JPH0650128B2 - Power transmission device - Google Patents

Description

The present invention relates to a power transmission device mainly used as a starting device for a vehicle, and more particularly to a power transmission device in which a fluid coupling and a power cutoff clutch are arranged in series. .

[Conventional technology]

2. Description of the Related Art Conventionally, a power transmission device having a fluid coupling has been used as a starting device for a vehicle, and one example of such a power transmission device is disclosed in Japanese Patent Laid-Open No. 55-69355. In this device, the fluid coupling and the power cut-off clutch having a disc spring as an engaging means are arranged in series.

[Problems to be solved by the invention]

However, in the above-mentioned conventional device, since the fluid coupling and the power cutoff clutch are arranged in series with each other, the axial dimension is large, and the axial dimension is limited as in the case of mounting on a front engine front drive vehicle, for example. When it is severe, it is disadvantageous in terms of vehicle mountability. From this point of view, it can be considered to arrange the power cutoff clutch radially inside the turbine blade and the pump blade and incorporate it in the fluid coupling to reduce the axial dimension.

However, when the power cutoff clutch is arranged inside the turbine blade and the pump blade in the radial direction and incorporated in the fluid coupling, the power cutoff clutch has a smaller diameter than the conventional one, and the area of the friction surface of the power cutoff clutch is small. The reduction results in slipping and burning of the power disconnect clutch. Therefore, in order to secure the area of the friction surface, it is conceivable that the power cutoff clutch is of a multi-plate type including a plurality of clutch plates and clutch disks. However, when the power cut-off clutch using the disc spring as the engaging means is a multi-plate type, the wear amount of the clutch disc due to a change with time increases with an increase in the number of clutches.
In order to ensure the engagement force of the clutch even if the clutch disc wears due to changes over time, it is necessary to make the initial setting of the disc spring when the clutch is engaged considerably displaced. Also, since the amount of disc spring displacement required to release the clutch increases in proportion to the number of clutches,
In the case of a multi-plate type clutch, a considerable amount of displacement is required for releasing the clutch. Therefore, in order to release the clutch by making the disc spring considerably displaced at the time of initial setting and further displacing it from this state, the displacement region of the disc spring approaches the excessive stress region,
Furthermore, the disc spring itself has a smaller diameter due to the smaller diameter of the clutch, which shows the characteristic that the load change with respect to the displacement amount becomes large, and the usable displacement area of the disc spring becomes narrow. Such an excessive stroke results in an excessive stress region, which causes loss of spring elasticity early due to repeated operations, resulting in slippage or burning due to a reduction in clutch engagement force.

Therefore, in the present invention, a power cut-off clutch having a disc spring as an engaging means is arranged radially inward of the turbine blade and the pump blade to reduce the axial dimension. Is sufficiently secured, the change in characteristics due to the reduction in the diameter of the disc spring accompanying the reduction in the radial dimension of the power cutoff clutch, that is, the decrease in the usable area due to the increase in the load change with respect to the displacement amount, and the power The required displacement of the disc spring increases due to the multi-disc type of the disengagement clutch, that is, it is necessary to secure the engagement force when the clutch disc is worn by the multi-disc type of the power disengagement clutch and to reliably release the clutch. Due to an increase in the amount of displacement of the disc spring, the disc spring enters the area of excessive stress due to a slight overstroke, which reduces the durability of the disc spring. The prevented, by preventing slipping or burning of power cut-off clutch by lowering the engaging force, and to realize a compact power transmission device.

[Means for solving problems]

In order to achieve the above object, the present invention provides means for engaging an input shaft, an output shaft, and a fluid coupling and a disc spring which are interposed in series in a power transmission flow between the input shaft and the output shaft. In the power transmission device including a power cut-off clutch, the fluid coupling has a case connected to the input shaft, a pump blade provided in the case, and the pump blade for performing power transmission through the fluid with the pump blade. And a turbine blade disposed opposite to the turbine blade, wherein the power cutoff clutch is disposed inside the case of the fluid coupling and radially inward of the turbine blade and the pump blade, and is connected to the turbine blade. A clutch drum formed with a spline, a clutch hub connected to the output shaft and formed with an outta spline, and the clutch The disc spring includes a plurality of clutch discs and clutch plates alternately arranged on the inner spline of the ram and the outer spline of the clutch hub and fitted by splines. While pressing and engaging the clutch, the outer periphery is displaced by axial displacement of the inner periphery to disengage the power cutoff clutch, and the case is axially displaced in the outer periphery due to axial displacement of the inner periphery of the disc spring. Is provided with a stopper means that comes into contact with the outer circumference of the disc spring before entering the excessive stress region of the disc spring.

