JPS6283572A - Proportional electromagnetic valve - Google Patents

Abstract

PURPOSE:To perform stable control of fluid, by a method wherein a gap, on which an air-core coil part faces, is closed with magnetic fluid, a closed space is formed between a bobbin body and a second yoke, and a communicating hole, through which the closed space is communicated with the outside, is machined in the bobbin body. CONSTITUTION:A proportional electromagnetic valve 3 comprises a valve body 1, an air-core coil 33, and a valve body 23. A gap internally of which the air- core coil 33 is engaged is closed with magnetic fluid 45, and a closed space 47 is formed between a second yoke 43 and a coil bobbin 31. A communicating hole 49, communicated with the closed space 47, is formed in the coil bobbin 31. This enables to perform regulation through which the optimum damping effect of the coil bobbin is produced, permits a moving valve body to be converged in a desired position in a short time, and causes stable control of fluid.

Description

[Detailed description of the invention] [Industrial application field] This invention relates to a proportional solenoid valve.

[Prior Art] For example, Utility Model Application No. 59-119910K has been proposed as a proportional solenoid valve. This proportional solenoid valve has a sleeve 103 which holds a plurality of boats P in a valve body 101 as shown in FIG.
The movable valve body 105 that is assembled and slides inside the sleeve 103 has an air-core coil 107.
9 and is always at the neutral position (solid line) by the spring 111.
ni・] is being forced. The air-core coil 107 of the coil bobbin 109 faces within the interval between the first and second yokes 115 and 117 that sandwich the magnet 113, and when an applied voltage is applied to the air-core coil 107, the coil bobbin 109 is controlled to freely reciprocate. It has become.

Therefore, by displacement of the nJ valve body 105 to the right (arrow A), the first inlet port +-121 leading to the discharge port side of the hydraulic pump 119 and the second outlet port leading to the first chamber P1 of the power wheel ring 123. 129 respectively) 1), and hydraulic pressure from the hydraulic pump 119 is sent into the second chamber P2.

As a result, the piston rod 127 on the 21fP2 side expands, and the piston rod 127 on the first chamber P+ side can be reduced (as indicated by the arrow).

Also, by displacing the movable valve body 105 in the opposite direction (in the direction opposite to arrow A), the first inlet port 121
communicates with a first outlet boat 125 that continues to the first chamber P1 of the power cylinder 123. Further, the second outlet ports 129' communicate with drain ports 133 leading to the tank 131, respectively. As a result, hydraulic pressure is supplied into the first chamber P1, so that the first chamber P1
The piston rod 127 on the side extends, and the piston rod 127 on the second chamber P2 side can be contracted. Note that the first and second stopper members S are provided with movable valve bodies 105 at the front and rear.
1 - The opening area of each port is set to be maximized by contacting S2.

[Problems to be Solved by the Invention] In such a proportional electromagnetic valve, when an applied voltage is applied to the air-core coil 107 of the coil bobbin 109, the movable valve body 105 is displaced against the force of the spring 111 and reaches the target position.

In this case, the movement system when the movable valve body 105 reaches the target position is composed of the inertia of the movable valve body 105 and the spring 111 for returning the movable valve body, and the movable valve body 105 is rapidly displaced toward the target position. Since the inertial force moves when the movable valve body 105 is displaced, a problem arises in that it takes time for the movable valve body 105 to converge. This problem also occurs when the applied voltage applied to the air-core coil 107 is released; when the applied voltage is removed, the movable valve body 105 quickly returns to the neutral position due to the action of the spring 111, so it takes time to converge due to the inertia force at the time of return. There was a problem that it was difficult to control the fluid stably.

[Object of the Invention] Therefore, an object of the present invention is to provide a proportional solenoid valve that can perform stable fluid control with a simple device.

[Means for Solving the Problems] In order to achieve the above object, the present invention includes an air-core coil portion, and the coil portion is connected to a first yoke and a second yoke.
In the proportional solenoid valve, a movable valve body provided in a valve body and movable by the reciprocating motion of the coil bobbin is connected to a coil bobbin that reciprocates within a gap between the yoke, and the fluid is controlled by displacement of the movable valve body. The gap facing the air-core coil portion is closed with magnetic fluid to connect the bobbin main body of the coil bobbin and the second
A communication hole is formed in the bobbin body to form a closed space between the bobbin body and the yoke, and to communicate the closed space with the outside.

[Function] In such a proportional solenoid valve, when a positive applied voltage is applied to the air-core coil, the coil bobbin moves forward due to the action of electromagnetic force, and the movable valve body is displaced toward the target position, thereby controlling the fluid. . On the other hand, the inertia force when the movable valve body moves forward or backward is absorbed by the air resistance in the closed space that enters and exits through the communication hole provided in the coil bobbin, and is rapidly converged at the target position. .

