JP2815737B2 - Hydraulic power transmission coupling - Google Patents

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 coupling capable of freely controlling a torque transmission characteristic with respect to a rotational speed difference between two power rotary shafts.

[0002]

Conventionally, as such a hydraulic power transmission joint, for example, Japanese Patent Application flat No. 1-154228 (JP-3
-56720) . The hydraulic power transmission joint is configured to respond to a hydraulic pump driven by a rotational speed difference between a first rotatable member and a second rotatable member that are rotatable relative to each other, and to a discharge path of the hydraulic pump in response to an external control signal. Flow resistance control means for generating flow resistance,
An electromagnetic actuator that acts on a central portion of the first or second rotating member in an axial direction of the first or second rotating member by controlling a transmission torque between the first and second rotating members by an external control signal. By directly operating the flow resistance control means by this electromagnetic actuator,
The torque transmission characteristic between the first and second rotating members is controlled.

[0003]

However, in such a conventional hydraulic power transmission joint, the above-mentioned electromagnetic actuator is constructed so as to be continuously connected to the shaft centers of the first and second rotating members. Therefore, when it is attached to the output shaft end of a transfer for a four-wheel drive vehicle, it becomes difficult to attach it to the vehicle or a large space for attachment must be secured. There was a problem with the wearability.

In order to control the flow resistance in three stages, two solenoid coils for driving a movable magnetic body provided in an electromagnetic actuator are required.
There was also a problem that the device became large. The present invention has been made in view of such a conventional problem, and it is an object of the present invention to provide a smaller hydraulic power transmission coupling that does not have the above-described problems by improving the structure of the electromagnetic actuator. Aim.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a hydraulic pump provided between input / output shafts which are rotatable relative to each other and driven by differential rotation of the input / output shafts. A control valve provided at the outlet of the hydraulic pump for controlling the flow resistance of the discharge hydraulic pressure; and an actuator for operating the control valve by an external signal, the rotational speed difference between the input / output shaft and an external control signal. A hydraulic power transmission coupling that transmits torque according to the solenoid coil, a solenoid coil, a magnetic frame surrounding the solenoid coil and held in a non-contact state with the coupling, and energizing the solenoid coil. Change the current step by step
A movable magnetic body as the actuator, which is displaced stepwise, is provided concentrically with respect to the input / output shaft, and a plurality of spring members having different spring forces for urging the movable magnetic body are provided . When the opening area is changed in accordance with the displacement of the movable magnetic body as a control valve, and not subject to hydraulic reaction force from the pressure oil control
It provided with a control valve.

[0006]

According to the hydraulic power transmission coupling of the present invention having such a configuration, the hydraulic power transmission coupling is fixed to an external member,
Around the solenoid coil and the solenoid coil, making no contact with the joint
The magnetic frame held in the state and the solenoid coil
Displacement stepwise by changing the conduction current stepwise
A movable magnetic body as an actuator is
Since they are provided concentrically, the length in the axial direction can be reduced.

Also, since only one solenoid coil is required,
Small size and low cost can be realized. Furthermore, since there is no need to control the hydraulic power transmission joint by directly contacting it from the outside, and the power transmission characteristics can be controlled in a non-contact manner, the durability and reliability can be improved. Also, the control means for controlling the current flowing through the solenoid coil can be easily realized with a simple electric circuit or the like, so that a so-called controller for controlling the hydraulic power transmission coupling can be miniaturized and simplified. can do.

Further, since the opening area of the control valve changes stepwise according to the displacement of the movable magnetic body, the torque transmission characteristic can be set stepwise, which is excellent as control for exhibiting vehicle performance. I have.

[0009]

An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1 showing the overall structure, reference numeral 2 denotes an input shaft to which a driving force is input, and 4 denotes a housing made of a magnetic material rotatably supported on the input shaft 2 via a bearing 6. Spline joint 8 formed in
Is connected to an output shaft (not shown).

