JPH0356720A - Hydraulic power transmission coupling - Google Patents

Abstract

PURPOSE:To improve durability and accuracy of control by keeping a moving magnetic substance installed on a rotating member on one side a magnetic frame and a solenoid both fixed on a non-rotating member in a non-contact condition, and constituting an electromagnetic actuator as a whole unit to operate a controlling means directly. CONSTITUTION:Working fluid discharged from a plunger chamber 16 is dis charged to a main passage 27 and a valve means 38 is installed in order to control flow resistance of that fluid. A moving magnetic substance 40 is formed integratedly at the edge of the valve means 38 and sealed in a rotor 1 covered with a non-magnetic tubular body 39. A magnetic frame 43 fixed on a casting 3 is kept in a non-contact condition with the tubular body 39 and accommodates a solenoid 44 inside. The moving magnetic substance 40, the magnetic frame 43 and a solenoid coil 44 constitute a solenoid as a whole unit to control the valve means 38. As the magnetic frame 43 and the solenoid coil 44 are fixed on the casing 3 oil leakage is prevented and, as the magnetic substance 43 is in a non-contact condition with the tubular body 39 wear is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a hydraulic power transmission joint used for distributing driving force in a vehicle.

[Prior Art] An example of a conventional vane-bump type hydraulic power transmission joint that is externally controlled is disclosed in Japanese Patent Laid-Open No. 61-249827.

In addition, as a conventional plunger pump type hydraulic power transmission joint that is externally controlled, for example, Japanese Patent Laid-Open No. 63-1
There is one disclosed in No. 01567.

There are two structural types of these control actuators as follows.

The first type has a solenoid valve on a fixed part that does not rotate, and controls the joint by supplying hydraulic pressure controlled by the solenoid valve to the interior of the joint through a rotary shaft seal.

In the second type, a solenoid valve is provided on a rotating joint, power is supplied from a fixed part to the solenoid valve through a slip ring, and the joint is controlled by the solenoid valve.

[Problem to be solved by the invention]However, in the case of the actuator that externally controls such a conventional hydraulic power transmission joint, in the former case, there is a lot of oil leakage from the rotating shaft seal, and the control accuracy deteriorates. In addition to this, there was a problem in that durability was reduced due to wear of the rotary shaft seal. In addition, since a hydraulic pressure source for control is required, there is also the problem that the cost increases.

In the latter case, there is a problem that when the joint rotates at high speeds, the brushes dance, causing the power supply to be cut off and control to be impossible.Moreover, maintenance is required to prevent wear of the brushes and slip rings, which increases costs. The problem was that it was expensive.

The present invention has been made in view of such conventional problems, and provides a hydraulic power transmission joint that can improve durability at low cost and improve control accuracy. The purpose is to

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a hydraulic pump driven by a rotational speed difference between a t-th and a second rotating member that are relatively rotatable; The discharge path of the pump is provided with a control means for generating flow resistance according to an external control signal, and the first. In a hydraulic power transmission joint in which the transmission torque between the second co-rotating members is controlled, a movable magnetic body is housed in the center of the one rotary member so as to be movable in the axial direction, and a third member that does not rotate. The fixed magnetic frame and the solenoid coil are held in a non-contact state to constitute an electromagnetic actuator as a whole, and the actuator directly operates the flow resistance control means.

[Function] In the present invention, a movable magnetic body is housed in the center of the one rotating member so as to be movable in the axial direction, and a third magnetic body that does not rotate.
The magnetic frame fixed to the member and the solenoid coil are held in a non-contact state, and the whole constitutes an electromagnetic actuator, and the actuator directly operates the flow resistance control means, thereby controlling the rotation shaft seal. It is possible to eliminate deterioration in control accuracy due to oil leakage and decrease in durability due to abrasion of the rotary shaft seal, which were problems in the conventional case.

Furthermore, it is possible to eliminate the problem of interruptions in power supply due to dancing of the brush at high speeds and wear of the brush and slip ring, which were problems when power was supplied to a rotating solenoid using a slip ring.

[Example] Embodiments of the present invention will be described below based on the drawings.

1 to 3 are diagrams showing a first embodiment of the present invention,
This applies to a four-wheel drive vehicle based on a rear-wheel drive vehicle.

First, to explain the configuration, in Fig. 1, 1 is the front drive shaft (first rotating member) which is the output shaft (
A rotor 1 is rotatably supported by casings 2 and 3 via bearings 4 and 5.

A drip sprocket 7 is rotatably supported on the rotor 1 via a twenty dollar bearing 6, and a chain 9 is installed between the drip sprocket 7 and the drive sprocket 8. In addition, 10 is an output flange, 1{ is a nut, 12.13 is an oil seal, 14 is a stop ring, and 15 is a thrust washer.

