WO2014192341A1 - Chain driving sprocket - Google Patents

Abstract

This chain driving sprocket (11) is provided with a rotation member (21) comprising multiple teeth (24a) capable of engaging with a chain (12) and provided along the outer periphery (28) at regular intervals along the circumferential direction, and with multiple buffer members (31) which are attached along the pitch circle (Q) of the teeth at an interval corresponding to the arrangement pitch (L) of the teeth such that inner plates (13) and outer plates (14) in the chain contact each other on at least one side in the teeth width direction of the teeth (24a) on the rotation member (21). When removing the buffer members (31) from the rotation member (21) for replacement, those of the buffer members that are identified, for example, as degraded and requiring replacement are replaced.

Description

Sprocket for chain drive

The present invention relates to a chain drive sprocket that drives a chain by rotating in a state in which the chain is engaged with a tooth portion provided on an outer peripheral portion.

Conventionally, in this type of chain drive sprocket, when the chain is driven, there is a problem that noise is generated when a roller or bush included in the chain falls on the tooth bottom of the sprocket tooth and collides. Therefore, in order to suppress the generation of such noise, a cushion ring (buffer member) is provided on both sides of the sprocket teeth in the tooth width direction, and the cushion ring receives the edge of the link plate of the chain. There has been proposed a chain sprocket with a cushion ring so as not to collide with the tooth bottom (for example, Patent Document 1).

JP 2006-38031 A

In the conventional sprocket described above, the cushion ring as a buffer member is formed in an annular shape over the entire circumferential direction of the sprocket. Therefore, if deterioration or damage is observed in a part of the circumferential direction of the cushion ring, the entire cushion ring can be integrated into one part even if no deterioration or damage is observed in other parts of the circumferential direction. There is a problem that it is necessary to replace the parts, and the cost associated with the replacement cannot be reduced.

The present invention has been made in view of such a situation, and an object of the present invention is related to a buffer member that reduces the mechanical impact on the chain and suppresses the generation of noise when the chain is driven. An object of the present invention is to provide a chain drive sprocket capable of reducing the cost associated with replacement.

In the following, means for solving the above problems and their effects are described.

A sprocket for driving a chain that solves the above problems includes a rotating member in which a plurality of teeth that can mesh with the chain are provided on the outer peripheral portion at equal intervals along the circumferential direction, and the tooth width of the tooth portion in the rotating member A plurality of cushioning members attached along the pitch circle of the tooth portion at intervals corresponding to the arrangement pitch of the tooth portion so as to be able to contact the link plate in the chain on at least one side in the direction; Prepare.

According to this configuration, since the buffer member is attached to the rotating member, when the chain is driven, the buffer member can relieve the mechanical impact on the chain and suppress the generation of noise. And when removing such a buffer member from the rotating member and replacing it, among the plurality of buffer members attached at intervals corresponding to the arrangement pitch of the tooth portions along the pitch circle of the tooth portions, for example, It is only necessary to replace the buffer member that is recognized to be deteriorated and needs to be replaced. Therefore, unlike the case where the buffer member is formed in an annular shape over the entire circumferential direction of the rotating member, the cost associated with replacement of the buffer member as a part can be reduced.

In the sprocket for driving the chain, it is preferable that the plurality of buffer members are attached along the pitch circle of the tooth portion at the same interval or twice as the arrangement pitch of the tooth portion.

If a plurality of buffer members are attached at intervals exceeding twice the arrangement pitch of the tooth portions, two or more link plates that cannot be received by the buffer member when the chain is driven are generated continuously. . For this reason, in such a case, a roller or the like located at a place where two or more continuous link plates are rotatably connected falls into the tooth bottom of the tooth portion and collides with the tooth bottom, generating noise. There is a possibility that. In this regard, according to the above-described configuration, two or more link plates that cannot be received by the buffer member are not continuously generated when the chain is driven. For this reason, the roller of the chain or the like does not collide with the tooth bottom of the tooth portion of the outer peripheral portion of the rotating member. Therefore, it is possible to satisfactorily suppress the generation of noise due to such a collision.

