JPH0221037A - Driving force transmission gear - Google Patents

Abstract

PURPOSE:To prevent vibration and echoing sounds from being generated in a driving force transmission gear for use in four-wheel drive and reduce disturbance which arises during ABS control, by interposing an one-direction rotation clutch which only transmits rotation in one direction between a rotating member and an axis of rotation. CONSTITUTION:A driving force transmission gear 20 is disposed between two shafts 15, 16 which are rotatable relatively of each other. A housing 21 is integrally coupled at its end to one 15 of the two shafts. An axis 22 of rotation rotatably supported by the housing 21 is coupled with the other shaft 16. An one-direction rotating clutch 50 which only transmits rotation in one direction is interposed between a rotating member 41 and the axis 22 of rotation. The rotating member is put in relative rotation on the axis 22 of rotation by the one-direction rotating clutch 50 during transmittance of inversed-torque so as not to generate pressure within a space 40 nor engage clutch means 25 therewith. Vibration and echoing sounds can thus be prevented from being generated therein and also disturbance which arises during ABS control can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a driving force transmission device that is disposed between two relatively rotatable shafts and transmits driving force between the two shafts.

<Prior art> The required function of a driving force transmission device for four-wheel drive is, of course, to transmit drive torque according to the differential between the front and rear wheels, but also to transmit the circulating torque peculiar to four-wheel drive. The purpose of this system is to absorb vibrations and prevent vibrations and muffled noise caused by the difference in rotational phase between the front and rear wheels during driving, as well as to reduce disturbances during ABS (anti-lock braking system) control.

<Problem to be solved by the invention> However, in conventional general driving force transmission devices,
The problem is that the same transmission characteristics are obtained both during positive torque transmission, which increases the rotation of the driving wheels, and when reverse torque transmission, which increases the rotation of the non-driving wheels, making it impossible to effectively absorb the above-mentioned circulating torque. was there.

For this reason, when transmitting positive torque, it is necessary to transmit sufficient torque between the front and rear wheels, but when transmitting reverse torque, on the other hand, it is desirable to develop an effective means to limit the transmitted torque. It was rare.

<Means for Solving the Problems> The present invention has been made focusing on the above-mentioned points, and includes a clutch means disposed between two relatively rotatable shafts and transmitting driving force between the two wheels. In the driving force transmission device, a housing is connected to one of the two shafts, a rotating shaft rotatably supported by the housing is connected to the other, a piston for pressing the clutch means is housed in the housing, and the A space is provided on the side of the piston, a high viscosity fluid is sealed in this space, and the high viscosity fluid is moved into the space by the differential rotation of the two axes, and the viscous friction causes the two axes to move. A rotating member equipped with blades that generate pressure according to differential rotation is housed, and a one-way rotation clutch that transmits rotation in only one direction is interposed between the rotating member and the rotating shaft.

With the above configuration, when positive torque is transmitted, the high viscosity fluid is forcibly moved between the two opposing surfaces by the rotating member, and the viscous friction generates pressure in the space according to the differential rotation. do. This pressure presses the piston, engages the clutch means, and transmits torque between the two shafts.

However, during reverse torque transmission, the rotating member is relatively rotated on the rotating shaft by the one-way rotation clutch due to the viscous resistance of the high viscosity fluid, so no pressure is generated in the space and the clutch means is not engaged.

<Example> Embodiments of the present invention will be described below based on the drawings.

FIG. 1 shows a driving force transmitting device 20 disposed between two relatively rotatable axles (front and rear wheel axles or left and right wheel axles) 15 and 16, and this driving force transmitting device 20 includes a housing 21,
A rotating shaft 22 that extends vertically through the housing 21 and is rotatably supported; a pressure generating section 23 that generates pressure according to the differential rotation between the housing 21 and the rotating shaft 22; It is mainly composed of a piston 24 to which the pressure generated by the piston 24 is applied, and a clutch means 25 that is frictionally engaged by the pressing force of the piston 24.

One end of the housing 21 is integrally connected to one 15 of the two shafts, and the other one 16 of the two shafts is splined into the rotating shaft 22. housing 2
1 has a bottomed cylindrical hollow hole 26 formed at one end thereof, and the piston 24 is slidably housed in the bottom surface of the hollow hole 26 with a predetermined gap, and the piston 24 is inserted into the housing 21. Rotation is prevented by engagement with a spline formed on the inner periphery of the shaft.

A cylindrical space 40 with a limited width in the axial direction is formed between the bottom wall of the housing 21 and the end wall of the piston 24. A rotating member 41 is housed in a slidable manner. As shown in FIG. 2, the rotating member 41 has a center portion fitted to the outer periphery of the rotating shaft 22 via a one-way rotating clutch 50 that allows rotation in only one direction, and two plates extending in the diametrical direction. It has a blade 42 of. As a result, the space 40 is circumferentially divided into a plurality of pressure chambers 43 by a plurality of blades 42, and each of these pressure chambers 43 is filled with a high viscosity fluid 44 such as silicone oil. Therefore, the rotating member 41 accommodated in the cylindrical space 40 described above
The pressure generating section 23 is composed of the high viscosity fluid 44 and the high viscosity fluid 44 .

When the two shafts 15.degree. 16 are rotated relative to each other by the pressure generating section 23 and the rotating member 41 is relatively rotated within the housing 21, the high viscosity fluid 44 filled in the pressure chamber 43 is released.
When the rotating member is forcibly moved by the blade 42 between the two opposing surfaces at a flow rate corresponding to the difference in rotational speed, the rotating member is moved inside the pressure chamber 43 due to viscous friction with both wall surfaces of the bottom surface of the housing 21 and the end surface of the piston 24. An internal pressure proportional to the rotational speed of 41 is generated. That is, this internal pressure is such that, for example, when the blade 42 rotates relative to the housing 21 in the direction of the arrow (hereinafter referred to as positive torque transmission), a pressure proportional to the relative rotational speed of the blade 42 is generated in the pressure chamber 43. Occur.

However, when the blade 42 rotates relative to the housing 21 in the direction opposite to the arrow shown in FIG. As a result, the high viscosity fluid 44 is rotated relative to the rotating shaft 22.
does not substantially move within the housing 21, and no pressure is generated within the pressure chamber 43.

An end cover 28 is attached to the open end of the hollow chamber 26 of the housing 21, and a sealed lubricating oil chamber 27 is formed between the end cover 28 and the piston 24, and the lubricating oil chamber 27 is filled with lubricating oil. is included. Inside the lubricating oil chamber 27, a plurality of outer plates 37 and inner plates 38 constituting the clutch means 25 consisting of a multi-plate clutch are arranged alternately, and the outer plates 37 are spline engaged with the inner periphery of the housing 21. The inner plate 38 is splined to a clutch hub 39 attached to the outer periphery of the rotating shaft 22.

Next, the operation of the driving force transmission device with the above configuration will be explained.

During positive torque transmission in which the rotating member 41 rotates relative to the housing 21, for example in the direction of the arrow in FIG. is forced to move between the two opposing surfaces at a flow rate according to the relative rotational speed difference, and due to the viscous friction of the high viscosity fluid 44, two shafts 1
An internal pressure proportional to the differential rotation of 5.16 is generated and the piston 24 is pressed.

Therefore, the plurality of outer plates 37 and inner plates 37 are frictionally engaged with each other with a pressing force corresponding to the pressure acting on the piston 24, and rotational torque is transmitted between the two shafts 15 and 16 via the clutch means 25.

That is, the transmitted torque for differential rotation is as shown by the solid line in FIG.

However, during reverse torque transmission in which the rotating member 41 rotates relative to the housing 21 in the direction opposite to the arrow in FIG. It is rotated relative to the shaft 22, no pressure is generated in the pressure chamber 43, and the clutch means 25 is not engaged.

In the embodiment described above, torque is not transmitted by the one-way clutch 50 during reverse differential rotation, but an example will be described below in which the transmitted torque is lower during reverse torque transmission than when normal torque is transmitted.

In FIG. 4, there are two pistons 2 in the housing 21.
4A and 24B are stored in series, and these two pistons 24
Spaces 40A and 40B filled with a high viscosity fluid and having different volumes M (effective diameters) are formed between pistons A and 24B and the other piston 24B and the housing bottom surface 21A. rotating member 41
A and 41B are housed in a slidable manner. These rotating members 41A and 41B are a one-way rotating clutch 50A that allows rotation only in mutually different directions.

It is mounted on the rotating shaft 22 via 50B. In addition, 60 in the figure is a rotation stopper that prevents the other piston 24B from rotating to the housing 21.

With the above configuration, when transmitting positive torque, the negative rotating member 41A is rotated relative to the housing 21, and pressure is generated in the space 40A due to the viscous friction of the high viscosity fluid 44, causing the pistons 24A and 24B to move. The clutch means 25 is engaged through the clutch means 25, and torque is transmitted between the two shafts 15 and 16.

On the other hand, during reverse torque transmission, the other rotating member 41B is rotated relative to the housing 21, and the high viscosity fluid 44
Pressure is generated in the space 40B due to the viscous friction of
Clutch means 25 via pistons 24B and 24A
is engaged. However, in this case, for example, the space 40B
By setting the capacity of the space portion 40A to be smaller than that of the space portion 40A, a difference is brought about in the viscous friction action of the high-viscosity fluid 44 when transmitting a forward torque and when transmitting a reverse torque, and when transmitting a reverse torque, the transmitted torque is is changed as shown by the broken line in FIG.

<Effects of the Invention> As described above, the present invention has a configuration in which a one-way rotating clutch that transmits rotation in only one direction is interposed between a rotating member and a rotating shaft, so when reverse torque is transmitted, high viscosity Due to the viscous resistance of the fluid, the rotating member is relatively rotated on the rotating shaft by the one-way rotation clutch, no pressure is generated in the space, and the clutch means is not engaged. This has the advantage that internal circulation torque can be absorbed, vibrations and muffled noise caused by the difference in rotational phase between the front and rear wheels during driving can be prevented, and disturbances during ABS control can be reduced.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a cross-sectional view of a driving force transmission device, FIG. 2 is a cross-sectional view taken along the line n-■ in FIG. 1, and FIG. 3 is a transmission torque characteristic with respect to differential rotation. FIG. 4 is a cross-sectional view of main parts showing another embodiment of the present invention. 21... Housing, 22... Rotating shaft, 24...
Piston, 25... Clutch means, 40... Space, 41... Rotating member, 42... Blade, 50...
・One-way rotation clutch.

Claims (1)

[Claims] (1) In a driving force transmission device equipped with a clutch means disposed between two relatively rotatable shafts and transmitting driving force between the two shafts, a housing is connected to one of the two shafts, and the housing is connected to the other shaft. A rotating shaft rotatably supported on the housing is connected, a piston for pressing the clutch means is housed in the housing, a space is provided on the side of the piston, and a high viscosity fluid is sealed in the space. Further, a rotating member having a blade that moves a high viscosity fluid by differential rotation of the two axes and generates pressure according to the differential rotation of the two axes by the viscous friction is housed in the space, A driving force transmission device including a one-way rotation clutch that transmits rotation in only one direction between a rotating member and the rotating shaft.