JPH0311061Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to automatic differential mechanisms used in vehicles.

BACKGROUND TECHNOLOGY Vehicles such as automobiles are generally equipped with a differential device.
This differential device is equipped with a differential limiting device to provide smooth steering when turning and reduce turning resistance, and to ensure driving force without slipping at other times. . Conventional differential limiting devices generally include a no-slip differential, a no-spin differential, a deflock, and the like.

Among these, the no-slip differential device has a friction clutch installed between the differential case and the left and right axles, or side gears.
When a differential occurs due to slip or the like, the friction torque in the friction clutch increases the torque transmitted to the low-speed axle.

The no-spin differential device uses a dog clutch instead of gears, and when turning, the clutch on the high-speed side axle is released so that power is transmitted only to the low-speed side.

A differential lock device uses a lever or the like to forcibly connect one axle and a differential case by external force, and some devices also enable automatic locking and unlocking by interlocking with the steering wheel.

Problems to be Solved by the Invention However, with the no-slip differential device, there is a problem that some brake loss occurs during turning due to the action of the friction clutch, resulting in resistance and driving force loss. Further, in the no-spin differential device, since no power is transmitted to the high-speed side, only the inner wheel of the turn contributes to the drive during a turn, resulting in a problem in that the driving force decreases. Furthermore, the defrock device has the problem of not being able to prevent slippage during unlocking.

SUMMARY OF THE INVENTION It is an object of the present invention to eliminate all of the problems in the conventional devices described above, to reduce the reduction in driving force due to brake loss during turning, and to prevent the occurrence of slips.

Means for Solving the Problems In order to achieve the above-mentioned object, the present invention has the following features: A first wheel fitted onto either the left or right axle so as to be slidable in the axial direction and rotatable integrally with the axle.
a cam sleeve; a spring that urges the first cam sleeve toward the differential case; and a spring that urges the first cam sleeve toward the differential case; a second cam sleeve that is fitted onto the outside of the differential case and is formed with a locking pawl that engages with the end surface of the differential case; The first cam sleeve and the differential case have circumferentially inclined surfaces formed therein, and these inclined surfaces are brought into contact with each other by the biasing force of the spring, thereby allowing the first cam sleeve and the differential case to rotate together, and also allowing the vehicle to turn. When the axle torque is generated based on the turning moment acting on the inclined surfaces, the inclined surfaces are released from contact with each other against the biasing force of the spring, and the first cam sleeve and the differential case are disengaged. It has a cam mechanism for releasing it.

With this structure, the cam sleeve and the differential case are connected to each other and the differential case is locked when the vehicle is moving straight, and the differential mechanism functions reliably when the vehicle is turning. If a slip occurs during turning, the reaction force from the ground disappears on the slip side, so the cam sleeve and the differential case are connected again by the biasing force of the spring, returning to the differential case. Further, since a second cam sleeve was provided between the first cam sleeve and the differential case, and a cam mechanism was provided between the first cam sleeve and the second cam sleeve, this second cam sleeve was provided between the first cam sleeve and the differential case. The lock pawl formed on the cam sleeve can be made to match the pawl of the differential case regardless of the cam mechanism, so that a conventional differential device for a differential lock can be used as is. become. As a result, the cam mechanism can be made highly flexible.

Embodiment In FIG. 1, 1 is one axle, 2 is the other axle, and 3 is a differential device. In the differential device 3, 4 is a pinion on the drive shaft 5 side, and 6 is a ring gear that meshes with this pinion 4. The ring gear 6 is attached to the differential case 8 via a spline portion 7 so as to be able to rotate integrally therewith. The differential case 8 has bearings 9,
It is rotatably supported by an axle case 11 via a shaft 10. Inside differential case 8,
A pair of pinions 13 are rotatably supported by the shaft 12. At the tips of the axles 1, 2, side gears 16,
17 are attached so as to be rotatable together, and these side gears 16 and 17 are meshed with the pinion 13. 18 is the axle 1, 2 and the side gear 16,
This is a stopper that comes into contact with the tip of 17 to regulate its position.

A sleeve 19 serving as a stopper is fitted onto a portion of the axle 1 following the side gear 16. The sleeve 19 is fitted onto the spline portion 14 such that one end thereof contacts the end surface of the side gear 16 and is rotatable relative to the axle 1 . A second cam sleeve 20 is further fitted onto the sleeve 19. Bearings 21 and 22 rotatably support the cam sleeve 20 on the axle case 11. An annular projection 23 is formed on the cam sleeve 20, and the projection 23 is
a bearing 21 that is locked to the axle case 11;
The position of the cam sleeve 20 in the axial direction of the axle 1 is regulated by sandwiching it between the cam sleeve 20 and a bearing 22 that is secured to the differential case 8 via the bearing 9. A spacer ring 24 is interposed between the bearings 21 and 22 in correspondence with the projection 23.