[Embodiment] An embodiment of the present invention will be described in detail with reference to the drawings of FIGS. 1 to 6.

In the figure, 1 indicates the valve body of the proportional solenoid valve 3;
A sleeve 5 having a plurality of ports P is assembled inside. A side cover 5 is fitted on one side of the valve body 1, and a case 7 is fitted on the extension side.

The valve body 1 has a first inlet boat 1 connected to the pump 9.
1, the drain port 15 leading to the tank 13, and the two first chambers 17a and 2 leading to the second chamber 17b of the power cylinder 17.
- Second outlet ports 19 and 21 are respectively formed. The sleeve 5 has a first inlet boat 11.
an annular groove 5a communicating with the drain boat 15;
Two annular grooves 5b and 5C and two annular grooves 5d and 5e communicating with the first and second outlet ports 19.21 are formed, respectively. A movable valve body 23 (spool) is slidably fitted into the sleeve 5, and the movable valve body 23 has two protrusions 23a corresponding to the annular grooves 5d and 5e of the sleeve 5.

23b is formed, and three grooves 27.29a, 29b are set by the protrusions 23a, 23b.

Kore groove 27. , 29a, 29b Gt, depending on the displacement of the movable valve body 23, each of the annular grooves 5d and 5e is selectively communicated with the annular groove 5a or the annular grooves 5b and 5c, and each outlet port 19.21 is connected to the second inlet boat. 1
1 or drain port 15. Further, a coil bobbin 31 having a flange 31a is integrally connected to one side of the movable valve body 23. The roll bobbin 31 is housed in the case 7 so as to be movable along the axial direction.
An air-core coil 33 wound with a conducting wire is provided on the outer periphery of the flange 31a.

Both ends of the air-core coil 33 are connected to a drive circuit such as a servo amplifier to be described later, and when an applied voltage is applied to the coil 33, the current and the magnetic flux of the permanent magnet 39 change as expressed by Fleming's left-hand rule. Electromagnetic force acting perpendicularly to the direction An electromagnetic force acting perpendicularly to the direction of the three magnetic fluxes is generated. For this reason, air core coil 3
3, that is, the movable valve body 23 is urged by the electromagnetic valve J.

In addition, the thrust force F at this time is B: Magnetic flux density of the gap F = B-i - History (+) i: Current flowing through the coil A2 The length of the coil, and the force acting on the movable valve body 105 The equation of motion is the relation between the force [~E and Kerr spring force]. Immediately
, B1 hair-Kx K: spring religion Di O-...
・(2)

FIG. 6 shows a diagram of the relationship between the current and the movable valve body 23.

That is, as shown in the drawing, the displacement of the movable valve body 23 moves in proportion to the current in the forward and reverse directions, and when it exceeds the predetermined value Xo (overlap suspension) indicated by the broken line, the movable valve body 23 moves as described above. An opening area corresponding to the displacement of the valve body 23 is obtained. This allows one first outlet port and one
The inlet 1-port 11 is in communication with the second outlet 1-port 21 and the drain port 15 are in communication with each other. The opening area of each port is set to be maximized by contacting a first stopper $1 screwed 25 to the side cover 5 and a second stopper S2 to be described later. (1+) Also, the same is true when the predetermined value -X (overlap foil) shown by the broken line is exceeded, and the second outlet port 21 communicates with the first inlet port 11, contrary to the case (previously). One first outlet boat comes into communication with the drain port 15.

In addition, 35 indicates the right end of the movable valve body 23 in the figure and the side cover 5.
Similarly, a first seal 37 is installed between the coil bobbin 31 and the case 7 on the left side of the movable valve body 23 to prevent fluid leakage. This is the second seal that prevents this.

On the other hand, inside the case 7, there is a substantially annular permanent magnet 39 and first yokes 4 disposed on the left and right sides of the permanent magnet 39, respectively.
1 and a second yoke 43 are provided. 1st yoke 4
1 has a substantially annular shape, and a second yoke 43 is provided at the center frontage.
The shaft portion 43 of is facing. As a result, a gap is formed between the shaft portion 43a and the opening, and the air-core coil 33 is fitted into the gap so as to be able to reciprocate.

The gap into which the air-core coil 33 is fitted is closed by a magnetic fluid 45, and a closed space 47 is formed between the shaft portion 43a of the second yoke 43 and the bobbin body of the coil bobbin 31. The bobbin body of the coil bobbin 31 is provided with 1) four communication holes that communicate with the η2 closed space 47 through holes 81 and are arranged at four opposing locations.

