JP2003269576A - Differential device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To simplify the shape of a differential case, to discontinue surface hardening, and to attain a low cost. <P>SOLUTION: This differential device is provided with a differential case 3 rotated by driving force of an engine, a pair of pinion gears meshing with side gears 15, 17 mutually by a second gear part and individually meshing with the side gears 15, 17 by a first gear part, and a storage hole for the pinion gears. A support part 61 supporting the periphery of the pinion gear is formed at a boss part 19 of the side gear 15. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication (Kokai) No. 3-37455 discloses a differential device 501 as shown in FIG.

This differential device 501 includes a differential case 503, a plurality of sets of helical pinion gears 505 ,.
507, output side helical side gears 509 and 511, and housing holes 513 and 515 formed in the differential case 503.

The pinion gears 505 and 507 mesh with each other, one side gear 509 meshes with the pinion gear 505, and the other side gear 511 meshes with the pinion gear 507. In addition, each accommodation hole 51
3, 515 respectively accommodate the pinion gears 505, 507 so as to be slidably rotatable.

The differential case 503 is rotated by the driving force of the engine, and the rotation thereof is the helical pinion gear 505.
It is distributed to the wheel side from 507 via the helical side gears 509 and 511.

While transmitting the torque, the pinion gear 5
05 and 507 are pressed against the wall surfaces of the housing holes 513 and 515 by a reaction force and a centrifugal force that mesh with the side gears 509 and 511 to generate frictional resistance, and the meshing thrust force of the helical gears causes the pinion gears 505 and 505 to move.
The end faces of 07 and the side gears 509 and 511 are pressed by the differential case 503 to generate frictional resistance, and a torque sensitive differential limiting function is obtained by these frictional resistances.

The differential case 503 is a case member 51.
The left case member 517 has a petal having a plurality of pinion gear 505 housing holes 513 arranged at equal intervals on the circumference of the housing hole 523 of the side gear 509. A shaped recess is formed.

[0008]

In the differential device having the structure such as the differential device 501, the accommodation hole 523 (support portion) for supporting the side gear 509 is provided.
Then, it is necessary to provide the case member 517 with a complicated (petal-shaped) recess having the shape of the accommodation hole 513 of the pinion gear 505, which is difficult to process and requires a large processing cost.

Further, in order to impart sufficient abrasion resistance to the respective accommodation holes 513, 523, the case member 517 is carburized and then quenched, or the case member 517 is subjected to quenching.
It is necessary to carry out a surface hardening treatment such as a nitriding treatment, which increases the cost.

Further, when the surface is hardened, not only the petal-shaped recesses but also the machining surfaces of the case members 517 and 519 (or the flange surfaces of the case members if the mating surfaces are flanges) can be machined. Becomes extremely difficult,
The processing cost will increase further.

Therefore, the present invention is a differential device configured to connect an output side gear via a pinion gear supported in a housing hole, which simplifies the shape and processing of the differential case, and also the differential case. It is an object of the present invention to provide a differential device in which the cost is significantly reduced by eliminating or simplifying the surface hardening treatment of.

[0012]

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 a prime mover, a pair of output side gears which are rotatably supported inside the differential case, and a second gear. A pair of pinion gears that connect the two side gears by meshing with each other by the first gear portion and the side gears separately by the first gear portion, and a storage hole that slidably and rotatably stores the respective pinion gears. At least one of the boss portions on at least one side in the axial direction is provided with a support portion that supports the outer periphery of the pinion gear.

As described above, in the differential device of the present invention, the side gear and the pinion gear are configured to support each other by supporting the pinion gear by the support portion provided on the boss portion of the side gear. The side case member (for example, the cover) does not need to be provided with a side gear support portion or a pinion gear accommodation hole, and therefore, a surface hardening treatment for imparting abrasion resistance to the support portion or accommodation hole is performed on this case member. There is no need to give it.

