JPH07208635A - Electromagnet for electromagnetic type air control valve - Google Patents

Abstract

PURPOSE:TO provide an electromagnet for an electromagnetic type air control valve by which the shock of a movable iron core, when attracted, is decreased and the movable iron core is given high durability to deformation and wear. CONSTITUTION:An electromagnet 40 for an electromagnetic type air control valve comprises an air control valve 10 which provide a poppet valve 23 with a through-hole 24 and opens/closes a flow passage 14 by the operation of compressed air force and spring force on a diaphragm 21 with a throttle hole 22 and an electromagnet 40 which closes the through-hole 24 by the normal energization of a return spring 59 and provides a movable iron core 55 to have contact with a fixed magnetic pole 45 after attracted by the electrification of an exciting coil 41 and moved to the axial direction and possible to open the through-hole 24. A shock absorber 60 which is supported by an elastic body 65 in a backward movable manner is protruded on one of the mutual contact faces 46, 57 of the fixed magnetic pole 45 and the movable iron core 55.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnet for an electromagnetic air control valve having a plunger type movable iron core.

[0002]

2. Description of the Related Art Conventionally, an electromagnet for a solenoid type pneumatic control valve having a plunger type movable iron core has a fixed magnetic pole and a movable magnetic pole which are disposed inside the exciting coil so as to be opposed to each other on the same axis line. However, the through hole of the poppet valve provided in the diaphragm of the air control valve is formed so as to be openable and closable, and the abutting surfaces of the fixed magnetic pole and the movable magnetic pole which face each other are generally formed in a plane shape orthogonal to the axis. .

The movable iron core is moved in the axial direction by being guided by a bobbin around which the exciting coil is wound. When the exciting coil is not energized, it is urged by a return spring to move away from the fixed magnetic pole, and one end surface of the movable iron core is The through hole is closed, and the contact surface is brought into contact with the fixed magnetic pole by energization, and one end surface is separated from the through hole to open the opening.

[0004]

However, in the electromagnet for the electromagnetic type air control valve having such a conventional structure, the movable iron core moves forward due to the magnetic attraction force generated by the energization of the exciting coil to impact the fixed magnetic pole. It comes into contact and is adsorbed. Therefore, when the number of times of adsorption is increased, the contact surface of the movable iron core is deformed and worn (so-called so-called sagging phenomenon), and the suction interval (the distance between the contact surfaces of the fixed magnetic pole and the movable magnetic pole when de-energized) increases. However, there was a problem that the suction power declined. Further, the deformation of the contact surface of the movable iron core appears as an annular protrusion in the radial direction, and the protrusion rubs against the inner wall of the bobbin of the exciting coil, hindering the smooth operation of the movable iron core. .

The present invention has been made in view of the above, and an object thereof is to reduce the impact at the time of attracting a movable iron core and to have a high durability against deformation and wear of the movable iron core. It is intended to provide an electromagnet for an air control valve.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above object, and is provided with a poppet valve having a through hole and a compressed air force and a spring force acting on a diaphragm having a throttle hole. An air control valve that opens and closes the flow path and a return spring constantly closes the through hole, is attracted by energization of the exciting coil, moves in the axial direction, contacts the fixed magnetic pole, and opens the through hole. An electromagnet for an electromagnetic air control valve, comprising: an electromagnet having a movable iron core that is capable of moving, and an electromagnet that is retractably supported by an elastic body on at least one of the mutual contact surfaces of the fixed magnetic pole and the movable iron core. An electromagnet for an electromagnetic air control valve, characterized in that a shock absorber is provided in a protruding manner.

[0007]

The present invention is configured as described above, and when the exciting coil of the electromagnet for the electromagnetic air control valve is energized, the movable iron core is attracted toward the fixed magnetic pole, and the contact surface between them is Abuts and opens the through hole of the air control valve.

At this time, the projecting portion of the cushioning body first comes into contact with the other side to soften the impact when the movable iron core is adsorbed, and retracts to compress the elastic body to absorb the impact. This reduces the impact of attraction of the movable core to the fixed magnetic pole.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an electromagnet for an electromagnetic air control valve according to the present invention will be described below with reference to the drawings.

In the figure, an electromagnetic type air control valve indicated by reference numeral 1 applies a compressed air force and a spring force to a diaphragm 21 having a poppet valve 23 having a through hole 24 to apply a compressed air force and a spring force.
The air control valve 10 for opening and closing 4, and the return spring 59 normally closes the through hole 24, is attracted by the energization of the exciting coil 41 and moves in the axial direction to abut the fixed magnetic pole 45 and the through hole. The electromagnet 40 is provided with a movable iron core 55 capable of opening 24, and the electromagnet 40 has a cushioning member 60 projecting from a contact surface 57 of the movable iron core 55 so as to be retractable by an elastic body 65. Is configured.