The communication hole 49 connects the closed space 4 when the coil bobbin 31 reciprocates.
Coil it < Bin 31 due to the air resistance of the air entering and exiting
damping can be obtained. That is, the damping coefficient CP is as follows: CP=A2Rν (1) △: Internal diameter of the coil bobbin R: Viscosity f: Resistance d: Thickness of the coil bobbin d: Diameter of the communicating hole. By appropriately setting the diameter of the coil bobbin 31, it is possible to adjust the coil bobbin 31 so as to obtain the optimum gunbing effect.

Further, the permanent magnet 39. No. 13-41 OJ.

The magnetic circuit 51 is composed of the second yoke 43 and the second yoke 43 . The magnetic circuit 51 and the air-core coil 33 facing the circuit constitute a linear motor 45 for driving the movable valve body 23.

Further, the second yoke 43 is formed with three through holes along the axis, and a hollow spring holder 55 is screwed into the case 7 and fixed to the case 7 by a lock nut 53. is inserted. Inside the spring holder 55, a second stopper S2 that can come into contact with the left end of the coil bobbin 31 in the figure is screwed into the spring holder 55 with a lock nut 57 so that it can be fastened to the spring holder 55. This second stopper S2 restricts the maximum displacement of the movable valve body 23 in the left direction in the figure. In addition, 59 is a first central spring compressed between the coil bobbin 31 and the spring holder 55;
1 is a second central spring compressed between the case 7 and the coil bobbin 31, and these first central springs 5
9 and the second central spring 61 urge the movable valve body 23 to the neutral position.

Note that the first chamber 17a and the second chamber of the power cylinder 17
Piston rods 63 and 65 extend and protrude from the chamber 17b.
is conductively connected to the wheel 71 via the side rod 67 and knuckle arm 569. Therefore, by expanding and contracting the piston rods 63 and 65, the direction of the wheel 71, that is, the steering becomes possible.

In addition, B is a battery, 73 is an accumulator, 75
"indicates the control circuit," respectively.The control circuit 75 is
Vehicle speed sensor 77, steering angle sensor 79. Yaw rate sensor 8
The target steering angle is calculated and determined based on the input signal from 1. Further, the servo amplifier 83 outputs a current proportional to the deviation between the target steering angle from the control circuit 75 and the output of the amplifier 85 of the displacement sensor 83 that detects the cylinder position, and drives the proportional solenoid valve 3.

In the proportional solenoid valve 3 configured as described above, when a step voltage is applied to the air-core coil 33 at time tl as shown in FIG. 4(a), the coil bobbin 31 is
moves back and forth. The inertial force during the forward movement is absorbed by the air resistance when the air in the closed space 47 enters and exits through the communication hole 49, and the movable valve body 23 is converged in a short time as shown in FIG. 4(b). , the convergence time at this time is the same as the conventional example (Fig. 4 (C))
) will be significantly improved. As a result, stable fluid control can be performed. In this case, the fluid may be e.g.
When supplied into the first chamber 17a, the screws in the first chamber 17a [-
The locking rod 63 extends and moves to the left), and the second chamber 17b
By reducing the piston rod 65, the wheels 71 can be steered.

[Effects of the Invention] As explained above, according to the proportional solenoid valve of the present invention,
Since the movable valve body can be converged at the target position within a short time, stable fluid control can be performed.

[Brief explanation of drawings]

Fig. 1 is a sectional view of the proportional solenoid valve of the present invention, Fig. 2 is an enlarged view of the main parts, Fig. 3 is a sectional view taken along the line ■-■ in Fig. 2, Fig. 4 is an explanatory diagram of the operation, and Fig. 5 is a sectional view of the proportional solenoid valve of the present invention. The figure shows the overall 8! using a proportional solenoid valve in a vehicle steering system! ! 6 is an explanatory diagram of the operation, and FIG. 7 is a sectional view similar to FIG. 1 showing a conventional example. 4. Brief explanation of the drawings 1... Valve body 3... Proportional solenoid valve 23
...Movable valve body 31...Coil bobbin 33...Air core coil 4
1... First yoke 43... Second yoke 45
...Magnetic fluid 47...Closed space 49...
Communication hole patent applicant Nissan Motor Co., Ltd., Goji 1
Figure 8 Wisdom Figure 8 Figure 59

Claims (1)

[Claims] A movable valve body provided in a valve body and movable by the reciprocating motion of the coil bobbin is connected to a coil bobbin having an air-core coil portion and the coil portion reciprocating within a gap between a first yoke and a second yoke. In a proportional solenoid valve that controls fluid by displacement of a movable valve body, the gap facing the air-core coil portion is closed with a magnetic fluid to form a closed space between the bobbin body of the coil bobbin and the second yoke; A proportional solenoid valve characterized in that a communication hole is bored in the bobbin body to communicate the space with the outside.