chain guide

Abstract

The present application provides a chain guide, specifically, a chain guide (10) provided with at least one bush structure (40) for mounting a bush member (30) to a guide body (20), characterized in that the guide body (30) has: a cylindrical portion insertion hole (25) for inserting a bush cylindrical portion (31); and a back side limiting portion (26) for limiting movement of a flange portion (32) to the back side in the guide width direction, and on the guide body (30), on each bush structure (40), only on one side of the outer periphery side of the cylindrical portion insertion hole (25) when viewed in the guide width direction, a surface side limiting portion (27a) for limiting movement of the flange portion (32) to the surface side in the guide width direction is provided.

Description

Technical Field

[0001] This invention relates to a chain guide for slidingly guiding a moving chain in a timing system of an engine, etc. Background Technology

[0002] In the past, in engine timing systems and the like, chain guides that slide to guide the moving chain were typically used to stabilize the chain moving between sprockets and maintain appropriate tension.

[0003] This type of chain guide is installed on an object such as an engine assembly using a mounting screw that passes through a screw through hole formed on the guide body (see, for example, Patent Documents 1-3). However, since the guide body is made of synthetic resin while the mounting screw is made of metal, there is a problem that when the engine is running, a thermal shrinkage difference occurs between the synthetic resin guide body and the metal mounting screw due to heat. This thermal shrinkage difference causes loosening between the screw through hole and the mounting screw, resulting in a loose installation of the chain guide.

[0004] Therefore, in this type of chain guide, one of the objectives is to alleviate the problem of loosening in the installation state of the chain guide caused by this poor thermal shrinkage. In this case, a metal bushing component is sandwiched on the inner circumference of the screw through hole of the guide body.

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2017-078486

[0007] Patent Document 2: Japanese Patent Application Publication No. 2011-127741

[0008] Patent Document 3: Japanese Patent Application Publication No. 10-238604 Summary of the Invention

[0009] However, when installing this chain guide to an engine assembly, the following operation is required: while maintaining the bushing component inserted into the screw through hole of the guide body, the mounting screw inserted into the bushing component is tightened to the engine assembly, etc. This results in a decrease in work efficiency. In addition, the bushing component may fall off during the transport of the chain guide.

[0010] Therefore, the present invention is an invention that solves these problems. The technical problem to be solved is to provide a chain guide with a simple structure that improves the operability and transportability during installation.

[0011] This invention relates to a chain guide, comprising: a guide body having a guide block support portion on its upper side in the height direction for supporting a guide block, the guide block providing sliding guidance for a moving chain; and at least one bushing structure portion for mounting a bushing component onto the guide body. The invention addresses the aforementioned problem by having: a bushing cylindrical portion with a screw through hole; and a flange portion protruding from one end of the bushing cylindrical portion toward its outer periphery; the guide body having: a cylindrical portion insertion hole forming... To allow the bushing cylindrical portion to penetrate through the guide in the width direction, it is inserted from the front side to the back side in the width direction of the guide; and a back-side limiting portion restricts the movement of the flange portion to the back side in the width direction of the guide. On the guide body, on each bushing structure portion, when viewed in the width direction of the guide, a front-side limiting portion is provided only at one location on the outer periphery of the insertion hole of the cylindrical portion. The front-side limiting portion is located on the front side of the flange portion in the width direction of the guide to restrict the movement of the flange portion to the front side in the width direction of the guide.

[0012] According to one embodiment of the invention, the guide body has: a cylindrical insertion hole formed to extend through the guide width direction, allowing the bushing cylindrical portion to be inserted from the front side toward the back side in the guide width direction; and a back-side limiting portion to restrict the movement of the flange portion toward the back side in the guide width direction. Furthermore, on the guide body, on each bushing structure portion, when viewed in the guide width direction, a front-side limiting portion is provided only at one location on the outer periphery of the cylindrical insertion hole. This front-side limiting portion is located on the front side of the flange portion in the guide width direction to restrict the movement of the flange portion toward the front side in the guide width direction. Therefore, since the bushing component can be prevented from detaching from the guide body, the transportability of the chain guide can be improved, as well as the workability related to installing the chain guide on objects such as engine sets. Moreover, since only one front-side limiting portion is provided on each bushing structure portion, the ease of installation of the bushing component relative to the guide body can be improved.

