JP2818084B2 - Damper device and flywheel assembly - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a damper device,
The present invention relates to a damper device having a viscous fluid storage unit and attenuating vibration due to the viscosity of a fluid. Also, this damper device
A flywheel assembly having the same.

[0002]

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

[0003] Such a conventional damper device is disclosed, for example, in JP-A-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 the two flywheels, and a viscous damping mechanism disposed between the two flywheels. The first flywheel is connectable to a member on the engine side, and the second flywheel is connectable to a clutch device on the transmission side.

[0004]

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

[0005] Further, in order to absorb a torque fluctuation under a low load, it is necessary to lower the torsional rigidity of the coil spring. Generally, to reduce the torsional rigidity of the coil spring, the wire diameter of the coil may be reduced. However, when the wire diameter is reduced, the torque transmission capacity is 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, particularly in the axial direction.

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

[0007]

According to a first aspect of the present invention, there is provided a damper device comprising: a rotatable input member ; an output member rotatably disposed relative to the input member;
A viscous fluid storage unit disposed between the output side member and storing the viscous fluid therein; and an input side stored in the viscous fluid storage unit.
A bent leaf spring elastically connects the member and the output side member in the rotational direction . And the bent leaf spring is elastic
A plurality of spring elements having a ring portion and a pair of lever portions;
They are connected so as to operate in series. Elasticity
The ring has a ring opening part, and both ends approach each other
It is a fulcrum. A pair of levers are outward from both ends
Extend so that the distance between each other increases toward
Receiving external force in the direction approaching each other and forming a through hole
Have been. The flywheel assembly according to claim 2 is
The damper device according to claim 1 and an input side member.
And a first flywheel connected to the output side member.
And two flywheels.

[0008]

[0009]

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

Further, since the undulated plate spring expands and contracts with a viscous fluid containing portion, the gap between the curved leaf spring and the viscous fluid containing portion by the expansion and contraction through viscous fluid, viscous damping force. Thereby, hysteresis according to the cross-sectional area of the gap is obtained. As described above, both functions of the conventional elastic coupling mechanism and the vibration damping mechanism can be realized by the viscous fluid storage portion and the bent leaf spring stored in the storage portion, and the size of the apparatus can be further reduced.

Further , since a through hole through which the viscous fluid can pass is formed in a part of the curved leaf spring, when the curved leaf spring is compressed, a through hole is formed between the viscous fluid accommodating portion and the curved leaf spring. The viscous fluid existing in the closed space flows out through the holes. Therefore, when the bent leaf spring is compressed, the bent leaf spring can be prevented from being deformed in the radial direction, and a closed space can be maintained. Therefore, the gap between the bent leaf spring and the viscous fluid container can be maintained at a preset gap,
A desired large viscous damping force is obtained.

[0012]

1 and 2 show a flywheel assembly employing a damper device according to one embodiment of the present invention. In the figure, OO is a center line. The 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 A clutch disc 4 is pressed against the second flywheel 3.

The first flywheel 1 is arranged at a center portion of a hub 5, a disc-shaped input plate 6 arranged on a side of the hub 5 on the engine side, and is arranged to face the input plate 6. And an annular first flywheel body 8 fixed to the outer periphery 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 opposing plate 7 is bent toward the input plate 6 and inserted into the inner peripheral portion of the first flywheel body 8. The distal end 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 an outer peripheral portion of the first flywheel body 8.

The second flywheel 3 includes an output plate 1
2, an annular second flywheel main body 13, and a disk-shaped intermediate plate 14 disposed 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 includes a support portion 12a of an inner peripheral portion 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 for sealing both is provided between the outer peripheral portion of the mounting portion 12b and the inner peripheral portion of the opposed plate 7. Also, the intermediate plate 1
The inner peripheral portion of the bearing 4 is in contact with the other side surface of the bearing 2.

With the above structure, the fluid chamber 17 is constituted by the input plate 6, the opposed plate 7, and the output plate 12. The fluid chamber 17 contains a viscous fluid such as grease and a pair of bent 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. Each spring element is connected by a lever part 21.

The plurality of ring portions 20 are arranged on opposite sides. Each ring portion 20 is substantially the same diameter annulus, between each adjacent ring portions 20, and has a predetermined gap [delta] ₁ in a free state. The inside of the ring portion 20 is a ring opening portion 23. A gap δ ₂ is formed in the ring opening portion 23 in the free state and the set state, and the lever portions 21 extend outward from both sides of the ring opening portion 23. The lever portions 21 extend so that the interval between them increases toward the outside.
1 is continuous.

The width of the bent leaf spring 18 is
And the length in the radial direction is smaller than the length of the fluid chamber 17. Such a bent leaf spring 18 is connected to the fluid chamber 17.
5, a plurality of closed spaces 25 are formed between the opposing plate 7 and the curved 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 to allow the viscous fluid accumulated in a part of the closed space 25 to flow out. In this embodiment, holes 24 are formed in a plurality of closed spaces 25 so that the fluid in the closed spaces 25 flows out every other space.