For example, when the differential case is composed of a casing body having an opening on one side in the axial direction and a flange-like cover fixed to the opening, if the supporting portion of the side gear is provided on this cover side, the cover is provided. In addition, it is not necessary to process the petal-shaped recess formed by the support part of the side gear and the accommodation hole of the pinion gear, and the processing cost is greatly reduced.In addition, the cost increase due to the surface hardening treatment is avoided and the casing body and Machining such as the mating surface of the is facilitated and the machining cost is further reduced.

A second aspect of the present invention is the differential device according to the first aspect, wherein the second gear portion of the pinion gear meshes with one of the two side gears on the axially outer side. At the same time, the support portion on the side gear is provided so as to face the meshing portion side of the second gear portion, and the same operation and effect as the configuration of claim 1 can be obtained.

A third aspect of the present invention is the differential device according to the first aspect, wherein the second gear portion of the pinion gear is meshed with each other on both outer sides in the axial direction of the both side gears. The support part of
It is characterized in that it is provided so as to face both meshing portions of the second gear portion, respectively, and it is possible to obtain the same actions and effects as the configuration of claim 1.

According to a fourth aspect of the present invention, in the differential device according to the first aspect, the second gear portion of the pinion gear meshes with each other on the inner side in the axial direction of the both side gears, and on the side gear. The support portion is provided so as to face the meshing portion side of the second gear portion, and an operation equivalent to that of the configuration of claim 1.
The effect can be obtained.

A fifth aspect of the present invention is the differential device according to any one of the first to fourth aspects, wherein a ring member is fixed to the boss portion of the side gear, and the support portion for the pinion gear is provided. Is a cylindrical portion provided on the ring member.
It is possible to obtain the same operation and effect as the configuration of.

Further, the ring member having a cylindrical outer periphery is extremely easy to process and can be implemented at a low cost.

Further, in this structure in which the ring member is separated from the boss portion of the side gear, only the ring member is subjected to a surface hardening treatment for giving sufficient abrasion resistance to the support portion on which the pinion gear slides. Since it is good, the cost is reduced accordingly.

The invention of claim 6 is the differential device according to claim 5, characterized in that the ring member is formed integrally with the side gear, and is equivalent to the structure of claim 5. The action and effect can be obtained.

Further, in this structure, the ring member is integrated with the boss portion of the side gear, so that the number of parts and the parts cost are reduced.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] A front differential 1 (first embodiment: a differential device) will be described with reference to FIGS. In these figures, the left and right directions indicate the vehicle using the front differential 1 and the left and right directions in FIG.

The power system of this vehicle is composed of an engine (a prime mover), a transmission, a front differential 1 (a differential device for distributing the driving force of the engine to the left and right front wheels), a front axle, left and right front wheels, left and right rear wheels, and the like. Has been done.

The differential case 3 of the front differential 1 is arranged inside the transmission case, and an oil reservoir is formed in the transmission case. A ring gear is fixed to the differential case 3, and this ring gear meshes with the output gear of the transmission. The driving force of the engine is transmitted to the differential case 3 via the transmission.

As shown in FIG. 1, the differential case 3 comprises a cover 5 and a casing body 7. These cover 5 and casing body 7 are provided with respective flange portions 9, 10
Are abutted against each other, centered with each other by the engaging portion 11, and fixed with bolts 12. A pulse gear 13 for a speedometer is welded to the casing body 7.

Left and right output side helical side gears 15 and 17 are disposed inside the differential case 3, and hollow boss portions 19 and 21 formed on the respective side gears 15 and 17 support the differential case 3 (casing body 7). Parts 23 and 25
It is rotatably supported by. In addition, the side gears 15 and 17 are engaged with each other by the engaging portions 2 formed on the facing portions.
7 support each other's free ends and center them. Left and right axles (not shown) are connected to the respective side gears 15 and 17.

