JPS63242728A - Power transmission device for full-time four-wheel drive vehicle - Google Patents

Abstract

PURPOSE:To facilitate test for speedometer and exhaust gas check by permitting the spline fitting of a fluid coupling for one shaft between a driving shaft and trailing shaft to be released by the slide of the fluid coupling. CONSTITUTION:A fluid coupling 17 is slidable only in the shaft direction with respect to an output shaft 20 and a universal joint shaft 18 in the fitting part between the outer splines 24 and 26. A fork 32 is engaged with the fluid coupling 17, and the fork 32 is connected with an operating lever. When the fluid coupling 17 is shifted forwardly through the fork 32 by operating the operating lever, the fitting of the fluid coupling 17 for the outer spline 24 on the output shaft 20 side is maintained, and the fitting for the outer spline 26 on the universal joint shaft 18 side is released.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a power transmission device for a constantly four-wheel drive vehicle.

(Prior art) When a vehicle is constantly driven by four wheels, both the front and rear wheels are driven by the engine. Some vehicles are equipped with a viscous multi-disc clutch that is a fluid coupling that transmits power from the engine to the rear wheels via this fluid coupling.

The automobile with the above configuration exhibits the following functions. That is, during normal driving, power is transmitted from the engine to the front and rear wheels mainly to the front wheels, which are directly connected to the engine. but.

For example, if the front wheels get stuck in mud or crushed debris and slip and spin, the power from the engine is transmitted to the rear wheels via the fluid coupling, driving the rear wheels. . Then, the rear wheels roll on the road surface, allowing the vehicle to escape from the mud and debris.

On the other hand, when testing speedometers or checking exhaust gas during vehicle inspections or assembly lines, 1.
One of the front and rear wheels is placed on the ground and stationary on the construction surface, and the other wheel is idled to perform the above test. At this time, in order to idle the other wheel, conventional In this case, a pair of front and rear idling rollers is provided, and a wheel to be idled is placed between the two rollers.

(Problems to be Solved by the Invention) In the case of a four-wheel drive vehicle as described above, when the front wheels are placed on the idle rollers and the engine is driven,
This front wheel idles on the idle roller, but at this time,
Since the rear wheels are driven, it is not possible to test the speedometer or check exhaust gas using only the idle rollers on which the front wheels are mounted as described above.

Therefore, it is conceivable to provide idle rollers on which both the front and rear wheels can be mounted, but this would increase the equipment cost. It is also conceivable to provide a clutch for power connection/disconnection between the engine and the rear wheels in addition to the above-mentioned fluid coupling, thereby making it possible to disconnect the power transmission to the rear axle.
In this case, the structure of the power transmission device becomes complicated, which is not preferable.

(Object of the Invention) This invention was made with attention to the above-mentioned circumstances, and when trying to test a speedometer, for example,
Even if a four-wheel drive vehicle is not equipped with an idling roller that can idle only one of the front and rear wheels, it can be easily configured using only this idling roller. The purpose is to enable the above tests, etc.

(Structure of the Invention) A feature of the present invention for achieving the above object is that the fluid coupling is spline-fitted to the drive shaft on the engine side and the driven shaft on the side of one of the front and rear wheels. In a power transmission device for a constantly four-wheel drive vehicle in which these two shafts are connected, the fluid coupling is slidable in the axial direction at a spline fitting portion between the drive shaft and the driven shaft, and the sliding of the fluid coupling causes the transmission of the two shafts. The point is that the spline fitting of the fluid coupling to either one of the shafts can be released.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 2, reference numeral 1 denotes a four-wheel drive vehicle, and this vehicle 1 has a drive unit W12, and a front wheel device 3 and a rear wheel device 4 driven by this drive device 2. Also,
An arrow Fr in the figure indicates the front of the automobile l.

The drive device i2 is comprised of an engine 6 placed horizontally at the front of the vehicle body, and a transmission a7 provided in parallel with the engine 6 and operatively connected to the engine 6.

Further, the front wheel device 3 has a pair of left and right front wheels 8.8 and a front axle 9 connected to each of the front wheels 8. A front differential gear (hereinafter referred to simply as a front differential; the same applies to a rear differential to be described later) is provided to transmit power to the front wheels 8 via each front axle 9.

On the other hand, the rear wheel device 4 has a pair of left and right rear wheels 12.12, and a rear axle 13 connected to each of the rear wheels 12,
A rear differential 14 is interposed between the front and rear axles 13, 13, which inputs the power from the transmission 7 through the ring gear loa of the front differential lO, and transmits the power to the rear wheels 12 through each rear axle 13. It is.

In addition, in the above case, the ring gear 10 of the front differential lO
a and the input shaft 14a of the rear differential 14, a transfer 16, a fluid coupling 17, and a universal joint shaft 18 are interposed in this order from the drive side.

