Chain drive system

Abstract

The present application aims to provide a chain transmission system which can reduce the sliding resistance of a chain and a guide block, suppress the increase in the sliding resistance over time, and reduce the wear of the guide block. The chain transmission system (100) of the present application includes a chain (130) having a plurality of chain plates (131, 135), a plurality of sprockets (101, 102) for wrapping the chain (130), and one or more guides (105, 110) each having a guide block (106, 111) with a chain moving surface (113) and serving to guide the chain (130) in the presence of lubricating oil. At least one of the plurality of chain plates (131, 135) is configured to have a lubricating region (145) in which a solid lubricant (P) is held.

Description

Technical Field

[0001] The present invention relates to a chain drive system comprising: a chain having multiple chain plates; multiple sprockets for winding the chain; and one or more guide members for slidingly guiding the chain, wherein the guide members are integrally or separately provided with guide blocks having a chain moving surface. Background Technology

[0002] In the past, in order to stabilize the chain moving between sprockets and maintain appropriate tension, a chain drive system was typically used, which has a guide for guiding the moving chain, and the guide has a guide block that slides to guide the chain, either integrally or separately.

[0003] For example, in chain drive systems of timing systems in internal combustion engines used in automobiles, it is necessary to simultaneously reduce the sliding resistance between the chain and the guide blocks and the wear of the guide blocks, considering factors such as noise reduction and reduced driving force loss. In light of this, and assuming the chain is made of metal and the guide blocks are made of resin, and that lubricant is supplied between the chain and guide blocks during use, and that the system is exposed to high temperatures, various countermeasures have been taken, including research on the shape and material of the chain and guide blocks, and the application of surface treatments.

[0004] However, for example, if the shape of the chain and guide block is changed to reduce the sliding resistance between the chain and the guide block, the contact area between the chain and the guide block becomes smaller, and therefore the wear of the guide block will increase under higher tension conditions.

[0005] On the other hand, if the shape of the chain and guide block is changed in a way that reduces the wear of the guide block, the contact area between the chain and the guide block will increase, and thus the sliding resistance between the chain and the guide block will increase.

[0006] Studying only the shape of the chain and guide block makes it difficult to simultaneously solve the trade-off problem of reducing the sliding resistance between the chain and guide block and reducing the wear of the guide block.

[0007] In addition, a technique was proposed to pre-treat the chain moving surface on the guide block to achieve a wear reduction effect on the guide block (see Patent Document 1).

[0008] like Figure 10 As shown, Patent Document 1 describes a technique in which a ceramic material-coated film 318 is formed on the surface 314 of a guide block body 312 made of synthetic resin, thereby forming a chain moving surface 313.

[0009] Patent documents

[0010] Patent Document 1: Japanese Patent Application Publication No. 2000-266141 Summary of the Invention

[0011] Furthermore, as shown in Patent Document 1, it is believed that surface treatment of the chain moving surface 313 of the guide block 311 can reduce initial wear. However, due to the sliding between the chain 130 and the guide block 311, the sprayed film 318 undergoes wear over time, and the wear powder of the sprayed film 318 is quickly discharged by the lubricating oil. Therefore, a sustained wear reduction effect and a sliding resistance reduction effect cannot be expected.

[0012] Furthermore, in Patent Document 1, the effects of reduced sliding resistance and reduced wear are only achieved on the surface of the guide block body 312 where surface treatment is performed. For example, as... Figure 11 As shown, the sprayed coating 318 wears down due to the sliding of the inner connecting plate 131, outer connecting plate 135, and guide block 311 of the chain 130. This causes the exposed surface 314 of the guide block body 312 and the wall surface 315, which is re-formed on the guide block body 312 and slidably contacts the chain 130 due to further wear. Consequently, the metal chain 130 and the resin portion of the guide block 311 slide, preventing the reduction of sliding resistance and wear. Furthermore, even on the side surface 317 of the guide wall portion 316 at the width end of the chain moving surface 313, the metal chain 130 and the resin portion of the guide block 311 slide, again preventing the reduction of sliding resistance and wear.

[0013] This invention is made to solve the problems of known chain drive systems. The technical problem to be solved is to provide a chain drive system that reduces the sliding resistance between the chain and the guide block while suppressing the increase of sliding resistance over time, and can also reduce the wear of the guide block.

[0014] This invention relates to a chain drive system comprising: a chain having multiple chain plates; multiple sprockets wound around the chain; and one or more guide members for slidingly guiding the chain in the presence of lubricating oil. The guide members are integrally or separately equipped with guide blocks having a chain moving surface. At least one of the multiple chain plates has a lubrication area containing a particle-like solid lubricant. The lubrication area is formed by a shot-peened hardened layer or shot-peened layer that mechanically adheres the solid lubricant to at least one of the multiple chain plates. The solid lubricant is configured to detach from the lubrication area and move to adhere to the chain moving surface by sliding between the chain plates and the guide blocks, thereby forming a friction film on the chain moving surface due to additive components of the lubricating oil. This solves the aforementioned problems.

