and the other remaining oil reservoir is referred to as a2 nd oil reservoir 114 b. The 1 st reservoir 114a is provided so as to travel clockwise from the inner diameter side to the outer diameter side thereof. And the 2 nd reservoir 114b is provided so as to run counterclockwise from the inner diameter side thereof to the outer diameter side thereof.

In addition, in the 8 th structural example, the cross-sectional shapes of the oil groove 25 and the oil reservoir 114 are the same. Specifically, a curved wall surface 252 having a substantially S-shape is provided from the bottom 251 of the oil groove 25 toward one side (the X1 side in fig. 16). That is, the substantially S-shaped curved wall surface 252 is continuous with one side of the bottom portion 251. In the curved wall surface 252, a concave curved surface portion 259 that is a concave curved surface is provided continuously with the bottom portion 251, and a convex curved surface portion 256 that is a convex curved surface is provided continuously with respect to the concave curved surface portion 259. Further, a dynamic pressure guide wall surface 254 continuous with the convex curved surface portion 256 and the sliding surface 26 is provided therebetween. Instead of the convex curved surface portion 256, a straight inclined surface similar to the tapered wall surface 255 may be provided.

On the other hand, the concave curved surface portion 260 is provided continuously from the bottom portion 251 toward the other side (X2 side in fig. 16) with the bottom portion 251. The inclined wall portion 261 inclined linearly is provided continuously with the concave curved surface portion 260. Further, a sliding surface 26 is provided from the inclined wall portion 261 toward the other side (X2 side in fig. 16). The inclined wall 261 may be curved. The inclined wall 261 may have a curved surface.

Similarly to the oil grooves 25, the sliding surface 26 is provided from the bottom 115 (see fig. 15) of the oil reservoir 114 toward one side in the width direction via a concave curved surface portion (not shown) similar to the concave curved surface portion 259, a convex curved surface portion (not shown) similar to the convex curved surface portion 256, and a dynamic pressure guide wall surface 116 (see fig. 15) similar to the dynamic pressure guide wall surface 254. The sliding surface 26 is provided from the bottom portion 115 toward the other side in the width direction via a concave curved surface portion (not shown) similar to the concave curved surface portion 260 and an inclined wall portion (not shown) similar to the inclined wall portion 261. Instead of the convex curved surface portion similar to the convex curved surface portion 256, a straight inclined surface similar to the

inclined wall portions

109a and 109b may be provided.

[2.6 ] evaluation (experimental result) concerning the shape of the oil groove 25 of the resin thrust washer 20 according to the 1 st to 8 th structural examples ]

Next, an experiment was performed on the sliding load of the resin thrust washer 20 according to the above-described 1 st to 8 th structural examples. That is, in the case where any resin thrust washer 20 is used, an experiment was conducted as to whether or not the sliding load is reduced. The results of this experiment are as follows.

In configuration example 1 (see fig. 4), dimension a1 corresponding to the width of bottom portion 251 is 0.5mm, dimension b1 corresponding to the width of oil groove 25 is 1.0mm, dimension c1 corresponding to the width of dynamic pressure guide wall surface 254 is 0.5mm, the angle θ 1 of inclination with respect to sliding surface 26 of dynamic pressure guide wall surface 254 is 3 degrees, and height H1 from bottom portion 251 to sliding surface 26 is 0.25 mm. In addition, in configuration example 2 (see fig. 6), a dimension a2 corresponding to the width of the bottom portion 251 is 0.5mm, a dimension c2 corresponding to the width of the tapered wall surface 255 is 2.25mm, a dimension d2 corresponding to the width of the curved wall surface 252 on the other side (on the X2 side in fig. 6) is 0.2mm, and a height H2 from the bottom portion 251 to the sliding surface 26 is 0.25 mm. In configuration example 3 (see fig. 8), the dimension a3 corresponding to the width of the bottom portion 251 is 1.0mm, the dimension b3 corresponding to the width of the oil groove 25 is 1.5mm, the dimension c3 corresponding to the width of the dynamic pressure guide wall surface 254 is 0.5mm, the angle θ 3 of the dynamic pressure guide wall surface 254 with respect to the sliding surface 26 is 3 degrees, and the height H3 from the bottom portion 251 to the sliding surface 26 is 0.25 mm.

In the 4 th configuration example (see fig. 10), the dimension a4 corresponding to the width of the bottom portion 251 is 0.5mm, the dimension c4 corresponding to the width of the tapered wall surface 255 is 1.0mm, the dimension f4 corresponding to the width of the top portion 109c is 0.05mm, the height H41 from the bottom portion 251 to the top portion 109c is 0.25mm, the height H42 from the bottom portion 251 to the sliding surface 26 is 0.25mm, the inclination angles θ 41 and θ 42 of the

inclined wall portions

109a and 109b with respect to the bottom portion 251 are 45 degrees, and the curved surface between the

inclined wall portions

109a and 109b and the top portion 109c is R0.3. In the 5 th configuration example (see fig. 12), the dimension a5 corresponding to the width of the bottom portion 251 is 0.5mm, the dimension b5 corresponding to the width of the oil groove 25 is 2.0mm, the height H5 from the bottom portion 251 to the sliding surface 26 is 0.25mm, and the curved surface of the convex curved surface portion 256 is R2.

