JPH0979351A - Differential gear - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stabilize initial torque while obtaining the amplifying effect for initial torque met for a teeth ratio between a side gear and a pinion gear. SOLUTION: A differential gear comprises a differential case 3 rotationally driven by an engine, side gears 19 and 21 on the output side rotationally supported at the interior thereof, at least a pair of pinion gears 45 and 47 to intercouple the gears 19 and 21, containing holes 41 and 43 slidably and rotatably containing the gears 45 and 47, an annular slide member 71 arranged opposite to the end face of one or both of the gears 45 and 47 of each pair, and an integral annular disc spring 69 to press the slide member 71 against the end face and exert frictional torque.

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 FIG. 9 is disclosed in Japanese Patent Publication No. 47-51375.
A differential device 201 such as 10 is described.

This differential device 201 includes a differential gear case 209 having a ring gear 203 and two end plates 205 and 207 fixed to each other, and side gears 211 and 21 on the output side.
3, a pair of pinion gears 215, 21 meshing with each other
6 sets of 7 pinion gears, each pinion gear 21
5 and 217 are arranged one by one, and these are defcase 2
It is equipped with disc springs 219, 221 and the like that press against 09.

The pinion gears 215 and 217 are slidably and rotatably supported by the differential case 209.
11, 213 are connected.

The driving force of the engine for rotating the differential case 209 is transmitted from the pinion gears 215, 217 to the wheel side through the side gears 211, 213, and if a driving resistance difference occurs between the wheels on a bad road, etc. The driving force is differentially distributed to each wheel side by the rotation of the pinion gears 215 and 217.

At this time, the differential limiting force is generated by the frictional resistance generated between each gear and the differential case 209.

In addition to this, a constant initial torque (differential limiting torque) is obtained by the frictional resistance generated between the pinion gears 215 and 217 and the differential case 209 by the pressing force of the disc springs 219 and 221. This initial torque greatly improves the ability of the vehicle to escape from a rough road.

If, for example, the number of teeth Z1 of the side gears 211, 213 is 20 and the number of teeth Z2 of the pinion gears 215, 217 is 6, the initial torque T (= of the pinion gears 215, 217 by the disc springs 219, 221) is set. (Braking force) is amplified by Z1 / Z2 = 20/6 3.33 times, which is advantageous because a large initial torque is obtained as a whole.

[0009]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
9, 221 are pinion gears 215, 2 as described above.
17 (12 for differential device 201)
Used only. Thus, the disc springs 219, 22
When the number of 1 is large, the spring force varies between the disc springs 219 and 221 and the initial torque becomes unstable.

Therefore, an object of the present invention is to provide a differential device which stabilizes the initial torque while obtaining the effect of amplifying the initial torque by the gear ratio of the side gear and the pinion gear.

[0011]

A differential device according to a first aspect of the present invention comprises a differential case which is rotationally driven by a driving force of an engine, and a pair of output side gears which are rotatably supported inside the differential case. At least one pair of pinion gears, which are arranged radially outside of the side gears, have a first gear portion and a second gear portion that mesh with the side gears, and a pair of pinion gears that are formed on the differential case and slidably and rotatably accommodate the respective pinion gears. A hole, a ring-shaped sliding member arranged so as to face one or both end surfaces of each pair of pinion gears, and an integral ring-shaped disc spring that presses the sliding member against the end surface to give a friction torque. It is characterized by having.

The driving force of the engine for rotating the differential case is distributed from the pinion gears to the wheels via the side gears, and when a driving resistance difference occurs between the wheels while traveling on a rough road, the engine of the pinion gear is rotated. Driving force is distributed differentially to each wheel side.

While transmitting the torque in this way,
Friction resistance is generated by the meshing reaction force of the pinion gears and the meshing thrust force in the case of the helical gear configuration, and these frictional resistances provide a torque sensitive differential limiting function.

Further, due to the frictional resistance generated between the sliding member and the pinion gear due to the pressing force of the disc spring, in addition to the torque sensitive differential limiting function, a constant constant differential limiting force (initial torque) is obtained. To be As described above, this initial torque is amplified by the gear ratio between the pinion gear and the side gear, and becomes a large initial torque.

