JPH0314919A - Visous coupling - Google Patents

Abstract

PURPOSE:To improve response of characteristic control by providing an operation chamber in which visous fluid is sealed, a pair of resistance members which have opposing portions in the operation chamber, transmission members in which one of engagement parts with the resistance member is capable of being engaged on disengaged, and the engagement means. CONSTITUTION:A housing 31 and a transmission shaft 33 are rotatably and coaxially arranged as transmission members, while an operation chamber 35 in which viscous fluid is sealed is formed therebetween. A pair of clutch cylinders 41, 43(resistance members) are alternately arranged inside the operation chamber 35, and a coupling member 49 is slidably arranged on an inner periphery of the housing 31. An engagement part 53 is formed on a flange 47 of the clutch cylinder 43. When the coupling member 39 is slid leftward, it is engaged with the engagement part further deeply, and when it is slid rightward, the engagement rate is decreased. The differential controlling force and transmission torque are increased with the deeper engagement, while they are decreased with the slighter engagement. The moving distance of the coupling member 49 is only a thickness L of the clutch cylinder 43, so that response of characteristic control is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a viscous coupling that transmits torque through a viscous fluid.

<Prior Art> A viscous clutch (viscous coupling) is described in JP-A-62-106130G.

As shown in FIG. 4, this device has a structure f7 formed between a housing 101 and a sleeve 103 and containing a viscous fluid.
Cylinders 107 alternately arranged in the radial direction inside one chamber 105
．． 109 is engaged with the members 101 and 103 separately,
The structure is such that the overlapping margin L between the cylinders 107 and 109 can be adjusted by the moving means 111 to control the torque transmission characteristics.

However, in this configuration where the overlap margin L is changed, a large movement stroke is required and the response of characteristic control is poor.Furthermore, the volume of the working chamber must be increased by the space corresponding to the movement stroke, which reduces the transmission torque. The monks are relatively large.

(Problems to be Solved by the Invention) Therefore, an object of the present invention is to provide a viscous coupling that has good response in characteristic control and can be downsized.

[Structure of the Invention] (Means for Solving the Problems) The viscous coupling of the present invention includes a working chamber filled with a viscous fluid, a pair of resistance members arranged alternately and having opposing parts in the working chamber, and a relative rotation. A pair of transmitting members which are freely arranged and have separate engagement parts with the resistance members, at least one of which can be engaged and detached, and an engagement and disengagement means for engaging and disengaging the transmission members. Features.

(Operation) Torque input from one of the transmission members is transmitted from one resistance member to the other resistance member by the shear resistance of the viscous fluid, causing the other transmission member to rotate.

At this time, if the rotational difference (differential) between input and output is large, this rotational difference is limited to υ1 and a large torque is transmitted, and if the rotational difference is small, this rotational difference is allowed and the transmitted torque becomes small.

The transmission member and the resistance member are engaged and disengaged by the engagement and disengagement means, and if the number of engaged resistance members is increased, the differential limiting force and the transmitted torque will increase, and if the number of engagement members is decreased, the differential limiting force and the transmitted torque will be increased. decreases.

(Embodiment) The first embodiment will be explained with reference to Figs. 1 and 2. This embodiment is used in the power system of the vehicle shown in Fig. 2.
The left and right direction is the left and right direction in Figure 1, and the left side is the second direction.
This corresponds to the front of the vehicle in the figure (upper part in Figure 2).

First, the configuration will be explained.

The power system of the vehicle shown in Fig. 2 includes an engine 1, a transmission 3, a transfer 5, a differential device 7 on the front wheel side, @car @9.11, left and right #J widths 13 and 15, a viscous coupling 17 in this example, Blowera shaft 1
9. Rear wheel side differential device 21, rear single shaft 23.
25, left and right rear wheels 27.2.9, etc.

The housing 31 (transmission member) and the transmission shaft 33 (transmission member) of the viscous coupling 17 are coaxially arranged so as to be relatively rotatable, and a working chamber 35 is formed between them, in which high-viscosity silicone oil is sealed. Housing 3
1, X rings 37.37 (I!Fi is an X-shaped sealing material) and backup rings 39.39 are installed between the transmission shaft 33 on the left and right sides of the operation chamber 35, and the operation chamber 35 is It is kept secret.