The left and right front axles penetrate through the left and right boss portions 29, 31 of the differential case 3, respectively, and the side gears 15, 17 are formed.
Are connected to the spline portions 33 and 35 of the. Thrust washers 37, 39 are arranged between the side gears 15, 17 and the differential case 3, respectively, and a thrust washer 41 (FIG. 3) is provided between the side gears 15, 17 (outer peripheral side of the engaging portion 27). Are arranged.

The thrust washer 37 is centered on the inner periphery at the outer periphery of the boss portion 19 of the left side gear 15, and the two claw portions 43 provided on the outer periphery are engaged with the openings 45 provided in the cover 5. It has been stopped.

The thrust washer 37 has a cover 5
An opening 47 that communicates with the other opening 45 and that facilitates the inflow and outflow of oil into and from the differential case 3 is provided.

The differential case 3 (casing body 7) is provided with four sets of long and short accommodation holes 49 and 51 at equal intervals in the circumferential direction. These accommodating holes 49 and 51 are arranged parallel to each other in the axial direction, and a long helical pinion gear 53 and a short helical pinion gear 55 are slidably accommodated therein.

The long pinion gear 53 is composed of first and second gear portions and a small-diameter shaft portion connecting these gear portions.
The gear portion meshes with the right side gear 17. Also,
The short pinion gear 55 is composed of first and second gear portions 57 and 59 having no shaft portion in the middle, the first gear portion 57 meshes with the left side gear 15, and the second gear portion 59 is the first gear portion of the pinion gear 53. 2 It meshes with the gear.

The boss portion 19 of the left side gear 15 is extended to the left side (one side of the side gears 15 and 17 in the axial direction), and a cylindrical support portion 61 is provided on the outer periphery thereof, and each pinion gear 53, 55. It supports the outer circumference of the left end of the.
Further, the left end portion of the left side gear 15 is supported by the casing body 7 by the pinion gears 53 and 55 and the housing holes 49 and 51 via the support portion 61.

The driving force of the engine 1 for rotating the differential case 3 is from the pinion gears 53, 55 to the side gear 15,
It is distributed to the left and right front wheels via 17. Further, when a driving resistance difference occurs between the front wheels due to a bad road or the like and one of the front wheels runs idle, the driving force of the engine is differentially distributed to the left and right front wheels as the pinion gears 53 and 55 rotate.

During transmission of torque, the pinion gear 5
The tooth tips of 3, 55 are pressed against the cylindrical wall surfaces of the receiving holes 49, 51 by the reaction force of meshing with the side gears 15, 17 and the centrifugal force, and sliding resistance is generated.

The left end surfaces of the pinion gears 53 and 55 are pressed against the thrust washer 37 (cover 5) by the meshing thrust force of the helical gears, and the right end surfaces of the pinion gears 53 and 55 are located in the casing body 7 (accommodating holes 49, 55).
The slide resistance is generated by being pressed against the right end surface of 51), and further, the side gears 15 and 17 and the thrust washers 37,
Sliding resistance is generated between the side gears 39 and 39 and between the side gears 15 and 17 via the thrust washer 41.

Since the pressing force of the pinion gears 53 and 55 and the meshing thrust force of the helical gear are proportional to the transmission torque of the front differential 1, the sliding resistance of these allows a torque sensitive differential limiting function to be obtained.

The direction of the meshing thrust force of the helical gear is reversed between the forward running and the backward running of the vehicle, and the location where the above sliding resistance occurs is also reversed depending on the running direction of the vehicle.

As shown in FIG. 1, the opening 45 provided in the cover 5 of the differential case 3 communicates with the receiving holes 49 and 51. When the differential case 3 (ring gear) rotates, oil is scratched from the oil reservoir of the transmission case. It is raised and flows into the accommodation holes 49, 51 from the respective openings 45, and the sliding portions of the pinion gears 53, 55, the sliding portions of the support portion 61 on the left side gear 15 (boss portion 19) and the pinion gears 53, 55. , Lubricate and cool the meshing parts of each gear.

