JPH0251626A - Device for transmitting driving force - Google Patents

Abstract

PURPOSE:To improve the durability of a clutch in the driving-force transmission of a four-wheel-drive vehicle by recessedly providing a sub-chamber in a cylinder housing opposite to a space portion, partitioning the sub-chamber from the space with a partition board, and housing a high-viscous fluid also in this sub- chamber. CONSTITUTION:A space portion 43 in which a high-viscous fluid is sealed is provided on the side of an operating piston 36. A sub-chamber 50 is recessedly provided on a cylinder housing 32 opposite to this space portion 43. The portion between this sub-chamber 50 and the space portion 43 is partitioned by a partition board 51 on which connecting holes 52 are provided. The high-viscous fluid is also housed in the sub-chamber 50. Since the sealing quantity of the high-viscous fluid is increased by the amount of the capacity of the sub-chamber 50 increasing the expanding quantity of the high-viscous fluid due to temperature rise, a transmission torque can be greatly increased with respect to temperature rise. Thereby, the durability of a clutch can be improved.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention provides a driving force transmission device that transmits rotational power between two relatively rotatable shafts when differential rotation occurs between the two shafts. It is related to.

<Prior art> In a torque transmission device for a four-wheel drive vehicle, torque is transmitted between a front wheel drive shaft (input shaft) and a rear wheel drive shaft (output shaft) within a sealed chamber formed between the two shafts. A multi-disc clutch is arranged, and an operating piston is provided that controls the transmission torque of the multi-disc clutch by the hydraulic pressure of a hydraulic pressure generating means that generates a hydraulic pressure corresponding to differential rotation between a front wheel drive shaft and a rear wheel drive shaft. A driving force transmission device is known, for example, from Japanese Patent Laid-Open No. 60-252026.

The hydraulic pressure generating means of this device is configured to discharge hydraulic pressure between the front wheel drive shaft and the rear wheel drive shaft in accordance with the differential rotation of both shafts.
A lange type or vane type oil pump is installed, and pressure oil discharged from the oil pump 1 is introduced into a cylinder chamber on one side of the working piston through a pressure introduction path formed on one of both shafts. This is a configuration in which the multi-disc clutch is pushed in the engaging direction by an operating piston.

<Problems to be Solved by the Invention> However, in a torque transmission device such as the one disclosed in JP-A No. 60-252026, it is necessary to incorporate an oil pump between the two shafts, and the oil pump discharges There are problems in that the configuration is complicated, such as the need to form a passage leading to the hydraulic clutch, and the size and cost are high.

In order to solve these problems, the present applicant has provided a torque transmission device as disclosed in the above-mentioned Japanese Patent Application No. 75240/1982. By the way, in this case, as shown in Fig. 3, the transmitted torque generally increases as the differential rotation increases.
It rises like a curve, but because the volume of the space in the pressure generating means is small and the amount of high viscosity fluid sealed therein is small, the amount of expansion of the high viscosity fluid with respect to temperature rise is small; As time passes with the clutch engaged, the generated pressure decreases due to changes in the viscosity of the high-viscosity fluid due to temperature rise, and the transmitted torque may decrease as shown by curve 8 in FIG. 4.

Means for Solving the Problems> The present invention has been made in view of the above problems.
Its characteristic configuration is a driving force transmission device including a clutch means disposed between two relatively rotatable shafts and transmitting torque between the two shafts, and an actuating piston that controls the transmitted torque of the clutch means. , a cylinder housing housing the actuating piston is connected to one of the two shafts, a rotating shaft rotatably supported by the cylinder housing is connected to the other, and a space is provided in the cylinder housing on the side of the actuating piston. A rotor is housed in the space, the rotor is connected to one of the two shafts, a blade is provided on the rotor, and a sub-chamber is formed in a portion of the cylinder housing facing the space. The auxiliary chamber and the space are partitioned by a partition plate having a communication hole, and the space and the auxiliary chamber are filled with high viscosity that is forcibly moved within the space by the blade due to the differential rotation between the cylinder housing and the rotating shaft. It is made by enclosing a fluid.

<Function> With the above configuration, the amount of high viscosity fluid enclosed is increased by the space of the pressure generating means and the auxiliary chamber communicating with the space through the communication hole of the partition plate, and the high viscosity fluid increases due to temperature rise. The expansion indigo becomes larger and the transmitted torque increases as the temperature rises.

Example of actual glaze> Hereinafter, an example of actual glaze of the present invention will be explained based on the drawings. In FIG. 1, 30 is a driving force transmission device. 32 is a cylinder housing to which one end of the input shaft 15 is coupled. 3
Reference numeral 1 indicates a housing cap, which seals the inside of the cylinder housing 32. A rotary shaft 33 is rotatably supported on the cylinder housing 32 and the housing cap 31 concentrically with the cylinder housing 32 .

One end of the output shaft 16 is coupled to the rotating shaft 33 .

Clutch lubricating oil is sealed in the cylinder housing 32, and a plurality of outer grates 37 are arranged in parallel on the inner periphery of the cylinder housing 32 to be engaged in the rotational direction by splines and movable in the axial direction. has been done.

On the other hand, a plurality of inner plates 38 are provided on the outer periphery of the rotating shaft 33.
are engaged in the rotational direction by a spline and are arranged in parallel so that they can move in the axial direction. These outer plates 37 and inner plates 38 are arranged alternately and constitute a multi-plate clutch 40 as a clutch means. An operating piston 36 is slidably fitted in the cylinder housing 32 between a multi-disc clutch 40 and the cylinder housing 32, and the operating force of the operating piston 36 is transmitted to the multi-disc clutch 40.