On the end surface of the differential case 8, there is a third
A plurality of lock pawls 25 are formed in the circumferential direction as shown in the figure, and these lock pawls 25 are formed for use in the conventional deflock device described above. A similar lock pawl 26 is also formed on the end surface of the second cam sleeve 20, and both lock pawls 25 and 26 are engaged with each other. Therefore, as described above, since the position of the cam sleeve 20 is restricted in the axial direction of the axle 1, the engagement between the lock pawls 25 and 26 is never released, and the cam sleeve 20 is constantly It will rotate together with the financial case 8.

A first cam sleeve 27 is fitted onto a portion of the axle 1 that follows the second cam sleeve 20 .
That is, the spline portion 14 of the axle 1
The first cam sleeve 27 includes a cam sleeve main body 28 spline-fitted to the axle 1;
A bearing housing 29 disposed outside the cam sleeve body 28, and a bearing housing 29 disposed outside the cam sleeve body 28;
A bearing 30 is rotatably supported within a bearing housing 29.

A cam mechanism 31 is formed at the ends of the first and second cam sleeves 27 and 20 that face each other. That is, as shown in FIG. 4, at the end of the second cam sleeve 20, protrusions 33 having circumferentially inclined surfaces 32 are formed at intervals of 180 degrees in the circumferential direction. Further, a protrusion 34 corresponding to the protrusion 33 is formed on the cam sleeve main body 28, and an inclined surface 35 that can come into contact with the inclined surface 32 is formed on this protrusion 34. 36 and 37 are valleys.

The sleeve 19 passes inside the cam mechanism 31, and its tip 38 is in contact with the trough 37 of the cam sleeve body 28. That is, this restricts the position of the cam sleeve main body 28, and the protrusion 33 and the trough 37, or the protrusion 34 and the trough 36 are spaced apart from each other so that they do not come into contact with each other.

The first cam sleeve 27 is movable in the axial direction of the axle 1 along the spline portion 14 by the action of the fork 39 . That is, the second
As shown in the figure, 40 has both ends connected to the axle case 11.
A collar 41 is spline-fitted to the shaft 40. A pair of fork arms 42 sandwiching the bearing housing 29 are fixed to the collar 41, and a fork pin 44 that engages with an annular groove 43 formed in the bearing housing 29 is fixed to the tip of each fork arm 42. There is.

One end of the shaft 40 protrudes from the axle case 11, and a fork lever 46 is spline-fitted to this protrusion 45. One end of a tension coil spring 47 disposed outside the axle case 11 is hung on the fork lever 46, and this spring 47 moves the first cam sleeve 27 through the fork 39 to the differential case. It is biased towards the 8 side. The other end of the spring 47 is hung on a bracket 48, and the bracket 48 can be moved in the length direction of the spring 47 to adjust the spring force.

In such a configuration, in normal cases such as when traveling straight, the first cam sleeve 27 is moved toward the differential case 8, that is, the second cam sleeve 27 due to the action of the spring 47.
is biased toward the cam sleeve 20 side, and the cam mechanism 31
The inclined surfaces 32 and 35 of the protrusions 33 and 34 abut each other. As a result, the rotational force from the differential case 8 is transmitted to the axle 1 via the second and first cam sleeves 20 and 27. As a result, the vehicle is in a deflocked state, providing stable driving performance.

When turning, a relative movement occurs between the differential case 8 and the axle 1. For example, when the axle 1 is placed on the inner side of the turning, the moment generated by the frictional force between the tires and the ground The sum of the turning torque caused by this and the load torque caused by the running resistance of the wheels acts on the first cam sleeve 27.
On the other hand, a driving torque in the opposite direction is applied to the differential case 8, which is the sum of the left and right axle torques. When the sum of the swing torque and the load torque exceeds a certain value, the inclined surfaces 32, 35 resist the force of the spring 47.
Slippage occurs between the first cam sleeve 27 and the first cam sleeve 27.
is displaced in the direction of being removed from the second cam sleeve 20, and the engagement between the protrusions 33 and 34 is released. As a result, unlocking is achieved and the differential device 3 becomes functional, allowing smooth turning.