A slidable accumulator piston 10 is accommodated in a piston chamber formed on the spline joint 8 side of the housing 4, and a left side is provided by a return spring 14 interposed in a retainer 12 fixed inside the housing 4. And the oil seal 16 and the O-ring 1
At 7, the piston chamber is sealed. Reference numeral 18 denotes a cam provided on the housing 4 via a thrust needle 20. A cam surface 22 of the cam 18 has a plurality of cam ridges and cam valleys alternately formed one by one as shown in FIG. .
Projections 18 a are provided at predetermined intervals on the outer periphery of the cam 18, and the same number of positioning projections 4 are provided inside the housing 4.
The cam 18 is rotatable within an angle θ at which the projections 18a and 4a do not abut.

The angle θ at which the cam 18 can rotate with respect to the housing 4 is set to θ す る と π / Nc, where Nc is the number of cam ridges of the cam 18. In this embodiment, the number Nc of the cam peaks and the cam valleys is set to five. Reference numeral 24 denotes a rotor spline-fitted to the input shaft 2, and a plurality of plunger chambers 26 are formed along the circumferential direction. The number of plunger chambers 26 is determined by a predetermined relationship based on the number Nc of cam ridges provided on the cam surface 22 of the cam 18. In this embodiment, nine plungers are provided for five cam lobes. Chambers 26 are formed at equal intervals.

A plunger 28 is accommodated in each plunger chamber 26 via a return spring 30 so as to be able to move forward and backward, and a suction / discharge hole 32 is formed at the bottom of each plunger chamber 26. Reference numeral 34 denotes a rotary valve, which is integrally fixed to the inner wall of the housing 4 to rotate integrally therewith, and to rotate the input shaft 2 via a ball bearing 36.
Are supported so as to be relatively rotatable with respect to

On the surface of the rotary valve 34 facing the rotor 24, five suction ports 38 and five discharge ports 40 are provided.
Are formed alternately at equal intervals, and the suction port 38 is further formed with a suction passage 42 communicating with an oil supply portion 44 outside the rotor 24. The discharge port 40 is not shown in FIG. 1 for explanation because it is located at a location that cannot be represented in the vertical cross-sectional view of FIG. 1. However, as shown in FIG. The low pressure suction passage 42 and the oil supply unit 44 do not communicate with each other, but communicate with a high pressure chamber 46 to be described later via a discharge passage 45. That is, the suction port 38 is provided for supplying oil from the low-pressure suction passage 42 to the suction / discharge hole 32 of the rotor 24 that is in the suction stroke, and the discharge port 40 is connected to the suction / discharge hole 32 of the rotor 24 that is in the discharge stroke. It is provided to supply the discharged pressure oil to a high-pressure chamber 46 described later via a discharge path 45.

Next, the relative relationship among the cam 18, the rotor 24, the plunger 28 and the rotary valve 34 will be described with reference to FIGS.
It will be described in detail together with. First, in FIG. 4, a cam 18 is mounted inside the housing 4, and a plurality of projections 4a, 18a provided respectively allow relative rotation within a predetermined angle θ range. As described above, since the cam surface 22 of the cam 18 is formed with five cam ridges and cam valleys, the angle β formed between the uppermost point of each cam ridge and the lowermost point of the cam valley is 36. °. Further, the nine plungers 28 facing the cam surface are positioned at 40 ° intervals, as shown by the dashed-dotted circle in FIG.

As shown in FIG. 5, the rotary valve 34 has five suction ports 3 on a surface facing the rotor 24.
8 and the discharge port 40 are provided alternately, so that the angle γ formed by the suction port 38 and the discharge port 40 is 36 °. Further, the plunger 28 and the suction / discharge hole 32 face the rotor 24 in opposition to the suction port 38 and the discharge port 40, as shown by a dashed line circle.

When the rotor 24 rotates relative to the housing 4 and the rotary valve 34 in the direction of arrow D in FIG. 4, the cam 18 rotates together with the rotor 24.
When the projection 4a of the housing 4 comes into contact with the projection 18a of the cam 18, the relative rotation stops, and the cam surface 22
The plunger 28, which operates from the cam valley to the cam valley, operates in the discharge stroke to discharge the pressure oil in the plunger chamber 26 from the suction / discharge hole 32, while the plunger operates from the cam valley to the cam valley. Reference numeral 28 indicates the operation of the suction stroke, and sucks oil into the plunger chamber 26. Further, the same suction / discharge process is performed even when the rotation is performed in the direction opposite to the arrow D.

