JPH09112657A - Differential device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To generate a large torque distribution ratio and prevent a pinion from tumbling. SOLUTION: A differential device of present invention comprises a differential case 37 rotated by an engine, supporting holes formed in the case wall, pinion gears 49 supported by the holes with possibility of sliding and rotating, a sun gear 55 on the output side meshing with the pinions 49, and an internal gear 53 on the output side meshing with the pinions 49, wherein the meshing part 83 of the pinions 49 with the sun gear 55 is overlapped in radial direction on the meshing part 85 of the pinions 49 with the internal gear 53.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a differential device used for a vehicle.

[0002]

2. Description of the Related Art U.S. Pat. S. Patent 3792628
The differential device 201 as shown in FIG.
Is disclosed in FIG. 1 in DE 3906650 A1.
A differential device 203 such as No. 3 is described.

These differential devices 201, 2
Reference numeral 03 is used for a center differential (a differential device that distributes the driving force of the engine to the front wheels and the rear wheels) of a four-wheel drive vehicle, etc., and is a case member connected to the differential cases 205 and 207 and the differential case 207 by a pin 206, respectively. Two
08 and a supporting member 20 formed by a case member 212 connected to the differential case 205 by a spline portion 210.
9, a plurality of pinion gears 213 and 215 rotatably supported by the respective pinion gears 213 and 215.
The output side sun gears 217 and 219 meshing with the pinion gears 213 and 215 on the radially inner side of each of the pinion gears 2
The pinion gears 213, 21 on the outer side in the radial direction of 13, 215
5, the internal gears 221, 22 on the output side that mesh with 5
It is composed of 3 etc.

Internal gears 221 and 2 having a large number of teeth
23 is a sun gear 21 connected to the rear wheel side and having a small number of teeth.
7, 219 are connected to the front wheel side.

The driving force of the engine for rotating the differential cases 205 and 207 is from the pinion gears 213 and 215 to the sun gears 217 and 219 and the internal gears 221 and 22.
3 is transmitted to the front wheels and the rear wheels, and when a driving resistance difference occurs between the front and rear wheels, the driving force is differentially distributed to the front and rear wheels by the rotation of the pinion gears 213 and 215.

At this time, the internal gears 221, 22
3 and the sun gears 217 and 219, the large and small driving torques are sent to the rear wheel side and the front wheel side, respectively, so that a torque distribution characteristic suitable as a center differential is obtained. Further, this torque distribution ratio obtains a large value by using an internal gear and a sun gear as the output gear.

Further, during transmission of torque, the sun gear 21
The pinion gear 21 is caused by the reaction force of engagement with 7, 219.
A torque-sensitive differential limiting force is obtained by the frictional resistance generated by pressing 3, 215 against the support holes 209, 211 and the frictional resistance generated at the meshing portion of each gear.

[0008]

However, the respective pinion gears 213 and 215 are engaged with each other by the engagement of the internal gears 221 and 223 with the sun gears 217 and 219.
As indicated by the arrows 2 and 13, the meshing reaction force in the opposite direction is received at different positions in the tooth width direction.

Therefore, the pinion gears 213 and 215 are tilted with respect to the normal rotation axis direction, and the support holes 209 and
Uneven wear and seizure occur between the gears 211, and the pinion gears 213 and 215 fall down, resulting in poor tooth contact of each gear, resulting in deterioration of gear strength and durability.

Therefore, an object of the present invention is to provide a differential device capable of obtaining a large torque distribution ratio and preventing the pinion gear from falling.

[0011]

According to another aspect of the present invention, there is provided a differential device including: a differential case which is rotationally driven by a driving force of an engine; a support hole formed in the differential case; A plurality of pinion gears, an output-side sun gear that meshes with these pinion gears inside each pinion gear, and an output-side internal gear that meshes with these pinion gears outside each pinion gear. It is characterized in that the meshing portion, the meshing portion of each pinion gear, and the internal gear overlap in the radial direction.

The driving force of the engine for rotating the differential case is distributed from the support hole of the differential case to the sun gear and the internal gear via the pinion gear. At this time, a large driving torque is sent to the wheels on the internal gear side having a large number of teeth, and a smaller driving torque is sent to the wheels on the sun gear side having a small number of teeth, so that an unequal torque distribution characteristic is obtained. .

This torque distribution ratio has a large value by using an external gear sun gear and an internal gear internal gear as output gears.

Further, during transmission of torque, a torque-sensitive differential limiting force is obtained by the frictional resistance generated when the pinion gear is pressed against the support hole by the meshing reaction force and the frictional resistance generated at the meshing portion of each gear. .

Further, since the meshing portion between each pinion gear and the sun gear and the meshing portion between each pinion gear and the internal gear are overlapped in the radial direction (direction of meshing reaction force), unlike the conventional example. The meshing reaction forces in the opposite directions input from the sun gear and the internal gear are canceled by this overlapping portion, and the tilting torque that tends to tilt each pinion gear from the regular rotation shaft is reduced.

Therefore, the pinion gears do not fall down, uneven wear and seizure between the pinion gears and the support holes are prevented, and the meshed state of the gears is maintained well.
The strength and durability of each gear are improved.

According to a second aspect of the present invention, the differential device is formed by one member having a driving force input portion and a pinion gear support hole, and a large torque distribution ratio is obtained as in the differential device of the first aspect. At the same time, the meshing reaction force from the sun gear and the internal gear is canceled by the overlapping part to prevent the pinion gears from collapsing, so uneven wear and seizure between the pinion gears and the support holes are prevented, and the teeth of each gear are prevented. Good hits are maintained and strength and durability are improved.

In addition to this, since the differential case is composed of one member, the number of parts is small, the processing cost is reduced, and each gear is composed of a plurality of members and supported by different members. Unlike the two- or three-part differential case, it is not affected by the processing accuracy of each component or the error during assembly. Therefore, the supporting state of each gear, especially the pinion gear, is improved, uneven wear and seizure are prevented, durability is improved, and the normal function of the differential device is maintained for a long time.

The differential device according to a third aspect of the present invention is such that the support hole is provided with a full-circumference support portion that supports the entire circumference of the pinion gear, and a large torque distribution ratio can be obtained as in the differential device of the first or second aspect. At the same time, uneven wear and seizure between the pinion gear and the support hole due to the tilting of the pinion gear are prevented, the tooth contact of each gear is kept good, and the strength and durability are improved.

In addition to this, by providing the support hole with a full-circumference support portion for supporting the entire circumference of the pinion gear, the support state of the pinion gear is further improved, and the effect of preventing uneven wear and seizure between the pinion gear and the support hole is provided. And the tooth contact improvement effect of each gear is further improved.

According to a fourth aspect of the present invention, in the differential device, an extension support portion for supporting the pinion gear is provided in a support hole of the pinion gear at a portion where a meshing portion with the sun gear and a meshing portion with the internal gear overlap each other. Similar to the differential device according to any one of claims 1 to 3, a large torque distribution ratio is obtained, uneven wear and seizure between the pinion gear and the support hole due to tilting of the pinion gear are prevented, and the tooth contact of each gear is improved. The strength and the durability are improved by being kept.