In the 6 th configuration example (see fig. 14), the dimension a6 corresponding to the width of the bottom portion 251 is 0.5mm, the dimension b6 corresponding to the width of the oil groove 25 is 1.8mm, the dimension c6 corresponding to the width of the dynamic pressure guide wall surface 254 is 2.0mm, the dimension e6 corresponding to the width of the top surface portion 112b is 0.2mm, the dimension f6 corresponding to the width of the communicating oil groove 113 is 0.7mm, the dimension g6 in the width direction (X direction) of the inclined wall portion 112a is 0.2mm, the height H6 from the bottom portion 251 and the bottom portion 113a to the sliding surface 26 and the top surface portion 112b is 0.2mm, the inclination angle θ 6 of the dynamic pressure guide wall surface 254 with respect to the sliding surface 26 is 3 degrees, the curved surface of the convex curved surface portion is R0.7, and the curved surfaces of the concave

curved surfaces

113b and 113c are R0.2.

In the 8 th configuration example (see fig. 16), the dimension a8 corresponding to the width of the bottom portion 251 is 0.8mm, the dimension b8 corresponding to the width of the oil groove 25 is 1.3mm, the dimension c8 corresponding to the width of the dynamic pressure guide wall surface 254 is 1.0mm, the inclination angle θ 8 of the dynamic pressure guide wall surface 254 with respect to the sliding surface 26 is 6 degrees, and the height H8 from the bottom portion 251 to the sliding surface 26 is 0.25 mm. The curved surface of the concave curved surface portion 259 is R0.3, the curved surface of the convex curved surface portion 256 is R0.3, and the curved surface of the concave curved surface portion 260 is R0.3.

In all of the resin thrust washers 20 according to the 1 st to 8 th structural examples of the relevant dimensions, the outer diameter thereof was 73mm, the inner diameter thereof was 59mm, and the thickness thereof was 1.5 mm. The resin thrust washer 20 is made of a polyether ketone resin (PEK) material under the trade name of 150FC30 (manufactured by VICTREX (ビクトレックス)). The resin thrust washer 20 is not subjected to surface treatment. The counter members C1 and C2 were S45C (JIS standard) which was a high tensile steel, and had a diameter of 73mm and a surface roughness of Rz 6. mu.m. Further, ATF was used as the type of the lubricating oil, and the oil temperature in the experiment was 120 ℃. In addition, during the experiment, the load was 360N, the rotation speed was 5200rpm, and the oil flow rate was 1000 cc/min.

The resin thrust washer 20 was subjected to measurement of a sliding load using a load measuring device 300 shown in fig. 17. The load measuring device 300 includes a cylindrical oil pan 301, and the lubricating oil is supplied to an inner cylindrical portion 301a of the oil pan 301. Oil pan 301 is also provided with oil outlet 301 b. The oil discharge port 301b is an opening portion for discharging the lubricating oil present in the inner tube portion 301a to the outside.

The load measuring device 300 includes a fixed shaft 302 and a rotating shaft 303. The fixed shaft 302 is a shaft that does not rotate relative to the oil pan 301. However, a load in the pressing direction is applied to the fixed shaft 302 by a load supply means not shown in the drawings. Further, on the fixed shaft 302, the opposing member C2 is attached in a non-rotational state with respect to the fixed shaft 302.

The rotary shaft 303 is a shaft that rotates relative to the oil pan 301. Therefore, a rotational force is applied to the rotary shaft 303 by a rotational force supply means, which is not shown. Further, on the rotary shaft 303, a counter member C1 is attached in a non-rotatable state with respect to the rotary shaft 303. Further, the shaft-shaped portion C1a for attaching the resin thrust washer 20 is provided on one of the opposing members C1. And the other opposing member C2 is provided in a disk shape. Therefore, the dimension in the axial direction of one of the opposing members C1 is set to be larger than that of the other opposing member C2 by the amount corresponding to the shaft-like portion C1 a.

As shown in fig. 17, center holes (reference numerals are omitted) are provided to penetrate the fixed shaft 302, the opposite member C1, and the other opposite member C2. These center holes are axially continuous to form an oil supply passage 304 through which lubricating oil flows. Further, an oil supply port 302a is formed in the fixed shaft 302, and the oil supply port 302a is an opening portion for supplying lubricating oil to the oil supply passage 304. Further, on the opposing member C2, a thermocouple 305 is mounted. The thermocouple 305 is a portion for measuring the temperature of the sliding surface of the opposing member C2. Further, an oil seal 306 is provided in the oil pan 301 at an opening portion (reference numeral omitted) for inserting the fixed shaft 302 into the inner cylindrical portion 301 a. Further, an oil seal 307 is also provided in the oil pan 301 at an opening portion for inserting the rotary shaft 303 into the inner cylindrical portion 301 a.

