JPH02120529A - Driving force transmission - Google Patents

Abstract

PURPOSE:To improve degree of freedom of transmitting characteristic by rotatably providing a guide ring to a side plate, forming thereon engaging projections which enable relative following rotation of a guide plate for 2 prescribed angle, and opening a pressure introducing port communicated with a pressure actuating chamber on the guide ring. CONSTITUTION:At normal torque transmission, engaging projections 50A are engaged and a guide plate 48 is accompaniedly rotated by rotation of a blade 42, a pressure introducing port 49 opened on the plate 48 is kept in a fixed relative position to the blade 42, and pressure is introduced from the port 49 to a pressure actuating chamber 47. At reverse torque transmission, the blade 42 is relatively rotated to the plate 48, the plate 48 is accompaniedly rotated in the engaged condition with one side engaging projections 50B, and pressure is introduced from the port 49 to the chamber 47. In this case by instituting the position of the port 49 in the high pressure territory of the pressure chamber, transmitting torque against differential rotation increases, on the contrary, by instituting the position of the port 49 in the low pressure territory, transmitting torque against differential rotation decreases.

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> Accordingly, the present invention is capable of converting any pressure point in the above-mentioned pressure distribution into piston thrust. A rotating shaft rotatably supported by the housing is connected to the housing, 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 side plate 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 in the space by differential rotation of the two axes, and the viscous friction causes a difference between the two axes. A blade that generates pressure according to dynamic rotation is housed, a guide ring is rotatably provided on the side plate, an engagement protrusion is formed on the guide ring to rotate the blade as the blade is relatively rotatable by a predetermined angle, and A pressure introduction port communicating with the pressure acting chamber is opened in the guide ring.

<Operation> With the above configuration, when the two axes rotate relative to each other, the high viscosity fluid in the space is forced to move 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. Occurs.

In this case, when transmitting positive torque, one of the engagement protrusions is engaged by the rotation of the blade, the guide plate is rotated, and the pressure introduction port opened in this guide plate maintains a constant positional relationship with respect to the blade. is maintained. Thus, pressure is introduced into the pressure action chamber from the pressure introduction port.

On the other hand, during reverse torque transmission, the blade rotates relative to the guide plate, and the guide plate is rotated while being engaged with one of the engagement protrusions, and the pressure application chamber is opened from the pressure introduction port. pressure is introduced.

In this case, if the pressure introduction port is located in the high pressure region of the pressure chamber, the piston thrust will be increased and the torque transmitted to the differential rotation can be increased; conversely, if the pressure introduction port is located in the low pressure region of the pressure chamber For example, the piston thrust is reduced and the transmitted torque for differential rotation can be reduced.

<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 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. 41 is the center part
As shown in the figure, the spline is engaged with the outer periphery of the rotating shaft 22. 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 this clutch chamber 36 is filled with lubricating oil. has been done. A plurality of outer plates 37 and inner plates 38 constituting the clutch means 25 consisting of a multi-plate clutch are arranged alternately in the clutch chamber 36. The outer plates 37 are spline-engaged with the inner periphery of the housing 21, and The plate 38 is splined to a clutch 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 housed in the annular groove 45 so as to be rotatable within the rotation plane of the blade 420.

The blade 42 is disposed on the circumference of the guide ring 48.
two sets of engagement protrusions 5 that engage in relative rotation at a predetermined angle.
0A and 50B are provided protrudingly. In other words, the engagement protrusion 5
0A and 50B are arranged so as to sandwich the blade 42 with play α, so that when the blade 42 rotates clockwise in FIG. 2 relative to the housing 21 (hereinafter referred to as positive torque transmission), , one engagement projection 50A is engaged with the blade 42 and the guide ring 4
8 is rotated along with the blade 42, and when the blade 42 rotates counterclockwise in FIG. 2 relative to the housing 21 (hereinafter referred to as the time of reverse torque transmission),
The other engaging protrusion 50B is engaged with the blade 42 and rotated. Said guide ring 4
8 has pressure introduction ports 49 formed at two locations on its circumference, and these pressure introduction ports 49 are connected to the one engagement protrusion 50.
It is opened at a position close to A. The pressure introduction port 49 is connected to the pressure action chamber 47 through the pressure introduction hole 46.
is communicated with.

The pressure generating section 23 having the above-mentioned 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 is generated as 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. do.

In this case, when transmitting positive torque, a pressure introduction port 49 opened in the guide plate 48 rotates accordingly.
is held in a high pressure region close to the pressurizing side A of the blade 42, and the pressure introduced from this pressure introduction port 49 into the pressure action chamber 47 through the pressure introduction hole 46 increases, and the thrust acting on the piston 24 increases. 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 the
Sufficient rotational torque is transmitted between the C2 shafts 15 and 16.

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

When the torque transmission direction is reversed from this state and a reverse torque transmission state is reached, the blade 42 and the guide plate 48 are rotated relative to each other by the amount of play α, and the blade 42 is engaged with the other engagement protrusion 50B (see Fig. 2). (two-dot chain line), the guide plate 48 is rotated. As a result, the pressure introduction port 49 opened in the guide plate 48 is connected to the blade 42.
The pressure introduced into the pressure action chamber 47 from the pressure introduction port 49 through the pressure introduction hole 46 is relatively 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-mentioned embodiment, an example was described in which the transmission characteristics were different between normal torque transmission and reverse torque transmission, but as shown in FIG. 5, the relative rotation angle between the blade 42 and the guide plate 48 is By setting β (> α), the pressure introduction port 49 can be located close to the pressure side of the blade 42 even during reverse torque transmission, and the transmission characteristics are improved both during forward torque transmission and reverse torque transmission. can be kept the same and the piston thrust can be increased.

In this way, by configuring the guide plate with the pressure introduction port open so that it can rotate relative to and integrally with the blade, the following effects can be expected.

(1) By locating the pressure introduction port in the high pressure region of the pressure chamber, the piston thrust can be increased and the required transmission torque can be obtained with a compact configuration.

(2) It is possible to provide a difference in transmission characteristics between forward torque transmission and reverse torque transmission, and it is possible to absorb circulating torque and suppress vibrations during reverse torque transmission.

(3) A highly flexible transmission characteristic can be obtained during forward torque transmission and reverse torque transmission.

(4) A dead zone can be provided against vibrations that repeat forward and reverse rotations, and torque vibrations can be damped.

<Effects of the Invention> As described above, the present invention has a configuration in which a pressure introduction port that communicates with the piston action chamber is opened in the guide ring that can rotate relative to and integrally with the blade, so that the pressure on the blade is reduced. By rearranging the introduction ports, it becomes possible to convert any pressure point in the pressure distribution in the pressure chamber into piston thrust, and it becomes possible to improve the degree of freedom in transmission characteristics.

[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, and FIG. 5 is a sectional view corresponding to FIG. 2 showing another embodiment of the present invention. 21... Housing, 22... Rotating shaft, 24...
Piston, 25... Clutch means, 27... Side plate, 40... Space, 42... Blade, 4
7... Pressure action chamber, 48... 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 guide ring is rotatably provided on the side plate,
A driving force transmission device, wherein the guide ring is formed with an engagement protrusion that rotates the blade by a predetermined angle relative to each other, and the guide ring is provided with a pressure introduction port that communicates with the pressure action chamber.