JPH02120530A - Driving force transmission - Google Patents

Abstract

PURPOSE:To make respective transmitting characteristics different in case of normal torque and reverse torque by providing a guide ring rotating with a blade in one body, and opening a pressure introducing port communicated to a pressure actuating chamber in the position corresponding to a high pressure territory of the pressure chamber on the guide ring. CONSTITUTION:At normal torque transmission, a pressure introducing port 49 opened on a guide ring 48 rotating in one body with a blade 42 is positioned in a high pressure territory, pressure introduced to a pressure actuating chamber 47 from this port 49 becomes high, and the thrust force acting on a piston 24 increases. On the contrary, at reverse torque transmission, as the port 49 opened on the guide ring 48 is positioned in a low pressure territory, pressure introduced to the pressure actuating chamber 47 from the port 49 is low, and the thrust force acting on the piston 24 decreases. Consequently, transmitting torque against differential rotation increases at normal torque transmission, on the contrary, transmitting torque against differential rotation decreases at reverse torque transmission.

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 objective is to absorb vibrations and prevent vibrations and muffled noise caused by the rotational phase difference between the front and rear wheels during driving, and 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.

By the way, as disclosed in Japanese Patent Application Laid-Open No. 63-240429, the pressure generated by viscous friction of the high viscosity fluid can be reduced by forcibly moving the high viscosity fluid sealed between two close surfaces using a blade. In a torque transmission device that transmits driving force by acting on a piston and connecting a multi-disc clutch with torque corresponding to differential rotation, the pressure distribution in the pressure generation part has a continuous pressure gradient in the rotation direction of the blade. , a thrust corresponding to the integrated value (average value) of the pressure acts on the piston.

<Means for Solving the Problems> Therefore, the present invention focuses on the pressure in the high pressure region and low pressure region of the pressure distribution described above, and brings about a difference between the forward torque transmission characteristic and the reverse torque transmission characteristic. The structure is such that 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 and a side plate that press the clutch means are housed in the housing, and the piston and the side plate are housed in the housing. A pressure acting chamber is formed between the side plate, a space is provided on the side of the side plate, a high viscosity fluid is sealed in this space, and a high viscosity fluid is filled in the space by the differential rotation of the two axes. A blade that moves a fluid and generates pressure according to the differential rotation of two axes by its viscous friction is housed, a guide ring that rotates integrally with the blade is provided, and the guide ring is communicated with the pressure acting chamber. A pressure introduction port is opened at a position corresponding to the high pressure region of the pressure chamber.

With the above configuration, when the two shafts rotate relative to each other, the high viscosity fluid in the space is forcibly moved between the two closely spaced surfaces by the blades, and the viscous friction of the high viscosity fluid increases the pressure according to the differential rotation. Occur.

In this case, during positive torque transmission, the pressure introduction port opened in the guide plate that rotates integrally with the flade is located in a high pressure region, and the pressure introduced from this pressure introduction port into the pressure action chamber increases, causing the piston The thrust acting on the is increased.

On the other hand, during reverse torque transmission, the pressure introduction port opened in the guide plate is located in the low pressure region, so the pressure introduced into the pressure action chamber is lower than the pressure introduction port, and the thrust acting on the piston is is reduced.

Therefore, during normal torque transmission, the transmission torque for differential rotation can be increased, and conversely, during reverse torque transmission, the transmission torque for differential rotation can be decreased.

<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) 1516, and this driving force transmitting device 20 includes a housing 21 and a housing 21
A rotating shaft 22 that extends longitudinally through the housing 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, and 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 pressure 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 shaft 16 of the two shafts is spline-engaged within the rotating shaft 22. A hollow cylindrical hole 26 with a bottom is formed in the housing 21 from one end thereof,
The piston 24 is slidably housed in the hollow hole 26, and the piston 24 is engaged with a spline formed on the inner circumference of the housing 21 to prevent rotation. Further, a side plate 27 is housed in the hollow hole 26, and the side plate 27 is prevented from rotating so that it can only slide relative to the piston 24.

A cylindrical space 40 is formed at the bottom of the hollow hole 26, and the open end of this space 40 is connected to the side plate 27.
is blocked by. A rotating member 41 having a thickness slightly smaller than its width is slidably accommodated in the space 40, that is, between the bottom surface of the hollow hole 26 and the end surface of the side plate 27. The center is the second
As shown in the figure, the rotary shaft 22 is secured to the outer periphery of the rotary shaft 22 by a spline. The rotating member 41 is composed of two blades 42 extending in the diametrical direction, and these blades 42 partition the space 40 into a plurality of pressure chambers 43 on the circumference. Each pressure chamber 43 is filled with a high viscosity fluid 44 such as silicone oil, and this high viscosity fluid 44 is forcibly moved by the blade 42, and due to its viscous friction action, the relative rotation of the blade 42 is caused within the pressure chamber 43. A corresponding pressure is generated. The pressure generating section 23 is constituted by the rotating member 41 and the high viscosity fluid 44 housed in the cylindrical space 40 described above.

An end cover 28 is attached to the open end of the hollow chamber 26 of the housing 21, and a sealed clutch chamber 36 is formed between the end cover 28 and the piston 24, and a lubricating oil is sealed in the clutch chamber 36. has been done. Inside the clutch chamber 36, a plurality of outer plates 37 and inner plates 38 constituting the clutch means 25 consisting of a multi-disc clutch are arranged alternately.The outer plate 37 is spline engaged with the inner periphery of the housing 21, The plate 38 is splined to a flange hub 39 attached to the outer periphery of the rotating shaft 22.