In the chain driving sprocket, the buffer member includes a mounting portion for the rotating member and a load receiving portion for receiving a load from the chain via the link plate, and the mounting portion has rigidity, The load receiving portion preferably has elasticity.

According to this configuration, since the attachment portion with respect to the rotating member has rigidity, the buffer member can be positioned with respect to the rotating member and attached in a stable state. On the other hand, since the load receiving portion has elasticity, the mechanical impact applied from the chain via the link plate can be relaxed, and the generation of noise can be suppressed.

In the chain drive sprocket, the load receiving portion includes a contact portion constituting a contact portion with the link plate, and an elastic portion interposed between the contact portion and the mounting portion, It is preferable that the material of the elastic portion has a Young's modulus smaller than that of the contact portion.

According to this configuration, durability can be ensured by selecting a material having a large Young's modulus for the contact portion that receives a load by contacting the link plate when the chain is driven. On the other hand, since the load applied to the attachment portion via the contact portion can be absorbed by the elastic portion made of a material having a small Young's modulus, it is possible to satisfactorily reduce the impact and suppress the generation of noise.

In the chain drive sprocket, the abutment portion is disposed away from the virtual plane toward a central region that is in contact with a virtual plane orthogonal to the radial direction of the rotating member and toward the axis of the rotating member. It is preferable to have an outer edge.

According to this configuration, when the chain is running, the outer edge of the contact portion does not contact the link plate of the chain, and the possibility that the contact portion is damaged due to sliding with the link plate of the chain can be reduced.

The present invention relates to a buffer member that can suppress the generation of noise by reducing the mechanical impact against the chain when the chain is driven and reducing the cost associated with the replacement of the buffer member. it can.

The perspective view which shows the chain drive state by the sprocket of 1st Embodiment. The perspective view of a rotation member. The perspective view of a buffer member. The disassembled perspective view of a buffer member. The front view which expands and shows the principal part of the chain drive state by a sprocket. The perspective view which shows the chain drive state by the sprocket of 2nd Embodiment. The perspective view which shows the chain drive state by the sprocket of 3rd Embodiment. The perspective view of the buffer member of the 1st modification. The perspective view of the buffer member of the 2nd modification.

(First embodiment)
Hereinafter, a first embodiment of a chain driving sprocket will be described with reference to the drawings.

As shown in FIG. 1, the sprocket 11 for driving a chain in this embodiment moves the chain 12 in the forward or reverse direction by rotating in a state where the chain 12 is engaged.

The chain 12 has a plurality of pairs of link plates opposed in the width direction. The plurality of pairs of link plates have a plurality of pairs of inner plates 13 and a plurality of pairs of outer plates 14. The pair of inner plates 13 are held in a state of being opposed to each other by being connected by a cylindrical bush (not shown). Outside each pair of inner plates 13, a pair of outer plates 14 are arranged alternately and in series with each pair of inner plates 13, and the ends adjacent to each other along the arrangement direction are within the bushing. The chain 12 is formed in a predetermined length by being rotatably connected by the inserted pin 15.

A roller 16 is rotatably mounted on the outer periphery of the pin 15 between the opposed inner plate 13 and outer plate 14. The roller 16 meshes with a tooth portion provided on the outer peripheral portion of the sprocket 11 and is pulled in the rotation direction of the sprocket 11, whereby the chain 12 moves in the forward direction or the reverse direction depending on the rotation direction of the sprocket 11. To do. At that time, the chain 12 makes the edges along the longitudinal direction of the inner plate 13 and the outer plate 14 contact the plurality of buffer members 31 provided at equal intervals along the circumferential direction on the outer peripheral portion of the sprocket 11. .