At this time, the cam sleeve main body 28 of the first cam sleeve 27 is locked to the sleeve 19, and the protrusion 3
Since the protrusions 3 and 34 are in contact with each other only in the vicinity of their tops, when the vehicle is turning, the protrusions 33 and 34 only slightly slip until they cross over each other. As a result, the protrusions 33, 34
wear is suppressed, and at the same time, the generation of wear debris is also significantly reduced. Furthermore, since the protrusions 33 and 34 are formed at a distance in the circumferential direction, once they are disengaged, they will not be re-engaged for a while, which can reduce turning drive resistance. It becomes possible. The degree of engagement between the protrusions 33 and 34 can be adjusted by changing the length of the sleeve 19 and changing the position of the cam sleeve body 28.

The sum of the turning torque and the load torque when the protrusions 33 and 34 are disengaged depends on the force of the spring 47 and the inclined surfaces 32 and 35, depending on the state of the running surface.
It can be adjusted by adjusting the inclination angle. The force of spring 47 is applied by changing the position of bracket 48.
This adjustment can be made easily by changing the length of the spring 47 and the bracket 48, since the spring 47 and the bracket 48 are provided outside the axle case 11.

When a slip occurs during a turn, the load from the ground becomes smaller, and the axle torque at this time becomes smaller than when no slip occurs. Therefore, the force of the spring 47 overcomes the axle torque, and the protrusion 3
3 and 34 engage with each other. This returns the vehicle to the defroc state again, so that the slip is quickly contained.

A second cam sleeve 20 is provided between the first cam sleeve 27 and the differential case 8, a cam mechanism 31 is formed between both cam sleeves 27, 20, and the second cam sleeve 20 and differential case 8 are locking claws 25,2
6, the above-mentioned conventional differential device for a differential lock can be used as is, making it possible to create an inexpensive and flexible mechanism. That is, even if the conventional differential device described above is used, the cam mechanism 31 can have any shape, so there is no restriction, and the cam mechanism 31, which tends to generate wear particles, can be kept away from the bearing 21. The invented automatic differential mechanism can be easily installed as an additional device on a conventional differential vehicle.

Effects of the invention As described above, according to the invention, when the vehicle is traveling straight, the differential lock is applied, so no slip occurs and driving force is secured, and when turning, the differential mechanism functions reliably. This enables smooth steering and prevents excessive brake loss and reduction in driving force. Furthermore, even if a slip occurs when the vehicle is unlocked, such as when turning, the vehicle is quickly returned to the defrocked state, and this slip can be eliminated immediately. Furthermore, since the cam mechanism is provided between the first cam sleeve and the second cam sleeve, the lock pawl formed on the second cam sleeve is independent of the cam mechanism. It can be made to match the claws of the case, and therefore, a conventional differential device for a defrock can be used as is. As a result, it becomes possible to provide an inexpensive and flexible mechanism. In other words, the cam mechanism can be shaped into any shape, so there are no restrictions, and the cam mechanism, which tends to produce wear particles, can be moved away from the bearings.The automatic differential mechanism of the present invention can also be added to conventional differential vehicles. It can be easily installed as

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of an embodiment of the present invention, FIG. 2 is a cross-sectional view taken from FIG. 1, FIG. 3 is a developed view of the lock pawl, and FIG. 4 is a developed view of the cam mechanism. 1...Axle, 8...Differential case, 20...Second cam sleeve, 25, 26...
... Lock pawl, 27 ... First cam sleeve, 31
...Cam mechanism, 32, 35...Slanted surface, 47...
Spring.

Claims (1)

[Scope of Claim for Utility Model Registration] A first device fitted onto either the left or right axle so as to be slidable in the axial direction and rotatable integrally with the axle.
a cam sleeve; a spring that biases the first cam sleeve toward the differential case; and a spring that urges the first cam sleeve toward the differential case; a second cam sleeve that is fitted onto the outside of the differential case and is formed with a locking pawl that engages with the end surface of the differential case; The first cam sleeve and the differential case have circumferentially inclined surfaces formed therein, and these inclined surfaces are brought into contact with each other by the biasing force of the spring to enable the first cam sleeve and the differential case to rotate together, and also to prevent the vehicle from turning. When the axle torque is generated due to the turning moment acting on the inclined surfaces, the inclined surfaces are released from contact with each other against the biasing force of the spring, and the first cam sleeve and the differential case are disengaged. An automatic differential mechanism comprising: a cam mechanism for releasing the differential; and a cam mechanism for releasing the differential.