JPH01233123A - Driving power transmitting/cut-off device for four-wheel drive vehicle - Google Patents

Abstract

PURPOSE:To integrally form a various coupling and a driving power connecting/ disconnecting device by forming a working chamber from a number of rotary members and housing the viscous fluid and engaging a plurality of resisting plates and a casing with each rotary member in connection/disconnection abled state. CONSTITUTION:An outer case 3a is installed onto a ring gear 2 meshed with a drive pinion gear 1, and an inner case 3b is fitted into the outer case 3a. Inside the inner case 3b, a plurality of hubs 4 and 5 are housed in the relative revolution abled state, and a working chamber 7 in which viscous fluid is sealed is formed. Inside the working chamber 7, a plurality of resisting plate 8 and 9 and a spacer 10 are housed, and a plurality of working chambers 11 and 12 are formed. A driving member 17 is fitted into one supporting cylinder part 16a in the inner case 3b, in slidable manners for one driving shaft 6b. While, a fork 20 is fitted into the driving member 17.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) This invention is incorporated into the drive power transmission system of a four-wheel drive vehicle capable of switching between two-wheel drive and four-wheel drive, and It has a viscous coupling function using
The present invention relates to a drive power transmission/disconnection device for a four-wheel drive vehicle that connects and disconnects driving force.

(Prior art) Conventionally, in four-wheel drive vehicles that transmit torque from an internal combustion engine to the front and rear wheels, a so-called tie 1~: no braking phenomenon occurs when parking, etc. . For this reason, this four-wheel drive vehicle is equipped with a differential device that absorbs the difference in rotational speed that occurs between the front wheel drive shaft and the rear wheel drive shaft.

By the way, if the front wheels slip into a muddy or other road surface with a small coefficient of friction while the vehicle is running, the torque from the internal combustion engine and the structure of the differential will be the same for both the front and rear wheels as if they were wheels with a small coefficient of friction. Torque is transmitted (only 1.5 m) is transmitted, making it impossible to get out of the mud quickly.
j;) This four-wheel drive vehicle is equipped with a differential limiting device to prevent There is a viscous coupling as a differential device ([Automotive Engineering] 198
(See June 7th issue, page 62).

On the other hand, a par 1-time four-wheel drive vehicle is equipped with a transfer that selects between two-wheel drive and four-wheel drive. When two-wheel drive is performed by the transfer, the driven side power transmission system on the non-drive side (referring to the dynamic horn transmission system from the transfer to the driven wheels) is
5, the driven wheel rotates as the wheel rotates. When the driven power transmission system is rotated in this manner, the running resistance of the vehicle increases, and the vehicle suffers from vibrations, noise, and the like.

Therefore, during C1 two-wheel drive, the driven side power transmission system is partially cut off, and the rotating driven side is left in a free state, reducing the running resistance, vibration, noise, etc. as much as possible.
Driving force intermittent device for reducing νq wheel drive vehicle
215428) is being considered.

(Problem to be solved by the invention) However, in a four-wheel drive vehicle using the former type of viscous coupling, it is difficult to absorb the difference in rotational speed between the front wheel drive shaft and the rear wheel drive shaft. Although it is possible to quickly escape from muddy areas, the four wheels are always driven by the rotation of the engine, resulting in poor fuel efficiency when the vehicle is running.

On the other hand, in the case of the latter, which uses a driving force intermittent device for four-wheel drive vehicles, it is possible to improve fuel efficiency compared to two-wheel drive, but it also reduces running resistance and vibration due to the rotation of the driven power transmission system.・Although it is possible to reduce noise etc. as much as possible, when driving in four-wheel drive, it is not possible to absorb the difference in rotation speed between the front wheel drive shaft and the rear wheel RA shaft, resulting in the tight corner braking phenomenon. This caused the vehicle to run unsmoothly.

[Structure of the Invention] (Means for Solving the Problems) In order to solve such problems, the present invention provides a first rotating member J and a second rotating member disposed on the same axis. a member, a third rotating member disposed to be relatively rotatable with the first rotating member and the second rotating member, and the third rotating part is defined by the first rotating member and the second rotating member and has a viscous a working chamber in which a fluid is sealed; a first resistance plate and a second resistance plate housed in the working chamber and alternately engaged with the first rotating member, the second rotating member, and the third rotating member; This configuration includes a casing that is rotatably provided relative to the third rotating member and to which torque is transmitted, and a drive member that is provided that allows the casing and the third rotating member to move toward and away from each other.