In addition to this, unlike the conventional example in which a disc spring is arranged for each pinion gear, in the present invention, the one side end face of each pinion gear is configured to press the pinion gear with an integral disc spring. There is no variation in the spring force of the spring. In this way, fluctuations in the initial torque are eliminated and stable differential limiting characteristics are obtained.

A differential device according to a second aspect is the differential device according to the first aspect, wherein the differential case is
A casing having a casing main body and a cover, and the cover provided with a sliding member and a disc spring accommodating portion.
Similar to the differential device described above, the effect of amplifying and stabilizing the initial torque can be obtained.

In addition to this, since the sliding member and the accommodation portion for the disc spring are formed on the cover side, it is possible to avoid that only one of the cover and the casing main body becomes particularly complicated in shape, and the processing cost is reduced. It is advantageous for reduction.

Furthermore, by providing the storage portion on the cover side, the depth of the storage portion can be arbitrarily changed without being restricted by the axial length of the pinion gear, and the disc spring can be changed by changing the depth. The initial torque can be adjusted to a desired strength by adjusting the preload of the.

A differential device according to a third aspect is the differential device according to the first aspect, wherein the differential case is
A casing main body and a cover are provided, and the casing main body is provided with a sliding member and a disc spring storage portion.
Similar to the differential device according to the first aspect, the effect of amplifying and stabilizing the initial torque can be obtained.

In addition to this, since the housing portion for the sliding member and the disc spring is formed on the casing body side, it is not necessary to process the cover side for the housing portion. Therefore, the contact surface of the cover that comes into contact with the disc spring can be made flat, and in the case of the helical gear configuration, the meshing thrust force of the pinion gear is evenly applied to this contact surface, and the initial torque is stabilized.

A differential device according to a fourth aspect is the differential device according to any one of the first to third aspects, in which the support portion of the pinion gear provided on the differential case is
One or both of the sliding member and the disc spring are supported on the inner circumference or the outer circumference, and the effect of amplifying and stabilizing the initial torque can be obtained as in the differential device according to the first to third aspects.

In addition to this, by providing the supporting portion on the differential case, the sliding member and the disc spring can be easily assembled, the postures of the sliding member and the disc spring are stabilized, and catching can be prevented. The torque is stable.

Further, if the sliding member or the disc spring is engaged with the support portion in the rotation direction to prevent the rotation, the sliding member or the disc spring is prevented from generating heat or being worn, so that it is stable for a long period of time. The initial torque is obtained. In particular, if the disc spring is prevented from rotating, abnormal wear due to line contact at the end of the disc spring is prevented, and durability is greatly improved.

A differential device according to a fifth aspect of the present invention is the differential device according to any one of the first to fourth aspects, in which the pair of pinion gears interferes with a side gear that meshes with the mating pinion gear between the first and second gear portions. It has a small diameter shaft part to avoid, each second gear part consists of a pair of equal length pinion gears that mesh on both axial sides of both side gears, and both end faces of all pinion gears are slidable with disc springs arranged on each end face side. It is configured to be pressed via the moving member, and as in the differential device according to the first to fourth aspects, the effect of amplifying and stabilizing the initial torque can be obtained.

In addition to this, when each gear is composed of a helical gear, the direction of the meshing thrust force received by the pinion gear changes depending on which side gear side wheel idles. With a symmetrical configuration in which each disc spring presses the surface separately via the sliding member, even if any wheel idles (whether the meshing thrust force of the pinion gear is in any direction), a uniform difference A motion limiting characteristic is obtained.

This characteristic is suitable for a differential device (front differential and rear differential) that distributes the driving force of the engine to the left and right wheels.

A differential device according to a sixth aspect is the differential device according to any one of the first to fourth aspects, wherein the pair of pinion gears has a short pinion gear having no shaft portion between the first and second gear portions. It consists of a long pinion gear having a small-diameter shaft portion between the first and second gear portions that avoids interference between the short pinion gear and the meshing side gear, and the disc springs slide on the end faces of the second gear portion of all the pinion gears. It is configured so as to be pressed via the, and similar to the differential device according to the first to fourth aspects, the effect of amplifying and stabilizing the initial torque can be obtained.

In addition to this, when each gear is composed of a helical gear, as described above, in the asymmetric structure in which the disc spring and the sliding member are arranged only on the end face (one end side) of the pinion gear on the second gear portion side. Different differential limiting characteristics are obtained depending on whether the meshing thrust force of the pinion gear pushes back the disc spring force or vice versa.