[0013] According to another embodiment of the invention, since the guide body has an extension portion extending from the back side toward the front side in the guide width direction, and a front side limiting portion is formed on the front side top end of the extension portion, the extension portion can be made flexible, and thus the bushing component can be easily mounted relative to the guide body.

[0014] According to another embodiment of the invention, since the surface-side limiting portion is formed on the lower side of the cylindrical portion insertion hole in the height direction of the guide member, the surface-side limiting portion can be formed by avoiding the guide block support portion side, which is subject to more design restrictions, thus ensuring the design freedom of the surrounding structure of the surface-side limiting portion.

[0015] According to another embodiment of the invention, since the extension portion having the surface-side limiting portion on the top surface portion is formed to extend from the back side boss portion formed on the back side in the guide width direction of the support wall toward the surface side in the guide width direction, the length of the extension portion in the guide width direction can be sufficiently ensured, and the extension portion can easily have good flexibility, so the installation of the bushing component relative to the guide body can be easily achieved.

[0016] According to another embodiment of the invention, on the top surface of the extended portion, the surface limiting portion protrudes in a convex shape toward the center of the cylindrical insertion hole, and when the guide body is viewed in the guide width direction, a guide through portion extending through the guide width direction is provided at a position overlapping with the surface limiting portion. Thus, since this guide through portion can function as an oil passage for moving oil between the surface and back sides in the guide width direction, oil can be well distributed in the bushing structure portion, especially in the gap between the cylindrical insertion hole of the guide body and the bushing cylindrical portion, as well as on the extended portion with the surface limiting portion. Furthermore, when injection molding the guide body made of synthetic resin, mold release is facilitated; that is, since the guide through portion can also be used as a part for assembling a mold for forming the back side shape in the guide width direction of the convex surface limiting portion, the convex surface limiting portion can be easily and well formed, and the flexibility of the extended portion can be improved.

[0017] According to another embodiment of the invention, the flange portion has: a flange limiting portion, wherein movement of the surface side in the width direction of the guide member is limited by the surface limiting portion; and a flange small diameter portion, wherein the diameter from the center of the bushing cylindrical portion to the outer edge of the flange portion is smaller than the diameter of the flange limiting portion.

[0018] Therefore, when the bushing component is installed onto the guide body, the cylindrical part of the bushing can be inserted into the cylindrical insertion hole of the guide body while the circumferential positions of the surface limiting part and the small diameter part of the flange are aligned. Then, by rotating the bushing component and aligning the circumferential positions of the surface limiting part and the flange with the limiting part, the movement of the flange part on the surface in the guide width direction is restricted by the surface limiting part. Therefore, even if the extension is not flexible, interference between the flange part and the surface limiting part during the installation of the bushing component relative to the guide body can be avoided, thereby increasing the design freedom of the extension part and the surface limiting part.

[0019] According to another embodiment of the invention, since the guide body has a rotation limiting portion, the rotation limiting portion can restrict the rotation of the flange portion while the movement of the flange portion on the surface side in the guide width direction is restricted by the surface limiting portion. Therefore, after the bushing component is installed on the guide body, the accidental dislodgement of the bushing component caused by accidental rotation of the bushing component can be suppressed.

[0020] According to another embodiment of the invention, since the reinforcing rib of the guide body has a peripheral rib, which is formed to surround the outer periphery of the flange portion when the bushing component is installed on the guide body, the guide body can be reinforced by the reinforcing rib including the peripheral rib. Moreover, since tools or the like can be prevented from hitting the flange portion of the bushing component installed on the guide body, the bushing component can be prevented from accidentally coming off the guide body. Attached Figure Description

[0021] Figure 1 This is an explanatory diagram showing the usage configuration of the chain guide according to the first embodiment of the present invention.

[0022] Figure 2 This is a three-dimensional diagram representing the chain guide.

[0023] Figure 3 This is an explanatory diagram showing the area near the bushing structure after the bushing components have been installed.