The notches 34a of the rotary valve 34 shown in FIG. 5 are provided for fitting and fixing to the inner wall of the housing 4. The vertical sectional view of FIG.
3 shows a cross section of the entire joint in a positional relationship along the line α-α, and a partial longitudinal sectional view of FIG. 3 shows a cross section of the positional relationship between the discharge port 40 and the plunger 28 where the discharge process is performed in FIG. For example, a portion indicated by a two-dot chain line δ in the drawing) is shown.

Referring again to FIG. 1, the structure of the rotary valve 34 is formed with a high-pressure chamber 46 communicating with all the discharge ports 40 (see FIG. 3).
6, a first spool hole 47 penetrating in a direction parallel to the central axis Q is formed.
A first spool 48 is inserted therein so as to be able to advance and retreat.
Further, the suction passage 42 is provided at a location different from the first spool hole 47.
A communication hole 52 is formed which communicates with the communication shaft and penetrates to the left end of the rotary valve 34.

Further, the rotary valve 34 has a high-pressure chamber 4
A second spool hole 49 is formed to communicate with the other end of the second spool 6 and penetrate in a direction parallel to the central axis Q. A second spool 50 is inserted into the second spool hole 49 so as to be able to advance and retreat. . An orifice 54 is formed between one end of the second spool hole 49 and the suction passage 42. Reference numeral 56 denotes a cap-shaped cover made of a non-magnetic material, which is fixed to one end of the housing 4 with a retaining ring 58 and is sealed from the input shaft 2.

Reference numeral 60 denotes a movable magnetic material made of a ferromagnetic material, and has a first spool 48 and a second spool 50 at one end.
Is stuck. Reference numeral 62 denotes a cup-shaped positioning member made of a non-magnetic material, one end of which is loosely fitted to the movable magnetic material 60. Reference numeral 64 denotes a first spring interposed between one end of the movable magnetic body 60 and the end face of the rotary valve 34, and acts so as to separate the movable magnetic body 60 from the rotary valve 34.

Reference numeral 66 denotes a second spring interposed between one end of the movable magnetic body 60 and the positioning member 62, and acts in a direction to increase the distance between the movable magnetic body 60 and the positioning member 62. Furthermore, the structure of the movable magnetic body 60 and the positioning member 62 will be described with reference to FIG. 6. A large-diameter hole into which the input shaft 2 is inserted is formed at each bottom end. A locking groove 60a into which the locking projection 62a of the positioning member 62 is loosely fitted from the inside is formed.

Then, a first spring 64 is arranged between the outside of the positioning member 62 and the inside of the movable magnetic body 60, and the first spring 64 acts to separate the movable magnetic body 60 and the rotary valve 34. . Since the second spring 66 is interposed between the inside of the bottom end 62b of the positioning member 62 and the inside of the movable magnetic body 60, it acts so as to widen the mutual gap only between the movable magnetic body 60 and the positioning member 62. .

Referring again to FIG. 1, reference numeral 68 denotes a magnetic frame made of a magnetic material constituting a magnetic solenoid, 70 denotes a solenoid coil mounted on the magnetic frame 68, and the magnetic frame 68 faces the outer end of the housing 4. The solenoid coil 70 is formed in a cylindrical shape having a portion 68a fitted from the outside and a portion 68b opposed to the movable magnetic body 60.
The magnetic frame 68 is concentrically mounted on the magnetic frame 68.

The one end 68a of the magnetic frame 68 and the outer end surface of the housing 4 are not in contact with each other by a relatively narrow air gap, and the other end 68b is also in non-contact with the cover 56 by a relatively narrow air gap. Has become. In this embodiment, when no current is supplied to the solenoid coil 70 (hereinafter, referred to as a first control mode), a first control current having a current value I1 is supplied to the magnetic frame 68, the movable magnetic body. When the movable magnetic body 60 is moved by a predetermined distance against the spring force of the first spring 64 by the magnetic force F1 generated by the magnetic path generated between the rotary valve 34 and the housing 4 (hereinafter referred to as a second control) Mode) and a second control current having a current value I2 (where I2> I1) is supplied, whereby a magnetic path generated between the magnetic frame 68, the movable magnetic body 60, the rotary valve 34, and the housing 4 is generated. When the movable magnetic body 60 is moved by a fixed distance against the spring force of the first and second springs 64 and 66 by a magnetic force F2 (where F2> F1) (hereinafter, referred to as a third control mode). And setting the control mode for three positions settings, in order to obtain the three control modes, the magnetic force F1 of the control current in each control mode, F
2 and the spring force f of the first and second springs 64 and 66
1 and f2 are set as shown in FIG.

