JP3909461B2 - Direct acting 2-port solenoid valve - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a direct acting two-port solenoid valve.
[0002]
[Prior art]
Supply port and output port of pressure fluid, valve seat in flow path connecting these ports, valve part having valve body for opening and closing the valve seat, excitation coil, fixed iron core, movable iron core and its return spring A direct-acting two-port solenoid valve in which the valve body that moves integrally with the movable iron core opens and closes the valve seat by energizing and releasing the excitation coil is already known without particular illustration. ing. The direct acting two-port solenoid valve can reduce the attractive force of the solenoid when the stroke of the movable iron core is reduced. Therefore, the solenoid can be made small and inexpensive, and this reduces power consumption. Therefore, the running cost can be reduced.
[0003]
The flow area of the direct acting two-port solenoid valve is πDh, where D is the flow path diameter of the valve seat and h is the stroke of the movable iron core that opens and closes the valve seat. In order to ensure the required flow path area, it is necessary to increase the flow path diameter D of the valve seat. However, when the flow path diameter of the valve seat is increased, the acting force of the fluid pressure on the inlet side that acts on the valve body that opens and closes the valve seat increases, and the valve body is pressed against the valve seat by this large force. The suction power must be increased.
[0004]
To solve this problem, as shown in FIGS. 3 and 4, a pressure fluid supply port P and an output port A, and a valve portion having a valve seat body 4 provided in a flow path connecting these ports. 2 and a solenoid 3 having an exciting coil 6 wound around a bobbin, a fixed iron core 7 and a plate-shaped movable iron core 8. By energizing the magnetizing coil 6 and releasing it, the movable iron core 8 is attached to the valve seat body 4. A direct acting two-port solenoid valve 1 for opening and closing a provided valve seat 5 is proposed in Japanese Utility Model Publication No. 3-48462.
As shown in detail in FIG. 4, the valve seat body 4 in the electromagnetic valve 1 includes peripheral walls 4 b,... Partitioned by a plurality of grooves 4 a, and bottomed recesses 4 c in these peripheral walls. The through-hole 4d which comprises the valve seat 5 is formed in each surrounding wall 4b.
In FIG. 3, reference numeral 7 a denotes a cushion member attached to the tip of the fixed iron core 7, and reference numeral 9 denotes a guide member that seals between the valve portion 2 and the solenoid 3 and guides the movement of the flat movable iron core 8. It is.
[0005]
Since this direct acting two-port solenoid valve 1 has a large passage diameter of the through hole 4d of the valve seat body 4, a desired passage area can be ensured even if the stroke of the movable iron core 8 is small, and the groove 4a. Since the acting force of the fluid pressure on the inlet side acting on the movable iron core 8 with the valve seat 5 closed is almost balanced by the fluid pressure on the inlet side flowing into the recess 4c from the bottom, the suction force of the solenoid 3 is reduced. be able to.
However, in the electromagnetic valve 1, the flow passage area of the valve seat 5 is reduced by the plurality of grooves 4a provided in the valve seat body 4, and the configuration of the valve seat 5 is complicated.
Further, since the flat movable iron core 8 is used, a known solenoid cannot be used as it is.
[0006]
[Problems to be solved by the invention]
The problem to be solved by the present invention is to provide a direct-acting two-port solenoid valve that has a simple valve seat structure and that can make the solenoid small and inexpensive.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, a direct-acting two-port solenoid valve according to the present invention includes a pressure fluid supply port and an output port, a valve seat in a flow path communicating these ports, and a valve body for opening and closing the valve seat. The valve body that moves integrally with the movable iron core opens and closes the valve seat by energizing the coil and releasing it. In the direct acting two-port solenoid valve, the valve section has an annular peripheral wall, a recess surrounded by the peripheral wall, a valve seat having an annular flow path formed in the peripheral wall, and an annular valve that opens and closes the flow path The movable iron core is provided with a balance passage for allowing the fluid on the inlet side to flow into the recess of the valve seat and the space between the fixed iron core and the movable iron core.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
1 and 2 show an embodiment of the present invention. This direct acting two-port solenoid valve 11 includes a valve portion 12 and a solenoid 13, which are airtightly connected by a set nut 14 attached to the solenoid 13. ing.
The valve body 15 of the valve part 12 includes a supply port P and an output port A for compressed air that are opened to the back and an opening on the solenoid 13 side, and a set nut 14 is screwed into the opening. A valve seat 16 is hermetically fitted in a flow path connecting these ports, and a valve seat 17 of the valve seat 16 is formed in an annular peripheral wall 18 and in the axial direction on the peripheral wall 18. The annular channel 19 and the bottomed recess 20 surrounded by the peripheral wall 18 are provided (see FIG. 2).
As shown in FIG. 1, the annular channel 19 is expanded in both the inner and outer directions on the output port A side, and a plurality of connecting portions 18a (two in the illustrated example) formed in the enlarged diameter portion 19a The inner part 18 and the outer part 18 are integrally connected.
[0009]