(Function) This device is interposed between the propeller shirt 1 and the rear wheel drive shaft. When driving in two-wheel drive, the drive member is moved,
If the connection between the casing and the third rotating member is cut off, the drive system from the casing to the transfer will not be driven in the opposite direction of the torque flow, thereby improving fuel efficiency. Also, during four-wheel drive driving, if the drive member is moved and connected to the casing and the third rotating member,
In addition to making four-wheel drive possible, the tight corner braking phenomenon is prevented; roughly speaking, even if one wheel slips, the other wheel will push the vehicle, and if one wheel slips behind the other wheel on the right side, The vehicle is pushed out by the wheels used, and the vehicle runs stably. Therefore, this driving force transmission/disconnection device for a four-wheel drive vehicle can improve fuel efficiency due to two-wheel drive, and can also prevent tight corner braking.

(Example) The present invention will be explained below based on the drawings.

FIG. 1d3 and FIG. 2 are diagrams showing an embodiment of a driving force transmission/disconnection device for a four-wheel drive vehicle according to the present invention. The drive power transmission/disconnection device of a four-wheel drive vehicle is an example of F's interposed device in place of the differential gear device installed between the propeller shirt 1~ of the base four-wheel drive vehicle and the rear wheel drive shaft. be.

First, I will explain the configuration.

Reference numeral 1 denotes a drive pinion gear through which 1 to 1 torque from the internal combustion engine is transmitted and reached through the propeller shirt I. This drive pinion gear 1 meshes with a ring gear 2, and this ring gear 2 serves as a road as a casing. Outer case 3
Inside the outer case 3a, there is an inner case 3 which has a substantially cylindrical shape between the outer case 3a and the third rotating member.
The inner case 3b rotatably supports the outer case 3a.

A first hub 4 as a first rotating member and a second hub 5 as a second rotating member are housed in the inner case 3b so as to be relatively rotatable. are disposed on the same axis, and are spline-connected to the left wheel drive shaft 6a and the right wheel drive shaft @6b, respectively, which are the rear wheel drive shafts. A working chamber 7 is defined by the inner case 3b', the first hub 4, the second hub 5, etc., and this working chamber 7 is filled with silicone oil as a viscous fluid. The working chamber 7 has a first resistance plate 8 and a second resistance plate 8.
A resistive plate 9 is housed therein, and the first resistive plate 8 and the second resistive plate 9 are alternately spline-coupled to the inner case 3b, the first hub 4, and the second hub 5, respectively. A spacer 10 is disposed at approximately medium heat in the working chamber 7, and the spacer 10 divides the working chamber 10 into a first working chamber 11 and a second working chamber 12. Here, the inner case 3b, the 1st and 2nd hubs 4 and 5, the 1st and 2nd resistance plates 8 and 9 of the working chamber 7, and the silicone oil collectively function as a conventional viscous coupling.

The outer coos 3a has first support cylindrical parts 15a and 15b rotatably supported by the differential carrier 14 via bearings 13 at the left and right ends in FIG. In addition, an inner case 3 is provided on the inner peripheral side of the first support cylindrical portions 15a and 15b.
The second support cylindrical portions 16a and 16b of b are located. The right end of the second support cylindrical portion 16a is connected to the first support cylindrical portion 15a.
1, and a substantially annular drive member 17 is provided on the outer peripheral side of the extended second support cylindrical portion 16a in the axial direction of the right wheel drive shaft 6b (see FIG. 1). It is spline-fitted so that it can slide in the left and right directions. The first supporting cylindrical portion 15a and the driving member 17 are opposed to each other, and a pair of teeth 18, 19 (engaging portions) are respectively formed on the opposite sides thereof, so that they can mesh with each other. A fitting groove 178 is formed on the outer circumferential side of the driving member 17, and the fork 20 is fitted into this fitting groove 178. When the fork is slid by a moving mechanism (not shown), the driving member 17 is moved. Teeth 19 and 1st
It meshes with the teeth 18 of the support cylindrical portion 15a. Here, the outer case 3a, the inner case 3b, the drive member 17, and the teeth 18, 19 as a whole have the function of a conventional driving force disconnection device for a four-wheel drive vehicle. Roughly speaking, there is a gap 21 between the outer case 3a and the inner case 3b.
Next, the effect will be explained.