Fig. 18 shows the experimental results of the experiment in which the resin thrust washers 20 of the 1 st to 8 th structural examples were mounted on the load measuring device 300. In fig. 18, the average torque (sliding load; the same applies hereinafter) in the resin thrust washer 20 of the 1 st structural example is 0.35N · m, the average torque in the resin thrust washer 20 of the 2 nd structural example is 0.3N · m, the average torque in the resin thrust washer 20 of the 3 rd structural example is 0.33N · m, the average torque in the resin thrust washer 20 of the 4 th structural example is 0.27N · m, the average torque in the resin thrust washer 20 of the 5 th structural example is 0.27N · m, the average torque in the resin thrust washer 20 of the 6 th structural example is 0.37N · m, the average torque in the resin thrust washer 20 of the 7 th structural example is 0.34N · m, and the average torque in the resin thrust washer 20 of the 8 th structural example is 0.37N · m.

According to the experimental results, the results obtained were: the resin thrust washer 20 having the smallest sliding load is the resin thrust washer 20 of the 4 th structural example shown in fig. 9 and 10.

[3 ] concrete Structure of Metal thrust washer 50 ]

Next, a description will be given regarding the structure of the metal thrust washer 50. Fig. 19 is a plan view showing the structure of the metal thrust washer 50. As shown in fig. 19, in the metal thrust washer 50, an annular portion 201 is also provided so as to surround the through-hole 202, similarly to the resin thrust washer 20. However, the annular portion 201 does not have a portion such as the oil groove 25 existing in the resin thrust washer 20. That is, the sliding surface 203 such as the front surface or the back surface of the annular portion 201 of the metal thrust washer 50 is smoothly provided without grooves such as oil grooves.

On the inner circumferential side of the metal thrust washer 50, at least one of the oil introduction groove and the oil release surface may be present, or none of them may be present, as in the case of the resin thrust washer 20.

The metal thrust washer 50 is thinner than the resin thrust washer 20. This makes it possible to reduce the overall thickness of the combined thrust washer 10 made up of 3 thrust washers each including the metal thrust washer 50. However, the thickness of the metal thrust washer 50 may be the same as that of the resin thrust washer 20.

The material of the metallic thrust washer 50 is, for example, a material having a good thermal conductivity such as copper or iron, an aluminum alloy may be considered as a material depending on a resin (combined) to be used for sliding (for example, polyamide imide (PAI) or polyether imide (PEI)), or a surface treatment such as D L C or Mo coating may be applied to the metallic thrust washer 50.

[4 ] combination of thrust washers S1 ]

Next, a combined thrust washer 10 including at least 1 of the resin thrust washers 20 according to the above-described 1 st to 8 th structural examples will be described.

[4.1. combination principle ]

First, the basic principle of the combined thrust washer 10 will be explained. Specifically, if the number of the thrust washers S1 constituting the combined thrust washer 10 is 2 or more, any number of them may be used. However, at least 1 resin thrust washer 20 needs to be present among 2 or more thrust washers S1.

For example, when the combined thrust washer 10 is configured by 2 or more thrust washers S1 to S2, it is conceivable to dispose the thrust washer S1 on the side of one opposing member C1 and the thrust washer S2 on the side of the other opposing member C2. At this time, the one opposing member C1 and the other opposing member C2 are in a state of relative rotation. In this case, the thrust washer S1 is in a state of being relatively rotated or relatively not rotated with respect to the one opposing member C1. The thrust washer S2 is in a state of being relatively rotated or relatively not rotated with respect to the other opposing member C2.

In this state, at least one of the thrust washer S1 and the thrust washer S2 is the resin thrust washer 20, and the oil groove 25 is formed in at least one of the front surface and the back surface of the resin thrust washer 20. Then, lubricating oil is supplied between the members (any of the opposing members C1, C2, thrust washers S1, S2) opposing the sliding surface 26 where the oil groove 25 exists.

The manner of supplying the lubricating oil to the opposing portion differs depending on the specific shape of the oil groove 25 and the like. However, as a reference example of the lubricating oil supply, there is a case shown in fig. 3. In fig. 3, the lubricating oil is introduced into the oil groove 25 from the opening 27, and the lubricating oil is supplied from the oil groove 25 to a facing portion including the sliding surface 26.