The air control valve 10 includes a valve housing 11 and
The base portion 30 and the main valve body 20 and the like interposed between the two are formed. The valve housing 11 is provided with a flow passage 14 having an inflow port 12 at one end and an outflow port 13 at the other end, and a valve seat 15 shown upward in FIG. 1 is provided in the middle of the flow passage 14. The base portion 30 is formed to have a concave upper chamber 31 and a connecting portion 35 having a hole in which the movable iron core 55 is movable and to which the electromagnet 40 is attached. Is provided with a stopper portion 33 that defines the upward movement position of the.

The main valve body 20 has a diaphragm 21 having a throttle hole 22 at a predetermined position, and a through hole 2 penetrating vertically.
4 and a poppet valve 23 attached to the center of the diaphragm 21 by a flange 26. An upper end opening of the through hole 24 of the poppet valve 23 is formed so as to be capable of being closed by a closing member 67 which will be described later, and a lower portion of the poppet valve 23 is brought into contact with the valve seat 15 to be closed and flow therethrough. The passage 14 is provided so as to be shut off.

The electromagnet 40 includes an exciting coil 41, a fixed iron core 44, and a buffer member 6 supported by an elastic member 65 so as to be retractable.
And a movable iron core 55 equipped with 0.

The exciting coil 41 is wound around a cylindrical bobbin 43, and is formed so that an exciting current is supplied by a power supply line 42. The fixed iron core 44 includes a fixed magnetic pole 45, a rear iron core 47, and a front iron core 4 each made of a magnetic material.
8, a connecting member 49, and a case-shaped main body 50 that houses the exciting coil 41.

The fixed magnetic pole 45 is formed in a round bar shape, and the upper end side thereof is integrally fixed to the rear iron core 47 and the main body 50 in FIG. The fixed magnetic pole 45 is
A flat contact surface 46 that is orthogonal to the axis is formed on the lower end side, and is closely fitted inside the bobbin 43, in the embodiment, a cylindrical body 52 provided inside the bobbin 43. There is. The tubular body 52 is made of a non-magnetic material, and the lower end side thereof has the front iron core 48 and the connecting member 49.
Is provided to penetrate. Further, the contact surface 46 is provided with a bear removing coil 53.

The movable iron core 55 is made of a magnetic material in the shape of a round bar, has a step hole 56 penetrating in the axial direction, and is provided movably in the axial direction in the tubular body 52 and the connecting portion 35. . A flat contact surface 57 orthogonal to the axis is formed on the upper end side of the movable iron core 55, a small diameter portion 56a of a step hole 56 is formed in the center of the contact surface 57, and a lower end side central portion thereof is formed. A large diameter portion (not shown) of the step hole 56 is formed as an opening.

An annular locking portion 58 is formed on the outer periphery of the lower end of the movable iron core 55, and the locking portion 58 and the connecting member 49 are formed.
By the return spring 59 interposed between the movable iron core 55 and
Are always biased in the backward direction (downward in FIG. 1).
Then, in the step hole 56, the cushioning body 60 and the elastic body 65 are arranged, and the closing member 67 is fixed.

The shock absorber 60 is made of a rubber-like elastic material such as NBR and has a hardness of JISA (H _S ) 70 in the embodiment and has a diameter allowing loose insertion into the small diameter portion 56a of the step hole 56. However, it is formed to have a slightly large-diameter base portion 61 that defines the protruding length from the contact surface 57. When the base portion 61 is inserted into the small-diameter portion 56a, the base portion 61 engages with the stepped portion of the small-diameter portion 56a, and the tip portion 62 is formed in a protruding position slightly protruding from the contact surface 57.

The elastic body 65, which is a compression coil spring in the embodiment, is interposed between the cushioning body 60 and the closing member 67, and is formed so as to always urge the cushioning body 60 in the protruding position direction. There is. As shown in FIG. 4, the spring load A of the elastic body 65 is set in the range of 70 to 80% of the attraction force of the movable iron core 55 in the electromagnet 40, considering the stroke of the movable iron core 55 and the attraction force. Is preferred.