The solenoid 13 includes a bobbin 24 around which an exciting coil 23 is wound, magnetic frames 25 and 25 and a mold 26 that surround the bobbin 24, a fixed iron core 28 that is airtightly attached to a central hole of the bobbin 24, and a central hole of the bobbin 24. And a return spring 31 having a small urging force and contracted in a space 30 between these cores, and a fixing bolt 32 screwed to the fixed core 28 on the upper surface of the mold 26. A cover 33 is attached.
The movable iron core 29 is provided with a balance passage 34 that penetrates in the axial direction and communicates with the supply port P, and an annular valve body 21 that opens and closes the flow path 19 of the valve seat 17 from the supply port P side is secured to the tip. Yes.
Therefore, in a state in which the valve body 21 closes the flow path 19, the space 30 between the recess 20 and the iron core communicates with the supply port P through the balance passage 34 and the annular valve body 21.
A reference numeral 35 in FIG. 1 is a cushion member formed of a material having elasticity such as synthetic rubber, and reference numerals 36 and 36 are guide rings for guiding the movement of the movable iron core 29.
[0010]
In the above embodiment, when the energization of the exciting coil 23 is released and the valve body 21 closes the flow path 19 of the valve seat 17, the fluid in the supply port P flows between the balance passage 34 and the annular valve. Since the valve body 21 passes through the central portion of the body 21 and flows into the space 30 between the recess 20 and the iron core, the valve body 21 has an acting force of the inlet side fluid pressure acting on the opening of the flow path 19 and a return spring. The valve seat 17 is closed by a small force that is the sum of the urging force of 31.
When the exciting coil 23 is energized, the movable iron core 29 is attracted to the fixed iron core 28 and the valve body 21 opens the flow path 19 of the valve seat 17, so that the compressed air of the supply port P is output from the output port A. In this case, the suction force of the solenoid 13 is substantially balanced by the balance passage 34 and the annular valve body 21 because the acting force of the inlet side fluid pressure acting on the valve body 21 and the movable iron core 29 is balanced. It can be as small as slightly greater than the biasing force.
When energization of the exciting coil 23 is released, the movable iron core 29 and the valve body 21 are moved downward in the drawing by the urging force of the return spring 31 and the valve body 21 closes the flow path 19 of the valve seat 17. Communication of A is cut off.
[0011]
In the above embodiment, the flow passage diameter D of the valve seat 17 can be increased by making the flow passage 19 of the valve seat 17 annular, so that even if the stroke h of the valve body 21 and the movable iron core 29 is small, the necessary flow passage area can be increased. Can be secured. In this case, since the connecting portion 18a is provided in the enlarged diameter portion 19a of the flow channel, the flow channel area of the flow channel 19 is not reduced by the connecting portion 18a.
Further, since the acting force of the inlet side fluid pressure acting on the movable iron core 29 and the valve body 21 is substantially balanced by the balance passage 34 and the annular valve body 21, the suction force of the solenoid 13 can be reduced. Coupled with the small stroke h of the movable iron core 29, the solenoid 13 can be made small and inexpensive, and the power consumption is reduced, so that the running cost can be reduced.
Further, since it is not necessary to provide a groove in the peripheral wall 18 of the valve seat body 16, the configuration is simple, and a known solenoid can be used as it is except that the movable iron core 29 has a balance passage 34. it can.
[0012]
【The invention's effect】
The direct acting two-port solenoid valve of the present invention has an annular flow passage in the valve seat and a large passage diameter, and the inlet side fluid pressure acting on the movable iron core and the valve body by the balance passage formed in the movable iron core. Because the acting force is almost balanced, the required flow passage area can be secured even if the stroke of the movable iron core is reduced, and the suction force of the solenoid is reduced, making it small and inexpensive. In addition, since the power consumption is low, the running cost can be reduced.
Further, since the balance passage is provided in the movable iron core, the flow passage area of the valve seat is not reduced, and the valve seat can be easily formed.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional front view of an embodiment.
FIG. 2 is a perspective view of the same valve seat body.
FIG. 3 is a longitudinal front view of a previously proposed solenoid valve.
FIG. 4 is a perspective view of the valve seat body.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 Solenoid valve 12 Valve part 13 Solenoid 17 Valve seat 18 Perimeter wall 19 Flow path 20 Recess 21 Valve body 23 Excitation coil 28 Fixed iron core 29 Movable iron core 30 Space 31 Return spring 34 Balance passage P, A Port

Claims (1)

Supply port and output port of pressure fluid, valve seat in flow path connecting these ports, valve part having valve body for opening and closing the valve seat, excitation coil, fixed iron core, movable iron core and its return spring A direct-acting two-port solenoid valve in which the valve element that moves integrally with the movable iron core opens and closes the valve seat by energizing and releasing the exciting coil.
The valve portion includes an annular peripheral wall, a recess surrounded by the peripheral wall, a valve seat having an annular flow path formed in the peripheral wall, and an annular valve body for opening and closing the flow path,
The movable iron core includes a balance passage that allows the fluid on the inlet side to flow into the recess of the valve seat and the space between the fixed iron core and the movable iron core.
This is a direct acting 2-port solenoid valve.

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