JPH0226345A - Power transmission - Google Patents

Abstract

PURPOSE:To make it hard to generate vibration, attenuate the load to a propeller shaft and eliminate the need for specially mounting a support part by mounting a connection and disconnection device which connects and disconnects the output terminal of a viscous coupling to the differential case of a differential device. CONSTITUTION:When a connection and disconnection device 113 is put into the connection state, the output terminal of a viscous coupling 65 is connected to the differential case 67 of a differential device 87 so that the input torque is delivered thereto via the viscous coupling 65. The differential torque is distributed to the load side from the differential mechanism of this differential device 87. At this time when the difference between the revolution speeds at the input and the output of the viscous coupling 65 grows due to the input to the viscous coupling 65 and the load to the differential device 87, the differential revolution is limited greatly so that the high torque is transmitted to the differential device 87.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a power transmission device used in a vehicle or the like.

(Prior Art) Japanese Patent Application Laid-Open No. 172764/1983 shows, for example, a front engine/front drive (FF) based 4WD vehicle, in which a viscous clutch (viscous coupling) is installed on the propeller shaft of the rear wheel drive system. ) and an interrupter are arranged.

(Problems to be Solved by the Invention) As described above, when power transmission is interrupted and interrupted on a propeller shaft that is relatively long and has a high rotational speed, the moment of inertia becomes large and vibrations are likely to occur. For this reason, when disposed on the propeller shaft, a special support must be provided.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a power transmission device that hardly generates vibrations, does not increase the load on the propeller shaft, and does not require a special support part.

→←−−−− (Structure of the Invention) (Means for Solving the Problems) In order to solve the above problems, the power transmission device of the present invention combines a viscous coupling and a differential that transmit torque through viscous fluid. The viscous coupling is integrally assembled with the viscous coupling and the differential case of the differential device is connected to the output side of the viscous coupling.

(Function) When the disconnection device is connected, the output side of the viscous coupling and the differential case of the differential device are connected, and the input torque is transmitted to the differential 7 through the viscous coupling.
The signal is transmitted to the differential gear and differentially distributed from the differential mechanism of the differential device to the load side. At this time, if the rotational difference between the input side and the output side of the viscous coupling increases due to the input to the viscous coupling and the load on the differential device, this rotational difference is greatly limited and a large torque is transmitted to the differential device. Furthermore, when the rotational difference becomes smaller, this rotational difference is allowed and the transmitted torque becomes smaller. When the disconnection device is placed in a disconnected state, power transmission between the viscous coupling and the differential device is interrupted.

Furthermore, since the viscous coupling and the differential device are arranged integrally, it is advantageous in terms of support and the like.

(Example) The first embodiment will be explained with reference to FIGS. 1 and 2.

FIG. 2 shows a drive configuration of an FF-based 4WD vehicle using the differential device section of the power transmission device of this embodiment as a rear wheel side differential device (rear differential). The upper half of FIG. 1 shows the locking state of the interrupter, and the lower half shows the free state.

Note that in the following description, the left and right directions refer to the right and left directions in the left and right vehicle width directions in these drawings.

First, the power transmission of this vehicle will be explained with reference to FIG. The driving force of the engine 1 is shifted by the transmission 3,
The signal is transmitted to the differential case of the front wheel side differential device (front differential) 7 housed in the transfer 5, and differentially distributed directly to the left and right front wheels 13, 15 via the front axles 9, 11. On the other hand, the driving force of the engine 1 is transmitted through the differential case, a 2-4 switching mechanism housed in the transfer 5, and a direction conversion gear set (none of which are shown) that disconnects and disconnects power transmission to the rear wheels. The power is transmitted to the power transmission device 19 of the embodiment. The rear differential of the power transmission device 19 differentially distributes the transmitted driving force to the left and right rear wheels 25.27 via the rear axle 21.23.

Next, the configuration of this embodiment will be explained using FIG. 1.