In FIG. 1, an output shaft 20 of the transfer 16 extends in the front-rear direction and is rotatably supported by a transfer case 21. As shown in FIG. The rear end of this output shaft 20 is a free end, and a collar 22 is removably fitted onto this rear end by means of a spline, and is screwed by a nut 23. An outer spline 24 is formed on the outer peripheral surface of this collar 22. On the other hand, the front end of the universal joint shaft 18 is also rotatably supported by the transfer case 21, and the front end of the universal joint shaft 18 is also a free end.
An outer spline 26 is formed on its outer peripheral surface.

The fluid coupling 17 is a viscous multi-plate clutch in the illustrated example, and 5
This fluid coupling 17 includes a drive side member 27 spline-fitted to an outer spline 24 on the side of the output shaft 20 that is a drive shaft, and an outer spline 26 on the side of the universal joint shaft 18 that is a driven shaft.
The driven side member 28 is spline-fitted to the driven side member 28.

Further, a driving disk 29 is fitted onto the driving side member 27 so as to be slidable only in the axial direction, and a driven disk 30 is fitted onto the driven side member 28 so as to be slidable only in the axial direction. Silicone oil is sealed in the space covering both of these disks 29 and 30, which are arranged alternately.

Therefore, when the output shaft 20 rotates, the drive side member 27 and the drive disk 29 rotate accordingly, and at this time,
The viscosity of the silicone oil causes the driven disk 30 to rotate, thereby causing the driven side member 28 and the universal joint shaft 1 to rotate.
Power is transmitted to the rear wheel 12 side via 8.

In the above configuration, the fluid coupling 17 is slidable only in the axial direction with respect to the output shaft 20 and the universal joint shaft 18 at the fitting portions with the both outer splines 24 and 26. Further, a fork 32 is engaged with this fluid coupling 17, and this fork 32 is connected to an operation lever (not shown).

When the fluid coupling 17 is moved forward through the fork 32 as shown by the two-dot chain line in the figure by operating the operating lever, the fluid coupling 17 remains fitted to the outer spline 24 on the output shaft 20 side. However, the universal joint shaft 18
The fitting to the side outer spline 26 is released.

That is, by this, the universal joint shaft 18 is connected from the output shaft 20 side.
The power transmission to the side is cut off, so that a state is obtained in which only the front wheels 8 can be driven.

Note that, although the above points are based on the illustrated example, when cutting off power transmission to the universal joint shaft 18 side, the fluid coupling 17 is moved backward to release the fitting of the fluid coupling 17 to the outer spline 24 on the output shaft 20 side. In addition, in the above embodiment, a fluid coupling 17 is provided between the engine 6 and the rear wheel 12.
However, this fluid coupling 17 may be interposed between the engine 6 and the front wheels 8.

(Effects of the Invention) According to the present invention, the fluid coupling can be freely slid in the axial direction at the spline fitting portion between the drive shaft and the driven shaft, and the sliding of the fluid coupling can cause the fluid coupling to move against either of the two shafts. Since the spline fitting of the fluid coupling can be released, if the spline fitting to either the drive shaft or the driven shaft is released by sliding the fluid coupling, it will be possible to release the spline fitting to either the front or rear wheels. This means that power transmission can be disconnected. Therefore, it is possible to cut off the power transmission and keep one wheel in contact with the ground, while only the other wheel is allowed to idle on the idle roller. For this reason, even if only one of the front and rear wheels is mounted on an idle roller that can be idled.

This will allow speedometer tests and exhaust gas checks.

Furthermore, when a fluid coupling is provided, it is usually spline-fitted to the drive shaft and driven shaft.

In the present invention, the splines are effectively utilized to make the fluid coupling slidable in the axial direction with respect to each axis. Therefore, when power transmission is cut off by sliding of the fluid coupling as described above, this configuration can be made simple.

[Brief explanation of drawings]

The drawings show an embodiment of the invention, in which Fig. 1 is a side sectional view of a portion provided with a fluid coupling, and Fig. 2 is an overall diagram of the automobile. 1...Car (3* *engine, 8Φ-front wheel, 1
2@. Rear wheel, 17.. Fluid coupling, 18.. Universal joint shaft (driven shaft), 20.. Output shaft (drive shaft).

Claims (1)

[Claims] 1. A fluid coupling is interposed between one of the front and rear wheels driven by the engine and the engine, and this fluid coupling is connected to the drive shaft on the engine side and the driven shaft on the one wheel side. In a power transmission device for a constantly four-wheel drive vehicle in which these two shafts are connected by spline fitting, the fluid coupling is slidable in the axial direction at the spline fitting portion of the drive shaft and the driven shaft. A power transmission device for a constantly four-wheel drive vehicle, characterized in that the spline fitting of the fluid coupling to either one of the two shafts can be released by sliding.