Chain guide

Abstract

[Problem] To provide a chain guide that can improve transportability and workability during attachment with a simple configuration, while ensuring stable operation of the timing chain and improving durability. [Solution] The chain guide (100) is a chain guide having a guide shoe that slides and guides the chain and a chain guide body that supports the guide shoe. A compression limiter (150) is fitted into a fixing through hole (111) that penetrates in the width direction of the chain guide body (110), and has an attachment hole (151) into which an attachment bolt for attaching the chain guide to a member is inserted. A compression limiter holding mechanism is installed on a hole periphery (120) including the fixing through hole in the chain guide body or on the compression limiter to hold and maintain the compression limiter.

Description

Technology Field

[0001] The present invention relates to a chain guide comprising a guide shoe that slides and guides a chain, and a chain guide body that supports the guide shoe. Background Technology

[0002] Conventionally, in order to stabilize the chain running between sprockets and maintain the tension appropriately, it is common practice to use a chain guide equipped with a guide shoe that slides and guides the running chain.

[0003] For example, as shown in FIG. 10, there is a known timing system for an engine that drives a transmission chain (CH), such as a roller chain, which is driven continuously between sprockets (S1, S2) installed on a crankshaft and a camshaft, respectively, in an engine room (E), wherein the timing chain (CH) is driven continuously between a driving sprocket (S1) attached to a crankshaft in the engine room (E) and a pair of driven sprockets (S2) attached to a camshaft, and the timing chain (CH) is guided by a oscillating chain guide (oscillating guide) (600) and a chain guide (fixed guide) (500).

[0004] The chain tensioner (T) maintains the tension of the timing chain (CH) at an appropriate level and suppresses vibration by pressing the oscillating guide (600).

[0005] In this timing system, the fixed guide (500) is fixed within the engine room (E) by a plurality of fixed attachment bolts (Q), and the oscillating guide (600) is attached within the engine room (E) so as to be oscillating within the oscillating plane of the timing chain (CH) around the oscillating attachment bolt (P) (see, for example, References 1 to 3, etc.).

[0006] The known chain guide (oscillating guide) (600) and chain guide (fixed guide) (500) used in such a timing system are configured to include a guide shoe that slides and guides the running chain, and a chain guide body that supports and reinforces the guide shoe along the direction of the chain's running, and the chain guide body is formed of synthetic resin. Meanwhile, since the attachment bolts (P, Q) for fixing the chain guide (500, 600) to the engine room (E) which is the attachment member are made of metal, the attachment bolts (P, Q) become loose due to the difference in thermal shrinkage between the attachment bolts (P, Q) and the resin chain guide body caused by the heat generated during the operation of the timing system, and as a result, loosening occurs in the attachment state of the chain guide, and there was a problem in that stable running of the timing chain was not ensured. Prior art literature

[0008] Japanese Patent Publication No. 2017-078486, Japanese Patent Publication No. 2011-127741, Japanese Patent Publication No. 10-238604 The problem to be solved

[0009] In order to alleviate the problem of looseness in the attachment state of the chain guide caused by such thermal shrinkage difference, a metal bushing formed of the same material as the attachment bolt is interposed between the inner surface of the fixing through hole through which the attachment bolt in the chain guide is inserted and the attachment bolt, thereby mitigating the thermal shrinkage difference between the attachment bolt and the chain guide.

[0010] However, when attaching the chain guide to the engine room, which is the attachment point, the chain guide body and the metal bushing inserted into its fixing through-hole are treated as a single unit. However, there is a problem in that the metal bushing detaches during the process of inserting the metal bushing into the fixing through-hole of the chain guide body and fastening the attachment bolt to the screw hole formed on the attachment surface of the engine room, making it difficult to attach even when a worker uses both hands and causing a decrease in work efficiency. In addition, there is a risk that the metal bushing may detach during the transport of the chain guide.

[0011] The present invention aims to solve these problems by providing a chain guide that can improve transportability and workability during attachment with a simple configuration, while simultaneously ensuring stable operation of the timing chain to enhance durability. means of solving the problem

[0013] The chain guide of the present invention is a chain guide comprising a guide shoe that slides and guides a chain, and a chain guide body that supports the guide shoe.