That is, in the first control mode in which no current flows through the solenoid coil 70, the movable magnetic body 60 is moved to the leftmost position by the first spring 64.
The amount of displacement of the movable magnetic body 60 is less than a fixed gap L1 provided between the bottom end 62b of the positioning member 62 and the end face of the rotary valve 34, and a normal torque transmission characteristic described later is obtained.

Next, in the second control mode, the spring force f1 of the first spring 64 and the spring force f1 of the second spring 66 are larger than the spring force f1 of the first spring 64.
Magnetic force F1 (ie, f1) smaller than the sum f1 + f2
1 <F1 <f1 + f2)
Is supplied. Thereby, the displacement amount L of the movable magnetic body 60 is in the range of L1 <L <L2, and the free characteristic described later is obtained.

In the third control mode, the spring force f1 of the first spring 64 and the spring force f2 of the second spring 66
And the magnetic force F2 (ie, f1 + f2 <F2) that is larger than the sum f1 + f2 and smaller than the magnetic force F3 within a certain safe range.
A second control current having a current value I2 for generating <F3) is supplied. Thus, the movable amount L of the movable magnetic body 60 is in the range of L2 <L <L3, and the lock characteristic described later is obtained.

As shown in FIG. 3, L1 is the movable stroke of the positioning member 62, that is, the bottom end 62b of the positioning member 62 and the rotary valve 34 when the movable magnetic body 60 moves to the leftmost position. L2 is a movable stroke of the movable magnetic body 60, that is, a gap between the movable magnetic body 60 and the end of the rotary valve 34 when the movable magnetic body 60 is moved to the leftmost position. is there.

Next, the operation of the embodiment having such a structure will be described. First, when the first control mode in which no current is supplied to the solenoid coil 70 is set, the movable magnetic body 60 is not affected by the electromagnetic solenoid as shown in FIG.
And is stopped by the leftmost spring 64. As a result, the first spool 48 closes the connection between the high-pressure chamber 46 and the communication hole 52, while the second spool 50 brings the high-pressure chamber 46 and the orifice 54 into communication.

The positional relationship between the cam 18, the rotor 24 and the rotary valve 34 in the first control mode is as shown in FIG. 9 which is developed on a straight line. And the cam 18
When a rotational speed difference occurs between the rotor and the rotor 24, when a certain plunger 28 is in the suction stroke (in a case indicated by an upper arrow), the suction port 38 of the rotary valve 34 and the suction and discharge hole 32 of the plunger chamber 26 communicate with each other. It becomes a positional relationship,
When oil is sucked from the suction passage 42 into the plunger chamber 26 through the suction and discharge holes 32 of the rotor 24 and a certain plunger 28 is in the discharge stroke (in the case indicated by a downward arrow), the relationship is opposite to that of the suction stroke. 24 leads to a plunger chamber 26. And such a plunger 28
The suction stroke and the discharge stroke of the nine plungers 28 alternately occur as shown in FIG. 9, and the discharge side and the suction side communicate with each other through the orifice 54 of the rotary valve 34. Therefore, the pressure corresponding to the flow resistance of the orifice 54 Is generated on the discharge side,
Torque transmission with a characteristic like a characteristic curve A in FIG. 12 is performed between the cam 18 and the rotor 24. The torque transmission characteristic A is adjusted according to the inner diameter of the orifice 54.

When a second control mode for supplying the first control current I1 to the solenoid coil 70 is set, a magnetic path is formed between the magnetic frame 68, the movable magnetic body 60, the rotary valve 34 and the housing 4, As shown in FIG.
The movable magnetic body 60 moves to the right by the magnetic force F1 corresponding to the first control current I1, and the bottom end 6 of the positioning member 62
2b stops at the position where it contacts the rotary valve 34.
At the same time, the first spool 48 also moves to the right by the amount that the gap between the bottom end 62b of the positioning member 62 and the rotary valve 34 disappears. As a result, the high pressure chamber 46 and the communication hole 52
The gap is opened, and the pressure oil in the high-pressure chamber 46 falls to the low-pressure suction path 42 side irrespective of the position of the second spool 50. Therefore, a so-called free state as shown by a characteristic curve B in FIG. 12 is obtained, and transmission torque cannot be obtained.

