JPH0587160A - Hydraulic power transmission joint - Google Patents

Abstract

PURPOSE:To miniaturize and lighten the joint by changing the spool valve orifice opening area of a movale magnetic body by the movable magnetic body for generating attractive force according to the current of a solenoid, and a spring for generating load proportional to the displacement quantity. CONSTITUTION:When a current is not applied to a solenoid coil 27, a movable magnetic body 28 does not generate magnetic attractive force, nor is generated the load of a spring 29, and an orifice 21 is fully opened so that oil flows to the orifice 21 and an intake passage 11 from a high pressure chamber 15 to place a torque characteristic in the free state. When the current is made larger and rotational difference is generated between a cam 2 and a rotor 3 in this state, a plunger supplies oil in a plunger chamber 5 into the intake passage 11, and the oil pressure of the plunger chamber 5 rises by the resistance of the orifice 21 to transmit torque between the cam 2 and the rotor 3. When the current is made further larger and the load of the spring 29 reaches the specified value, the movable magnetic body 28 comes in contact with a valve 9, so that the torque characteristic is placed into the lock state. The orifice opening can be thus continuously variable while miniaturizing and lightening.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic power transmission joint used for distributing driving force of a vehicle.

[0002]

2. Description of the Related Art The present applicant has proposed the following hydraulic power transmission joint in Japanese Patent Application No. 1-154228. That is, this hydraulic power transmission joint responds to a hydraulic pump driven by the rotational speed difference between the first and second rotating members which are relatively rotatable, and a control signal from the outside to the discharge passage of the hydraulic pump. In a hydraulic power transmission joint including control means for generating a flow resistance, and a transmission torque between the first and second rotating members is controlled by a control signal from the outside, a shaft is provided at a central portion of the one rotating member. The movable magnetic body housed so as to be movable in the direction, the magnetic frame fixed to the non-rotating third member, and the solenoid coil are held in a non-contact state to form an electromagnetic actuator as a whole, and the actuator is used to The flow resistance control means is directly operated.

Further, as one of the embodiments, a joint is proposed in which three positions of normal characteristic, free characteristic and lock characteristic are selected by using two solenoid coils.

[0004]

However, in such a conventional hydraulic power transmission joint, since two solenoid coils are used, there is a problem that it is expensive, large and heavy. .. Further, since the control mechanism is arranged at the center of the shaft, there is a problem that the method of mounting the control mechanism on the vehicle is limited.

Further, there are vehicles in which three positions are not sufficient, and there has been proposed a continuous control through a link mechanism by an externally provided stepping motor, but in this case, it is expensive and complicated. There was a problem that it became a structure. The present invention has been made in view of such conventional problems, and requires only one solenoid coil,
It is an object of the present invention to provide a hydraulic power transmission joint which is inexpensive, small-sized, lightweight, and is not limited in its mounting method on a vehicle, and which can continuously control the orifice opening with a simple structure.

[0006]

In order to achieve the above-mentioned object, the present invention is provided between input / output shafts capable of relative rotation,
A hydraulic pump driven by the differential rotation of the both shafts;
A control valve provided at the outlet of the hydraulic pump for controlling the flow resistance of the discharged oil; and an actuator for operating the control valve in response to an external signal; a rotational speed difference between the two shafts and an external control signal In a hydraulic power transmission joint that transmits torque according to; fixed to an external member,
A magnetic frame that houses one solenoid coil and is held in a non-contact state with a joint, a movable magnetic body that generates a magnetic attraction force by energizing the solenoid coil, and interlocks with the movement of the movable magnetic body. A movable magnetic body that is continuously displaced by continuously changing the current passed through the solenoid coil, and the displacement of the movable magnetic body is changed. A spool valve is provided as the control valve whose opening area changes accordingly and which is not affected by the hydraulic reaction force from the pressure oil.

[0007]

In the present invention, the movable magnetic body that generates an attractive force according to the strength of the current flowing through one solenoid coil and the spring member that generates a load proportional to the displacement amount of the movable magnetic body The orifice opening area of the spool valve provided on the movable magnetic body is continuously changed according to the amount of displacement corresponding to the strength of the current.