In a front-wheel drive four-wheel drive vehicle, when operating the transfer to drive in two-wheel drive (two-wheel drive), the fork 20 is moved by the moving mechanism, and the drive member 17 is moved to the right in FIG. Sliding away.

Therefore, the drive member 17 is in a state separated from the first support cylindrical part 15a, and the teeth 1'9 of the drive member 17 and the teeth 18 of the first support cylindrical part 15a are not engaged, but in an engaged state. is blocked. Therefore, the right rear wheel rotates by 8 degrees and the left and right side wheel drive shafts 5a.

6b, and further rotate the first and second hubs 4 and 5, and the first and second hubs.
All that is required is to rotate the resistance plates 8, 9 and the inner case 3b. That is, the left and right wheel drive shafts 6a, 6b, the first
, 2 hubs 4, 5, first and second resistance plates 8, 9, and inner case 3b only idle, but do not rotate outer case 3a, ring gear 2, and drive pinion gear 1. As a result, the drive system from the outer shaft 3a, ring gear 2, drive pinion gear 1 to the transfer is not driven in the opposite direction of torque flow, reducing the rotational resistance of this drive system, and It is possible to substantially improve fuel efficiency and reduce wear without causing stirring resistance of the lubricating oil that has flowed into the carrier 14. In addition, noise generated from the drive system can be reduced.

Next, when operating the transfer and traveling in four-wheel drive, the moving mechanism moves the A-ri 20 and slides the L drive member 17 to the left in FIG. Drive member 17
When the rotations of the outer case 3a and the outer case 3a are synchronized, as shown in FIG.
It meshes with the teeth 18 and becomes a stopped state. The outer case 3a is connected to the inner case 31 via the drive member 17. In this way, when the outer case 3a is connected to the inner case 3b, the torque of the internal combustion engine is transmitted from the drive system such as the ring gear 2, the outer case 3a, and the drive pinion gear 1. member 17, inner case 3b,
Left wheel drive 1tq116a and right wheel drive shaft 6b from the first and second resistance plates 8, 9 and the first and second hubs 4.5, respectively
1 is transmitted, and the vehicle travels in four-wheel drive.

Next, when the front wheels slip while the vehicle is traveling on a road surface with a small coefficient of road friction 4, the rotation of the front wheel drive shaft becomes faster than the rotation of the rear wheel drive shafts 6a and 5b, which connects the inner case 31). The first resistance plate 8 that is connected to the left wheel drive shaft 6
A, J, and the second resistance plate 9 connected to the right wheel drive shaft 6b rotate relative to each other, shearing and covering the series 1 and A wheels. The shearing force of the silicone oil is transmitted as torque to the rear wheel drive shaft (3i1゜6b), and the rear wheels push the vehicle out of the slipping state.

515) i - One of the right rear wheels, for example, the right rear wheel, slips from the road surface (J means it does not slip) - the f side rear wheel receives a large amount of resistance. Therefore, a difference in rotational speed occurs between the first hub 4 and the in-boot case 3b, and the first resistance plate 8 and the second resistance plate 9 in the first air 11 rotate relative to each other. - Shear the 1-in A-il. Next, the shearing force of the silicone oil sheared by the first resistance plate 8 and the second resistance plate 9 reaches an upper limit and becomes intense, and furthermore, the gap 2 formed between the outer case 3a and the impingement goose 3b. ``1'' provides an insicolator effect and makes it difficult for heat radiation to occur, so that the hump phenomenon occurs quickly.

Therefore, the 1-luke of the internal combustion engine is directly transmitted from the inner case 3b to the left wheel drive shaft 5a, causing the slipping right wheel to escape from the left wheel, and the vehicle runs stably.

