JPH074945U - Torsional damper - Google Patents

Abstract

(57) [Abstract] [Purpose] In a mating type torsional damper, slipping does not occur on the mating surfaces of the hub 10, the elastomer member 30, and the inertial mass body 20 even when a large vibration torque is input, which is excellent. Get the vibration control function. A second elastomer member bonded to one of the radial surface 13a of the hub 10 and one end surface 22 of the inertial mass body 20 axially opposed to the radial surface 13a and slidably contacted to the other. 40, and the frictional force of the second elastomeric member 40 suppresses the swinging of the inertial mass body 20 in the circumferential direction, whereby the hub 10 and the elastomeric member 3 are provided.
The fitting surface with 0 and the elastomer member 30 and the inertial mass body 2
Prevents slippage of the mating surface with 0.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improvement of a torsional damper that absorbs vibration of a rotary drive system such as an engine crankshaft.

[0002]

[Prior art]

 This type of torsional damper basically consists of a hub fixed to the axial end of the engine crankshaft and an annular inertial mass body arranged close to the hub, which is elastically coupled via an elastomer member. The resonance system consisting of the inertial mass body and the elastomer member resonates so as to cancel the vibration of the crankshaft. Mainly against torsional vibration of the crankshaft (vibration in the rotational direction). It has a remarkable damping function.

There is a torsional damper called a fitting type, and a typical conventional example thereof is disclosed in, for example, Japanese Utility Model Laid-Open No. 63-170630. In other words, this mating type torsion damper has an advantage that it can be manufactured at low cost, but it has a vibration input torque, because an elastomer member (elastic body) is press-fitted between the hub and the inertial mass body (vibration ring). If the size exceeds a certain level, slip may occur between the hub and the elastomer member, or between the inertial mass body that resonates in the circumferential direction and the elastomer member, and the elastomer member may wear and cause sufficient resonance. There is a problem that the damper function cannot be exerted.

To prevent the occurrence of such slip, it is effective to bond an elastomer member, and such a technique is disclosed in, for example, Japanese Utility Model Publication No. 3-2032. That is, as shown in FIG. 4, this torsional damper includes an elastomer between a metal sleeve 1a mounted on the outer circumference of the hub 1 and an inertial mass body (vibration ring) 3 arranged on the outer circumference thereof. The member (rubber-like elastic body) 2 is integrally bonded (baked) simultaneously with molding. Further, a friction ring 4 made of a resin material or a refractory composite sintered body is provided between the radially expanded portion 1a having the outer diameter portion formed on the hub 1 and the end surface 3a of the inertial mass body 3 facing the radially expanded portion 1a. Since it is slidably sandwiched, the auxiliary damping function by the frictional force of the friction ring 4 is added to the resonance damper function of the inertial mass body 3 and the elastomer member 2.

[0005]

[Problems to be solved by the device]

 However, like the torsional damper shown in FIG. 4, the elastomer member 2 integrally vulcanized between the sleeve 1a and the cylindrical surface of the inertial mass body 3 which face each other in the radial direction is durable due to contraction after molding. There is a problem that residual stress in the pulling direction that hinders the property is generated, and the manufacturing cost is higher than that of the mating type torsion damper. Further, since the friction ring 4 for obtaining the auxiliary damping is made of the resin material or the refractory composite sintered body, when the inertial mass body 3 is shaken in the axial direction, the friction force of the friction ring 4 is increased. There is a risk that the auxiliary damping function due to will not be fully exerted.

The present invention has been made under the circumstances as described above, and its main purpose is to provide a fitting type torsional damper for a hub, an elastomer member, and an inertial mass body even when a large vibration torque is input. This is to obtain an excellent vibration control function without slippage on the mating surfaces.

[0007]

[Means for Solving the Problems]

 The above technical problems can be effectively solved by the present invention. That is, the torsional damper according to the present invention comprises a hub having a radial surface extending from one end of the outer peripheral surface to the outer diameter side, an inner peripheral surface facing the outer peripheral surface of the hub, and one end surface of the hub in the radial direction described above. An annular inertial mass body facing the surface, an elastomer member press-fitted between the outer peripheral surface of the hub and the inner peripheral surface of the inertial mass body, and the radial surface and one end surface of the inertial mass body. A second elastomer member that is adhered to one of the two and is slidably contacted to the other. In the present invention, it is more preferable that the radial surface, the one end surface of the inertial mass body, and the second elastomer member interposed therebetween have cross sections cut along a plane passing through the axial center, respectively. It has a corresponding curved shape.