[0024] Figure 4 This is an explanatory diagram showing the bushing assembly after it has been removed.

[0025] Figure 5 This is an explanatory diagram showing the state after the bushing component has been removed.

[0026] Figure 6 This is an explanatory diagram showing the state of the bushing component after it has been removed, viewed from the opposite side.

[0027] Figure 7 This is an explanatory diagram showing a cross-section of the area near the bushing structure.

[0028] Figure 8 It is a cross-sectional view showing the state after the chain guide is installed onto the object.

[0029] Figure 9 This is an explanatory diagram showing the area near the bushing structure in the second embodiment.

[0030] Figure 10 This is an explanatory diagram showing the bushing assembly after it has been removed.

[0031] Figure 11 This is an explanatory diagram showing a modified example of the second embodiment.

[0032] Figure 12 This is an explanatory diagram showing the bushing assembly after it has been removed.

[0033] Figure 13 This is an explanatory diagram showing the vicinity of the bushing structure in the third embodiment.

[0034] Figure 14This is an explanatory diagram showing the bushing assembly after it has been removed.

[0035] Figure 15 This is an explanatory diagram showing the state of the bushing component after it has been removed, viewed from the opposite side.

[0036] Figure 16 This is an explanatory diagram showing a cross-section of the area near the bushing structure.

[0037] Symbol Explanation

[0038] 10-Chain guide; 20-Guide body; 21-Guide block support; 22-Support wall; 23-Reinforcing rib; 23a-Bottom rib; 23b-Connecting rib; 23c-Peripheral rib; 24-Back side boss; 25-Cylindrical insertion hole; 25a-Screw hole; 26-Back side limiting part; 27-Extended part; 27a-Surface limiting part; 28-Through part; 29-Rotation limiting part; 30-Bushing component; 31-Bushing cylindrical part; 31a-Screw through hole; 32-Flange part; 32a-Flange limited part; 32b-Small diameter flange part; 40-Bushing structure part; CH-Chain; T;-Tensioning device; G;-Rocking guide; E;-Engine assembly (installation object); B;-Mounting screw; S1~3-Sprockets. Detailed Implementation

[0039] Hereinafter, the chain guide 10 according to the first embodiment of the present invention will be described with reference to the accompanying drawings.

[0040] like Figure 1 and Figure 8 As shown, the chain guide 10 according to the first embodiment of the present invention is used in a timing system installed in the engine compartment. It is fixed to the engine assembly E, which is the object of installation, by mounting screws B, so as to slide guide the chain CH, which is wound between sprockets S1 to 3 respectively provided on the crankshaft and camshaft. In addition, Figure 1 In the timing system shown, in addition to the chain guide 10, a rocking guide G is also provided as a guide for sliding the moving chain CH. The rocking guide G is supported in the engine compartment by a rocking shaft and is pressed towards the chain CH by the tensioning device T.

[0041] like Figure 2 and Figure 3 As shown, the chain guide 10 includes: a guide body 20, which is fixed on the engine unit E, and a guide block support portion 21 on the upper side in the height direction of the guide for supporting a guide block (not shown), the guide block slidingly guiding the moving chain CH; and at least one (two in this embodiment) bushing structure portion 40 for mounting the bushing component 30 onto the guide body 20.

[0042] The guide body 20 is formed from synthetic resin or the like through injection molding or other methods, such as... Figures 2-4 As shown, it includes: a guide block support portion 21 supporting a guide block (not shown); a support wall 22 supporting the guide block support portion 21 from the lower side; a reinforcing rib 23 protruding from the side of the support wall 22 in the guide width direction; a back side boss portion 24 formed on the back side of the support wall 22 in the guide width direction; a cylindrical portion insertion hole 25 formed to penetrate in the guide width direction so that the bushing cylindrical portion 31 of the bushing member 30 is inserted from the front side to the back side in the guide width direction; a back side limiting portion 26; an extension portion 27 having a front side limiting portion 27a; and a guide through portion 28 penetrating in the guide width direction.

[0043] The guide block support 21 is the part that supports the guide block (not shown) mounted on the guide body 20, such as... Figure 7 and Figure 8 As shown, the two sides of the guide member in the width direction protrude further outward than the support wall 22 in the width direction of the guide member.

[0044] like Figure 2 and Figure 7 As shown, the support wall 22 is a flat plate-shaped part formed from the bottom of the guide block support part 21 downwards, and is configured to be orthogonal to the width direction of the guide.

[0045] like Figure 2 and Figure 4 As shown, the reinforcing rib 23 has: a bottom rib 23a, formed along a portion of the lower edge of the support wall 22; and a connecting rib 23b, which connects the guide block support portion 21 and the bottom rib 23a in the guide height direction.

[0046] like Figure 3 and Figure 4 As shown, when the bushing component 30 is installed onto the guide body 20, a portion of the connecting rib 23b can function as a peripheral rib 23c, which is formed to surround a portion of the outer periphery of the flange 32.

[0047] like Figure 6 As shown, the back-side boss 24 is a portion formed on the back side of the support wall 22 in the guide width direction. In this embodiment, it is formed by protruding from the support wall 22 and the reinforcing rib 23 (bottom rib 23a) toward the back side in the guide width direction.

[0048] like Figure 4 and Figure 6 As shown, the cylindrical insertion hole 25 is formed through the guide body 20 in the guide width direction. In this embodiment, it is formed to penetrate the support wall 22 and the back boss portion 24 in the guide width direction.

[0049] like Figure 4 and Figure 7 As shown, the back-side limiting part 26 is located on the back side of the flange part 32 in the guide width direction after the bushing part 30 is installed onto the guide body 20, and restricts the movement of the flange part 32 on the back side in the guide width direction. In this embodiment, a part of the support wall 22 functions as the back-side limiting part 26.

[0050] like Figure 5 and Figure 6 As shown, the extension portion 27 is formed to extend from a part of the guide body 20 from the back side toward the front side in the guide width direction. In this embodiment, it is formed to extend from the lower end of the back boss portion 24, passing under the guide body 20 (support wall 22 and bottom rib 23a) and toward the front side in the guide width direction.

[0051] The extension 27 is positioned at a predetermined distance downward from the guide body 20 (support wall 22 and bottom rib 23a), is flexible, and is configured to be movable relative to the center of the cylindrical insertion hole 25 in the approach and departure directions (in this embodiment, the guide height direction).

[0052] On the guide body 20, such as Figure 3 As shown, on each bushing structure 40, when viewed in the guide width direction, a surface limiting part 27a is provided only on the outer periphery of the cylindrical insertion hole 25. The surface limiting part 27a is located on the surface of the (engaging) flange 32 in the guide width direction to limit the movement of the flange 32 on the surface of the guide width direction.

[0053] In other words, only one surface-side limiting part 27a is provided on each bushing structure part 40. In this embodiment, since there are two bushing structure parts 40, a total of two surface-side limiting parts 27a are provided on the chain guide 10.

[0054] like Figure 4 As shown, in this embodiment, a convex surface limiting portion 27a is formed on the top surface portion of the extension portion 27, protruding in a convex shape toward the center side (the upper side in this embodiment) of the cylindrical insertion hole 25.

[0055] like Figure 4 As shown, the surface-side limiting portion 27a has an inclined portion on the side of the center side (the upper side in this embodiment) of the cylindrical portion insertion hole 25. The inclined portion is inclined in such a way that it approaches the center side (the upper side in this embodiment) of the cylindrical portion insertion hole 25 as it moves toward the back side in the width direction of the guide member.

[0056] like Figure 4 As shown, the surface-side limiting portion 27a (and the extension portion 27) is formed on the lower side of the cylindrical portion insertion hole 25 in the guide height direction.

[0057] like Figure 4 and Figure 6 and Figure 7 As shown, the guide penetrating portion 28 is located at a position overlapping with the surface limiting portion 27a when viewed in the guide width direction, in other words, on the upper side of the extension portion 27 (the center side of the cylindrical portion insertion hole 25), and penetrating the guide body 20 in the guide width direction.