On the other hand, as a comparative object, a case where only one resin thrust washer 20 is disposed between the opposing members C1 and C2 is considered. In this case, the sliding load can be reduced significantly as compared with the case where the resin thrust washer 20 is not disposed between the opposing members C1 and C2. Here, in the case where only 1 resin thrust washer 20 is used, the rotation difference between the opposing member C1 and the opposing member C2 is defined as N, and the rotation difference between the surface of the resin thrust washer 20 and the opposing member C1 is defined as N11. Further, a rotation difference between the back surface of the resin thrust washer 20 and the opposing member C2 is defined as N21. In the following description, N11 and N21 are also denoted as allocation items. In this case, the rotation difference N is expressed as the following equation:

N-N11 + N21 … (formula 1)

On the other hand, a case is considered in which the thrust washer S1 of the 2 thrust washers S1, S2 is the resin thrust washer 20, and the resin thrust washer 20 faces the opposing member C1. At this time, the rotation difference between the opposing member C1 and the opposing member C2 is defined as N, and the rotation difference between the surface of the resin thrust washer 20 and the opposing member C1 is defined as N12. Further, a rotation difference between the back surface of the resin thrust washer 20 and the surface of the thrust washer S2 was defined as N22, and a rotation difference between the back surface of the thrust washer S2 and the opposing member C2 was defined as N32. In this case, the rotation difference N is expressed by the following equation. In addition, in the following description, N12, N22, and N32 are also denoted as allocation items.

N-N12 + N22+ N32 … (formula 2)

As is clear from the comparison of the above-described (expression 1) and (expression 2), the rotation difference per allocation item can be reduced by allocating the rotation difference N between the opposing member C1 and the opposing member C2 to 3 allocation items so as to "N12 + N22+ N32", as compared with the case where the rotation difference N between the opposing member C1 and the opposing member C2 is allocated to 2 allocation items so as to "N11 + N21". Therefore, (equation 2) can reduce the sliding load on a per-allocation-item basis more than (equation 1).

When the opposing members C1 and C2 are not subjected to a predetermined surface treatment, the surface roughness is larger than that of the thrust washers S1 and S2 (including the resin thrust washer 20). In this case, the value obtained by adding the sliding loads based on the distribution items N12, N22, and N32 of (expression 2) (the total of the sliding loads) can be reduced from the value obtained by adding the sliding loads based on the distribution items N11 and N21 of (expression 1) (the total of the sliding loads). That is, the relative rotation difference of the facing surface with respect to the surface having the large surface roughness can be reduced, and the entire sliding load can be reduced.

In addition, when 3 thrust washers S1 to S3 are used, the distribution term becomes 4. In this case, the relative rotation difference of the opposing surface with respect to the surface having a large surface roughness can be reduced, and the entire sliding load can be further reduced. In addition, in the case where P thrust washers of 4 or more are used, the number of distribution items is P + 1. In this case, the relative rotation difference of the opposing surface with respect to the surface having a large surface roughness can be further reduced, and the entire sliding load can be further reduced.

[4.2 ] outline of combination of sliding surfaces 26 with oil grooves 25 when the combined thrust washer 10 is composed of 3 thrust washers S1 to S3 ]

When the combined thrust washer 10 is composed of 3 thrust washers S1 to S3, all of the thrust washers 20 may be made of resin, 2 of the thrust washers 20 may be used, or only 1 of the thrust washers 20 may be made of resin. In the resin thrust washer 20, the oil grooves 25 may be formed on both the front surface and the back surface, or the oil grooves 25 may be formed only on either the front surface or the back surface of the resin thrust washer 20.

In addition, any one of the thrust washers 1 to 8 can be used as the resin thrust washer 20 constituting the combined thrust washer 10.

Here, when 3 resin thrust washers 20 are used, there are 6 surfaces and back surfaces in total. Therefore, the at least one oil groove 25 is present in the at least one resin thrust washer 20 and is present in a total of 63 combinations on at least one of the face and the back including the resin thrust washer 20. Thus, the composite thrust washer 10 may be any of the 63 combinations described above.

[4.3 ] A case where the composite thrust washer 10 is constituted by 3 resin thrust washers 20 ]

Hereinafter, in the case where the combined thrust washer 10 is composed of 3 resin thrust washers 20, experiments are performed on a preferable combination of the sliding surfaces 26 having the oil grooves 25. The experimental results will be described below.

That is, with respect to the combined thrust washer 10 composed of 3 resin thrust washers 20, the most preferable candidates for the combined thrust washer 10 were selected from the above-mentioned 63 combinations in total, and experiments were performed on these candidates. The results are described below. In this experiment, all the oil grooves 25 were uniform in the same shape (the same configuration example). Since it is not possible to clearly determine how the oil grooves 25 are preferably arranged on the 3 resin thrust washers 20 and their front/rear surfaces unless experiments are performed with all the same shapes. Specifically, when the oil groove 25 is provided in the resin thrust washer 20, the oil groove 25 of the resin thrust washer 20 in configuration example 1 is provided. Fig. 20 to 24 show the arrangement of the oil grooves 25.

In fig. 20 to 24, the surface on which the oil groove 25 is provided is marked with a symbol "Y" and hatched. And the surface on which the oil groove 25 is not provided is marked with the symbol "N" without hatching. In fig. 20 to 24, the side of the counter member C1 will be referred to as the upper side (Z1 side), and the side of the counter member C2 will be referred to as the lower side (Z2 side).

The resin thrust washer 20 of the 1 st structural example used in this experiment was the same in size as the thrust washer subjected to the experiment shown in fig. 18. The experimental conditions in this experiment were the same as those in the experiment shown in fig. 18. The load measuring device 300 shown in fig. 17 is also used. However, in fig. 17, 1 resin thrust washer 20 was attached to the load measuring device 300, and 3 resin thrust washers 20 were attached to the load measuring device 300 in the experiment.