Further, spiral oil grooves 63 and 65 are provided on the inner circumferences of the boss portions 29 and 31 of the differential case 3, and the oil grooves 63 and 65 are rotated by the rotation of the differential case 3 to flow into the differential case 3 by the screw pump action. The oil is
The sliding portion between the support portion 61 and the pinion gears 53, 55, the thrust washers 37, 39, 41, the meshing portion of each gear,
After lubricating / cooling the housing holes 49, 51 and the like, they are discharged to the outside through the opening 45 and returned to the oil sump.

Further, such oil circulation is promoted by the pumping action of the helical gear accompanying the meshing rotation of the side gears 15 and 17 and the pinion gears 53 and 55,
Lubrication / cooling effect is improved.

Thus, the front differential 1 is constructed. In the front differential 1, the left side gear 15 has the boss portion 19
By supporting the pinion gears 53, 55 by the support portion 61 provided on the side gear 15 and the pinion gears 53, 5
Since the five are configured to support each other, the support portion 61
It is not necessary to provide the support portion 23 of the left side gear 15 and the receiving holes 49 and 51 of the pinion gears 53 and 55 in the side cover 5.

Therefore, the cover 5 is subjected to a surface hardening treatment for imparting great abrasion resistance to the support portion 23 and the receiving holes 49 and 51.
Since it is not necessary to apply it on the surface, the cost increase due to the surface hardening treatment can be avoided.

Further, since the recess having a complicated shape (petal shape) formed in the cover 5 by the support portion 23 and the receiving holes 49 and 51 is eliminated, the processing cost is greatly reduced and the surface hardening treatment is performed. Since it is not present, machining of not only the petal-shaped concave portion but also the flange portion 9 that abuts the flange portion 10 of the casing body 7 and the engaging portion 11 that engages with the casing body 7 are facilitated, and the machining cost is further reduced. To be done.

Further, since the support portion 61 is integrally formed with the side gear 15 (boss portion 19), the number of parts is reduced, and the support portion 61 having a cylindrical outer periphery is extremely easy to process, and the cost is reduced accordingly. Can be implemented.

[Second Embodiment] Unlike the first embodiment, the support portion for the pinion gear provided on the boss portion of the side gear may be separate from the side gear. 4 and 5
Is a second embodiment (differential device) of the present invention and shows such an example.

The differences will be described below by quoting the members having the same functions as those of the front differential 1 of the first embodiment with the same reference numerals.

As shown in FIG. 4, a ring 101 (ring member) as shown in FIG. 5 is attached and fixed to the outer periphery of the boss portion 19 of the left side gear 15.

A cylindrical support portion 103 is formed on the outer periphery of the ring 101, and the boss portion 1 of the side gear 15 is formed.
A ring 101 (support portion 103) supports the left end portions of the pinion gears 53 and 55. Further, the left end portion of the left side gear 15 is supported by the casing body 7 via the ring 101 by the pinion gears 53 and 55 and the accommodation holes 49 and 51.

Thus, the differential device of the second embodiment is constructed, and this second embodiment has the same effect as that of the first embodiment.

In addition to this, the ring 10 having a cylindrical outer periphery is used.
Since No. 1 is extremely easy to process, it can be implemented at low cost.

Further, in this structure in which the ring 101 is separated from the boss portion 19 of the side gear 15, the pinion gear 5
Since only the ring 101 needs to be subjected to a surface hardening treatment for imparting a large amount of wear resistance to the supporting portion 103 sliding with 3, 55, the cost is further reduced.

[Third Embodiment] A front differential 301 (third embodiment: differential device) will be described with reference to FIG. In addition, the left and right directions in the figure indicate the vehicle using the front differential 401 and the left and right directions in FIG.

The front diff 301 is used in the vehicle using the front diff 1 of the first embodiment in place of the front diff 1. The members having the same functions as the front diff 1 are designated by the same reference numerals. However, the differences will be described.

Left and right output side helical side gears 303 and 305 are arranged inside the differential case 3. The side gears 303 and 305 are provided with hollow boss portions 307 and 309 that extend to the outside (both axial outsides of the side gears 303 and 305).