In addition to this, the support hole is extended in a space other than each meshing portion of the overlap portion, and the extension support portion for supporting the pinion gear is provided, so that the support width of the pinion gear due to the support hole is corresponding to the tooth width direction. Becomes wider. Therefore, the width of the transmission portion that transmits the rotational driving force of the differential case to the pinion gear is widened only by this extension support portion, and the driving force can be transmitted by using the tooth width of the pinion gear widely, so that the support hole is not deformed when transmitting torque. Reduce. Further, the effect of preventing the pinion gear from falling and the effect of preventing uneven wear and seizure are further improved.

According to a fifth aspect of the present invention, in the differential device, the differential case has a casing main body having a support wall for the pinion gear between one end surface of the pinion gear and the flange portion of the internal gear, and a support wall for the other end surface of the pinion gear. As with the differential device according to any one of claims 1 to 4, a large torque distribution ratio is obtained, and uneven wear and seizure between the pinion gear and the support hole due to tilting of the pinion gear are prevented. As a result, the tooth contact of each gear is kept good, and the strength and durability are improved.

In addition to this, the support hole supports the entire tooth width of the pinion gear, and the support hole is formed in the casing body to obtain sufficient strength, so that a stable support state of the pinion gear is obtained and the torque is improved. The support hole is not deformed during transmission, and the effect of preventing the pinion gear from falling and the effect of preventing uneven wear and seizure are further improved.

According to a sixth aspect of the present invention, in the differential apparatus, the pinion gear is provided with a sliding support portion supported by the support hole, in addition to the gear portion that meshes with the sun gear and the internal gear. Similar to either of the differential gears, a large torque distribution ratio can be obtained, and uneven wear and seizure between the pinion gear and the support hole due to tilting of the pinion gear are prevented, good tooth contact of each gear is maintained, and strength and durability are maintained. The sex is improved.

Further, in addition to the gear portion, the slide support portion supported by the support hole is provided in the pinion gear, so that the surface pressure between the gear portion and the support hole and the surface pressure between the slide support portion and the support hole are increased. Respectively, the effect of preventing uneven wear and seizure between the pinion gear and the support hole is further improved, and the effect of preventing the pinion gear from falling is further improved.

In the differential device according to claim 7, each gear is composed of a helical gear. As with the differential device according to any one of claims 1 to 6, a large torque distribution ratio can be obtained and the pinion gear is tilted. Uneven wear and seizure between the pinion gear and the support hole are prevented, the tooth contact of each gear is kept good, and the strength and durability are improved.

In addition to this, the mesh thrust force of the helical gear causes frictional resistance at the end face of the gear, and the torque sensitive differential limiting function is enhanced.

In the differential device according to the eighth aspect of the present invention, the sun gear is formed hollow, and the one-side output shaft between the front and rear wheel differentials between the axles penetrates the sun gear. Similar to either differential device, a large torque distribution ratio is obtained, uneven wear and seizure between the pinion gear and the support hole due to tilting of the pinion gear is prevented, good tooth contact of each gear is maintained, and strength and durability are maintained. And improve.

In addition to this, by penetrating the output shaft of the inter-axle differential to the hollow sun gear, coaxial arrangement with the inter-axle differential is possible, and the coaxial arrangement allows the traction system of a four-wheel drive vehicle. Becomes compact.

According to a ninth aspect of the present invention, in the differential device, the drive force input portion of the differential case is arranged on one side in the axial direction, and the output shafts of the sun gear and the internal gear are arranged on the other side in the axial direction. The system is established and claim 1
Like the differential device of any one of
A large torque distribution ratio can be obtained, uneven wear and seizure between the pinion gear and the support hole due to tilting of the pinion gear can be prevented, and the tooth contact of each gear can be maintained well and strength and durability can be improved.

[0032]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will be described with reference to FIGS. This embodiment comprises the features of claims 1, 2, 3, 4, 6, 7, 8, 9.
FIG. 1 shows a differential device of this embodiment. FIG. 11 shows a power system of a four-wheel drive vehicle using each embodiment.
The left and right directions are the left and right directions of this vehicle and in FIG. 1, and members and the like without reference numerals are not shown.

As shown in FIG. 11, this power system is arranged inside the engine 1, the transmission 3, the center differential 7 (the differential device of FIG. 1) constituting the transfer 5, the direction changing mechanism 9, and the transfer case 11. Front differential 13 (differential device for distributing driving force to the left and right front wheels: axle differential), front axle 15, 1
7, left and right front wheels 19, 21, propeller shaft 23, direction changing mechanism 25, rear differential 27 (differential device for distributing driving force to the left and right rear wheels), rear axles 29, 31,
It is composed of left and right rear wheels 33, 35 and the like.

The driving force of the engine 1 is distributed from the transmission 3 through the center differential 7, and is directly transmitted to the front differential 13 on the front wheel side, and the direction changing mechanism 9, the propeller shaft 23, and the direction changing mechanism on the rear wheel side. 25 and transmitted to the rear differential 27. The transmitted driving force is
The front differential 13 distributes the left and right front wheels 19 and 21, and the rear differential 27 distributes the left and right rear wheels 33 and 35.

As shown in FIG. 1, a casing member 39 is fixed to the differential case 37 of the center differential 7 with bolts 41. A bolt hole 44 for fixing the ring gear 43 (FIG. 11) is provided in the left end portion (one side in the axial direction) of the casing member 39, and a hole 45 (driving force input portion) for this bolt is provided in the differential case 37. Has been. Ring gear 4
3 meshes with the output gear 47 (FIG. 11) of the transmission 3, and thus the differential case 37 and the casing member 39 are rotationally driven by the driving force of the engine 1.

The differential case 37 is supported by the transfer case 11 via a bearing 48, and the transfer case 11 is provided with an oil reservoir. This oil is repelled by a rotating member inside the transfer case 11, such as the center differential 7 and the direction changing mechanism 9.

As shown in FIG. 2, four helical pinion gears 49 are arranged in the differential case 37 at equal intervals in the circumferential direction. As shown in FIG. 3, the differential case 37 has the support holes 5
1 is formed, and as shown in FIGS. 1 and 2, the pinion gear 49 is slidably supported.

Further, the differential case 37 and the casing member 39
An internal gear 53 and a sun gear 55, each of which is a helical gear, are arranged inside the.

The internal gear 53 includes a flange portion 57 and a hub portion 59 (output shaft on the rear wheel side), and is rotatably supported by the hub portion 59 on the inner circumference of the casing member 39. The hub portion 59 penetrates from the right end side (the other side in the axial direction) of the casing member 39 to the outside, and a spline portion 61 for connecting to the rear wheel side is provided at the right end portion thereof. The outer peripheral surface of the internal gear 53 is slidably rotatably supported by a sliding surface 63 provided on the inner periphery of the casing member 39, and the flange portion 57 and the casing member 39.
A thrust washer 65 is arranged between the and.