The outer case 29 includes a case body 31 and its cover 33.
It is rotatably supported via bearings (none of which are shown) in a differential carrier that houses the rear differential. The case body 31 is provided with a flange portion 35, and the propeller shaft 17 is attached to this flange portion 35.
A bolt hole 37 is provided for bolting a ring gear that meshes with a drive pinion gear connected to the side and forms a final reduction gear set together with the drive pinion gear. In this way, the outer case 29 is rotationally driven by the driving force from the engine 1.

Inside the outer case 29, a shaft support 39 is formed in the cover 33, and a hub member 41 is attached to this shaft support 39.
is rotatably supported. A working chamber 43 is formed between the hub member 41 and the case body 31, and is filled with a viscous fluid, such as silicone oil. This working chamber 43
Inside the case body 31, a spline 45 and a spline 47 are provided on the hub member 41, respectively. A plurality of outer plates 49 are engaged with the spline 45, and a plurality of inner plates 51 are engaged with the spline 47 in the rotational direction. These plates 49, 51 are arranged alternately, and spacers 53 are arranged between each outer plate 49 to maintain an appropriate gap between them. Further, a ring 55 is arranged on the right end side of the working chamber 43, and a spline 57 provided on the outer circumference of the ring 55 is engaged with the spline 45. This ring 55
An X-ring 59 as a rubber seal with an X-shaped cross section is installed between the hub member 41 and an O-ring 61 between the case body 31 and the case body 31.
An X-ring 63 is disposed on the shaft support 39 between the cover 33 and the hub member 41 to maintain the working chamber 43 in a liquid-tight state. In this way, the viscous coupling 65 is constructed.

Inside the outer case 29, a differential case 67 is disposed on the right side of the viscous coupling 65, and is rotatably supported by the case body 31 via a bush 69. Four axial grooves 71 are provided on the inner periphery of the differential case 67, and each end of a binion shaft 73 arranged in a cross shape is engaged with each groove 71 in the rotational direction. Therefore, the differential case 67 is rotatable together with the binion shaft 73 and can be moved relative to the case body 31 and the binion shaft 73 in the axial direction.

Four pinion gears 75 are rotatably supported on each of the pinion shafts 73, and side gears 77 and 79 are arranged coaxially on the left and right sides of the pinion gears 75 and mesh with the pinion gears 75, respectively. A washer 81 is arranged between the differential case 67 and the pinion gear 75,
A washer 8 is installed between the hub member 41 and the left side gear 77.
3, and washers 85 are arranged between the case body 31 and the right side gear 79, respectively. In this way, the rear differential 87 is configured. left side gear 7
7 is a transmission shaft connected to the left rear axle 21 via a joint, and father's side gear 79 is a transmission shaft connected to the right rear axle 23 via a joint (both the joint and the transmission shaft are shown in the figure). (not shown) are connected by splines.

A spline 89 is provided on the outer periphery of the right end of the hub member 41, and a spline 91 that can engage with the spline 89 is provided on the inner periphery of the left end of the differential case 67. Further, a retainer 93 is integrally provided on the right end side of the differential case 67, and a retainer 95 is provided on the washer 81 side.

The case body 31 is provided with a plurality of windows 97 in a cylindrical arrangement. Further, a small diameter portion is formed on the outer periphery of the right end portion of the case body 31, and nine slide rings are housed in this small diameter portion so as to be movable in the axial direction. slide ring 99
is integrally provided with a plurality of arms 101, and these arms 1
01 passes through the window 97 and is in contact with the retainer 93 via the second dollar bearing 103. A return spring 105 is installed between the retainer 93 and the retainer 95 to urge the differential case 67 to the right. Further, a two-pronged fork 107 is slidably engaged with the outer periphery of the slide ring 99. A protrusion 109 that abuts against the fork 107 is provided on the left side of the ring 99. Therefore, if the fork 107 is moved to the left against the biasing force of the return spring 105, the differential case 67 will move to the left as the slide ring 99 moves. Case body 31
The stepped portion 111 formed between the small diameter portion and the large diameter portion acts as a stopper at this time, and prevents the ring 55 from coming into contact with the differential case 67 that has moved to the left. In this way, the disconnection device 113 is configured.