A plurality of plunger chambers 16 are formed in the rotor (2) in the axial direction, and a plurality of plungers 17 that reciprocate in the axial direction are housed in the plunger chamber 16. A cam surface 18A is formed on the inner surface of a cam housing (second rotating member) 18 fixed to the driven sprocket 7, and the plunger 17 is in sliding contact with the cam surface 18A. Note that the plunger 17 and the plunger chamber 16 collectively constitute a hydraulic pump.

19 is a suction passage communicating with the plunger chamber 16, and a suction valve 20 is interposed in the suction passage 19. That is,
The suction valve 20 is provided coaxially with the plunger chamber 16 and at the bottom. A return spring 21 holds the suction valve 20, and a plug 22 holding the return spring 21 is held by the return spring 23 of the plunger 17.

Reference numeral 24 denotes a discharge passage that opens in the side wall of the plunger chamber 16 and is formed toward the center of the mouthpiece 1. A discharge valve 25 is interposed in the discharge passage 24 via a return spring 26.

The working fluid discharged from these plural plunger chambers 16 passes through one outlet hole 28 and is discharged to the main passage 27 side, and a high pressure chamber (collection chamber) 29 is defined by the discharge valve 25 and the outlet hole 28. has been completed.

Further, a valve means 3 is provided on the main passage 27 side of the outlet hole 28 for controlling the flow resistance by controlling the opening area of the outlet hole 28.
8 is provided.

Further, the main passage 27 communicates with the suction passage 19 via a passage 30 formed in the rotor 1.

Further, 31 is a plug that holds the return spring 26, 32 is a piston, and 33 is a spring that holds the piston 32. Also, 34.35 is an oil seal,
36 is a stop ring, and 37 is a thrust washer.

Here, the valve means 38 has a movable magnetic body 40 at its end.
is integrally formed, covered with a non-magnetic cylindrical body 39, and enclosed within the rotor 1.

A communication hole 41 is formed in the movable magnetic body 40, and the movable magnetic body 40 is biased by a return spring 42 having a weak force.

A magnetic frame 43 is fixed to the casing 3 and forms a magnetic circuit. The magnetic frame 43 is held in a non-contact state by the non-magnetic cylinder 39 inside the rear end of the movable magnetic body 40, and has a solenoid coil inside. It stores 44.

The movable magnetic body 40, the magnetic frame 43, the solenoid coil 4
4 constitutes a solenoid as a whole, and controls the valve means 38 by electromagnetic force.

Note that 46 is a cover provided on the magnetic frame 43.

Next, FIG. 2 shows the arrangement of the joints.

In FIG. 2, 51 is an engine, 52 is a transmission, and 53 is a transfer.

A main shaft 54 is rotatably supported within the transfer 53 by the casings 2 and 3 via bearings 55 and 56, and the main shaft 54 is provided with a drive sprocket 8. A drip sprocket 7 connected to a drive sprocket 8 by a chain 9 is rotatably supported by the rotor 1 via a needle bearing 6. The port 1 incorporates the aforementioned joint 57.

In addition, 58 is the right front wheel, 59 is the left front wheel, 60 is the right rear wheel, 6
1 is the left rear wheel, 62 is the front wheel side differential gear device,
63 is a rear wheel side differential gear device, 64 is a front wheel side propeller shaft, and 65 is a rear wheel side propeller shaft.

Next, the effect will be explained.

When a rotation difference occurs between the cam housing 18, which rotates integrally with the driven sprocket 7, and the rotor 1, the plunger 17, which is in the discharge stroke, is pushed in the axial direction by the cam surface 18A, and the fluid in the plunger chamber 16 is discharged. It is pushed out to the high pressure chamber 29 via the valve 25.

The hydraulic fluid collected in the high pressure chamber 29 pushes away the valve means 38 and is discharged from the outlet hole 28 to the main passage 27 side.

In this case, the stronger the force acting on the valve means 38, the more
The hydraulic pressure that displaces the valve 8 also increases, and since this hydraulic pressure is basically unrelated to the discharge flow rate, by controlling the force acting on the valve means 38, the transmitted torque t is controlled regardless of the differential rotation speed of the joint 57. can do.

That is, by controlling the value of the current flowing through the solenoid coil 44, the transmission torque t of the joint 57 can be controlled.

Here, the return spring 42 presses the valve means 38 with a slight load, thereby eliminating play in the valve means 38 and improving control responsiveness.

Further, a dither signal is added to the current flowing through the solenoid coil 44 to stabilize control.

In this embodiment, the movable magnetic body 40 is replaced with a non-magnetic cylindrical body 3.
9 and integrally formed with the movable magnetic body.
8 is sealed inside the rotor 1, and the magnetic frame 43 and solenoid coil 44 are fixed to the casing 3 so that they do not rotate. It is possible to prevent power supply failures due to brush movement.