The sun gear 55 is formed hollow and is rotatably supported by the left hub portion 67 on the inner periphery of the differential case 37.
The right hub portion 69 (the output shaft on the front wheel side) is rotatably supported on the inner periphery of the hub portion 59 of the internal gear 53. A spline portion 71 for connecting to the front wheel side is provided at the right end of the hub portion 69. Thrust washers 73 and 75 are arranged between the sun gear 55 and the differential case 37 and the flange portion 57 of the internal gear 53, respectively.

As shown in FIG. 1, each pinion gear 49 is composed of a sliding support portion 77 and a gear portion 79 which are integrally formed, and is slidably and rotatably supported in a support hole 51 of the differential case 37. The gear portion 79 has a sun gear 55 on the radially inner side.
And meshes with the internal gear 53 on the radially outer side. The left and right end surfaces of each pinion gear 49 face the differential case 37 and the flange portion 57 of the internal gear 53, respectively.

A right end portion 81 of the sun gear 55, a meshing portion 83 of each pinion gear 49, and a meshing portion 85 of each pinion gear 49 and the internal gear 53 are indicated by arrows 8 in FIG.
In the range of 7, they overlap in the radial direction.

As shown in FIG. 3, the support hole 5 of the differential case 37 is formed.
Reference numeral 1 supports a full-circumference support portion 89 that supports the sliding support portion 77 of each pinion gear 49 over the entire circumference, and an overlap portion 91 in which each pinion gear 49 overlaps the sun gear 55 and the internal gear 53 and meshes with each other. And an extended support portion 93 for

Further, as shown in FIG. 1, the outer peripheral portion 9 of the support hole 51 is
The width 97 of 5 is wider than the half tooth width 99 of each pinion gear 49. The left end portion 101 of the sun gear 55 faces the outer peripheral portion 95 in the radial direction.

As shown in FIG. 11, the internal gear 5
The hub portion 59 of No. 3 is spline-connected to the transmission gear 103 side of the gear transmission mechanism 107 including the transmission gears 103 and 105, and is connected to the rear wheel side via the direction changing mechanism 9.

Further, the hub portion 69 of the sun gear 55 is spline-connected to the differential case 109 side of the front differential 13, and the left axle 15 of the front differential 13 (one-side output shaft).
Penetrates the hub portions 67 and 69 of the sun gear 55.

The driving force of the engine 1 for rotating the differential case 37 and the casing member 39 is generated by each pinion gear 49.
Is distributed to the rear wheel side and the front wheel side via the internal gear 53 and the sun gear 55. At this time, a large driving torque is sent to the rear wheels 33, 35 of the internal gear 53 side having a large number of teeth, and a smaller driving torque is sent to the front wheels 19, 21 of the sun gear 55 side having a small number of teeth. The optimal torque unequal distribution characteristics for the center differential can be obtained.

Further, for example, when a driving resistance difference occurs between the front wheels and the rear wheels during traveling on a rough road, the driving force of the engine 1 is differentially distributed to the front and rear sides by the rotation of each pinion gear 49.

During transmission of torque, frictional resistance is generated at the meshing portion of each gear.

Further, the outer circumference of each pinion gear 49 is supported by the supporting hole 5 of the differential case 37 due to the reaction force of engagement with the sun gear 55.
When it is pressed against 1, frictional resistance is generated. Along with that, the internal gear 53 is pressed against the sliding surface 63 of the casing member 39 by the reaction force of meshing with each pinion gear 49, and frictional resistance is generated.

Further, due to the meshing thrust force of the helical gear, both the end faces of each pinion gear 49 and the differential case 37.
Also, frictional resistance is generated between the internal gear 53 and the flange portion 57 of the internal gear 53, and frictional resistance is generated between the sun gear 55 and the differential case 37 and the flange portion 57 via the thrust washers 73 and 75, and the thrust washer 65 is Through this, frictional resistance is generated between the flange portion 57 and the casing member 39.

Due to these frictional resistances, a torque sensitive differential limiting function can be obtained.

As shown in FIG. 1, the opening 1 is formed in the differential case 37.
11, the casing member 39 is provided with an opening 113, and the internal gear 53 is provided with an opening 115. The oil splashed from the oil sump of the transfer case 11 has these openings 111, 113,
115 flows into the differential case 37, the casing member 39, and the internal gear 53, and is supplied to the meshing portions of the gears and the sliding portions that generate a torque-sensitive differential limiting force to sufficiently lubricate them. .

In this way, the center differential 7 is constructed.

As described above, in the center differential 7, a large torque distribution ratio is obtained by using the external gear sun gear 55 and the internal gear internal gear 53 as the output gears.

In addition to this, the meshing portion 83 of the pinion gear 49 and the sun gear 55 and the meshing portion 85 of the pinion gear 49 and the internal gear 53 are arranged in the radial direction (the meshing reaction force is indicated by the arrow 87 in FIG. 1). Direction), the sun gear 55 is different from the conventional example.
The meshing reaction force in the opposite direction input from the internal gear 53 is canceled by the overlap portion 91 of the pinion gear 49. Therefore, the tilting torque for tilting each pinion gear 49 from the regular rotation shaft is reduced accordingly.

Therefore, the pinion gears 49 do not fall down, uneven wear and seizure between the pinion gears 49 and the support holes 51 are prevented, and the respective gears are kept in good tooth contact for strength and durability. The sex is improved.

Also, the meshing reaction force input from the left end 101 of the sun gear 55 to the pinion gear 49 is received by the outer peripheral portion 95 of the support hole 51, so that the force applied to the pinion gear 49 is dispersed that much, which is advantageous in terms of strength and the pinion gear 4
The durability of 9 is improved.

Further, since the supporting hole 51 is provided with the entire circumference supporting portion 89 for supporting the entire circumference of the pinion gear 49, the supporting state of the pinion gear 49 is further improved, and the pinion gear 4
The effect of preventing uneven wear and seizure between the gear 9 and the support hole 51 and the effect of improving the tooth contact of each gear are improved accordingly.

Further, the support hole 51 is extended to the overlap portion 91 by utilizing the space other than the meshing portions 83 and 85, and the extension support portion 93 for supporting the pinion gear 49 is provided. The support width of 49 becomes wider in the tooth width direction. Therefore, the width of the transmission portion that transmits the rotational driving force of the differential case 37 to the pinion gear 49 is widened by the extension support portion 93, and the tooth width of the pinion gear 49 can be used to transmit the driving force. The deformation of the holes 51 is reduced. or,
The effect of preventing the pinion gear 49 from falling down and the effect of preventing uneven wear and seizure are also improved accordingly.