As shown in FIG. 2, the sprocket 11 includes a substantially disk-shaped rotating member 21 made of a metal material (for example, iron), a plurality of bolts 22 and a plurality of nuts made of a rigid metal material (for example, iron). 23, and a plurality of tooth bodies 24 made of a metal material (for example, iron) fixed to the rotating member 21. A shaft hole 25 into which a driving shaft (not shown) for transmitting a driving force to the rotating member 21 is fitted is formed at the center of the rotating member 21. The rotating member 21 rotates around the central axis P of the shaft hole 25 as the drive shaft rotates.

The rotating member 21 has an inner peripheral portion 26 formed so as to penetrate the shaft hole 25 and a radially outer side of the inner peripheral portion 26 that is thinner in the axial direction than the inner peripheral portion 26. An intermediate portion 27 that is continuous with the portion 26, and an outer peripheral portion 28 that is formed on the outer side in the radial direction of the intermediate portion 27 so as to be thinner in the axial direction than the intermediate portion 27 and are continuous with the intermediate portion 27. The outer peripheral portion 28 is formed in the entire circumferential direction through a step (not shown) on the outer peripheral side of the intermediate portion 27 so that the thickness in the axial direction is about half of the thickness of the intermediate portion 27 in the axial direction. An annular plate part. The same number of holes (not shown) through which the plurality of bolts 22 (20 in the present embodiment) can be inserted along the circumferential direction are formed at equal intervals (equal angular intervals) on the outer peripheral portion 28. . Further, in the outer peripheral portion 28 of the rotating member 21, a plurality of holes 29 (20 in this embodiment) through which bolts having a smaller diameter than the bolts 22 can be inserted inside the holes through which the bolts 22 can be inserted. They are formed at equal intervals (equal angular intervals). The holes for the bolts 22 and the holes 29 are arranged at the same angular position with respect to the shaft hole 25 of the rotating member 21.

In addition, the plurality of tooth bodies 24 are configured with ten tooth bodies 24 in the present embodiment. Each tooth body 24 is composed of a plate piece that is substantially the same in thickness in the axial direction as the outer peripheral portion 28 of the rotating member 21 and is formed in an arc shape along the contour of the outer peripheral portion 28. Two tooth portions 24 a that can mesh with the roller 16 of the chain 12 are formed on the outer peripheral edge of each tooth body 24. Each tooth body 24 has an outer peripheral part and an inner peripheral part (not shown), and a step (shown) is formed so that the thickness of the inner peripheral part is about half of the thickness of the outer peripheral part. Abbreviated). Each tooth body 24 is fixed to the rotating member 21 using bolts 22 or the like in a state where the inner peripheral side portion is superposed on the outer peripheral portion 28 of the rotating member 21 along the axial direction.

As shown in FIG. 1, a plurality (40 in this embodiment) of buffer members 31 are fixed to the outer peripheral portion 28 of the rotating member 21 at equal intervals (equal angular intervals) along the circumferential direction. Each buffer member 31 is rotated using a bolt 22 and a nut 23 for fixing each tooth body 24 to the rotating member 21 and a bolt 32 and a nut 33 inserted into each hole 29 of the outer peripheral portion 28 of the rotating member 21. It is fixed to the outer peripheral portion 28 of the member 21.

As shown in FIGS. 3 and 4, each buffer member 31 includes an attachment portion 34 that is attached in contact with the outer peripheral portion 28 of the rotating member 21 in the axial direction, and each pair of inner plate 13 and each of the pair of inner plates 13 when the chain 12 is driven. A load receiving portion 35 that receives a load from the chain 12 via the pair of outer plates 14 is provided. Each attachment part 34 consists of a bracket formed in a substantially L shape with a rigid metal material (for example, iron). Each mounting portion 34 includes a fixed piece portion 38 that can contact the outer peripheral portion 28 of the rotating member 21 in the axial direction, and a support piece portion 39 that is bent and extends from the fixed piece portion 38. A load receiving portion 35 is supported on the top.

