JPH0522898U - Gear damper - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] To suppress or prevent the generation of noise due to collision between stoppers 12 and 22 during resonance. [Structure] A gear 10 or a hub and another gear 20 are connected by a vibration-proof bush 30 so as to be relatively displaceable in the circumferential direction.
0 or the hub and the other gear 20, the gear damper in which the stoppers 12 and 22 that are opposed to each other in the circumferential direction via the appropriate free space S are provided in a protruding manner, the hole 14 is provided in one of the facing surfaces of the stoppers 12 and 22. A pressing piece 61 which is formed so as to be retractably housed in the hole 14 and contacts the other of the facing surfaces, and a pressing piece 61 which is deformably interposed between the bottom portion of the hole 14 and the pressing piece 61. Is provided with a cushioning member 60 including an elastomer piece 62 for urging the elastic piece 62 so as to always protrude from the hole 14.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improvement of a gear damper that suppresses the generation of gear rattle in a power transmission unit such as a transmission or a coupling.

[0002]

[Prior Art]

 Conventionally, as one type of gear damper, for example, as shown in FIGS. 5 and 6, a gear 110 meshed with one shaft 140 and a gear 120 meshed with the other shaft 150 are relatively displaceable in the circumferential direction by an anti-vibration bush 130. It is known that the anti-vibration bush 130 suppresses gear rattling noise. For the gears 110 and 120, the torque transmission function is not impaired even if the anti-vibration bush 130 is damaged by an excessive torque input, and the anti-vibration bush 130 is prevented from being damaged by an excessive torque input. In order to do so, stoppers 111 and 121 are formed facing each other in the circumferential direction with an appropriate floating space S therebetween.

[0003]

[Problems to be solved by the device]

 However, since this type of gear damper usually obtains an excellent anti-vibration effect against the rattling noise by setting the spring constant of the anti-vibration bush 130 to a low value, the rotation system resonates when the engine is started. Then, the stoppers 111 and 121 swing relatively in the circumferential direction and repeatedly collide at a high speed, which causes a problem that a very loud metallic noise is generated. In addition, it is considered effective to attach a buffer rubber to the stopper 111 or 121 to prevent such a problem, but it is necessary to attach a large buffer rubber to withstand a large load, which is suitable for practical use. I couldn't say that.

The present invention has been made in view of the above problems, and an object thereof is to provide a cushioning structure capable of withstanding a large load and to generate a large metallic sound due to collision of stoppers at resonance. Is to prevent.

[0005]

[Means for Solving the Problems]

 In order to solve the above problems, the present invention connects a gear or a hub and another gear concentrically combined with the gear or the hub with a vibration-proof bush so as to be relatively displaceable in the circumferential direction. In a gear damper in which stoppers projecting from each other and the other gears in the circumferential direction through an appropriate free space are projected, a hole is formed in one of the facing surfaces of the stopper so that it can be retracted and retracted in this hole. A pressing piece that is in contact with the other of the facing surfaces, and an elastomer piece that is interposed between the bottom portion of the hole and the pressing piece and urges the pressing piece in a direction to always project from the hole. The configuration has a cushioning member. Further, in this case, a slight compression margin remains in the elastomer piece when the free space becomes maximum in the circumferential direction, and the inner peripheral surface of the hole expands the elastomer piece in the process of the pressure piece being immersed in the hole. It is preferable to limit the amount of radial deformation.

[0006]

[Action]

 In the above configuration, when the stopper on the gear or hub side and the stopper on the other gear side are displaced relative to each other, the pressing piece compresses the elastomer piece in the hole while the opposing surfaces of both stoppers are in the process of approaching each other. Since the compression reaction force and viscoelasticity of the elastomer piece at the time of immersing suddenly decrease the approaching speed of the facing surfaces to each other, the contact between the stoppers is prevented or alleviated. At this time, the outer peripheral surface of the elastomer piece, which expands and deforms due to compression in close contact with the inner peripheral surface of the hole in the process until the pressing piece is completely immersed in the hole, restricts the expandable deformation of this elastomer piece. Since it is not deformed by further compression, it can withstand a large load. Even if the free space is maximized in the circumferential direction due to the relative displacement of the stopper, the pressing piece is in constant contact with the opposing surface of the mating stopper due to the slight compression margin of the elastomer piece, so the collision movement of the pressing piece itself. Does not occur.