In addition to the gear portion 79, the slide support portion 77 supported by the support hole 51 is provided in the pinion gear 49, so that the surface pressure between the gear portion 79 and the support hole 51 and the slide support portion 77. The surface pressure between the support hole 51 and the support hole 51 is reduced, and the effect of preventing uneven wear and seizure between the pinion gear 49 and the support hole 51 and the effect of preventing the pinion gear 49 from falling are improved accordingly.

Further, a gear is also processed on the sliding support portion 77 so as to be integrated with the gear portion 79, so that the differential case 37
The oil flowing from the opening 111 of the pinion gear 49 is forcibly guided to each meshing portion of the gear portion 79, the sun gear 55, and the internal gear 53 as the pinion gear 49 rotates, and effectively lubricates them. The effect of preventing seizure between the gear and the support hole 51 and the effect of lubricating the meshing portion of each gear are improved.

The centrifugal force of the pinion gear 49 while the center differential 7 is rotating is received by the outer peripheral portion 95 of the support hole 51. As described above, since the width 97 of the outer peripheral portion 95 is wider than the half tooth width 99 of the pinion gear 49, the pinion gear 49 is reliably held, and the pinion gear 49 is prevented from falling due to centrifugal force.

Further, since the differential case 37 is composed of one member having the driving force input portion (bolt hole 45) and the support hole 51 of the pinion gear 49, the number of parts is small and the cost is accordingly low. Unlike the differential case in which the respective gears are supported by different members, the differential case is not affected by the processing accuracy of each component or an error during assembly. Therefore, the supporting condition of each gear, especially the pinion gear 49, is improved, uneven wear and seizure are prevented, durability is improved, and the normal function of the center differential 7 is maintained for a long time.

In addition to this, the sun gear 55 is hollow,
By penetrating the output shaft (axle 15) of the front differential 13, it is possible to arrange the center differential 7 and the front differential 13 coaxially as shown in FIG. 11. By arranging these coaxially, the transfer 5 is compact. Became.

As described above, the center differential 7 obtains a large torque distribution ratio, prevents the pinion gear 49 from falling down, has improved durability, and maintains normal operation for a long time.

The vehicle equipped with the center differential 7 has its torque sensitive differential limiting function to stabilize the behavior of the vehicle body when a large torque is applied, such as at the time of starting or accelerating, and at the same time, the center differential as described above is used. Due to the durability improving effect of the diff 7, excellent maneuverability and runnability can be obtained for a long period of time.

Further, since the center differential 7 sends a large driving torque to the rear wheels 33, 35 to which the load moves during acceleration, the acceleration of the vehicle is improved.

Next, the second embodiment of the present invention will be described with reference to FIGS.
An embodiment will be described. This embodiment corresponds to claims 1, 2,
It has the characteristics of 3, 4, 6, 7, 8, and 9. FIG. 4 shows the differential device of this embodiment. The left and right directions are the left and right directions in the vehicle of FIG. 11 and FIG. 4, and members and the like not given reference numerals are not shown.

In FIG. 4 and FIG. 11 and the description of the second embodiment, the same functional members as those of the center differential 7 of the first embodiment are designated by the same reference numerals, and the duplicate description except for the main part is given. Is omitted.

The differential device of FIG. 4 is used as the center differential 117 of FIG. 11, and distributes the driving force of the engine 1 to the front wheels 19 and 21 and the rear wheels 33 and 35.

As shown in FIG. 4, the center differential 117 is composed of a differential case 119, a pinion gear 49, an internal gear 53, a sun gear 55 and the like. The differential case 119 and the internal gear 53 are respectively provided with bearings 48 in the transfer case 11. It is supported internally.

The differential case 119 has a left end portion (one side in the axial direction).
Is connected to an input gear 123 (shown by a broken line in FIG. 11) by a spline portion 121 (driving force input section) provided on the output gear 125 of the transmission 3 (shown by a broken line in FIG. 11). Is meshing with.
In this way, the differential case 119 is rotationally driven by the driving force of the engine 1.

The sun gear 55 is supported on the inner circumference of the differential case 119 by the left hub portion 67, and is supported on the inner circumference of the hub portion 59 of the internal gear 53 by the right hub portion 69 (output shaft on the front wheel side). A spiral oil groove 127 is provided on the inner circumference of the differential case 119 to supply oil to a sliding portion with the left hub portion 67.

Thrust washers 73 and 75 are disposed between the sun gear 55 and the differential case 119 and the flange portion 57 of the internal gear 53, respectively.

As shown in FIG. 11, the internal gear 5
3 is connected to the rear wheel side from the gear transmission mechanism 107 via the direction changing mechanism 9, and the sun gear 55 is spline-connected to the differential case 109 side of the front differential 13. The left axle 15 of the front differential 13 is the hub portion 6 of the sun gear 55.
It penetrates through 7,69.

As shown in FIG. 4, each pinion gear 49 is slidably rotatably supported in the support hole 129 of the differential case 119, and the gear portion 79 meshes with the sun gear 55 on the radially inner side and the internal on the radially outer side. It meshes with the gear 53. The left and right end surfaces of each pinion gear 49 face the differential case 119 and the flange portion 57 of the internal gear 53, respectively.

The right end portion 81 of the sun gear 55, the meshing portion 83 between each pinion gear 49, and the meshing portion 85 between each pinion gear 49 and the internal gear 53 are indicated by arrows 8 in FIG.
In the range of 7, they overlap in the radial direction.

As shown in FIG. 4, the support hole 129 of the differential case 119 is provided with the entire circumference support portion 131 and the extension support portion 133, and the entire circumference support portion 131 covers the sliding support portion 77 of each pinion gear 49 over the entire circumference. The extension support portion 133 supports an overlap portion 91 in which each pinion gear 49 overlaps with and meshes with the sun gear 55 and the internal gear 53.

Further, the width 13 of the outer peripheral portion 135 of the support hole 129
7 is wider than the half tooth width 99 of each pinion gear 49. The left end portion 101 of the sun gear 55 is the outer peripheral portion 135.
And are facing in the radial direction.

Engine 1 for rotating differential case 119
Driving force is distributed from each pinion gear 49 via gears 53, 55, a large driving torque is sent to the rear wheels 33, 35, and a smaller driving torque is sent to the front wheels 19, 21. Thus, the unequal torque distribution characteristic for the center differential is obtained.

If a driving resistance difference occurs between the front wheels and the rear wheels during traveling on a rough road, the driving force of the engine 1 is differentially distributed to the front and rear sides by the rotation of each pinion gear 49.

During the transmission of torque, frictional resistance is generated at the meshing portion of each gear, and each pinion gear 49 is pressed against the support hole 129 of the differential case 119 by the meshing reaction force with the sun gear 55 to generate frictional resistance.

Further, due to the meshing thrust force of the helical gear, both end faces of each pinion gear 49 and the differential case 11 are
9 and the flange portion 57 of the internal gear 53, frictional resistance is generated between the end faces of the sun gear 55 and the differential case 119 and the flange portion 57 via the thrust washers 73 and 75.

Due to these frictional resistances, a torque sensitive differential limiting function can be obtained.

As shown in FIG. 4, a gap 139 is provided between the differential case 119 and the internal gear 53. The oil splashed from the oil sump of the transfer case 11 flows into the inside of the differential case 119 and the internal gear 53 through the gap 139 and the oil groove 127 on the inner periphery of the differential case 119, and the meshing portions of the gears and the torque sensitive type difference. It is supplied to each sliding part that generates a motion limiting force and sufficiently lubricates them.

In this way, the center differential 117 is constructed.

As described above, the center differential 117 obtains a large torque distribution ratio by using the internal gear 53 and the sun gear 55.

In addition to this, the meshing portion 83 of the pinion gear 49 with respect to the sun gear 55 and the internal gear 53.
Since the meshing portion 85 with respect to each other is overlapped in the direction of the meshing reaction force and these meshing reaction forces are canceled to reduce the tilting torque of each pinion gear 49, the pinion gear 49 and the support hole 129 due to the tilting of each pinion gear 49 The uneven wear and seizure of the gears are prevented, the tooth contact of each gear is kept good, and the strength and durability of each gear are improved.

Further, since the outer peripheral portion 135 of the support hole 129 receives the meshing reaction force input from the left end portion 101 of the sun gear 55 to the pinion gear 49 and disperses the force applied to the pinion gear 49, it is advantageous in terms of strength and durability of the pinion gear 49. Sexuality is improved accordingly.

Further, since the supporting hole 129 is provided with the entire circumference supporting portion 131 for supporting the entire circumference of the pinion gear 49, the supporting state of the pinion gear 49 is further improved, and the pinion gear 4
9 and the support hole 129, the effect of preventing uneven wear and seizure and the effect of improving the tooth contact of each gear are improved.

Further, since the support hole 129 is provided with the extension support portion 133 for supporting the overlap portion 91 of the pinion gear 49, the support width of the pinion gear 49 by the support hole 129 becomes wider in the tooth width direction, and the pinion gear 4
Since the rotational driving force of the differential case 119 can be transmitted by widely using the tooth width of 9, the deformation of the support hole 129 is reduced. Further, the effect of preventing the pinion gear 49 from falling down and the effect of preventing uneven wear and seizure are further improved.

Further, the slide support portion 77 is attached to each pinion gear 49.
By providing the pinion gear 49, the surface pressure is reduced over the entire tooth width of the pinion gear 49, and the pinion gear 49 and the support hole 129 are provided.
Effect of preventing uneven wear and seizure with pinion gear 49
The fall-prevention effect is further improved.

Further, the sliding support portion 77 is also machined with a gear so as to be integrated with the gear portion 79, so that the oil flowing in from the outside meshes with each sliding portion and each gear as the pinion gear 49 rotates. Since it is forcibly guided to a portion or the like, the effect of preventing seizure between the pinion gear 49 and the support hole 129 and the effect of lubricating the meshed portion of each gear are improved.

Further, the centrifugal force of the pinion gear 49 while the center differential 117 is rotating is the outer peripheral portion 1 of the support hole 129.
35 receives. As described above, the width 1 of this outer peripheral portion 135
Since 37 is wider than the half tooth width 99 of the pinion gear 49, the pinion gear 49 is reliably held, and the pinion gear 49 is prevented from falling due to centrifugal force.

The differential case 119 is provided with a driving force input portion (spline portion 121) and a support hole 1 for the pinion gear 49.
Since the casing member 39 is not used unlike the center diff 7 unlike the center differential 7, the number of parts is small and the cost is low, and each gear is supported by different members. Unlike the differential case with a divided structure, it is not affected by the processing accuracy of each component or the error during assembly. Therefore, the supporting condition of each gear, particularly the pinion gear 49, is improved, uneven wear and seizure are prevented, durability is improved, and the normal function of the center differential 117 is maintained for a long time.

Further, the differential case 1 of the center differential 117
Unlike the bolt hole 45 of the diff case 37 of the center differential 7, the driving force input portion (spline portion 121) is arranged not at the radial outer side but at the axial end portion, so that the diameter is small and compact. And is advantageous in layout.

Further, since the internal gear 53 is exposed to the outside, it is easy to lubricate and cool the inside of the center differential 117, and the durability is improved accordingly.

Further, by making the sun gear 55 hollow and penetrating the output shaft (axle 15) of the front differential 13,
As shown in FIG. 11, the center differential 117 and the front differential 1
The transfer 5 can be made compact because the coaxial arrangement with the 3 is possible.

As described above, the center differential 117 obtains a large torque distribution ratio, prevents the pinion gear 49 from collapsing, improves durability, and maintains normal operation for a long time.

In the vehicle equipped with the center differential 117, the torque sensitive differential limiting function stabilizes the behavior of the vehicle body when a large torque is applied, such as at the time of starting or accelerating, and at the same time as the above center. Due to the durability improving effect of the diff 117, excellent maneuverability and runnability can be obtained over a long period of time. Further, since the center differential 117 sends a large driving torque to the rear wheels 33, 35 to which the load moves during acceleration, the acceleration of the vehicle is improved.

Next, a third embodiment of the present invention will be described with reference to FIGS. 5 to 9 and 11. This embodiment comprises the features of claims 1, 3, 4, 5, 6, 7, 8, 9.
FIG. 5 shows the differential device of this embodiment. The left and right directions are the left and right directions in the vehicle of FIG. 11 and FIG. 5, and members and the like not given reference numerals are not shown.

In the drawings and the description of the third embodiment, the center differentials 7 and 11 of the first and second embodiments are described.
The members having the same functions as the members of 7 are given the same reference numerals, and the duplicated description except for the main part will be omitted.

The differential device of FIG. 5 is used as the center differential 141 of FIG. 11, and distributes the driving force of the engine 1 to the front wheels 19 and 21 and the rear wheels 33 and 35.

As shown in FIG. 5, the center differential 141 is composed of a differential case 143, a pinion gear 49, an internal gear 53, a sun gear 55 and the like.

The differential case 143 is the casing body 145.
And a plate 147 (plate member), and the plate 147 is axially positioned by a bearing 48. The casing body 145 of the differential case 143 and the internal gear 53 are supported inside the transfer case 11 by bearings 48, respectively.

The differential case 143 is the casing body 145.
14 provided on the left end (one side in the axial direction) of the
9 (driving force input section) is connected to the input gear 123, and this input gear 123 meshes with the output gear 125 of the transmission 3. In this way, differential case 1
43 is rotationally driven by the driving force of the engine 1.

The sun gear 55 is supported on the inner circumference of the casing body 145 by the left hub portion 67, and is supported on the inner circumference of the hub portion 59 of the internal gear 53 by the right hub portion 69.

Thrust washers 73 and 75 are arranged between the sun gear 55 and the casing body 145 and the flange portion 57 of the internal gear 53, respectively.

As shown in FIGS. 5, 6, and 7, the differential case 143.
A supporting wall 151 is formed on the casing main body 145 of the casing main body 145. The supporting wall 151 is arranged between each pinion gear 49 and the flange portion 57 of the internal gear 53, and supports the right end surface of each pinion gear 49. . Further, as shown in FIGS. 5 and 6, the plate member 147 includes a support wall 153 that supports the left end surface of each pinion gear.

The gear portion 79 of each pinion gear 49 meshes with the sun gear 55 on the inner side in the radial direction and meshes with the internal gear 53 on the outer side in the radial direction.
5 overlaps in the radial direction within the range of arrow 87 in FIG.

Casing body 145 of differential case 143
Has a support hole 155 for slidably and rotatably supporting each pinion gear 49. As shown in FIGS.
Reference numeral 5 includes an entire circumference support portion 157 and an extension support portion 159. The entire circumference support portion 157 supports the sliding support portion 77 of each pinion gear 49 over the entire circumference, and the extension support portion 159 is shown in FIG.
As in 6, 7, and 9, each pinion gear 49 is a sun gear 5.
5 and the internal gear 53 are supported by an overlapping portion 91 which is meshed with each other.

Further, the width 16 of the outer peripheral portion 161 of the support hole 155 is
3 is wider than the half tooth width 99 of each pinion gear 49. The left end portion 101 of the sun gear 55 is the outer peripheral portion 161.
And are facing in the radial direction.

Engine 1 for rotating differential case 143
Driving force is distributed from each pinion gear 49 via gears 53, 55, a large driving torque is sent to the rear wheels 33, 35, and a smaller driving torque is sent to the front wheels 19, 21. Thus, the unequal torque distribution characteristic for the center differential is obtained.

Further, for example, when a driving resistance difference occurs between the front wheels and the rear wheels during traveling on a rough road, the driving force of the engine 1 is differentially distributed to the front and rear sides by the rotation of each pinion gear 49.

During the transmission of the torque, frictional resistance is generated at the meshing portion of each gear, and the outer periphery of each pinion gear 49 is pressed against the support hole 155 of the casing body 145 by the reaction force of meshing with the sun gear 55, so that the frictional resistance is generated. Occur.

Further, due to the meshing thrust force of the helical gear, both end faces of each pinion gear 49, the supporting wall 151 of the casing body 145 and the supporting wall 1 of the plate member 147 are supported.
Frictional resistance is generated between 53 and the thrust washer 7.
Friction resistance is generated between the both end surfaces of the sun gear 55 and the casing main body 145 and the flange portion 57 of the internal gear 53 via the holes 3 and 75.

Due to these frictional resistances, a torque sensitive differential limiting function can be obtained.

As shown in FIG. 5, a gap 165 is provided between the casing body 145 and the plate member 147, and a gap 167 is provided between the casing body 145 and the internal gear 53. Transfer case 11
The oil splashed from the oil reservoir of the above flows into the inside of the differential case 143 and the internal gear 53 through these gaps 165 and 167, and meshes with each gear and each sliding motion that generates a torque sensitive differential limiting force. Are supplied to the parts and lubricate them sufficiently.

In this way, the center differential 141 is constructed.

As described above, the center differential 141 obtains a large torque distribution ratio by using the internal gear 53 and the sun gear 55.

In addition to this, each meshing portion 8 of the pinion gear 49 with respect to the sun gear 55 and the internal gear 53
Since 3,85 are overlapped in the radial direction to cancel out the meshing reaction force and reduce the tilting torque of each pinion gear 49, the pinion gear 49 and the supporting hole 155 are unevenly worn or seized due to the tilting of each pinion gear 49. Is prevented and the tooth contact of each gear is kept good,
The strength and durability of each gear are improved.

Further, the meshing reaction force input from the left end portion 101 of the sun gear 55 to the pinion gear 49 is received by the outer peripheral portion 161 of the support hole 155. Therefore, the force applied to the pinion gear 49 is dispersed, which is advantageous in terms of strength and the pinion gear 49. The durability is improved accordingly.

Further, since the supporting hole 155 is provided with the entire circumference supporting portion 157 for supporting the entire circumference of the pinion gear 49,
The support state of the pinion gear 49 is further improved, and the effect of preventing uneven wear and seizure of the pinion gear 49 and the support hole 155 and the effect of improving the tooth contact of each gear are improved.

Further, since the support hole 155 is provided with the extension support portion 159 for supporting the overlap portion 91 of the pinion gear 49, the support width of the pinion gear 49 by the support hole 155 is widened in the tooth width direction, and the pinion gear 4 is supported.
Since the rotational driving force of the differential case 143 can be transmitted by using the tooth width of 9 widely, the deformation of the support hole 155 is reduced. Further, the effect of preventing the pinion gear 49 from falling down and the effect of preventing uneven wear and seizure are further improved.

Also, the slide support portion 77 is attached to each pinion gear 49.
By providing the pinion gear 49, the surface pressure is reduced over the entire tooth width of the pinion gear 49, and the pinion gear 49 and the support hole 155 are provided.
Effect of preventing uneven wear and seizure with pinion gear 49
The fall-prevention effect is further improved.

Further, the sliding support portion 77 is also processed with a gear so as to be integrated with the gear portion 79, so that the oil flowing in from the outside meshes with each sliding portion and each gear as the pinion gear 49 rotates. Since it is forcibly guided to a portion or the like, the effect of preventing seizure between the pinion gear 49 and the support hole 155 and the effect of lubricating the meshing portion of each gear are improved.

Further, the centrifugal force of the pinion gear 49 when the center differential 141 is rotating is the outer peripheral portion 1 of the support hole 155.
61 receives. As described above, the width 1 of this outer peripheral portion 161
Since 63 is wider than the half tooth width 99 of the pinion gear 49, the pinion gear 49 is reliably held and the pinion gear 49 is prevented from falling due to centrifugal force.

In the differential case 143, the casing body 145 is provided with the support wall 151 and the plate member 147 is provided with the support wall 153 to support both end surfaces of the pinion gear 49. Therefore, the support holes 155 are formed in the respective pinion gears 49. Can be formed over the entire tooth width of
Since sufficient strength is obtained, the surface pressure of the support holes 155 is reduced accordingly, deformation is prevented, the pinion gears 49 are reliably supported, and uneven wear and seizure are prevented, and the pinion gears 49 are prevented from falling. The tooth contact of each gear is improved. The plate member 147 may be fixed to the differential case 143 with bolts.

Since the support hole 155 of each pinion gear 49 is formed only in the casing main body 145, unlike the differential case in which each gear is supported by a different member, the pinion gear 49 is well supported and uneven wear or seizure occurs. Is prevented, the durability is improved, and the normal function of the center differential 141 is maintained for a long time.

Further, the differential case 1 of the center differential 141
43, the driving force input portion (spline portion 149) is arranged at the end portion in the axial direction, not at the outside in the radial direction, so that the diameter is small and compact, which is advantageous in layout.