Side gears 303, 305 (boss portion 30
7, 309) are rotatably supported by the support portions 23, 25 of the differential case 3 (casing body 7), and the axially inner facing portions of the side gears 303, 305 are supported by ring-shaped support members 311 on the inner periphery thereof. Is supported and centered.

The left and right front axles are side gears 303 and 305.
Are connected to the spline portions 315 and 317. Thrust washers 37, 39 are arranged between the side gears 303, 305 and the differential case 3, respectively, and thrust washers 313, 313 are arranged between the side gears 303, 305 (outer peripheral side of the support member 311). ing.

In the differential case 3 (casing body 7), four sets of accommodating holes 315, 317 of equal length are formed at equal intervals in the circumferential direction. Helical pinion gears 319 and 321 are slidably and rotatably housed in these housing holes 315 and 317, respectively.

The pinion gear 319 includes the first gear portion 323, the second gear portions 325 and 327, and the first gear portion 323 and the second gear portion 325.
It consists of a small-diameter shaft portion 329 that connects with the gear portion 325,
The first gear portion 323 meshes with the right side gear 305. The other pinion gear 321 is the first gear unit 3
31, second gear portions 333, 335, and first gear portion 331
And a second gear portion 333. The first gear portion 331 meshes with the left side gear 303, and the second gear portions 333 and 335 include the pinion gear 319.
Of the second gear portions 327 and 325, respectively.

Further, cylindrical support portions 339, 3 are provided on the outer circumferences of the boss portions 307, 309 of the side gears 303, 305.
41 are provided respectively, and each pinion gear 319, 32
It supports both left and right ends of 1.

The driving force of the engine 1 for rotating the differential case 3 is from the pinion gears 319 and 321 to the side gear 3
It is distributed to the left and right front wheels via 03, 305. Also,
When one of the front wheels spins on a bad road or the like, the driving force of the engine is differentially distributed to the left and right front wheels as the pinion gears 319 and 321 rotate.

During the transmission of torque, the pinion gear 31
The tooth tips of 9, 321 are pressed against the cylindrical wall surfaces of the receiving holes 315, 317 by the reaction force of meshing with the side gears 303, 305 and the centrifugal force to generate sliding resistance.

The left end faces of the pinion gears 319 and 321 are pressed by the thrust washers 37 (cover 5) by the meshing thrust force of the helical gears, and the right end faces of the pinion gears 319 and 321 are attached to the casing body 7 (accommodating hole 3).
The sliding resistance is generated by being pressed against the right end surfaces of the gears 15, 317), and further, between the side gears 303, 305 and the thrust washers 37, 39, and the thrust washer 31.
Sliding resistance is generated between the side gears 303 and 305 via the rollers 3 and 313.

A torque sensitive differential limiting function is obtained by these sliding resistances.

In addition to the opening 45 of the cover 5, the differential case 3 has openings 343, 3 communicating with the receiving holes 315, 317.
45 is provided in the casing body 7, and the oil scraped up by the differential case 3 (ring gear) flows into the differential case 3 through the openings 45, 343, 345 and the oil grooves 63, 65 of the boss portions 29, 31. , Accommodation hole 31
5,317 and sliding parts between the pinion gears 319 and 321;
Side gears 303 and 305 (bosses 307 and 309)
Upper support portions 339 and 341 and pinion gears 319 and 32
1, sliding parts, thrust washers 37, 39, 311,
After lubricating and cooling the meshing parts of each gear, open the opening 4
It is discharged to the outside from 5, 343, 345 and returns to the oil sump.

The circulation of this oil is carried out by the side gear 30.
3,305 and the pinion gears 319, 321 are promoted by the pumping action of the helical gear accompanying the meshing rotation,
Lubrication / cooling effect is improved.

The front differential 301 is thus constructed.