Each load receiving portion 35 includes a contact portion 36 that constitutes a contact portion with each pair of inner plate 13 and each pair of outer plate 14 when the chain 12 is driven, and a support piece for the contact portion 36 and the mounting portion 34. And an elastic portion 37 interposed between the portions 39. Each contact portion 36 is made of a plate member formed of a metal material having rigidity (for example, iron) so that the surface forms a uniform plane, similarly to each attachment portion 34. On the other hand, each elastic part 37 is made of a plate member formed to have the same shape as the contact part 36 with a metal material (for example, aluminum) having a Young's modulus smaller than that of each contact part 36. Therefore, by providing each elastic part 37, each load receiving part 35 has elasticity.

As shown in FIG. 4, a hole 40 that penetrates each support piece 39 in the thickness direction is formed in the support piece 39 of the mounting portion 34 in each buffer member 31. In addition, the elastic portion 37 of the load receiving portion 35 in each buffer member 31 has a position that coincides with the hole 40 of the support piece portion 39 in a state where the elastic portion 37 is superimposed on the support piece portion 39 of the attachment portion 34. A similar hole 41 penetrating the elastic portion 37 in the thickness direction is formed. The abutting portion 36 that overlaps the elastic portion 37 is placed in the thickness direction at a position that coincides with the hole 41 of the elastic portion 37 when the abutting portion 36 is superimposed on the elastic portion 37. A similar hole 42 penetrating through is formed.

The elastic portions 37 and the abutting portions 36 are overlapped on the support piece portions 39 of the attachment portions 34 so that the holes 40, 41, 42 coincide with each other, and the elastic portions 37 are attached to the support piece portions 39. Contact. In this state, a bolt 43 is inserted from the hole 42 of each contact portion 36 into the hole 40 of each support piece portion 39 through the hole 41 of each elastic portion 37, and a nut 44 is attached to the tip of the bolt 43. By fastening, in each buffer member 31, each load receiving portion 35 is integrated with each mounting portion 34.

As shown in FIG. 1 and FIG. 5, each buffer member 31 is in the tooth width direction of the tooth portion 24 a in each tooth body 24 fixed to the outer peripheral portion 28 of the rotating member 21 (direction orthogonal to the paper surface in FIG. 5). It is fixed on both sides. That is, when the chain 12 is driven, the tooth portions 24a of the tooth portions 24a are arranged along the pitch circles Q of the tooth portions 24a so that the contact portions 36 come into contact with the inner plates 13 and the outer plates 14 of the pairs. Each buffer member 31 is fixed to the outer peripheral portion 28 of the rotating member 21 with an interval corresponding to the arrangement pitch L (in this embodiment, the same interval as the arrangement pitch L).

Next, the operation of the chain drive sprocket 11 configured as described above will be described.

As shown in FIGS. 1 and 5, when the chain 12 wound around the outer periphery of the sprocket 11 is driven, the sprocket 11 causes the roller 16 of the chain 12 to mesh with the tooth portion 24a of the tooth body 24 on the outer peripheral side. It is rotated in the state. And when each roller 16 of the chain 12 meshes with the tooth part 24a of each tooth body 24, each roller 16 comes to the tooth bottom between the tooth part 24a of each tooth body 24 and the tooth part 24a from the outside in the radial direction. When it falls and collides with the tooth bottom, an impact force is applied to the rotating member 21 via each tooth body 24, and a large noise is generated. Therefore, it is desired to avoid a collision that generates such an impact force or a large noise.

In this regard, in the present embodiment, as shown in FIGS. 1 and 5, when the sprocket 11 rotates to drive the chain 12 in a state where the chain 12 is wound around the outer periphery, each roller 16 rotates to each tooth body 24. Each of the buffer members 31 comes into contact with the edges along the longitudinal direction of each pair of inner plates 13 and each pair of outer plates 14 of the chain 12 before colliding with the bottom of the teeth between the tooth portions 24a. Then, after that point, the rollers 16 are restricted from moving toward the tooth bottom between the tooth portions 24a, and when the chain 12 is driven, the rollers 16 move the tooth bottom between the tooth portions 24a of the tooth bodies 24. Colliding with is avoided.