Further, since the internal gear 53 is exposed to the outside, it is easy to lubricate and cool the inside of the center differential 141, and the durability is improved accordingly.

Further, by making the sun gear 55 hollow and penetrating the output shaft (axle 15) of the front differential 13,
As shown in FIG. 11, the center differential 141 and the front differential 13 can be coaxially arranged, and the transfer 5 is made compact.

As described above, the center differential 141 obtains a large torque distribution ratio, prevents the pinion gear 49 from collapsing, improves durability, and maintains normal operation for a long time.

In the vehicle equipped with the center differential 141, the torque sensitive differential limiting function stabilizes the behavior of the vehicle body when a large torque is applied such as at the time of starting or accelerating, and the center differential 141 as described above is used. Due to the effect of improving the durability of the differential 141, excellent maneuverability and runnability can be obtained over a long period of time. Further, since the center differential 141 sends a large driving torque to the rear wheels 33, 35 to which the load moves during acceleration, the acceleration of the vehicle is improved.

Next, referring to FIGS. 10 and 11, the fourth embodiment of the present invention will be described.
An embodiment will be described. This embodiment corresponds to claims 1, 3,
It has 4, 5, 6, 7, 8, and 9 features. FIG. 10 shows the differential device of this embodiment. The left and right directions are the left and right directions in the vehicle of FIG. 11 and FIG. 10, and members and the like not given reference numerals are not shown.

In the differential device of the present invention,
The sliding support portion of the pinion gear does not have to have a gear. The differential device of the fourth embodiment is an example in which a pinion gear that is not gear-processed is used for the sliding support portion in the center differential 141 of the third embodiment, and therefore only the differences from the center differential 141 will be described. .

The differential device of FIG. 10 is used as the center differential 169 of FIG. 11, and distributes the driving force of the engine 1 to the front wheels 19 and 21 and the rear wheels 33 and 35.

As shown in FIG. 10, the center differential 169 is
The differential case 143, the pinion gear 171, the internal gear 53, the sun gear 55 and the like are included.

Each pinion gear 171 is composed of a cylindrical sliding support portion 173, a gear portion 175, and a circumferential groove 177 provided between them.
It is slidably and rotatably supported by 55.

The sliding support portion 173 is supported by the entire circumference support portion 157 of the support hole 155. Further, the gear portion 175 meshes with the sun gear 55 on the radially inner side and meshes with the internal gear 53 on the radially outer side. These meshing portions 179, 181 are radially over in the range of arrow 87 in FIG. I'm wrapping.

Overlap portion 183 in which each pinion gear 49 meshes with the sun gear 55 and the internal gear 53.
Is supported by the extension support portion 159 of the casing body 145. The width 163 of the outer peripheral portion 161 of the support hole 155 is wider than the half width 185 of each pinion gear 171.

Engine 1 for rotating differential case 143
Driving force is distributed from each pinion gear 171 via gears 53, 55, a large driving torque is sent to the rear wheels 33, 35, and a smaller driving torque is sent to the front wheels 19, 21. Further, for example, when a driving resistance difference occurs between the front wheels and the rear wheels during traveling on a rough road, the driving force of the engine 1 is differentially distributed to the front and rear sides by the rotation of each pinion gear 171.

During the transmission of torque, frictional resistance is generated at the meshing portion of each gear, frictional resistance is generated between each pinion gear 171 and the support hole 155 due to the meshing reaction force, and further due to the meshing thrust force of the helical gear, The sun gear 5 is interposed between each pinion gear 171, the support wall 151 and the support wall 153 and via the thrust washers 73 and 75.
Friction resistance is generated between both end surfaces of the casing 5, the casing body 145, and the flange portion 57 of the internal gear 53.

Due to these frictional resistances, a torque sensitive differential limiting function can be obtained.

In this way, the center differential 169 is constructed.

As described above, the center differential 169 obtains a large torque distribution ratio.

In addition to this, since the meshing portions 179 and 181 of the pinion gear 171 are radially overlapped to cancel the meshing reaction force and prevent the pinion gears 171 from falling down, the pinion gear 171 and the support hole 155 are prevented from collapsing. Uneven wear and seizure are prevented, the tooth contact of each gear is kept good, and the strength and durability of each gear are improved.

The meshing reaction force input from the left end portion 101 of the sun gear 55 to the pinion gear 171 is the support hole 155.
Since the outer peripheral portion 161 of the pinion gear 171 is received, the force applied to the pinion gear 171 is dispersed, which is advantageous in terms of strength.
The durability of 71 is improved accordingly.

Further, by providing the supporting hole 155 with the entire circumference supporting portion 157 for supporting the entire circumference of the pinion gear 171, the supporting state of the pinion gear 171 is further improved, and uneven wear and seizure of the pinion gear 171 and the supporting hole 155 are prevented. The prevention effect and the tooth contact improvement effect of each gear are improved.

Further, since the support hole 155 is provided with the extension support portion 159 for supporting the overlap portion 183 of the pinion gear 171, the pinion gear 1 formed by the support hole 155 is provided.
The support width of 71 becomes wider in the tooth width direction, and the tooth drive of the differential case 143 can be transmitted by using the tooth width of the pinion gear 171 widely, so that the deformation of the support hole 155 is reduced. Further, the effect of preventing the pinion gear 171 from falling and the effect of preventing uneven wear and seizure are further improved.

Further, the sliding support portion 1 is attached to each pinion gear 171.
By providing 73, the surface pressure is reduced over the entire width of the pinion gear 171, and the pinion gear 171 and the support hole 1
The effect of preventing uneven wear and seizure with 55 and the effect of preventing the pinion gear 171 from falling are further improved.

Since no gear is machined in the sliding support portion 173, the machining is easy, and since the sliding support portion 173 has a cylindrical shape, the sliding area with the support hole 155 is larger than that of the gear. Increases and the surface pressure decreases, and the sliding support portion 173
The wear and deformation of both the support holes 155 and the support holes 155 are prevented, and the support of each pinion gear 171 is ensured.

The centrifugal force of the pinion gear 171 when the center differential 169 is rotating is received by the outer peripheral portion 161 of the support hole 155. As described above, since the width 163 of the outer peripheral portion 161 is wider than the half width 185 of the pinion gear 171, the pinion gear 171 is reliably held, and the pinion gear 171 is prevented from falling due to centrifugal force.

The differential case 143 is composed of the support wall 151 of the casing body 145 and the support wall 1 of the plate member 147.
It is configured to support both end surfaces of the pinion gear 171 by means of 53, and the support holes 155 can be formed over the entire width of each pinion gear 171, and sufficient strength can be obtained, so that the surface pressure of the support holes 155 is reduced accordingly. , Deformation is prevented, and the support of each pinion gear 171 is ensured,
The effect of preventing uneven wear and seizure, and the pinion gear 171
The fall prevention effect and tooth contact of each gear are improved.

