JPH0348028A - Driving force transmission device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a driving force transmitting device which is disposed between both inner and outer rotating members that are coaxially and relatively rotatably located, and which transmits torque between these two members. Regarding equipment.

(Prior Art) Such a driving force transmission device is disposed between a driving side rotating member and a driven side rotating member, and connects these two members so that torque can be transmitted to each other when these two members rotate relative to each other, so that the driven side rotation A connecting mechanism that is used as a coupling mechanism to drive members, and a mechanism that is disposed between a driving side and a driven side rotating member, between a re-driving side rotating member, or between both driven side rotating members, and when these two members rotate relative to each other. These two members are broadly classified into those used as differential limiting mechanisms that limit the rotational difference between these two members by connecting them to each other so as to transmit torque. The former coupling mechanism is mainly disposed on one power transmission path in a real-time four-wheel drive vehicle, and the latter differential limiting mechanism is mainly disposed on each differential in the vehicle.

However, as a conventional driving force transmission device,
As shown in Japanese Patent No. 240429, it is disposed between both inner and outer rotating members that are coaxially and relatively rotatably positioned,
a friction clutch that is actuated by the relative rotation of these two rotating members to generate a frictional engagement force that connects the two rotational members so that torque can be transmitted, and that increases or decreases the frictional engagement force in accordance with the applied axial pressing force; A pressing force generating means is provided for generating an axial pressing force corresponding to the relative rotation of the two rotating members and applying it to the friction clutch, and the pressing force generating means is arranged between the two rotating members in a fluid-tight manner in the axial direction. A shaft is provided between an actuating piston that is slidably attached to the outer rotating member and is integrally rotatable with the outer rotating member and faces the friction clutch, and an actuating piston that is integrally or integrally rotatably provided with the outer rotating member. a retainer forming a fluid chamber in which a viscous fluid is sealed at a predetermined interval in the direction; and one or more vanes extending in the radial direction, the retainer being integrally assembled to the inner rotating member in the fluid chamber. There is a driving force transmission device configured with a rotor.

In this type of driving force transmission device, when relative rotation occurs between both rotating members, an actuating piston and a retainer are assembled to be integrally rotatable with the outer rotating member, and a rotor is integrally assembled with the inner rotating member. During this period, relative rotation occurs, and the viscous fluid within the enclosure chamber is forced to flow by the vane portion of the rotor in the fluid chamber, and pressure is generated within the enclosure chamber due to flow resistance or the like. That is, a pressure corresponding to the differential rotation speed is generated in the pressing force generating means. This pressure pushes the actuating piston in the axial direction, causing the friction clutch to be pressed and generating a frictional engagement force in the clutch that connects both rotating members in a torque-transmitting manner. This frictional engagement force is proportional to the differential rotation speed, and a torque proportional to the differential rotation speed is transmitted between the two rotating members from one side to the other. Therefore, the driving force transmission device functions as a coupling mechanism between the driving side rotating member and the driven side rotating member in one power transmission path of the four-wheel drive vehicle, and also functions as a connection mechanism between the driving side rotating member and the driven side rotating member. It also functions as a differential limiting mechanism between rotating members or between both driven rotating members.

(Problem to be Solved by the Invention) By the way, in a four-wheel drive vehicle that employs the above-mentioned type of drive force transmission device as a coupling mechanism for a power transmission path, it is difficult to tow the vehicle with one of the front and rear wheels fixed. When transporting the vehicle, a large differential rotation occurs for a long period of time between both rotating members of the driving force transmission device, and the friction clutch is in frictional sliding contact for a long period of time under a large frictional engagement force. For this reason, seizure and other types of burnout occur in friction clasps.

It is therefore an object of the present invention to address such problems.

(Means for Solving the Problems) The present invention provides a driving force transmission device of the above type, in which:
The outer rotating member is characterized in that the outer rotating member is provided with an operation regulating member that faces between the operating piston and the friction clutch from outside the outer rotating member and comes into contact with and separates from the operating piston when rotated from the outside.