[0007]

【Example】

 1 and 2 show an embodiment of a gear damper of the present invention, in which 10 is a gear in which an inner diameter tooth 11 meshes with an outer peripheral tooth 41 of one shaft 40, and 20 is an inner diameter tooth 21 of the other. A second gear (another gear) that meshes with teeth 51 on the outer periphery of the shaft 50, and both gears 10 and 20 are combined concentrically with each other and are relatively displaceable in the circumferential direction. The gears 10 and 20 are provided with stoppers 12 and 22 which are opposed to each other in the circumferential direction with an appropriate floating space S, and are formed in a circumferentially equally-arranged manner. Further, 30 is a vibration-proof bush that elastically connects both gears 10 and 20, and a sleeve 31 fitted to the outer peripheral surface of the boss portion 13 of the gear 10 and an outer diameter tubular shape of the second gear 20. It comprises a sleeve 32 fitted to the inner peripheral surface of the portion 23, and an elastomer bush body 33 vulcanized and bonded between the sleeves 31 and 32.

Holes 14 are formed in one of the facing surfaces of the stoppers 12, 22 facing each other on both sides of the floating space S, that is, on both side surfaces of the stopper 12 on the gear 10 side in the illustrated embodiment. A cushioning member 60 is attached to each hole 14. As shown in the enlarged view of FIG. 3, the cushioning member 60 includes a pressing piece 61 which is housed in the hole 14 and slidably accommodated therein and which is made of resin or a material having a large rigidity, and between the bottom of the hole 14 and the pressing piece 61. And a columnar elastomer piece 62 that urges the pressing piece 61 so that the pressing piece 61 always protrudes from the hole 14 by being deformable. The elastomer piece 62 is integrated with the pressing piece 61 by fitting or adhering a part 62a thereof to the back surface 61a of the pressing piece 61.

In the elastomer piece 62, even if the floating space S is maximized in the circumferential direction, a slight compression margin between the bottom of the hole 14 and the pressing piece 61 remains, so that the pressing piece 61 is The tip surface 61a formed in a smooth spherical shape is constantly in contact with one side surface of the stopper 22 on the second gear 20 side due to the elasticity of the elastomer piece 62.

Between the outer peripheral surface of the elastomer piece 62 and the inner peripheral surface of the hole 14 accommodating the elastomer piece 62, the diameter expansion deformation of the elastomer piece 62 due to compression by the pressing piece 61 is within a predetermined range. There is an allowable gap δ. The gap δ is set to a size such that it is filled with the elastomer piece 62 whose diameter is expanded and deformed when the pressing piece 61 is almost completely immersed in the hole 14 or immediately before that.

In the gear damper of the present embodiment having the above-described configuration, the stopper 12 on the gear 10 side and the stopper 22 on the second gear 20 side are repeatedly repeated in the circumferential direction due to resonance at the time of starting the engine. When displaced, the pressing pieces 61 of the cushioning member 60 are pushed by the stopper 22 and set into the hole 14 in the portion where the opposing surfaces of the stoppers 12 and 22 are approaching each other, that is, the floating space S is in the process of shrinking. On the contrary, in the portion where the floating space S is in the process of expanding, the pressing piece 61 follows the stopper 22 and projects from the hole 14 due to the elongation of the elastomer piece 62. Therefore, the vibration energy is damped by the damping force due to the viscoelasticity of the elastomer piece 62 during the deformation process and the damping force generated by the sliding of the pressing piece 61 and the hole 14.

Further, in the process in which the pressing piece 61 is immersed in the hole 14, the outer peripheral surface of the elastomer piece 62, which expands and deforms due to the compression, comes into contact with the inner peripheral surface of the hole 14, so that the deformation speed is increased. Since it is suppressed, the compression reaction force of the elastomer piece 62 is rapidly increased, and the approach speed between the facing surfaces of the stoppers 12 and 22 is rapidly decreased. Then, at the time when the pressing piece 61 is completely immersed in the hole 14 or immediately before that, when the gap δ in the hole 14 is filled with the expanded diameter elastomer piece 62, the elastomer piece 62 is further deformed. do not do. Therefore, the approaching of the facing surfaces is restricted, the collision is moderated or prevented, and the elastomer piece 62 can withstand a large load.

Further, as described above, the outer peripheral surface of the elastomer piece 62 comes into contact with the inner peripheral surface of the hole 14 to restrict the deformation, thereby controlling the relative movement of the stoppers 12, 22 at the time of resonance. Since the elastomer piece 62 is usually soft, the spring constant of the gear damper can be usually kept low, and the effect of absorbing the rattling noise of the gears 10 and 20 can be enhanced.

