JPS6235621Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field]

The present invention relates to an improvement of a differential limiting device used in a vehicle such as an automobile, and more particularly to a differential limiting device in which the differential limiting force of the differential device is made variable.

[Conventional technology]

FIG. 1 shows a conventional limited slip differential device using a multi-plate clutch device. To explain the conventional example in FIG. 1, 1 is a differential case, 2 is a pinion, 3 is a side gear, and 4 is a multi-plate clutch device, in which a pinion 2 and a side gear 3 are arranged in mesh with each other in the differential case 1. ing. The pinion 2 is rotatably fitted and attached to a spider 5 supported by the differential case 1, and side gears 3 are arranged on both left and right sides of the pinion 2. A multi-plate clutch device 4 is interposed between the back side of the side gear 3 and the differential case 1. As is well known, the multi-plate clutch device 4 consists of clutch plates 6 and thrust washers 7 arranged alternately.The clutch plate 6 is slidable in the axial direction on the cylindrical portion 3a of the side gear 3, but is integral in the rotational direction. The thrust washer 7 is similarly attached to the inner wall surface of the differential case 1 so as to be slidable in the axial direction and integrally in the rotational direction. As a result, the clutch plate 6 of the multi-plate clutch device 4 rotates together with the side gear 3, and the thrust washer 7 rotates together with the differential case 1. For this reason,
When relative rotation occurs between the differential case 1 and the side gear 3, that is, when a differential occurs between the left and right drive wheels, a frictional force is generated between the clutch plate 6 and the thrust washer 7, which acts to limit the differential. Note that a coil spring 8 is inserted between the left and right side gears 3, and constantly applies preload to the multi-disc clutch device 4. For this reason, the differential limiting action is performed under a constant differential limiting force as a constant frictional force is always applied between the clutch plate 6 and the thrust washer 7 of the multi-plate clutch device. Further, a locking multi-plate friction clutch is provided between one of the side gears and the differential case, and this friction multi-plate clutch is configured to be pressed against the differential case by a pressure piston of a hydraulic cylinder device, thereby locking the differential gear (so-called A differential lock device has also been proposed that switches between a locked differential (lock differential) and an open differential (so-called normal differential). (For example, Utsukai 53
-Refer to Publication No. 112033).

[Problem that the invention attempts to solve]

However, in the conventional differential limiting device having the above-described configuration, a preload is applied to the multi-disc clutch device 4 by the coil spring 8 or the like to constantly apply a constant differential limiting force. For this reason, differential limiting force acts even under differential conditions on normal roads, which may affect the operability of the steering wheel or cause problems such as premature wear of the tires that are the driving wheels. . In addition, if you weaken the differential limiting force to solve this problem, the differential limiting force will be insufficient on muddy or snowy roads where the tire's coefficient of ground friction is low.
This causes a problem that the intended purpose of differential restriction cannot be fully achieved. As a result, it becomes difficult for the vehicle to escape, resulting in poor running performance. Further, the differential lock device described in the above-mentioned Japanese Utility Model Publication No. 53-112033 has poor running performance on snowy roads, gravel roads, and the like. In other words, when the differential rotation is locked (so-called lock differential), the left and right tires are driven at the same rotation speed, so if the load distribution between the left and right tires changes, it is easy to spin (for example,
Even if you just step on the brakes, it will spin). vice versa,
In the unlocked state (so-called normal differential), free differential rotation of the left and right tires is allowed, which caused problems such as tires being prone to slip. Therefore, the present invention was made to solve the above-mentioned conventional problems, and its purpose is to:
The objective is to improve running performance by changing the differential limiting force depending on the condition of the road surface on which the tires touch the ground.

[Means to solve the problem]

Therefore, the present invention employs the following configuration as a means for solving the above-mentioned problems. That is, the present invention provides an actuator device that presses the side gear of the differential against the differential case in response to the hydraulic pressure generated in the hydraulic pressure generating device by operating an operating means installed in the driver's cab, and presses the side gear of the differential device against the differential case. The present invention is characterized in that the differential limiting force of the differential device is changed in at least three stages by changing the pressing force of the side gear on the differential case. Specifically, using Figure 2 as an example,
The vehicle differential limiting device of the present invention includes an operating means 9 provided in a driver's cab, a hydraulic pressure generating device 16 that generates hydraulic pressure by operating the operating means 9, and a hydraulic pressure generating device 16 that receives the hydraulic pressure generated by the hydraulic pressure generating device 16. and an actuator device 22 that acts in a direction to press the side gear 3 of the differential device against the differential case 1. The pressing force of the side gear 3 against the differential case 1 is changed in accordance with the oil pressure generated by the oil pressure generating device 16, and the differential limiting force of the differential device is changed in at least three stages.