This characteristic is that a differential device (center-diff) for distributing the driving force of the engine to the front wheels and the rear wheels.
Is a characteristic suitable for.

Further, only by disposing the disc spring and the sliding member at one end of the pinion gear, it is possible to adjust the differential limiting characteristic at a low cost without making a great modification.

A differential device according to claim 7 is the differential device according to any one of claims 1 to 6, wherein each gear is a helical gear, and like the differential device according to claims 1 to 6, the initial torque is changed. An amplification effect and a stabilization effect can be obtained.

In addition to this, as in the structure of claim 6,
It is possible to adjust the differential limiting characteristics unevenly.

[0033]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to FIGS. This embodiment is claimed in claims 1, 3, 4,
It has the features of 5 and 7, and FIG. 1 shows a differential device 1 of this embodiment. Note that the left and right directions are the left and right directions in FIG. 1, and the members and the like without reference numerals are not shown.

The differential device 1 is arranged on the axle of the front wheel or the rear wheel of the vehicle.

As shown in FIG. 1, the differential case 3 of the differential device 1 is provided with covers on both left and right sides of the casing body 5.
7 and 9 are fixed by bolts 11 and 13.
A ring gear is fixed to the differential case 3, and the ring gear meshes with an output gear of a power transmission system that transmits the driving force of the engine. Thus, the differential case 3 is driven to rotate by the driving force of the engine.

The differential device 1 is arranged inside the differential carrier, and the boss portions 15 and 1 of the differential case 3 are provided.
7 is supported by the differential carrier via a bearing. The differential carrier is provided with an oil sump. The lower part of the differential device 1 is immersed in the oil sump in a stationary state, and repels the oil from the oil sump when rotated.

Inside the differential case 3, output side gears 19 and 21 each composed of a helical gear are arranged.

Hollow boss portion 2 of each side gear 19, 21
Numerals 3 and 25 are rotatably supported by bearings 27 and 29 of the differential case 3. Thrust blocks 35 are arranged on the large diameter portions 31 and 33 formed inside the boss portions 23 and 25 so as to straddle the inner circumferences of the large diameter portions 31 and 33.
Each free end 21 is supported and centered.

The boss portion 23 of the side gear 19 is spline-connected to the left axle (output shaft), and the boss portion 25 of the side gear 21 is spline-connected to the right axle (output shaft). These axles are attached to each other via a thrust block 35.

Thrust washers 37 are arranged between the side gears 19 and 21 and the differential case 3, respectively, and between the side gears 19 and 21 (outer peripheral side of the thrust block 35).
A thrust washer 39 is arranged in the.

As shown in FIGS. 1 and 2, the differential case 3 has three sets of storage holes 41 and 43 formed in the circumferential direction. Storage hole 4
Pinion gears 45 and 47 of equal length, which are helical gears, are housed in 1 and 43 so as to be slidably rotatable.

The one pinion gear 45 includes a first gear portion 49, second gear portions 51 and 53, and a small-diameter shaft portion 55 that connects the first and second gear portions 49 and 53.
The gear portion 49 meshes with the side gear 19. The other pinion gear 47 includes a first gear portion 57, second gear portions 59 and 61, and a small-diameter shaft portion 63 that connects the first and second gear portions 57 and 59. The portion 57 meshes with the side gear 21, and the second gear portions 59 and 61 mesh with the second gear portions 51 and 53 of the pinion gear 45, respectively.

Ring-shaped storage portions 65 and 67 communicating with the storage holes 41 and 43 are formed on both left and right sides of the casing body 9 of the differential casing 3. These storage parts 65, 6
7, a ring-shaped disc spring 69 is housed on the outside and a ring-shaped washer 71 (sliding member) is housed on the inside. The washer 71 uses the disc spring 69 to move the pinion gears 45,
It is pressed against both end faces of 47.

The cover holes 7 and 9 are provided with storage holes 41 and 43.
Support portions 73, 7 of the pinion gears 45, 47 forming a part of
5 is formed, and the washer 71 is engaged with the respective support portions 73 and 75 by the engagement portion 77 on the inner peripheral side shown in FIG.

