JP2000274513A - Pre-load type differential limiting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pre-load differential limiting device by which relatively large differential limiting initial torque can be obtained, which is excellent in lubricating performance and which improved its durability. SOLUTION: With a differential for torque-dividing and transmitting rotational driving force of a differential case 1 to left and right side gears 6, 7 arranged on the rotary shaft of the differential case, in a pre-load type differential limiting device provided with a pre-load means 10 for energizing the left and right side gears in the direction in which they move away from each other, a pair of friction providing members 8, 9 energized by the pre-load member, are arranged so as to slidably contact the tip cone surfaces 6A, 7A of the respective side gears. Thus, by wedging action between the tip cone surfaces, more firm and positive frictional force can be obtained, stable differential limiting initial torque is constantly obtained by means of aligning function of the conical surface, and the differential limiting device is supplied with lubricating oil stayed between the teeth to improve its durability.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a differential gear for transmitting the rotational driving force of a differential case to left and right side gears arranged on the rotation shaft of the differential case via differential gears meshing with each other. The present invention relates to a preload differential limiting device provided with a preload applying member for urging the left and right side gears in a direction to separate the left and right side gears.

[0002]

2. Description of the Related Art A so-called bevel type differential device in which the rotational driving force of a differential case is transmitted to a right and left side gear disposed on a rotation shaft of the differential case through a differential gear meshing with the bevel teeth. Various types of preload differential limiting devices having a preload applying member for urging the left and right side gears in the direction of separating the right and left side gears are employed. A typical example of such a device is disclosed in Japanese Patent Publication No. 51-9214 as shown in FIG. The differential gear (which is composed of left and right differential cases 21A and 21B) rotationally drives a differential gear (which is rotatably supported by a pinion shaft fixed orthogonally to a rotation shaft of a differential case (not shown)). Left and right side gears 26, 2 disposed on the rotation axis of the differential case 21 via a pinion gear and left and right side gears 26, 27 meshing with bevel teeth from both left and right sides thereof.
And a differential gear for transmitting the torque to the differential gear 7, and separating the side gears 2 from each other by the meshing reaction force of the differential gears.
6 and 27 are clutch plates 22 and 23 interposed on the back surface thereof.
Are pressed against the inner wall surfaces of the differential cases 21A, 21B to obtain a differential limiting force, and the pair of side gears 26, 27 are connected to the springs 30 via plate-shaped members 28, 29.
, So that they are biased in directions away from each other to generate an initial torque for limiting the differential.

With the differential limiting device having such a configuration,
During normal straight running, a predetermined driving force from the differential case 21 is received by the driving force from the engine, and the driving force is evenly transmitted to the left and right side gears 25 and 26 meshing with the pinion gear. At this time, the running resistance of the left and right drive wheels is substantially the same, and the pinion gears separate the side gears 25 and 26 by a meshing reaction force in a stationary state, and the clutch plate 2
A strong driving force can be obtained by integrating the differential case 21 with the differential case 21 via the second and 23. In addition, during a slight slip during traveling, an appropriate differential limiting force is obtained by the initial torque generated by the spring 30. In addition, even when the vehicle encounters a bad road such as a muddy ground and attempts to generate excessive differential action due to one-wheel idling or the like, the preload by the spring 30 exerts the meshing reaction force between the pinion gear and the side gear. And the side gears 26 and 27 are separated from each other to generate a differential limiting force between the side gears 26 and 27 and the inner wall surface of the differential case 21. The driving force is also transmitted to the low-speed wheels, and the escape performance on rough roads Can be improved.

[0004]

However, in the differential limiting device, a spring 30 as a preload applying member is provided.
Are connected to the respective side gears 26, 27 via the plate-like bodies 28, 29.
The side gears 26 and 27 are pressed in such a manner that they come into sliding contact with a portion close to the axis of the side gears. Therefore, in order to obtain a larger initial torque for limiting the differential, it is necessary to interpose a spring having a strong restoring force, which may increase the weight and size of the device. Regarding the arrangement of the plate-like bodies 28 and 29 with the spring 30 interposed therein, the position with respect to the side gears 26 and 27 is not always determined because no special centering mechanism is provided. The torque could have been constantly fluctuating. Further, the plate-like body 28 is urged by the spring 30,
29 is mainly in sliding contact with each of the side gears 26 and 27, because the opposing end faces of the side gears 26 and 27 are close to the axis of the side gears.

