JPH09267657A - Free wheel clutch for four-wheel-drive vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent generation of gear noise by providing a key moved to an inner differential case side by axial direction moving of a sleeve, and providing a multidisk clutch pressed through an inner differential case by this moving of the key between inner/outer differential cases. SOLUTION: When a drive is switched from two-wheel drive to four-wheel drive and in the case of full time four-wheel drive, when a free axle switching sleeve 56 is moved in an axial direction to a side of an inner differential case 26, a key 64 is moved in an axial direction to a side of the inner differential case 26, a side surface of a free axle lock part 48 is pressed. When a sleeve line 52 is engaged with a hub spline 50, a multidisk clutch 72 is pressed through the inner differential case 26, so as to synchronize rotation of the inner differential case 26 and first/second outer differential cases 28, 30 by a synchro function. Here, a recessed part 54 of the free axle switching sleeve 56 and a protruded part 66 of the key 64 are fitted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a freewheel clutch for a four-wheel drive vehicle, and more particularly to a freewheel clutch for a four-wheel drive vehicle that can prevent gear squeal.

[0002]

2. Description of the Related Art In a four-wheel drive vehicle, in order to enable smooth driving automatically without slipping when the left and right driving wheels need to have a rotational difference due to turning motion during traveling. Is equipped with a differential device.

FIG. 7 shows a differential device.
As shown in, some of them are provided with a freewheel clutch. That is, in the differential device 102, the hypoid gear 104 that meshes with the drive pinion (not shown) of the drive shaft is attached to the differential case 108 by the fixing bolt 106. The differential case 108 includes an inner differential case 110, a first outer differential case 112, and a second outer differential case 114.

A differential pinion shaft 116 is held in the inner differential case 110, and the differential pinion shaft 11 is held.
First and second differential pinions 118-1 and 1, which are pivotally supported by 6
18-2 is built in. Left and right first and second differential side gears 120-1 and 120-2 are meshed with the first and second differential pinions 118-1 and 118-2.

The hypoid gear 104 is actually fixed to the first outer differential case 112 and the second outer differential case 112 by the fixing bolt 106.
It is fixed to the outer differential case 114.

The first outer differential case 228 is rotatably provided relative to the inner differential case 110. Therefore, the differential case 108 is the inner differential case 1.
10 and the first outer differential case 112 are doubled, and the first outer differential case 112 is held by the second outer differential case 114.

Further, the first outer differential case 112 has a first
Case boss 122-1 and second outer differential case 114
The second case boss 122-2 of the first and second bearings 1
It is supported by a differential carrier (not shown) by 24-1 and 124-2.

First and second differential side gears 120-1 and 1
The end portions of the first and second axle shafts (not shown) are connected to 20-2. The first and second axle shafts are
It is supported by the first and second case boss portions 122-1 and 122-2.

In this differential device 102,
In a four-wheel drive vehicle, a freewheel clutch 126 is provided to reduce resistance for rotating a non-drive shaft during two-wheel drive (2WD).

The free wheel clutch 126 is a free sleeve which is moved in the axial direction of the first axle shaft so as to engage / disengage the free axle lock portion 128 provided on the inner differential case 110 and the first outer differential case 112. It has an axle switching sleeve 130.
The free axle switching sleeve 130 is supported by the first outer differential case 112.

This free axle switching sleeve 130
One end side of the free axle switching fork 132 is engaged with. Switching fork 1 for this free axle
Although not shown, the other end side of 32 is connected to an actuator via a shifter shaft. In this actuator, the switching fork 132 for the shifter shaft and the free axle is used.
The free axle switching sleeve 130 is moved in the axial direction via the shaft, and the sleeve spline 134 and the free axle lock portion 128 of the free axle switching sleeve 130 are moved.
The hub spline 136 is engaged / disengaged.

That is, in the free wheel clutch 126, when the two wheels are driven (2WD), the first and second axle shafts and the first and second differential side gears 120-1 and 120-.
2 and 1st, 2nd differential pinion 118-1, 118-
Although the 2 and the inner differential case 110 are rotated by the rotation of the tire, the first and second outer differential cases 112,
Since the driving force is not transmitted, the 114 and the hypoid gear 104 do not rotate. Further, during four-wheel drive (4WD), the free-axle switching sleeve 130 is axially moved and coupled to the arele-axle lock portion 128.
The driving force is transmitted to the first and second axle shafts.

Further, as a clutch for such a vehicle, for example, Japanese Utility Model Publication No. 63-8490, Japanese Patent Laid-Open No.
It is disclosed in Japanese Patent No. 38734. Mitsuko Sho 63-84
The device disclosed in Japanese Patent Publication No. 90 is transmitted to the rear wheels by connecting the two-wheel and four-wheel clutches and then connecting the drive system stationary clutch with a delay of a predetermined time by the integrating circuit to drive the four wheels. The rotation of the shafts is made substantially equal by the power by the differential device, and the engagement of the drive system stationary clutch is smoothly performed. The one disclosed in Japanese Patent Laid-Open No. 2-38734 has a multi-plate clutch, makes a differential case of a differential gear mechanism movable, and connects and switches the differential case and the second rotating member by the movement of the differential case. By arranging the clutch and the second clutch for connecting / switching the differential case and the electric member on the inner peripheral side of the electric member, the optimum driving state according to the road surface condition or the traveling condition can be obtained by operating the operation member. The control system for obtaining the optimum drive state is simplified, and as a result, the cost of the power transmission device as a whole is reduced and the risk of failure is eliminated.

[0014]

However, in the conventional freewheel clutch, since the simple axle lock and the free axle are switched by the spline connection, when shifting to four-wheel drive (4WD), If the rotation speed of the propulsion shaft and the rotation speed of the tires are not perfectly synchronized at the time of sudden acceleration, stacking, etc., there is the inconvenience that a gear squeal occurs between the free axle switching sleeve and the inner differential case. there were.

[0015]

Therefore, in order to eliminate the above-mentioned inconvenience, the present invention provides an inner differential case which holds a differential pinion shaft and has the differential pinion shaft and the differential pinion built therein. In a free wheel clutch of a four-wheel drive vehicle, a rotatable outer differential case is provided, and a sleeve is axially moved so as to connect the inner differential case and the outer differential case when driving four wheels. A key that is moved to the inner differential case side is provided, and a multi-plate clutch that is pressed by the movement of the key via the inner differential case is provided between the inner differential case and the outer differential case.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION According to the present invention, when the axle is locked, the key is axially moved by the axial movement of the sleeve, and this key presses the multi-plate clutch via the hub. Can be prevented, and the effect similar to that of the viscous force coupling can be provided by the multi-plate clutch, and the effect of the viscous coupling can be changed by adjusting the pressing force of the multi-plate clutch. be able to.

[0017]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention; 1 to 6 show an embodiment of the present invention. In FIG. 1, 2 is a differential device and 4 is a differential carrier. A drive shaft 8 is axially supported in the differential carrier 4 by front and rear tapered roller bearings 6-1 and 6-2 held by the differential carrier 4. A propulsion shaft connecting flange 10 for connecting a propulsion shaft (not shown) is attached to the drive shaft 8 by a flange mounting nut 12 at one end side, and a drive pinion 14 is continuously provided at the other end side. .
The front tapered roller bearing 6-1 and the rear tapered roller bearing 6-
A spacer 16 is provided between the two.

A differential cover 18 is attached to the differential carrier 4.

A hypoid gear 20 is meshed with the drive pinion 14 of the drive shaft 8. The hypoid gear 20 is fixed to the differential case 24 by a fixing bolt 22.
Mounted on The differential case 24 includes an inner differential case 26, a first outer differential case 28, and a second outer differential case 30.

The inner differential case 26 holds a diff pinion shaft 32, and also incorporates first and second diff pinions 34-1 and 34-2 pivotally supported by the diff pinion shaft 32. The first and second differential pinion 34-
1, 34-2 includes left and right first and second differential side gears 3
6-1 and 36-2 are meshed with each other.

The hypoid gear 20 is actually attached to the first outer differential case 28 and the second outer differential case 30 by the fixing bolts 22.

The first outer differential case 28 is rotatably provided relative to the inner differential case 26.
Therefore, in the differential case 24, the inner differential case 26 and the first outer differential case 28 are doubled, and
The outer differential case 28 is configured to be held by the second outer differential case 30.

Further, the first case boss portion 38-1 of the first outer differential case 28 and the second case of the second outer differential case 30.
The case boss portion 38-2 is supported by the differential carrier 4 by the first and second bearings 42-1 and 42-2 held by the left and right first and second carrier boss portions 40-1 and 40-2. ing.

First and second differential side gears 36-1, 36
-2 is connected to the end portions of the first and second axle shafts 44-1 and 44-2. The first and second axle shafts 4
4-1 and 44-2 are the first and second case bosses 38-.
It is supported by 1, 38-2.

The differential device 2 is provided with a freewheel clutch 46.

The free wheel clutch 46, as shown in FIGS. 1 and 2, has a hub spline 50 formed on a free axle lock portion 48 provided on the inner differential case 26.
And a free axle switching sleeve 56 that is a sleeve that is formed with a sleeve spline 52 and a recess 54 to engage with and disengage from the hub spline 50 and that is moved in the axial direction of the first axle shaft 44-1. ing. The free axle switching sleeve 56 is supported by the first outer differential case 28.

One end side of a free axle switching fork 58 is engaged with the free axle switching sleeve 56. The other end side of the free fork switching fork 58 is connected to an actuator 62 via a shifter shaft 60 arranged substantially parallel to the first axle shaft 44-1.

The free axle switching sleeve 56 includes:
A key 64 is provided in engagement. The key 64 is moved to the inner differential case 26 side by axially moving the free axle switching sleeve 56.

The key 64 is formed with a convex portion 66 that engages with the sleeve spline 50 of the free axle switching sleeve 56 and that is fitted into and disengaged from the concave portion 54 of the free axle switching sleeve 56. .

The key 64 is pressed toward the free axle switching sleeve 56 by springs 68-1 and 68-2 provided at both ends of the inner surface.

Further, the end surface of the key 64 opposite to the hub 26 is locked to the ring pin 70 attached to the first case boss portion 38-1.

A multi-disc clutch 72 is pressed between the inner differential case 26 and the first outer differential case 28 via the inner differential case 26 by the axial movement of the key 64.
Is provided. The multi-disc clutch 72 has the same structure as the conventional one, and is held by the inner differential case 26 and the first and second outer differential cases 28, 30.

Next, the operation of this embodiment will be described.

When the vehicle is driven by two wheels (2WD) and the axle is free, the free axle switching sleeve 56 is separated from the hub spline 50 as shown in FIG.
Is separated from the inner differential case 26 side.

When switching from two-wheel drive (2WD) to four-wheel drive (4WD) and full-time four-wheel drive (4W)
In the case of D), as shown in FIG. 5, when the free axle switching sleeve 56 is axially moved to the inner differential case 26 side, the key 64 is axially moved to the inner differential case 26 side and the free axle lock portion is obtained. Press the side of 48. When the sleeve spline 52 is engaged with the hub spline 50, the multi-plate clutch 72 is pressed via the inner differential case 26, so that the inner differential case 26 and the first and second outer differential cases 28, 30 are synchronized by the synchronizing function. The rotation can be synchronized.
At this time, the concave portion 5 of the free axle switching sleeve 56
4 and the convex portion 66 of the key 64 are fitted together.

Then, the switching sleeve 5 for the free axle
6 is further axially moved, springs 68-1,
68-2 contracts, the key 64 is pushed down, and the concave portion 54 of the free axle switching sleeve 56 becomes the convex portion 6 of the key 64.
After passing over 6, the sleeve spline 52 meshes with the hub spline 50 of the flare axle lock portion 48, and the free axle switching sleeve 56 and the inner differential case 26 are coupled to each other, whereby four-wheel drive (4WD) is performed.
Axle lock is performed.

As a result, since the free wheel clutch 46 can be provided with the synchronizing function by the key 64 and the multi-plate clutch 72, the occurrence of gear noise can be prevented.

The multi-plate clutch 70 can provide the same effect as the viscous coupling.

Further, a free axle switching sleeve 56.
If the movement of the free axle fork 58 is adjusted by the actuator 62 when the vehicle is moved in the axial direction, the friction of the multi-plate clutch 72 can be changed and the same effect as the viscous coupling for full-time 4WD can be obtained. , It is possible to actively control the torque distribution.

[0040]

As is apparent from the above detailed description, according to the present invention, a key that is moved to the inner differential case side by the axial movement of the sleeve is provided, and the inner key is moved between the inner differential case and the outer differential case by the key movement. By providing the multi-plate clutch that is pressed through the differential case, it is possible to prevent the occurrence of gear noise by the synchronizing function.

The multi-plate clutch can provide the same effect as the viscous force coupling.

Furthermore, the effect of the viscous coupling can be changed by adjusting the pressing force of the multi-plate clutch.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a differential device.

FIG. 2 is a sectional view of a freewheel clutch.

3 is a side view of the freewheel clutch according to the arrow 〓 of FIG.

FIG. 4 is a diagram illustrating a 2WD axle-free state.

FIG. 5 is a diagram for explaining switching from 2WD to 4WD.

FIG. 6 is a diagram illustrating a 4WD axle lock operation.

FIG. 7 is a cross-sectional view of a conventional freewheel clutch.

[Explanation of symbols]

 2 differential device 24 differential case 26 inner differential case 28 first outer differential case 30 second outer differential case 56 free axle switching sleeve 64 key 72 multi-disc clutch

Claims (2)

[Claims] 1. An inner differential case for holding a differential pinion shaft and incorporating the differential pinion shaft and the differential pinion, and an outer differential case rotatable relative to the inner differential case, wherein the inner differential case and the outer case are driven during four-wheel drive. In a freewheel clutch of a four-wheel drive vehicle provided with a sleeve that is axially moved so as to be coupled with a differential case, a key that is moved toward the inner differential case by axial movement of the sleeve is provided, and the inner differential case and the A free wheel clutch for a four-wheel drive vehicle, wherein a multi-disc clutch is provided between the outer differential cases and is pressed by the movement of the key through the inner differential case. 2. The key is disposed between the sleeve and the outer case, the recess of the sleeve and the protrusion of the key are fitted to each other, and a spring for pressing the key toward the sleeve is provided. The freewheel clutch for a four-wheel drive vehicle according to claim 1, characterized in that.