As described above, the orifice opening can be continuously varied with a simple structure and at low cost. Also,
Since continuous control can be performed by energizing the solenoid coil, power loss is reduced as compared with control by a hydraulic multi-plate clutch or an electromagnetic clutch.

Further, since only one solenoid coil is required, cost reduction, size reduction and weight reduction can be achieved. Furthermore, there are no restrictions on mounting on vehicles.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 6 are views showing an embodiment of the present invention.
First, the configuration will be described. In FIG. 1, reference numeral 1 denotes a magnetic body housing. The housing 1 is connected to an output shaft (not shown) and rotates integrally with the output shaft.

Reference numeral 2 is a cam, and the cam 2 is supported on the inner surface of the housing 1 so as to be rotatable by a predetermined angle. Cam 2
It has a cam surface 2A composed of a plurality of cam ridges and a cam valley, and has a plurality of protrusions 2B for positioning and torque transmission on the outer periphery thereof where the cam ridges are on the side surfaces. When the projection 2B of the cam 2 is engaged with the notch 1A formed in the housing 1 to rotate integrally with the housing 1 in the rotation direction of the rotor 3, and when the rotation direction of the rotor 3 changes, the cam 2 moves to the rotor 3
And the projection 2B of the cam 2 is rotated together with the housing 1
After rotating until it hits the notch 1A, it rotates integrally with the housing 1.

The rotor 3 is rotatably accommodated in the housing 1, is coupled to the input shaft 4, and rotates integrally with the input shaft 4. The rotor 3 includes a plurality of plunger chambers 5 in the axial direction.
A plurality of plungers 6 are slidably accommodated in the plunger chamber 5 via return springs 7. Further, the rotor 3 is formed with a plurality of suction / discharge holes 8 so as to communicate with the respective plunger chambers 5.

Reference numeral 9 denotes a magnetic valve (valve body) in which a suction port 10, a suction passage 11 and a discharge port 12 are formed. The valve 9 has a projection 13 on a notch 1A of the housing 1.
Are engaged with and fixed to the housing 1. A bearing 14 is mounted between the input shaft 4 and the inner diameter portion of the valve 9, and a ring-shaped groove formed in the inner diameter portion of the valve 9 is sealed by the outer diameter surface of the bearing 14 to form a high pressure chamber 15. ..

Reference numeral 16 denotes a communication passage formed in the valve 9, and the storage chamber 18 defined by the non-magnetic cover 17 and the suction passage 11 communicate with each other through the communication passage 16. Further, the discharge port 12 is connected to the high pressure chamber 1 via the passage 19.
5, the high pressure chamber 15 can communicate with the suction port 10 through a slit-shaped orifice (flow resistance generating means) 21 formed in a spool valve (control valve) 20 movably inserted in the valve 9. Is becoming

When the plunger 6 is in the suction stroke,
The suction port 10 of the valve 9 and the suction / discharge hole 8 of the rotor 3 are in a positional relationship of communicating with each other, and the orifice 21, the suction passage 11,
Oil can be sucked into the plunger chamber 5 through the suction port 10 and the suction / discharge hole 8 of the rotor 3. Further, when the plunger 6 is in the discharge stroke, the relationship is opposite to that in the suction stroke, and the suction / discharge hole 8 of the rotor 3 has the valve 9
To the high pressure chamber 15 via the discharge port 12 and the passage 19.

Reference numeral 23 is an accumulator piston that rotates integrally with the housing 1. The accumulator piston 23 is provided to absorb thermal expansion of the enclosed oil. Reference numeral 24 is a retainer fixed to the housing 1, and a return spring 25 is interposed between the retainer 24 and the accumulator piston 23.

Reference numeral 26 is a magnetic frame, and the magnetic frame 26 is fixed to an external member and held in a non-contact state with the joint. That is, as shown in FIG. 2, an air gap A is formed between the magnetic frame 26 and the housing 1, and an air gap B is formed between the magnetic frame 26 and the non-magnetic cover 17. The magnetic frame 26 is arranged concentrically with respect to the joint axis,
A solenoid coil 27 is housed in the magnetic frame 26.