Accordingly, the present invention solves the problems of the preload differential limiting device of the type described above, whereby a relatively large initial torque for limiting the differential can be stably obtained even with a small size and light weight, and the lubrication performance is improved. An object of the present invention is to provide a preload differential limiting device that is excellent in durability.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention is directed to transmitting and transmitting the rotational driving force of a differential case to left and right side gears disposed on the rotational shaft of the differential case through differential gears meshing with each other. A preload differential limiting device provided with a preload applying member that urges the left and right side gears in a direction to separate the left and right side gears, wherein a pair of friction applying members urged by the preload applying member are provided. It is characterized in that the side gears are disposed so as to slide on the conical surface of the tooth tip. Further, the present invention is characterized in that the friction applying member is configured not to rotate with a side gear. Further, the present invention is characterized in that a projection having an inclined cam surface is provided on the friction imparting member, and the inclined cam surface is brought into contact with a pinion shaft or a cam shaft projecting from the pinion shaft. . Further, the present invention is characterized in that a preload applying member for urging the friction applying member is disposed at a position farthest from the rotation shaft of the differential case, and these are used as means for solving the problem. is there.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a preload differential limiting device according to the present invention will be described below with reference to the drawings. 1 and 2
FIG. 1 is an overall sectional view showing a first embodiment of a preload differential limiting device according to the present invention. A differential case 1 includes a left differential case 1A in which a differential gear is housed, and a right differential case 1B which closes the differential gear in a lid shape. And rotates by receiving a rotational driving force from a driving shaft (not shown). The differential gear includes a pinion gear 5 that meshes with the bevel teeth, and side gears 6 and 7 on both left and right sides thereof. On the inner peripheral side of the left differential case 1A, both end portions of a pinion shaft 4 which supports the pinion gear 5 and is orthogonal to the rotation axis of the differential case 1 are fixed. Left and right cone washers 2 and 3 as sliding contact members are interposed between the rear surfaces of the side gears 6 and 7 and the inner wall surfaces of the left and right differential cases 1A and 1B, respectively. The cone washers 2, 3 are provided with detent protrusions 2A, 3A extending in the axial direction, respectively, and these detent protrusions 2A, 3A are drilled on the inner wall surfaces of the left and right differential cases 1A, 1B. It is configured to be locked in the locking groove and rotate together with the differential case 1. These cone washers 2 and 3 receive the thrust force generated by the side gears 6 and 7, and the differential case 1A,
A material having a high coefficient of friction and excellent abrasion resistance is selected so as to promote fixation to the differential case when pressed against the inner wall surface of 1B.

In such a differential device, a preload applying member made up of a spring 10 is interposed between opposing surfaces of the left and right side gears 6 and 7, and a left and right friction plate made up of a pressure contact plate is provided. The application members 8, 9 are slidably disposed on the respective side gears 6, 7 to constitute a differential limiting device. The most characteristic point of the present invention is that a pair of friction applying members 8 and 9 urged by a spring or the like, which is the preload applying member 10, slidably contact the conical surfaces 6A and 7A of the side gears 6 and 7. It has been arranged to be. That is, the tip surfaces of the side gears 6 and 7 that mesh with the pinion gear 5 and the bevel teeth are formed as conical surfaces (6A and 7A), and the conical surfaces 8A and 9A are aligned with the tip surfaces. The conical surfaces 8A, 9A are formed at the corresponding portions of the left and right friction applying members 8, 9 constituted by the pressure contact plates, and the conical surfaces 8A, 9A are formed by the restoring urging force of the preload applying member 10 on the tooth conical surfaces 6A of the respective side gears 6, 7. , 7A
Is in sliding contact with Thus, a differential limiting device is formed in which the differential limiting force generated by the application of the preload is applied in addition to the meshing reaction force of the differential gear.

As shown in FIG. 2, in this embodiment,
In order to ensure that the differential limiting force is obtained, when the friction applying members 8 and 9 are in sliding contact with the side gears 6 and 7, a detent lug is provided on the outermost periphery thereof so as not to rotate with the side gears 6 and 7. 8B and 9B are extended, and these are inserted into and locked in a detent groove 1C formed in the inner peripheral surface of the left differential case 1A and fixed. FIG. 2 which is a view on arrow B in FIG. 1
As shown in FIG. 2, notches 1 and 2 are provided in some of the friction applying members 8 and 9 so as to receive the pinion gear 5 (only one of the pinion gears 5 is shown in FIG. 2) so as not to interfere therewith.
1 is engraved. A spring or the like, which is a preload applying member 10 interposed between the friction applying members 8 and 9 to generate the initial torque, is inserted and locked in the detent groove 1C on the inner peripheral surface of the left differential case 1A. Detent lug 8
It is optimal to be interposed between B and 9B. In this case, the restoring force applied by the preloading member 10 at the position farthest from the rotation axis of the differential case 1 causes the conical surfaces 6A, 7A of the side gears and the conical surfaces 8A, 9A of the friction applying members 8, 9 to be formed. And the frictional force generated between them, that is, the differential limiting force, is the largest.

