JPH01316521A - Torsional vibration damping device - Google Patents

Abstract

PURPOSE:To stabilize a vibration absorbing and damping capability providing an idler provided with a radial arm between hub arms so as to rotate relatively to a hub having a plurality of hub arms in a radial direction, interposing a coil spring between the hub arm and a radial arm and forming a curing layer on at least one outer surface of the hub or the idler. CONSTITUTION:A plurality of hub arms 29 are projected in a radial direction of a hub 20. An idler 62 provided with a radial arm 63 extended between the adjacent hub arms 29 is disposed so as to rotate relative to the hub 20. The hub 20 and the idler 62 are connected by means of coil springs 60, 61 so as to rotate relatively between the hub arm 29 and the radial arm 63. At that time, curing layers 29a, 63a are formed on at least one outer surface of the hub 20 or the idler 62. At the time of connecting a clutch, a rotating force is converged on the outer surface abutting against the coil springs 60, 61 and an abrasion resistance is improved due to the curing layers 29a, 63a and a power is stably transferred for a long period.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a torsional vibration damping device used in a power transmission system of an automobile or the like.

Conventional torsional vibration damping devices utilize the rotational force transmitted to the drive plate through the clutch facing when the clutch is connected through a spring member that connects the drive plate and the hub so that they can rotate relative to each other. The transmission is transmitted to the hub, and is configured to rotate an output shaft spline-fitted to the hub. In recent years, this type of torsional vibration damping device has been disclosed, for example, in Japanese Patent Application Laid-Open No. 184229/1983.
In order to more effectively absorb torsional vibrations caused by torque fluctuations during low-torque operations such as when the engine is idling, the hub is divided into an inner hub and an outer hub. The outer hub is fitted onto the outside so that it can rotate relative to each other by a predetermined angle, and the inner hub and the outer hub are connected by a low-rigidity spring member with a small spring constant, allowing the outer hub and the drive plate to rotate relative to each other. The invention has been improved so that a low-rigidity spring member acts before a high-rigidity spring member (coil spring) with a relatively large spring constant that is elastically connected to the coil spring acts. In addition, the outer hub has a structure that can rotate relative to the outer circumference of the outer hub to increase the relative rotation angle between the drive plate and the hub, and to exhibit excellent vibration absorption performance even when used for torque transmission over a wide range. A plurality of pairs of coil springs are disposed that act in series through a radial arm of a floater fitted onto the outside of the coil spring, and these plurality of coil spring groups are engaged with a drive plate to obtain a long deflection amplitude of the coil spring. It has been devised so that it can be used.

Problems to be Solved by the Invention However, in such conventional examples, when the drive plate rotates relative to the outer hub when the clutch is connected (i.e., when driving torque is transmitted), the coil spring moves against the idler. Since the radial arm is compressed between the radial arm and the hub arm of the outer hub, rotational force is concentrated on the radial arm and the coil spring of the hub arm that come into contact with the coil spring. Therefore, the hub and the roller are exposed to severe usage conditions, and there is a risk that the hub and the roller will suffer fatigue failure relatively early.

Means for Solving the Problems In the present invention, in order to solve the problems of the prior art described above, a hardened layer is formed on the outer surface of at least one of the hub or the roller.

As a result of the present invention having the above configuration, when the drive plate compresses the coil spring and rotates relative to the hub when the clutch is connected (during drive torque transmission), the outer part that comes into contact with the coil spring of the hub arm and the radial arm is rotated relative to the hub. Although the rotational force is concentrated on the surface, the hardened layer formed on the outer surface of the hub and the roller has improved mechanical strength and wear resistance, ensuring stable power transmission over a long period of time. will be held.

Embodiment What is shown in the sectional view in FIG. 1 and in the partially cutaway front view in FIG. 2 is a clutch disc l as a torsional vibration damping device according to an embodiment of the present invention. .

This clutch disc l generally includes a hub 20 and a pair of drive plates 30 that are provided so as to be able to elastically rotate relative to the hub 20 within a predetermined angle while substantially enveloping the outer circumferential side of the hub 20. .31, and friction plates 40.40 fixed to the outer periphery of these drive plates 30.31.