[Effect]

According to the above-mentioned means, when the operating means 9 provided in the driver's cab is operated, a corresponding hydraulic pressure is generated in the hydraulic pressure generator 16. The hydraulic pressure generated in the hydraulic pressure generating device 16 is supplied to the actuator device 22. Then, the actuator device 22 presses the side gear 3 of the differential device against the differential case 1 with a force corresponding to the oil pressure generated in the oil pressure generator 16. As a result, a frictional force is generated between the side gear 3 of the differential device and the differential case 1, and a differential limiting action is performed. The differential limiting force changes in at least three stages depending on the oil pressure generated by the oil pressure generator 16. Therefore, from a general differential device to a powerful differential limiting device, the differential device can be freely selected and used.

【Example】

Hereinafter, embodiments of the present invention will be described in detail based on the drawings. Figures 2 to 4 show a differential limiting device for a vehicle according to an embodiment of the present invention, with Figure 2 being a schematic sectional view and Figure 3 being viewed from the direction of arrow Y in Figure 2. FIG. 4 is a sectional view showing a state in which the differential limiting cylinder device and the collar are connected, and FIG. 4 shows the collar alone, with a being a longitudinal sectional view and b being a side view. This embodiment can be roughly divided into the following as shown in FIG.
It is comprised of an operating system A, a hydraulic operating system B that generates hydraulic pressure by operating the operating system A to control the differential, and a differential system C that has a differential limiting element. The operating system A has an operating lever 9 as an operating means installed in the driver's cab of the vehicle.
is connected to a link 11 via a coil spring 10 as a buffer mechanism. Then, by moving the operating lever 9 up and down in the direction of the arrow, the link 11
The rotary movement of the link 11 causes the piston 1 of the hydraulic operating system B, which will be described later, to rotate via the piston rod 13 attached to the link 11.
Activate 7. The operating lever 9 is provided with a serrated locking portion 9a as a mechanism for maintaining a predetermined position when the operating lever 9 is operated up and down, and a locking piece that engages with the locking portion 9a 14 is attached with a spring 15 arranged on the back. Hydraulic operating system B includes a master cylinder device 16 as a hydraulic pressure generating device, and this master cylinder device 16.
The differential limiting cylinder device 22 serves as an actuator device that operates a differential device system C, which will be described later, in response to hydraulic pressure from the differential device. The master cylinder device 16 generates hydraulic pressure by operating the piston 17, and supplies it to the left and right differential limiting cylinder devices 22 via the left and right pipes 18. The piston 17 is actuated by the rotational movement of the link 11 of the operating system A, as described above. A reservoir tank 19 is provided in the master cylinder device 16 via a pipe 20, and is used to replenish oil when the master cylinder device 16 runs out of oil. Specifically, a valve 21 for closing the connection port 20a is seated and attached to the connection port 20a of the master cylinder device 16 with the piping 20 by the spring force of a coil spring 35 interposed between the piston 17 and the connection port 20a. There is. As a result, piston 1
In the non-operating state of 7, replenishment from the reservoir tank 19 is possible, and in the operating state, the valve 21
The connecting port 20a is closed and hydraulic pressure is generated within the master cylinder device 16. The differential limiting cylinder device 22 is disposed on both left and right sides of the differential housing 23, and a piston 25 that is actuated by the hydraulic pressure supplied to the oil chamber 24 is fitted into the differential limiting cylinder device 22. There is. The piston 25 is configured to be actuated outward by hydraulic pressure in the oil chamber 24. In other words, the piston 25 of the right differential limiting cylinder device 22 operates in the right direction, and the left differential limiting cylinder device 22 operates the piston 25 in the left direction. There is. A fork 27 is attached to the rod 26 connected to the piston 25. The fork 27 is connected to a differential system C, which will be described later. The differential system C has a pinion 2 and a side gear 3 arranged in mesh with each other in a differential case 1, as in the conventional case. The pinion 2 is rotatably fitted and attached to a spider 5 supported by the differential case 1, and the side gears 3 are spline-fitted to the left and right axles so that power can be transmitted, respectively. Further, a multi-plate clutch device 4 is interposed between the left and right side gears 3 and the differential case 1. The multi-plate clutch device 4 has a structure similar to the conventional structure shown in FIG. 1, although the reference numerals are omitted, in which the clutch plate 6 is slidable on the side gear 3 and the thrust washer 7 is slidable on the differential case 1 in the axial direction. It is integrally attached in the direction. The frictional force generated between the clutch plate 6 and the thrust washer 7 acts to limit the operation. The cylindrical portion 3a of both side gears 3 is connected to the differential case 1.
The tapered roller bearing 28 is rotatably supported by the differential housing 23, and extends to an outside position of the tapered roller bearing 28. A circumferential groove 29 is provided at the outer side of this cylindrical portion 3a, and a claw portion 30 of a collar 30, the detailed shape of which is shown separately in FIG.
a is fitted. Claw portion 30a of this collar 30
is formed in half for easy installation.
