JPH0575529U - Driving force transmission device - Google Patents

Abstract

(57) [Abstract] [Purpose] In a driving force transmission device including a friction clutch for transmitting torque between an inner and outer rotating member and a pressing force generating unit for generating a pressing force for pressing the friction clutch in accordance with differential rotation. A delay in response of the device due to backlash in the circumferential direction between the clutch plates and clutch discs constituting the friction clutch and each rotary member is prevented. [Structure] Flexible parts 16c, 17c are formed in the axial direction between the sliding contact surfaces 16a, 17a of the clutch plate 16 and the clutch disc 17 and the engaging claws 16b, 17b. The clutch plate 16 and the clutch disc 17 are made flexible in the axial direction based on 16c and 17c.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a driving force transmission device that is interposed between two rotary members that are coaxially supported to transmit torque between the both rotary members.

[0002]

[Prior Art]

 Such a driving force transmitting device is interposed between both rotating members which are coaxially supported with each other, and when the both rotating members rotate relative to each other, these rotating members are connected to each other so that torque can be transmitted to each other. It is roughly classified into one used as a connecting mechanism for driving the members and one used as a differential limiting mechanism for limiting the rotation difference between the both rotating members. The former coupling mechanism is mainly installed in one power transmission path in a real-time four-wheel drive vehicle, and the latter differential limiting mechanism is mainly installed in each differential in the vehicle.

As a typical example of a conventional driving force transmission device is disclosed in Japanese Patent Laid-Open No. 63-240429, the driving force transmission device is provided between both inner and outer rotating members that are coaxially and relatively rotatable. A friction clutch that is actuated by relative rotation of both rotary members to generate a frictional engagement force that connects the two rotary members in a torque transmittable manner, and that increases or decreases the frictional engagement force according to the axial pressing force applied; There is a driving force transmission device provided with a pressing force generating means for generating a pressing force in the axial direction according to the relative rotation of the both rotating members and applying the pressing force to the friction clutch. Thus, the friction clutch generally has a plurality of clutch plates having a plurality of engaging claws that engage with the inner spline grooves of the outer rotating member on the outer peripheral edge of the sliding surface, and the outer clutch of the inner rotating member. It is composed of a plurality of clutch discs having a plurality of engaging claws that engage with the line grooves on the inner peripheral edge of the sliding contact surface.

In this type of driving force transmission device, when relative rotation occurs between both rotary members, pressure corresponding to the differential rotation speed is generated in the pressing force generation means, and this pressure presses the friction clutch. A frictional engagement force that connects both rotating members to the same clutch so that torque can be transmitted is generated. Such frictional engagement force is proportional to the differential rotation speed, and torque proportional to the differential rotation speed is transmitted from one to the other between the two rotary members. Therefore, the driving force transmission device functions as a connecting mechanism between the driving side rotation member and the driven side rotation member in one power transmission system path of the four-wheel drive vehicle, and also between the driving side and the driven side rotation member and both driving sides. It also functions as a differential limiting mechanism between the rotating members or between both driven side rotating members.

[0005]

[Problems to be solved by the device]

 By the way, functionally, each clutch plate and each clutch disk constituting the above-mentioned friction clutch needs to move in the axial direction when a pressing force is applied and when the pressing force is released thereafter. In some cases, the frictional torque depending on the pressing force of the friction clutch may not be accurately obtained due to the sliding resistance. In addition, since the circumferential clearance, that is, the play is secured when the engagement claws of the clutch plate and the clutch disc and the spline groove are fitted to each other, the play is relatively prevented between the rotating members. This causes a delay in the operation of the friction clutch when rotation occurs, which is one of the causes of reducing the responsiveness of the device. Therefore, an object of the present invention is to address such a problem.

[0006]

[Means for Solving the Problems]

 According to the present invention, in the driving force transmission device of the above-mentioned type, the sliding contact surface of at least one of the clutch plate and the clutch disc constituting the friction clutch and the engaging claw are formed in an axially flexible region. It is characterized by being formed.

[0007]

[Operation and effect of the device]

 In the driving force transmission device having such a configuration, at least one of the clutch plate and the clutch disc forming the friction clutch is provided with a flexible portion axially flexible between the sliding contact surface and the engaging claw. , When the pressing force is applied, the sliding contact surface moves in the axial direction with the flexible part as the base point without the engaging claw moving in the axial direction, and the sliding contact surface between the clutch plate and the clutch disc rubs against each other. Engage. Therefore, in the friction clutch, it is not necessary to secure a backlash between the engagement claws of the clutch plate and the clutch disc and the spline groove in a fitted state, and the operation delay of the device caused by the backlash is not necessary. Therefore, the responsiveness of the device can be improved.

