JPH10196831A - Proportional solenoid control valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To proportionally control the displacement of a spool as an analog amount so as to reduce costs by providing a non-linear solenoid and a leaf spring to face each other holding the spool therebetween and supporting the leaf spring from its backside with a non-linear spring receiving seat. SOLUTION: When currents of a pair of left and right solenoids 10 are 0, a spool 5 is pulled back from a leaf spring 12 and its normal position is maintained. Then, when one solenoid 10 is energized, the solenoid 10 produces a non-linear attracting force matching a current and a suction gap in a plunger 11, presses the center part of one leaf spring 12 via a pushrod 34 and the spool 5, simultaneously deforms the leaf spring 12 in an arch shape and its effective spring length is reduced while the outside other end of the leaf spring 12 is in contact with the seat of one non-linear spring receiver 13. That is, the leaf spring 12 exerts a non-linear spring characteristics, and after balanced the spool 5 is displaced in proportion to the current and placed in a standstill state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a proportional electromagnetic control valve for controlling a fluid for hydraulic pressure.

[0002]

2. Description of the Related Art Conventionally, as this kind of proportional solenoid control valve,
For example, the one shown in FIG. 2 is known. This proportional electromagnetic control valve comprises a main body port 1 'having a valve chamber 2' connected to a main pipeline port 3,..., Ports P, A, B, T.
And a spool 5 'having a land 16,... And an annular groove 17
And a coil spring 26 for holding the spool 5 'slidably fitted in the valve chamber 2' at a normal position via a spring receiver 25, and opposing the coil spring 26 with the spool 5 'interposed therebetween. A return chamber 2 communicating with a proportional solenoid 24 and a control chamber 6 ′ defined by the spool 5 ′ in the valve chamber 2 ′ via a return communication path 48.
7 ', 27', the control room 6 'and the return room 2
7 ', 27' valve opening / closing portions 8,... As shown in detail in FIG. 3 (magazine: hydraulic and pneumatic, Vol. 22, No. 1, page 52), the proportional solenoid 24 includes a plunger 11 'having a plunger oil passage 29 and a push rod 34; A cartridge 18 'having a cartridge magnetically permeable material portion 30' and a cartridge non-magnetically permeable material portion 19 'and an oil passage 28 integrated with the cartridge non-magnetically permeable material portion 19' via a magnetic leakage portion 36. Yoke 31, the yoke 31, and the cartridge magnetically permeable member 3
0 ', a cup-shaped yoke 38 for magnetically connecting the solenoid, a solenoid chamber 9' sealed from the outside formed by the cartridge 18 'and the yoke 31, etc., a coil 14', a spacer 35, and a bearing. 33 and the like. Note that FIG.
3 further shows a differential transformer 39 and a driver 40. The above-described proportional electromagnetic control valve generates an electromagnetic force to be attracted on the plunger 11 'substantially in proportion to the current by energizing the proportional solenoid 24 by the above configuration, and causes the spool 5' to oppose the coil spring 26. , And the opening degree of the valve opening / closing portions 8,... Is proportionally controlled. At this time, since the attraction force of the proportional solenoid 24 is simply proportional to the magnitude of the current regardless of the displacement within the control range, the displacement of the spool 5 'is stable at a position where the force of the coil spring 26 and the electromagnetic force are balanced. And stop. Accordingly, under the bias of the proportional solenoid 24, the plurality of valve opening / closing portions 8, 8 move from P → A, B →
Allows T flow, has a direction switching function, and at the same time, electrically controls the valve passage flow rate as an analog quantity. The solenoid chamber 9 'is filled with a working liquid capable of flowing into and out of the return chamber 27', thereby giving a suitable viscous damping effect to the movable part of the proportional electromagnetic control valve.

