JPS61112843A - Four wheel drive vehicle provided with intermittent engaging mechanism for drive shaft - Google Patents

Abstract

PURPOSE:To reduce noise and abrasion and as well to enhance the economy of fuel consumption and the coverage of distance, by providing differential rotation limiting mechanisms between the input and output sides of a differential gear unit within the casing of the latter. CONSTITUTION:In the casing 20 of a differential gear unit, differential rotation limiting mechanism 50A, 50B are provided between the input and output sides of the differential gear unit. Therefore, the differential rotation of two of four wheels, which are not driven upon two wheel drive operation, may be limited without the operation of an intermittent engaging mechanism 30 and the effects given thereby being harmed. Accordingly, upon two wheel drive operation noise generated from the non-driven system and the resistance of the latter are reduced, thereby it is possible to aim at enhancing the economy of fuel consumption and the coverage of distances upon four wheel drive operation and at reducing abrasion.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a four-wheel drive vehicle that can be switched to two-wheel drive using a transfer device, and particularly relates to a four-wheel drive vehicle that is equipped with a drive shaft disconnection mechanism in such a four-wheel drive vehicle. Regarding wheel drive vehicles.

[Prior art]

As a type of four-wheel drive vehicle, a pair of drive shafts attached to both side gears of the differential, which is the non-drive side when driving two wheels, is each divided into two parts, and these divided shafts can rotate relative to each other at their ends. A four-wheel drive vehicle is provided in which a pair of split shafts are connected to each other, and the connection between the pair of split shafts is selectively interrupted by a force/knob ring member that is movably assembled in the axial direction to the connecting portion of the split shafts. be.

In this type of four-wheel drive vehicle, by cutting off the power transmission between the non-drive wheel and the drive shaft during two-wheel drive, the noise generated from the non-drive system is reduced, and the rotational resistance of the non-drive system is reduced. This aims to improve fuel efficiency and reduce wear.

In addition, in such four-wheel drive vehicles, the drive shaft disconnection mechanism is provided by a differential carrier as shown in the specifications and drawings of U.S. Patent No. 4.271.722, Utility Model Application Publication No. 58-135322, etc. located on one side of the differential.

[Problem that the invention seeks to solve]

By the way, in conventional four-wheel drive vehicles of this type, since the differential does not have a function to limit the differential, the running performance during four-wheel drive running tends to be slightly inferior. For this reason, it is desirable that the differential has a function of limiting the differential only during four-wheel drive.

[Means for solving problems]

In order to deal with this, the present invention provides this type of four-wheel drive vehicle with a differential limiting mechanism between the input side and the output side within the case of the differential.

[Action/effect of the invention]

As a result, in the present invention, it is possible to limit the differential during four-wheel drive of the differential, which is on the non-drive side during two-wheel drive, without impairing the operation of the drive shaft disconnection mechanism and the effects brought about by the mechanism. can.

Therefore, according to the present invention, the noise generated from the non-drive system during two-wheel drive can be reduced, and the rotational resistance of the non-drive system can be reduced to improve fuel efficiency and reduce wear. It is possible to improve running performance during wheel drive.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 schematically shows a four-wheel drive vehicle according to a first embodiment of the present invention. This four-wheel drive vehicle has a front engine.
It is a four-wheel drive vehicle based on the front drive system (FF vehicle), and in this vehicle, the transaxle 12 integrated with the transfer installed at the rear of the engine 11,
Both front axle shafts 13 can be driven at all times, and power transmission to the propeller shirt 14 can be switched on and off using a transfer switching mechanism. Therefore, in this vehicle, both rear axle shafts 15
is on the non-drive side during two-wheel drive, and both rear axle shafts I5 are connected to the propeller shaft 14 via a differential 20 integrated with the final gear.

The differential 20 is, as shown in FIG. The differential case 23 is integrally supported by the differential case 23, and the differential case 23 is rotatably supported by the differential carrier 21. This ring gear 22 is constantly meshed with a drive pinion 24 connected to the propeller shaft 14. The differential gear unit also includes two sets of pinion gears 26 assembled to the differential case 23 via a pinion shaft 25, and
It consists of a pair of side gears 27 that are rotatably supported by the pinion gear 26 and always mesh with the pinion gear 26. A drive shaft 28, 29 that constitutes a part of each rear axle shaft 15 is spline-fitted to each side gear 27. ing. Of these drive shafts 28 and 29, the drive shaft 28 on the right side of the drawing is a long one, which penetrates the differential carrier 21 in a fluid-tight and rotatable manner, protrudes from the extension tube 16, and has the rear axle shaft 15 attached to its outer end. The main shafts 15a constituting the main shafts are connected.

In addition, the illustrated left drive shaft 29 is shorter than the right drive shaft 28, and protrudes through the differential carrier 21 in a liquid-tight and rotatable manner, and has a main shaft that constitutes a rear axle shaft '15 at its outer end. shaft 1
5b are connected.