[0058] In other words, the guide through portion 28 is formed such that when viewed from the back side in the width direction of the guide, the entire convex surface restriction portion 27a can be observed through the guide through portion 28.

[0059] In this embodiment, the through hole penetrating the back side boss portion 24 in the width direction of the guide and the through groove formed on the lower end of the support wall 22 and the bottom rib 23a in the width direction of the guide constitute the guide through portion 28.

[0060] Bushing component 30 is made of metal such as iron, such as Figure 4 As shown, it has: a cylindrical bushing cylindrical portion 31; and an annular plate-shaped flange portion 32, which protrudes from one end of the bushing cylindrical portion 31 toward the outer periphery of the bushing cylindrical portion 31.

[0061] like Figure 7 and Figure 8 As shown, a portion of the bushing cylindrical portion 31 is disposed within the cylindrical portion insertion hole 25 and has a screw through hole 31a for allowing the mounting screw B (the shaft portion) to pass through.

[0062] like Figure 3 and Figure 7 As shown, when the bushing component 30 is installed onto the guide body 20, a portion of the outer peripheral side of the flange portion 32 can function as a flange limiting portion 32a that restricts the movement of the surface side in the width direction of the guide by means of the surface limiting portion 27a.

[0063] like Figure 3 As shown, with the bushing component 30 installed onto the guide body 20, the outer periphery of the flange portion 32 is surrounded by the guide block support portion 21 and the peripheral rib 23c, except for the lower side in the guide height direction. In other words, the bottom rib 23a is not formed on the lower side of the flange portion 32.

[0064] In addition, such as Figure 7 and Figure 8As shown, when the bushing component 30 is installed onto the guide body 20, the flange portion 32 is located further inward than the peripheral rib 23c (the outer edge of the guide width direction) in the guide width direction.

[0065] In the first embodiment described above, by Figure 3 and Figure 4 It is understood that when the bushing component 30 is installed on the guide body 20, the flange portion 32 of the bushing component 30, which is close to the guide body 20, presses the extension portion 27, which has the surface limiting portion 27a formed, in the direction away from the center of the cylindrical portion insertion hole 25 (the lower side in the guide height direction), so that it flexes and moves. At the same time, the bushing cylindrical portion 31 of the bushing component 30 is inserted into the cylindrical portion insertion hole 25 of the guide body 20 in the direction of the back of the guide width direction.

[0066] In addition, such as Figure 8 As shown, the chain guide 10 is configured such that, while facing away from the mounting object, i.e., the engine assembly E, in the guide width direction of the guide body 20, the bushing cylindrical portion 31 of the bushing member 30 abuts against the engine assembly E, and is fixed to the engine assembly E by mounting screws B inserted into the screw through holes 31a of the bushing member 30. Figure 8 As shown, with the chain guide 10 fixed on the engine assembly E, the head of the mounting screw B is in contact with the flange portion 32.

[0067] Next, based on Figures 9-12 The chain guide 10 according to the second embodiment of the present invention will be described. Here, in the second embodiment, except for a few components, since it is exactly the same as the first embodiment described above, the description of the components other than the differences is omitted.

[0068] First, although Figure 4 As shown in the first embodiment described above, the case where the flange portion 32 of the bushing member 30 is formed into an annular plate shape (a circular plate shape with a hole in the center) has been explained. However, in the second embodiment, as... Figure 9 and Figure 10 As shown, the flange portion 32 is formed to cut off a portion of the annular plate.

[0069] Therefore, on the flange portion 32 of the second embodiment, as Figure 9 and Figure 10 As shown, it includes: a flange limiting portion 32a, which restricts the movement of the surface side in the width direction of the guide member by a surface limiting portion 27a; and a flange small diameter portion 32b, the diameter of which extends from the center of the bushing cylindrical portion 31 to the outer edge of the flange portion 32 is smaller than the diameter of the flange limiting portion 32a.