[0014] A compression limiter is fitted and installed in a fixing through hole penetrating in the width direction of the chain guide body, the compression limiter having a mounting hole through which a mounting bolt for attaching the chain guide to a member is inserted.

[0015] The above problem is solved by installing a compression limiter retaining mechanism that retains the compression limiter on the periphery of a hole including a fixing through hole in the above chain guide body or on the above compression limiter. Effects of the invention

[0017] According to the chain guide of the present invention, a compression limiter retaining mechanism is installed in the periphery of a hole including a fixing through hole in the chain guide body or in the compression limiter itself to retain and maintain the compression limiter. Basically, since the compression limiter is interposed between the chain guide body and the attachment bolt, the difference in thermal shrinkage occurring between the attachment bolt and the chain guide body is mitigated, thereby ensuring stable operation of the timing chain and improving durability. Furthermore, during transport, the compression limiter retaining mechanism prevents the compression limiter from detaching from the chain guide body, thereby improving transportability. At the same time, when attaching to a non-attachable member, the compression limiter retaining mechanism prevents the compression limiter from detaching from the chain guide body, allowing it to be attached to the non-attachable member and improving workability during attachment.

[0018] According to the chain guide of the present invention, which has a tapered shape formed on the inner circumference of a fixing through hole such that the diameter decreases in one direction along the axial direction, when a compression limiter is inserted into the fixing through hole in the direction in which the diameter decreases, the compression limiter can be easily stored and maintained due to the tapered shape, thereby improving workability and transportability when securely attached with a simple configuration.

[0019] According to the chain guide of the present invention, which has a configuration in which a thin section is formed between the annular recess and the inner circumference of the fixing through hole at the periphery of the hole, the thin section is formed to be easily bendable so that elasticity can be obtained in the fixing through hole, so that the compression limiter is securely held in the chain guide body by the elasticity of the fixing through hole, and the detachment of the compression limiter from the chain guide body is reliably prevented, thereby further improving workability and transportability during attachment. In addition, since the function of oil retention is exerted in the annular recess, oil retention around the fixing through hole is improved, and damping performance against vibration is improved, and when the chain guide is a fixed guide, the risk of wear and breakage can be reduced, and even when the chain guide is a movable guide, the risk of wear of the sliding part is reduced and the service life can be extended by improving the lubricity of the oil.

[0020] According to the chain guide of the present invention, which is configured such that an annular portion is divided into a plurality of arc-groove-shaped portions through a bridge structure, the formation of undulation in the annular portion is suppressed by the bridge structure, thereby improving the strength of the annular portion.

[0021] According to the chain guide of the present invention, which has a configuration in which a securing portion is formed to secure the compression limiter to the periphery of a hole, the securing portion is engaged with the periphery of the hole while the compression limiter is inserted into a fixing through hole, thereby reliably preventing the compression limiter from detaching from the chain guide body and further improving workability and transportability during attachment.

[0022] According to the chain guide of the present invention, which has a structure of irregularities formed on the inner surface of a fixing through hole, friction can be caused between the irregularity structure on the inner surface of the fixing through hole and the outer surface of the attachment bolt, thereby reliably preventing the compression limiter from detaching from the chain guide body and further improving workability and transportability during attachment.

[0023] According to the chain guide of the present invention, in which the hole periphery is integrally formed with the chain guide body, the number of process steps during manufacturing can be reduced to reduce the manufacturing load, thereby enabling the manufacturing of a chain guide with high productivity. Brief explanation of the drawing

[0025] [Fig. 1] Front view showing an example of a chain guide (fixed guide). [Fig. 2] Perspective view of the hole periphery of a chain guide and a compression limiter according to the first embodiment of the present invention. [Fig. 3] Perspective cross-sectional view of the hole periphery and compression limiter of Fig. 2. [Fig. 4] Cross-sectional view of the hole periphery and compression limiter of Fig. 2. [Fig. 5] A partial cross-sectional view showing an enlarged portion of the periphery of the hole in Fig. 2. [Fig. 6] Perspective view showing another example of a fixing through hole. [Fig. 7] Partial cross-sectional view showing a modified example of the hole periphery of a chain guide according to the first embodiment of the present invention. [Fig. 8] Cross-sectional view of the hole periphery of a chain guide and a compression limiter according to a second embodiment of the present invention. [Fig. 9] Front view showing an example of a chain guide (oscillating guide). [Fig. 10] Diagram illustrating a timing system of a conventional engine. Specific details for implementing the invention