The right drive shaft 28 is divided into an inner shaft 28a and an outer shaft 28b, and both shafts 1-28a and 28b are connected at their ends so as to be relatively rotatable. shirt) 28a,
The connection of 28b is interrupted. Furthermore, the left drive shaft 29 includes an inner shaft 29a and an outer shaft 29b.
The connection between these two shafts (29a and 29b) is interrupted by the disconnection mechanism 30.

The disconnection mechanism 30 includes a compulsory sleeve 31 as a first coupling member, a coupling rod 32 that also serves as the inner shaft 29a as a second coupling member, an operating rod 33, an operating lever 34, and first and second springs. Both compression springs 35, 36 and connecting rod 3 as members
7 is the main component.

The compression sleeve 31 has both shafts 28a.

An outer spline 28al is provided on the outer periphery of the end portion of 28b.

The inner shaft 28b1 is provided with an inner spline 31a that meshes with the outer spline 28al of the inner shaft 28a, and is assembled to be movable in the axial direction by meshing with the outer spline 28al of the inner shaft 28a.

The coupling sleeve 31 connects and disconnects the outer shaft 28b to the inner shaft 28a by moving in the axial direction, and is operated by an operating lever 34 assembled on an operating rod 33.

The coupling rod 32 also serves as the inner shaft 29a of the left drive shaft 29, and is used as the inner shaft 29a of the left drive shaft 29.
7 so as to be slidable only in the axial direction, and rotatably fitted to the outer shaft 29b. The outer end of the coupling rod 32 is provided with an outer spline 32a that engages and disengages with an inner spline 29b1 provided on the outer shaft 29b.
Both shafts 29a, 29b1 by sliding in the axial direction of 2
That is, the connection between the outer shaft 29b and the side gear 27 is disconnected. Note that the coupling rod 32 is connected to the coupling sleeve 31 via a connecting rod 37, which will be described later.

The actuating rod 33 is attached to an example of the output end of the differential carrier 21 so as to be movable in the axial direction in parallel with the drive shaft 28, and an inner wire 41 of a push-pull cable is connected to one end of the actuating rod 33. . The actuating rod 33 is reciprocated by the operation of a push-pull cable, and is intermittently reciprocated by a predetermined amount by the action of the detent mechanism 42. The operating lever 34 is attached to the outer periphery of the operating rod 33 at a cylindrical base 34a so as to be movable by a predetermined amount in the axial direction, and a portion 34b of the lever faces into the differential carrier 21 and is always engaged with the compression sleeve 31. It matches. The outer periphery of the operating rod 33 and the cylindrical base 3 of the operating lever 34
A compression spring 35 is interposed between 4a. This compression spring 35 is always compressed in the moving direction when the actuating rod 33 moves, and its reaction force urges the operating lever 34 in the moving direction of the actuating rod 33.

The connecting rod 37 is fitted into the inner shafts 28a, 29a so as to be slidable concentrically and axially, and a cross rod 37a is implanted at the right outer end thereof. The cross rod 37a protrudes from a pair of slit holes 28a2 provided in the inner shaft 28a in the radial direction, and is connected to the coupling sleeve 31. Further, the left outer end of the connecting port 37 is connected to the outer end of the coupling loft 32 via a compression spring 36. This compression spring 36 is always compressed in the moving direction when the connecting rod 37 moves, and its reaction force urges the coupling rod 32 in the moving direction of the connecting rod 37.

Incidentally, reference numeral 43 indicates an inch that is actuated when the actuating rod 33 moves to connect both the drive shafts 28 and 29.

Therefore, differential limiting mechanisms 50A and 50B are provided within the differential case 23 of the differential 20. The differential limiting mechanisms 50A, 50B include a large number of friction plates 51a, 51b and friction discs 52a, 52.
Each friction plate 513151b is attached to the outer periphery of the cylindrical portion of each side gear 27 to be slidable in the axial direction on the inner periphery of the differential case 23 and rotatable therewith. In addition, each friction disk 52a, 52
b are arranged alternately between the friction plates 51a and 51b, and are attached to the outer periphery of the cylindrical portion of each side gear 27 so as to be slidable in the axial direction and rotatable therewith. Further, a compression spring 53 is interposed in the inner hole of the cylindrical portion that is the common base of each pinion shaft 25. This compression spring 53 presses each side gear 27 via each retainer 54a, 54b, and each friction plate 51
a, 51b are brought into contact with friction disks 52a, 52b.

When the vehicle configured in this way is in two-wheel drive,
As shown in FIG. 2, the coupling of each drive shaft 28, 29 is interrupted. Therefore, each rear wheel only rotates the outer shafts 28b, 29b of each drive shaft 28, 29, and the constituent members of the differential 20,
The propeller shaft 14 etc. are not driven. Therefore, the noise generated from the non-drive system is reduced, and
By reducing the rotational resistance of the non-drive system, it is possible to improve fuel efficiency and reduce wear.

On the other hand, when the vehicle is in four-wheel drive, the push-pull cables are operated in advance to drive both shafts 28a of each drive shaft 28, 29.

28b, 29a, and 29b are combined. When the inner wire 41 of the push-pull cable is pulled to the right in the second figure, the actuating rod 33 is intermittently moved to the right by a predetermined amount by the action of the detent mechanism 42, deflecting the compression spring 35, and moving the actuating rod 33 through the operating lever 34. to urge the compression sleeve 31 to the right.

In this case, if the rotations of the coupling sleeve 31 and the outer shaft 28a are synchronized, the coupling sleeve 31 smoothly meshes with the outer shaft 28b to couple the outer shaft 28b to the inner shaft 28a. In addition, the coupling sleeve 31 and the outer shaft 2
When the rotation with 8b is not synchronized, the coupling sleeve 31 resiliently contacts the outer shaft 2Bb side, waits temporarily, and then engages with the outer shaft 28b to couple it to the inner shaft 28a. do. Furthermore, the movement of the coupling sleeve 31 causes the connection rod 37 to move in the same direction, bending the compression spring 36, and biasing the coupling rod 32 (inner shirt) 29a) to the right. In this case, if the rotations of the coupling rod 32 and the outer shaft 29b are synchronized, the coupling rod 32 smoothly meshes with the outer shaft 29b to couple the outer shaft 29b to the inner shaft 29a. Further, when the rotations of the compling rod 32 and the outer shirt l-29b are not synchronized, the compling rod 32 resiliently contacts the outer shaft 29b side, waits temporarily, and then the outer shaft 29b This is connected to the inner shaft 29a by meshing with the inner shaft 29a. As a result, the power input from the drive pinion 24 is output to both drive shafts 28 and 2.9, resulting in four-wheel drive.

Note that when switching to two-wheel drive, when the inner wire 41 is pushed, the disconnection mechanism 30 performs an operation opposite to that described above to interlock and disconnect the connections of the drive shirts 28 and 29, respectively.

However, in this four-wheel drive mode, both side gears 27
If the rotational speed between the gears is different, that is, both gears
7 and the differential case 23, friction torque is generated between each friction plate 51a, 51b and each friction bond disc 52a, 52b. As a result, the drive torque on the low-speed side of both side gears 27 increases, and the drive torque on the high-speed side decreases, thereby preventing a drop in driving performance. That is, running performance during four-wheel drive is improved.

As described above, according to this embodiment, the noise generated from the non-drive system during two-wheel drive can be reduced, and the rotational resistance of the non-drive system can be reduced to improve fuel efficiency and reduce wear. Of course, it is possible to improve running performance during four-wheel drive.

Furthermore, in this embodiment, the coupling sleeve 31
A connecting rod 37 that connects the and coupling rod 32
is fitted into the inner shafts 28a, 29a so as to be able to slide concentrically and axially, so there is no need to extend the actuating rod 33 to the vicinity of the outer shaft 29b, and there is no compression sleeve on the actuating rod 33. What is necessary is to assemble one operating lever 34 for operating 31.

For this reason, the differential carrier 21 may be exactly the same or approximately the same size as a normal differential carrier, and the differential carrier 21
The increase in size is prevented.

FIG. 3 shows a four-wheel drive vehicle according to a second embodiment of the invention. This four-wheel drive vehicle is a four-wheel drive vehicle based on a front engine/rear drive (FR vehicle), and in this vehicle, both rear axles can be constantly driven by a transmission 12a and a transfer 12b installed at the rear of the engine 11. At the same time, power transmission to the propeller shaft 14 is switched on and off using a switching mechanism of the transfer 12b. Therefore, in this vehicle, both front axles (3) are on the non-drive side during two-wheel drive, and the front differential 20A is similar to the differential 20 of the first embodiment. In addition, in FIG. 3, the reference numeral 20B is a rear differential.

In the present invention, a known differential limiting mechanism can be used as appropriate, and a compression spring 36 with a large amount of deflection can be used to prevent the coupling rod 37 from moving when the coupling rod 32 is on standby. It is also possible to make the stroke longer.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of a four-wheel drive vehicle according to a first embodiment of the present invention, FIG. 2 is an enlarged cross-sectional plan view of a differential in the same vehicle, and FIG. 3 is a four-wheel drive vehicle according to a second embodiment. FIG. Explanation of symbols 20.20A, 20B...Differential, 21
...Differential carrier, 27...Side gear, 28.2
9... Drive shaft, 28a, 28b, 29a
, 29b---divided shaft, 30... intermittent mechanism, 3
DESCRIPTION OF SYMBOLS 1... Coupling sleeve, 32... Coupling rod, 33... Operating rod, 34... Operating lever, 35.36... Compression spring, 37... Connecting rod, 42... Detent mechanism, 50A, 50B・
...Differential limiting mechanism.

Claims (1)

[Claims] A pair of drive shafts attached to both side gears of a differential on the non-drive side during two-wheel drive are each divided into two parts, and these divided shafts are connected at their ends so that they can rotate relative to each other. In a four-wheel drive vehicle in which the connection between the pair of split shafts is selectively disconnected by a coupling member that is movably assembled in the axial direction to the connecting portion, the input side and A four-wheel drive vehicle equipped with a drive shaft disconnection mechanism characterized by a differential limiting mechanism provided between output sides.