(Operations and Effects of the Invention) According to this configuration, the normal operation regulating member is spaced apart from the operating piston, so that the operating piston is not restricted in the axial direction by the operation regulating member and can perform its original pressing force. It functions to press the friction clutch and generate a frictional engagement force that connects both rotating members to the clutch so that torque can be transmitted in accordance with the operating rotational speed.

On the other hand, when transporting a vehicle equipped with the drive force transmission device by towing with one of the front and rear wheels fixed, the operation regulating member must be rotated from the outside before the operation piston is moved. Bring it into contact. As a result, the actuating piston is restricted in the axial direction by the actuation restricting member, and its pressing function against the friction clutch is disabled. As a result, even if a large differential rotation occurs between the two rotating members and continues for a long time, the friction clutch will not come into frictional sliding contact under a large frictional engagement force, and the clutch will not seize or suffer other damage. It will never occur.

(Example) Examples of the present invention will be described below based on the drawings.
The figure shows an embodiment of the driving force transmission device according to the present invention. As shown in FIG. 5, the driving force transmission device 10 is disposed in a rear wheel power transmission path of a real-time four-wheel drive vehicle.

In this vehicle, the front wheels are always driven and the rear wheels are driven when necessary. A transaxle 22 attached to one side of the engine 21 is equipped with a transmission and a transfer, and outputs the driving force from the engine 21 to an axle shaft 23. The power is output to the first propeller shaft 25 and drives the front wheels 24 . The first propeller shaft 25 is connected to a second propeller shaft 26 via the drive power transmission device 10, and these two shafts 25.2
6 is capable of transmitting torque, the driving force is output to the axle shaft 28 via the rear differential 27, and the rear wheels 29 are driven.

Thus, the driving force transmission device 10 includes a pressing force generating means 10a and a friction clutch 10b in an annular working chamber made up of an outer case 11 and an inner shaft 12.

The outer case 11 includes an inward flange portion 11b at one end of a cylindrical portion 11a having a predetermined length, the other end of the cylindrical portion 11a is open, and a threaded portion 11c is formed on the inner periphery of the other end. The inner shaft 12 has a stepped cylindrical portion 12 with a predetermined length.
An outward flange portion 12b is provided on the outer periphery of the intermediate portion of a,
An outer spline portion 12C extending in the axial direction is formed on the outer periphery of the flange portion 12b, and an inner spline portion 12d extending in the axial direction is formed on the inner periphery on one end side of the cylindrical portion 12a. In such an inner shaft 12, the cylindrical portion 1
One end of 2a is the inward flange portion 11b of the outer case 11.
A pressing force generating means 1, which will be described later, is fluid-tightly and rotatably fitted into the inner hole of the cylinder part 12a, and is assembled to the outer periphery of the other end of the cylindrical part 12a.
It is rotatably supported by the outer case 11 via the component 0a. The inner shaft 12 is fixed at its inner spline portion 12 d by fitting into the spline 26 a at the tip of the second propeller shaft 26 , and the outer case 11 is fixed to the rear end of the first propeller shaft 25 .

The pressing force generating means 10a includes an operating piston 13 and a rotor 14.
and a retainer 15, and a friction clutch 10b
The clutch is of a wet type multi-plate clutch type and consists of a large number of clutch plates 16 and clutch discs 17. Each clutch plate 16 has a spline portion on its outer periphery fitted into a spline portion lid provided on the inner periphery of the outer case 11, and is assembled to the case 11 so as to be integrally rotatable and movable in the axial direction. Each clutch disk 17 has a spline portion on its inner circumference fitted into an outer spline portion 12c of the inner shaft 12, is located between each clutch plate 16, and is assembled to the shaft 12 so as to be rotatable and movable in the axial direction. It is being

A predetermined amount of clutch oil and gas are sealed in the storage chamber R1 of the clutch plate 16 and the clutch disc 17.