Due to the biasing force of the return spring 105 of the disconnection device 113 and the operation of the fork 107, the differential case 67 reciprocates between the left connection position and the right release position. When the differential case 67 moves to the connecting position, it is connected to the hub member 41 by engagement of the splines 89 and 91. Also differential case 6
7 moves to the release position, the connection with the hub member 41 is released.

Such operation of the disconnection device 113 is performed manually from the driver's seat, or by adjusting the steering angle, gear shifting force, and braking force 12-4.
It is configured to be able to be automatically operated in accordance with the operation of the switching mechanism.

Next, the function of this practical example will be explained.

When the disconnection device 113 is in the connected state as shown in the upper half of FIG. 1, the driving force from the engine 1 is transmitted to the rear differential 87 via the viscous coupling 65. At this time, if a large rotation difference occurs between the outer case 29 of the viscous coupling 65 and the hub member 41 due to the balance between the driving force from the engine 1 and the load on the rear wheel 25, 27 side, the viscous coupling 65 Due to the characteristics, differential rotation is greatly limited and large driving force is transmitted to the rear wheels 25.
．． 27 side. Further, in a state where the rotation difference is small, a large differential rotation is allowed, and the transmitted torque becomes small.

When the disconnection device 113 is set to the resolved state as shown in the lower half of FIG. 1, the power transmission between the viscous coupling 65 and the rear differential 87 is cut off, and the rear wheels 25 and 27 are placed in a free rotation state.

Next, functions corresponding to the performance of the vehicle shown in FIG. 2 will be explained.

First, when the disconnection device 113 is brought into the connected state, the vehicle has a drive configuration equivalent to a full-time 4WD vehicle as described below. In other words, under normal driving conditions where the difference in rotation between the front wheels 13.15 and the rear wheels 25.27 is small, the torque transmitted by the viscous coupling 65 is small, and therefore the vehicle is essentially a FF-based two-wheel drive (2WD) vehicle. It runs with such a driving force distribution state. However, if the front wheel 13.15 slips and the load on the rear wheel 25.27 side becomes relatively large, as described above, a large driving force is distributed to the rear wheel 25.27 side as well, and the vehicle runs smoothly. Run to.

Also, when making a low distance turn such as parking a garage, the rotation difference between the front and rear wheels is small, so this rotation difference is compensated for by the viscous coupling 6.
5, twisting of the propeller shaft 17 does not occur, and therefore tight corner braking phenomenon is prevented.

In addition, the front wheel 13.15 side is directly driven, and the rear wheel 2
5. Since the 27 side is configured to be driven via the viscous coupling 65, when the rotation difference between the front and rear wheels becomes large, vehicle safety and steering stability are affected as described above. Improves performance, drivability, etc.

When the disconnection device 113 is released, the vehicle becomes fully 2WD.
The vehicle is in running condition and has the same performance as a front-wheel drive vehicle.

If the 2-4 switching mechanism of the transfer 5 is switched to the 2WD side in this 2WD running state, the rotation of the direction conversion gear set and the propeller shaft 17 in the drive system on the 25° 27 side of the rear wheels is stopped. Therefore, wear of various parts, noise, vibration, and reduction in fuel efficiency caused by these unnecessary rotations are prevented, and the same effects as a freehub clutch can be obtained.

In this manner, since the power transmission device 19 is not disposed on the propeller shaft 17, the eccentricity can suppress an increase in the moment of inertia of the propeller shaft 17 as in the conventional example, and vibration can be prevented. Further, the propeller shaft 17 is not separated, and there is no need to provide a support part for the device in the middle of the propeller shaft 17.