In addition, the conical surfaces 6A, 7A of the side gear and the conical surfaces 8 of the friction applying members 8, 9 are provided.
The frictional force generated between A and 9A, that is, the differential limiting force, allows a stronger and more reliable frictional force to be obtained by the wedge action on the conical surface. Therefore, the preload applying member 10
The interposed position of the spring or the like is, for example, between the conical surfaces 8A and 9A (in this case, each conical surface 8A,
A spring seat substantially orthogonal to the rotation axis of the differential case 1 is provided on the opposing surface of 9A. ) May be added, or the function of the present invention can be sufficiently exhibited even at a position close to the rotation axis as in the conventional case. Further, the conical surfaces 6A, 7A of the side gears and the friction imparting members 8, 9 are provided.
By the sliding contact with the conical surfaces 8A, 9A, the friction imparting members 8, 9 are always effectively centered by the centering function of the conical surfaces. A stable initial torque for differential limitation can be always obtained without causing a positional shift due to delusion. In addition, the frictional applying member 8 slidingly pressed against the conical surfaces 6A, 7A of the side gears,
Since the conical surfaces 8A and 9A in FIG. 9 receive the supply of the lubricating oil staying between the successively rotating teeth, the conical surfaces 8A and 9A which are the sliding contact surfaces by pressing are extremely lubricated. The performance is excellent and the durability is improved.

FIG. 3 is an upper half sectional view showing a second embodiment of the preload differential limiting device according to the present invention. In this embodiment, in order to prevent the friction applying members 8 and 9 from rotating around the side gears 6 and 7, cone washers 2 and 3, which are sliding contact members fixedly fixed to the differential case 1, respectively.
Are further extended in the axial direction of the
3B, and these locking pieces 2B, 3B are locked and fixed to the outer peripheral portions of the friction applying members 8, 9. In the present embodiment, the detent lugs 8B, 9B as in the first embodiment are not required on the outer peripheral portions of the friction applying members 8, 9, and therefore, the detent grooves 1C are also provided on the differential case 1 side. There is no need to engrave, and the structure is simplified. In the present embodiment, the spring or the like (not shown) as the preload applying member 10 is provided between the conical surfaces 8A and 9A (the differential case 1).
(Via a spring seat substantially perpendicular to the rotation axis of the differential case 1) or near the rotation axis of the differential case 1.

FIG. 4 is an overall sectional view showing a third embodiment of the preload differential limiting device according to the present invention. In the present embodiment, the friction applying members 8 and 9 (not shown) are not connected to the side gears 6 and 7 in the same manner as in the second embodiment. It is not necessary to install detent lugs (8B, 9B) for the differential case 1 at 8,9. In addition, the locking and fixing portions are not provided for the cone washers 2 and 3, which are sliding members. In the present embodiment, a projection 8C having an inclined cam surface 8D is provided on the friction imparting member 8 (the same applies to 9 not shown), and the inclined cam surface 8D is protruded from the pinion shaft 4 or the pinion shaft 4. It is characterized in that it comes into contact with the camshaft 4A. Thereby, the friction imparting member 8,
9 is locked via the inclined cam surface with the pinion shaft 4 integrated with the differential case 1 so as not to rotate with the side gears 6 and 7.

Thus, in the present embodiment, the projection 8C having the inclined cam surface 8D and the pinion shaft 4 or the cam shaft 4A are almost integrated with the differential case 1 and do not rotate with the side gears 6 and 7. In addition, a sliding force of the friction applying members 8 and 9 on the side gears 6 and 7 ensures a differential limiting force due to a preload. Then, the rotational driving force from the differential case 1 is applied to the pinion shaft 4 (in the example of FIG. 4, the camshaft 4 which is disposed integrally with the pinion shaft 4 and has a circumferential phase shifted by 90 °).
A), the frictional application member 8 is separated in the axial direction by the cam action via the inclined cam surface 8D, which also causes the frictional application member 8 to move to the teeth of the side gears 6, 7. A stronger differential limiting force can be generated by strongly pressing against the conical surface. Therefore, in this embodiment, a high differential limiting force can be obtained by the reaction force due to the cam action with the pinion shaft in addition to the meshing reaction force by the differential gear and the initial torque due to the preload. In the present embodiment, when the projection 8C of the friction applying member 8 is locked to the camshaft 4A,
The projection 8C can be installed at a position relatively far from the rotation axis of the differential case 1. However, when the projection 8C of the friction applying member 8 is to be locked to the pinion shaft 4, the projection 8C Is disposed radially inward of the pinion gear 5, avoiding the pinion gear 5.

Although the embodiments of the present invention have been described above, the type of the differential gear and the type of the pinion shaft, that is, the number of the pinion gears (therefore, in this case, the shaft of the friction imparting member is included) within the scope of the present invention. The shape of the cone washer, which is a sliding contact member, the type and its form of engagement with the differential case, the shape (cross-sectional shape) of the friction imparting member, and the form of preventing its continuous rotation with the side gear That is, the form of locking and fixing to the cone washer or the differential case, the form of locking of the friction applying member with the pinion shaft with the cam action, the shape and type of the preload applying member, the form of interposition with the friction applying member, the position of interposition, etc. Can be appropriately selected.