Reference numeral 28 denotes a movable magnetic body that generates a magnetic attraction force by energizing the solenoid coil 27. The movable magnetic body 28 is covered with a non-magnetic cover 17 that keeps the oil in the joint sealed. An air gap C is formed between the movable magnetic body 28 and the valve 9. By energizing the solenoid coil 27 in this manner, a magnetic path is formed between the magnetic frame 26, the movable magnetic body 28, the valve 9 and the housing 1 as shown in D of FIG.

Reference numeral 29 is a spring (spring member) interposed between the valve 9 or the bearing 14 and the movable magnetic body 28, and the load of the spring 29 continuously changes as the movable magnetic body 28 moves. It is like this. Movable magnetic body 28
Is formed in a ring shape, and the movable magnetic body 28 is provided with a spool valve 20 that continuously controls the orifice opening degree according to the displacement thereof, away from the center of the joint shaft.

As shown in FIG. 3, the spool valve 20 is formed in the shape of a pipe, has a hollow portion 30 inside, and has a slit-shaped orifice 21 at a predetermined position.
The spool valve 20 is inserted into the valve 9 and does not receive the hydraulic reaction force from the pressure oil. Incidentally, 31 in FIG. 1 is a stopper ring,
32 and 33 are needle bearings, 34 is an oil seal, and 35 is a spline.

Next, the operation will be described. When the solenoid coil 27 is not energized, the movable magnetic body 28 does not generate a magnetic attraction force as shown in FIG.
The movable magnetic body 28 is in contact with the movable body 7. That is,
As shown in FIG. 5, when the current I does not flow, the magnetic attraction force H is not generated, the spring load J is not generated, and the movable magnetic body 2
There is no displacement K of 8, and the orifice 21 is in the fully opened state E.

In this state, the oil flows from the high pressure chamber 15 through the orifice 21 and the hollow portion 30 to the suction passage 11 as shown by the arrow O in FIG. The torque characteristic at this time is shown by M in FIG. 6 and is in a free state. next,
When the current I to the solenoid coil 27 is increased and the magnetic attraction force H reaches the operating point G as shown in FIG. 5, torque transmission is performed.

That is, in this state, if there is a rotation difference between the cam 2 and the rotor 3, the plunger 6 in the discharge stroke is pushed axially by the cam surface 2A of the cam 2. At this time, since the suction / discharge hole 8 communicates with the discharge port 12, the plunger 6 pushes the oil in the plunger chamber 5 from the suction / discharge hole 8 to the discharge port 12 of the valve 9.

The oil pushed out to the discharge port 12 is
It is supplied to the suction passage 11 through the passage 19, the high pressure chamber 15, and the orifice 21. At this time, the hydraulic pressure of the high pressure chamber 15, the passage 19, the discharge port 12 and the plunger chamber 5 rises due to the resistance of the orifice 21, and a reaction force is generated in the plunger 6. A torque is generated by rotating the cam 2 against the plunger reaction force, and the torque is transmitted between the cam 2 and the rotor 3.

Further, when the cam 2 rotates, a suction stroke occurs, and the suction / discharge hole 8 communicates with the suction port 10. Therefore, the oil in the suction passage 11 enters the plunger chamber 5 through the suction port 10 and the suction / discharge hole 8. Inhaled, the plunger 6 returns along the cam surface 2A of the cam 2. The torque characteristic at this time becomes a torque characteristic between M and N in FIG. 6 depending on the magnitude of the current I.

Next, the current I further increases, and the magnetic attraction force H also increases accordingly, as shown in FIG.
When the spring load J reaches the predetermined value L, the movable magnetic body 28 contacts the valve 9 and the high pressure chamber 15 is closed by the spool valve 20 as shown in FIG. 4B. The torque characteristic at this time is in a locked state, as shown by N in FIG.

As described above, since the orifice opening can be easily continuously changed, it is possible to meet the needs of the vehicle side.
Compared with hydraulic multi-plate clutch control or electromagnetic clutch control, which has equivalent functions by control, power loss is reduced. In addition, the control logic on the vehicle side becomes simple. Further, since only one solenoid coil 27 is required, it is inexpensive, compact and lightweight. Furthermore, it can be penetrated through the shaft, and there is no restriction on mounting on a vehicle.

