JPH0137248Y2 - - Google Patents

Description

[Detailed explanation of the invention] A. Purpose of the invention a. Industrial application field The present invention relates to a limited-slip differential used in automobiles and other vehicles. The present invention relates to a differential device with a differential limiting mechanism that allows for selective use of differential limiting.

B. Prior Art Differential limiting devices for automobiles and other vehicles allow both wheels to rotate at the same rate when the vehicle is traveling straight, and when the vehicle is turning, the angular velocity of both wheels is changed by a differential differential to allow smooth turning. In addition, if one wheel enters a place with a small coefficient of friction, such as a muddy ground or frozen road surface, the differential is limited by external means or other means to provide sufficient torque to the other wheel, making it possible to escape. That is.

Various methods have been proposed to limit the differential, and one that is close to the present invention is, for example, the one described in Japanese Utility Model Publication No. 36589/1989.
This is a system in which a friction clutch, a cylinder and a piston are installed in a differential box, and fluid pressure is applied to the piston from the outside via a rotary joint to limit the differential.

c. Problems to be solved by the invention In the conventional limited-slip differential described above, in order to reduce the length of the differential box in the axle center line direction, instead of reducing the number of friction plates, the number of friction clutches is reduced. The friction surface is formed to have as large a diameter as possible. Correspondingly, the piston/cylinder is short in the axial direction, but has a larger diameter than the inner diameter of the bearing supporting the differential box.

Therefore, when this carrier assembly is assembled into a vehicle and pressurized with hydraulic pressure, air will accumulate in at least the cylinder above the inner diameter of the bearing that supports the differential box. However, normal axle boxes do not have adjustment holes, so the trapped air interferes with the piston's operation. Therefore, some models have installed a bleeder valve on the larger diameter side of the cylinder chamber of the differential box to allow air to bleed, but this requires a larger axle box, and a special adjustment hole is installed on the top of the axle box. Even if it was formed, it was difficult for the air to escape because the car body was close to the top.

Furthermore, when this carrier assembly is attached to a vehicle and pressurized with air, water accumulates at least in the cylinder below the inner diameter of the bearing that supports the differential box. However, similar to the above, normal axle boxes do not have adjustment holes, so accumulated water interferes with the operation of the piston. Therefore, similar to the above, some models have installed a bleeder valve on the larger diameter side of the cylinder of the differential box to drain water, but the axle box has also been made larger or a special adjustment hole has been installed in the axle box. It requires time and effort to install, drain the lubricating oil from the axle box, and then drain the water.

Moreover, since the oil passage is connected between the carrier on the stationary side and the differential box on the rotating side, a complicated and expensive rotary joint is required, and fluid leaks from the rotary joint, interfering with the operation of the piston. There were problems such as the effect of

The present invention relates to a differential gear with a differential limiting mechanism, and is an attempt to solve the problems of the above-mentioned conventional differential gear. That is, the first purpose of the present invention is to make it possible to easily and reliably bleed air when pressure oil is used for operating pressure, and to bleed water easily and reliably when air is used for operating pressure. It is. Further, even when the mounting direction is upside down due to vehicle specifications, air and water can be removed easily and reliably in the same way. The second purpose is to eliminate the need for complicated and expensive rotary joints between fluid paths and to eliminate fluid leakage.

B. Structure of the invention a. Means for solving the problems The differential device with a differential limiting mechanism of the invention has an input pinion 1, a ring gear 2, and a differential mechanism 3, and the piston 4 is moved by external fluid pressure. In a differential limiting device in which a friction clutch 5 is operated by a friction clutch 5 to switch between a normal differential and a limiting differential, the piston 4 is
A cylinder 7 that presses the cylinder 7 is fixed in the rotational direction, and a fluid inlet 9 is provided in the carrier cover 8, and a fluid passage 1 is provided that communicates with the carrier cover 8 in the vertical direction.
0, and bleeder valves 11 and 12 are installed at the upper and lower ends of the fluid passage 10, respectively, and the upper and lower parts of the fluid passage 10 and the upper and lower parts of the cylinder 7 are connected by joints 13 and 14, respectively. This is what happens.

In the above configuration, the differential mechanism 3 in the carrier 6
is the ring gear 2 that meshes with the input pinion 1.
, fix the differential case 15 and clutch case 16 and insert the pinion shaft 17 inside the differential case 15.
A suitable number of differential pinions 18 are provided which are rotatable around the pinion shaft 17, and are meshed with a differential side gear 20 on an axle 19 orthogonal to the pinion shaft 17.

The rotational direction of the cylinder 7 can be locked by, for example, protruding a rotation stopper 21 on the carrier cover 8 as shown in the figure, and forming a groove 22 in the same direction as the centerline of the axle 19 on the cylinder 7 side. It is only necessary to lock the stop member 21, but the present invention is not limited thereto. Note that the cylinder 7 is preferably attached by being screwed onto the inner periphery of the ring nut 31, which is the fixed side.