The closing member 67 is made of a rubber-like elastic material such as NBR and is fixed to the large diameter portion of the movable iron core 55 by a pin. Then, it abuts on the upper portion of the main valve body 20 to define the retracted end of the movable iron core 55 (when the poppet valve 23 closes the valve seat 15), and the opening of the through hole 24 is moved along with the movement of the movable iron core 55. It is formed so that it can be opened and closed.

In this electromagnet 40, an O-ring (not shown in the figure) is interposed, and a connecting member 49 has a connecting portion 3 of the base portion 30.
It is screwed to 5 and is integrally attached to the air control valve 10. At this time, the fixed magnetic pole 45, the cylindrical body 52, the connecting member 4
The inside of 9 forms a pressure vessel communicating with the upper chamber 31.

Next, the operation of the electromagnetic air control valve 1 thus constructed will be described.

In the electromagnetic type air control valve 1, the inflow port 12 and the outflow port 13 of the air control valve 10 are connected to a compressed air circuit (not shown), and the power supply line 42 of the electromagnet 40 is electrically connected to the operation panel. To be done.

When de-energized, the movable iron core 55 of the electromagnet 40 is
Is retracted by being biased by the return spring 59, and the shock absorber 60 is
The elastic body 65 is biased to the projecting position, the tip portion 62 thereof is separated from the contact surface 46 of the fixed magnetic pole 45, and the closing member 67 is brought into contact with the upper end portion of the poppet valve 23 to penetrate the through hole 24. Is blocked. At this time, the compressed air from the inflow port 12 flows into the upper chamber 31 through the throttle hole 22 of the diaphragm 21, and the main valve body 20 causes the acting force based on the compressed air flowing into the upper chamber 31 and the return spring 59. Due to the urging force, it is pressed downward against the acting force based on the compressed air acting on the lower surface of the diaphragm 21, and the poppet valve 23 is seated on the valve seat 15 to block the flow passage 14 (see FIG. 1). ).

When the exciting coil 41 of the electromagnet 40 is energized, magnetic flux is generated in the magnetic circuit formed by the fixed magnetic pole 45 of the fixed iron core 44, the rear iron core 47, the front iron core 48, the connecting member 49, the main body 50, and the movable iron core 55. Occurred and movable iron core 55
The attraction force acts on the fixed magnetic pole 45. As a result, the movable iron core 55 is attracted, and rapidly moves forward against the urging force of the return spring 59 (upward direction in FIG. 1). First, the tip end portion 62 of the shock absorber 60 is brought into contact with the contact surface 46 of the fixed magnetic pole 45. Abut.

At this time, the impact due to the suction operation of the movable iron core 55 is softened by the rubber-like elasticity of the buffer 60, and the buffer 60 is pressed downward in FIG. Due to this pressing force, the buffer body 60 is pressed downward relative to the movable iron core 55, and the elastic body 65 is compressed. During this time, the movable iron core 55 moves forward while the operating impact force due to the suction is reduced, and finally the tip 62 surface of the buffer 60 and the contact surface 57 of the movable iron core 55 are flush with each other. It contacts the contact surface 46 of the fixed magnetic pole 45. In this way, the abutment surface 57 abuts the abutment surface 46 without impact and is adsorbed.

On the other hand, the suction operation of the movable iron core 55 causes the closing member 67 to separate from the upper portion of the main valve body 20 to open the through hole 24 (see FIG. 2). As a result, the compressed air in the upper chamber 31 flows out from the through hole 24 into the flow path 14 on the outlet 13 side, and the pressure in the upper chamber 31 is reduced by the throttling action of the throttling hole 22. Then, the main valve body 20 has a diaphragm 21.
The acting force based on the pressure difference between the pressure acting on the lower surface and the pressure inside the upper chamber 31 causes the flange 26 to come into contact with the stopper portion 33 and stop by moving away from the valve seat 15 and moving upward. The inlet 12 and the outlet 13 are connected (see FIG. 3). The movement of the main valve body 20 is restricted by the stopper portion 33 so that the movable iron core 55 and the fixed magnetic pole 45 are not impacted by the movement of the main valve body 20.

When the excitation coil 11 is de-energized from the state shown in FIG. 3, the magnetic flux, that is, the attractive force of the movable iron core 55 disappears. As a result, the movable iron core 55 is retracted by the urging force of the return spring 59, and the closing member 67 closes the upper end opening of the through hole 12. Further, the pressure difference acting on the upper chamber 31 and the lower surface of the diaphragm 21 disappears, the main valve body 20 moves downward together with the movable iron core 55, closes the valve seat 15, and returns to the state of FIG.