[0015] According to the chain drive system of this technical solution 1, since the solid lubricant that falls off the surface of the lubrication area of ​​the chain plate due to the sliding between the chain and the guide block adheres to and remains in the chain sliding contact area of ​​the guide block, the lubrication effect of the solid lubricant itself can be obtained in the chain sliding contact area including the chain moving surface. Furthermore, since the solid lubricant gradually falls off the surface of the lubrication area of ​​the chain plate due to the sliding between the chain and the guide block, a continuous supply of solid lubricant can be provided to the guide block. Therefore, while significantly reducing the sliding resistance between the chain and the guide block, the increase in sliding resistance over time is suppressed, and the wear of the guide block is reduced.

[0016] Furthermore, according to the chain drive system involved in this technical solution 1, even under high contact surface pressure conditions where the wear of the guide block would increase in any existing chain drive system, the wear of the guide block can be reduced. Therefore, the chain and guide block can be made into shapes that reduce the contact area between the chain plate and the guide block, thereby reducing the sliding resistance between the chain and the guide block, thus achieving a high degree of design freedom.

[0017] According to the structure described in technical solution 2, solid lubricant can be reliably retained by embedding it in a guide block typically made of resin. Furthermore, through the sliding of the chain and the guide block, a friction film derived from the additive components of the lubricant can be promoted in the chain sliding contact area where the solid lubricant is retained. Therefore, the desired lubrication effect of the solid lubricant can be reliably obtained, along with the lubrication effect of the friction film, and further, the effects of reduced sliding resistance and reduced wear can be reliably achieved.

[0018] According to the structure described in technical solution 3, the solid lubricant can be reliably moved and adhered to the chain sliding contact area on the chain moving surface by sliding between the chain and the guide block.

[0019] According to the structures described in technical solutions 4 to 6, even on the new wall surface formed on the guide block due to wear and the chain moving surface side of the guide wall provided at the width direction end of the chain moving surface, the solid lubricant can be moved and adhered by the sliding of the chain and the guide block. Therefore, it is possible to prevent the chain, which is usually made of metal, from sliding directly with the guide block, which is usually made of resin, and to effectively prevent the increase of sliding resistance. Attached Figure Description

[0020] Figure 1 This is an overall diagram of a chain drive system according to one embodiment of the present invention.

[0021] Figure 2 This is a perspective view showing the appearance of the guide block according to one embodiment of the present invention.

[0022] Figure 3This is a perspective view showing a portion of a chain according to one embodiment of the present invention.

[0023] Figure 4 It is a cross-sectional view that schematically represents the contact state between the chain and the guide block in the fixed guide according to one embodiment of the present invention.

[0024] Figure 5 It means Figure 4 An enlarged view of the area enclosed by the double-dotted line.

[0025] Figure 6 It is a cross-sectional view that represents the contact state between the chain and the guide block in the fixed guide when the guide block wears out.

[0026] Figure 7 This is a schematic diagram illustrating the phenomenon of solid lubricant adhering to the moving guide block due to the sliding of the chain plate and the guide block.

[0027] Figure 8 It is a patterned representation Figure 5 The cross-sectional view of the area enclosed by the double-dotted line is a diagram showing the state of the moving surface of the chain during chain drive.

[0028] Figure 9 It is a cross-sectional view that schematically represents the configuration of the guide block in the fixed guide according to other embodiments of the present invention.

[0029] Figure 10 It is a cross-sectional view that represents the contact state between the chain and the guide block in an existing chain drive system in a patterned manner.

[0030] Figure 11 It is a cross-sectional view that represents the contact state between the chain and the guide block in the fixed guide when the guide block wears out.

[0031] Symbol Explanation

[0032] 100 - Chain drive system; 101 - Drive sprocket; 102 - Driven sprocket; 105 - Swing guide rod; 106 - Guide block; 107 - Swing shaft; 110 - Fixed guide; 111, 211, 311 - Guide block; 312 - Guide block body; 113, 213, 313 - Chain moving surface; 314 - Surface; 115, 315 - Wall; 116, 316 - Guide wall; 117, 317 - Side; 318 - Spray Coating film; 120-Base component; 121-Mounting part; 225-Plate guide groove; 130-Chain; 131-Inner connecting plate; 132-Sliding contact end face; 133-Side side; 135-Outer connecting plate; 136-End face; 137-Side side; 138-Concave and convex parts; 140-Bushing; 141-Connecting pin; 142-Roller; 145-Lubrication area; 146-Surface; 147-Friction film; P-Solid lubricant; T-Tensioning device. Detailed Implementation

[0033] Example

[0034] The chain drive system according to the embodiments of the present invention will be described with reference to the accompanying drawings.