[0070] In the second embodiment described above, when the bushing component 30 is installed on the guide body 20, such as Figure 10 As shown, with the circumferential positions of the surface limiting portion 27a of the guide body 20 and the small diameter portion 32b of the flange portion 32 aligned, the bushing cylindrical portion 31 of the bushing member 30 is inserted into the cylindrical portion insertion hole 25 of the guide body 20, facing the back side in the width direction of the guide. At this time, the flange portion 32 (the small diameter portion 32b) is formed such that even if the extension portion 27 is not bent and the surface limiting portion 27a is not moved, the flange portion 32 will not interfere with the surface limiting portion 27a.

[0071] Subsequently, by rotating the bushing component 30 around the bushing cylindrical portion 31, it becomes... Figure 9 In the state shown, the surface limiting portion 27a of the guide body 20 and the flange of the bushing member 30 are aligned in the circumferential position by the limiting portion 32a, thereby forming a state in which the movement of the flange portion 32 in the guide width direction of the surface is restricted by the surface limiting portion 27a.

[0072] In this second embodiment, as a variation, such as Figure 11 and Figure 12 As shown, a rotation limiting part 29 can also be provided on the guide body 20. This rotation limiting part 29 can limit the rotation of the flange portion 32 (with the center of the bushing cylindrical portion 31 as the rotation center) while the movement of the flange portion 32a towards the surface side in the guide width direction is limited by the surface limiting part 27a. Figure 11 and Figure 12 In the example shown, the rotation limiting part 29 is configured as a convex portion formed on the side of the support wall 22 in the guide width direction. The rotation limiting part 29 is formed in a position facing the outer edge of the small diameter portion 32b of the flange after the bushing member 30 is installed onto the guide body 20.

[0073] Next, based on Figures 13-16 The chain guide 10 according to the third embodiment of the present invention will be described. Here, in the third embodiment, except for a few components, since it is exactly the same as the first embodiment described above, the description of the components other than the differences is omitted.

[0074] First, although in the first embodiment described above, such as Figure 4 As shown, the case where the surface-side limiting portion 27a (and the extension portion 27) of the guide body 20 is formed at the position below the cylindrical portion insertion hole 25 in the guide height direction has been described. However, in the third embodiment, as... Figures 13-16 As shown, the surface-side limiting portion 27a (and the extension portion 27) is formed on the upper side of the cylindrical portion insertion hole 25 in the guide height direction.

[0075] If specifically explained, in the third embodiment, such as Figure 13 and Figure 14 As shown, an extension portion 27 is formed protruding above the cylindrical insertion hole 25 in the height direction of the guide member, extending from the side of the support wall 22 toward the surface in the width direction of the guide member.

[0076] Furthermore, the surface-side limiting portion 27a is formed such that it protrudes in a convex shape on the top surface portion of the extension portion 27 toward the center side (the lower side in this embodiment) of the cylindrical portion insertion hole 25.

[0077] Furthermore, in the third embodiment, such as Figure 13 and Figure 14 As shown, the guide through portion 28 is also formed on the upper side of the cylindrical insertion hole 25. Specifically, when viewed in the guide width direction, it is formed on the lower side of the extension portion 27 (the center side of the cylindrical insertion hole 25) at the position overlapping with the surface restriction portion 27a, that is, on the lower side of the extension portion 27, through the guide body 20 in the guide width direction.

[0078] Furthermore, the specific formation positions of the surface-side limiting portion 27a (and the extension portion 27) and the guide through portion 28 of the guide body 20 are not limited to the lower side position of the cylindrical portion insertion hole 25 in the first embodiment and the upper side position of the cylindrical portion insertion hole 25 in the third embodiment, but can be any position on the outer periphery of the cylindrical portion insertion hole 25.

[0079] While the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments. Various design changes can be made without departing from the scope of the claims.

[0080] For example, the components of the above-described multiple embodiments and variations can be arbitrarily combined to form the chain guide 10.

[0081] Furthermore, although the above embodiment describes the case where the chain guide 10 is installed in an engine with a timing system, it is not limited to this and can be applied to a wide variety of machines.

[0082] Furthermore, not limited to chain CH transmission mechanisms, chain guide 10 can also be applied to similar transmission mechanisms such as belts and ropes, and can be used in various industrial fields.