[0008]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment of a driving force transmission device according to the present invention. As shown in FIG. 7, the driving force transmission device 10 is arranged in a rear wheel side power transmission system path of a real-time type four-wheel drive vehicle. The vehicle is always driven by the front wheels and driven by the rear wheels when necessary. The transaxle 22 mounted on one side of the engine 21 has a transmission and a transfer gear, and outputs the power from the engine 21 to the axle shaft 23. Then, the front wheels 24 are driven and output to the first propeller shaft 25. The first propeller shaft 25 is connected to the second propeller shaft 26 via the driving force transmission device 10, and when both the shafts 25, 26 can transmit torque, power is transmitted to the axle shaft 28 via the rear differential 27. It is output and the rear wheels 29 are driven.

The driving force transmission device 10 includes an outer case 11 and an end cover 12 which are outer rotating members, and a pressing force generating means 10 a and a friction clutch 10 b in an annular working chamber which is composed of an inner shaft 13 which is an inner rotating member. There is. The outer case 11 is provided with an inward flange portion 11b at one end of a tubular portion 11a having a predetermined length, and an end cover 12 is screwed into the other end opening portion of the tubular portion 11a. The inner shaft 13 is provided with an outward flange portion 13b on the outer periphery of the middle portion of a stepped cylindrical portion 13a having a predetermined length, an outer spline portion 13c extending in the axial direction is formed on the outer periphery of the flange portion 13b, and the cylindrical portion 13a is formed. An inner spline portion 13d extending in the axial direction is formed on the inner periphery of one end side of the. In the inner shaft 13, one end of the tubular portion 13a is fitted in the inner hole of the inward flange portion 11b of the outer case 11 and the other end is fitted in a liquid tight and rotatable manner in the inner hole of the end cover 12. Has been supported. The inner shaft 13 is fitted and fixed to the spline at the tip of the second propeller shaft 26 at the inner spline portion 13d, and the outer case 11 is fixed to the rear end of the first propeller shaft 25.

The pressing force generating means 10 a includes an operating piston 14 and a rotor 15, and the friction clutch 10 b is of a wet multi-plate clutch type and includes a large number of clutch plates 16 and clutch discs 17. As will be described later, each clutch plate 16 has an engaging claw on the outer periphery thereof fitted into a spline groove of a spline portion 11c provided on the inner periphery of the outer case 11 so as to be integrally rotatably assembled to the same. There is. Each clutch disk 17 has its inner engaging claws fitted in the spline groove of the outer spline portion 13c of the inner shaft 13 so as to be located between the clutch plates 16 and assembled to the shaft 13 so as to be integrally rotatable. Has been. A predetermined amount of clutch oil and gas is enclosed in the accommodation chamber of the clutch plate 16 and the clutch disc 17.

The actuating piston 14 that constitutes the pressing force generating means 10 a is liquid-tightly integrally rotatable with the inner circumference of the other end side of the tubular portion 11 a of the outer case 11 and slidable in the axial direction. On the other hand, they are mounted on the outer periphery thereof in a liquid-tight manner so as to be rotatable in a liquid-tight manner and slidable in the axial direction. As shown in FIGS. 1 and 2, the rotor 15 is provided with two vane portions 15b extending in the radial direction at portions of the outer circumference of the annular boss portion 15a that are equally spaced apart from each other. The shaft 13 is fitted on the outer circumference of the cylindrical portion 13a and is integrally rotatably assembled to the shaft 13. The rotor 15 is formed to have a thickness substantially the same as the depth of the annular recess 14a provided on one side of the working piston 14, and is fitted in the annular recess 14a. The end cover 12 is liquid-tightly fitted to the outer periphery of the other end side of the tubular portion 13a of the inner shaft 13 so as to be slidable in the axial direction and rotatably, and is screwed to the outer case 11 so as to be movable back and forth. , And is liquid-tight. The end cover 12 is axially adjusted in position and fixed to the outer case 11 by caulking means. One side of the end cover 12 comes into contact with the other side of the working piston 14 so that the rotor 15 is positioned by the working piston 14. It forms a fluid chamber that A predetermined amount of highly viscous fluid such as silicone oil and air are enclosed in this fluid chamber, and the rotor 15 fluid-tightly contacts the outer periphery of its vane portion 15b with the inner periphery of the annular recess 14a. The room is divided into two retention chambers R.

As shown in FIGS. 3 to 5, the clutch plate 16 that constitutes the friction clutch 10b is provided with a plurality of engaging claws 16b on the outer peripheral edge of the ring-shaped sliding contact surface 16a. Further, the clutch disc 17 is provided with a plurality of engaging claws 17b on the inner circumference of a ring-shaped sliding contact surface 17a. In both of these, recesses are formed on both surfaces between the sliding contact surfaces 16a, 17a and the engaging claws 16b, 17b, and the both are constituted by flexible portions 16c, 17c which are thin in the axial direction. ing. The flexible portions 16c and 17c exhibit flexibility in the axial direction. The sliding surface 17a of the clutch disc 17 is made of friction paper.

