JPH11201261A - Differential device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To intensify the differential limiting force by providing a friction clutch for differential limitation on the outside, maintaining the compatibility of each members at a high degree, realizing a low cost, and making the friction clutch large in diameter. SOLUTION: A differential device is provided with a differential case 17 housed in a casing 3, a differential mechanism 43 to distribute the rotation of the differential case 17 to the wheel side through side gears 39 and 41, a friction clutch 69 to limit the differential, an actuator 87 to fasten the friction clutch 69, a connecting member 53 on the side gear 39 side to penetrate the differential case 17 and the casing 3 to the outside, and a connecting member 71 connected to the differential case 17 through a connecting part 79, and the friction clutch 69 is arranged between the connecting members 53 and 71 on the outside of the casing 3.

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 or the like.

[0002]

2. Description of the Related Art A differential apparatus 201 as shown in FIG. 2 is described in Japanese Patent Laid-Open Publication No. Hei 4-366047.

[0003] This differential device 201 is a differential mechanism 2 for distributing the driving force of an engine for rotating a differential case 203 from output side gears 205 and 207 to wheels via drive shafts 209 and 211, respectively.
13, a pair of multi-plate clutches 217 and 217 respectively disposed between the hubs 215 and 215 connected to the side gears 205 and 207 and the inner periphery of the differential case 203,
It is composed of hydraulic actuators 223, 223 for pressing and fastening the multiple disc clutches 217, 217 via the pressing member 219 and the bearing 221.

[0004] The differential case 203 is housed in a differential carrier 225 and is supported at both ends via bearings 227.

When the multi-plate clutches 217, 217 are engaged, the frictional torques cause the side gears 205,
The differential of the differential mechanism 213 between the differential case 207 and the differential case 203 is limited, so that the running stability, maneuverability, and running on bad roads of the vehicle are improved.

[0006]

However, in the differential device 201, as described above, the multiple disc clutch 21
7 and 217 are arranged inside the differential case 203, so it is necessary to make the differential case 203 longer in the axial direction.
Compatibility with a normal differential housing without a built-in 17 has been lost.

Also, the axially long differential case 203 has a wider bearing span (the interval between the bearings 227 and 227), so that the differential carrier 225 also loses compatibility with a normal differential carrier.

In the differential device 201, a hydraulic actuator 223 disposed outside the differential case 203 presses the internal multi-plate clutch 217 so as to pass through the boss 229 of the differential case 203. The pressing member 219 is necessary, and the boss portion 229 has a larger diameter by penetrating the pressing member 219, thereby further reducing the compatibility of the differential case 203.

Further, since the bearing 227 supporting the large-diameter boss portion 229 needs to have such a large diameter,
The bearing 227 is also incompatible with the bearing used in a normal differential case, and the cost is accordingly increased.

In order to use the large-diameter bearing 227, the bearing housing 231 of the differential carrier 225 is required.
Needs a large diameter, and the bearing housing 23
If 1 has a large diameter, the compatibility of the carrier body 233 of the differential carrier 225 with a normal carrier body will be reduced.

As described above, the differential device 201 and the power transmission device shown in FIG. 2 in which the compatibility between the differential case 203 and the differential carrier 225 is lost can be formed at low cost by using a normal differential case or a differential carrier. I ca n’t,
It is costly.

Further, as described above, the differential carrier 225 having a wide bearing span and being long in the axial direction is disadvantageous in terms of strength. Therefore, for example, the weight is reduced by using a light alloy such as an aluminum alloy as a material. It is difficult.

Further, since each multi-plate clutch 217 accommodated in the differential case 203 is limited to the inner diameter of the differential case 203, the diameter cannot be increased.

Therefore, in order to increase the differential limiting force, the number of clutch plates must be increased. If the number of clutch plates is increased, the size of the differential case 203 and the differential carrier 225 increases in the axial direction, and the peripheral members become larger. There is a risk of interference.

Further, in a configuration in which the multi-plate clutch 217 is disposed inside the differential case 203 and the hydraulic actuator 223 is disposed outside, it is impossible to unitize these components, and the number of parts is reduced. However, various advantages due to unitization, such as being lightweight and compact, being easy to assemble and remove, and being low in cost, cannot be obtained.

Accordingly, the present invention provides a friction clutch for limiting the differential outside the differential case to maintain high compatibility of a large number of members including peripheral members, reduce the cost, and increase the size of the friction clutch. It is an object of the present invention to provide a differential device capable of increasing a diameter to enhance a differential limiting force.