When a third control mode for supplying the second control current I2 to the solenoid coil 70 is set, FIG.
As shown in FIG. 1, the magnetic path corresponding to the control current I2 is
8, a magnetic force F2 generated between the movable magnetic body 60, the rotary valve 34 and the housing 4 (where F2> F
According to 1), the movable magnetic body 60 moves and stops until it comes into contact with the rotary valve 34 against the first and second springs 64 and 66. As a result, the first spool 48 closes the space between the high-pressure chamber 46 and the communication hole 52, and at the same time, the second spool 50 closes the space between the high-pressure chamber 46 and the orifice 54. Therefore, even if a difference in rotation speed occurs between the rotor 24 and the cam 18 and the pressure oil in the high-pressure chamber 46 rises due to the discharge stroke, the pressure oil is not released, so that a so-called lock as shown by the characteristic curve C in FIG. The properties of the state are obtained.

As described above, according to this embodiment, the first and second spools 48 and 50 are moved three times by moving the movable magnetic body 60 by the magnetic frame 68 and the solenoid coil 70 provided outside in a non-contact manner. By setting the position, a normal torque transmission, a free state, and a locked state can be switched and set. Next, another embodiment will be described with reference to FIGS. In this embodiment, the normal torque transmission, the free state, and the locked state are switched by one spool 72 instead of the first spool 48 and the second spool 50 provided on the movable magnetic body 60 shown in FIG. This is a structure that can be set. In these drawings, the same or corresponding parts as those in FIG. 1 are denoted by the same reference numerals, and the structure of the hydraulic pump including the cam 18, the rotor 24, the plunger 28 and the like is the same as that in FIG.

The difference from FIG. 1 is that the movable magnetic member 6
14 is inserted into a spool hole 74 that communicates with the high-pressure chamber 46.
As shown in FIG. 7, a slit-shaped through hole 76 is formed at a side end of the spool 72. When no current is supplied to the solenoid coil 70, the movable spring 60 and the spool 72 are moved to the leftmost position by the first spring 64 and stopped as shown in FIG. As a result, the opening amount of the communicating portion between the high-pressure chamber 46 and the through-hole 76 becomes maximum, and the oil in the high-pressure chamber 46 falls into the low-pressure suction passage 42 through the through-hole 76 and the hollow portion of the spool 72. No torque transmission is performed, and a so-called free state as shown by a characteristic curve B in FIG. 12 is obtained.

The first control current I is applied to the solenoid coil 70.
When 1 is supplied, a magnetic path is formed between the magnetic frame 68, the movable magnetic body 60, the rotary valve 34 and the housing 4,
As shown in FIG. 15, the movable magnetic body 60 is moved by the first spring 6 by the magnetic force F1 corresponding to the first control current I1.
4 moves to the right against the bottom end 62 of the positioning member 62.
b stops at the position where it contacts the rotary valve 34, and at the same time, the spool 72 also moves to the right by the amount that the gap between the bottom end 62b of the positioning member 62 and the rotary valve 34 disappears. As a result, a predetermined small portion of the high-pressure chamber 46 and the through hole 76 is in a communicating state, and the communicating portion exhibits a function as an orifice. In this state, input shaft 2
If there is a suction / discharge operation of the hydraulic pump due to a rotational speed difference between the housing and the housing 4, a pressure corresponding to the flow resistance due to the communication portion is generated on the discharge side, so that a characteristic like a characteristic curve A in FIG. Is transmitted.

The second control current I is supplied to the solenoid coil 70.
2 (I2> I1), a magnetic path corresponding to the control current I2 is formed in the magnetic frame 68 and the movable magnetic body 6 as shown in FIG.
0, which occurs between the rotary valve 34 and the housing 4, until the movable magnetic body 60 abuts on the rotary valve 34 against the first and second springs 64 and 66 due to the magnetic force F2 (where F2> F1). Move and stand still.
As a result, communication between the through hole 76 of the spool 72 and the high-pressure chamber 46 is interrupted, and the high-pressure chamber 46 is in a sealed state. Therefore, even if the pressure oil in the high-pressure chamber 46 rises due to the discharge stroke of the hydraulic pump, the pressure oil is not released, so that a so-called locked state characteristic as shown by a characteristic curve C in FIG. 12 is obtained.