Further, since the magnetic frame 43 housing the solenoid coil 44 is held in a non-contact state with the non-magnetic cylinder 39, wear due to contact can be prevented.

Therefore, durability can be improved, and control accuracy can also be improved.

Next, FIGS. 4 and 5 are diagrams showing a second embodiment of the present invention.

In FIG. 4, reference numeral 71 denotes an orifice valve having an orifice 72, which is provided between the high pressure chamber 29 and the main passage 27 via a return spring 73. 74 is a holding member that holds the return spring 73.

On the right side of the orifice valve 71, a valve means 38 is pushed by a return spring 42 and stopped at the position shown in FIG. 4, and in combination with the orifice valve 71 forms a variable orifice mechanism.

A movable magnetic body 40 is fixed to the right end of the valve means 38, and is held in a non-contact state with a magnetic frame 43 fixed to a non-rotating third member (case) 3 and a solenoid coil 44, so that the entire structure is It constitutes a solenoid.

Further, an oil seal 75 is provided at the right end of the rotor 1 to prevent oil leakage from the valve means 38.

Next, the operation when the solenoid is off will be explained.

As shown in FIG. 5, the orifice valve 71 does not move until the discharge pressure of the high pressure chamber 29 reaches t1, and the orifice 72 provides the normal characteristics indicated by A.

When the discharge pressure t of the high pressure chamber 29 exceeds t1, the orifice valve 71 moves and the orifice 72 is closed by the valve means 38, resulting in a locked state (see B). Furthermore, the discharge pressure t of the high pressure chamber 29 increases to t2. When reaching the valve means 3
8 moves to the right against the return spring 42. Therefore, as shown by C in FIG. 5, a relief characteristic is obtained, and the torque t can be limited.

Next, the operation when the solenoid is on will be explained.

When the solenoid is turned on, the valve means 38 moves to the right. Therefore, the orifice 72 is not closed by the valve means 38 and is therefore not locked as shown in FIG. 5D. In other words, it returns to its normal characteristics. Note that the valve means 38
Even if it is sucked by the solenoid and moves to the right, the step provided in the valve means 38 hits the stopper 76, so it will not move beyond a predetermined position, and the cover 46 will not rotate.
There will be no interference. This control is used to prevent hydraulic locking when it is better not to lock the joints, such as in tight corners. Note that other effects are the same as in the above embodiment.

Next, FIGS. 6 and 7 are diagrams showing a third embodiment of the present invention.

In FIG. 6, 81 is a 21 dollar valve movably housed in the housing hole 82 of the plug 31, and 83 is an orifice whose opening area is variable by the 21 dollar valve 81.

Further, the high pressure chamber 29 is provided with an outlet hole (relief hole) 84 separate from the variable orifice mechanism, and the valve means 38 biased by the return spring 42 closes this outlet hole to form a relief valve. ing.

A movable magnetic body 40 is fixed to the right end of the valve means 38, and is held in a non-contact state with a magnetic frame 43 fixed to a non-rotating third member (case) 3 and a solenoid coil 44, so that the entire structure is It constitutes a solenoid.

An oil seal 75 is provided at the right end of the rotor 1 to prevent oil leakage from the valve means 38.

Note that even if the valve means 38 is attracted by the solenoid and moves to the right, the step provided in the valve means 38 hits the stopper 76, so it will not move beyond a predetermined position, and the movable magnetic body 40 will not rotate. There is no interference with the frame 43.

First, the operation when the solenoid is off will be explained.

When the solenoid is off, the normal characteristics as shown in A are maintained until the discharge pressure t1 is reached, and when the discharge pressure t reaches t1, the orifice 83 is closed by the twenty-one dollar valve 81 and becomes locked (see B). ), when the discharge pressure t reaches t2, the valve means 38 forming the relief valve moves to the right against the return spring 42 and closes the relief hole 84.
and becomes a relief characteristic (see C).

Next, the operation when the solenoid is on will be explained.

When the solenoid is on, the movable magnetic body is attracted by the solenoid, so it moves to the right against the return spring 42 and opens the relief hole 84. Therefore, it becomes a free state as shown in E of FIG. This control is controlled to function when ABS is activated and when cornering. Note that other effects are the same as in the above embodiment.

Next, FIGS. 8 and 9 are diagrams showing a fourth embodiment of the present invention.

In FIG. 8, two solenoid coils 91 and 92 are housed in the magnetic frame 43, and a twenty-one dollar valve (
The rear end of the movable magnetic body 40 is located outside the solenoid coil 91 and inside the solenoid coil 92. Reference numeral 93 is a check ball for positioning the twenty-one dollar valve (movable magnetic body) 40 at a predetermined position when both the solenoid coils 91 and 92 are off, and the check ball 93 is held by a spring 94. 95 is an orifice having a predetermined opening area when the valve means 38 is not operated.