[Operation and effect of the invention]

In the power transmission device of the present invention thus configured,
When the power cut-off clutch is released, the outer periphery of the disc spring is axially displaced in the clutch release direction by the axial displacement of the inner periphery of the disc spring, but the displacement of the outer periphery is caused by the stopper means provided in the case of the fluid coupling. It is directly limited to the range that does not enter the oversized area. As a result, the displacement of the disc spring does not reliably enter the excessive stress region, and deterioration of the disc spring due to a slight overstroke is prevented.

Therefore, according to the present invention, the disc spring having the characteristic that the load change with respect to the displacement amount becomes large due to the small diameter and the usable displacement region is narrowed is used as the engaging means of the multi-plate type power cut-off clutch, and the clutch disc is The initial setting of the disc spring when the clutch is engaged is considerably displaced so that the clutch engaging force can be secured even if it is worn, and even if the disc spring is largely displaced to release the clutch from this state, the disc spring is The displacement of is not over stressed area,
Therefore, the power cut-off clutch is a multi-plate type, the friction surface area is sufficiently secured, and it can be arranged inside the turbine blade and the pump blade in the radial direction to reduce the axial dimension. Can be obtained.

[Embodiment] A power transmission device of the present invention will be described with reference to FIGS. 1 to 6.

This vehicle transmission includes a power transmission device 1, a gear transmission 200 for four forward speeds and one reverse speed, a differential mechanism (not shown), and a transmission case 300 housing these.

The power transmission device 1 includes a fluid coupling or fluid coupling (hereinafter referred to as a coupling) 110, a power cutoff clutch (hereinafter referred to as a clutch) 130 of a power cutoff device provided inside thereof, and a coupling 110 according to the present embodiment. Then, release the clutch 130, the direct coupling clutch 10 provided in the engine (the right side in the figure, hereinafter referred to as the right side), the oil pump 170 provided between the input member and the output member of the coupling 110. And a servo mechanism 190 for engaging.

The coupling 110 is a front cover 111 connected to the input shaft 101 of the power transmission device 1 connected to the crankshaft of the engine via a drive plate 102, and an annular plate shape welded to the outer periphery of the front cover 111. Rear cover 110
A, a pump blade 113 provided around the inner wall surface of the rear cover 110A, a turbine blade 114 arranged to face the pump blade 113, and the turbine blade 114.
And a turbine shell 115 holding the. At the center of the front cover 111, the large diameter portion of the engine is a pilot boss 105 that fits into a pilot hole 104 provided at the center of the end surface of the input shaft 101, and the gear transmission 200 is a gear (The left side is called "Wagawa" below)
A central shaft 108 is formed as a drive shaft 106 and a disk plate holding shaft 107 for supporting the cover 177 of the oil pump 170 slidably in both directions of the rotary shaft is provided in the middle. A cylindrical portion 111C having a frictional engagement surface 111A parallel to the shaft is continuously provided on the outer peripheral portion of the inner wall of the front cover 111.

The clutch 130 has an inner spline 133 formed on the inner periphery thereof, and a hub-shaped portion 116 of the turbine shell 115 welded on the outer periphery thereof at the left end in the drawing. Further, the clutch drive plate 158B, which is an output member of the direct coupling clutch 10, is slidable. A centering guide sleeve 144 is press-fitted and fixed to the clutch drum 134, and a hub portion 135 spline-fitted to the output shaft 103 of the power transmission device 1 is provided at a position corresponding to the inner spline 133 of the clutch drum 134. Perimeter spline 136
And a clutch hub portion 137 formed with the hub portion 1
A clutch disc wheel 139 including a disc portion 138 connecting the clutch hub portion 137 with the clutch hub portion 137, a plurality of clutch plates 141 spline-fitted to the clutch drum 134 on the outer periphery, and a clutch hub portion 137 of the clutch disc wheel 139 on the inner periphery. Clutch plate 1 splined to
41 and clutch discs 143 alternately stacked.