[0083] Furthermore, although the above embodiment describes the case where the guide block (not shown) and the guide body 20 are set separately and the guide block (not shown) is mounted on the guide body 20, it is also possible to set the guide block (not shown) as an integral part on the guide body 20.

[0084] Furthermore, depending on factors such as elasticity, frictional resistance, rigidity, durability, formability, and cost, the materials of the guide body 20 and the guide block (not shown) can be selected from well-known suitable materials, with synthetic resin materials being particularly preferred.

[0085] Furthermore, although the bushing component 30 can be made of a suitable metal material depending on factors such as rigidity, durability, formability, and cost, it is preferable to form the bushing component 30 with the same metal material as the mounting screw B.

[0086] Furthermore, although in the above embodiments, such as Figure 2 As shown, the case where the chain guide 10 has bushing structure portions 40 for mounting the bushing member 30 to the guide body 20 at two locations located apart in the longitudinal direction of the guide has been described. However, the number of bushing structure portions 40 is not limited to this; it is sufficient to provide bushing structure portions 40 at one or more locations. Furthermore, Figure 2 The symbol 25a shown represents a screw hole formed through the guide body 20 in the width direction of the guide to allow the mounting screw B to pass through. Furthermore, in Figure 2 In the illustration, the left bushing structure 40 among the two bushing structure parts 40 is shown with the bushing component 30 removed.

[0087] Furthermore, although the chain guide 10 is configured as a fixed guide fixed to the engine assembly E in the above embodiment, it can also be configured as a rocking guide G supported in the engine compartment by a rocking shaft. Additionally, when configuring the chain guide 10 as a rocking guide G, only one bushing structure portion 40 for mounting the bushing component 30 to the guide body 20 is required. This bushing component 30 has a screw through hole 31a for inserting a mounting shaft (rocking shaft).

Claims

1. A chain guide comprising: a guide body having a guide block support portion on its upper side in the height direction for supporting a guide block, the guide block providing sliding guidance for a moving chain; and at least one bushing structure portion for mounting a bushing component onto the guide body, characterized in that, The bushing component has: a bushing cylindrical portion having a screw through hole; and a flange portion protruding from one end of the bushing cylindrical portion toward the outer periphery of the bushing cylindrical portion. The guide body has: a cylindrical insertion hole formed to extend through the guide in the width direction, allowing the bushing cylindrical portion to be inserted from the front side toward the back side in the width direction of the guide; and a back-side limiting portion to restrict the movement of the flange portion toward the back side in the width direction of the guide. On the guide body, on each of the bushing structures, when viewed in the guide width direction, a surface-side limiting portion is provided only at one location on the outer periphery of the cylindrical insertion hole. This surface-side limiting portion is located on the surface of the flange portion in the guide width direction to restrict the movement of the flange portion on its surface in the guide width direction. The guide body has: a support wall that supports the guide block support portion from below; and a back-side boss formed on the back side of the support wall in the guide width direction. The cylindrical insertion hole is formed to penetrate the support wall and the back-side boss portion in the width direction of the guide member. The guide body has an extension portion that extends from the back side boss portion toward the surface in the width direction of the guide. The surface-side limiting portion is formed on the top surface portion of the extended portion. The extension is formed to extend from the lower end of the back boss portion through the lower side of the guide body and toward the surface side in the width direction of the guide. The extension is disposed at a position that is a predetermined distance away from the lower side of the guide body, and is formed to be flexible and movable relative to the center of the cylindrical portion insertion hole in the approach and departure directions.

2. The chain guide according to claim 1, characterized in that, The surface-side limiting portion is formed on the lower side of the cylindrical portion insertion hole in the height direction of the guide.

3. The chain guide according to claim 1 or 2, characterized in that, The conductor body is formed of synthetic resin. The guide body has an extension that extends from a portion of the guide body from the back side toward the front side in the width direction of the guide. On the top surface of the extended portion, the surface-side limiting portion protrudes in a convex shape toward the center of the insertion hole of the cylindrical portion. When viewed in the width direction, the guide body has a guide through portion that extends through the width direction at a position overlapping with the surface limiting portion.

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