The actuating piston 13 constituting the pressing force generating means 10a is rotatable integrally with the inner periphery of the other end side of the cylindrical portion 11a of the outer case 11, and is slidable in the axial direction in a fluid-tight manner, and with respect to the inner shaft 12. They are respectively attached to the outer periphery thereof in a liquid-tight manner so as to be rotatable and slidable in the axial direction, and their negative side surface 13a abuts against the clutch plate 16 at the rightmost end in the figure.

As shown in FIGS. 1 and 2, the rotor 14 includes two vane portions 14b extending in the radial direction at positions 180° apart from each other on the outer periphery of the annular boss portion 14a. It is integrally assembled to the outer periphery of the cylindrical portion 12a of the inner shaft 12. The rotor 14 is formed to have approximately the same thickness as the depth of the annular recess 13b provided on the other side of the actuating piston 13, and is fitted into the annular recess 13b. The retainer 15 has a threaded portion 15a on the outer periphery of the other end, and is fitted to the outer periphery of the other end of the cylindrical portion 12a of the inner shaft 12 so as to be slidable and rotatable in the axial direction in a fluid-tight manner, and is connected to the outer case 11. The threaded portion 15a is screwed into the threaded portion 11c of the outer case 11 so that it can move forward and backward, and is liquid-tight.

In this retainer 15, the position is adjusted in the axial direction and fixed to the outer case 11 by caulking means, and the - side surface 15b abuts the annular outer edge surface 13c on the other side of the operating piston 13, and the - side surface 15b and working piston 1
The annular recess 13b of No. 3 forms a fluid chamber in which the rotor 14 is located. A predetermined amount of highly viscous fluid such as silicone oil is sealed in this fluid chamber, and the rotor 14 has the outer periphery of its vane portion 14b in liquid-tight contact with the inner periphery of the annular recess 13b, and A minute gap is formed between both side surfaces, the other side surface 13b1 of the annular recess 13b, and one side surface 15b of the retainer 15, thereby dividing the fluid chamber into two retention chambers R2.

The cylindrical portion 11a of the outer case 11 is provided with an insertion hole 11e as shown in FIGS. 1 and 3, and the actuating piston 13 is provided with an insertion hole 11e as shown in FIGS.
Notch for insertion as shown in the picture? 1113d is provided, and the operation regulating rod 18 faces the cutout groove 13d through the insertion hole lie.The operation regulating rod 18 consists of a head 18a, a neck 18b and a leg 18c, and the neck 1
The screw portion 8b is rotatably screwed into the insertion hole 11e in a liquid-tight manner. Leg portion 18c of operation regulating rod 18
is provided with a flat portion 18d which is a partially cut out part of a cylinder having a predetermined diameter. Further, the notch groove 13d of the actuating piston 13 has a rectangular shape that opens toward the friction clutch 10b, and is formed to have the following size in relation to the operation regulating rod 18. That is, the operation regulating rod 18 can be rotated by an external rotation operation to move the flat portion 18d of the leg portion 18c toward the friction clutch 10b side and the actuating piston 13 side, but when the flat portion 18d is on the friction clutch 10b side. When the leg portion 18c is in contact with the bottom of the cutout groove 13d as shown in FIGS. 3 and 4(a), and the flat portion 18d is on the operating piston 13 side, the flat portion 18d is in contact with the bottom of the notch groove 13d as shown in FIG. 4(b). As shown in FIG. 2, it is formed in a size that is spaced apart from the bottom of the notch groove 13d.