[0026] The chain guide of the present invention comprises a guide shoe for slidingly guiding a chain and a chain guide body that supports the guide shoe. A compression limiter is fitted into a fixing through hole penetrating the width direction of the chain guide body, the attachment hole into which an attachment bolt for attaching the chain guide to a member is inserted. A compression limiter retaining mechanism is installed on the periphery of the hole including the fixing through hole in the chain guide body to store and maintain the compression limiter. Basically, since the compression limiter is interposed between the chain guide body and the attachment bolt, the difference in thermal shrinkage occurring between the attachment bolt and the chain guide body is mitigated, thereby ensuring stable operation of the timing chain and improving durability. Furthermore, the compression limiter retaining mechanism prevents the compression limiter from detaching from the chain guide body during transport, and simultaneously prevents the compression limiter from detaching from the chain guide body during attachment to the member. Thus, the chain can be easily attached to the member, and workability during attachment can be improved. As long as it provides a guide, the specific composition can be anything.

[0027] [Example 1]

[0028] A chain guide according to the first embodiment of the present invention is used in combination with a timing system installed in an engine room, and is fixed to the engine room as a member to be attached and slides guides a chain running between sprockets. The chain guide (100) has a guide shoe that slides guides the running chain along the guide length direction, a chain guide body (110) that is detachably attached to the guide shoe and supports the guide shoe, and a compression limiter (150) that has a mounting hole (151) into which a mounting bolt is inserted to attach the chain guide (100) to a member to be attached, which is installed by being inserted into a fixing through hole (111) formed to penetrate in the width direction (guide width direction) of the chain guide body (110).

[0029] The chain guide body (110) is made of synthetic resin. When the chain guide (100) is a fixed guide, the fixing through holes (111) in the chain guide body (110) are formed at three locations spaced apart in the guide length direction of the chain guide body (110), as shown in FIG. 1, and a compression limiter (150) is fitted and installed in each of them.

[0030] In the hole rim part (120) including the fixing through hole (111) of the chain guide body (110), a tapered portion (121) is formed on the inner surface of the fixing through hole (111), as shown in FIGS. 2 to 4, in which the diameter decreases as it moves in one direction along the axial direction of the fixing through hole (111) (from right to left in FIG. 4).

[0031] Additionally, at the periphery of the hole (120), an annular groove (122) is formed that follows the outer rim shape (annular shape) of one end of the fixing through hole (111) and is separated from the outer rim of the fixing through hole (111) by a small gap and extends in the width direction from one side of the chain guide body (110) (left side of FIG. 4). Then, between this annular groove (122) and the inner circumferential surface of the fixing through hole (111), a lip (123) is formed by the inner ring circumferential wall of this annular groove (122) on the fixing through hole (111) side.

[0032] The thin section (123) is formed in the tapered portion (121), and as a result, the thin section (123) extends in a tilted state within the diameter direction of the fixing through hole (111) as it moves from the other side (right side of FIG. 4) toward the one side (left side of FIG. 4).

[0033] The length of the thin section (123), which is the inner ring circumferential wall of the annular portion (122) (left-right direction length in FIG. 4), is lower than the height of the chain guide body (110), which is the outer ring circumferential wall of the annular portion (122). As a result, when the retaining portion (154) of the compression limiter (150) described later is engaged in a state covering the inner edge area of ​​the tip portion of the thin section (123), the compression limiter (150) is prevented from protruding from the chain guide body (110).

[0034] The thickness of the thin section (123) is, for example, about 0.5 mm, and the length of the thin section (123) in the guide width direction is, for example, about 2.0 mm.

[0035] The circular groove (122) is composed of a plurality of circular arc groove-shaped grooves (125) divided through the bridge structure (124). The plurality of circular arc groove-shaped grooves (125) are installed at equal angles in the circular groove (122).

[0036] As shown in FIG. 5, an uneven structure (126) is formed on the inner surface of the through hole (111) for fixing the thin section (123), specifically on the inner surface of the thin section (123) of the tapered portion (121).

[0037] The compression limiter (150) is made of metal, such as an attachment bolt for attachment to the engine room, which is an attachment member, and is intended to prevent deformation caused by the difference in thermal shrinkage between the synthetic resin chain guide body (110) and the attachment bolt.

[0038] The compression limiter (150) has a cylindrical body (152) having an internal attachment hole (151), a flange portion (153) protruding outward in the radial direction from the base edge of the body (152), and a latching portion (154) protruding slightly inward in the radial direction from the front edge of the body (152). The attachment hole (151) functions as an attachment hole through which an attachment bolt, which serves as an attachment shaft for attaching the chain guide (100) to the engine room, which is the attachment member, is inserted.

[0039] The locking portion (154) of the compression limiter (150) is configured to be hooked onto one side of the hole periphery portion (120) of the chain guide body (110), specifically by covering the inner edge portion of the leading edge of the thin section (123) of the hole periphery portion (120) so as to be hooked onto the thin section (123). That is, the compression limiter (150) is formed so that a fixing through hole (111) can be inserted into the flange portion (153) and the locking portion (154).

[0040] The protrusion length of the latching portion (154) in the compression limiter (150) is approximately 0.1 mm.

[0041] In addition, in the chain guide (100) of this embodiment, a compression limiter holding mechanism for holding a compression limiter (150) is installed in the hole periphery (120) which includes a fixing through hole (111) in the chain guide body (110). The compression limiter holding mechanism is composed of at least one of the tapered shape portion (121), thin section (123), and uneven structure (126) of the hole periphery (120), and the holding portion (154) of the compression limiter. Although the chain guide (100) according to this embodiment is described as having all of these, the compression limiter holding function can be performed by having at least one of the above. For example, as shown in FIG. 6, a configuration in which only the tapered shape portion (121) and the uneven structure (126) are formed and the annular recess (122) (thin section (123)) is not formed is also acceptable.

[0042] The compression limiter (150) can be assembled by pressing it into the fixing through hole (111) of the chain guide body (110) from the other side of the chain guide body (110) toward the one side, with the leading end of the compression limiter (150) (the side of the locking part (154)) being at the front, and the center axis of the fixing through hole (111) and the center axis of the tubular body (152) being approximately aligned.

[0043] When the compression limiter (150) is installed by inserting it into the fixed through hole (111), the compression limiter (150) is stored and maintained within the fixed through hole (111) by the compression limiter holding mechanism. Specifically, the tubular body (152) of the compression limiter (150) is maintained by friction caused by the elasticity and uneven structure (124) of the tapered portion (121) of the fixing through hole (111) and the thin section (123), and furthermore, when the flange portion (153) contacts the other side of the chain guide body (110), the retaining portion (154) of the compression limiter (150) protrudes toward one side of the fixing through hole (111) and covers the inner edge area of ​​the leading edge of the thin section (123) of the hole periphery portion (120), thereby being engaged with the thin section (123), the movement of the compression limiter (150) is restricted and the compression limiter (150) is prevented from falling off the chain guide body (110). In addition, by securing the chain guide (100) to the engine room, the chain guide (100) can be easily secured to the engine room without cumbersome work, and workability is improved due to the attachment of the chain guide (100).

[0044] The chain guide (100) is assembled by inserting a compression limiter (150) into each fixing through hole (111), inserting an attachment bolt (not shown) into each attachment hole (151) of the compression limiter (150), and screwing it into a screw hole (not shown) in the engine room. As a result, the cylindrical body (152) of the compression limiter (150) is attached within the fixing through hole (111) formed in the chain guide body (110), with the inner surface of the fixing through hole (111) and the attachment bolt interposed therebetween.

[0045] In the attachment of the chain guide (100) to the engine room, the flange portion (153) of the compression limiter (150) may be positioned on the side facing the engine room and may function as a part that contacts the engine room when the chain guide (100) is attached to the engine room, or the clamping portion (154) of the compression limiter (150) may be positioned on the side facing the engine room.