As shown in FIG. 2, the outer diameter of the collar 30 is centered on the inner diameter of an adjuster nut 31 screwed into the differential housing 23. Furthermore, a circumferential groove 32 is provided on the outer diameter of the collar 30, and a fork 27 connected to a rod 26 is fitted into this circumferential groove 32, as shown in FIG. As a result, the operation of the piston 25 of the differential limiting cylinder device is controlled by the rod 26 and the fork 2.
7. Press the side gear 3 toward the side wall surface of the differential case 1 via the collar 30 to compress the multi-plate clutch device 4 and increase the frictional force. That is,
The right side gear 3 is operated to the right and the left side gear 3 is operated to the left to increase the differential limiting action by the multi-disc clutch device 4. In the vehicle differential limiting device configured as described above, when the operating lever 9 is pulled upward, a hydraulic pressure corresponding to the amount of movement of the operating lever 9 is generated in the master cylinder device 16. Then, this oil pressure is applied to the differential limiting cylinder device 2.
2 actuates the piston 25, presses the side gear 3 against the differential case 1 via the rod 26, fork 27, and collar 30, narrows the multi-disc clutch device 4, and limits the differential. cause the action to take place. Furthermore, this differential limiting action changes in at least three stages depending on the magnitude of the oil pressure generated by the master cylinder device 16. Therefore, on good roads that do not require differential limiting force,
By setting the operating lever 9 to the lowest position so that no hydraulic pressure is generated in the master cylinder device 16, the pressing force of the side gear 3 is weakened to the minimum, and the differential limiting action of the multi-disc clutch device 4 is hardly performed. Instead, it operates as a normal differential device (so-called normal differential). Therefore, without affecting the operability of the steering wheel,
Tire wear can also be reduced to the same level as a vehicle without a limited slip differential. Furthermore, when a strong differential limiting force is required in muddy or other road conditions with a low ground friction coefficient, the control lever 9 can be pulled up to its highest position and high hydraulic pressure can be generated in the master cylinder device 16 accordingly. , the pressing force of side gear 3 is the strongest, and the differential gear is in a locked state (so-called lock differential).
It operates as. Therefore, it becomes possible for the vehicle to escape from muddy areas and the like. Furthermore, when a predetermined differential limiting force is required on snowy roads, gravel roads, etc., the operating lever 9 is pulled up to the intermediate position, and hydraulic pressure is generated in the master cylinder device 16 in accordance with the amount of movement of the lifting operation. Depending on the oil pressure, the side gear 3 narrows the multi-plate clutch device 4 toward the differential case 1 to perform a predetermined differential limiting action (functions as a so-called limited slip differential). Therefore, even on snowy roads or gravel roads, by applying a differential limiting force suitable for the road surface conditions, it is possible to improve running performance without causing slips or spins. In this way, the differential limiting action by the multi-disc clutch device 4 of this embodiment is performed as an acting force corresponding to the magnitude of the hydraulic pressure generated by the master cylinder device 16. Since the differential limiting force is changed in at least three stages, it is possible to change the differential limiting force in at least three stages, so it is possible to change the differential limiting force in at least three stages. differential) to a powerful differential limiting device (lock differential)
The driver can easily change the differential limiting force depending on the road surface condition between the two. Therefore, it can be used in an optimal state depending on the road surface condition. Further, the differential limiting force by the multi-plate clutch device 4 is such that the position of the operating lever 9 is between the locking portion 9a and the locking piece 1.
4 are engaged with each other to determine the position, the predetermined operating position can be maintained at a constant state.
By changing the positioning mechanism of the operating lever 9, it is possible to use the differential device from a general differential device (normal differential) to a powerful differential limiting device (lock differential). In addition, a pair of left and right differential limiting cylinder devices 22
Since the left and right side gears 3 are configured to be pressed against the differential case 1, the pressing force by the differential limiting cylinder device 22 acts only on the clutch plate 6 and thrust plate 7 of the multi-plate clutch device. Therefore, other parts (taper roller bearing 28, pinion 2 and side gear 3) are not affected by the pressing load. Further, since the hydraulic operating system B including the differential limiting cylinder device 22 is configured independently outside the differential housing 23, there is no fear of pressure oil leakage or the like. Although the present invention has been described above with reference to specific embodiments, the present invention is not limited to the above-mentioned embodiments, but includes various embodiments within the scope of the claims for utility model registration. However, for example, the multi-plate clutch device 4 may be omitted and the rear surface of the side gear 3 and the side wall surface of the differential case 1 may be brought into direct frictional contact to perform the differential limiting action. Further, the master cylinder device 16 may be configured using a general-purpose hydraulic clutch master cylinder or a brake master cylinder, and the operation system A may be a foot-operated type. Furthermore, although the differential limiting cylinder device 22 is provided on the left and right sides of the differential housing 23, it is also possible to provide only one of them, and the differential limiting cylinder device 22 is provided between the left and right side gears 3. It can also be arranged and configured. In this case, the differential limiting cylinder device 2 in the embodiment described above
It becomes possible to omit the transmission member from 2 to the side gear 3.