In the driving force transmission bag W10 having such a configuration, the operation regulating rod 18 is normally in the state shown in FIG. 1. Both second propeller shafts 25.2
When relative rotation occurs between the two, torque is transmitted. That is, when relative rotation occurs between these two shafts 25 and 26, the outer case 11, operating piston 13, and retainer 15, which are assembled to be integrally rotatable with the first propeller shaft 25, and the second propeller shaft 26 are integrally rotated. Relative rotation occurs between the inner shaft 12 and the rotor 14, which are rotatably assembled. Therefore, in the fluid chamber of the pressing force generating means 10a, the viscous fluid in the retention chamber R2 is forced to flow at a speed proportional to the relative rotational speed, and the viscous fluid in the retention chamber R2 moves relative to each other in the circumferential direction. Due to the resistance, a pressure distribution is generated in which the pressure is gradually increased from the downstream end of the vane section 14b to the upstream end of the next vane section 14b. The pressure increasing portion of this pressure distribution increases in proportion to the differential rotation speed, and presses the actuating piston 13 in the axial direction. As a result, the actuating piston 13 presses the friction clutch 10b to frictionally engage each clutch plate 16 and clutch disk 17 that constitute the friction clutch 10b 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 12, and the vehicle enters a four-wheel drive state. Further, in this four-wheel drive state, differential rotation between the front and rear wheels is allowed, and the occurrence of tight corner braking is also prevented.

By the way, by rotating the operation regulating rod 18 from the outside, the flat portion 18d of the friction clutch 10brf! 4, the operation regulating rod 18 is moved to the position shown in FIGS. 3 and 4.
As shown in Figure (a), it comes into contact with the actuating piston 13 and restricts the piston 13 in the axial direction. For this reason, the actuating piston 13 is disabled from its pressing function against the friction clutch 10b, and the clutch 10b is
Even if relative rotation occurs between the two, there will be no frictional engagement. Therefore, when the operation regulating rod 18 is rotated as shown in FIGS. 3 and 4(a) in the event of an abnormality in which the vehicle is being indexed and transported with one of the front and rear wheels fixed,
The friction clutch 10b does not come into frictional sliding contact under a large frictional engagement force when the vehicle is indexed.
There will be no burning or other burnout.

In the above embodiment, a fluid chamber is formed between the actuating piston 13 and the retainer 15, and the rotor 14 is disposed in the fluid chamber.
The rotor 14 may be disposed in the fluid chamber formed between the inner wall of the retainer 1 and the working piston, and a friction clutch 10b may be disposed between the working piston and the retainer 15.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a driving force transmission device according to an embodiment of the present invention, FIG.
The figure is an enlarged cross-sectional view of the main part of the device, Figures 4 (a) and (b).
5 is an explanatory diagram of the operation of the operation regulating rod, and FIG. 5 is a schematic diagram of a vehicle employing the same device. Description of symbols 10... Drive force transmission device, 10a... Pressing force generating means, 10b... Friction clutch, 11... Outer case, lle... Insertion hole, 12... Inner shaft, 13
... Working piston, 13d... Notch groove, 14...
Rotor, 14b... Vane part, 15... Retainer, 1
6.Clutch plate, 17.Clutch disc,
18... Operation regulating rod, 18c... Leg part, 18d
...Plane part, 25.26...Propeller shaft.

Claims (1)

[Claims] It is disposed between the inner and outer rotating members that are coaxially and relatively rotatably positioned, and is actuated by the relative rotation of these rotating members to generate and apply a frictional engagement force that connects the two rotating members so that torque can be transmitted. A friction clutch that increases or decreases the friction engagement force in accordance with an axial pressing force, and a pressing force generating means that generates an axial pressing force in accordance with the relative rotation of both rotating members and applies it to the friction clutch, The pressing force generating means is configured to include an actuating piston that is slidable liquid-tightly in the axial direction between the two rotary members and integrally rotatable with the outer rotary member and faces the friction clutch; a retainer that is integrally or rotatably provided with the actuating piston and forms a fluid chamber in which a viscous fluid is sealed, having a predetermined spacing between the retainer and the actuating piston; and one or more vanes extending in the radial direction. a rotor that is integrally rotatably assembled to the inner rotating member in the fluid chamber, the drive force transmitting device comprising: a rotor that is integrally rotatably assembled to the inner rotating member in the fluid chamber; A driving force transmission device characterized in that the outer rotary member is provided with an operation regulating member that comes into contact with and separates from the actuating piston when rotated from the outside.