As described above, according to this embodiment, the torque transmission, the free state and the locked state can be set by controlling the moving position of one spool 72 by the movable magnetic body 60, thereby simplifying the structure. In addition, downsizing can be achieved. Still another embodiment will be described with reference to FIGS. In this embodiment, the movable magnetic body 6 shown in FIG.
A first spool 48 and a second spool 5 provided at
The structure is such that the normal torque transmission, the free state, and the locked state can be switched and set by one spool 78 instead of zero. In these drawings, the same or corresponding parts as those in FIG. 1 are denoted by the same reference numerals, and the structure of the hydraulic pump including the cam 18, the rotor 24, the plunger 28 and the like is the same as that in FIG.

The difference from FIG. 1 is that the movable magnetic member 6
A spool 78 fixed to one end of the spool 78 is inserted into a spool hole 80 communicating with the high-pressure chamber 46. Further, as shown in FIG. 18, a notch groove 82 is formed which gradually becomes deeper from the side end to the tip of the spool 78. I have. Solenoid coil 70
If no current is supplied to the movable magnetic member 60 and the spool 78 by the first spring 64, the movable magnetic member 60 and the spool 78 move to the leftmost position and stop, as shown in FIG. As a result, the opening amount of the communicating portion between the high-pressure chamber 46 and the notch groove 82 is maximized, and the oil in the high-pressure chamber 46 falls into the low-pressure suction passage 42 through the notch groove 82, so that torque transmission is not performed. A so-called free state as shown by a characteristic curve B in FIG.

The first control current I is applied to the solenoid coil 70.
When 1 is supplied, a magnetic path is formed between the magnetic frame 68, the movable magnetic body 60, the rotary valve 34 and the housing 4,
As shown in FIG. 19, the movable magnetic body 60 is moved by the first spring 6 by the magnetic force F1 corresponding to the first control current I1.
4 moves to the right against the bottom end 62 of the positioning member 62.
b stops at the position where it contacts the rotary valve 34, and at the same time, the spool 78 also moves to the right by the amount that the gap between the bottom end 62b of the positioning member 62 and the rotary valve 34 disappears. As a result, a predetermined small portion of the high-pressure chamber 46 and the notch groove 82 communicate with each other, and this communication portion functions as an orifice. In this state, input shaft 2
If there is a suction / discharge operation of the hydraulic pump due to a rotational speed difference between the hydraulic pump and the housing 4, a pressure corresponding to the flow resistance due to the communication portion is generated on the discharge side, so that a characteristic like a characteristic curve A in FIG. Is transmitted.

The second control current I is supplied to the solenoid coil 70.
20 (I2> I1), a magnetic path corresponding to the control current I2 is formed in the magnetic frame 68 and the movable magnetic body 6 as shown in FIG.
0, which occurs between the rotary valve 34 and the housing 4, until the movable magnetic body 60 abuts on the rotary valve 34 against the first and second springs 64 and 66 due to the magnetic force F2 (where F2> F1). Move and stand still.
As a result, communication between the notch groove 82 of the spool 78 and the high-pressure chamber 46 is cut off, and the high-pressure chamber 46 is in a sealed state. Therefore, even if the pressure oil in the high-pressure chamber 46 rises due to the discharge stroke of the hydraulic pump, the pressure oil is not released, so that a so-called locked state characteristic as shown by a characteristic curve C in FIG. 12 is obtained.

As described above, according to this embodiment, the torque transmission, the free state and the locked state can be set by controlling the moving position of one spool 78 by the movable magnetic body 60, so that the structure can be simplified and the structure can be simplified. The size can be reduced.

[0042]

According to the present invention as described above, according to the present invention, the outer
Fixed to the member of the part, the solenoid coil and the solenoid
A magnet surrounding the coil and held out of contact with the joint
The air current and the current flowing through the solenoid coil are
Actuator that is displaced stepwise by changing
All the movable magnetic bodies are provided concentrically with respect to the input / output axis.
Thus, the length in the axial direction can be reduced. Further, since only one solenoid coil is required, the size and cost can be reduced.

