JPH074497A - Hydraulic power transmission with lock-up clutch - Google Patents

Abstract

PURPOSE:To give a high transmission torque capacity and a high torque variation attenuation compatibly while realizing a compact size, in a hydraulic power transmission device with a lock-up clutch which is used for the driving system of an automobile. CONSTITUTION:A lock-up clutch is made in a multi-plate lock-up clutch 9 having three clutch sliding surfaces, and a tortion damper 10 (a twist damper) is provided on the outer diameter side from the multi-plate lock-up clutch 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic power transmission device with a lockup clutch used in a drive system of an automobile.

[0002]

2. Description of the Related Art Conventionally, as a torque converter with a lockup clutch, for example, one disclosed in Japanese Patent Laid-Open No. 55-54758 is known.

In the above-mentioned conventional publication, as shown in FIG. 3, in a torque converter 101 having a pump impeller 102, a turbine runner 103 and a stator 104, a clutch is provided in a space formed between the turbine runner 103 and a converter cover 105. A piston 108 is arranged, a multi-plate lock-up clutch 106 is provided between the upper portion of the piston 108 and the converter cover 105, and a torsion damper 107 as a torsion damper for damping torsional vibration of the engine is provided from the multi-plate lock-up clutch 106. It is shown incorporated into the clutch piston 108 on the inner diameter side.

[0004]

However, in the above conventional technique, the multi-plate lockup clutch 106 is used.
As shown in FIG. 3, the layout relationship between the torsion damper 107 and the torsion damper 107 is such that the clutch engagement piston 108 is arranged on the inner diameter side of the multi-plate lockup clutch 106, so that there are problems listed below.

(1) If the wire diameter of the torsion damper 107 and the outer diameter of the spring are increased, both high transmission torque and high damping of torque fluctuation can be achieved, but the torsion damper 107 becomes large.
The torque converter 101 becomes long in the axial direction and lacks compactness.

(2) If the wire diameter of the torsion damper 107 and the outer diameter of the spring are reduced, the compactness can be achieved, but the desired torque fluctuation damping effect cannot be obtained.

That is, because the torsion damper 107 is arranged on the inner diameter side of the multi-plate lockup clutch 106, it is not possible to sufficiently secure the torsion radius r from the rotation axis to the torsion damper 107. Further, when the spring pressing force is F, it is expressed as ΔT = F · r. Therefore, if the torsion radius r is small, a predetermined fluctuation torque Δ
The spring pressing force F with respect to T becomes large.

Therefore, in order to obtain the torsion angle θ which secures the fluctuation damping effect with respect to the fluctuation torque ΔT, the wire diameter of the torsion damper 107 and the outer diameter of the spring are set to a high spring constant to set a large spring pressing force F. I have no choice but to counter.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a fluid transmission device with a lockup clutch for use in a drive system of an automobile, which is compact and yet has a compact structure. It is to achieve both high transmission torque capacity and high torque fluctuation damping.

[0010]

In order to achieve the above object, in a fluid transmission device with a lock-up clutch of the present invention, the lock-up clutch is a multi-plate lock-up clutch having two or more clutch sliding surfaces, and twisting is performed. The damper was arranged on the outer diameter side of the multi-plate lockup clutch.

That is, a pump impeller connected to an input shaft via a cover, a turbine runner arranged to face the pump impeller and connected to an output shaft, and a chamber formed by the cover and the turbine runner is a clutch. A lock-up clutch is defined by a piston into a lock-up chamber and a vane element chamber, and the lock-up clutch allows the input / output shaft to be directly connected by fastening by reducing the pressure in the lock-up chamber, and is transmitted when the lock-up clutch is directly connected. And a torsion damper provided in the middle of a torque transmission path, wherein the lockup clutch is a multi-plate lockup clutch having two or more clutch sliding surfaces, and The damper is placed on the outer diameter side of the multi-plate lockup clutch.

[0012]

When the lockup is performed, the pressure in the lockup chamber defined by the clutch piston is reduced, so that the lockup clutch is engaged by the pressure difference between the oil pressure from the blade element chamber acting on the clutch piston and the input shaft. The output shaft is directly connected via a lockup clutch, and the fluid torque transmission state by the pump impeller and the turbine runner is changed to the direct coupling torque transmission state.

In this direct-coupling torque transmission state, torque transmission with a sufficient transmission torque capacity without slippage of the lock-up clutch is required for high transmission torque, and fluctuations in transmission torque are also absorbed by fluid slippage. Instead, damping by a torsion damper provided in the middle of the torque transmission path is required.

To meet the former requirement for the transmission torque capacity, the lockup clutch is a multi-plate lockup clutch having two or more clutch sliding surfaces.
If the multi-disc lockup clutch with two clutch sliding surfaces does not reach the required transmission torque capacity, the number of clutch sliding surfaces can be increased to three or four to meet the high transmission torque capacity requirement. .

Regarding the latter torque fluctuation absorption, by disposing the torsion damper on the outer diameter side of the multi-plate lockup clutch, a sufficient torsion radius from the axis of rotation to the torsion damper is ensured and a predetermined value is obtained. The pressing force against the fluctuating torque is reduced. Therefore, in order to obtain a torsion angle that achieves sufficient damping of torque fluctuation, the torsion damper can be made compact with a small spring constant.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

First, the structure will be described.