(1) Arrangement of oil grooves 25 in a combined thrust washer 10 in a first combined mode

Fig. 20 shows a schematic view of the composite thrust washer 10 in a first assembled mode. In the combined thrust washer 10 of the 1 st combination mode, the oil grooves 25 are disposed on all of the front and back surfaces of the 3 resin thrust washers 20.

(2) Arrangement of oil grooves 25 in a combined thrust washer 10 of a second combined mode

Fig. 21 shows a schematic view of the composite thrust washer 10 in a second composite mode. In the combined thrust washer 10 of the second combined mode, the oil grooves 25 are not provided on the front and back surfaces of the resin thrust washer 20 in the center of the 3 resin thrust washers 20, and the oil grooves 25 are provided on the front and back surfaces of the other 2 resin thrust washers 20.

(3) Arrangement of oil grooves 25 in combined thrust washer 10 of third combined mode

Fig. 22 shows a schematic view of the composite thrust washer 10 in a third composite mode. In the combined thrust washer 10 of the third combined mode, the oil grooves 25 are not provided on the front surface and the back surface of the resin thrust washer 20 at the center among the 3 resin thrust washers 20. The oil groove 25 is not disposed on the front surface (surface on the Z1 side) of the resin thrust washer 20 on the upper side (Z1 side; facing member C1 side), and the oil groove 25 is disposed on the back surface (surface on the Z2 side). The oil groove 25 is disposed on the front surface (surface on the Z1 side) of the resin thrust washer 20 on the lower side (on the Z2 side; on the opposing member C2 side), and the oil groove 25 is not disposed on the back surface (surface on the Z2 side).

(4) Arrangement of oil grooves 25 in combined thrust washer 10 of fourth combination mode

Fig. 23 shows a schematic view of the combined thrust washer 10 in a fourth combination mode. In the combined thrust washer 10 of the fourth combination mode, the oil grooves 25 are disposed on the front surface and the back surface of the resin thrust washer 20 at the center among the 3 resin thrust washers 20. The oil groove 25 is disposed on the front surface (Z1 side surface) of the resin thrust washer 20 on the upper side (Z1 side; facing member C1 side), and the oil groove 25 is not disposed on the rear surface (Z2 side surface). The oil groove 25 is not disposed on the front surface (surface on the Z1 side) of the resin thrust washer 20 on the lower side (on the Z2 side; on the opposing member C2 side), and the oil groove 25 is disposed on the back surface (surface on the Z2 side).

(5) Arrangement of oil grooves 25 in combined thrust washer 10 in fifth combined mode

Fig. 24 shows a schematic view of the combined thrust washer 10 in a fifth combined mode. In the combined thrust washer 10 of the fifth combined mode, the oil grooves 25 are disposed on the front surface and the back surface of the resin thrust washer 20 at the center among the 3 resin thrust washers 20. The oil groove 25 is not provided on the front surface (surface on the Z1 side) and the back surface (surface on the Z2 side) of the resin thrust washer 20 on the upper side (on the Z1 side; on the opposing member C1 side). The oil groove 25 is not provided on the front surface (surface on the Z1 side) and the back surface (surface on the Z2 side) of the resin thrust washer 20 on the lower side (on the Z2 side; on the opposing member C2 side).

[4.4 ] evaluation concerning the combined thrust washer 10 of the 1 st to 5 th combination modes (experimental results)

Fig. 25 shows the results of an experiment in which the combined thrust washers 10 of the 1 st to 5 th combination modes were mounted on the load measuring device 300. In fig. 25, the average torque (sliding load; the same applies hereinafter) is 0.34N · m in the combined thrust washer 10 of the 1 st split mode, 0.32N · m in the combined thrust washer 10 of the 2 nd split mode, 0.28N · m in the combined thrust washer 10 of the 3 rd split mode, 0.26N · m in the combined thrust washer 10 of the 4 th split mode, and 0.35N · m in the combined thrust washer 10 of the 5 th split mode.

From the experimental results, the following results were obtained: when 3 resin thrust washers 20 are used, the combined thrust washer 10 having the smallest sliding load is the combined thrust washer 10 of the 4 th combined mode shown in fig. 23.

The above experiment was performed on the resin thrust washer 20 provided with the oil grooves 25 (oil grooves 25 of the first structural example 1) having the same shape. Therefore, it can be considered that: in the 1 st to 5 th split dies, the same results can be obtained by using the oil grooves 25 according to the 2 nd to 8 th structural examples and the oil grooves 25 having the same shape for each of the resin thrust washers 20.

[4.5 ] A case where the metal thrust washer 50 is used as the center thrust washer S2 in the case of the combined thrust washer 10 including 3 thrust washers S1 to S3 ]

Next, an experiment was performed on the sliding load in which the resin thrust washer 20 at the center was replaced with the metal thrust washer 50, as compared to the case where 3 resin thrust washers 20 were combined. The results of this experiment are described below.