[0017]

According to a first aspect of the present invention, there is provided a differential device comprising: a differential case rotatably accommodated in a casing; and a pair of output side gears for driving the engine input to the differential case. And a friction clutch for limiting the differential rotation of the differential mechanism between the side gear side and the differential case side, and an actuator for engaging the friction clutch. A differential device comprising: a side gear-side connecting member connected to a side gear and penetrating the differential case to the outside; and a differential case-side connecting member connected to the differential case via a connecting portion. The friction clutch is arranged between the connecting members outside the differential case.

The actuator engages a friction clutch,
Adjust the friction torque. With this friction torque,
The differential of the differential mechanism between the side gears and the differential case is limited, so that the running stability, maneuverability, and roadway failure of the vehicle are improved.

In the differential device according to the present invention, the connecting member on the side gear side is penetrated outside the differential case, the connecting member is provided on the differential case side, and a friction clutch is provided between these connecting members. The friction clutch was located outside the differential case.

As described above, since the differential case is shortened in the axial direction by disposing the friction clutch outside, unlike the conventional example in which the multi-plate clutch 217 is disposed inside the differential case 203, the friction clutch is Compatibility with a normal differential case without built-in is maintained.

The pressing member 2 penetrating through the boss 229 of the differential case 203 for pressing the multi-plate clutch 217
Unlike the prior art, which required 19, by disposing the friction clutch outside the differential case, it is possible to prevent the diameter of the boss portion from being increased by penetrating the member. Compatibility is maintained.

In this way, since the compatibility of the differential case is maintained, the differential device according to the present invention can be realized, for example, only by forming a connecting portion for connecting the differential case-side connecting member to the end of the boss portion. , A normal differential case can be used, and the configuration can be made at extremely low cost.

Also, unlike the conventional example, the friction clutch disposed outside the differential case is released from the restriction due to the inner diameter of the differential case. It became possible to strengthen.

Therefore, for example, when the friction clutch is configured as a multi-plate clutch, the differential limiting force can be enhanced without increasing the number of clutch plates, and the differential device can be enhanced while the differential limiting force is enhanced. The case for housing is prevented from being enlarged in the axial direction, and the effect of reducing the weight and the effect of preventing interference with peripheral members are improved.

Further, as described above, since the diameter of the boss portion of the differential case is prevented from being increased, it is not necessary to increase the diameter of the bearing that supports the boss portion, and this bearing maintains compatibility. It is possible to use a normal bearing for a differential case, and it is possible to realize a lower cost.

Further, by disposing the friction clutch outside the differential case, the friction clutch and the actuator can be unitized. By unitizing the friction clutch and the actuator, The number of parts is reduced, the weight and size are reduced, the assembling and removing operations are facilitated, and the cost is reduced.

According to a second aspect of the present invention, in the differential device according to the first aspect, the connecting member on the side gear side comprises:
A connection member penetrating further from the case to the outside of the casing, and a connecting member on the side of the case is disposed outside the case, and a friction clutch is provided outside the case to connect each connecting member. And an effect equivalent to that of the first aspect is obtained.

In addition, in this configuration, the connecting member on the side gear side is further penetrated from the differential case to the outside of the case, and the friction clutch is arranged outside the case.

Therefore, as described above, if a normal differential case with a narrow bearing span is used, it is not necessary to widen the bearing span of the case, and the case is compatible with the normal case. Sex is maintained.

Further, as described above, it is not necessary to increase the diameter of the bearing that supports the boss portion of the differential case. Therefore, it is necessary to increase the diameter of the bearing housing connected to the casing body of the casing. As a result, the compatibility between the bearing housing and the casing body is maintained.

Thus, by using the differential device of the present invention, the compatibility of the differential case is maintained and the case
Since the compatibility of the sing is maintained, the casing can be formed at a low cost by using a normal case.

Further, by disposing the friction clutch outside the casing, it is possible to further increase the diameter, and it is possible to greatly enhance the differential limiting force.

Therefore, for example, when the friction clutch is constituted by a multi-plate clutch, the differential limiting force can be enhanced without increasing the number of clutch plates, and the differential device can be enhanced while increasing the differential limiting force. The power transmission device including the motor and its casing is prevented from being enlarged in the axial direction, and the effect of reducing the weight and the effect of preventing interference with peripheral members are further improved.

As described above, the casing is advantageous in strength because the bearing span is narrow and short in the axial direction. Therefore, the weight is greatly reduced by using a light alloy material such as an aluminum alloy. It is possible to

According to a third aspect of the present invention, there is provided the differential device as set forth in the second aspect, wherein:
A sub-case containing the friction clutch is connected,
An actuator is attached to the sub-case to press the friction clutch, and the same effect as that of the second aspect is obtained.