In the figure, reference numeral 23 denotes a rotation stopper member for the piston 4, which is protruded from the cylinder 7 and attached to the piston 4 by the axle 1.
It is engaged in a groove portion 24 formed in the same direction as the center line direction of 9. 25 is a rolling bearing, piston 4
and the slide sleeve 26. 2
7 is a pressure plate, 29 is a return spring, 3
0 is a differential box. Note that the joints 13 and 14 do not have to have a special structure, and may be, for example, a simple movable joint as shown in the illustrated example, or other types.

b. Effect The operating state of the present invention will be explained below.

A working fluid such as pressurized oil or air is supplied to the fluid inlet 9 of the carrier cover 8 by an external pump (not shown).
Pressure-fit into the fluid path 10 from the inside. This fluid is at fitting 1
3 and 14, and presses the piston 4 with fluid pressure, causing the rolling bearing 25, slide sleeve 26, and pressure plate 27
is pushed to the right in FIG. 1 to bring the friction clutch 5 into tight contact and limit the differential movement.

In the above case, if pressure oil is used as the fluid, air will accumulate in the upper part of the cylinder 7, and if air is used as the fluid, water will accumulate in the lower part of the cylinder 7, inhibiting the operation of the piston 4. It may interfere. Therefore, in the above-mentioned models that use pressure oil, by loosening the bleeder valve 11 located at the upper position in FIG. 2, the joint 13 connected to the upper part of the air cylinder 7
through the fluid path 10 and the bleeder valve 11
protrude from In addition, in the case where air is used, by loosening the bleeder valve 12 located at the lower position in the figure, water is released from the joint 14 connected to the lower part of the cylinder 7.
through the fluid path 10 from the bleeder valve 12
leaked from. After that, both bleeder valves 11 and 12 are tightened.

Note that switching to the normal differential state can be achieved by switching the fluid pressure to the drain pressure. As a result, the force of the return spring 29 pushes the pressure plate 27, slide sleeve 26, rolling bearing 25, and piston 4 back to the left in FIG.
Normally, a differential is created by providing sufficient clearance between the two.

C. Effects of the invention As is clear from the above, the invention has the following effects.

a Water or air can be easily and reliably removed from the cylinder. In other words, with conventional cylinders and pistons housed in a differential box, the differential box usually does not have a bleeder valve or other adjustment holes, so water or air cannot be removed from the cylinder, which impedes piston operation. was. However, in the present invention, bleeder valves are provided at both ends of the fluid path of the carrier cover, which is connected to the cylinder via a joint. Therefore, if air accumulates in the cylinder, it can be easily and reliably extracted from the bleeder valve located at the upper position, and if water accumulates within the cylinder, it can be easily and reliably extracted from the bleeder valve located at the lower position. be able to. This is the same even if the upper and lower mounting positions are reversed depending on the vehicle specifications, air can be extracted from the bleeder valve located at the upper position, and water can be extracted from the bleeder valve located at the lower position, so that the piston is always can operate smoothly.

b Eliminates the need for complicated and expensive rotating joints. In other words, with conventional cylinders and pistons housed in a differential box on the rotating side, the connection between the carrier on the stationary side and the cylinder on the rotating side in the middle of the fluid path requires the use of an expensive rotary joint with a complicated structure. I didn't get it. In contrast, in the present invention, the cylinder is integrally attached to the carrier on the stationary side, so the fluid path is connected only between the stationary sides, eliminating the need for complicated and expensive joints, and eliminating the need for complicated and expensive joints. It can be replaced with a fitting.

c. Fluid leakage from rotating parts can be eliminated. That is, in the case where the conventional cylinder/piston is housed in the differential box on the rotating side as described above, a fluid path is connected from the stationary side to the rotating side.
Therefore, it was necessary to apply high pressure to the fluid, and fluid leakage occurred at the connection with the rotating side. However, in the present invention, the cylinder is integrally attached to the carrier on the fixed side, and the fluid path is connected only between the fixed sides. Therefore, airtightness between the fluid channels can be easily and reliably achieved, and fluid leakage can be eliminated.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a plan view of the entire device, and FIG. 2 is an enlarged left side view of a portion of the device. Drawing code, 1...Input pinion, 2...Ring gear, 3...Differential mechanism, 4...Piston, 5...
Friction clutch, 6...Carrier, 7...Cylinder, 8...Carrier cover, 9...Fluid inlet,
10... Fluid path, 11, 12... Bleeder valve, 13, 14... Joint.

Claims (1)

[Scope of utility model registration request] A differential that has an input pinion 1, a ring gear 2, and a differential mechanism 3, and uses external fluid pressure to slide a piston 4, which operates a friction clutch 5 to switch between normal differential and limited differential. In the restriction device, a cylinder 7 that presses the piston 4 is fixedly attached to the carrier 6 on the fixed side thereof in the rotational direction, and a fluid inlet 9 is provided in the carrier cover 8 and communicates with the carrier cover 8 in the vertical direction. A fluid passage 10 is formed between the upper and lower parts of the fluid passage 10 and between the upper and lower parts of the cylinder 7, respectively.
3 and 14, and bleeder valves 11 and 12 are installed at the upper and lower ends of the fluid path 10, respectively.
Differential device with differential limiting mechanism.