When both solenoid coils 91,92 are off, the valve means 38 is positioned by the check ball 93 and assumes its normal characteristic as determined by the orifice 95, as shown in FIG. 9A.

Next, when the solenoid coil 91 is on, the valve means 3
8 moves to the left in the figure to close the orifice 95.

Therefore, as shown by B in FIG. 9, the joint is in a locked state.

Further, when the solenoid coil 92 is on, the valve means 3
8 moves rightward in the figure to open the orifice 95.

Therefore, the joint becomes free, as shown by E in FIG. In this way, in this embodiment, control can be performed in three positions.

This control is suitable for inexpensive systems such as manual switching. Of course, it is also possible to control so that all three positions are automatically selected.

Note that the same effects as in the above embodiment can be obtained in this embodiment as well.

[Effects of the Invention] As explained above, according to the present invention, the movable magnetic piece housed in the center of one rotating member in the axial direction,
In addition to directly operating the flow resistance control means, the magnetic frame and solenoid coil, which together with the movable magnetic piece constitute the solenoid, are fixed to a non-rotating third member and held in a non-contact manner with the movable magnetic piece. It is possible to eliminate deterioration in control accuracy due to oil leakage and decrease in durability due to wear of the rotary shaft seal, which were problems with rotary shaft seals.

Furthermore, it is possible to eliminate the problems of interruptions in power supply due to dancing of the brush at high rotation speeds and wear of the slip ring of the brush, which were problems when power was supplied to a rotating solenoid using a slip ring.

Furthermore, since no hydraulic pressure source is required for control, costs can be reduced.

As a result, it is possible to provide a hydraulic power transmission joint that is low cost, has high control accuracy, and has excellent durability.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing the first embodiment of the present invention, Fig. 2 is a diagram showing the arrangement of the joint, Fig. 3 is a graph showing torque characteristics, and Fig. 4 is a diagram showing the second embodiment of the invention. 5 is a graph showing torque characteristics; FIG. 6 is a sectional view showing a third embodiment of the present invention; FIG. 7 is a graph showing torque characteristics; FIG. 8 is a fourth embodiment of the present invention. FIG. 9 is a graph showing torque characteristics. In the figure, {... rotor (first rotating member), 2, 3... casing, 4.5... bearing, 6... needle bearing, 7... dripping sprocket, 8 ... Drive sprocket, 9... Chain, 10... Output flange, l1... Nut, 12.13... Oil seal, l4... Stop ring, l5... Thrust washer, 16. ... Plunger chamber, 17... Plunger 18... Cam housing (second rotating member) 18A.
...Cam surface, 19...Suction path, 20...Suction valve, 21...Return spring, 22...Plug, 23...Return spring, 24...Discharge path, 25... Discharge valve, 26... Return spring, 27... Main passage, 28... Outlet hole, 29... High pressure chamber, 30... Passage, 31... Plug, 32... Piston, 33 ...Return spring, 34.35...Oil seal, 36...Stop ring, 37...Thrust washer, 38...Valve means, 39...Cylinder body, 40...Movable magnetic body , 41...Communication hole, 42...Return spring, 43...Magnetic frame, 44...Solenoid coil, 46...Cover 51...Engine, 52...Transmission, 53... Transfer 54...Main shaft, 55.56...Bearing, 57...Coupling, 58...Right front wheel, 59...Left front wheel, 60...Right rear wheel, 61...Left rear Wheel, 62... Front wheel side differential gear device, 63...
- Rear wheel side differential gear device, 64... Front wheel side blower shaft, 65... Rear wheel side propeller shaft, 71... Orifice valve, 72... Orifice, 73... Return spring, 4. ...Holding member, 5...Oil seal, 6...Stopper 1...21 dollar valve, 2...Storage hole, 3...Orifice, 4...Relief hole, 1.92...・Solenoid coil, 3...check ball, 4...spring, 5...orifice.

Claims (1)

[Claims] A hydraulic pump driven by a difference in rotational speed between first and second rotary members that are relatively rotatable, and a flow resistance that is generated in a discharge path of the hydraulic pump in accordance with an external control signal. The hydraulic power transmission joint is provided with a control means for controlling the transmission torque between the first and second rotating members by an external control signal, wherein the hydraulic power transmission joint is movable in the axial direction to the center of the one rotating member. The movable magnetic body housed in the magnetic frame, the magnetic frame fixed to the non-rotating third member, and the solenoid coil are held in a non-contact state, and the whole constitutes an electromagnetic actuator, and the actuator controls the flow resistance. Hydraulic power transmission coupling characterized by direct actuation of the means.