In addition, a sub-case for accommodating the friction clutch is connected to the axial end of the casing, and the actuator is mounted on the sub-case, so that the friction clutch and the actuator are provided. Are unitized on this subcase.

As a result of the unitization, the friction clutch and the actuator are reduced in the number of parts, light and compact as compared with the case where they are individually constructed, and the assembling and removing operations are facilitated. , Lower cost.

In addition, since the sub-case for housing the friction clutch and the actuator is externally attached to the casing,
Since normal casing can be used as it is, the cost can be significantly reduced.

Further, since the diameter of the subcase externally attached to the casing can be increased, and the diameter of the friction clutch can be further increased, the differential limiting force is increased. Is extremely advantageous.

By providing this subcase,
Since a cover member at the end portion, such as a bearing housing, connected to the casing body is not required, the number of parts does not increase even if the subcase is provided.

According to a fourth aspect of the present invention, there is provided the differential device according to the third aspect, wherein the actuator is a sub-casing.
And a piston which is movably engaged with the cylinder, receives the operating pressure from the cylinder, and presses the friction clutch via the piston. Get the effect.

In addition, by forming the cylinder of the actuator in a subcase, the friction clutch and the actuator are unitized on the subcase, as in the construction of the third aspect. As described above, the unitization of the friction clutch and the actuator reduces the number of parts, makes them lightweight and compact, facilitates the assembling work and the removing work, and reduces the cost.

Also, an actuator which operates by receiving a fluid pressure
Since a large pressing force and a differential limiting force can be obtained, the friction clutch can be reduced in size accordingly, which is advantageous for reducing the size and weight of the differential device, and preventing interference with peripheral members. Is improved.

The invention according to claim 5 is the invention according to claims 1 to 4.
A clutch for accommodating a friction clutch is provided, and a seal for preventing oil leakage between a differential case and a partition formed in a casing and a connecting member on a side gear side is provided. Are arranged, and the same effects as those of the first to fourth aspects are obtained.

In addition, a seal for preventing oil leakage is arranged between the differential case and the partition formed on the casing and the connecting member on the side gear side, so that the clutch chamber and the casing are different from each other. It became possible to fill oil.

In this way, it is possible to lubricate the friction clutch and the differential mechanism with optimal oil, respectively, so that their performance is stabilized and the durability is greatly improved.

The invention of claim 6 is the invention of claims 1 to 4
Wherein the clutch chamber for accommodating the friction clutch is provided, and the connecting member on the side gear side is provided with an oil passage communicating the clutch chamber and the casing. In this case, the same effects as those of the first to fourth aspects are obtained.

In addition to this, the connection member on the side gear side is provided with an oil flow path for communicating the clutch chamber with the casing, so that the oil sent from the casing to the clutch chamber via this oil flow path is provided. This lubricates the friction clutch, stabilizes performance and greatly improves durability.

Further, since the oil is supplied from the casing as described above, the clutch chamber does not need to be provided with an oil supply means such as an oil sump, so that the cost can be reduced accordingly.

The invention of claim 7 is the first to sixth aspects of the present invention.
The differential device according to any one of the above, wherein the connecting member on the differential case side is a clutch drum having a connecting portion to the differential case and a large-diameter drum portion, and the connecting member on the side gear side is And an output shaft connected to the side gear and a clutch hub connected to an outer periphery of the output shaft, wherein a friction clutch is disposed between the drum portion and the clutch hub. An effect equivalent to that of the configuration of claim 6 is obtained.

In addition to this, it is easy to increase the diameter of the friction clutch disposed between the large-diameter drum portion and the clutch hub. Is obtained, and the differential limiting force can be configured to be thinner than a friction clutch having the same differential force.
This is advantageous in reducing the size and weight of the differential device,
The effect of preventing interference with peripheral members is improved.

[0052]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIG. This embodiment is defined in claims 1, 2, 3, 4,
6 and 7 are provided. FIG. 1 shows a differential device 1 of this embodiment, and the left and right directions are the vehicle in which the differential device 1 is used and the left and right directions in FIG. In addition, members and the like without reference numerals are not shown.

The differential device 1 is a differential carrier 3
(Casing).

The differential carrier 3 comprises a differential carrier body 5
And a cover 9 fixed to the right end of the differential carrier body 5 with bolts 7, a bearing housing 11 screwed to the cover 9, and the like. An oil reservoir is provided on the differential carrier 3, and an O-ring 12 for preventing oil leakage is arranged between the cover 9 and the bearing housing 11.