In the process of increasing or decreasing the gap δ in the hole 14 due to the diameter expansion / contraction deformation associated with the expansion and contraction of the elastomer piece 62, the air in the gap δ is easily escaped and returned so that the hole It is desirable to provide ventilation holes at 14. When the elastomer piece 62 is in the compression process in the hole 14 on one side of the stopper 12, the elastomer piece 62 is in the expansion process in the hole 14 on the other side of the stopper 12, so that the vent hole is If the holes 14 on both sides of 12 are provided so as to communicate with each other, the diameter δ is reduced from the side where the gap δ is reduced by the diameter expansion deformation due to the compression of the elastomer piece 62, and the diameter reduction deformation is caused due to the expansion of the elastomer 62. The air circulates smoothly toward the side where the gap δ is enlarged.

FIG. 4 shows the present invention applied to a gear damper of a type different from the above. That is, the outer gear teeth 21 ′ of the second gear 20 ′, which is connected to the gear 10 via the anti-vibration bush 30 so as to be relatively displaceable in the circumferential direction, engages with the gear teeth 10 of the inner diameter of the gear 10. It has a structure in which it meshes with an external gear 80 axially attached to a shaft 70 parallel to the above, and the other structure is the same as that of the previous embodiment.

The present invention is not limited to the illustrated embodiment. For example, the hole 14 and the cushioning member 60 attached thereto may be provided on the stopper 22 side, and instead of the gear 10 in FIG. 4, various types such as a hub having a shaft 40 attached thereto may be used. The present invention can be applied to the type of gear damper.

[0017]

[Effect of the device]

 The gear damper of the present invention decelerates the relative displacement speed between the stoppers by the retracting operation of the pressing piece of the cushioning material that follows the relative displacement of the stoppers in the circumferential direction and the accompanying deformation operation of the elastomer piece. , The outer peripheral surface of the elastomer piece that expands and deforms with compression is brought into close contact with the inner peripheral surface of the hole to restrict the deformation, which damps the collision motion of the stoppers, so that the buffer member does not resonate at the time of resonance. It is possible to prevent the generation of a large metallic noise due to repeated collisions of the stoppers, and it is possible to withstand a large load. Moreover, since the spring constant is usually low, it is possible to improve the function of reducing gear rattle noise. Produce the effect.

[Brief description of drawings]

FIG. 1 is a half sectional view taken along a plane orthogonal to an axis showing an embodiment of a gear damper of the present invention.

FIG. 2 is a half sectional view similarly cut along a plane passing through the axis.

FIG. 3 is likewise an enlarged cross-sectional view of a main part.

FIG. 4 is a half cross-sectional view taken along the plane passing through the axis of the gear damper according to another embodiment of the present invention.

FIG. 5 is a half cross-sectional view taken along a plane orthogonal to an axis showing an example of a conventional structure.

FIG. 6 is a half sectional view similarly cut along a plane passing through the axis.

[Explanation of symbols]

 10 Gears 11, 21, 21 '41, 51 Teeth 12, 22 Stopper 13 Boss 14 Hole 20 Second Gear (Other Gear) 23 Outer Diameter Cylindrical Section 30 Vibration Isolation Bushing 31, 32 Sleeve 33 Bushing Body 40, 50 , 70 Shaft 60 Cushioning member 61 Pressing piece 62 Elastomer piece 80 External gear S Floating space δ Gap

Claims (2)

[Scope of utility model registration request] 1. A gear 10 or hub, and another gear 20 concentrically combined with the gear 10 or hub,
A gear damper, which is connected to a gear 10 or a hub and another gear 20 so as to be relatively displaceable in the circumferential direction by means of an anti-vibration bush 30, and has stoppers 12 and 22 that are circumferentially opposed to each other through an appropriate floating space S, is provided. A hole 14 is formed in one of the facing surfaces of the stoppers 12 and 22, and the pressing piece 61 is housed in the hole 14 so as to be retractable and comes into contact with the other of the facing surfaces, and the bottom portion of the hole 14 is pressed. A gear damper comprising a cushioning member 60 including an elastomer piece 62 that is deformably interposed between the pieces 61 and biases the pressing piece 61 in a direction to always project from the hole 14. 2. The elastomer piece 62 according to claim 1, wherein a slight compression margin remains when the free space S reaches the maximum in the circumferential direction, and the inner peripheral surface of the hole 14 extends into the hole 14. A gear damper characterized in that the amount of radial expansion deformation of the elastomer piece 62 is regulated in the process of immersing the pressing piece 61.