The front differential 301 includes the side gear 30.
3,305 is a support portion 33 provided on the boss portions 307 and 309.
Since the side gears 303 and 305 and the pinion gears 319 and 321 are configured to support each other by supporting the pinion gears 319 and 321 with the 9, 341, the left side gear 30 is attached to the cover 5 on the support portion 339 side.
It is not necessary to form the support portion 23 of No. 3 and the accommodation holes 315 and 317 of the pinion gears 319 and 321.

Therefore, the support portion 23 and the receiving holes 315, 31
It is not necessary to subject the cover 5 to a surface hardening treatment for imparting great abrasion resistance to the cover 7, and an increase in cost due to the surface hardening treatment can be avoided.

Further, the support portion 23 and the receiving holes 315, 317
Since the petal-shaped recess formed by and is also eliminated,
Since the processing cost of the cover 5 is significantly reduced and the surface hardening treatment is not performed, not only the petal-shaped concave portion,
Processing of the flange portion 9 that abuts the flange portion 10 of the casing body 7 and machining of the engaging portion 11 that engages with the casing body 7 are facilitated, and the processing cost is further reduced.

Further, since the support portions 339 and 341 are formed integrally with the side gears 303 and 305 (boss portions 307 and 309), the number of parts is reduced, and the support portions 339 and 341 having a cylindrical outer periphery can be processed. It is extremely simple and can be implemented at low cost.

In the front differential 301, as in the second embodiment, the support portions 339 and 341 are connected to the pinion gear 31.
You may comprise by the recessed part according to the tooth tip curvature of 9,321.

Further, even if the supporting portion is a concave portion corresponding to the curvature of the addendum of the pinion gear or a cylindrical portion, the ring member on which these are formed is the boss of the side gear as in the second embodiment. It may be attached to the part.

[Fourth Embodiment] A front differential 401 (fourth embodiment: a differential device) will be described with reference to FIG. In addition, the left and right directions in the figure indicate the vehicle using the front differential 401 and the left and right directions in FIG. 7.

The front diff 401 is used in a vehicle using the front diff 1 of the first embodiment in place of the front diff 1. The members having the same functions as the front diff 1 are designated by the same reference numerals. However, the differences will be described.

Left and right output side helical side gears 403 and 405 are arranged inside the differential case 3. The side gears 403 and 405 are provided with hollow boss portions 407 and 409, respectively, which extend inward in the axial direction.

Side gears 403, 405 (boss portion 40
7, 409) is rotatably supported by the support portions 23, 25 of the differential case 3 (casing body 7), and is supported by a support portion 410 provided between the boss portions 407, 409 on the inner side in the axial direction. It fits and is centered.

The left and right front axles 411, 412 are splined to the side gears 403, 405, and a thrust washer 413 is arranged between the side gear 403 (boss portion 407) and the side gear 405.

In the differential case 3 (casing body 7), four sets of accommodating holes 415, 417 of equal length are formed at equal intervals in the circumferential direction. Helical pinion gears 419 and 421 are slidably and rotatably housed in these housing holes 415 and 417, respectively.

The pinion gear 419 comprises a first gear portion 423 and a second gear portion 425, and the first gear portion 423 meshes with the right side gear 405. The other pinion gear 421 includes a first gear portion 427 and a second gear portion 429, the first gear portion 427 meshes with the left side gear 403, and the second gear portion 429 includes the side gears 403, 40.
Axial inner side of 5 (radial outer side of bosses 407 and 409)
Thus, it meshes with the second gear portion 425 of the pinion gear 419.

Thrust washers 431 that prevent the pinion gears 419 and 421 from falling out from the receiving holes 415 and 417 are fixed to the boss portions 29 and 31 of the differential case 3 by snap rings 433, respectively.

A cylindrical support portion 435 is provided on the outer periphery of the boss portion 407 of the side gear 403 to support the pinion gears 419 and 421 on the side of the second gear portions 425 and 429.