Also, on the left end of the differential carrier body 5,
The sub-case 13 is fixed by bolts 15.

The differential case 17 of the differential device 1
The left boss 19 is supported by the differential carrier body 5 by a bearing 21, and the right boss 23 is supported by the bearing housing 9 by a bearing 25.

A ring gear 27 is fixed to the differential case 17 by bolts 28, and the ring gear 27 meshes with a drive pinion gear 29. The drive pinion gear 29 is formed integrally with the rear end of the drive pinion shaft, and the drive pinion shaft is connected to the propeller shaft via a joint.

Thus, the differential case 17 is driven to rotate by the driving force of the engine transmitted from the transmission via the propeller shaft.

A plurality of pinion shafts 31 are radially arranged inside the differential case 17, and each of the pinion shafts 31 is engaged with a through hole 33 of the differential case 17 and is prevented from rotating by a spring pin 35. Have been.
A pinion gear 37 is rotatably supported on each pinion shaft 31, and left and right side gears 39 and 41 mesh with each pinion gear 37 to form a bevel gear type differential gear mechanism 43 (differential mechanism). I have.

The pinion gear 3 is provided on the inner periphery of the differential case 17.
7, a spherical washer 45 receiving a meshing reaction force. The side gears 39 and 41 are connected to the differential case 17.
Are rotatably supported by the support portions 47 and 49, and are supported from the radial outside by meshing with the pinion gear 37. Thrust washers 51, 51, which receive a reaction force of the engagement between the side gears 39, 41, are arranged between the side gears 39, 41 and the differential case 17 to reduce sliding resistance.

The side gears 39 and 41 are spline-connected to left and right drive shafts 53 and 55 (output shafts), respectively, and are fixed by retaining rings 57, respectively. The left drive shaft 53 penetrates the boss 19 of the differential case 17, the differential carrier 3 and the sub case 13 to the outside, and is connected to the left wheel via a joint 59 and another drive shaft. The drive shaft 53 has its left end supported on the sub-case 13 by a bearing 61.

The right drive shaft 55 is a differential case 1
7 and the bearing housing 9 penetrate to the outside, and are connected to the right wheel via a joint 63 and another drive shaft.

A seal 65 is arranged between the drive shaft 53 and the sub-case 13, and a drive shaft 55
A seal 67 is disposed between the bearing and the bearing housing 9 to prevent oil from leaking to the outside.

The driving force of the engine for rotating the differential case 17 is distributed from the pinion shaft 31 to the side gears 39 and 41 via the pinion gear 37 and transmitted to the left and right wheels. When a difference in driving resistance occurs between wheels on a bad road or the like, the driving force of the engine is differentially distributed to the left and right sides by the rotation of the pinion gear 37.

A clutch chamber 68 is formed between the sub-case 13 and the differential carrier main body 5, and a multi-plate clutch 69 (friction clutch) is disposed inside the clutch chamber 68.

The multi-plate clutch 69 is a clutch drum 7
An outer plate 74 (clutch plate) axially movably engaged with the inner periphery of a large-diameter drum portion 73 formed on the outer periphery of a clutch hub 75. It is composed of an inner plate 77 (clutch plate) engaged axially movably.

The clutch drum 71 is connected to the boss 19 of the differential case 17 via a connecting portion 79, and the clutch hub 75 is a lug groove formed on the outer periphery of the drive shaft 53 (the connecting member on the side gear 39 side). 81 (engagement groove:
Oil passage). The lug groove 81 penetrates through the differential carrier 3 and the differential case 17 from the clutch chamber 68 and communicates them.

A needle bearing 82 is disposed between the clutch drum 71 and the clutch hub 75 which rotate relatively to reduce the rotational resistance.

A cylinder 83 is formed in the sub-case 13, and a piston 85 is movably engaged with the cylinder 83 via a seal to constitute a hydraulic actuator 87.

An oil pressure is sent to the cylinder 83 from an engine-driven oil pump via a control valve and an oil pipe 89. The control valve is opened and closed by a controller according to a change in a road surface condition, a steering condition, or the like, or its opening degree is adjusted, and the hydraulic pressure supplied to the cylinder 83 is adjusted.

A return spring 91 is disposed between the piston 85 and the clutch hub 75.