FIG. 1 is an overall sectional view showing a torque converter with a lockup clutch (an example of a hydraulic power transmission with a lockup clutch) according to an embodiment of the present invention.

In FIG. 1, 1 is a torque converter with a lockup clutch, 2 is a pump impeller, 3 is a turbine runner, 4 is a stator, 5 is a cover cover (corresponding to a cover), 6 is a clutch piston, 7 is a lockup chamber, Reference numeral 8 is a converter chamber (corresponding to a blade element chamber), 9 is a multi-plate lockup clutch, and 10 is a torsion damper (corresponding to a torsion damper).

The pump impeller 2 is connected to a crankshaft (input shaft) (not shown) via a converter cover 5.

The turbine runner 3 is arranged so as to face the pump impeller 2, and a transmission input shaft (output shaft) (not shown) is spline-connected to a turbine hub 11 for fixing the turbine runner 3.

The stator 4 is a one-way clutch 1.
The one-way clutch 12 is fixed to the outer race 2 and the transmission case (not shown) is spline-connected to the inner race of the one-way clutch 12.

The clutch piston 6 defines a chamber formed by the converter cover 5 and the outer shell of the turbine runner 3 into a lockup chamber 7 and a converter chamber 8. Here, the inner diameter portion 6a of the clutch piston 6 is
The turbine hub 11 can be slid in an oil-tight state without being splined.

The multi-plate lock-up clutch 9 is interposed between the converter cover 5 and the clutch piston 6, and is engaged by reducing the pressure in the lock-up chamber 7 to convert the converter cover 5 into the multi-plate lock-up clutch 9.
→ A direct connection torque transmission path extending from the torsion damper 10 → the turbine runner 3 → the turbine hub 11 is formed.

The torsion damper 10 is interposed between the upper end of the clutch piston 6 and the outer shell of the turbine runner 3, and is arranged on the outer diameter side of the multi-plate lockup clutch 9 in layout.

The torsion damper 10 is fixed to the upper end of the clutch piston 6 and has a plurality of spring insertion spaces in the circumferential direction, and the torsion damper 10 is fixed to the outer shell of the turbine runner 3 and is rotated relative to the variable torque input. Press plate 1 to compress the spring with
0b and a coil spring 10c inserted between the guide plate 10a and the pressing plate 10b.

FIG. 2 is an enlarged sectional view of the multi-plate lockup clutch.

In FIG. 2, the multi-plate lock-up clutch 9 has a first clutch disc 9a splined to the converter cover 5 side, a second clutch disc 9b splined to the clutch piston 6 side, and a first clutch disc 9b.
The first friction pad 9c and the second friction pad 9d attached to both sides of the clutch disc 9a, and the third friction pad 9e attached to the converter cover 5 side of the second clutch disc 9b are used to form a clutch sliding surface. It has a three-sided clutch structure.

The spline teeth 9f of the first clutch disc 9a are spline-coupled with the spline teeth 9h formed on the first annular member 9g fixed to the converter cover 5. The spline teeth 9i of the second clutch disc 9b are spline-coupled with the spline teeth 9k formed on the second annular member 9j fixed to the clutch piston 6.

Next, the operation will be described.

[During non-lockup] When torque transmission by the torque converter is desired at the time of starting the vehicle or the like, hydraulic oil is directed from the lockup chamber 7 to the converter chamber 8 and both clutch discs 9a-of the multiple disc lockup clutch 9 are supplied. 9
The release state of the multi-plate lockup clutch 9 is maintained, and all input torque from the engine is transmitted through the torque converter.

At the time of non-lockup, the effect of increasing the torque by fixing the stator 4 and the effect of absorbing the torque fluctuation due to fluid slippage are enjoyed.

[Lock-up] When torque transmission by direct connection is desired during high-speed running while shifting to a high-speed stage, the pressure in the lock-up chamber 7 defined by the clutch piston 6 is reduced by a drain or the like. By that,
A differential pressure is applied to the hydraulic pressure from the converter chamber 8 which acts on the clutch piston 6, and the multi-plate lockup clutch 9 is engaged by the force of this differential pressure, and the converter cover 5 to which the crankshaft is connected and the transmission input shaft. The turbine runner 3 to which is connected is directly connected via the multi-plate lock-up clutch 9, and the fluid torque transmission state by the pump impeller 2 and the turbine runner 3 is changed to the direct torque transmission state.

In this direct-coupling torque transmission state, the multi-plate lockup clutch 9 responds to high transmission torque from the engine.
Torque transmission with sufficient transmission torque capacity without slippage is required, and fluctuations in transmission torque from the engine are not absorbed by fluctuations due to fluid slip but are damped by a torsion damper 10 provided in the middle of the torque transmission path. Is required.

[Steady torque transmission action] With respect to the transmission torque capacity requirement at the time of lock-up, the multi-disc lockup clutch 9 having three clutch sliding surfaces is used as the lockup clutch, so that a high transmission torque capacity requirement is obtained. Can respond to.