[Effect of the idea]

As described above, according to the present invention, the differential limiting force can be changed in at least three stages depending on the magnitude of the hydraulic pressure generated by the hydraulic pressure generating device. You can freely select from a general differential device (so-called normal differential) to a powerful differential limiting device (so-called locking differential), and use it in the optimal condition according to the road surface conditions. can do. Therefore, under good road conditions, the differential limiting force can be weakened and used as a general differential (so-called normal differential), so it does not affect the operability of the steering wheel and the tire Wear can also be reduced to the same level as a vehicle not equipped with a limited slip differential. Further, in road conditions such as muddy roads where the coefficient of ground friction is low, the differential limiting force is increased to enable the vehicle to escape from muddy roads. Furthermore, even on snowy roads, gravel roads, etc., by applying a differential limiting force suitable for the road surface and performing a predetermined differential limiting action, running performance can be improved without causing slips or spins. In addition, the present invention has an operation means for changing the differential limiting force that is installed in the driver's cab of the vehicle, so it is possible to easily change the differential limiting force depending on the road surface condition while driving. have an effect.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a conventional general-purpose differential limiting device, and FIGS. 2 to 4 show a vehicle differential limiting device according to an embodiment of the present invention, and FIG. 2 is a schematic sectional view. Figures 3 and 3 are cross-sectional views showing the connected state of the differential limiting cylinder device and the collar viewed from the direction of the arrow Y in Figure 2, Figure 4 shows the collar alone, and a is a longitudinal cross-sectional view. , b are side views. Explanation of symbols: 1...Differential case, 2...Pinion, 3...Side gear, 4...Multi-plate clutch device, 9...Operation lever (operation means), 16...Master cylinder device (hydraulic pressure generator), 22 ...Differential limiting cylinder device (actuator device),
23... differential housing, 27... fork, 3
0...color.

Claims (1)

[Scope of utility model registration request] An operating means provided in the driver's cab, a hydraulic pressure generating device that generates hydraulic pressure by operating the operating means, and an actuator device that receives the hydraulic pressure generated by the hydraulic generating device and acts in a direction to press the side gear of the differential against the differential case. The differential limiting force of the differential device is changed in at least three stages by changing the pressing force of the side gear against the differential case in accordance with the hydraulic pressure generated by the hydraulic pressure generating device. A limited slip differential device for vehicles.