[0008]

[Action]

 In the torsional damper having the above structure, the resonance system formed by the elastomer member on the outer circumference of the hub and the inertial mass body on the outer circumference resonates so as to cancel the vibration due to the vibration of the rotary drive system. The inertial mass body is repeatedly displaced in the circumferential direction with respect to the hub due to its circumferential resonance motion.However, the second elastomer member bonded to the radial surface of the hub or one end surface of the inertial mass body is The contact surface on the anti-bonding side produces a damping force by sliding on one end surface of the inertial volume or the radial surface of the hub, and suppresses excessive vibration of the inertial volume.

Since the contact surface on the anti-adhesion side of the second elastomer member elastically contacts the radial surface of the hub or one end surface of the inertial mass body, the inertial mass body has axial runout. The contact state is maintained well, and the damping force due to sliding is less likely to be impaired. Also, by making the radial surface of the hub, the one end surface of the inertial mass body, and the cross section of the second elastomer member have curved shapes that correspond to each other, the contact area increases, so the damping force due to friction is reduced. Is further enhanced.

[0010]

【Example】

 FIG. 1 shows a first embodiment of a torsional damper according to the present invention. In this figure, reference numeral 10 is a metal hub, and this hub 10 is fixed to an axial end of a crankshaft of an engine (not shown) in an inner peripheral hole 11, and a tubular portion 12 and an outer diameter side from one end thereof. The extended outer diameter expanding portion 13 is integrally provided. A pulley groove 14 is formed on the outer periphery of the outer diameter developing portion 13. Reference numeral 20 denotes a metallic annular inertial mass body arranged on the outer peripheral side of the cylindrical portion 12 of the hub 10. A pulley groove 21 is formed on the outer periphery thereof, and one end face 22 thereof has an outer diameter of the hub 10. It opposes the expanding portion 13 in the axial direction. Reference numeral 30 denotes a cylindrical elastomer member, which is press-fitted between the outer peripheral surface 12a of the cylindrical portion 12 of the hub 10 and the inner peripheral surface 23 of the inertial mass body 20 radially opposed to the outer peripheral surface 12a. Reference numeral 40 denotes a disk-shaped second elastomer member, which is adhered via an adhesive agent A to the radial surface 13a of the outer diameter developing portion 13 of the hub 10 which faces the inertial mass body 20 in the axial direction.

In the cross-sectional shape shown in the drawing taken along a plane passing through the axis O, the outer peripheral surface 12a of the tubular portion 12 of the hub 10 is formed in a curved shape in which the axial center portion is partially raised. The inner peripheral surface 23 of the inertial mass body 20 on the outer peripheral side thereof is formed in a curved shape in which the central portion in the axial direction is correspondingly recessed. Therefore, the cylindrical elastomer member 30 press-fitted between the opposing peripheral surfaces 12a and 23 is also curved, and the cylindrical portion 12 of the hub 10, the elastomer member 30, and the inertial mass body 20 are fitted together. It has a so-called convolution-shaped fitting structure that prevents axial displacement of the surfaces. The one end surface 22 of the inertial mass body 20 is pressed against the second elastomer member 40 by an appropriate force by the elasticity of the elastomer member 30 in the axial direction.

That is, this torsional damper has a fitting type structure in which the elastomer member 30 is press-fitted between the hub 10 and the opposed peripheral surfaces 12 a and 23 of the inertial mass body 20. This fitting type structure can be manufactured at a lower cost than the structure (bush type) in which the elastomer member 30 is vulcanized between the hub 10 and the opposed peripheral surfaces 12a and 23 of the inertial mass body 20. In addition, the elastomer member 30 has no residual stress in the tensile direction due to molding shrinkage, but rather is appropriately compressed, which is advantageous in strength.

The second elastomeric member 40 adhered to the radial surface 13 a of the hub 10 has a contact surface 41 on the opposite side of the adhered surface, one end surface of the inertial mass body 20 that resonates in the circumferential direction with rotation. By making sliding contact with 22, the inertial mass body 20 is prevented from excessive vibration in the circumferential direction. Further, the second elastomer member 40 has a high coefficient of friction of the elastomer material itself, and the inertial mass body 20 is pressed by the elastomer member 30 and is in elastic contact with the second elastomer member 40 at all times. Therefore, a significant damping force for the inertial mass body 20 is obtained. Therefore, despite the torsional damper having the fitting type structure, the fitting surface between the cylindrical portion 12 of the hub 10 and the elastomer member 30 or the inertial mass body 20 and the elastomer when the vibration input torque becomes large. The occurrence of slip on the fitting surface with the member 30 is effectively prevented.