Next, FIGS. 7 and 8 show another embodiment of the present invention. In the present embodiment, as shown in FIG. 7, the spool valve 41 inserted and fixed in the movable magnetic body 28 is formed of a round bar, and the notch forms the orifice 42. When the solenoid coil 27 is not energized, the oil flows from the high pressure chamber 15 to the suction passage 11 through the fully opened orifice 42 as shown by an arrow P in FIG. become. As the current I is increased, the variable torque characteristic shown between M and N in FIG. 6 is obtained.

When the current I is further increased, FIG.
As shown in FIG. 6, the movable magnetic body 28 contacts the valve 9, and the high pressure chamber 15 is closed by the spool valve 41, so that the locking characteristic shown by N in FIG. 6 is obtained. Also in this embodiment, the same effect as that of the above embodiment can be obtained. Note that the control characteristics may be such that the relationship between the current I and the open state is reversed depending on the positions of the orifices 21 and 42. That is, the larger the current I, the closer to the free state it is possible.

[0030]

As described above, according to the present invention, only one solenoid coil is required, and low cost, downsizing and weight saving can be achieved. Further, the orifice opening can be continuously controlled with a simple structure, and the power loss can be reduced as compared with other hydraulic and electromagnetic clutch controls. Furthermore, there are no restrictions on mounting on vehicles.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing a magnetic circuit.

FIG. 3 is a perspective view of a spool valve.

FIG. 4 is a diagram showing a fully open state and a fully closed state.

FIG. 5 is a graph showing the relationship between spring load and displacement.

FIG. 6 is a graph showing torque characteristics

FIG. 7 is a view showing a spool valve according to another embodiment of the present invention.

FIG. 8 is a diagram showing a fully open state and a fully closed state of another embodiment.

[Explanation of symbols]

 1: Housing 1A: Notch 2: Cam 3: Rotor 4: Input shaft 5: Plunger chamber 6: Plunger 7: Return spring 8: Suction / discharge hole 9: Valve (valve element) 10: Suction port 11: Suction path 12: Discharge port 13: Protrusion 14: Bearing 15: High pressure chamber 16: Communication passage 17: Non-magnetic cover 18: Storage chamber 19: Passage 20: Spool valve (control valve) 21: Orifice (flow resistance generating means) 23: Accumulator Piston 24: Retainer 25: Return spring 26: Magnetic frame 27: Solenoid 28: Movable magnetic body 29: Spring 30: Hollow part 31: Stopper ring 32, 33: Needle bearing 34: Oil seal 35: Spline 41: Spool valve (control) Valve) 42: orifice (flow resistance generating means)

Claims (3)

[Claims] 1. A hydraulic pump provided between relatively rotatable input and output shafts and driven by differential rotation of both shafts; a control provided at an outlet of the hydraulic pump for controlling flow resistance of discharged oil. A valve and; an actuator for actuating the control valve in response to a signal from the outside; a hydraulic power transmission joint for transmitting a torque according to the rotational speed difference between the two shafts and the control signal from the outside; Fixed 1
A magnetic frame that houses individual solenoid coils and is held in a non-contact state with the joint, a movable magnetic body that generates a magnetic attraction force by energizing the solenoid coils, and a movable magnetic body that interlocks with the movement of the movable magnetic body. A spring member whose load changes, and by continuously changing a current flowing to the solenoid coil, a continuously displacing movable magnetic body is configured as the actuator, and the movable magnetic body is responsive to the displacement of the movable magnetic body. The hydraulic power transmission joint is characterized in that a spool valve serving as the control valve is provided, the opening area of which changes, and which does not receive a hydraulic reaction force from the pressure oil. 2. The hydraulic power transmission coupling according to claim 1, wherein the spool valve is formed in a hollow shape, and a slit-shaped orifice is formed on the outer circumference. 3. The hydraulic power transmission joint according to claim 1, wherein the spool valve is formed in a round rod shape, and an orifice is formed by a notch at an end portion.