As shown in FIGS. 1 and 2, on the outer peripheral portion of the opposing plate 7, locking portions 7b projecting inward are formed 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, locking portions 12c protruding outward at two locations facing each other are provided on the outer peripheral portion of the support portion 12a of the output plate 12.
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 curved leaf spring 18.

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

When the bent 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 longitudinal direction in the lever portion 21, and the elastic energy is dispersed and stored in the plurality of ring portions 20.

The torsion characteristics in this case are as follows.
8 torsional stiffness. That is, in the small torsion angle range having the gap δ ₂ in the ring opening portion 23, the ring portion 20 and the lever portion 21 bend in the same direction with the outer peripheral portion of the ring portion 20 of the bent leaf spring 18 as a fulcrum, and Rigidity is small. On the other hand, when the torsional angle increases, the gap δ ₂ becomes zero, and elastic energy is stored in the ring portion 20 with the ring opening 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
m stopper torque is obtained. On the other hand, in a conventional coil spring having a coil diameter of 28 mm, for example, the stopper torque is 36 kgm. When the bent leaf spring 18 expands and contracts in the fluid chamber 17 as described above, the viscous fluid flows through the gap between the bent leaf spring 18 and the fluid chamber 17,
The viscous force produces a vibration damping force (hysteresis). This hysteresis will be described in detail with reference to FIG.

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

Here, a schematic diagram of a power transmission system constituted by the fluid accommodated in the fluid chamber 17 and the bent leaf spring 18 is shown in FIG. In FIG. 6, K
Reference numeral 1 denotes a spring component formed by the portion of the region B in FIG. 5, and K2 denotes a spring component formed by the portion of the region A. C is a viscous damping force generating portion formed by the portion of the region A. In FIG. 6, the viscous force Fc
Fc = C · dθ / dt dθ / dt: rotational angular velocity Fk = K · θθ: rotational angular displacement In the above configuration, the incompressible viscous fluid is contained in the area A. Therefore, since the gap is small, the spring force in the region A is small and the viscous force (hysteresis) is large. That is, Fc >> Fk2. For this reason,
The spring component K2 in FIG. 6 can be ignored, and the spring force and the viscous damping force by the spring component K1 act in series. For this reason, it is possible to eliminate resonance in the present apparatus having the two flywheels 1 and 3.

When the hole 24 is not formed in a part of the curved leaf spring 18, the curved leaf spring 18 is separated from the outer peripheral portion 7a of the opposing plate 7 because the viscous fluid is incompressible. Deforms inward. In this case, the gap through which the viscous fluid flows becomes large, and a desired viscous damping force cannot be obtained. As described above, a 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 8, the axial dimension can be reduced as compared with the conventional coil spring. Also, the conventional torsion spring and the hysteresis generation mechanism
Since it can be constituted by the fluid chamber 17 and the bent leaf spring 18, the structure is very simple and the cost is low. In Other Embodiments The embodiment, when a set of undulated plate spring, but the opening portion 23 configured to clearance [delta] ₂ is formed, a gap [delta] ₂ of the opening portion 23 when the set is "0 ".

[0027]

In the damper device according to the present invention as described above, according to the present invention accommodates a bent plate spring to the viscous fluid containing portion formed between the input member and the output member, the input-side member and the output-side member And connected by a bent leaf spring,
Vibration is attenuated by the viscous fluid flowing through the gap between the viscous fluid accommodating portion and the bent leaf spring, so that the size can be reduced particularly in the axial direction. In addition, the bent leaf spring
Since a hole is formed in the lever, when the bent leaf spring is compressed
This prevents the bent leaf spring from deforming in the radial direction.
Thus, a desired viscous damping force is obtained.

[Brief description of the drawings]

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

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

FIG. 3 is a partially enlarged view of FIG. 1;

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

FIG. 5 is a partially enlarged view of FIG. 2;

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st flywheel 3 2nd flywheel 6 Input plate 7 Opposing plate 12 Output plate 14 Intermediate plate 17 Fluid chamber 18 Curved leaf spring 24 hole

Claims (2)

(57) [Claims] An input member rotatable and an output rotatably disposed relative to the input member .
And side members, wherein arranged between the input-side member and the output-side member, and the viscous fluid accommodating portion for accommodating a viscous fluid therein, is accommodated in the fluid receptacle, the input-side member and the front
A bent leaf spring for elastically connecting the output side member to the output side member in the rotation direction , wherein the bent leaf spring has a ring-opening portion in part, and both ends serve as fulcrums that approach each other.
Elastic ring portion, the distance between each other as going outward from the both ends
Extends to spread and receives external force in the direction approaching each other.
And a pair of lever portions each having a through hole formed therein.
Multiple spring elements connected in series
What is a damper device. 2. A flywheel assembly comprising: the damper device according to claim 1; a first flywheel connected to the input member; and a second flywheel connected to the output member. .