JPH06174011A - Damper device - Google Patents

Abstract

PURPOSE:To realize a compact size in the axial direction by providing curved leaf springs in a viscous fluid housing through specific clearances, and connecting the input part and the output part elastically. CONSTITUTION:A fluid chamber 17 is composed of a disk form input plate 6 provided at the side surface of a hub 5 at the engine side, an opposing plate 7 provided opposing to the input plate 6, and an output plate 12. While a viscous fluid such as a grease is housed in the fluid chamber 17, a pair of leaf springs 18 are housed there. And plural closed spaces 25 are formed between the opposing plate 7 and the curved leaf springs 18, and holes 24 to let flow out the viscous fluid accumulated in the closed spaces 25 are formed. Consequently, a vibration in the motive powder transmission can be attenuated, and a compact size in the axial direction can be realized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a damper device, and more particularly to
The present invention relates to a damper device that has a viscous fluid storage portion and damps vibrations by viscous fluid.

[0002]

2. Description of the Related Art For example, in a vehicle, a damper device is arranged between a member on the engine side and a member on the transmission side to absorb a torque fluctuation of the engine. The damper device attenuates torsional vibration (torque fluctuation) during power transmission, an input member and an output member that are rotatable relative to each other, a torsion spring that elastically connects the input member and the output member. And a vibration damping device.

Such a conventional damper device is disclosed, for example, in Japanese Patent Laid-Open No. 62-118124.
This device includes a first flywheel and a second flywheel that can rotate relative to each other, a coil spring that elastically connects both flywheels, and a viscous damping mechanism that is arranged between both flywheels. The first flywheel can be connected to a member on the engine side, and the second flywheel can be connected to a clutch device on the transmission side.

[0004]

In the conventional damper device described above, a coil spring as an elastic coupling mechanism and a damping mechanism for damping vibration are arranged. Here, the coil spring forming the damper device requires a space in the circumferential direction and the axial direction due to its structure. Therefore, it becomes difficult to incorporate the damper device as described above in a front-wheel drive vehicle in which the space in the axial direction is limited.

Further, in order to absorb torque fluctuations, especially under low load, it is necessary to reduce the torsional rigidity of the coil spring. Generally, in order to reduce the torsional rigidity of the coil spring, the wire diameter of the coil may be reduced, but if the wire diameter is reduced, the torque transmission capacity will be reduced.
Therefore, the coil diameter of the coil spring is increased to reduce the rigidity while maintaining the torque transmission capacity. For this reason, the volume occupied by the coil spring becomes large, which hinders miniaturization in the axial direction.

An object of the present invention is to reduce the size in the axial direction.

[0007]

SUMMARY OF THE INVENTION A damper device according to the present invention includes a rotatable input section, an output section rotatable relative to the input section, and an internal section disposed between the input section and the output section. A viscous fluid storage portion that stores the viscous fluid, and a bending leaf spring that is stored in the viscous fluid storage portion via a predetermined gap and that elastically connects the input portion and the output portion are provided.

A hole through which a viscous fluid can pass may be provided in a part of the bent leaf spring.

[0009]

In the damper device according to the present invention, when the input portion rotates, the power is transmitted to the output portion via the bent leaf spring arranged in the viscous fluid storage portion. Since the width of the bent leaf spring can be made smaller than that of the coil spring, the axial direction of the entire device can be made smaller.

Further, since the bending leaf spring expands and contracts in the viscous fluid storage portion, the expansion and contraction causes the viscous fluid to pass through the gap between the bending leaf spring and the viscous fluid storage portion, and a predetermined viscous damping force is generated. Thereby, hysteresis corresponding to the cross-sectional area of the gap is obtained. In this way, both functions of the conventional elastic coupling mechanism and vibration damping mechanism can be realized by the viscous fluid container and the bent leaf spring housed in this container, and the size of the device can be further reduced.

When a hole through which the viscous fluid can pass is formed in a part of the bending leaf spring, when the bending leaf spring is compressed, the closing formed between the viscous fluid storage portion and the bending leaf spring. The viscous fluid present in the space flows out through the holes.
Therefore, when the bending leaf spring is compressed, the bending leaf spring can be prevented from being deformed in the radial direction, and the closed space can be maintained. Therefore, the clearance between the bent leaf spring and the viscous fluid storage portion can be maintained at a preset clearance, and a desired large viscous damping force can be obtained.

[0012]

1 and 2 show a flywheel assembly in which a damper device according to an embodiment of the present invention is adopted. In the figure, OO is a center line. This flywheel assembly includes a first flywheel 1 fixed to a crankshaft (not shown) and a second flywheel 3 rotatably supported by the first flywheel 1 via a bearing 2.
And have. The clutch disc 4 is pressed against the second flywheel 3.