A space 43 consisting of an axial gap is provided on the side of the actuating piston 36 between the cylinder housing 32 and the space 43 consisting of the axial gap. A rotor 41 is slidably housed therein. As shown in FIG. 2, blades 42 are formed in the rotor 41 in the diametrical direction.

The rotor 41 has a center portion splined to the outer periphery of the rotating shaft 33 and is rotatable relative to the cylinder housing 32 . The outer periphery of the rotor 41 may be spline-engaged with the inner periphery of the cylinder housing 32 so that the rotor 41 can rotate relative to the rotating shaft 33. As a result, the space 44 formed by the axial clearance is circularly formed by the plurality of blades 42. Divided circumferentially.

Furthermore, the space portion 43 of the cylinder housing 32
A subchamber 50 is recessed in a region facing the subchamber 50, and a partition plate 51 is provided between the subchamber 50 and the space 43.

This partition plate 51 has communication holes 5 such as elongated holes or round holes.
2 is opened, and the space portion 43 and the subchamber 50 communicate with each other via this communication hole 52. A high viscosity fluid 23 such as silicone oil is sealed in the space 43 and the subchamber 50.

With the above configuration, when the cylinder housing 32 and the rotating shaft 33 differentially rotate, the high viscosity fluid 23 sealed in the space 43 is moved between the two closely spaced surfaces by the blade 42 at a flow rate corresponding to the rotational speed difference. The viscosity I with both end surfaces of the cylinder housing 32 and the working piston 36 is forcibly moved.
Internal pressure is generated by rubbing. That is, for example, when the rotor 41 rotates clockwise with respect to the cylinder housing 32 in FIG. 2, internal pressure is generated with high pressure on the A and A sides of the blade 42 and low pressure on the B and 8 sides. This internal pressure presses the actuating piston 36 in a direction that presses against the multi-disc clutch 40, and performs a torque transmitting action as shown by curve A in FIG. 3.

Further, when the cylinder housing 32 and the rotating shaft 33 are not differentially rotated, no internal pressure is generated by the high viscosity fluid 23 in the space 43 consisting of the axial gap in which the blade 42 is housed, and a large amount of pressure is generated. The plate clutch 40 does not perform a torque transmission function.

By the way, as time elapses while the multi-disc clutch 40 is engaged due to the differential rotation, the temperature of the high viscosity fluid 23 rises and the viscosity of the high viscosity fluid 23 changes, causing
The transmitted torque tends to decrease as shown by the curve, but due to this temperature rise, the high viscosity fluid 23 enclosed in the space 43 and the auxiliary chamber 50 increases in volume and expands, so that the amount of pressure generated by the actuating piston 36 increases. The pressing force of the plate clutch 40 is increased, and the transmitted torque increases significantly as shown by the fourth curve.

In the above embodiment, the clutch means is a multi-disc clutch 40.
However, it is not necessarily limited to the multi-disc clutch 40.

<Effects of the Invention> As described above, the present invention provides a high viscosity fluid on the side of the actuating piston that controls the clutch means that transmits torque between two relatively rotatable shafts by differential rotation between the two shafts. The hydraulic pressure generating means is provided with an enclosed space, and faces the space, and the actuating piston presses the clutch means under internal pressure due to a high viscosity fluid generated in the space by rotation of a blade housed in the space. A sub-chamber is recessed in the cylinder housing, and the sub-chamber and the space are separated by a partition plate with a communication hole, so that the high-viscosity fluid can also be accommodated in the sub-chamber. Because of this, the amount of high viscosity fluid enclosed increases by the volume of the subchamber, and the amount of ms of high viscosity fluid increases due to temperature rise, so the transmitted torque increases significantly with respect to temperature rise, making it difficult to use with conventional equipment. Compared to this, it has the advantage of being easier to escape from mud etc. and improving the durability of the clutch.

[Brief explanation of the drawing]

The drawings show a practical example of the present invention; Fig. 1 is a sectional view of the driving force transmission device, Fig. 2 is a sectional view taken along the line ■-■ of Fig. 1, and Fig. 3 shows the torque transmission characteristics of the present invention. 4 are diagrams showing changes in transmitted torque between the present invention and the conventional method when the clutch is engaged. 31... Cap, 32... Cylinder housing,
33... Rotating shaft, 36... Operating piston, 40...
- Multi-plate clutch, 41... Rotor, 42... Blade, 43... Space, 50... Sub-chamber, 51... Partition plate, 52... Communication hole. Figure 1

Claims (1)

[Claims] A driving force transmission device comprising a clutch means disposed between two relatively rotatable shafts and transmitting torque between the two shafts, and an actuating piston controlling the transmission torque of the clutch means. A cylinder housing that accommodates the working piston is connected to the other side, and a rotating shaft rotatably supported on the cylinder housing is connected to the other side, a space is provided in the cylinder housing on the side of the working piston, and a space is provided in the cylinder housing on the side of the working piston. storing a rotor, connecting the rotor to either one of the two shafts, and providing a blade on the rotor;
A subchamber is formed in a portion of the cylinder housing that faces the space, the subchamber and the space are partitioned by a partition plate having a communication hole, and the cylinder housing and the rotating shaft are connected to the space and the subchamber. A driving force transmission device that encloses a high viscosity fluid that is forcibly moved within a space by the blades due to differential rotation of the blades.