Further, since each buffer member 31 is also a portion where the inner plate 13 and the outer plate 14 are slidably contacted when the chain 12 is driven, it may be necessary to be deteriorated and replaced by aging. Therefore, in such a case, when each buffer member 31 is removed from the rotating member 21 and replaced, it is actually deteriorated among the plurality of buffer members 31 arranged in a distributed manner along the circumferential direction of the rotating member 21. Only one or several buffer members 31 that are recognized and need to be replaced are replaced.

When attaching the buffer member 31 to at least one side in the tooth width direction of each tooth portion 24a on the outer periphery of the rotating member 21, the height of the corresponding tooth portion 24a and the insertion of the bolts 22 and 32 for attaching the buffer member 31 are inserted. When there is an error in processing accuracy such as the position of the hole, the following fine adjustment work is performed. That is, even when there is such an error, the buffer member 31 that can contact the inner plate 13 and the outer plate 14 of the chain 12 at an optimum height is prepared with different height dimensions of the load receiving portion 35. The buffer member 31 selected from the plurality of types of buffer members 31 is attached to the rotating member 21.

Further, each buffer member 31 is attached at equal intervals along the pitch circle Q of each tooth portion 24a with the same interval as the arrangement pitch L of each tooth portion 24a. Therefore, two or more link plates (inner plate 13 and outer plate 14) that are not received by the buffer member 31 when the chain 12 is driven do not continuously occur in the connecting direction of the chain 12. Therefore, the roller 16 mounted on the outer periphery of the pin 15 that rotatably connects the ends of the inner plate 13 and the outer plate 14 that are adjacent to each other in the connecting direction has the inner plate 13 and the outer plate 14 that are adjacent to each other. It is received by contacting the buffer member 31 and is restricted from moving toward the shaft hole 25. Therefore, after such contact, the roller 16 is restricted from moving toward the tooth bottom of the tooth portion 24a.

Moreover, when each buffer member 31 is attached to the rotating member 21, it is positioned and attached in a stable state via the attachment portion 34 having rigidity. On the other hand, since the load receiving portion 35 of each buffer member 31 has elasticity, when the load receiving portion 35 receives the inner plate 13 and the outer plate 14 of the chain 12, the load receiving portion 35 is elastic. By deforming, the mechanical impact applied from the chain 12 via the inner plate 13 and the outer plate 14 is reduced.

In the load receiving portion 35 of each buffer member 31, the contact portion 36 that constitutes a contact portion of the chain 12 with the inner plate 13 and the outer plate 14 can be formed of a metal material having a higher Young's modulus than the elastic portion 37. It is. Therefore, durability can be ensured by selecting such a material having a large Young's modulus. On the other hand, as for the elastic portion 37, an optimal material is selected from a wide variety of materials having a Young's modulus smaller than that of the contact portion 36 according to the use environment.

According to the first embodiment, the following effects can be obtained.

(1) Since each buffer member 31 is attached to the rotating member 21, when the chain 12 is driven, each buffer member 31 comes into contact with the chain 12 in a state where the mechanical shock is reduced, thereby suppressing the generation of noise. can do. When such a buffer member 31 is removed from the rotating member 21 and replaced, a plurality of buffer members attached at intervals corresponding to the arrangement pitch L of the tooth portions 24a along the pitch circle Q of the tooth portions 24a. Of the 31 members, for example, only the buffer member 31 that has been recognized to be deteriorated and needs to be replaced may be replaced. Therefore, unlike the case where the buffer member 31 is a single part formed in an annular shape over the entire circumferential direction of the rotating member 21, the cost associated with replacement of the buffer member 31 as a part can be reduced.