FIG. 2 shows a second embodiment of the torsional damper according to the present invention. That is, this torsional damper is a plane that passes through the axis O, like the cylindrical portion 12 of the hub 10, the elastomer member 30, and the inertial mass body 20 having a convolution-shaped fitting structure. In the cross-section shown in the drawing cut by step 2, the radial center portion of the bonding surface (radial surface 13a) of the outer diameter expanding portion 13 of the hub 10 to the second elastomer member 40 is partially raised to the inertial mass body 20 side. Therefore, the second elastomer member 40 is also curved along the curved shape of the radial surface 13a, and the one end face 22 of the inertial mass body 20 is also formed into the second elastomer portion. Corresponding to the curved shape of the contact surface 41 of the material 40, it is formed in a partially recessed shape.

Therefore, according to this embodiment, since the inertial mass body 20 and the second elastomeric member 40 are in contact with each other at the curved surfaces extending in the circumferential direction, the contact area is increased. As a result, the effect of preventing slippage on the fitting surface between the tubular portion 12 of the hub 10 and the elastomer member 30 or the fitting surface between the inertial mass body 20 and the elastomer member 30 is further improved. Further, excessive eccentric movement of the inertial mass body 20 at the time of bending vibration input can be effectively suppressed.

FIG. 4 shows a third embodiment of the torsional damper according to the present invention. That is, this torsional damper is one in which the hub 10 is molded by pressing a metal plate, and the tubular portion 12 of the hub 10, the elastomer member 30, the fitting shape of the inertial mass body 20, and the inertial mass. The contact shape between the body 20 and the second elastomeric member 40 is basically the same as in the second embodiment described above.

The present invention is not limited to the illustrated embodiment. For example, although the second elastomer member 40 has been described as being bonded to the radial surface 13a of the hub 10 via the adhesive A, this is baked at the same time when the second elastomer member 40 is vulcanized and molded. It can also be adhered by doing so. The second elastomeric member 40 may be adhered to the one end surface 22 of the inertial mass body 20 and slidably contacted with the radial surface 13a of the hub 10. In this case, The mass of the elastomeric member 40 is included as a part of the inertial mass of the resonance system.

[0018]

[Effect of device]

 According to the torsional damper of the present invention, in addition to the frictional force of the second elastomer member, the elasticity of the second elastomer member maintains a good contact state with the inertial mass body or the hub. Since the frictional force is increased by adopting the curved shape, excessive shake of the inertial mass body in the circumferential direction can be suppressed. Therefore, despite the fitting type structure in which the elastomer member is press-fitted between the opposing peripheral surfaces of the hub and the inertial mass body, the fitting of the hub and the elastomer member when a large vibration torque is input. It is possible to effectively prevent slippage of the surface and the fitting surface between the elastomeric member and the inertial mass body, and therefore, it is possible to expand the usage conditions of the inexpensive fitting type torsional damper.

[Brief description of drawings]

FIG. 1 is a half sectional view showing a first embodiment of a torsional damper according to the present invention by cutting along a plane passing through an axis.

FIG. 2 is a half sectional view showing a second embodiment of a torsional damper according to the present invention by cutting along a plane passing through an axis.

FIG. 3 is a half cross-sectional view showing a third embodiment of the torsional damper according to the present invention by cutting along a plane passing through an axis.

FIG. 4 is a half-cut sectional view showing an example of a conventional torsional damper cut along a plane passing through an axis.

[Explanation of symbols]

 10 hub 11 inner peripheral hole 12 tubular part 12a outer peripheral surface 13 outer diameter developing part 13a radial surface 14,21 pulley groove 20 inertial mass body 22 one end surface 23 inner peripheral surface 30 elastomer member 40 second elastomer member 41 contact surface A adhesive

Claims (2)

[Scope of utility model registration request] 1. A hub (10) having a radial surface (13a) extending from one end of the outer peripheral surface (12a) to the outer diameter side, and an inner peripheral surface (23) being an outer peripheral surface () of the hub (10). 12a)
An annular inertial mass body (20) having one end surface (22) facing the radial surface (13a), and an outer peripheral surface (12a) of the hub (10) and the inertial mass body (20). An elastomer member (30) press-fitted between the peripheral surface (23) and one of the radial surface (13a) and one end surface (22) of the inertial mass body (20) and the other. Second elastomeric member (40) slidably contacted with the
And a torsional damper characterized by including. 2. The method according to claim 1, wherein the radial surface (13a), one end surface (22) of the inertial mass body (20), and the second elastomer member (40) interposed therebetween. A torsion damper characterized in that cross-sections cut along a plane passing through the axis have curved shapes corresponding to each other.