When the hydraulic pressure is supplied to the cylinder 83, the hydraulic actuator 87 presses and engages the multi-plate clutch 69 with the piston 85, and the side gear 39 and the differential case 17 are moved by the differential limiting force (friction torque). , The differential of the differential gear mechanism 43 is limited. Further, as described above, the differential limiting force is adjusted according to the road surface condition and the steering condition by adjusting the hydraulic pressure of the control valve, and greatly improves the running stability, maneuverability, and bad road running failure of the vehicle. .

When the supply of the hydraulic pressure is stopped, the piston 8
5 is retracted by the return spring 91, and the engagement of the multi-plate clutch 69 is released.

Openings 93 and 93 are provided in the differential case 17. When the differential case 17 rotates, the oil repelled from the oil reservoir of the differential carrier 3 by the ring gear 27 passes through these openings 93 to the differential case. 17 and lubricates and cools each gear and sliding portion of the differential gear mechanism 43 to prevent seizure and abnormal wear and improve durability.

Further, the oil is supplied to the drive shaft 53
Through the lug groove 81 of the multi-plate clutch 69 to lubricate and cool the sliding surface between the outer plate 74 and the inner plate 77 to reduce seizure and abnormal wear. Prevent and improve durability.

Thus, the differential device 1 is configured.

As described above, in the differential device 1, the clutch drum 71 is disposed outside the differential case 17 and the differential carrier 3, and the multi-plate clutch 69 is provided between the drive shaft 53 and the clutch drum 71. The multi-plate clutch 69 is arranged outside the differential case 17 and the differential carrier 3.

As described above, since the differential case 17 without the built-in multi-plate clutch 69 is shortened in the axial direction, compatibility with a normal differential case without a built-in friction clutch is maintained unlike the conventional example. It is.

Further, by disposing the multi-plate clutch 69 outside the differential case 17, the diameter of the boss portion 19 and the bearing 21 for supporting the boss portion 19 can be increased by penetrating the member, unlike the conventional example. Are prevented, the compatibility of the differential case 17 is maintained for this reason as well.

Therefore, the boss 19 is provided on the differential case 17.
Connecting portion 79 for connecting the clutch drum 71 to the end of
An ordinary differential case is used.

Thus, the differential device 1 using the ordinary differential case is configured at a lower cost.

Further, by using a normal differential case having a narrow bearing span for the differential case 17, there is no need to increase the bearing span of the differential carrier 3, so that the differential carrier 3 is also compatible with the normal differential carrier. Dripping.

Further, as described above, the diameter of the bearing 21 of the boss 19 does not need to be large, and the diameter of the cover 9 and the bearing housing 11 connected to the differential carrier main body 5 does not need to be large. Body 5 and cover 9
Carrier 3 consisting of a bearing housing 11
Is compatible for this reason.

Further, the sub-case 13 accommodating the multi-plate clutch 69 and the hydraulic actuator 87 is mounted on the differential carrier 3.
Since the external carrier can be used for the differential carrier 3 as it is,
The compatibility of the differential carrier 3 is kept higher.

As described above, since the differential device 1 is accommodated, the differential carrier 3 is also configured at low cost by using a normal differential carrier.

Unlike the conventional example, the multi-plate clutch 69 disposed outside the differential case 17 and the differential carrier 3 is different from the conventional example.
Is released from the limitation by the inner diameter of the differential case 17 and the differential carrier 3, so that the outer plate 74 and the inner
The plate 77 can be made as large as necessary to enhance the differential limiting force.

Therefore, the outer plate 74 and the inner plate 74
It is possible to enhance the differential limiting force without increasing the number of plates 77, and by increasing the number of plates 77, it is possible to prevent the sub-case 13 from being enlarged in the axial direction and to interfere with peripheral members. The prevention effect improves accordingly.

Further, as described above, the bearing 21 for supporting the boss portion 19 does not need to be made large in diameter, and the compatibility is maintained. Therefore, it is possible to use a normal bearing for a differential case. , It has become lower cost.

The multi-plate clutch 69 is accommodated in the sub-case 13 connected to the differential carrier 3 and the cylinder 83 of the hydraulic actuator 87 is formed in the sub-case 13, so that the multi-plate clutch 69 and the hydraulic actuator are formed. The unit 87 is formed on the subcase 13 as a unit.

This unitization allows the multiple disc clutch 6
9 and the hydraulic actuator 87 have a reduced number of parts, are lighter and more compact, are easier to assemble and remove, and are lower in cost as compared to the case where they are individually constructed. I have.

Further, since the diameter of the sub-case 13 can be increased by externally attaching it to the differential carrier 3, the diameter of the multi-plate clutch 69 can be further increased and the differential limiting force can be increased. It is very advantageous.