The direct coupling clutch 10 comprises a friction engagement surface 111A formed on the inner peripheral surface of the front cover 111 and a friction engagement element 400 supported by the damper drive plate 158B. The damper drive plate 158B is provided with a friction engagement element on the outer circumference, is fixed to the oil pump body 170A on the inner circumference, and is equipped with the damper spring 157 held by the front damper plate 158C on the outer circumference side. The damper drive plate 158B supports the pressing force of the diaphragm spring 2 on its left side in the figure, and contacts the bearing race 161 of the thrust bearing 160 mounted on the front cover 111 on its right side to support the pressing force of the diaphragm spring 2. It is fixed so as to be orthogonal to the clutch drum 134.

The oil pump 170, which is an internal gear pump in this embodiment, is provided on the inner peripheral side of the clutch hub portion of the clutch disc wheel 139. This oil pump 170
The outer periphery is fixed to the oil pump cover 177, and the inner periphery has a tip small diameter portion 103 of the output shaft 103 of the power transmission device 1.
An oil pump body 170A, which was loosely fitted to B through an oil seal 175 and abutted on the disc portion 138 of the clutch disc wheel 139 via a thrust bearing 176, and an engine of the oil pump body 170A were provided in the crocodile. Internal gear 172 rotatably fitted in the gear room
And an external gear 171 spline-fitted to the tip of the central shaft 108 and an oil passage 103A formed at the center of the output shaft 103 to connect between the oil pump cover 177 and the front cover 111. The suction port 174.

The servo mechanism 190 of the clutch 130 is a connecting rod 19 connected to a clutch pedal provided in the driver's seat or a servo mechanism operated by automatic supply / discharge of intake pipe negative pressure or hydraulic pressure.
1, a pressing rod 192 rotated around a fulcrum 193 by the connecting rod 191, a bearing 195 attached to a flange 194 abutting the tip 192A of the pressing rod 192, and the bearing
It is a reinforcing plate of the oil seal 198 between the sliding sleeve 6 fitted inside the 195 and the rear cover 110A and the sliding sleeve 6, and the inner periphery through which the output shaft 103 is inserted is radially outward as shown in FIG. The support 5 which is folded back to form the claw 51 and has an annular shape, and the inner peripheral portion 23 of the support 5 has a sliding sleeve 6 as shown in FIG.
The right end 62 is locked by a pin 197a, has an annular plate as shown in FIG. 3, and has a plurality of slits 24 and arm portions radially outward from the hollow portion 21 through which the output shaft 103 is inserted. A diaphragm spring 2 which is a disc spring in which 25 is provided around and the claw 51 of the support 5 is locked to the tip end portion 26 of the arm portion 25;
The fixing member 4 fixed to the rear cover 110A, the pressure plate 197 engaged with the outer peripheral portion 22 of the diaphragm spring 2, the thrust bearing 198A, the bearing race 3 of the thrust bearing 198A, and the clutch 130 are pressed. And a pressing ring 199 for the operation, and constitutes an operation mechanism for manually or automatically releasing and sliding the clutch 130 (semi-clutch).

The fixing member 4 has an annular plate shape as shown in FIGS.
The tubular portion 41 is composed of a tubular portion 41 and a radial portion 42. The tubular portion 41 is an outer spline of the bearing race 3 formed at regular intervals.
An inner spline 43 that fits with 31 is formed on the inner circumference 46, and the radial direction portion 42 is formed with stopper portions 44 that are slightly raised in the axial direction at regular intervals. When the sliding sleeve 6 is axially displaced toward the engine side in order to release the clutch 130, the stopper portion 44 is designed so that the diaphragm spring 2 reverses and the outer peripheral side thereof is displaced toward the gear transmission side. In order to prevent the diaphragm spring 2 from being excessively displaced and the load being excessive as shown in FIG. 6, the displacement amount is controlled so that the diaphragm spring 2 is not displaced beyond the point A, It is possible to prevent the durability of the diaphragm spring 2 from being lowered due to the increase in stress.