In order to confirm the effect of the above embodiment, FIGS.
As shown in, a movable iron core 55A (conventional equivalent product) made of a solid magnetic material having the same diameter d and length h as the movable iron core 55 was prepared, and a durability comparison test was conducted. The test is a fixed magnetic pole 4
Deformation and wear P of the respective contact surfaces 57, 57A due to repeated adsorption of the movable iron cores 55, 55A onto the
The comparison is made by the change of the length h.

FIG. 7 is a curve diagram in which the number of times of adsorption is plotted on the horizontal axis and the change in diameter d is plotted on the vertical axis. The solid line represents the movable iron core 55 equipped with the cushioning body 60 and the elastic body 65 of the present invention. The broken line represents the movable iron core 55A of a conventional equivalent product. As shown in the figure, the movable iron core 55A has a diameter d that increases rapidly with each increase in the number of times of adsorption. The smooth suction operation can be performed for a very long period of time while maintaining the smooth movement of the.

FIG. 8 is a curve diagram in which the horizontal axis represents the number of times of adsorption and the vertical axis represents the change in the length h. Similarly, the movable iron core 55 equipped with the buffer 60 and the elastic body 65 is represented by a solid line, The movable core 55A of a conventional equivalent product is indicated by a broken line. As shown in the figure, the decrease in the length h of the movable iron core 55A is extremely large.
The length h decreases very little. Therefore, the change in the suction interval is small, an appropriate suction force can be maintained for a long period of time, and accurate suction can be performed.

The present invention is not limited to the above description and the illustrated examples, and its embodiment can be modified without departing from the technical idea of the present invention. For example, the fixed magnetic pole 45 may be provided with the cushioning body 60 and the elastic body 65, and the tip portion 62 of the cushioning body 60 may be provided so as to project from the contact surface 46. In addition, the cushioning body and the elastic body may be symmetrically provided in the movable iron core and the fixed magnetic pole, respectively. Further, the elastic body may be a rubber-like elastic body that is softer than the cushioning body, or may be an air spring formed by compressing sealed air between the cushioning body and the stopper.

[0033]

As described above, according to the electromagnet for an electromagnetic air control valve of the present invention, when the movable iron core is attracted, the protruding portion of the buffer body first comes into contact with the contact surface on the other side. Absorbs the impact shock and compresses the elastic body to retreat,
Can absorb shock.

Therefore, the impact of attraction of the movable core to the fixed magnetic pole is reduced, and the contact surface of the movable core is prevented from being deformed or worn.
It can operate accurately and smoothly over a long period of time and has high durability.

Further, since the adsorption shock of the movable iron core can be alleviated, the operation noise of the electromagnet for the electromagnetic air control valve can be reduced and the operation can be performed with low vibration.

[Brief description of drawings]

FIG. 1 is a side sectional view of an electromagnet for an electromagnetic air control valve according to an embodiment of the present invention.

FIG. 2 is a side sectional view of the electromagnetic air control valve showing a state immediately after energization.

FIG. 3 is a side sectional view of the electromagnetic type air control valve in the same energized state.

FIG. 4 is a curve diagram showing the relationship between the attraction force of an electromagnet and the spring load of an elastic body.

FIG. 5 is a schematic diagram illustrating a movable iron core of the electromagnet of the present invention and its deformation and wear.

FIG. 6 is a schematic diagram for explaining a movable core of an electromagnet of a conventional equivalent product and its deformation and wear.

FIG. 7 is a curve diagram showing changes in diameter d in a durability comparison test.

FIG. 8 is a curve diagram showing a change in the length h.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electromagnetic air control valve 10 Air control valve 14 Flow path 20 Main valve body 21 Diaphragm 23 Poppet valve 24 Through hole 40 Electromagnet 41 Excitation coil 44 Fixed iron core 45 Fixed magnetic pole 46 Abutting surface 55 Movable iron core 57 Abutting surface 60 Buffer 65 elastic body 67 closing member

Claims (1)

[Claims] 1. An air control valve having a poppet valve having a through hole and opening and closing a flow passage by applying a compressed air force and a spring force to a diaphragm having a throttle hole, and a return spring normally biased by the return spring. An electromagnet for an electromagnetic air control valve, comprising: an electromagnet having a movable iron core that closes the through hole, is attracted by energization of an exciting coil, moves in the axial direction, contacts the fixed magnetic pole, and can open the through hole. The electromagnetic air control valve is characterized in that at least one of the abutting surfaces of the fixed magnetic pole and the movable iron core is provided with a buffer body projectingly supported by an elastic body so as to be retractable. Electromagnet.