Further, since the sub-case 13 is externally attached, a cover member on the left end side connected to the differential carrier body 5 of the differential carrier 3 becomes unnecessary.
However, the number of parts does not increase even if the number is provided.

The hydraulic actuator 87 can provide a large pressing force and a differential limiting force.
Is so small.

Since the multi-plate clutch 69 is thin,
The sub-case 13 (differential device 1) is shortened in the axial direction accordingly.

Further, the multi-plate clutch 69 can adjust the differential limiting force by changing the number of the outer plate 74 and the inner plate 77 without largely changing the axial dimension.

The maintenance and repair of the multi-plate clutch 69 can be performed relatively easily by exchanging the outer plate 74 and the inner plate 77.

The multi-plate clutch 69 disposed between the large-diameter clutch drum 71 and the clutch hub 75 has such a large diameter that a large differential limiting force can be obtained and the differential limiting force is the same. The sub-case 13 (differential device 1) can be made thinner than a friction clutch.
This is advantageous for miniaturization.

Further, the multi-plate clutch 69 and the hydraulic actuator
Since the gear 87 is arranged only on one side gear 39 side and the differential device 1 and the differential carrier 3 are configured to be shorter in the axial direction, they are arranged around a joint or an axle such as an arm or spring for suspension. This is extremely advantageous in preventing interference with the member to be formed.

The bevel gear type differential gear mechanism 43 is
Since the differential device 1 is configured to be shorter in the axial direction than the other types of differential mechanisms, the differential device 1 can be shortened in the axial direction by that much, and the compatibility between the differential device 17 and the differential carrier 3 as described above is maintained. Is advantageous.

Further, since the multi-plate clutch 69 is lubricated by the oil sent from the differential carrier 3 to the clutch chamber 68 via the lug groove 81 of the drive shaft 53, the performance is stabilized and the durability is greatly improved.

Since oil is supplied from the differential carrier 3 in this manner, the clutch chamber 68 does not need to be provided with an oil supply means such as an oil sump, so that the cost can be reduced accordingly.

An existing lug groove 81 provided on the drive shaft 53 for connecting the clutch hub 75 is provided.
Since the oil passage is used for the oil passage, there is no need to newly process the oil passage, and the cost can be further reduced.

In the differential device of the present invention, a seal for preventing oil leakage between the differential case and the partition formed on the casing and the connecting member on the side gear side.
With this arrangement, it is possible to fill the clutch chamber and the casing with different oils, lubricate the friction clutch and the differential mechanism with optimal oil, stabilize the performance of each, and improve durability. Can be greatly improved (the configuration of claim 5).

Further, if this seal is arranged between the clutch drum and the partition, there is no need to separately prepare a member or a space for arranging the seal, so that it can be implemented at a low cost. become.

In the differential device of the present invention,
As described above, since the diameter of the friction clutch can be increased, the clutch device used for the automatic transmission can be used as needed.

As described above, if the clutch device for an automatic transmission is diverted, a large differential limiting force can be obtained due to its large torque capacity, and the cost is greatly reduced due to the diversion effect.

In the differential device of the present invention,
Since a normal casing with a narrow bearing span and high strength can be used, it is possible to use an aluminum alloy for the material of the casing, and to use an aluminum alloy for the casing. As a result, the power transmission device including the differential device and the casing can be significantly reduced in weight.

In the differential device of the present invention,
An actuator that uses pressure or electromagnetic force as a drive source can be used as the actuator (claim 14).

The actuator using pressure as the driving source can provide a large pressing force and a differential limiting force as in the above-described embodiment, and can reduce the size of the friction clutch accordingly. This is advantageous for miniaturization.

An actuator using an electromagnetic force as a drive source includes, for example, an electric motor for extracting a rotational force and a thrust force by a rotating magnetic field and a moving magnetic field moving linearly.
Actuators including a cam mechanism for converting the driving force into a pressing force of a friction clutch, and an electromagnetic actuator for pressing the friction clutch by a magnetic attraction force.

In each case, a sufficient pressing force (differential limiting force) can be obtained, and the power can be adjusted to control the differential limiting force quickly and easily. The differential limiting force can be precisely controlled according to changes in the state, steering conditions, and the like, so that the traveling performance and stability of the vehicle can be greatly improved.

Since the vehicle has a power source such as a battery and an alternator driven by an engine, such an actuator using electromagnetic force as a driving source is extremely easy to use.

