JPH02266122A - Magnetic clutch - Google Patents

Abstract

PURPOSE:To transmit a large clamping force to a multiple disk (friction) clutch speedily by installing an electromagnet supporting a yoke free of movement and a clamping member clamping the friction clutch as well as an adjusting means, moving the yoke, and adjusting an air gap between the clamping member and the electromagnet. CONSTITUTION:A differential case 17 is rotated by rotation and drive of an engine and a rear axle 11 is rotated through a pinion shaft 29, a pinion gear 33 and a side gear 37. A pair of clutch plate sets consisting of clutch plates 43, 45 are installed between this side gear 37 and the differential case 17, forming a multiple disk clutch 47. A yoke 59 of an electromagnet 57 is shiftably supported in the axial direction and rotated by a motor 47 via a worm 71 as in an arrow, forming an adjusting means. A clamping member 77 consists of a sleeve 79 and a flange 81. Since an air gap between an electromagnet and a clamping means is kept in an optimum value by this adjusting means, a large clamping force is speedily transmitted to a multiple disk (friction) clutch. Therefore the electromagnet is also enough to be small in size.

Description

DETAILED DESCRIPTION OF THE INVENTION [Objective of the Invention 1 <Field of Industrial Application] The present invention relates to an electromagnetic clutch device used for limiting the differential of a differential gear.

(Prior Art) Japanese Unexamined Patent Application Publication No. 1954-1988 describes a ``slip-limiting differential gear assembly J (power transmission device)'', and this differential gear assembly is equipped with an electromagnetic clutch.

j shown in FIG.
, the electromagnet 205 and the clutch 203 due to its attractive force.
The clutch 203 is configured to include a fastening member 207 for fastening the clutch 203, and the differential movement of the differential device 201 is limited by the fastening force of the clutch 203. The air gap 209 between the electromagnet 205 and the fastening part IJ 207 is adjusted in advance by a shim 211 at the time of set (=1).

In this way, although it is possible to adjust the air gap 209, it is difficult to cope with changes in the air gear 11 knob 209 due to wear of the clutch 203. Therefore, when adjusting the shims, the air gap 209 must be set wide enough to allow for wear.

When the air gap 209 is wide, the suction force of the fastening member 207 is weak, and as shown in the graph of FIG. 4, the pressing force decreases rapidly. become

(Problems to be Solved by the Invention) Therefore, an object of the present invention is to provide an electromagnetic clutch that can always optimally adjust the air gap between the electromagnet and the fastening member, and can therefore be miniaturized.

[Structure of the Invention] (a! Means for Solving Problem) The dynamic horn transmission device of the present invention includes an electromagnet that movably supports a yoke, and a fastening member that fastens a friction clutch by the electromagnetic force of the electromagnet. The electromagnetic clutch is characterized in that it includes an adjusting means for adjusting the air gap between the yoke and the fastening member by moving the yoke.

(Function) The air gap between the yoke of the electromagnet and the V1 fastening member can be adjusted by moving the yoke of the electromagnet by the adjusting means.

(Example) An example will be described with reference to FIGS. 1 to 5. FIG. 5 shows a vehicle using this embodiment. Hereinafter, the left and right directions refer to the left and right directions of Figures 1 and 5, and the upper part of Figure 1 is the 5th direction.
The front of the vehicle in the figure (corresponds to the upper part of Figure 5).

First, the configuration will be explained.

The power system of the vehicle shown in Figure 5 is engine 1, Heheras mission 3, propeller shaft 7, and rear wheel differential arrangement 1.
The power transmission device 9 of this embodiment used as a rear axle i1. ii Left and right rear wheels 13°13, left and right front wheels 15
．． It consists of 15 etc.

The differential case 17 is rotatably supported by a differential carrier 21 by bearings 19 and the like. A ring gear 23 shown in FIG. 5 is fixed to the differential case 17.
It meshes with 727. In this way, differential case 1
7 is rotationally driven by the driving force from the engine 1.

A binion shaft 29 is supported by the differential case 17. The pinion shaft 29 is arranged radially around the hollow boss 31, and a pinion A gear 1733 is rotatably supported on the pinion shaft 29. A pair of side gears 35 and 37 mesh with the side gear 33 from the left and right.

In this way, the differential device 39 is configured.

A washer 40.40 is arranged between each side gear 35.39 and the boss 31. Each side gear 35.37
The left and right rear axles 11.degree. 11 are connected by splines, respectively, and a snap ring 41 is attached to each spline portion to restrict mutual axial movement.

Therefore, the rotation of the γ case 17 is controlled by the pinion shaft 29.
, is differentially distributed from the pinion gear 33 to the left and right rear axles 11, 11 via the side gears 35 and 37 due to the rotation of the pinion gear 33.