[0046] In the above description, regarding the chain guide (100) of FIG. 1, a circular through hole with a cross-section perpendicular to the axial direction located in the center among the three fixing through holes (111) is described, but the present invention is also applicable to two fixing through holes (211) with an obround cross-section perpendicular to the axial direction shown in FIG. 7. In FIG. 7, in the hole periphery (220) including the fixing through hole (211), the hole periphery (120) is formed with an annular recess (222) that follows the outer shape (annular shape) of the fixing through hole (211) and is separated from the outer edge of the fixing through hole (211) by a small gap and extends in the width direction from one side of the chain guide body (110) (front side of FIG. 7), and between this annular recess (222) and the inner circumference of the fixing through hole (211), a thin section (223) is formed by the inner ring circumference wall on the fixing through hole (211) side of this annular recess (222).

[0047] In the chain guide (100) of this embodiment, the fixing through hole (211), which has an elliptical column shape with a cross-section perpendicular to the axial direction, is positioned at both ends in the guide length direction.

[0048] [Example 2]

[0049] As shown in FIG. 8, the chain guide (300) according to the second embodiment of the present invention has an annular recess (122) formed to be recessed in a state of being inserted from one side of the chain guide body (310) at the periphery of the hole (320), in addition to an annular recess (322) formed to be inserted from the other side of the chain guide body (310), and the other configuration is the same as the first embodiment described above. In FIG. 8, which illustrates the second embodiment, the same reference numerals are given to components having the same configuration as the chain guide (100) according to the first embodiment.

[0050] Specifically, the annular portion (322) is formed by being recessed in the width direction from the other side (right side of FIG. 8) of the chain guide body (110) by a small gap from the outer edge of the fixing through hole (311) and at the same time following the outer edge shape (annular shape) of the fixing through hole (311). And, between this annular portion (322) and the inner surface of the fixing through hole (311), a thin section (323) is formed by the inner ring circumference wall on the fixing through hole (311) side of this annular portion (322).

[0051] According to the chain guide (300) having annular portions (122, 322) formed on both sides, the thin sections (323, 323) formed on both sides of the fixing through hole (311) are formed to be easily bendable, thereby imparting elasticity to the fixing through hole (311). Consequently, the compression limiter (150) is securely held in place on the chain guide body (310) by the elasticity of the fixing through hole (311), and the detachment of the compression limiter (150) from the chain guide body (310) is reliably prevented, thereby further improving workability and transportability during attachment. Additionally, since the function of oil retention is exerted on both sides of the annular portions (122, 322), the oil retention around the fixing through hole (311) is further improved, the damping performance against vibration is improved, and the lubricity of the oil is improved, thereby reducing the risk of wear on the sliding part and extending the service life.

[0052] Although embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various design modifications are possible without departing from the present invention as described in the claims.

[0053] For example, in the above-described embodiment, the chain guide is configured as a fixed guide, but the compression limiter holding mechanism according to the present invention is also applicable to a oscillating guide that is axially supported to oscillate within the engine room shown in FIG. 9. The chain guide (400) configured as an oscillating guide has a chain guide body (410) and a compression limiter (150) installed by fitting it into a fixing through hole (411) formed at one end in the guide length direction of the chain guide body (410). The compression limiter (150) is formed with an attachment hole (151) that functions as a pivot hole for inserting an attachment bolt, etc., which serves as an oscillating axis while being attached to a member. And, the compression limiter holding mechanism is installed in the hole periphery (420) including the fixing through hole (411) and / or in the compression limiter (150) of the chain guide (400).

[0054] The axial length of the cylindrical body of the compression limiter (150) is equal to or slightly longer than the thickness in the width direction of the chain guide body (410), and with the attachment bolt fixed to the engine room, the chain guide (400) is configured to freely oscillate with the attachment bolt as the axis, with the axial movement between the head of the attachment bolt and the attachment surface of the engine room restricted.