In general, since the time for limiting the differential in the running time is short, such an actuator obtains a sufficient differential limiting force, consumes less power, and has a burden on the power supply and the fuel consumption of the engine. Is small.

The actuator using electromagnetic force as a driving source is compact and does not require the routing of a pressure pipe. Therefore, it is easy to unitize the clutch device which is one of the features of the present invention. is there.

In the differential device of the present invention,
Different from the above embodiment, the friction clutch and the actuator may be arranged on both side gears.

Further, in the differential device of the present invention, the differential mechanism is not limited to the bevel gear type.

For example, a planetary gear type differential gear mechanism, a worm gear type differential gear mechanism, a differential gear mechanism in which side gears are connected by a pinion gear disposed in a housing hole of a differential case, or the like may be used. Alternatively, a differential mechanism that does not use gears may be used.

Further, the friction clutch may be a friction clutch other than the clutch plate type, for example, a cone clutch.

The actuator is not a hydraulically operated type, but may be, for example, an actuator operated by another fluid pressure such as a pneumatic type.

The differential device of the present invention includes a front differential (a differential device for distributing the driving force of the engine to the left and right front wheels) and a rear differential (a differential device for distributing the driving force of the engine to the right and left rear wheels) and a center differential. It can be used for any of differentials (differential devices that distribute the driving force of the engine to front wheels and rear wheels).

[0121]

According to a first aspect of the present invention, there is provided a differential device comprising: a side gear side connecting member protruding outside a differential case;
By providing a friction clutch between the differential case side connecting member and the friction clutch, the friction clutch is arranged outside the differential case. Unlike the conventional example, the differential case is shortened in the axial direction, and the friction clutch is built in. No compatibility with the normal differential case is maintained.

Further, since the diameter of the boss portion is prevented from being increased by penetrating the member, the compatibility of the differential case is maintained for this reason.

Thus, the differential device of the present invention can be constructed at low cost by using a normal differential case.

Further, since the friction clutch is released from the limitation due to the inner diameter of the differential case, it is possible to increase the diameter as much as necessary to enhance the differential limiting force.

Therefore, in the case of a multi-plate clutch, the differential limiting force can be strengthened without increasing the number of clutch plates, and the casing for accommodating the differential device is strengthened while increasing the differential limiting force. Thing is prevented from becoming large in the axial direction, and the effect of preventing interference with peripheral members is improved.

Further, since the diameter of the boss portion of the differential case is prevented from being increased, it is not necessary to increase the diameter of the bearing for supporting the boss portion, so that a normal differential case bearing can be used. , It can be configured at a lower cost.

Further, by disposing the friction clutch outside the differential case, it is possible to unitize the friction clutch and the actuator. Each operation of assembling and removing becomes easy, and the cost is reduced.

According to the second aspect of the present invention, the same effect as that of the first aspect is obtained, and the connecting member on the side gear side is further penetrated from the differential case to the outside of the case, thereby connecting the friction clutch to the case. Because it is located outside, normal defuke
The use of the casing eliminates the need for the casing to have a wide bearing span, thereby maintaining compatibility with ordinary casing.

Further, the bearing of the differential case does not have a large diameter and the bearing housing of the casing does not need to have a large diameter, so that the compatibility of the casing is further enhanced.

In this way, by using the differential device of the present invention, the compatibility of the casing is maintained, so that the casing can be formed at low cost by using a normal case.

Further, by disposing the friction clutch outside the casing, it is possible to further increase the diameter and to greatly enhance the differential limiting force.

Therefore, in the case of a multi-plate clutch, the differential limiting force can be strengthened without increasing the number of clutch plates by making the diameter sufficiently large, so that the differential device and its casing are used. And the effect of preventing interference between the power transmission device and the peripheral members is further improved.

In addition, since the casing is advantageous in terms of strength because the bearing span is narrow and short in the axial direction, it is possible to greatly reduce the weight by using a light alloy material such as an aluminum alloy. .

According to the third aspect of the invention, the same effect as that of the second aspect is obtained, and a sub-case is connected to the axial end of the casing, so that the friction clutch and the actuator are connected to the sub-case. As a result, the number of parts is reduced, the weight and compactness are reduced, the assembly and removal are easy, and the cost is reduced as compared with the case where each is individually configured.

Further, since the sub-case is externally attached to the case, it is possible to use the normal case as it is, which is advantageous for a low-cost construction.

Further, since the diameter of the sub-case externally attached to the casing can be increased, and the diameter of the friction clutch can be further increased, it is extremely advantageous for strengthening the differential limiting force. is there.