A plurality of clutch plates 43, 45 are arranged alternately between the outer periphery of the right side gear 37 and the inner periphery of the differential case 17.
A pair of clutch plate sets consisting of the above are separately engaged with the side gear 37 and the differential case 17 by splines, thereby forming a multi-plate clutch 47 (friction clutch). Multi-plate clutch 4
7 is pressed and fastened between a pressure receiving member 49 fixed to the differential case 17 side and a suppression ring 51 splined to the right vehicle lll1l111 so as to be movable in the axial direction. A washer 53 is arranged between the side gear 37 and the pressure receiving member 49. When the multi-disc clutch/1.7 is engaged, the rotation of the pinion gear 33 is restricted by limiting the differential between the differential case 17 and the side gear 37 according to the engagement force, and the differential between the rear wheels 13 and 13 is restricted. limited.

On the right end side of the differential carrier 21, a yoke 59 of an electromagnet 57 is rotatably driven by a threaded portion 55 provided between the differential carrier 21 and supported so as to be movable in the axial direction. A feeding portion 67 is provided in which the lead wire 65 of the coil 63 is fed out by the tension caused by the rotation of the yoke 59. A worm wheel 69 is formed on the outer periphery of the yoke 59, and a worm 71 is meshed with the worm wheel 69.

The worm 71 is reversibly rotationally driven by a DC motor 73 fixed to the differential carrier 21, rotates the yoke 59 via the arm 71, and moves it left and right as shown by the arrow. In this way, the adjusting means 75 is configured.

Fastening part + J 77 i, t sleeve 79 and flange 81
It consists of The sleeve 79 is fitted between the outer periphery of the right axle 11 and the inner periphery of the yoke 59 of the electromagnet 57, and the sleeve 79 is fitted between the outer periphery of the right axle 11 and the inner periphery of the yoke 59 of the electromagnet 57.
3, it passes through the differential case 17 and is rotatably and axially movably supported, and its left end is connected to a suppression ring 51.
I'm facing away from it. A preload spring 87 is provided between the fastening member 77 and the large diameter side surface 85 of the axle 11 to press the fastening member 77 to the left and prevent the multi-disc clutch/1.7 from being fastened with a certain amount of force via the suppression ring 51. is installed. Therefore,
As the multi-disc clutch 47 wears, the fastening member 77 moves to the left by the biasing force of the preload spring 87 by the wear amount. The flange 81 is arranged on the right side of the yoke 59, and an air socket 89 is formed between them. In this way, the electromagnetic clutch 91 is configured.

A seal 9 is provided between the fastener 21 and the fastening member 77.
3, an O-ring 95 is placed between the fastening member 77 and the car #J11, and protects the electromagnet 57, air grip 89, etc. from oil from inside the differential case 17 and wear powder from the multi-disc clutch 47. Isolated and protected. A seal 97 is arranged between the axle 11 and the differential gear rear 21, and several covers 99 are provided on the differential case 21.

The electromagnetic clutch 91 is manually operated from the driver's seat or automatically operated according to steering conditions, road surface conditions, etc. to perform the above-mentioned differential restriction.

By loosening the fastening force of the electromagnetic clutch 91, the differential between the rear wheels 13 and 13 becomes free, allowing the vehicle to turn smoothly. Also, when one of the rear wheels 13.13 slips on a rough road, if a large engagement force is applied to the electromagnetic clutch 91, the differential between the rear wheels 13.13 is stopped, and the engine is also applied to the other rear wheel 13. Since one driving force is sent, smooth running can be maintained.

The adjusting means 75 adjusts the air gap 89 by means of a =1 controller (not shown) in an adjustment program such as flow ↑.-1 in FIG.

Next, the adjustment program will be explained according to this flowchart. B: While the vehicle is running, the fastening member 77 is attracted and the eight air gaps change, so this adjustment is performed while the vehicle is stopped.

]-When engine 1 is started, the adjustment program starts. In step S1, a handbrake signal is read, and in slip S2, the vehicle speed is read.

In the slurry block S3, it is determined whether or not the vehicle is stopped based on the entry data obtained in steps Sl and S2.

If the Zide brake is in operation or the vehicle speed is not zero (i'J), it is determined that the vehicle is running (NO), and the program is terminated without adjusting the air gap. Vehicle stopped J1. :
(Y F S ) If so, step S4 is performed.

In Slurtub S4, the DC motor 73 receives a forward rotation signal of 111.
Powered. In addition, 1] When the C7-tor 73 rotates in the normal direction, is it electromagnetic?
i57]-ri 59 moves toward the right flange 81. In step S5, the current value TM of the DC motor 73 is read.