Inside the working chamber 35, a pair of cylindrical crud tubes 41.
43 (resistance members) are arranged alternately in the radial direction. The left clutch cylinder 41 is fixed to a flange portion 45 provided on the transmission shaft 33. Further, seven flange portions 47 are provided at the right end portions of the right clutch cylinders 43, respectively.

A connecting member 49 is disposed on the inner circumference of the housing 31 in the axial direction ll! as indicated by an arrow 51! IvJ is freely spline connected. 7 langes 4 of this connecting member 49 and clutch cylinder 43
7 is provided with a spline portion 53 (a removable engagement portion) that can be engaged and disengaged in the axial direction, and when the connecting member 49 slides leftward on the housing 31, it engages with the clutch cylinder 43. The number of clutch cylinders 43 that are engaged increases according to the stroke. Furthermore, sliding to the right releases these locks. For example, in FIG. 1(b), the two inner clutch tubes 43a are in a disengaged state, and the three outer clutch tubes 43b are in an engaged state and rotate together with the four connecting members. Therefore, when the transmission shaft 33 rotates due to the driving force from the engine 1, this rotation is transferred from the clutch cylinder 41 to the clutch cylinder 4 due to the shear resistance of the silicone oil.
3, the housing 31 is rotated through four connecting members, and the rear wheel 27.29 is rotationally driven. This moment,
If the rotation difference between the input and output is large, this rotation difference is limited to II1 and a large torque is transmitted, and if the rotation difference is small, this rotation difference is allowed and the transmitted torque becomes small. Also, the connecting member 49
As the number of clutch cylinders 43 that engage increases, the differential limiting force and transmission torque increase, and as the number of engagements (2) decreases, the differential limiting force and transmission torque decrease, and all the clutch cylinders 43 engage. When the connection is released, torque transmission is cut off.

The left end portion of a rod 55, which passes freely through the housing 31 in a fluid-tight manner, is fixed to the four connecting members. Rod 5
The right end of 5 is fixed to a ring 57, and the ring 57
is axially connected to the operating ring 61 via a bearing 59. When the operating ring 61 is moved in the axial direction as indicated by the arrow 62, the connecting member 49 is moved left and right via the bearing 59 and the rod 55 to engage and disengage from the clutch cylinder 43. The moving distance of the four connecting members at this time is the sum of the thicknesses of the housing portion 47 of the clutch cylinder 43, as shown in FIG. 1(b). In this way, the engaging/disengaging means 6
3 are made up. 7 langes 47 of clutch cylinder 43
Stoppers 6 are provided between the housing 31 and the left and right sides of the housing 31, respectively.
5.67 is arranged to restrict the left and right movement of the clutch cylinder 43 during engagement and disengagement. In addition, a rod 5 is installed in the working chamber 35.
Six 7-cumulators are provided to absorb the change in volume due to the inflow and outflow of the 7-cumulators.

Such an operation of the engaging/disengaging means 63 can be performed manually from the driver's seat or automatically according to steering conditions and road surface conditions.

Next, the functions will be explained based on the performance of the vehicle shown in FIG. When the rotation difference between the front and rear wheels is small, such as when driving on a good road, the driving force transmitted to the rear wheels 27 and 29 via the viscous coupling 17 is small, so the vehicle is essentially a two-wheel front-wheel drive vehicle. This is a characteristic of the driving vehicle and improves fuel efficiency compared to a four-wheel drive state. At this time, this tendency can be promoted by operating the engagement/disengagement means 63 to reduce the number of engagement cylinders 43, and if the number of engagement cylinders 43 is reduced to zero, the driving force transmission is interrupted and the rear wheel 27.29 side is in a free rotation state.

Furthermore, the straight-line stability is improved by the differential limiting force between the rear wheels by the viscous coupling 17. If the number of engaged clutch cylinders 43 is increased, the differential limiting force will increase and the straight-line stability will be further improved.