[0003]

However, the proportional solenoid of the conventional proportional electromagnetic control valve needs to increase its suction force at a normal position where the suction gap is large, and can be effectively used in the effective control range. The attraction force was not always high, and the utilization efficiency of the electromagnetic force was not always good. In addition, the above-mentioned proportional solenoid requires a special shape for a part of the magnetic path, that is, a special magnetic path shape composed of a magnetic leakage portion and a cartridge non-permeable material portion, in order to obtain good proportional characteristics, which makes processing difficult and expensive. There was a disadvantage. Therefore, an object of the present invention is to use a simple solenoid having a suction force characteristic equivalent to a non-linear solenoid, that is, a normal on / off DC solenoid, in place of the proportional solenoid in order to effectively use the suction force generated by the solenoid. The current is controlled, and a non-linear spring characteristic is obtained by using a leaf spring instead of a coil spring to obtain a countermeasure, a proportional characteristic is obtained, and the maximum capacity (pressure × flow rate) of the control valve is increased at low cost. The object is to provide a proportional solenoid control valve.

[0004]

In order to achieve the above object, a proportional solenoid control valve of the present invention is basically provided with a valve chamber 2 'connected to a main line port 3, as shown in FIG. , A land 5, a spool 5 ′ having an annular groove 17, a coil spring 26 for holding the spool 5 ′ slidably fitted in the valve chamber 2 ′ in a normal position, The above coil spring 2 sandwiching the spool 5 '
In a proportional solenoid control valve provided with a proportional solenoid 24 opposing the non-linear solenoid 6, the non-linear solenoid 10 and the leaf spring 12 are opposed to each other with the spool 5 interposed therebetween.
2 is supported from behind by a seat of the non-linear spring support 13.

[0005]

In the above configuration, when the current of the nonlinear solenoid 10 is set to 0, the spool 5 is pulled back by the leaf spring 12 and maintains the normal position. At this time, the main pipeline ports 3,... Take a flow path communication form according to a spool type. Next, when the non-linear solenoid 10 is energized, the non-linear solenoid 10 generates a non-linear suction force corresponding to the current and the suction gap, and presses the central portion which is one end of the leaf spring 12 via the spool 5. Leaf spring 12
At the same time, the other end of the leaf spring 12 reduces its effective spring length while being in contact with the seat of the non-linear spring receiver 13, that is, the leaf spring 12 exhibits a non-linear spring characteristic. It displaces as if it were proportional to the current. Here, the suction force at a constant current value tends to increase as the suction gap becomes smaller, but since the rate of increase of the reaction force from the non-linear spring characteristic is larger, the displacement of the spool 5 is always controlled and stopped. .
That is, the nonlinear solenoid 10 has a simple structure, so that the flow in the valve opening / closing section can be electrically controlled as an analog amount as well as the efficiency of use of the electromagnetic force can be greatly increased. At the same time, the maximum capacity of the valve can be greatly increased. it can.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments. FIG. 1 shows a basic embodiment of a proportional electromagnetic control valve.
, That is, a main body 1 having a valve chamber 2 connected to the ports P, A, B, T, a spool 5 having lands 16,... And an annular groove 17, and the spool slidably fitted in the valve chamber 2. Leaf springs 12, 12 for holding 5 in a normal position
Non-linear spring receivers 13 and 13 for supporting the leaf springs 12 and 12 from behind, and non-linear solenoids opposed to the leaf springs 12 and 12 with the spool 5 interposed therebetween, that is, a normal on-off suction force characteristic. , The control chamber 6, the return chambers 27, 27 communicating with the return communication path 48, the valve opening / closing section 8,.
, 46, 46, and bolt 2, a pressure relief chamber 7, 7, which is partitioned from and communicates with a pressure relief communication passage 49, a pressure relief port 4 connected to the pressure relief communication passage 49.
0,... Each of the above constituent members 1, 2, 3, 5,
6, 8, 16, 17, 27, and 48 are points related to the configuration of the ports related to the main pipeline ports 3,... And the pressure release port 4, and further, the housing of the leaf springs 12 and 12 in the main body 1 and the solenoid Except for the points 10 and 10, which are the same as the conventional one described in FIG. 2, the same members are denoted by the same reference numerals and description thereof will be omitted. The bolt 20,
.. Fix the solenoid 10 enclosing the leaf spring 12 and the non-linear spring receiver 13 to the main body 1, and contact a portion connected to the center of one end of the leaf spring 12 with the end face of the main body 1. At the same time, the other end of the outer free end of the leaf spring 12 is brought into contact with the seat of the nonlinear spring receiver 13. The solenoid 10 is a push rod 34
Plunger 11 having cartridge and cartridge magnetically permeable member 3
0, a cartridge 18 having a cartridge impermeable material portion 19, a yoke 21 which is integrally brazed to the cartridge impermeable material portion 19 and has a hole for the push rod 34 in the center, and a yoke 21. The yoke 22, 23 for magnetically connecting the cartridge 21 and the cartridge magnetically permeable material portion 30, and the pressure release chamber which is sealed from the outside and formed by the cartridge 18, the yoke 21, the cover 15, and the O-ring 47. 7, a coil chamber 14, a terminal box 3 and a solenoid chamber 9.
7. The operation of the proportional electromagnetic control valve having the above configuration will be described below. When the current of the solenoids 10, 10 is 0, the spool 5 is pulled back by the leaf springs 12, 12 and holds the normal position. At this time, the main pipeline ports 3,... Take a flow path communication form according to a spool type.
Next, when one of the solenoids 10 is energized, the solenoid 10 generates a non-linear suction force corresponding to the current and the suction gap on the plunger 11, and the one leaf spring is formed via the push rod 34 and the spool 5. The central portion, which is one end of the spring 12, is pressed. At this time, the leaf spring 12 is deformed in an arched shape, and at the same time, the other end of the outer free end of the leaf spring 12 is in contact with the seat of one non-linear spring receiver 13 to reduce its effective spring length. That is, the leaf spring 12 has a non-linear spring characteristic, and after the balanced state, the spool 5 is displaced as if proportional to the current and stops. Here, the suction force at a constant current value tends to increase as the suction gap becomes smaller, but since the rate of increase in the reaction force from the nonlinear spring characteristic is larger, the displacement of the spool 5 is always controlled and stabilized. Stand still. In other words, the flow through the valve opening / closing portions 8,... (Tentatively P → A, B → T) is electrically analogized while effectively utilizing the suction force that can be generated by the solenoid by making the solenoid 10 a simple structure. At the same time, the maximum capacity of the valve can be greatly increased. The other solenoid 10
Is energized, the flow in the valve opening / closing section 8,...
B, A → T), but there is no difference from the other case of energizing. Further, the configuration of the ports related to the main pipeline ports 3,... May be two ports, and the number of the solenoids 10 may be one if necessary.