In the driving force transmission device 10 having such a configuration, torque is transmitted when relative rotation occurs between the first and second propeller shafts 25 and 26. That is, when the shafts 25 and 26 rotate relative to each other, the outer case 11, the end cover 12, the operating piston 14, and the second propeller shaft 26, which are integrally rotatable with the first propeller shaft 25, are assembled. Relative rotation occurs between the inner shaft 13 and the rotor 15 which are integrally rotatably mounted on the rotor. Therefore, in the fluid chamber of the pressing force generating means 10a, the viscous fluid in the retention chamber R is forcibly flown at a speed proportional to the relative rotation speed, and in the retention chamber R sequentially moving in the circumferential direction. Due to the flow resistance, a pressure distribution in which the pressure is gradually increased from the downstream end of the vane portion 15b toward the upstream end of the next vane portion 15b is generated. The pressure increasing portion of this pressure distribution increases in proportion to the differential rotation speed and presses the working piston 14 in the axial direction. As a result, the working piston 14 presses the friction clutch 10b to frictionally engage the clutch plates 16 and the clutch disc 17 with each other via the clutch oil. As a result, in the friction clutch 10b, torque proportional to the differential rotation speed is transmitted from the outer case 11 to the inner shaft 13, and the vehicle is in the four-wheel drive state. Further, in this four-wheel drive state, differential rotation of the front and rear wheels is allowed, and the occurrence of the tight corner braking phenomenon is prevented.

By the way, in the driving force transmission device, the clutch plate 16 and the clutch disc 17 which constitute the friction clutch 10b are flexible in the axial direction between the sliding contact surfaces 16a, 17a and the engaging claws 16b, 17b. The flexible parts 16c, 17c are provided, and when the pressing force is applied, the respective engaging claws 16b, 17b do not move in the axial direction. The sliding contact surfaces 16a, 17a move the flexible parts 16c, 17c. The clutch plate 16 and the clutch disc 17 are frictionally engaged with each other by sliding in the axial direction as a base point. Therefore, in the friction clutch 10b, it is not necessary to secure a backlash between the engaging claws 16b and 17b of the clutch plate 16 and the clutch disc 17 and the respective spline grooves in a fitted state, and the backlash is not generated. It is possible to eliminate the delay in the operation of the device due to it and improve the responsiveness of the device.

FIG. 6 shows a main part of a modified example of the clutch plate that constitutes the friction clutch. In the clutch plate 18, two slit-shaped recesses are formed on the circumferential side between the sliding contact surface 18a and the engaging claws 18b, and a flexible portion 18c is formed between the two recesses. There is. The flexible portion 18c has a small width in the circumferential direction and exhibits flexibility in the axial direction. Therefore, even if the clutch plate 18 is adopted as the friction clutch, the same operational effect as that of the embodiment can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view of a driving force transmission device according to an embodiment of the present invention.

FIG. 2 is a front view of a rotor that constitutes the same device.

FIG. 3 is a front view of a clutch plate and a clutch disc of the friction clutch that constitute the same device.

FIG. 4 is an enlarged partial front view (a) and a vertical side view (b) of the clutch plate.

FIG. 5 is an enlarged partial front view (a) and a vertical side view (b) of the clutch disc.

FIG. 6 is an enlarged partial front view showing a modified example of the clutch plate.

FIG. 7 is a schematic configuration diagram of a vehicle that employs the device.

[Explanation of symbols]

10 ... Driving force transmission device, 10a ... Pressing force generating means, 10
b ... Friction clutch, 11 ... Outer case, 12 ... End cover, 13 ... Inner shaft, 14 ... Working piston,
15 ... Rotor, 15b ... Vane part, 16, 18 ... Clutch plate, 17 ... Clutch disc, 16a, 17
a, 18a ... Sliding contact surface, 16b, 17b, 18b ... Engaging claws, 16c, 17c, 18c ... Flexible parts, 25, 26
… Propeller shaft, R… Retention chamber (fluid chamber).

Claims (1)

[Scope of utility model registration request] 1. A frictional engagement force which is provided between both inner and outer rotary members coaxially and relatively rotatably positioned and which is actuated by relative rotation of the two rotary members to connect the two rotary members in a torque-transmittable manner. A friction clutch that increases or decreases the frictional engagement force according to the axial pressing force that is applied together with the friction clutch, and an axial pressing force that is generated according to the relative rotation of the rotary members to generate the pressing force on the friction clutch. A plurality of clutch plates having a pressing force generating means for applying the friction clutch, the clutch plates having a plurality of engaging claws for engaging the friction clutch with the inner spline groove of the outer rotating member, and the inner rotating member; In the driving force transmission device, the friction clutch is constituted by a plurality of clutch discs having a plurality of engaging claws engaging with the outer spline groove of the inner peripheral edge portion of the sliding contact surface. Driving force transmission device, characterized in that formed on the flexible portion of the flexible axially between at least one of the sliding contact surface and the engaging claws of the clutch plate and clutch disc are formed.