(2) Since each buffer member 31 is given rigidity to the attachment portion 34 for the rotating member 21, it can be positioned relative to the rotating member 21 and attached in a stable state. On the other hand, since each load receiving portion 35 has elasticity, the mechanical impact applied from the chain 12 via the inner plate 13 and the outer plate 14 can be alleviated and the generation of noise can be suppressed.

(3) For each contact portion 36 that receives a load by contacting the inner plate 13 and the outer plate 14 when the chain 12 is driven, durability can be secured by selecting a material having a large Young's modulus. On the other hand, since the load applied to each mounting portion 34 via each contact portion 36 can be absorbed by each elastic portion 37 made of a material having a low Young's modulus, the impact can be satisfactorily reduced to suppress the generation of noise. can do.

(4) Even when there are variations in the processing accuracy of the plurality of tooth portions 24a provided on the outer peripheral portion 28 of the rotating member 21, the chain 12 has at least one side in the tooth width direction of the corresponding tooth portion 24a. A buffer member 31 that can contact the plates 13 and 14 at an optimum height can be selected from a plurality of types of buffer members 31 and attached to the rotating member 21. In this way, it is possible to finely adjust the mechanical shock mitigating function of the buffer member 31.

(Second Embodiment)
Next, the sprocket of 2nd Embodiment is demonstrated, referring a figure. In the sprocket of the second embodiment, the number of buffer members attached to the rotating member is different from that of the first embodiment. Since the other points are almost the same as those of the first embodiment, the same components are denoted by the same reference numerals, and redundant description is omitted.

Now, in the sprocket 11 of the first embodiment, in the outer peripheral portion 28 of the rotating member 21, the tooth portions are spaced along the pitch circle Q of the tooth portions 24a at intervals of every other tooth portion on both sides in the tooth width direction of the tooth portions 24a. A total of 40 buffer members 31 are attached at the same interval as the arrangement pitch L of 24a.

On the other hand, as shown in FIG. 6, in the sprocket 51 of the second embodiment, the interval between every two tooth portions, that is, the tooth portions, on both sides in the tooth width direction of the tooth portion 24a in the outer peripheral portion 28 of the rotating member 21. A total of 20 cushioning members 31 are attached along the pitch circle Q of 24a at intervals of twice the arrangement pitch L of the tooth portions 24a.

Therefore, although the outer peripheral portion 28 of the rotating member 21 is provided with 20 tooth portions 24a, the tooth portion 24a in which the buffer members 31 are attached on both sides in the tooth width direction and the buffer on both sides in the tooth width direction. Teeth 24a to which members 31 are not attached are alternately arranged. Therefore, one of the pair of inner plates 13 and the pair of outer plates 14 arranged in series in the chain 12 (the outer plate 14 in FIG. 6) is received by the buffer member 31 when the chain 12 is driven. However, the other plate (inner plate 13 in FIG. 6) is not received by the buffer member 31 when the chain 12 is driven.

Even in such a case, another link plate (in this case, the outer plate 14) adjacent to the link plate (in this case, the inner plate 13) that is not received by the buffer member 31 and that is rotatably connected by the pin 15. Is received by the buffer member 31. Therefore, the roller 16 mounted on the outer periphery of the pin 15 that rotatably couples the plates 13 and 14 falls toward the tooth bottom of the tooth portion 24a due to the presence of the link plate received by the buffer member 31. Is regulated.

According to the second embodiment, in addition to the effects (1) to (4) in the first embodiment, the following effects can be obtained.

(5) If the plurality of buffer members 31 are attached along the pitch circle Q of the tooth portion 24a with an interval exceeding twice the arrangement pitch L of the tooth portion 24a, when the chain 12 is driven Two or more link plates (the inner plate 13 and the outer plate 14) that cannot be received by the buffer member 31 are continuously generated along the traveling direction of the chain 12. Therefore, in such a case, there is a possibility that the roller 16 that rotatably connects two or more continuous link plates falls into the tooth bottom of the tooth portion 24a and collides with it to generate noise. In this regard, according to the present embodiment, when the chain 12 is driven, two or more link plates that are not received by the buffer member 31 do not continuously occur along the traveling direction of the chain 12. Therefore, the roller 16 of the chain 12 does not fall and collide with the tooth bottom of the tooth portion 24a of the outer peripheral portion 28 of the rotating member 21. Therefore, it is possible to satisfactorily suppress the generation of noise due to such a collision.