[0007]

As is apparent from the above description, the proportional solenoid control valve of the present invention makes the non-linear solenoid 10 and the leaf spring 12 oppose each other with the spool 5 interposed therebetween, and the non-linear spring Since it is supported at the seat of the receiver 13, the displacement of the spool can be proportionally controlled as an analog amount by a current by using a simple solenoid having a non-linear suction force characteristic. The maximum capacity of the valve can be greatly increased by effectively utilizing the available suction force.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a basic embodiment of a proportional electromagnetic control valve of the present invention.

FIG. 2 is a sectional view showing a conventional proportional electromagnetic control valve.

FIG. 3 is a sectional view showing a conventional proportional solenoid.

[Explanation of symbols]

1 ': body, 2': valve chamber, 3, 3 ... port for main pipeline, 5
... spool, 10 ... non-linear solenoid, 12 ... leaf spring,
13: Non-linear spring receiver, 16: Land, 17: Annular groove.

Claims (1)

[Claims] 1. A main body 1 'having a valve chamber 2' connected to a main conduit port 3, a land 16, and an annular groove 17.
, A coil spring 26 for holding the spool 5 ′ slidably fitted in the valve chamber 2 ′ in a normal position, and a proportional spring opposed to the coil spring 26 across the spool 5 ′. In the proportional electromagnetic control valve including the solenoid 24, the non-linear solenoid 10 and the leaf spring 12 are opposed to each other with the spool 5 interposed therebetween, and the leaf spring 12 is supported from behind by a seat of the non-linear spring receiver 13. Proportional solenoid control valve.