The first flywheel 1 is arranged so as to face the input plate 6 and a hub 5 arranged in the central portion, a disc-shaped input plate 6 arranged on a side surface of the hub 5 on the engine side. The counter plate 7 and the annular first flywheel body 8 fixed to the outer peripheral portion of the input plate 6. The hub 5 and the input plate 6 are fixed to the crankshaft by bolts 9 and washer plates 10. The outer peripheral portion 7 a of the counter plate 7 is bent toward the input plate 6 side and inserted into the inner peripheral portion of the first flywheel body 8. The tip of the bent portion 7a is fixed to the outer peripheral portion of the input plate 6 and the inner peripheral portion of the first flywheel body 8 by welding. A ring gear 11 is fixed to the outer periphery of the first flywheel body 8.

The second flywheel 3 is the output plate 1
2, an annular second flywheel main body 13, and a disc-shaped intermediate plate 14 arranged between the output plate 12 and the second flywheel main body 13,
These are connected by a plurality of rivets 15. The output plate 12 is composed of an inner peripheral support portion 12a supported by the bearing 2 and a mounting portion 12b extending from the support portion 12a to the outer peripheral side. The support portion 12a is in contact with one side surface and the outer peripheral surface of the bearing 2. Then, as shown in an enlarged manner in FIG. 3, a seal member 16 is arranged between the outer peripheral portion of the mounting portion 12b and the inner peripheral portion of the counter plate 7 for sealing the both. Also, the intermediate plate 1
The inner peripheral portion of 4 is in contact with the other side surface of the bearing 2.

With the above structure, the input plate 6, the counter plate 7 and the output plate 12 form a fluid chamber 17. A viscous fluid such as grease is contained in the fluid chamber 17, and a pair of curved leaf springs 1
8 are accommodated. As shown in FIG. 4, the bent leaf spring 18 is formed by connecting a plurality of spring elements including a ring portion 20 and a lever portion 21 in series. The spring elements are connected by a lever portion 21.

The plurality of ring portions 20 are arranged on opposite sides. Each ring portion 20 is an annular body having substantially the same diameter, and a predetermined gap δ ₁ is provided between adjacent ring portions 20 in a free state. The inside of the ring portion 20 is an open ring portion 23. A gap δ ₂ is formed in the open ring portion 23 in the free state and the set state, and the lever portions 21 extend outward from both sides of the open ring portion 23, respectively. The lever portions 21 extend so that the distance between them expands toward the outside, and the lever portions 2 of the opposing ring portions 20.
It is continuous to one side of 1.

The width of the bent leaf spring 18 is set to the fluid chamber 17
Is substantially equal to the width of the fluid chamber 17 and its radial length is smaller than the length of the fluid chamber 17. Such a bent leaf spring 18 is provided in the fluid chamber 17
In the case of being mounted on, the plurality of closed spaces 25 are formed between the facing plate 7 and the bent leaf spring 18, as shown in FIG. A hole 24 is formed in a part of the lever portion 21 of the bent leaf spring 18 for letting out the viscous fluid stored in a part of the closed space 25. In this embodiment, the holes 24 are formed in the plurality of closed spaces 25 so that every other fluid in the closed spaces 25 flows out.

Further, as shown in FIGS. 1 and 2, the outer peripheral portion of the counter plate 7 is formed with engaging portions 7b projecting toward the inner peripheral side at two opposing locations. The locking portion 7b is locked to the ring portion 20 on the outer peripheral side of the bent leaf spring 18. Further, on the outer peripheral portion of the support portion 12a of the output plate 12, there are locking portions 12c projecting to the outer peripheral side at two opposing locations.
Are formed. The locking portion 12c is locked to the ring portion 20 on the inner peripheral side of the bent leaf spring 18. With such a configuration, the power input to the first flywheel 1 is transmitted to the second flywheel 3 via the bent leaf spring 18.

Next, the operation will be described. The torque transmitted from the crankshaft of the engine to the first flywheel 1 is transmitted to the bending leaf spring 18 via the engagement portion 7b of the input plate 6 and the counter plate 7, and further, the bending leaf spring 18 outputs the torque to the output plate 12. It is transmitted to the second flywheel 3 via the locking portion 12c. At this time, the bent leaf spring 16 is compressed between the counter plate 7 and the output plate 12.

When the bending leaf spring 16 is compressed, the opening angle of each lever portion 21 becomes small and a bending moment acts on the ring portion 20. At this time, the lever portion 21 bends around the ring opening portion 23 as a fulcrum. Then, the bending moment is uniformly distributed in the lever portion 21 in the longitudinal direction, and elastic energy is dispersed and stored in the plurality of ring portions 20.

The torsional characteristics in this case are as follows:
It is determined by the torsional rigidity of 8. That is, in a small twisting angle range where there is a gap δ ₂ in the ring-opening portion 23, the ring portion 20 and the lever portion 21 bend and twist in the same direction with the outer peripheral portion of the ring portion 20 of the bending leaf spring 18 as a fulcrum. The rigidity is small. On the other hand, when the twisting angle increases, the gap δ ₂ becomes 0, and elastic energy is stored in the ring portion 20 with the ring-opening portion 23 as a fulcrum, so that the torsional rigidity increases.