A more detailed explanation of each component is as follows.

The hub 20, as shown in partial detail in FIG.
Inner hub 2 splined to the output shaft (not shown)!
The inner hub 21 is fitted onto the inner hub 21 via a spring member (for example, a C-shaped spring) 23.
and an outer hub 22 coupled to the outer hub 22 so as to be elastically rotatable relative to each other within a predetermined angle. In addition, ]1
One end of the spring member 23 is engaged with the inner hub 21, and the other end is engaged with the outer hub 22. In such a coupled state, the outer hub 22 is attached to the inner hub 21 by the outer protrusions 21a formed thereon.
Elastic relative rotation is possible only between the angles limited by the and notches 22a, that is, the angles O in the forward direction (optional) and Ob (arbitrary) in the reverse direction.

Furthermore, sub-plates 24 and 25 are attached to both sides of the inner circumferential end of the outer hub 22 described in 11η so as to rotate together with the outer hub 22.

A low-friction member (for example, a needle bearing) 26 is interposed between the lower end of one of the sub-plates 24 and the outer circumference of the inner hub 21, which allows for relative rotation between the inner hub 2I and the outer hub 22. movement is smoothed. Furthermore, an annular plate-shaped friction member 27 is interposed between the sub-plate 24 and the inner hub 21. This friction member 27 provides a damping force due to frictional resistance to the relative rotation between the hubs 21 and 22. In this embodiment, in order to maintain a stable frictional contact state between the friction member 27 and the sub-plate 24 and the inner hub 21, an annular wave plate-like elastic member 28 is provided on the inner side of the other sub-plate 25. is attached, and this elastic member 28 applies a spring force to the pinching force of the friction member 27 between the sub-plate 24 and the inner hub 21, thereby obtaining a stable friction force.

On the other hand, on the outer periphery of the outer hub 22, there are 3 extending in the radial direction.
The hub arms 29 are formed and arranged at equal intervals in the circumferential direction, and the radial arms 6 of the floaters 62 are arranged between adjacent hub arms 29.
Coil springs 60 and 61 are arranged in series through 3. Hardened layers 29a and 63a are formed on the outer surfaces of the hub 20 (outer hub 22) and the floater 62 by shot peening or the like to improve mechanical strength and wear resistance. A drive plate 30 , 31 that substantially surrounds the outer circumferential side of the outer hub 22 and is arranged on both sides thereof has a window having a circumferential length that is the same as the circumferential length between adjacent hub arms 29 of the outer hub 22 . 32 are formed, and the circumferential end surfaces of these windows 32 engage coil springs 60, 61 housed between adjacent hub arms 29. Therefore, the outer hub 22
When the drive plate 30.31 and the drive plate 30.31 rotate relative to each other, the coil spring 60.31 housed between the adjacent hub arms 29.
61 act in series, and the spring groups acting in series act in parallel.

Between the outer hub 22 and the drive plate 30.31, specifically between the sub-plate 24.25 and the drive plate 30.31, which are integrally attached to the outer hub 22, there is a frictional resistance to their relative rotation. Friction members 34 and 35 are sandwiched to give the same. A disc spring 36 is located between the friction member 34 and the drive plate 30 and applies a stable axial pressing force to the friction members 34 and 35.

Note that the spring constant of the spring member 23 attached between the inner hub 21 and the outer hub 22 and the friction member 27
The coefficient of friction is relatively small and is effective in absorbing and damping torsional vibrations caused by torque fluctuations at low torque. Part 34.3
A friction coefficient of 5 is effective for absorbing and damping torsional vibrations caused by torque fluctuations when the torque is relatively large.

Next, the operation of the embodiment configured as above will be explained.

When this clutch disc l is assembled into a clutch device and the friction plate 40.40 is pressed against the flywheel of the engine (not shown), the driving torque 7 of the engine is transferred from the drive plate 30.31 to the coil spring 60.6.
1 to the hub 20, and is output to an output shaft (not shown).