(1) Arrangement of oil grooves 25 in combined thrust washer 10 in 6 th combination mode

Fig. 26 shows a schematic view of the composite thrust washer 10 in the 6 th combination mode. In the combined thrust washer 10 of the 6 th combination mode, the metal thrust washer 50 is disposed at the center of the row. The oil groove 25 is not disposed on the surface (surface on the Z1 side) of the resin thrust washer 20 on the upper side (Z1 side; facing member C1 side), and the oil groove 25 is disposed on the back surface (surface on the Z2 side). The oil groove 25 is disposed on the front surface (surface on the Z1 side) of the resin thrust washer 20 on the lower side (on the Z2 side; on the opposing member C2 side), and the oil groove 25 is not disposed on the back surface (surface on the Z2 side). In this case, the oil grooves 25 having the shape of the 1 st configuration example shown in fig. 3 and 4 are provided in the 2 resin thrust washers 20.

(2) Arrangement of oil grooves 25 in combined thrust washer 10 in 7 th combination mode

In the combined thrust washer 10 in the 7 th combination mode, only the shape of the oil groove 25 is changed with respect to the combined thrust washer 10 in the 6 th combination mode. Specifically, in the combined thrust washer 10 of the 7 th combination mode, the oil groove 25 having the shape of the 4 th structural example shown in fig. 9 and 10 is provided in the resin thrust washer 20.

In the combined thrust washer 10 of the 7 th split mode, the resin thrust washer 20 and the metal thrust washer 50 are arranged in the same manner as the combined thrust washer 10 of the 6 th split mode. In addition, the surfaces of the 2 resin thrust washers 20 on which the oil grooves 25 are formed are also the same as the resin thrust washer 20 shown in fig. 26. Therefore, a separate illustration of the 7 th combination mode is omitted.

[4.6 ] evaluation concerning the combined thrust washer 10 of the 6 th and 7 th combination modes (experimental results)

Fig. 27 shows the results of experiments in which the combined thrust washers 10 of the 6 th and 7 th combination modes were mounted on the load measuring device 300. Fig. 27 shows the combined thrust washer 10 of the 3 rd split mode and the 4 th split mode as a comparison target of the combined thrust washer 10 of the 6 th split mode and the 7 th split mode.

In fig. 27, the average torque (sliding load; the same applies hereinafter) is 0.27N · m in the combined thrust washer 10 of the 6 th split mode, and is 0.23N · m in the combined thrust washer 10 of the 7 th split mode.

From the experimental results, the results are: when 3 thrust washers S1 to S3 are used, the combined thrust washer 10 having the smallest sliding load is the combined thrust washer 10 of the 7 th mode.

5. Effect of action

In the combined thrust washer 10 configured as described above, the thrust washer is provided with at least 1 resin thrust washer 20 made of resin, and in the resin thrust washer 20, sliding surfaces 26 that slide relative to other members (opposing members C1, C2) are provided on the front and rear surfaces of the annular portion 21, and oil grooves 25 that are recessed from the sliding surfaces 26 and into which lubricating oil enters are provided on at least one of the front and rear surfaces. In the oil groove 25, an opening 27 recessed from the sliding surface 26 is present at an inner peripheral end portion of the annular portion 21, and the presence of the opening 27 allows the lubricating oil to enter from the through-hole 22 side, and an oil stopper wall 28 is provided at an outer peripheral end portion of the annular portion 21 to separate the oil groove 25 from the outside of the annular portion 21. The oil stopper wall 28 is provided at a position approximately equal to the sliding surface 26 in the thickness direction, and the presence of the oil stopper wall 28 suppresses the outflow of the lubricating oil entering the oil groove 25 to the outer peripheral side of the annular portion 21.

Therefore, the lubricant oil entering the oil groove 25 is restrained from flowing out to the outer peripheral side of the resin thrust washer 20 by the oil stopper wall 28. Therefore, an oil film of lubricating oil can be easily formed between the surface side of the resin thrust washer 20 where the oil groove 25 exists and another member (the counter member C1, C2, or another thrust washer). Therefore, the sliding load can be reduced between the surface side of the resin thrust washer 20 where the oil groove 25 exists and another member (the opposing member C1, C2, or another thrust washer).

Further, by providing a plurality of thrust washers, sliding is possible between the thrust washers. Therefore, the rotation difference between the thrust washer and the opposing members C1, C2 can be relatively reduced, or a state without the rotation difference can be realized, and the sliding load can be reduced.

In the present embodiment, the oil groove 25 is provided with a first oil groove 25a inclined toward one side with respect to the radial direction of the annular portion 21 and a second oil groove 25b inclined toward the other side different from the one side with respect to the radial direction of the annular portion 21, and the first oil groove 25a and the second oil groove 25b are connected at the opening portion 27.