When the front wheels 13.15 slip on rough roads and the difference in rotation between the front and rear wheels increases, the viscous coupling 17
Since a large driving force is sent to the rear wheels 27, 29 via the rear wheels 27 and 29, the vehicle can maintain smooth running without getting stuck, and its running performance is improved. At this time, the clutch cylinder 4
If the number of 3 is increased, the driving force transmitted to the rear wheel side will be increased, and the running performance will be further improved.

When making a sharp turn at low speed, such as when parking the vehicle, the small rotational difference between the front and rear wheels is absorbed by the viscous coupling 17, thereby preventing tight corner braking.

As described above, the moving distance of the connecting member 49 when engaging and disengaging from the clutch cylinder 43 is the sum of the thicknesses of the clutch cylinder 43, which is very short compared to the movement stroke of the conventional example in which the cylinder is moved. Therefore, the response of the characteristic II1H is extremely good, and the necessary characteristic control as described above can be performed when necessary without missing the timing. Furthermore, unlike the conventional example, there is no need for a large space for moving the cylinder, so not only the working chamber 35 but also the entire device can be downsized.

Next, the second embodiment will be explained with reference to FIG.

This viscous coupling 71 is also used in the same location as in the first embodiment in the vehicle shown in FIG.

Hereinafter, the differences from the first embodiment will be mainly explained while referring to the same members with the same numbers.

A comb-shaped protrusion 75 is provided at the right end of the right clutch cylinder 73, and as shown in FIG. 2(b), the height of this protrusion 75 is lower as the inner clutch cylinder 73 is. The connecting member 77 is spline connected to the inner periphery of the seven housings so as to be movable in the axial direction, and a plurality of rod portions 81 formed in the circumferential direction slidably penetrate the housing 79 in a liquid-tight manner, and the right end thereof is fixed to the ring 57. In this way, the engaging/disengaging means 83 is configured, and the connecting member 77 is operated to move left and right as shown by the arrow 85 by the operating force from the operating ring 61. The clutch cylinder 7 is located at the left end of the connecting member 77.
Four comb-shaped portions 87 are provided that constitute engaging portions that can be engaged with and detached from the convex portions 75 of No. 3.

When the connecting member 77 moves to the left, the clutch cylinder 73 is engaged from the outside to the inside, and the number of engaged parts increases, increasing the differential limiting force and the transmitted torque, and when the connecting member 77 moves to the right, the clutch cylinder 73 is engaged from the inside to The clutch cylinder 73 is disengaged, the number of clutch cylinders 73 engaged is reduced, and the differential limiting force and transmitted torque are reduced. When the number of engaged wheels becomes zero, the transmission of driving force to the rear wheels 27 and 29 is interrupted.

Further, the moving distance of the connecting member 77 is the distance M1- between the engaging portions of the outermost and innermost clutch cylinders 73, which is very short. Therefore, the response of characteristic control is good. For the same reason, there is no need to provide the actuator 189 with a large moving space, so the entire device can be constructed in a compact size.

Other configurations, functions, effects, etc. are the same as those in the first embodiment.

[Effects of the Invention] As described above, the viscous coupling of the present invention has good response in characteristic control and can be miniaturized.

[Brief explanation of the drawing]

FIG. 1(a) is a partial sectional view of the first embodiment, and FIG. 1(b) is (
Figure 2 is a skeleton mechanism diagram showing the power system of the vehicle using the embodiment, Figure 3 (a) is a partial sectional view of the second embodiment, and (b) is the ), and FIG. 4 is a sectional view of a conventional example. 31.79... Housing (transmission part first) 33... Transmission shaft (transmission member) 35.89... Operation flJ chamber 41, 43.73... Clutch tube (resistance member) 63.
83...Mounting/disengaging means 2 Figure

Claims (1)

[Claims] A working chamber containing a viscous fluid, a pair of resistance members arranged alternately and having opposing parts in the working chamber, and separate engaging parts with these resistance members arranged so as to be relatively rotatable, each of which A viscous coupling comprising a pair of transmission members, at least one of which can be engaged and detached, and a means for engaging and disengaging.