An annular groove 45 centered around the rotating shaft 22 is formed at one end of the side plate 27 facing the rotating member 41;
This annular groove 45 opens into a pressure acting chamber 47 between the side plate 27 and the piston 24 via a plurality of pressure introduction holes 46 on the circumference. A guide ring 48 is rotatably housed in the annular groove 45, and the guide ring 48 is coupled to the blade 42 so as to be rotated together with the blade 42. The guide ring 48 has pressure introduction ports 49 formed at two places on its circumference, and these pressure introduction ports E/49 are located close to the pressure side of the blade 42 during forward torque transmission (when reverse torque transmission is performed, the pressure introduction ports 49 are located close to the pressure side of the blade 42). The opening is at the farthest position from the pressurizing side. The pressure introduction port 49 is communicated with the pressure action chamber 47 via the pressure introduction hole 46 .

The pressure generating section 23 having the above-described configuration allows the two shafts 15.
16 rotates relative to each other, and the rotating member 41 is rotated relative to the housing 21.
When the pressure chamber 43 is relatively rotated, the high viscosity fluid 44 filled in the pressure chamber 43 is forcibly moved between the two opposing surfaces by the blade 42 at a flow rate corresponding to the rotational speed difference. At this time, pressure proportional to the relative rotational speed difference of the rotating member 41 is generated due to viscous friction on both wall surfaces of the bottom surface of the housing 21 and the end surface of the side plate 27. In other words, this pressure has a pressure distribution with a continuous pressure gradient from point A (highest pressure) to point B (lowest pressure), assuming that the pressure side of the blade 42 is point A and the non-pressure side is point B. occurs as.

In this case, when the blade 42 rotates clockwise relative to the housing 21 (hereinafter referred to as positive torque transmission), the pressure introduction port 49 opened in the guide plate 48 that rotates as the blade rotates. 42
The pressure application chamber 4 is located in a high pressure area close to the pressurizing side A of the
The pressure introduced into piston 7 is increased, and the thrust acting on piston 24 is increased.

Therefore, during positive torque transmission, the plurality of outer plates 37 and inner plates 38 are frictionally engaged by the large thrust acting on the piston 24, and sufficient rotational torque is transmitted between the two shafts 15 and 16 via the clutch means 25. be done. That is, the transmitted torque for differential rotation is as shown by the solid line in FIG.

On the other hand, when the blade 42 rotates counterclockwise relative to the rotary housing 21 (hereinafter referred to as reverse torque transmission), a pressure introduction port 49 opened in the guide plate 48 that rotates accordingly. is located in a low pressure region close to the non-pressurized side of the blade 42, and the pressure introduced from the pressure introduction port 49 into the pressure action chamber 47 via the pressure introduction hole 46 is low, and the thrust acting on the piston 24 is reduced. Ru.

Therefore, during reverse torque transmission, the plurality of outer plates 37 and inner plates 38 are frictionally engaged by a small thrust acting on the piston 24, and the transmitted torque for differential rotation is small as shown by the broken line in FIG. Become.

In the above embodiment, the pressure introduction port 49 is opened at a position close to the pressurizing side of the blade 42 during forward torque transmission, and a large difference is created between the forward torque transmission characteristic and the reverse torque transmission characteristic. However, by shifting the opening position of the pressure introduction port 49 from the pressurizing side of the blade 42, it is possible to lower the forward torque transmission characteristic and increase the reverse torque transmission characteristic, thereby reducing the difference.

Therefore, by configuring the guide plate 48 to be coupled to the blade 42 so that its angle can be adjusted, the characteristics can be set arbitrarily even in the same structure by assembling the same structure.

<Effects of the Invention> As described above, the present invention has a configuration in which a pressure introduction port communicating with the piston action chamber is opened in the guide ring that rotates integrally with the blade, so that the pressure in the high pressure region is reduced during positive torque transmission. can be introduced into the piston action chamber from the pressure introduction port, and conversely, when transmitting reverse torque, pressure in the low pressure region can be introduced from the pressure introduction port into the piston action chamber. The transmission characteristics can be made different, and the reverse torque transmission characteristics can be lowered compared to the positive torque transmission characteristics. This has the advantage that it is possible to absorb the circulating 1-lux, prevent vibrations and muffled noise caused by the difference in rotational phase between the front and rear wheels during the running process, and reduce disturbances during ABS control.

Moreover, according to the present invention, there is also an effect that the positive torque transmission characteristic can be increased without increasing the size of the device.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a cross-sectional view of the driving force transmission device, and FIGS. 2 and 3 are sections from ■ to ■ in FIG.
4 is a diagram showing transmission torque characteristics with respect to differential rotation. 21... Housing, 22... Rotating shaft, 24...
Piston, 25... Clutch means, 27... Side plate, 40... Space, 42... Blade, 4
7...Pressure action chamber, 4th...Guide ring, 49...
・Pressure introduction port.

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 and a side plate are housed in the housing, a pressure acting chamber is formed between the piston and the side plate, and a pressure acting chamber is formed between the piston and the side plate. A space is provided on the side of the plate, 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. Contains blades that generate pressure according to differential rotation,
A driving force transmission device comprising a guide ring that rotates integrally with the blade, and a pressure introduction port communicating with the pressure acting chamber opened in the guide ring at a position corresponding to a high pressure region of the pressure chamber.