In step S6, it is determined whether the current value IM has reached the set value of 0.5A shown in the graph of FIG. Here, whether or not the air gap 89 has become zero is determined by detecting the upper arm of the current value IM caused by the abutment between the yoke 59 and the flange 81. ! J, if lu is less than the set value (No), the air gap 89 is not zero, so step S5
This loop is repeated until IM reaches the set value.
Airgill? When the knob 89 becomes zero and IM rises to the set value (YES), the process moves to step S7 b-4.

J--that is, the graph of FIG.
, S6 proceeds to the right as indicated by arrow 101 until IM reaches the set value.

At step $7, a reverse rotation signal is output to the DC motor 73, the five yokes move to the left, and the air cap 89 expands.

In step $8, it is determined whether a set time has elapsed since the start of the signal output from the block S7.However, what is this set time? 73, and the optimum value S is the multi-disc clutch 47 as shown in the graph of FIG.
This is the amount of air gap that provides a large pressure point. This step is repeated until the set time has elapsed (if NO>, then YES if the set time has elapsed), and when the air gap 89 reaches S, the process moves to step S9.

In step S9, the output to the DC motor 73 is stopped, rotation is stopped, and the air gap 89 is maintained at S. After that, the program will end. That is, step 8
7.88.89 is the air gap 89 on the graph of Figure 3.
The vehicle advances to the left as indicated by an arrow 103 until becomes S.

As mentioned above, as the multi-disc clutch 47 wears, the flange 81 moves to the left by the preload spring 87 to constantly absorb the play caused by the wear, and the above adjustment is performed every time the engine 1 is started. Therefore, the air gap 8 is always kept at the optimum value S, and as shown in FIG. 4, a large pressing force on the multi-disc clutch 47 can be quickly obtained. Therefore, unlike the conventional device, which requires a wide air gap to be set, and which requires a large device to compensate for the sudden drop in pressing force, the electromagnetic clutch 91 can be made smaller, and the device 9 can be made smaller and lighter accordingly.

Further, since the electromagnet 57 is arranged outside the differential carrier 21, a cooling effect by the outside air is obtained, and the influence of heat from the inside of the differential case 17, particularly from the multi-disc clutch 47, is reduced. Therefore,
The performance of the electromagnet 57 does not deteriorate due to temperature rise. or,
Since the electromagnet 57 is isolated from the inside of the differential carrier A721 by the seal 93 and the O-ring 95, the air gap 89 will not be clogged with oil or wear particles of the multi-disc clutch 47, which will prevent performance deterioration of the electromagnet 57 and the multi-disc clutch of the fastening member 77. 47
No pressing defects will occur.

Note that the adjusting means is, for example, the electromagnet 57 in the above embodiment.
is engaged with the differential carrier 21 so as to be movable in the axial direction, and the worm wheel 69 is turned into a pinion, and the A-worm wheel 71 is turned into a pinion and reversibly rotated by a DC motor to move the electromagnet 57 and adjust the air gap 89. Alternatively, a DC motor may be used as the adjusting means, and a screw or the like protruding from the outside may be provided so as to be manually operable.

Also, this invention has a differential arrangement for the electromagnetic clutch↑! The input torque is not configured as a differential limiting device for the differential control device.
The information may be configured to be transmitted to the Rental device.

[Effects of the Invention] As described above, according to the present invention, it is possible to always maintain the air gap between the electromagnet and the fastening member at an optimum value, and it is possible to quickly apply a large fastening force to the friction clutch. Therefore, the electromagnetic clutch can be made smaller and the device can be made smaller and lighter.

[Brief explanation of drawings]

Fig. 1 is a sectional view of one embodiment, Fig. 2 is a flowchart of the air gap adjustment program, Fig. 3 is a graph showing the relationship between the air gap and motor current, and Fig. 4 is a graph showing the relationship between the air gap and motor current. A graph showing the relationship with pressure; FIG. 5 is a skeleton mechanism diagram showing the power system of a vehicle using the embodiment shown in FIG. 1;
FIG. 6 is a sectional view of a conventional example. 47... Multi-plate clutch 57... Electromagnet 75... Adjusting means 89... Air gap (friction clutch) 59... Yoke 77... Fastening member 91... Electromagnetic clutch

Claims (1)

[Claims] An electromagnetic clutch having an electromagnet movably supporting a yoke and a fastening member that fastens a friction clutch by the electromagnetic force of the electromagnet, comprising an adjusting means for moving the yoke to adjust an air gap with the fastening member. Features an electromagnetic clutch.