=11-Furthermore, when the steering wheel is turned sharply, such as when entering a garage, a difference in rotational speed occurs between the front wheel drive shaft and the rear wheel drive shaft. ,2
The relative rotation of the hubs 4 and 5 prevents the corner braking phenomenon from occurring.

This J: If, during two-wheel drive driving, the drive member 17 is moved to interrupt the connection between the outer case 3a and the inner case 3b, the outer case 3a1 ring gear 2,
The drive system from the drive pinion gear 1 to the lance front will not be driven from the opposite direction of the l~r flow. Therefore, the rotational resistance of this drive system is reduced,
In addition, stirring resistance of the lubricating oil flowing into the differential carrier 14 is not generated, and it is possible to further improve fuel efficiency and reduce wear. In addition, noise generated from the drive system can be reduced.

In addition, when driving in four-wheel drive, if the drive member 17 slides and connects the outer case 3a and the inner case 3b, when the front wheel slips, the vehicle is pushed by one wheel.
-1-t Shi, IIQ from the state where the front wheel is slipping
Bring it out. On the other hand, if one of the rear wheels on the right side slips, the other wheel will move the slipping wheel out by 1) and the vehicle will run stably. Further, when the vehicle is put into the garage, the inner case 3b and the first and second hubs 4, 55 rotate relative to each other, so that the tie 1-]-nerbraking phenomenon is prevented from occurring.

Therefore, by installing the four-wheel drive vehicle drive force transmission/disconnection device according to the present invention in a four-wheel drive vehicle, the functions of the conventional viscous coupling and the four-wheel drive vehicle drive force disconnection device can be improved. (You can hold it with a U.You can quickly take out the IB2 from muddy areas, or when you put it in the garage, etc., it absorbs the difference in rotation speed between the front and rear drive shafts. The corner braking phenomenon can be prevented from occurring, and running resistance, vibration, noise, etc. caused by the rotation of the driven side power transmission system can be reduced as much as possible during two-wheel drive.

By the way, the inner case 31] and the first and second hubs 4.5
Due to the relative rotation of the inner case 3b, the sealed silicone oil expands rapidly and the inner case 3b is damaged. Even if the silicone oil flows out from the inner case 3b, the outer case 3a is disposed outside the inner case 3b. Since the silicone oil does not suddenly leak into the differential carrier, it is possible to prevent the bearing B from burning out.

[Effects of the Invention] As explained above, according to the present invention, it is possible to combine the functions of a conventional viscous coupling and a four-wheel drive vehicle drive disconnection device. It is possible to quickly escape from mud, and when parking in a garage, etc., it can absorb the difference in rotation speed that occurs between the front wheel drive shaft and the rear wheel drive shaft, and prevent the occurrence of tight corner bragging phenomenon. In both cases, the two-wheel drive system can reduce as much as possible the deterioration of fuel efficiency, running resistance, vibration, noise, etc. caused by the rotation of the driven side dynamic horn transmission system.

[Brief explanation of the drawing]

1 and 2 are diagrams showing an embodiment of a driving force transmission/disconnection device for a four-wheel drive vehicle according to the present invention, and FIG. 1 shows this driving force transmission/! FIG. 2 is a sectional view showing a state in which the casing of the II connection device and the third rotating member are not connected, and FIG. 2 shows a state in which the casing of the driving force transmission/disconnection device and the third rotating member are connected. FIG. 3a...Casing 3b...Third rotating member 4...
- First rotating member 5... Second rotating member 7... Working chamber 8... First resistance plate 9... Second resistance plate 17... Drive section I 18.1
9...Engagement part (t#)

Claims (1)

[Claims] A first rotating member and a second rotating member arranged on the same axis, a third rotating member arranged so as to be relatively rotatable with the first rotating member and the second rotating member, and the third rotating member a working chamber defined by a first rotating member and a second rotating member and filled with a viscous fluid; A first resistance plate and a second resistance plate combined,
A four-wheel drive characterized by comprising a casing that is rotatably provided relative to the third rotating member and to which torque is transmitted, and a drive member that is provided so that the casing and the third rotating member can be moved into and out of contact with each other. Vehicle drive power transmission/intermittent device.