The driving force of the engine for rotating the differential case 3 is from the pinion gears 45 and 47 to the side gears 19 and 2.
It is distributed to the left and right wheels via 1, and when driving on a rough road,
When a driving resistance difference occurs between the wheels, each pinion gear 45, 4
By the rotation of 7, the driving force of the engine is differentially distributed to the left and right wheels.

During transmission of torque, each pinion gear 45, 4
The tooth tip of 7 is pressed against the wall surfaces of the housing holes 41 and 43 by the reaction force of meshing with the side gears 19 and 21, and frictional resistance is generated. Further, the mesh thrust force of the helical gear causes frictional resistance between the pinion gears 45 and 47 and the washer 71, and the side gears 19 and 21 and the differential case 3 via the thrust washer 37.
In addition, the side gears 19, 2 are inserted through the thrust washers 39.
Friction resistance occurs in each of the 1 and 2.

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

Further, the pressing force of the disc spring 69 causes a frictional resistance between the washer 71 and both end faces of the pinion gears 45 and 47. Due to this frictional resistance, a constant differential limiting force (initial torque) is always obtained in addition to the torque sensitive differential limiting function.

This initial torque is amplified by the gear ratio between the pinion gear and the side gear, and becomes a large initial torque.

As shown in FIG. 1, the differential case 3 has an opening 7
9, 81 are provided, and spiral oil grooves 83, 85 are formed on the inner periphery of the boss portions 15, 17.

When the differential device 1 is stationary, the oil immersed in the openings 79, 81 and the oil grooves 83, 85 flows into the differential case 3, and when the differential device 1 rotates, the oil splashes from the oil sump. The oil that has been lifted up and bounces off the inner wall of the differential carrier causes the opening 79,
The oil flows into the diff case 3 from 81, the oil grooves 83, 85 and the like.

The oil that has flowed in contains the storage holes 41 and 43, the meshing portions of the gears, the sliding portions that generate the torque-sensitive differential limiting force, and the washers 71 that generate the initial torque.
Is supplied to the sliding surface between the pinion gears 45 and 47,
Lubricate these. The oil in the oil grooves 83, 85 is sent to the bearings 27, 29 of the side gears 19, 21 and the thrust washers 37 by the rotation of the differential case 3,
Lubricate these.

Thus, the differential device 1 is configured.

In the vehicle equipped with the differential device 1, the behavior of the vehicle body when a large torque is applied such as at the time of starting or accelerating is improved by the torque sensitive differential limiting function. Further, when the one side wheel spins on a bad road or the like, the driving force is sent to the other side wheel by the stable initial torque as described above, and the bad road escape property is greatly improved.

Further, in the differential device 1, unlike the conventional example in which the disc spring is arranged for each pinion gear as described above, the washer 71 is pressed against both end faces of each pinion gear 45, 47 by the integral disc spring 69. Configured to do so. In this way, fluctuations in the initial torque due to variations in the spring force of the disc springs are eliminated, and stable differential limiting characteristics are obtained.

Further, since each gear is composed of a helical gear, the meshing thrust force direction of the helical gears received by the pinion gears 45 and 47 changes depending on which of the left and right wheels is idling, but as described above, all the pinion gears 4
5 and 47 have disc springs 69 and washers 71 on both end faces, respectively.
In the left-right symmetric configuration in which and are arranged, even if any wheel idles (the meshing thrust force is in any direction), left-right uniform differential limiting characteristics can be obtained.

This characteristic is suitable for the front differential and the rear differential, which distribute the driving force of the engine to the left and right wheels.

In addition to this, the washer 71 and the disc spring 69
Since the storage portions 65 and 67 of the above are formed on the side of the casing main body 5, the covers 7 and 9 do not require processing for the storage portions. Therefore, the contact surface 87 of the cover that contacts the disc spring 69.
Can be made flat, the meshing thrust force of the pinion gears 45, 47 is evenly applied to the contact surface 87, and the initial torque is stabilized.

Further, the washers 71, which are prevented from rotating by the support portions 73 and 75 of the covers 7 and 9, are prevented from generating heat and abrasion due to their rotation and sliding, and thus are stable for a long period of time. Initial torque can be obtained.

Further, by providing the supporting portions 73 and 75, the washer 71 can be easily assembled and the washer 7 can be easily assembled.
The posture of No. 1 is stable, catching is prevented, and the initial torque is stable. Further, even if the disc spring 69 is prevented from rotating by the supporting portions 73 and 75, the same effect can be obtained.

Next, a second embodiment of the present invention will be described with reference to FIGS. This embodiment is defined in claims 1, 2, 6,
It has 7 features. Further, members and the like not given reference numerals are not shown.

The differential device of this embodiment has four
It is used as the center differential 89 of a wheel drive vehicle.

As shown in FIG. 3, the differential case 91 of the center differential 89 is constructed by fixing the casing body 93 and the cover 95 with bolts 97. The driving force of the engine rotationally drives the differential case 91 via the transfer.

The center differential 89 is arranged inside the transfer case. The transfer case is provided with an oil sump, and the lower part of the center differential 89 is immersed in this oil sump in a stationary state, and when rotated, splashes oil from the oil sump.

Inside the differential case 91, output side gears 99 and 101 composed of helical gears are arranged.

The side gears 99 and 101 are formed integrally with the hollow output shafts 103 and 105, respectively.
Reference numeral 05 is rotatably supported by support portions 107 and 109 of the differential case 91. The side gears 99 and 101 are centered with their free ends supported by bearings 111 provided between them.

The output shaft 103 is connected to the rear wheels from the power transmission system on the rear wheel side via the rear differential, and the output shaft 105 is connected to the front wheels from the power transmission system on the front wheel side via the front differential.

Side gears 99 and 101 and differential case 91
Thrust washers 113 and 115 are disposed between the side gears 99 and 101, and a thrust washer 117 is disposed between the side gears 99 and 101.

A plurality of sets of storage holes 11 are provided in the differential case 91.
9 and 121 are formed in the circumferential direction, and long and short pinion gears 123 and 125, which are helical gears, are slidably and rotatably housed in the housing holes 119 and 121.

The long pinion gear 123 includes the first and second gear portions 127, 129 and the small-diameter shaft portion 1 connecting them.
The first gear portion 127 meshes with the side gear 99. Further, the short pinion gear 125 has the first and second gear parts 133, 13 having no shaft part between them.
The first gear portion 133 meshes with the side gear 101, and the second gear portion 135 includes the second gear portion of the pinion gear 123.
It meshes with the gear portion 129.

As shown in FIG. 4, the cover 95 of the differential case 91 is formed with a ring-shaped storage portion 137 facing the storage holes 119 and 121. As shown in FIG. 5, a ring-shaped disc spring 139 is housed outside and a ring-shaped washer 141 (sliding member) is housed inside the housing 137. The washer 141 is pressed against the right end faces of the pinion gears 123 and 125 by the disc spring 139.

As shown in FIG. 4, the cover 95 is formed with a circumferential portion 143 (support portion), and the washer 141 and the disc spring 139 are supported by the circumferential portion 143 on the inner circumference. .

The driving force of the engine for rotating the differential gear 91 is from the pinion gears 123 and 125 to the side gear 9
It is distributed to the rear wheels and the front wheels via 9, 101. Also, for example, when a driving resistance difference occurs between the front and rear wheels during traveling on a rough road, the driving force of the engine is differentially distributed to each wheel side by the rotation of each pinion gear 123, 125.

During transmission of torque, each pinion gear 123,
The tooth tips of 125 are pressed against the wall surfaces of the housing holes 119 and 121 by the reaction force of meshing with the side gears 99 and 101, so that frictional resistance is generated. Further, due to the meshing thrust force of the helical gears, between the left end surfaces of the pinion gears 123 and 125 and the differential case 91, and between the pinion gears 12
Frictional resistance is generated between the right end surfaces of the Nos. 3, 125 and the washer 141, and the thrust washers 113, 115
Between the side gears 99 and 101 and the differential gear case 91, and through the thrust washer 117.
Friction resistance occurs between 9 and 101.

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

Further, the pressing force of the disc spring 139 causes frictional resistance between the washer 141 and the side gears 99 and 101. This frictional resistance provides an initial torque in addition to the torque-sensitive differential limiting function.

This initial torque is amplified by the gear ratio of the pinion gear and the side gear, and becomes a large initial torque.

The differential case 91 is provided with openings 145, 147. The opening 145, 145 is provided inside the differential case 91 regardless of whether the center differential 89 is rotating or stopped.
The oil inflows from 147, and the inflowing oil receives the storage holes 119 and 121, the meshing parts of the gears, the sliding parts that generate a torque-sensitive differential limiting force, the washers 141 that generate the initial torque, and the pinion gear 123. , 125 to be supplied to the sliding surface and the like to lubricate them.

In this way, the center differential 89 is constructed.

In the vehicle equipped with the center differential 89, the behavior of the vehicle body when a large torque is applied such as at the time of starting or accelerating is improved by the torque sensitive differential limiting function. Also, when one of the front and rear wheels spins on a bad road,
The driving force is sent to the other wheel by the stable initial torque as described above, and the ability to escape from a rough road is greatly improved.

Further, in the center differential 89, unlike the conventional example in which the disc springs are arranged for each pinion gear, as described above, the disc springs 139 are integrated into the pinion gears 123,
Since the washer 141 is configured to be pressed against the end surface of the 125, fluctuations in the initial torque due to variations in the spring force of the disc spring are eliminated, and stable differential limiting characteristics can be obtained.

Further, since the center differential 89 is composed of a helical gear, the direction of the meshing thrust force received by the pinion gears 123 and 125 changes depending on which of the front and rear wheels idles. As described above, each pinion gear 12
The disc spring 139 and the washer 1 are provided only on one end face of the 3, 125.
In the left-right asymmetrical configuration in which 41 and 41 are arranged, the meshing thrust force received by the pinion gears 123 and 125 changes in the same direction and in the opposite direction as the force of the disc spring, so that the front wheels idle and the rear wheels idle. And have different differential limiting characteristics.

FIG. 6 is a graph showing the differential limiting characteristics of the center differential 89. The 45 ° graph 149 is the characteristic of the differential device having no differential limiting force.
Graphs 151 and 153 are differential limiting characteristic graphs of the center differential 89. These graphs 151 and 153 are equiangular with respect to this graph 149. The graph 151 shows the drive torque sent to the front wheels when the rear wheels idle,
The graph 153 shows the driving torque sent to the rear wheels when the front wheels run idle. The intersection of the vertical axis and the horizontal axis of each of the graphs 151 and 153 is the initial torque Ti described above.

When one of the rear wheels and the front wheels completely idles, the driving torque of the grip side wheels becomes zero according to the characteristic of the graph 149, while the center differential 89 shows the graph 15.
As in Nos. 1 and 153, the initial torque Ti is sent to the grip side wheels, and the rough road running performance is greatly improved.

Further, the graph 155 is a graph which is line-symmetrical to the graph 153 with respect to the graph 149, and the graph 151 is a parallel translation of the graph 155. This connects the center differential 89 to the pinion gear 123, as described above.
125 Belleville spring 139 and washer 141 only on one end face
This is because the front and rear are asymmetrical in that and are arranged, and when one side idles, a large torque is sent to the rear wheel side compared to the front wheel side.

This characteristic is suitable for a center differential.

Further, as described above, only by disposing the disc spring 139 and the washer 141 at one end of the pinion gears 123 and 125, it is possible to adjust such a differential limiting characteristic at a low cost without major modification. Will be possible.

Further, in the center differential 89, the disc spring 13
9 and the washer 141 are formed in the cover 95 so that only one of the cover 95 and the casing main body 93 has a complicated shape as compared with the case where the housing main body 93 is provided with the storage portion. This is advantageous in reducing the processing cost.

By forming the storage portion 137 in the cover 95, the depth of the storage portion 137 can be arbitrarily changed without being restricted by the lengths of the pinion gears 123 and 125, as shown in FIG. The initial torque can be adjusted to a desired strength by changing the depth and adjusting the preload of the disc spring 139.

Further, since the circumferential portion 143 for supporting the disc spring 139 and the washer 141 is provided, the disc spring 139 is provided.
And the washer 141 are easily assembled, and the disc spring 13
The postures of 9 and the washer 141 are stable, the catching is prevented, and the initial torque is stable.

Next, a third embodiment of the present invention will be described with reference to FIGS. This embodiment has the features of claims 1, 3, 6, and 7, and FIG. 7 shows a differential device (center-diff 157) of this embodiment.

Differences from the center differential 89 of the second embodiment will be described below.

The center differential 157 is a disc spring 139 provided on the cover 95 at the center differential 89.
The housing portion 137 of the washer 141 and the washer 141 is formed in the casing body 93. Therefore, the cover 95 has a circumferential portion 143 supporting the disc spring 139 and the washer 141.
Is not formed. Other configurations are center differential 8
Same as 9.

In this way, since the housing portion 159 for the disc spring 139 and the washer 141 is formed in the casing body 93, the cover 95 does not require any processing for the housing portion.
The contact surface 161 of the cover 95 that contacts the disc spring 139 can be flattened. Therefore, the pinion gear 123,
The meshing thrust force of 125 is evenly applied to this contact surface 161, and the initial torque is stabilized.

In the present invention, the pinion gear and the side gear may be constituted by spur gears instead of helical gears. In the case of the spur gear, since the differential limiting force due to the meshing thrust force is not generated, the ratio of the initial torque to the total differential limiting force increases. Therefore, the effect of the present invention which amplifies and stabilizes the initial torque becomes particularly remarkable in the differential device constituted by the spur gear.

Further, in the present invention, the pair of pinion gears may be equal length pinion gears in which the second gear portion meshes inside the side gear. In this case, the disc spring and the sliding member may be arranged, for example, at the end of the pinion gear on the first gear portion side.

As described above, in the differential device of the present invention, when the disc spring and the sliding member are arranged at both ends of the pinion gear, the front differential (the differential device arranged on the front wheel axle) or It is suitable for a rear differential (a differential device arranged on the axle on the rear wheel side). Further, the configuration in which the disc spring and the sliding member are arranged at one end of the pinion gear is suitable for a center differential (a differential device that distributes the driving force of the engine to the front wheel side and the rear wheel side).

[0098]

According to the differential device of claim 1,
Due to the frictional resistance generated between the sliding member and the pinion gear due to the pressing force of the disc spring, an initial torque is obtained in addition to the torque-sensitive type differential limiting function. This initial torque is amplified by the tooth number ratio of the pinion gear and the side gear to become a large initial torque.

Further, unlike the conventional example in which the disc spring is arranged for each pinion gear, in the present invention, since the end face of each pinion gear is pressed by the integral disc spring, the initial torque due to the variation of the spring force is Fluctuations are eliminated,
Stable differential limiting characteristics can be obtained.

The differential device according to the second aspect can obtain the amplifying effect and the stabilizing effect of the initial torque, similarly to the differential device according to the first aspect.

In addition to this, by forming the sliding member and the storage portion for the disc spring on the cover side, it is possible to avoid that only one of the cover and the casing main body becomes particularly complicated in shape.
It is advantageous in reducing the processing cost.

Further, by providing the storage portion in the cover, the depth of the storage portion can be arbitrarily changed without being restricted by the length of the pinion gear, and the depth of the disk spring can be changed by changing the depth. By adjusting the pressure, the desired initial torque is obtained.

The differential device according to the third aspect can obtain the amplifying effect and the stabilizing effect of the initial torque similarly to the differential device according to the first aspect.

In addition to this, since the housing portion for the sliding member and the disc spring is formed on the casing body side, and the cover side processing for the housing portion is not required, the cover which contacts the disc spring is not necessary. The contact surface can be made flat, and in the case of the helical gear configuration, the meshing thrust force of the pinion gear is evenly applied to this contact surface, and the initial torque is stabilized.

The differential device according to the fourth aspect can obtain the amplifying effect and the stabilizing effect of the initial torque, similarly to the differential device according to any one of the first to third aspects.

In addition to this, by providing the supporting portion on the differential case, it becomes easy to assemble the sliding member and the disc spring, and the postures of the sliding member and the disc spring are stabilized, and catching is prevented. , The initial torque is stable.

Further, if the sliding member and the disc spring are prevented from rotating by this supporting portion, heat generation and wear due to sliding can be prevented, and a stable initial torque can be obtained for a long period of time. In particular, if the disc spring is prevented from rotating, abnormal wear due to line contact with the end of the disc spring is prevented, and durability is greatly improved.

According to the differential device of the fifth aspect, similar to the differential device of any of the first to fourth aspects, the effect of amplifying and stabilizing the initial torque can be obtained.

In addition to this, even in the case of the helical gear structure, even if any of the wheels idles, a uniform differential limiting characteristic can be obtained, and a characteristic suitable for the front differential and the rear differential can be obtained.

According to the differential device of the sixth aspect, similar to the differential device of any of the first to fourth aspects, an amplifying effect and a stabilizing effect of the initial torque can be obtained.

In addition to this, if each gear is composed of a helical gear, different differential limiting characteristics can be obtained depending on the idling wheels, and characteristics suitable for center differential can be obtained. Only by disposing the disc spring and the sliding member at one end of the pinion gear, it is possible to adjust the differential limiting characteristic at a low cost without making a large modification.

According to the differential device of the seventh aspect, similar to the differential device of any of the first to sixth aspects, the effect of amplifying and stabilizing the initial torque can be obtained.

In addition to this, since each gear is composed of a helical gear, it is possible to adjust the differential limiting characteristics unevenly as in the structure of claim 6.

[Brief description of drawings]

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

FIG. 2 is an exploded perspective view showing constituent members of the first embodiment.

FIG. 3 is a sectional view showing a second embodiment of the present invention.

FIG. 4 is a sectional view taken along line AA of FIG. 3;

FIG. 5 is a cross-sectional view showing a disc spring and a washer used in the second embodiment.

FIG. 6 is a graph showing a differential limiting characteristic of the second embodiment.

FIG. 7 is a sectional view showing a third embodiment of the present invention.

FIG. 8 is a cross-sectional view showing a disc spring and a washer used in the third embodiment.

FIG. 9 is a sectional view of a conventional example.

FIG. 10 is an exploded perspective view showing constituent members of a conventional example.

[Explanation of symbols]

 1 Differential device 3, 91 Differential case 5, 93 Casing body 7, 9, 95 Cover 19, 21, 99, 101 Output side gear 41, 43, 119, 121 Storage hole 45, 47, 123, 125 Pinion gear 49, 57, 127, 133 First gear part 51, 53, 59, 61, 129, 135 Second gear part 55, 63, 131 Shaft part 67, 137, 159 Storage part for disc spring and sliding member 69, 139 Ring-shaped disc springs 71, 141 Washers (ring-shaped sliding members) 75 Supports 89, 157 Center differential (differential device) 143 Circumferential parts (supports)

Claims (7)

[Claims] 1. A diff case rotatably driven by a driving force of an engine, a pair of output side gears rotatably supported inside the diff case, and side gears arranged radially outside of these side gears. At least a pair of pinion gears having a first gear portion and a second gear portion that mesh with each other, a storage hole that is formed in a differential case and that slidably and rotatably accommodates each pinion gear, and one or both of each pair of pinion gears. A differential device comprising: a ring-shaped sliding member arranged to face the end surface; and an integral ring-shaped disc spring that presses the sliding member against the end surface to apply friction torque. 2. A differential case, a casing body and a cover.
2. The differential device according to claim 1, further comprising: a cover member provided with a sliding member and a disc spring accommodating portion. 3. The differential case has a casing body and a cover.
2. The differential device according to claim 1, further comprising: a casing body, and a housing for the sliding member and the disc spring. 4. The differential device according to claim 1, wherein one or both of the sliding member and the disc spring are supported on the inner circumference or the outer circumference by a support portion of a pinion gear provided on the differential case. 5. A pair of pinion gears have a shaft portion having a small diameter between the first and second gear portions to avoid interference with a side gear meshing with a mating pinion gear, and each second gear portion has a shaft of both side gears. The differential device according to any one of claims 1 to 4, comprising a pair of equal-length pinion gears meshing with each other on both sides in the direction, and disc springs arranged on the respective end face sides of both end faces of all the pinion gears to press them via sliding members. 6. A pair of pinion gears, a first pinion gear and a first pinion gear which have a small diameter shaft portion for avoiding interference between a short pinion gear having no shaft portion between the first and second gear portions and a side gear meshing with the short pinion gear. The differential device according to any one of claims 1 to 4, which comprises a long pinion gear provided between two gear portions, and a disc spring presses the end faces of all the pinion gears on the second gear portion side through a sliding member. 7. The gears are helical gears.
The differential device according to any one of 1 to 6.