(6) Even when the number of the buffer members 31 attached to the outer peripheral portion 28 of the rotating member 21 is reduced, it is possible to restrict the roller 16 from colliding with the tooth bottom of the tooth portion 24a when the chain 12 is driven. The generation of noise can be suppressed while reducing the cost by the number of points.

Next, the sprocket of the third embodiment will be described with reference to the drawings. Note that the sprocket of the third embodiment is different from the first embodiment in the number of cushioning members and the number of teeth that are attached to the rotating member. Since the other points are almost the same as those of the first embodiment, the same components are denoted by the same reference numerals, and redundant description is omitted.

As shown in FIG. 7, in the sprocket 61 of the third embodiment, each tooth body 24 fixed to the outer periphery of the rotating member 21 by the bolt 22 has one tooth that can mesh with the roller 16 of the chain 12 on the outer periphery. A portion 24a is provided. The sprocket 11 of the first embodiment described above has two tooth portions 24a in the tooth body 24, whereas the sprocket 61 of the third embodiment has only one tooth portion 24a in the tooth body 24. . Therefore, when the chain 12 is driven, the tooth portions 24a of the tooth bodies 24 are engaged with every other roller 16 among the rollers 16 arranged at predetermined intervals along the traveling direction of the chain 12. The sprocket 51 rotates.

On the other hand, with respect to each buffer member 31, the arrangement pitch of the tooth portions 24a along the pitch circle Q of the tooth portions 24a on both sides in the tooth width direction of the tooth portions 24a on the outer peripheral portion 28 of the rotating member 21 (first embodiment). In total, 20 buffer members 31 are attached at equal intervals with an interval corresponding to twice the arrangement pitch L in this case.

Therefore, also in the third embodiment, a link plate (inner plate 13 in FIG. 7) that is not received by the buffer member 31 when the chain 12 is driven and a link plate (outer plate 14 in FIG. 7) that are received are generated. However, even in this case, another link plate (in this case, the outer plate 14) adjacent to the link plate (in this case, the inner plate 13) that is not received by the buffer member 31 and is rotatably connected by the pin 15 Is received by the buffer member 31. Therefore, the roller 16 mounted on the outer periphery of the pin 15 that rotatably couples the plates 13 and 14 falls toward the tooth bottom of the tooth portion 24a due to the presence of the link plate received by the buffer member 31. Is regulated.

According to the third embodiment, in addition to the effects (1) to (4) in the first embodiment and the effect (6) in the second embodiment, the following effects can be further obtained.

(7) Since each tooth body 24 of the sprocket 61 is provided with one tooth portion 24a, compared to the sprocket 11 to which each tooth body 24 having the two tooth portions 24a is attached, there are fewer tooth portions. The weight of can be reduced.

Note that the above embodiment may be modified as follows.

As shown in FIGS. 8 and 9, the surface of the contact portion 36 of the load receiving portion 35 in each buffer member does not need to be constituted by a single flat surface. That is, in the buffer member 71 of FIG. 8, the central region 72 of the buffer member 71 in the rotation direction of the rotary member 21 is formed so as to contact the virtual plane R orthogonal to the radial direction of the rotary member 21. On both sides of the central region 72, tapered regions 73 and 74 are formed which are inclined from the central region 72 to the outer end edges 36a and 36b of the contact portions 36 on both sides in the rotational direction. Therefore, the taper regions 73 and 74 are not arranged on the virtual plane R orthogonal to the radial direction of the rotating member 21, and the outer edges of the taper regions 73 and 74, that is, the contact portions 36. The outer end edges 36 a and 36 b are arranged away from the virtual plane R toward the axis P of the rotating member 21.