By using such a bent leaf spring, for example, if the width is 13 mm and the length is 44 mm, 50 kg.
A stopper torque of m can be obtained. On the other hand, in the conventional coil spring having a coil diameter of 28 mm, the stopper torque is limited to 36 kgm. When the bending leaf spring 18 expands and contracts in the fluid chamber 17 as described above, the viscous fluid circulates through the gap between the bending leaf spring 18 and the fluid chamber 17,
A vibration damping force (hysteresis) is generated by the viscous force. This hysteresis will be described in detail with reference to FIG.

As shown in FIG. 5, in the shaded region A of the plurality of closed spaces 25, no holes are formed in the lever portion 21 forming the closed spaces 25. Therefore, when the bent leaf spring 18 expands and contracts, the viscous fluid flows through a small gap between the bent leaf spring 18 and the fluid chamber 17, and a large hysteresis occurs. On the other hand, in the other region B of the plurality of closed spaces 25,
A hole 24 is formed in the lever portion 21. Therefore,
Viscous fluid flows through the holes 24, and the hysteresis is small.

Here, the power transmission system constituted by the fluid contained in the fluid chamber 17 and the bent leaf spring 18 is schematically shown in FIG. In FIG. 6, K
Reference numeral 1 is a spring component formed by the portion of region B in FIG. 5, and K2 is a spring component formed by the portion of region A. Further, C is a viscous damping force generating portion formed by the portion of the area A. In FIG. 6, the viscous force Fc
And the spring force Fk are as follows: Fc = C · dθ / dt dθ / dt: rotational angular velocity Fk = K · θθ: rotational angular displacement In the above configuration, an incompressible viscous fluid is contained in the region A portion. Since the gap is small, the spring force in the area A is small and the viscous force (hysteresis) is large. That is, Fc >> Fk2. For this reason,
The spring component K2 in FIG. 6 becomes negligible, and the spring force and the viscous damping force of the spring component K1 act in series. Therefore, it is possible to eliminate resonance in the present device including the two flywheels 1 and 3.

If the hole 24 is not formed in a part of the bending leaf spring 18, the bending leaf spring 18 is separated from the outer peripheral portion 7a of the counter plate 7 because the viscous fluid is incompressible. Deforms to the inner circumference side. In this case, the gap through which the viscous fluid flows becomes large, the desired viscous damping force cannot be obtained, and as described above, the power transmission system in which the spring force and the viscous damping force act in series cannot be realized.

In this embodiment, the bent leaf spring 1 is used.
By using No. 8, the axial dimension can be made smaller than that of the conventional coil spring. In addition, the conventional torsion spring and hysteresis generation mechanism,
Since it can be configured by the fluid chamber 17 and the bent leaf spring 18, the configuration is very simple and inexpensive. [Other Embodiments] In the above embodiment, the gap δ ₂ is formed in the ring opening portion 23 when the bent leaf spring is set. However, the gap δ ₂ of the ring opening portion 23 is set to "0" at the time of setting. It may be.

[0027]

As described above, in the damper device according to the present invention, the bending leaf spring is housed in the viscous fluid housing portion formed between the input portion and the output portion, and the bending portion is provided between the input portion and the output portion. Since the connection is made by the spring and the vibration is damped by the viscous fluid flowing through the gap between the viscous fluid storage portion and the curved leaf spring, the size can be reduced particularly in the axial direction.

[Brief description of drawings]

FIG. 1 is a partial vertical cross-sectional view of a flywheel assembly according to an embodiment of the present invention.

FIG. 2 is a partial front sectional view of the flywheel assembly.

FIG. 3 is a partially enlarged view of FIG.

FIG. 4 is a front view of a bent leaf spring.

5 is a partially enlarged view of FIG.

FIG. 6 is a schematic diagram of a power transmission system of the flywheel assembly.

[Explanation of symbols]

 1 First Flywheel 3 Second Flywheel 6 Input Plate 7 Opposing Plate 12 Output Plate 14 Intermediate Plate 17 Fluid Chamber 18 Bending Leaf Spring 24 Hole

Claims (3)

[Claims] 1. A rotatable input part, an output part rotatable relative to the input part, and a viscous fluid storage part disposed between the input part and the output part for storing a viscous fluid therein. And accommodated in the viscous fluid container via a predetermined gap,
A damper device comprising: a bent leaf spring that elastically connects the input section and the output section. 2. The damper device according to claim 1, wherein the bent leaf spring partially has a hole through which a viscous fluid flows. 3. The bent leaf spring is formed by connecting a plurality of spring elements in series, and the spring element includes a ring portion having an open ring portion in a part thereof, and an outward ring portion from the open ring portion. The damper device according to claim 1, further comprising a pair of lever portions extending so as to be spaced apart from each other.