That is, since the multi-plate lockup clutch 9 is arranged at the inner diameter position of the torsion damper 10, the transmission torque is greater than that when the torsion dampers having the same number of clutch sliding surfaces are inside the lockup clutch. There is a slight disadvantage in capacity. However, in the multi-disc lockup clutch 9, the number of clutch sliding surfaces can be freely set. For example, it is a vehicle equipped with a high-power engine, and as in the embodiment, the multi-disc lockup clutch has three sliding surfaces. In No. 9, if the required transmission torque capacity is not reached, the transmission torque capacity request can be met by increasing the number of clutch sliding surfaces to four or five.

[Fluctuating Torque Absorbing Action] In order to absorb torque fluctuation during lockup, the torsion damper 10 is arranged on the outer diameter side of the multi-plate lockup clutch 9 for the following reason. The torsion damper 10 can be made into a compact size with a small spring constant in order to obtain a torsion angle that achieves sufficient damping of

First, the torsion radius R from the rotational axis to the torsion damper 10 is sufficiently secured, and the spring pressing force f with respect to a predetermined fluctuation torque ΔT is reduced.

That is, since there is a relation of (fluctuation torque) = (spring pressing force) .multidot. (Torsion radius), if the fluctuation torque .DELTA.T is the same, the spring pressing amount is increased by the amount corresponding to the larger torsion radius R (> r). The force f (<F) becomes smaller.

Secondly, when the number of coil springs 10c provided in the circumferential direction of the torsion damper 10 is the same, the length of the coil spring 10c increases as the torsion radius R from the axis of rotation to the torsion damper 10 increases. It can be taken long.

Thirdly, in the case of the same twist angle, the larger the twist radius R from the rotation axis to the torsion damper 10, the greater the amount of bending of the coil spring 10c.

Next, the effect will be described.

(1) In the torque converter 1 with a lockup clutch used in a drive system of an automobile, the lockup clutch is a multi-plate lockup clutch 9 having three clutch sliding surfaces, and the torsion damper 1 is used.
Since 0 is arranged on the outer diameter side of the multi-plate lock-up clutch 9, it is possible to achieve both high transmission torque capacity and high damping of torque fluctuation while being compact.

(2) Since the torsion damper 10 is provided in the converter chamber 8, the torsion damper 10 is not required to have a hermetically sealing property, which simplifies the structure.

That is, since the conventional torsion damper is provided in the middle of the clutch piston so as to straddle the lockup chamber and the converter chamber, it is necessary to cover the torsion damper with a hermetic seal cover in order to define both chambers. .

(3) Since the torque transmission path at the time of lockup is different from the conventional one, the clutch piston 6 and the turbine hub 11 can simply slide in an oil-tight state, so the lockup chamber 7 and the converter chamber It is possible to improve the oil-tight sealing property with 8.

That is, since the torque transmission path at the time of lockup is conventionally the clutch piston → turbine hub and both are spline-coupled, it is difficult to reliably suppress the oil leakage from the spline-coupled portion. It was

Although the embodiments have been described above with reference to the drawings, the specific configuration is not limited to the embodiments, and modifications and additions within the scope of the present invention are included in the present invention. Be done.

For example, in the embodiment, the example of the torque converter is shown as the fluid transmission device, but a fluid coupling without a stator may be used.

In the embodiment, the multi-plate lock-up clutch is shown by using two clutch discs, but it may be one (three clutch sliding surfaces) or three or more.

[0051]

As described above, according to the present invention, in a hydraulic power transmission device with a lockup clutch used in a drive system of an automobile, the lockup clutch has a multi-disc lock having two or more clutch sliding surfaces. As an up clutch and a means in which the torsion damper is arranged on the outer diameter side of the multi-plate lock-up clutch, it is possible to achieve both high transmission torque capacity and high torque fluctuation damping while being compact. Is obtained.

[Brief description of drawings]

FIG. 1 is an overall sectional view showing a torque converter with a lockup clutch according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view showing a multi-plate lockup clutch of the embodiment torque converter.

FIG. 3 is an overall sectional view showing a conventional torque converter with a lockup clutch.

[Explanation of Codes] 1 torque converter with lockup clutch (fluid transmission with lockup clutch) 2 pump impeller 3 turbine runner 4 stator 5 coverta cover (cover) 6 clutch piston 7 lockup chamber 8 converter chamber (blade element chamber) 9 Multi-plate lock-up clutch 10 torsion damper (torsion damper)

Claims (1)

[Claims] 1. A pump impeller connected to an input shaft through a cover, a turbine runner connected to the pump impeller and connected to an output shaft, and a chamber formed by the cover and the turbine runner is a clutch. A lock-up clutch is defined by a piston into a lock-up chamber and a vane element chamber, and the lock-up clutch makes it possible to directly connect the input and output shafts by fastening by reducing the pressure in the lock-up chamber; And a torsion damper provided in the middle of a torque transmission path, wherein the lockup clutch is a multi-plate lockup clutch having two or more clutch sliding surfaces, and A locker characterized in that the damper is arranged on the outer diameter side of the multi-plate lockup clutch. Fluid transmission with clutch.