As described above, the first oil groove 25a and the second oil groove 25b are inclined to the one side and the other side, respectively, with the radial direction therebetween. Therefore, an oil film of lubricating oil can be easily formed between the resin thrust washer 20 and another member (the counter member C1, C2, or another thrust washer) on the surface side of the resin thrust washer 20 on which the oil grooves 25 are present, regardless of whether the resin thrust washer 20 rotates clockwise or counterclockwise. Therefore, the sliding load can be reduced between the surface side of the resin thrust washer 20 where the oil groove 25 exists and another member (the opposing member C1, C2, or another thrust washer) regardless of the rotational direction of the resin thrust washer 20.

In the present embodiment, at least 1 metal thrust washer 50 made of metal is provided in the thrust washer. Here, the metal thrust washer 50 can be thinner than the resin thrust washer 20. Therefore, the overall thickness of the combined thrust washer 10 can be reduced.

In the present embodiment, three thrust washers are provided, and smooth sliding

surfaces

26 and 203 without oil grooves 25 are provided on the front and rear surfaces of the annular portion 21 of the thrust washer disposed at the center of the arrangement of the three thrust washers.

Even with such a configuration, the sliding load can be reduced.

In the present embodiment, the thrust washers disposed on one end side and the other end side of the array of thrust washers are resin thrust washers 20. Meanwhile, oil grooves 25 are provided on the surfaces of the resin thrust washers 20 disposed on the one end side and the other end side of the array, which faces the thrust washer disposed at the center of the array.

Therefore, since the surfaces of the resin thrust washer 20 on which the oil grooves 25 are present are configured to face the smooth sliding

surfaces

26 and 203 of the thrust washer on which the oil grooves 25 are not formed, lubricating oil can be supplied from the oil grooves 25, and an oil film can be formed satisfactorily on the surfaces of the smooth sliding

surfaces

26 and 203. This reduces the sliding load between the surface of the resin thrust washer 20 where the oil groove 25 is present and the smooth sliding

surfaces

26 and 203 of the thrust washer where the oil groove 25 is not formed.

In the present embodiment, smooth sliding

surfaces

26 and 203 in a state where the oil grooves 25 are not formed are provided on the opposite side surfaces of the resin thrust washers 20 disposed on the one end side and the other end side of the array, which faces the thrust washer disposed at the center of the array.

Therefore, the oil groove 25 does not exist between the opposing members C1 and C2 and the resin thrust washer 20 disposed on the one end side and the other end side of the thrust washer. Therefore, in the opposing members C1 and C2, when the roughness of the surfaces of the thrust washers facing the resin thrust washers 20 disposed on the one end side and the other end side of the array is large, the resin thrust washers 20 on the one end side and the other end side rotate together without sliding with respect to the opposing members C1 and C2. Therefore, the lubricating oil is supplied from the oil groove 25 between the surface side of the resin thrust washer 20 on the one end side and the other end side where the oil groove 25 exists and the smooth sliding

surface

26, 203 of the thrust washer disposed at the center. This enables a good oil film to be formed on the surface of the smooth sliding surface 26. Therefore, the sliding load can be reduced between these surfaces.

In the present embodiment, the thrust washer disposed at the center of the three thrust washers is a metal thrust washer 50 made of metal. Therefore, the overall thickness of the combined thrust washer 10 can be reduced. Lubricating oil is supplied from the oil groove 25 between the sliding surface 203 of the metal thrust washer 50 and the surface side of the resin thrust washer 20 on which the oil groove 25 is present on the one end side and the other end side. This enables a good oil film to be formed on the surface of the smooth sliding surface 26. Therefore, the sliding load can be reduced between these surfaces.

In the present embodiment, the surrounding portion 111 surrounded by the first oil groove 25a, the second oil groove 25b, and the opening portion 27 is recessed from the sliding surface 26 in the thickness direction. Further, an oil bank 109 for partitioning the surrounding portion 111 and the first oil groove 25a, and the surrounding portion 111 and the second oil groove 25b are provided therebetween, and the position of the oil bank 109 in the thickness direction is set to be approximately the same as that of the sliding surface 26.

Therefore, the surrounding portion 111 is recessed from the oil bank portion 109. Therefore, the oil bank 109 may sometimes slide directly with respect to the other component (the opposing member C1, C2, or other thrust washer), but the surrounding portion 111 does not slide directly with respect to the other component (the opposing member C1, C2, or other thrust washer). On the other hand, in the surrounding portion 111, the lubricating oil flows in through the oil groove 25, and the lubricating oil is stored in the surrounding portion 111. Therefore, the sliding load between the resin thrust washer 20 and another member (the opposing member C1, C2, or another thrust washer) can be further reduced.

[6. modification ]

While the embodiments of the present invention have been described above, the present invention can be modified in various ways. This is explained below.

In the above embodiment, the oil grooves 25 having the same shape are provided on the front and back surfaces of 1 resin thrust washer 20. However, oil grooves 25 having different shapes may be formed on the front and back surfaces of 1 resin thrust washer 20. Further, at least one oil groove 25 formed in the resin thrust washer 20 constituting the composite thrust washer 10 may be formed in a shape different from that of other oil grooves. For example, the resin thrust washer 20, the metal thrust washer 50, or the opposing members C1 and C2 may be adapted to the surface roughness of the surface opposing the sliding surface 26 where the oil groove 25 is present, and the shape of the oil groove 25 may be changed to supply a proper amount of lubricating oil.