[0035] The chain drive system 100 is used in the timing system of automotive engines, such as... Figure 1 As shown, the chain 130 is wound around the drive sprocket 101 mounted on the crankshaft and two driven sprockets 102 mounted on the two camshafts respectively. The chain 130 moving between the drive sprocket 101 and the driven sprockets 102 is guided by the swing guide rod 105 and the fixed guide 110.

[0036] The swing guide rod 105 is formed from a synthetic resin material, for example by injection molding, and is integrally provided with a guide block 106 that slides and guides the moving chain 130 in the presence of lubricating oil. The guide block 106 has a chain moving surface extending in the chain moving direction.

[0037] The swing guide rod 105 is as follows: the swing shaft 107 on the drive sprocket 101 side is swingably mounted on the engine, and a specified tension is applied to the chain 130 by pressing the tensioning device T on the driven sprocket 102 side towards the chain 130 side.

[0038] The fixed guide 110 includes: a guide block 111 for slidingly guiding the moving chain 130 in the presence of lubricating oil; and a base member 120 for supporting the guide block 111 along the chain movement direction. The base member 120 has a mounting portion 121 for fixing to the mounting object, i.e., the engine block (not shown).

[0039] Guide block 111 is formed from synthetic resin material, for example by injection molding, etc. Figure 2As shown, a chain moving surface 113 extending in the chain moving direction is provided on the surface facing the engine compartment. In addition, guide wall portions 116 are formed on both outer sides of the chain moving surface 113 in the guide block width direction.

[0040] The base component 120 is formed from a metal material, such as a metal sheet, through processes such as punching and bending.

[0041] Although the chain 130 in this embodiment is configured as a roller chain, it can be any type of chain as long as the chain has a chain plate that is slidably guided by the guide blocks 106 and 111, and can also be a sleeve chain or a silent chain.

[0042] like Figure 3 and Figure 4 As shown, the chain 130 includes: multiple inner connectors that fix the two ends of a pair of cylindrical bushings 140 to bushing holes in a pair of inner connecting plates 131; multiple outer connectors that fix the two ends of a pair of connecting pins 141 to pin holes in a pair of outer connecting plates 135; and rollers 142 that are externally fitted into the bushings 140. By inserting connecting pins 141 into the bushings 140, these multiple inner connectors and multiple outer connectors are alternately connected along the length of the chain. In this embodiment, although the inner connecting plates 131 are formed to be larger than the outer connecting plates 135, they can also be formed to be the same size. Hereinafter, the inner connecting plates 131 and the outer connecting plates 135 will be collectively referred to as chain plates.

[0043] Furthermore, in the chain drive system 100 of this embodiment, all chain plates have a lubrication area 145 that holds a solid lubricant.

[0044] Also Figure 5 As shown, a lubrication area 145 is provided in the sliding contact end face 132 and side face 133 of the inner connecting plate 131 that have sliding contact with the chain moving surface 113 on the guide block 111, and in the area where the sliding contact may have sliding contact with the guide block 111 in the width direction.

[0045] Lubrication areas 145 are provided on the end face 136 and side face 137 of the chain moving surface 113 of the outer connecting plate 135 facing the guide block 111, in areas where sliding contact with the guide block 111 is possible in the width direction. The lubrication areas 145 on the outer side of the outer connecting plate 135 are provided in areas where sliding contact with the side face 117 of the guide wall portion 116 on the chain moving surface 113 side is possible.

[0046] Since lubrication areas 145 are also provided on the side 133 of the inner connecting plate 131 and the side 137 of the outer connecting plate 135, therefore... Figure 6As shown, even if the guide block 111 wears down due to sliding with the chain 130, and a new wall surface 115 is accidentally formed that may slide in contact with the inner connecting plate 131 or the outer connecting plate 135 in the width direction, the increase in sliding resistance can be effectively prevented.

[0047] like Figure 7 As shown, the lubrication zone 145 is formed by adhering particulate solid lubricant P to the chain plate. Furthermore, Figure 7 For ease of understanding, the state of the surface 146 where the chain moving surface 113 is separated from the lubrication area 145 on the inner connecting plate 131 is shown. Furthermore, although the particle size of the solid lubricant P is described in great detail, it does not represent the actual size.

[0048] As for solid lubricant P, it is not specifically limited as long as it can adsorb additive components contained in lubricating oil or react with additive components to form a friction film, but examples can be metals such as copper and aluminum or their alloys, metal oxides such as aluminum oxide, etc.