Further, in the buffer member 81 of FIG. 9, the entire surface of the contact portion 36 is formed in a convex curved shape along the rotation direction of the rotating member 21. The central region of the contact portion 36 is partially in contact with a virtual plane R that is orthogonal to the radial direction of the rotating member 21, but the outer edges 36 a and 36 b of the contact portion 36 are separated from the virtual plane R. The rotating member 21 is disposed away from the axis P.

In the buffer members 71 and 81 as described above, the link plate (the inner plate 13 and the outer plate 14) contacts the central region of the contact portion 36 on the virtual plane R when the chain 12 is traveling. On the other hand, the outer end edges 36a and 36b of the contact portion 36 do not contact the link plates (the inner plate 13 and the outer plate 14) of the chain 12. Therefore, the possibility that the contact portion 36 is damaged by sliding with the link plate can be reduced.

In each of the above embodiments, the material of the elastic portion 37 is not limited to aluminum but may be selected from various materials such as rubber and vibration-damping steel plate as long as the Young's modulus is smaller than that of the contact portion 36. It can be selected according to the usage environment.

In each of the above embodiments, the material of the mounting portion 34 in the buffer member 31 may be a metal material other than iron, such as stainless steel, as long as the material is rigid, and further, a rigid ceramic material, etc. It may be a material.

In each of the above embodiments, if the load receiving portion 35 of the buffer member 31 has elasticity, the load receiving portion 35 is replaced with an elastic portion 37 formed in a plate shape with a metal material having a small Young's modulus. A member (for example, a spring member) may be interposed between the contact portion 36 and the attachment portion 34.

-In each above-mentioned embodiment, buffer member 31 should just be attached to at least one side of the tooth width direction of tooth part 24a in rotation member 21, and is not necessarily attached to both sides of the tooth width direction of tooth part 24a. It does not have to be.

DESCRIPTION OF SYMBOLS 11,51,61 ... Sprocket, 12 ... Chain, 13 ... Inner plate, 14 ... Outer plate, 21 ... Rotating member, 24a ... Tooth part, 28 ... Outer peripheral part, 31, 71, 81 ... Buffer member, 34 ... Mounting part 35 ... load receiving part, 36 ... contact part, 37 ... elastic part, 73, 74, 82 ... surface, L ... arrangement pitch, P ... axis, Q ... pitch circle.

Claims (5)

A rotating member in which a plurality of teeth that can mesh with the chain are provided at equal intervals along the circumferential direction on the outer periphery;
On at least one side of the tooth part in the tooth width direction of the rotating member, an interval corresponding to the arrangement pitch of the tooth parts is arranged along the pitch circle of the tooth parts so as to be in contact with the link plate in the chain. A chain drive sprocket comprising a plurality of shock-absorbing members attached to the chain. 2. The chain drive sprocket according to claim 1, wherein the plurality of buffer members are attached at the same interval as the arrangement pitch of the tooth portions or at an interval twice the arrangement pitch. Each of the buffer members includes a mounting portion for the rotating member and a load receiving portion that receives a load from the chain via the link plate, and the mounting portion has rigidity, while the load receiving portion has elasticity. The chain drive sprocket according to claim 1, wherein the chain drive sprocket is provided. The load receiving portion includes a contact portion constituting a contact portion with the link plate, and an elastic portion interposed between the contact portion and the attachment portion, and the material of the elastic portion is the contact portion. The sprocket for driving a chain according to claim 3, wherein the Young's modulus is smaller than the material of the portion. The contact portion includes a central region that is in contact with a virtual plane orthogonal to the radial direction of the rotating member, and an outer edge that is spaced from the virtual plane toward the axis of the rotating member. The sprocket for driving a chain according to claim 4, wherein the sprocket is for driving a chain.

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