Further, there is no need to control the hydraulic power transmission joint by directly contacting it from outside, and the power transmission characteristics can be controlled in a non-contact manner, so that the durability and reliability can be improved. . Further, since a control means for controlling the current supplied to the solenoid can be easily realized by a simple electric circuit or the like, a so-called controller for controlling the hydraulic power transmission joint is reduced in size and simplified. be able to.

Further, since the opening area of the control valve changes stepwise according to the displacement of the movable magnetic body, the torque transmission characteristic can be set stepwise, which is excellent as control for exhibiting vehicle performance. I have.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an entire structure of an embodiment of the present invention.

FIG. 2 is a perspective view showing a shape of a cam.

FIG. 3 is a partial cross-sectional view for explaining a positional relationship between a high-pressure chamber and a discharge port.

FIG. 4 is an explanatory diagram showing a positional relationship between a cam and a plunger.

FIG. 5 is an explanatory diagram showing a structure of a rotary valve and a positional relationship between plungers.

FIG. 6 is a perspective view showing shapes of a movable magnetic body and a positioning member.

FIG. 7 is an explanatory diagram illustrating a relationship between a driving force for driving the movable magnetic body and a spring force of a spring provided on the movable magnetic body.

FIG. 8 is a partial cross-sectional view for explaining an operation during torque transmission.

FIG. 9 is a cross-sectional view showing a cam and a plunger portion developed on a straight line in order to further explain the operation during torque transmission.

FIG. 10 is a partial cross-sectional view for explaining an operation in a free state.

FIG. 11 is a partial cross-sectional view for explaining an operation in a locked state.

FIG. 12 is a characteristic diagram showing power transmission characteristics.

FIG. 13 is a cross-sectional view showing a main part structure for explaining a structure of another embodiment.

FIG. 14 is a partial perspective view showing a shape of a spool in another embodiment.

FIG. 15 is a partial cross-sectional view for explaining an operation during torque transmission in another embodiment.

FIG. 16 is a partial cross-sectional view illustrating an operation in a locked state according to another embodiment.

FIG. 17 is a cross-sectional view showing a main part structure for describing a structure of still another embodiment.

FIG. 18 is a partial perspective view showing a shape of a spool in still another embodiment.

FIG. 19 is a partial cross-sectional view for explaining an operation at the time of torque transmission in still another embodiment.

FIG. 20 is a partial cross-sectional view for explaining an operation in a locked state of still another embodiment.

[Explanation of symbols]

 2; input shaft 4; housing 4a; protrusion 8; spline joint 10; accumulator piston 18; cam 18a; protrusion 22; cam surface 24; rotor 26; plunger chamber 28; plunger 30; Notch 38; suction port 40; discharge port 42; suction path 44; oil supply section 45; discharge path 46; high-pressure chamber 47; first spool hole 48; first spool 49; Hole 50; second spool 52; communication hole 54; orifice 56; cover 58; retaining ring 60; movable magnetic body 60a; locking groove 62; positioning member 62a; locking projection 62b; bottom end 64; Spring 66; Second spring 68; Magnetic frame 70; Solenoid coil 72; Spool 74; 76; through hole 78; spool 80; spool hole 82; notch groove

Claims (1)

(57) [Claims] 1. A hydraulic pump provided between input / output shafts rotatable relative to each other and driven by differential rotation of the input / output shafts, and a flow resistance of a discharge hydraulic pressure provided at an outlet of the hydraulic pump. A hydraulic power transmission coupling, comprising: a control valve; an actuator for operating the control valve according to an external signal; and transmitting a torque corresponding to a rotational speed difference between the input / output shaft and an external control signal. And a magnetic frame surrounding the solenoid coil and the solenoid coil and held in a non-contact state with the joint, and a stepwise change in the current supplied to the solenoid coil.
A plurality of spring members having different spring forces for biasing the movable magnetic body are provided concentrically with respect to the input / output shaft, the movable magnetic body serving as the actuator being displaced in a stepwise manner. And a control valve having an opening area that changes according to the displacement of the movable magnetic body and that does not receive a hydraulic reaction force from pressurized oil as the control valve.