Further, even if the sub-case is provided, the number of parts does not increase because a cover member at the end connected to the casing body is not required.

According to a fourth aspect of the present invention, the actuator cylinder is formed in a subcase, and the friction clutch and the actuator are unitized on the subcase. The number of parts is reduced, the weight and size are reduced, the assembling work and the removing work are facilitated, and the cost is reduced.

Actuators that operate by receiving fluid pressure
Since a large pressing force and a differential limiting force can be obtained, the friction clutch can be reduced in size accordingly, which is advantageous for reducing the size of the differential device.

The invention of claim 5 is the invention of claims 1 to 4.
The same effect as in the above configuration is obtained, and a seal for preventing oil leakage is arranged between the differential case and the partition member formed on the casing and the connecting member on the side gear side, thereby preventing oil leakage. The casing and the casing are filled with different oils, and the friction clutch and the differential mechanism can be lubricated with the optimal oil, so that their performance is stabilized and the durability is greatly improved.

The invention of claim 6 is the invention of claims 1 to 4
And the friction clutch is lubricated by oil sent from the casing side to the clutch chamber through an oil passage provided in the connecting member on the side gear side, so that the performance is stabilized and the durability is improved. Greatly improved.

Further, it is not necessary to provide an oil supply means such as an oil reservoir in the clutch chamber, and the cost can be reduced accordingly.

The invention of claim 7 is the first to sixth aspects of the present invention.
And the friction clutch is arranged between the large-diameter drum portion and the clutch hub, so that the diameter can be easily increased, and the large diameter can provide a large differential limiting force. Also, since the friction limiting clutch can be configured to be thinner than a friction clutch having the same differential limiting force, it is advantageous for downsizing the differential device.

[Brief description of the drawings]

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

FIG. 2 is a sectional view of a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Differential device 3 Differential carrier (casing) 13 Subcase 17 Differential case 31 Pinion shaft 37 Pinion gear 39, 41 Output side gear 43 Bevel gear type differential gear mechanism 53 Drive shaft (output shaft: connecting member on the side of the side gear 39) ) 68 Clutch chamber 69 Multi-plate clutch (friction clutch) 71 Clutch drum (Connecting member on differential case side) 73 Large-diameter drum part 74 Outer plate (clutch plate) 75 Clutch hub 77 Inner plate ( Clutch plate) 79 Coupling part of clutch drum 81 Lug groove (engagement groove: oil flow path) with which clutch hub engages 83 Cylinder 85 Piston 87 Hydraulic actuator (actuator)

Claims (7)

[Claims] A differential mechanism rotatably accommodated in a casing, and a differential mechanism for distributing a driving force of an engine input to the differential case to a wheel through a pair of output side gears. A differential device comprising a friction clutch for limiting the differential rotation of the differential mechanism between the side gear side and the differential case side, and an actuator for engaging the friction clutch, the differential device being connected to the side gear. A connecting member on the side gear side penetrating the differential case to the outside, and a connecting member on the differential case connected to the differential case via a connecting portion, wherein the friction clutch is provided outside the differential case. A differential device, which is arranged between each connecting member. 2. The invention according to claim 1, wherein the connecting member on the side gear side further penetrates outside the casing from the differential case, and the connecting member on the differential case side includes:
The friction clutch, which is arranged outside the casing,
A differential device, which is arranged between the connecting members outside the casing. 3. A sub-case for accommodating a friction clutch is connected to an axial end of the case, and an actuator is attached to the sub-case. And a friction clutch is pressed. 4. The invention according to claim 3, wherein the actuator comprises a cylinder formed in a subcase and a piston movably engaged with the cylinder, and the cylinder receives operating pressure. A differential clutch for pressing a friction clutch via a piston. 5. The invention according to claim 1, wherein a clutch chamber for accommodating a friction clutch is provided, a partition formed in a differential case and a casing, and a connecting member on a side gear side. A seal for preventing oil leakage is disposed between the differential device and the seal device. 6. The invention according to claim 1, wherein a clutch chamber for accommodating the friction clutch is provided, and the coupling member on the side gear side is provided with the clutch chamber and the casing. A differential oil passage communicating with the oil passage. 7. The invention according to claim 1, wherein the connecting member on the differential case side has a connecting portion with the differential case and a large-diameter drum portion. A clutch drum, wherein a connection member on the side gear side includes an output shaft connected to the side gear and a clutch hub connected to an outer periphery of the output shaft, and a friction clutch is disposed between the drum portion and the clutch hub. A differential device.