JPH0332840Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to an improvement of a differential gear equipped with a differential limiting mechanism.

[Prior Art] Recently, a so-called viscose clutch disclosed in Japanese Utility Model Application Laid-Open No. 47-203 has been adopted as a differential limiting mechanism in place of a friction clutch.

This viscose clutch utilizes the viscous resistance of viscous fluid to limit differential movement, for example, due to the rotation speed difference between resistance plates provided on the axle and the differential case.

Comparing this viscose clutch and a friction clutch, we find that in the case of a friction clutch, there is no increase in torque even if the differential speed increases, so the limiting effect remains the same; Since it is a non-contact type, there are advantages such as no abnormal noise, less wear, and smooth operation.

[Problems to be solved by the invention] However, if this viscose clutch continues to be differentially operated, the temperature inside the working chamber will rise and the internal pressure will also rise, so there is a risk that the seal will break and the function will be impaired. It was hot.

Furthermore, the viscose clutch is structured so that the differential limiting effect only appears after differential rotation, so in some road conditions, such as when a wheel runs into mud, torque transmission may be momentarily delayed and the ability to escape may be affected. , compared to a friction clutch, it was lower and could not be released quickly.

This invention was devised in view of the above problems, and in a differential gear equipped with this type of viscose clutch, even if the internal pressure of the viscose clutch increases, the seal will not break. Another object of the present invention is to provide a differential device capable of quickly locking and escaping from mud, etc., and furthermore, capable of limiting differential movement depending on the magnitude of input torque.

[Means for Solving the Problems] In order to achieve the above object, this invention includes a pair of left and right side gears rotatably and axially movably provided inside a differential case, a pinion gear meshing with each side gear, and a pinion gear meshing with each side gear. A working chamber is formed between the back of one side gear and the differential case, a large number of resistance plates are connected to the side gear and the differential case alternately in the rotational direction within this working chamber, and hydraulic oil is sealed in the working chamber. The mechanism consisted of a clutch mechanism interposed between the back of the other side gear and the differential case.

[Operation] When the pressure in the working chamber increases, a thrust force is generated in the thrust direction, and one side gear presses the other side gear toward the friction clutch via the pinion gear, thereby limiting the differential.

[Example] Hereinafter, an example of this invention will be described in detail using the drawings.

The figure shows a differential device to which this invention is applied. between the axles 2 and 3, a pair of side gears 4 and 5 that are disposed opposite to each other on the left and right inside the differential case 1 and are slidably coupled to the protruding ends of the respective axles 2 and 3 by spline coupling; A pinion gear 6 is disposed perpendicularly to the side gears 4 and 5 and meshes with both side gears 4 and 5, and a pinion shaft 8 supports the pinion gear 6.

A shaft end of the pinion shaft 8 is movably supported along a long bearing groove 1a formed in the left-right direction inside the differential case 1.

In the figure, a viscose clutch 10 constituting a differential limiting mechanism is installed between the back of the left side gear 4 and the inner surface of the differential case 1, and a viscose clutch 10 is installed between the back of the right side gear 5 and the inner surface of the differential case 1. A plurality of clutch plates 11 constituting a friction-type differential limiting mechanism are interposed, which are alternately engaged in the rotational direction.

The viscose clutch 10 includes a ring-shaped partition plate 101 that is fluid-tightly fitted between the outer circumferential portion of the side gear 4 and the inner circumferential portion of the differential case 1, and a support provided to protrude into the interior of the differential case 1. Part 1
b is fluid-tightly and rotatably fitted to the outer periphery of the side gear 4, and a sealed working chamber 103 is formed between the back surface of the side gear 4 and the differential case 1 by the protrusion 102 formed on the back surface of the side gear 4. This is what I did.

Inside this working chamber 103, spline grooves 103a and 103b are cut in the inner periphery of the protruding portion 102 and the differential case 1, and the inner periphery of the resistance plates 104 and 105 are alternately formed in each of these spline grooves 103a and 103b. The outer periphery of the working chamber 103 is spline-coupled to partition the inside of the working chamber 103 into a labyrinth shape.

A high viscosity working fluid such as silicone oil is sealed inside the working chamber 103 having the above structure.

A spring pin 107 that projects into the bearing groove 1a is driven into the end of the partition plate 101 to prevent the spring pin 107 from tangling with the side gear 4.

Next, the operation of the differential device constructed as above will be explained.

When a differential occurs in the differential device, a rotational speed difference occurs between the protrusion 102 provided on the side gear 4 and the differential case 1, and a differential due to viscous resistance occurs between the resistance plates 104 and 105 of the working fluid in the working chamber 103. A limiting action takes place. This is exactly the same effect as a conventional viscose clutch.

If the differential continues, the temperature of the working fluid will rise and the differential limiting action will be reduced due to the drop in viscosity, but as the pressure in the working chamber 103 increases due to the rise in temperature, the side gear 4 will be pushed in the thrust direction. ,
The side gear 4 presses the other side gear 5 via the pinion gear 6, and as a result, the back surface of the side gear 5 presses against the clutch plate 11, so that differential movement is limited by the clutch plate 11.

Since the differential limiting action by the clutch plate 11 is of the torque responsive type, the viscose clutch 10
This means that it will work well even when the torque is exceeded.

FIG. 2 shows another embodiment of the present invention, in which the clutch plate 11 is connected to an elastic body such as a disc spring.
Apply initial torque by pressing with a. In this way, by applying an initial torque, even if differential rotation does not occur, a differential limiting action can be obtained in advance by the input torque, and after differential rotation occurs, the viscose clutch The differential limiting effect due to viscous resistance is also added, resulting in a strong differential limiting effect. Also, in this case, the increased internal pressure of the viscose clutch causes the side gears to move in the axial direction, thereby further compressing the clutch plate 11, resulting in a strong differential limiting action. .

[Effects of the invention] As explained in detail in the embodiments above, according to this invention, a thrust force is generated in the thrust direction in which the pressure in the working chamber increases, and one side gear flicks the other side gear via the pinion gear. The friction clutch is pressed against the friction clutch and the friction is immediately limited, so compared to the conventional differential limiting mechanism using only a viscose clutch, there is no seal breakage due to pressure rise, and even when the torque is large, the friction is immediately It has the advantage of being able to perform differential limiting.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a differential gear to which this invention is applied, and FIG. 2 is a partial sectional view showing another embodiment. 1... Differential case, 4, 5... Side gear, 6
... Pinion gear, 10 ... Viscose clutch, 11 ... Clutch plate, 103 ... Working chamber, 1
04,105...Resistance plate.

Claims (1)

[Scope of utility model registration request] A pair of left and right side gears that are rotatably and axially movable provided inside the differential case, a pinion gear that meshes with each side gear, an operating chamber formed between the back of the one side gear and the differential case, and a A large number of resistance plates are each connected to the side gear and the differential case in the rotational direction, and a working fluid is sealed in a working chamber.
A differential device comprising a clutch mechanism interposed between the back of the other side gear and the differential case and generating a fastening force depending on the magnitude of input torque.