[0055] The chain guide (400) is assembled by inserting the compression limiter (150) into the fixing through hole (411), inserting an attachment bolt (not shown) into the attachment hole (151) of the compression limiter (150), and attaching it by screwing it into a screw hole (not shown) in the engine room. As a result, the cylindrical body of the compression limiter (150) is oscillatingly attached to the engine room with the inner surface of the fixing through hole (411) formed in the chain guide body (410) and the attachment bolt interposed therebetween.

[0056] For example, in the chain guide of the above-described embodiment, although it was explained that the hole periphery is formed integrally with the chain guide body, it may be composed of separate parts. Specifically, the hole periphery may be an independent hole periphery member including a fixing through hole, and the chain guide body may be composed of a chain guide body frame having a receiving hole for accommodating the hole periphery member and the hole periphery member. According to a chain guide configured such that the hole periphery is formed separately from the chain guide body frame of the chain guide body, a compression limiter retaining mechanism can be added only to the hole periphery (hole periphery member), allowing for easy processing and manufacturing, thereby enabling the production of a chain guide with high productivity.

[0057] For example, in the above-described embodiment, the chain guide was explained as being installed within an engine having a timing system, but it is not limited to this and can be applied to various types of equipment.

[0058] For example, it is not limited to chain-based power transmission mechanisms but can be applied to similar power transmission mechanisms such as belts and ropes, and can be used in various industrial fields.

[0059] In addition, for example, the material of the chain guide body may be selected from a known suitable synthetic resin according to manufacturing conditions such as rigidity, durability, moldability, elasticity, and cost. Furthermore, the material of the guide shoe may also be selected from a known suitable material according to manufacturing conditions such as elasticity, friction resistance, rigidity, durability, moldability, and cost, and synthetic resin materials are particularly suitable. Explanation of the symbols

[0061] 100, 300, 500 ···Chain guide (fixed guide) 400, 600 ···Chain guide (oscillation guide) 110, 310, 410 ···Chain guide main body 111, 211, 311, 411 ···Fixing through holes 120, 220, 320, 420 ···hole main part 121 ···Tapered section 122, 222, 322 ···Fantasy Seductress 123, 223, 323 ···three-part segment 124 ···Bridge structure 125 ···Curved-home type waist 126 ···uneven structure 150 ···Compression limiter 151 ···Attachment work 152 ···Tubular body 153 ···Flange section 154 ···Gyejibu S1 ···Drive sprocket S2 ···Driven sprocket CH ···Timing chain P ···Attachment bolt (for oscillation) Q ···Attachment bolt (for fixing) T ···Chain tensioner E ···Engine room (attached component)

Claims

Claim 1 A chain guide comprising a guide shoe for sliding guide of a chain and a chain guide body supporting the guide shoe, wherein a compression limiter is fitted into a fixing through hole penetrating in the width direction of the chain guide body and has a mounting hole into which a mounting bolt for attaching the chain guide to a member is inserted, and a compression limiter retaining mechanism is installed in a hole periphery including the fixing through hole in the chain guide body or in the compression limiter to retain and maintain the compression limiter, and wherein the compression limiter retaining mechanism is composed of a thin section extending over the entire circumference and formed between the annular recess and the inner circumference of the fixing through hole, formed by forming an annular recess that is recessed in a state of being inserted in the width direction from one side of the chain guide body along the outer shape of one end of the fixing through hole in the hole periphery. Claim 2 A chain guide according to claim 1, characterized in that the compression limiter retaining mechanism is configured with a tapered shape in which the diameter is reduced as it faces one side in the axial direction formed on the inner circumference of the fixing through hole. Claim 3 A chain guide according to claim 1, characterized in that the annular portion is formed of a plurality of arc-groove shaped portions divided through a bridge structure. Claim 4 A chain guide according to claim 1, wherein the compression limiter is formed with a flange portion protruding radially outward from the base edge and a locking portion protruding radially outward from the tip edge and engaging with the periphery of the hole, and wherein the compression limiter retaining mechanism is composed of the locking portion of the compression limiter. Claim 5 A chain guide according to claim 1, characterized in that the compression limiter retaining mechanism is composed of an uneven structure formed on the inner circumference of a fixing through hole. Claim 6 A chain guide according to claim 1, characterized in that the hole periphery is formed integrally with the chain guide body. Claim 7 delete

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