At this time, the driving torque is first transmitted from the outer hub 22 to the inner hub 21 while bending the spring member 23 with a small spring force within a range in which the inner hub 21 and the outer hub 22 of the hub 20 can rotate relative to each other, The fluctuating torque in the low torque range is subjected to vibration absorption by the spring member 23 and damped by the friction member 27. Here, a low friction member 26 is provided between the inner hub 21 and the outer hub 22 to smooth the relative rotation thereof, and an elastic member 28 is provided to stabilize the friction member 27 that provides a friction damping force to the relative rotation. Since such a pressing force is applied, the vibration absorption and damping ability obtained when the inner hub 21 and the outer hub 22 rotate relative to each other becomes extremely stable.

Next, after the outer protrusion 21a of the inner hub 21 and the notch 22a of the outer hub 22 engage and their relative rotation stops, the inner hub 21 and the outer hub 22 become integral, and the drive plate 30 The drive torque input from the coil spring 60.61 is subjected to a vibration absorption effect by the coil spring 60.61, and is output to an output shaft (not shown) via the inner hub 21 while being subjected to a damping effect by the friction member 34.35. In this case, the coil spring 60.6
1 is configured as a group of springs that act in series between adjacent hub arms 21a of the outer hub 21, so the relative rotation angle between the drive plate 30.31 that engages with these coil springs 60.61 and the hub 20 is is large,
Demonstrates excellent vibration absorption and damping performance over a wide range of transmitted torque.

In the above embodiment, the friction member 24 was indirectly interposed between the inner hub 21 and the outer hub 22 via the sub-plate 24; It may be interposed so as to be in direct contact with. Further, the low-friction member 26 may be replaced by a low-friction material coating or plating of chromium, nickel, etc. between the sub-plate 24 and the inner hub 21. Further, both ends of the spring member 23 that elastically connects the inner hub 21 and the outer hub 22 are engaged with the inner hub 21 and the outer hub 22, respectively.
4 may be engaged with each other.

In addition, although this embodiment has been described using a clutch disk as an example, it can also be applied to a lock-up clutch of a torque converter as shown in FIGS. 4 and 5. That is,
A hardened layer 70a is formed on the outer surfaces of the hub 70 and the floater 71 by shot peening or the like.

71a can improve the durability of the lock-up clutch (torsional vibration damping device).

In the figure, 72.73 is a coil spring, 74°75
is the drive plate.

The hardened layers 29a, 63a, 70a, 71a may be formed on the entire floater 62.71 and the hub 20.70 by shot peening, but at least on the radial arm 63.71b and the hub arms 29, 70b. It may be formed on the outer surface.

Effects of the Invention As described above, in the present invention, a hardened layer is formed on the outer surface of at least one of the hub or the roller, which improves the mechanical strength of these and makes contact with the coil springs of the hub arm and the radial arm. The wear resistance of the surface is improved. Therefore, the spring force of the coil spring generated when the drive plate rotates relative to the hub prevents the hub or the idler from being prematurely worn out, deformed, and damaged.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a torsional vibration damping device showing an embodiment of the present invention, Fig. 2 is a partially cutaway front view of the same torsional vibration damping device, and Fig. 3 is a cross-sectional view of the torsional vibration damping device showing an embodiment of the present invention. FIG. 4 is a partially cutaway front view of a torsional vibration damping device showing another embodiment of the present invention, and FIG.
It is a sectional view taken along the line ■-■ in the figure. 20...Hub, 29.70...Hub arm, 29a
. 63a, 702L, 71a-hardened layer, 30, 31° 74
．． 75...Drive plate, 62...Player, 6
3.71...Radial arm, 2 people outside Fig. 1

Claims (1)

[Claims] (1) A hub that is provided with a plurality of hub arms in the circumferential direction that protrude outward in the radial direction, and an idler that is connected to the hub so as to be rotatable relative to the hub and that is provided with a radial arm that extends between adjacent hub arms. , a torsional vibration damping device comprising a coil spring that is interposed between the hub arm and the radial arm and connects the hub and the idler so that the hub and the idler can rotate relative to each other; A torsional vibration damping device characterized by having a hardened layer formed on its outer surface.