Since the support hole 155 of each pinion gear 171 is formed only in the casing body 145, unlike the differential case in which each gear is supported by a different member, the pinion gear 171 is in a good supporting state, and uneven wear and seizure are caused. The center differential 169
The normal function of is maintained for a long time.

In the differential gear of the present invention, each gear may be a spur gear.

[0158]

According to the differential device of the present invention, a large torque distribution ratio is obtained by using a sun gear and an internal gear as output gears, and a torque sensitive differential limiting function is obtained. The meshing part of the pinion gear with respect to the sun gear and the internal gear is overlapped in the radial direction to cancel the meshing reaction force and reduce the tilting torque of each pinion gear.

Therefore, uneven wear and seizure of the pinion gear and the pinion gear support hole due to the tilting of the pinion gear are prevented, and the tooth contact of each gear is maintained well, and the strength and durability of each gear are improved.

The differential device according to claims 2 to 9 is similar to the differential device according to claim 1,
A large torque distribution ratio and a torque-sensitive differential limiting function are obtained, and uneven wear and seizure of the pinion gear and support holes due to tilting of the pinion gear are prevented, good tooth contact of each gear is maintained and strength and durability. And improve.

In addition to this, in the differential device according to the second aspect, the differential case is composed of one member,
It has a small number of parts and is low cost, and unlike a differential case with a split configuration in which each gear is supported by different members,
It is not affected by the processing accuracy and assembly error of each component, the support condition of each gear, especially the pinion gear, is improved, uneven wear and seizure are prevented, the durability is improved, and the normal function of the differential device. Is kept for a long time.

In the differential device according to the third aspect of the present invention, since the supporting hole of the differential case is provided with the entire circumference supporting portion for supporting the entire circumference of the pinion gear, the supporting state of the pinion gear is further improved, and uneven wear of the pinion gear and the supporting hole is prevented. The effect of preventing seizure and the effect of improving the tooth contact of each gear are further improved.

According to the differential device of the fourth aspect, the extension support portion of the support hole supports the pinion gear at the overlap portion, so that the support width of the pinion gear by the support hole is widened accordingly, and the pinion gear is widely used for driving. Since the force can be transmitted, the deformation of the support hole at the time of torque transmission is reduced, and the effect of preventing the pinion gear from falling down and the effect of preventing uneven wear and seizure are further improved.

According to the differential device of the fifth aspect, the support hole supports the entire tooth width of the pinion gear, and the support hole is formed in the casing body to obtain sufficient strength, so that a stable support state of the pinion gear can be obtained. Since the support holes are not deformed during the transmission of torque, the effect of preventing the pinion gear from falling and the effect of preventing uneven wear and seizure are further improved.

In the differential device of the sixth aspect, the sliding support portion supported by the support hole is provided in the pinion gear, so that the surface pressures of the gear portion, the sliding support portion, and the support hole are respectively reduced to support the pinion gear. The effect of preventing uneven wear and seizure with the holes is further improved, and the effect of preventing the pinion gear from falling is further improved.

In the differential device according to the seventh aspect, the torque sensitive differential limiting function is enhanced by the frictional resistance generated by the meshing thrust force of the helical gear.

In the differential device according to the eighth aspect, the output shaft of the inter-axle differential is passed through the hollow sun gear, which enables coaxial disposition with the inter-axle differential. The traction system of the driving car becomes compact.

According to a ninth aspect of the present invention, in a differential device, a drive force input portion of a differential case and output shafts of a sun gear and an internal gear are arranged on one side and the other side in the axial direction, respectively, to form a power system for a four-wheel drive vehicle. Has been established.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

3 is a vertical cross-sectional view of a single diff case used in the embodiment of FIG.

FIG. 4 is a sectional view showing a second embodiment of the present invention.

FIG. 5 is a sectional view showing a third embodiment of the present invention.

6 is a vertical cross-sectional view of the differential case used in the embodiment of FIG.

FIG. 7 is a sectional view taken along line BB of FIG. 5;

FIG. 8 is a sectional view taken along line CC of FIG. 6;

9 is a cross-sectional view taken along line DD of FIG.

FIG. 10 is a cross-sectional view showing a fourth embodiment of the present invention.

FIG. 11 is a skeleton mechanism diagram showing a power system of a four-wheel drive vehicle using the differential device of each embodiment.

FIG. 12 is a sectional view of a conventional example.

FIG. 13 is a cross-sectional view of another conventional example.

[Explanation of symbols]

7, 117, 141, 169 Center differential (differential device) 13 Front differential (wheel-to-wheel differential) 15 Front axle (wheel-side differential one-sided output shaft) 37, 119, 143 Differential case 45 Bolt hole (driving force input part) ) 49,171 Pinion gears 51, 129,155 Support holes 53 Output side internal gears 55 Output side sun gears 57 Flange parts of internal gears 59 Hub parts (output shafts of internal gears) 69 Hub parts (output shafts of sun gears) 77 173 Sliding support portion 79, 175 Gear portion 83, 179 Pinion gear and sun gear meshing portion 85, 18 1 Pinion gear and internal gear meshing portion 89, 131, 157 Full circumference support portion 93, 133, 159 Extension support portion 121, 149 Spline part (driving force input part) 145 KASHIN Body 147 plates (plate member) 151 housing the pinion gear support wall 153 plate pinion gear supporting wall of the body

Claims (9)

[Claims] 1. A differential case which is rotationally driven by a driving force of an engine, a support hole formed in the differential case, a plurality of pinion gears whose outer periphery is slidably supported by the support holes, and an inner side of each pinion gear. Is equipped with an output-side sun gear that meshes with these pinion gears and an output-side internal gear that meshes with these pinion gears on the outside of each pinion gear. A differential device characterized in that the part overlaps in the radial direction. 2. The differential case is composed of one member having a drive force input portion and a pinion gear support hole.
Differential device. 3. The differential device according to claim 1, wherein the support hole has a full-circumference support portion that supports the full circumference of the pinion gear. 4. The differential device according to claim 1, wherein the support hole has an extension support portion that supports the pinion gear at a portion where a meshing portion with the sun gear and a meshing portion with the internal gear overlap each other. 5. The differential case comprises a casing body having a support wall for the pinion gear between one end surface of the pinion gear and the flange portion of the internal gear, and a plate member having a support wall for the other end surface of the pinion gear. The differential device according to any one of items 1 to 4. 6. The differential device according to claim 1, wherein the pinion gear includes a gear portion that meshes with the sun gear and the internal gear, and a slide support portion supported by the support hole. 7. The differential device according to claim 1, wherein each gear is a helical gear. 8. The differential device according to claim 1, wherein the sun gear is formed hollow, and the one-side output shaft of the front or rear wheel inter-axle differential is passed through the sun gear. 9. The differential device according to claim 1, wherein the drive force input section of the differential case is arranged on one side in the axial direction, and the output shafts of the sun gear and the internal gear are arranged on the other side in the axial direction.