The driving force of the engine 1 for rotating the differential case 3 is from the pinion gears 419 and 421 to the side gear 4
03, 405 are distributed to the left and right front wheels, and if one of the front wheels idles on a bad road or the like, the driving force of the engine is differentially distributed to the left and right front wheels as the pinion gears 419, 421 rotate. It

During the transmission of torque, the pinion gear 41
The tooth tips of 9, 421 are pressed against the cylindrical wall surfaces of the accommodating holes 415, 417 by the reaction force of engagement with the side gears 403, 405 and the centrifugal force, and sliding resistance is generated.

The right and left end faces of the pinion gears 419 and 421 are pressed against the thrust washers 431 by the meshing thrust force of the helical gears, and the left and right end faces of the pinion gears 419 and 421 are respectively attached to the casing body 7 (the housing Sliding resistance is generated by being pressed against the left end surface and the right end surface of the holes 415, 417, and further, between the side gears 403, 405 and the cover 5 and the casing body 7, and through the thrust washer 413, the side gear 403. , 405, a sliding resistance is generated.

A torque sensitive type differential limiting function is obtained by these sliding resistances.

The cover 5 of the differential case 3 and the casing body 7 are provided with openings 437 and 439 through which the accommodation holes 415 and 417 pass, respectively, and the oil scraped up by the differential case 3 (ring gear) is It flows into the differential case 3 through the openings 437 and 439, and the accommodation hole 4
15, 417 and pinion gears 419, 421 sliding portion, side gear 403 (boss portion 407) support portion 435.
Lubricates and cools the sliding portion between the pinion gears 419 and 421, the thrust washer 413, the meshing portion of each gear, and the like.

In this way, the front differential 401 is constructed. The front diff 401 has side gears 403, 4
05 axially inward, the boss portion 407 of the side gear 403.
The side gears 403, 405 and the pinion gears 419, 421 are configured to support each other by supporting the pinion gears 419, 421 by the support portion 435 provided on the cover 5. Only 437 is formed, and the support portion 23 of the side gear 403 is not formed.

Therefore, it is not necessary to subject the cover 5 to a surface hardening treatment for imparting a large amount of abrasion resistance to the support portion 23, and an increase in cost due to the surface hardening treatment can be avoided.

Further, since the petal-shaped recess formed by the support portion 23 is also eliminated, the processing cost of the cover 5 is greatly reduced and the surface hardening treatment is not performed.
In addition to the petal-shaped recess, machining of the flange portion 9 that abuts the flange portion 10 of the casing body 7 and machining of the engaging portion 11 that engages with the casing body 7 are facilitated,
The processing cost is further reduced.

The support portion 435 is attached to the side gear 403.
Since it is formed integrally with the (boss portion 407), the number of parts is reduced, and the supporting portion 435 having a cylindrical outer periphery is extremely easy to process and can be implemented at low cost.

In the case of the front differential 401, the second
As in the embodiment, the ring member may be attached to the boss portion of the side gear.

In the differential gear of the present invention, the pinion gear and the side gear are not limited to helical gears, but may be spur gears (spur gears).

Further, the differential device of the present invention is
Not only front diff, but also rear diff (differential device that distributes the driving force of the engine to the left and right rear wheels) and center diff (differential device that distributes the driving force of the engine to the front and rear wheels).

[0095]

According to the differential device of the present invention, the support portion of the side gear supports the pinion gear, and the side gear and the pinion gear support each other, so that the case member on the support portion side supports the side gear and the pinion gear. It is not necessary to provide a housing hole for the case, and it is not necessary to process the petal-shaped recess formed of the supporting portion and the housing hole in this case member. Therefore, the processing cost is greatly reduced and the supporting portion and the housing hole are large. It is no longer necessary to subject the case member to a surface hardening treatment to provide abrasion resistance, the cost increase due to the surface hardening treatment is avoided, and the machining of mating surfaces is facilitated and the processing cost is further reduced. .

The differential device according to the second aspect can obtain the same effect as that of the configuration according to the first aspect.

The differential device according to claim 3 can obtain the same effect as that of the structure according to claim 1.

The differential device of the fourth aspect can obtain the same effect as that of the structure of the first aspect.

The differential device according to the fifth aspect can obtain the same effects as those of the configurations according to the first to fourth aspects.

A ring member having a cylindrical outer periphery is extremely easy to process and can be implemented at low cost.

Further, if the surface hardening treatment is applied only to the ring member which is separate from the boss portion of the side gear, the differential device according to the sixth aspect can obtain the same effect as that of the fifth or sixth aspect. .

Further, by integrating the ring member with the boss portion of the side gear, the number of parts and the parts cost can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view of a first embodiment.

FIG. 2 is a view on arrow A in FIG.

FIG. 3 is a view showing a thrust washer used in the first embodiment.

FIG. 4 is a cross-sectional view showing the main parts of the second embodiment.

FIG. 5 is a view showing a ring used in the second embodiment.

FIG. 6 is a sectional view of a third embodiment.

FIG. 7 is a sectional view of a fourth embodiment.

FIG. 8 is a sectional view of a conventional example.

[Explanation of symbols]

1 Front Differential (Differential Device) 3 Differential Case 5 Cover (Case Member) 9 Flange Part of Cover 5 11 Engagement Part 15, 17 between Cover 5 and Casing Body 7 Output Side Helical Side Gear 19 Boss Part 23 of Side Gear 15 For Side Gear 15 Support portions 49, 51 of the pinion gears 53, 55 accommodation holes 53, 55 helical pinion gear (pinion gear set) 57 first gear portion 59 second gear portion 61 cylindrical support portion 101 provided on the boss portion 19 ring (Ring member) 103 Cylindrical support portion 301 provided on the ring 101 Front differential (differential device) 303, 305 Output side helical side gears 307, 309 Side gears 303, 305 boss portions 315, 317 Pinion gears 319, 321 accommodation Holes 319, 321 helical pinio Gear (pinion gear set) 323, 331 first gear portion 325, 327, 333, 335 second gear portion 339, 341 cylindrical support portion 401 provided on boss portions 307, 309 front differential (differential device) 403, 405 Output side helical side gears 407, 409 Boss portions 415, 417 of side gears 403, 405 Housing holes 419, 421 of pinion gears 419, 421 Helical pinion gears (pinion gear group) 423, 427 First gear portions 425, 429 Second gears Portion 435 Cylindrical support portion provided on the boss portion 407

Claims (6)

[Claims] 1. A differential case rotationally driven by a driving force of a prime mover, a pair of output side gears rotatably supported inside the differential case, a second gear portion meshing with each other, and a first gear portion forming the side gears. A pinion gear set that connects the side gears by meshing with each other, and a storage hole that slidably and rotatably stores the pinion gears, and at least one of the side gears in at least one of the axial direction. A differential device characterized in that a support portion for supporting the outer periphery of the pinion gear is provided on one boss portion. 2. The invention according to claim 1, wherein the second gear portion of the pinion gear meshes with either of the axial outer sides of the both side gears, and the outer periphery of the pinion gear. A support portion for supporting the second
A differential device, wherein the differential device is provided so as to face the meshing portion side of the gear portion. 3. The invention according to claim 1, wherein the second gear portions of the pinion gear mesh with each other on both axial outer sides of the both side gears and support the outer periphery of the pinion gear. The support portion is the second
A differential device, wherein the differential device is provided so as to face each of the meshing portions of the gear portion. 4. The invention according to claim 1, wherein the second gear portion of the pinion gear meshes with each other on the inner side in the axial direction of the both side gears and supports the outer periphery of the pinion gear. The second part
A differential device, wherein the differential device is provided so as to face the meshing portion side of the gear portion. 5. The invention according to any one of claims 1 to 4, wherein a ring member is fixed to the boss portion of the side gear, and a support portion that supports an outer periphery of the pinion gear is the A differential device comprising a cylindrical portion provided on a ring member. 6. The differential device according to claim 5, wherein the ring member is formed integrally with a side gear.