[0015]

As described above in detail, according to the present invention, the rotational driving force of the differential case is transmitted to the left and right side gears disposed on the rotation shaft of the differential case through differential gears meshing with each other. In a differential device for distributing and transmitting, in a preload differential limiting device provided with a preload applying member for urging in a direction to separate the left and right side gears, a pair of biased by the preload applying member is provided. By arranging the friction applying member so as to be in sliding contact with the conical surface of the tip of each of the side gears, a stronger and more reliable frictional force is achieved by the wedge action between the conical surface of the tip of the side gear and the conical surface of the friction applying member. Therefore, a sufficient differential limiting force can be obtained regardless of the position where the preload applying member is interposed. In addition, the side gear and the friction imparting member are always centered effectively by the centering function of the conical surface, so that a stable initial torque for differential limitation is always obtained. In addition, the conical surface of the friction applying member receives the supply of the lubricating oil stagnating between the teeth of the side gear that rotates one after another, so that the conical surface is excellent in lubrication performance and durability is improved.

Further, since the friction applying member is configured not to rotate with the side gear, a sufficient frictional force can be obtained between the friction applying member and the side gear, so that a reliable differential limiting force can be obtained. It becomes possible. Further, a projection having an inclined cam surface is provided on the friction applying member, and the inclined cam surface is brought into contact with a pinion shaft or a cam shaft projecting from the pinion shaft. When transmitted to a shaft or the like, the cam action via the inclined cam surface separates the friction imparting member in the axial direction and strongly presses the friction imparting member against the conical surface of the tip of the side gear to provide a stronger differential. A limiting force can be generated. Therefore, in addition to the meshing reaction force by the differential gear and the initial torque by the preload, a high differential limiting force due to the reaction force by the cam action between the pinion shaft is obtained. Further, when the preload applying member for urging the friction applying member is disposed at a position farthest from the rotation axis of the differential case, even if the preload applying member is relatively small and has a small capacity, the rotation axis of the differential case can be reduced. A large differential limiting force can be obtained by the biasing of the restoring force by the preload applying member at the position farthest from the vehicle. As described above, according to the present invention, there is provided a preload-type differential limiting device in which a relatively large initial torque for limiting the differential can be stably obtained even with a small size and light weight, and the lubricating performance is improved and the durability is improved. Is done.

[Brief description of the drawings]

FIG. 1 is an overall sectional view showing a first embodiment of a preload differential limiting device according to the present invention.

FIG. 2 is a view showing a first embodiment of a preload differential limiting device according to the present invention, and is a view taken in the direction of arrow B in FIG. 1;

FIG. 3 is an upper half sectional view showing a second embodiment of the preload differential limiting device according to the present invention.

FIG. 4 is an overall sectional view showing a third embodiment of a preload differential limiting device according to the present invention.

FIG. 5 is an overall sectional view of a conventional preload differential limiting device.

[Explanation of symbols]

 Reference Signs List 1 differential case 1A left differential case 1B right differential case 1C detent groove 2 left sliding contact member (cone washer) 2A detent protrusion 2B engaging piece 3 right sliding contact member (cone washer) 3A detent protrusion 3B engaging piece 4 pinion Shaft 4A Camshaft 5 Pinion gear 6 Left side gear 6A Tooth surface 7 Right side gear 7A Tooth surface 8 Left friction applying member (pressure contact plate) 8A Conical surface 8B Stop lug 8C Projection 8D Inclined cam surface 9 Right friction applying member (Press contact) Plate) 9A conical surface 9B locking lug 10 preload applying member (spring) 11 notch

Claims (4)

[Claims] 1. A differential device for transmitting a torque of a differential case by distributing torque to left and right side gears disposed on a rotation shaft of the differential case via differential gears meshing with each other in a beveled manner. In a preload differential limiting device provided with a preload applying member that urges the left and right side gears in a direction to separate the left and right side gears, a pair of friction applying members urged by the preload applying member are attached to the conical surface of the tip of each of the side gears. A preload-type differential limiting device, which is arranged to be in sliding contact. 2. The preload differential limiting device according to claim 1, wherein the friction applying member is configured not to rotate around the side gear. 3. The friction imparting member is provided with a projection having an inclined cam surface, and the inclined cam surface is brought into contact with a pinion shaft or a cam shaft protruding from the pinion shaft. Or the preload differential limiting device according to 2. 4. The preload differential according to claim 1, wherein a preload applying member for urging the friction applying member is disposed at a position farthest from a rotation shaft of the differential case. Limiting device.