In the resin thrust washer 20 according to the above-described 1 to 5 th structural examples, 7 th structural example, and 8 th structural example, the communication oil groove 113 recessed from the sliding surface 26 may be provided in the same manner as the communication oil groove 113 of the resin thrust washer 20 according to the 6 th structural example. Fig. 28 shows an example of such a structure. In fig. 28, the communication oil grooves 113 are provided only in the same number as the combination of the first oil groove 25a and the second oil groove 25b in the V-shape. However, the number of the communicating oil grooves 113 may be more or less than the number of the sets of the first oil grooves 25a and the second oil grooves 25b in the V-shape. In the configuration shown in fig. 28, the communication oil groove 113 is provided linearly along the radial direction. However, the communication oil groove 113 may be provided not in the radial direction but in a manner inclined with respect to the radial direction. The communication oil groove 113 may be curved instead of being linear.

When such a communicating oil groove 113 is provided, the flow rate of the lubricating oil passing through the communicating oil groove 113 toward the outer diameter side can be increased. Therefore, the resin thrust washer 20 can have excellent heat dissipation properties.

Claims

1. A combined thrust washer is provided with a plurality of thrust washers having annular portions surrounding through-holes,

the composite thrust washer is characterized in that,

the thrust washer is provided with at least one resin thrust washer made of a material containing resin,

in the resin thrust washer, sliding surfaces that slide relative to other members are provided on the front and back surfaces of the annular portion, and an oil groove that is recessed from the sliding surfaces and into which lubricating oil flows is provided on at least one of the front and back surfaces,

an opening portion recessed with respect to the sliding surface is present in an inner peripheral end portion of the annular portion in the oil groove, and the lubricating oil enters the oil groove from the through hole side due to the presence of the opening portion,

and an oil stop wall provided at an outer peripheral end portion of the annular portion so as to partition the oil groove from an outer side of the annular portion, the oil stop wall being provided at a position in a thickness direction to be substantially equal to the sliding surface,

the presence of the oil stopper suppresses the lubricating oil that has entered the oil groove from flowing out to the outer peripheral side of the annular portion.

2. The composite thrust washer of claim 1,

the oil groove is provided with a first oil groove that is inclined toward one side with respect to a radial direction of the annular portion, and a second oil groove that is inclined toward the other side different from the one side with respect to the radial direction of the annular portion,

the first oil groove and the second oil groove are connected at the opening.

3. The composite thrust washer of claim 1,

the thrust washer is provided with at least one metal thrust washer made of metal.

4. The composite thrust washer of claim 2,

5. The composite thrust washer of claim 1 or 3,

the number of the thrust washers is three,

the thrust washer is provided with a smooth sliding surface on which the oil grooves are not formed on the front and back surfaces of the annular portion of the thrust washer disposed at the center of the arrangement of the three thrust washers.

6. The composite thrust washer of claim 2 or 4,

the number of the thrust washers is three,

7. The composite thrust washer of claim 5,

the thrust washers disposed on one end side and the other end side of the array are the resin thrust washers,

and the oil grooves are provided on surfaces of the resin thrust washers disposed on one end side and the other end side of the array, the surfaces facing the thrust washer disposed at the center of the array.

8. The composite thrust washer of claim 6,

the thrust washers disposed on one end side and the other end side of the array of the three thrust washers are the resin thrust washers,

9. The composite thrust washer of claim 7,

a smooth sliding surface in which the oil grooves are not formed is provided on a surface of the resin thrust washer disposed on one end side and the other end side of the array, the surface being opposite to a surface of the resin thrust washer opposing the thrust washer disposed at the center of the array.

10. The composite thrust washer of claim 8,

11. The composite thrust washer of claim 5,

the thrust washer disposed at the center of the arrangement of the three thrust washers is a metal thrust washer made of metal.

12. The composite thrust washer of claim 6,

13. The composite thrust washer of claim 7,

14. The composite thrust washer of claim 8,

15. The composite thrust washer of claim 9,

16. The composite thrust washer of claim 10,

17. The composite thrust washer of claim 2 or 4,

an enclosing portion enclosed by the first oil groove, the second oil groove, and the opening portion is recessed in a thickness direction with respect to the sliding surface,

an oil bank for partitioning the surrounding portion and the first oil groove, and an oil bank for partitioning the surrounding portion and the second oil groove are provided between the surrounding portion and the first oil groove, and the oil bank is provided at a position approximately equal to the sliding surface in the thickness direction.

18. The composite thrust washer of claim 6,

19. The composite thrust washer of claim 8,

20. The composite thrust washer of claim 10,

21. The composite thrust washer of claim 12,

22. The composite thrust washer of claim 14,

23. The composite thrust washer of claim 16,