[0049] For example, the lubrication area 145 can be formed by shot peening or shot peening with a solid lubricant P as the projectile material. Preferably, the solid lubricant P is a material with a particle size in the range of, for example, 1 to 200 μm. By attaching the solid lubricant P to the chain plate in this way, the solid lubricant P adheres tightly to the chain plate through the mechanical engagement of the protrusions and recesses. Therefore, by sliding the chain plate against the guide block 111, the solid lubricant P can move from the surface of the lubrication area 145 and adhere to the chain moving surface 113 of the swing guide rod 105 and the fixed guide 110. Furthermore, since the solid lubricant P collides with the chain plate while maintaining a solid state, the solid lubricant P does not deteriorate and can maintain its original properties.

[0050] Furthermore, in the chain drive system 100 according to this embodiment, due to the sliding of the chain 130 and the guide block 111, the solid lubricant P falls off from the surface of the lubrication area 145 of the chain plate and is retained by embedding it in the chain moving surface 113 of the guide block 111, which is made of synthetic resin. Therefore, the lubricating oil supplied between the chain 130 and the guide block 111 will not be discharged to the outside, such as... Figure 8 As shown, a state can be obtained in which the friction film 147, which is derived from the additive components of the lubricating oil, is easily promoted to form. In the chain sliding contact area of ​​the guide block 111, the lubrication effect of the solid lubricant itself and the lubrication effect derived from the friction film 147 can be obtained.

[0051] Furthermore, the chain plate has fine irregularities 138 on its surface, and the solid lubricant P adheres to and remains on these irregularities 138, thus ensuring a continuous supply of solid lubricant P to the chain moving surface 113. The same lubrication effect can be achieved even on the chain moving surface of the oscillating guide 105.

[0052] Therefore, the chain drive system 100 according to this embodiment can significantly reduce the sliding resistance between the chain 130 and the guide blocks 106 and 111 while suppressing the increase of sliding resistance over time, and can also reduce the wear of the guide blocks 106 and 111.

[0053] In the embodiments described above, although all chain plates have a structure with a lubrication area 145, it is sufficient that at least one of the chain plates has a lubrication area 145. Furthermore, the lubrication area 145 does not need to be located on the side of the chain plate, but rather only needs to be located on the sliding contact surface with the moving surface of the chain.

[0054] Moreover, such as Figure 9 As shown, the guide block 211 can also have a structure in which a plate guide groove 225 extending along the chain movement direction is provided on the chain moving surface 213. In this embodiment, although the plate guide groove 225 is configured to guide the inner connecting plate 131 and the outer connecting plate 135, the specific shape of the plate guide groove is not limited to this. For example, the plate guide groove can also be formed in a way that only guides the inner connecting plate 131. In this embodiment, not only the bottom surface of the plate guide groove 225 that slides in contact with the chain plate, but also both sides of the plate guide groove 225 that contact the chain plate in the width direction can be moved and attached by the sliding of the chain 130 and the guide block 211. Therefore, it is possible to prevent the chain 130, which is made of metal, from sliding directly with the guide block 211, which is made of synthetic resin, and to effectively prevent the increase of sliding resistance.

[0055] Although the above-described embodiments envision a chain drive system for timing systems of internal combustion engines such as automobiles, they are not limited to this and can be applied to various types of machines.

[0056] Furthermore, although it is made into a chain drive system, as long as the material and sliding contact state are the same, it can be applied to similar drive systems such as belts and ropes, and can be used in various industrial fields.

Claims

1. A chain drive system, comprising: a chain having a plurality of chain plates; a plurality of sprockets around which the chain is wound; and one or more guides that slide guide the chain in the presence of lubricating oil, wherein the guide has a guide block having a chain sliding surface, and wherein at least one of the plurality of chain plates has a lubricating region in which a particulate solid lubricant is held, wherein the lubricating region is formed of a shot peening layer or a shot peening treatment layer that mechanically adheres the solid lubricant to at least one of the plurality of chain plates, wherein the solid lubricant is configured to be detached from the lubricating region by sliding of the chain plate and the guide block and to be attached to the chain sliding surface, thereby forming a friction film on the chain sliding surface due to an additive component of the lubricating oil.

2. The chain drive system according to claim 1, wherein the solid lubricant is formed of a metal or a metal oxide.

3. The chain drive system according to claim 1 or claim 2, wherein the lubricating region is provided on an end surface of the chain plate that is in sliding contact with the chain sliding surface.

4. The chain drive system according to claim 1, wherein the guide block has a wall surface that is in contact with the chain plate in a width direction, and wherein the lubricating region is provided on a side surface of the chain plate that is in sliding contact with the wall surface, wherein the wall surface includes a surface of a guide wall provided on an end portion of the chain sliding surface in the width direction, or wherein the wall surface includes both side surfaces of a groove formed on the chain sliding surface. ​ ​ ​ ​ ​ ​ ​ ​ 5. A chain drive system according to claim 4, characterised in that ​ 6. A chain drive system according to claim 4, characterised in that ​

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