The gear transmission 200 has a well-known structure, an output shaft 103 of the power transmission device 1 is an input shaft, an output shaft 201 arranged in parallel with the input shaft, and a dog clutch for switching between first speed and second speed. 202, a dog clutch 203 for switching between the third speed and the fourth speed, and a reverse gear not shown.

This power transmission device 1 operates as follows.

The servo mechanism 190 of the clutch 130 has a pressing rod 192 as a fulcrum 193 when the connecting rod 191 is operated manually or automatically in the leftward direction in the drawing.
Rotate counterclockwise to displace the sliding sleeve 6 in the engine direction via the bearing 195. As a result, the sliding sleeve 6 causes the center of the diaphragm spring 2 to bulge into the engine, and the outer periphery 22 of the diaphragm spring 2 is displaced leftward in the drawing. By this action, the pressing force acting on the clutch 130 disappears and the clutch 130 is released. In this state, power is cut off by the clutch 130, so that the gear transmission 200 can perform a gear shift operation.

When the pressing force of the connecting rod 191 to the left in the drawing is released manually or automatically, the sliding sleeve 6 is displaced to the left in the drawing by the restoring force of the diaphragm spring 2, and the pressing ring is moved.
In 199, the engine is pressed by the alligator and the clutch 130 is engaged,
The input shaft 101 and the output shaft 103 of the power transmission device 1 are coupled.
Connected via 110.

Thus, according to the power transmission device of the above embodiment,
It is possible to prevent deterioration of the diaphragm spring 2 having a small diameter due to repeated excessive deformation, and maintain a predetermined clutch engagement force for a long period of time. Therefore, by realizing such an operation, both the clutch 130 and the diaphragm spring 2 can be accommodated on the inner peripheral side of the fluid coupling, and the axial dimension of the entire device can be made compact.

Although one embodiment of the power transmission device of the present invention has been described above, the stopper means of the disc spring may be formed integrally with the fluid coupling case, or the inner wall of the fluid coupling case may be used.

Although the fluid coupling uses the fluid coupling, a torque converter or the like can be used. It goes without saying that it can be used for other transmissions.

[Brief description of drawings]

FIG. 1 is a sectional view of a vehicle transmission incorporating the power transmission device of the present invention, FIG. 2 is an enlarged view of a main part of a vehicle transmission incorporating the power transmission device of the present invention, and FIG. Is a front view of a main part of the power transmission device of the present invention, FIG. 4 is a front view of a fixing member of the power transmission device of the present invention, and FIG. 5 is a sectional view taken along line AA of the fixing member of the power transmission device of the present invention. FIG. 6 and FIG. 6 are graphs of characteristic curves of diaphragm springs. 1 ... Power transmission device, 2 ... Diaphragm spring (disc spring), 4 ... Fixing member, 6 ... Sliding sleeve, 44 ... Stopper part (stopper means), 10
1 …… Input shaft, 103 …… Output shaft, 110 …… Fluid coupling (fluid coupling), 130 …… Power cutoff clutch

Claims (2)

[Claims] Claims: 1. An input shaft, an output shaft, and a power cut-off clutch having a disc coupling and a fluid coupling which are interposed in series between the input shaft and the output shaft in a power transmission flow in series. In the power transmission device described above, the fluid coupling is arranged to face the pump blade in order to transmit power through a case connected to the input shaft, a pump blade provided in the case, and the pump blade and fluid. And a turbine blade, wherein the power cutoff clutch is disposed inside the case of the fluid coupling and radially inward of the turbine blade and the pump blade, and is connected to the turbine blade to form a clutch drum. A clutch hub connected to the output shaft and having an outer spline, and an inner ply of the clutch drum. And a plurality of clutch discs and clutch plates alternately arranged on the outer splines of the clutch hub and spline-fitted, and the disc spring presses the power cut-off clutch by the spring load of the disc spring. While engaging, the outer periphery is displaced by the axial displacement of the inner periphery to disengage the power cutoff clutch, and the axial displacement of the outer periphery due to the axial displacement of the inner periphery of the disc spring in the case is A power transmission device comprising stopper means for contacting the outer periphery of the disc spring before entering the excessive stress region. 2. The power transmission device according to claim 1, wherein the stopper means is formed on a fixing member attached to the case.