Further, since the viscous coupling 65 and the rear differential 87 are arranged axially with respect to each other, and the hub member 41 is made smaller in diameter than the differential case 67, the power transmission device 19 is made smaller in the radial direction. Therefore, when used in a vehicle power transmission system as in this embodiment, the minimum ground clearance can be increased, which is advantageous.

Furthermore, since the viscous coupling 65 has a small diameter and the relative rotational speed between its input and output members is reduced, it is easy to improve the durability of the X-ring 59.63.

Next, a second embodiment will be explained with reference to FIG. The power transmission device 115 of this embodiment is provided in the same position as the first embodiment in the vehicle shown in FIG.

In FIG. 3, the upper half shows the connected state of the device 115, and the lower half shows the released state. Hereinafter, differences from the first embodiment will be explained while referring to the same members with Shuichi numbers. Note that the left and right directions are the left and right directions in FIG. 3.

A rear differential 117 is arranged to the right of the viscous coupling 65, and a spline 121 that can engage with the spline 89 of the hub member 41 is provided on the inner periphery of the left end of the differential case 119.

Further, a convex portion 123 is provided on the right end of the outer periphery, and a stopper ring 125 is engaged and fixed on the left end. A bush 127 is movably engaged between the convex portion 123 and the stopper ring 125. The differential case 119 is rotatably engaged with a case body 129, which together with the cover 33 constitutes a seven outer case 128, via this bush 127. Similarly to the first embodiment, the differential case 1
The tip of the pinion shaft 73 is engaged in the groove 71 provided on the inner periphery of the pinion shaft 73 in the rotational direction. Therefore, the differential case 119 is rotatable together with the binion shaft 73 and is movable in the axial direction with respect to the binion shaft 73 and the case body 129.

The case body 129 is provided with a plurality of windows 131 arranged equidistantly around the circumference, and the bushing 127 is provided with an outer circumferential groove 133. The tip of the two-pronged fork 135 is the sleeve 1
37, this sleeve 137 passes through the window 131 and engages in the outer circumferential groove 133 of the bushing 127. In this way, the disconnection device 139 is configured.

By operating the disconnection device 139, the fork 135 is moved to the left (connection position) as shown in the upper half of FIG.
19, the driving force from the engine 1 is transmitted to the rear differential 117 via the viscous coupling 65. Also, as shown in the lower half of Figure 3, fork 135,
When moved to the right (released position), the connection between the hub member 41 and the differential case 119 is released, and torque transmission from the viscous coupling 65 to the rear differential 117 is interrupted.

In the case of this intermittent operation 139, the fork 135 is operated to move left and right. The interrupter 139 is configured to be manually or automatically operable as in the first embodiment.

Other functions and effects are the same as those in the first embodiment.

In addition, in this invention, it is also possible to configure so that the torque of the engine 1 is inputted from the hub member side of the viscous coupling, contrary to the above embodiments.

Although the above description has been given of an example in which the power transmission device is disposed on the rear wheel side of a 4WD vehicle, the power transmission device of the present invention can also be disposed on the front wheel side of a 4WD vehicle. In this case, the rear wheels are on the direct drive side, and the front wheels are driven via a viscous coupling. Further, the viscous coupling can also be arranged on the outer peripheral side of the differential device.

〔Effect of the invention〕

As described above, in the power transmission device of the present invention, there is no need to separate and arrange the propeller shaft. Therefore, there is little vibration, and there is no need to provide a separate support section.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the first embodiment, FIG. 2 is a schematic diagram showing power transmission in a vehicle using the first or second embodiment, and FIG. 3 is a sectional view of the second embodiment. 65...Viscous coupling, 67.119...
Differential case, 87,117...differential device, 113,139...intermittent device

Claims (1)

[Claims] A viscous coupling that transmits torque through viscous fluid and a differential device are integrally assembled, and a disconnection device is provided to disconnect and disconnect the connection between the output side of the viscous coupling and the differential case of the differential device. A power transmission device characterized by: