JPH0535313B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a directional control valve that controls fluid flow by electromagnetic operating force, mechanical operating force, or fluid pressure operating force.

(Prior Art and Problems) Conventionally, poppet valves such as those disclosed in Japanese Utility Model Application No. 54-87434 have been known as such directional control valves. However, in this structure, the poppet 21 that performs the sealing action is formed on the conical surface 20, so if a multi-way valve such as a four-way valve is constructed using only such a poppet valve, multiple conical surfaces may seal simultaneously. and therefore multiple conical surfaces
Since it is necessary to accurately configure the dimensions between 20 and 20, it is practically difficult to manufacture, so this
As shown in No. 87434, one valve part is a spool 23 having a cylindrical surface 22, and the spool valve is sealed with the valve seat 9, and a composite structure with a poppet valve is used to achieve a multi-way valve. In addition, these directional valves have recently become increasingly smaller, and are increasingly being used in the semiconductor field, which is referred to as a high-tech industry. For this reason, as a compact directional control valve for semiconductor manufacturing equipment, it is required to be able to flow a large flow rate and operate a large actuator, as well as to be able to easily handle exhaust gas after long-term use without lubrication.

In this respect, Utility Model Application Publication No. 54-87434 has a sliding portion as a spool valve, and is configured so that the sliding shaft 16 with gaskets 19 provided on both ends slides inside the presser fitting 13. . In other words, since it has sliding parts and uses gaskets, it is impossible to use it without lubrication, and even if it were to be used without lubrication, its durability would be extremely shortened, and furthermore, Oil, moisture, etc. contained in the exhaust gas pose an environmental problem, so in order to centralize the exhaust gas into one, it is necessary to create a passage that connects exhaust ports 4 and 6 as a multi-way valve. must be provided inside the base 1, and there is not enough room in the shape of a small valve, and even if a communicating passage is provided inside the base 1, the pressure balance due to the exhaust pressure will not be maintained and the valve will not operate properly. was unstable. In addition, as a multi-way valve with no sliding parts,
A four-way valve consisting of two independent poppet valves, such as No. 56-5874, is known, but this structure has no sliding parts, so it can be used without lubrication. Although it is possible to reduce the size in the longitudinal direction compared to the multi-way valve shown in the above-mentioned Utility Model Application Publication No. 87434/1987, which has a composite structure of a spool valve and a poppet valve, it is possible to reduce the size in the longitudinal direction. Since the pressure when the first valve element is switched is applied as pilot pressure to the pressing mechanism of the second valve element to switch the second valve element, a difference occurs in the switching operation of the two valve elements. I end up. That is, since it takes more time to switch the second valve element after the solenoid is turned on than the first valve element, the operation is delayed accordingly when the actuator is connected and operated. This problem becomes more pronounced as the capacity of the actuator increases, resulting in drawbacks such as a longer cycle time. This can sometimes become a fatal drawback when mass-producing semiconductor manufacturing equipment.

(Technical Problems to be Solved) An object of the present invention is to obtain a small-sized directional control valve that can be used for a long time without lubrication, has easy exhaust treatment, and has stable valve operation.

(Structure of the Invention) The technical means taken to solve the above technical problem is to construct a multi-way valve using only a poppet valve, and further provide a communication passage in the movable member constituting the poppet valve to provide an exhaust passage. This is because it has been configured to be connected.

(Embodiments of the Invention) Hereinafter, embodiments in which the present invention is applied to an electromagnetic directional control valve will be described with reference to FIGS. 1 and 2.

As shown in FIG. 1, the directional control valve of the present invention is composed of a main valve part V and an electromagnet part M. The main valve part V is composed of a valve body 1 and a valve part 2 built into the valve body 1. and a base 3 attached to the lower part of the valve body 1. The valve body 1 has a guide hole 11 passing through the center in the longitudinal direction, and large-diameter counterbore holes 12 and 13 concentrically extending from both end faces of the guide hole 11. Annular valve seat 1
4 and 15 are formed protrudingly. A plurality of ports, ie, a supply port P, two connection ports A, B, and two exhaust ports R1, R2 are formed to penetrate from the lower surface of the valve body 1 into the guide hole 11 and counterbore holes 12, 13. It serves as an opening for a four-way valve. The valve part 2 built into the valve body having the above structure is slidably fitted into the guide hole 11 of the valve body 1, and the shaft part 21 having the through hole 21a to the internal axis is press-fitted into both sides of the shaft part 21. It has poppets 22, 23 formed by the valve body 1, and valve seat bodies 24 and 25 which are screwed into the counterbore holes 12, 13 of the valve body 1 and fixed at a predetermined position. Valve body 1
The valve seats 22a, 22b and 23a, 23b are disposed in the counterbore holes 12, 13 of the valves, and have sealing materials such as rubber attached to annular grooves on both end faces by baking or the like. The valve seat bodies 24 and 25 have annular valve seats 24a and 25a protruding from their front end faces, and perform a valve action with the valve seats of the poppets 22 and 23. Further, a shaft portion 2 constituting the valve portion 2
As shown in FIG. 2, four grooves 21b are formed at equal intervals in the axial direction on the outer periphery of the tube 1 to form a fluid passage. The valve seat bodies 24 and 25 each have an O-ring 9a, 9b attached to one location on the outer periphery, and holes 24b and 25b communicating from the annular valve seat side to the outer periphery side.
and are connected to exhaust ports R1 and R2, respectively. Further, a compression spring 6 is stretched between the end surface of the poppet 22 on the side of the valve seat 22a and the valve seat body 24, and presses the valve portion 2 in one direction. Due to the above structure, the poppet 22 side constitutes the first valve, and the poppet 23 side constitutes the second valve. The base 3 has ports connected to the ports P, A, B, R1, and R2 of the valve body 1 on its upper surface, and one opening on the side surface thereof. Note that R1 and R
2, only one of them is opened depending on the installation state, and this base 3 is fixed to the valve body 1 via a packing 7 with screws or the like (not shown). The through hole 21a of the shaft portion 21 described above is effective not only for communicating and making the two exhaust ports common, but also for balancing the pressure in the valve portion as described later.

In the above, the valve seat 22 of the poppet 22
a, 22b, the annular valve seat 24a of the valve seat body 24, and the annular valve seat 14 of the valve body 1 constitute a first valve part, and the valve seats 23a, 22b of the poppet 23,
23b, the annular valve seat 25a of the valve seat body 25, and the annular valve seat 15 of the valve body 1 constitute a second valve portion.

Next, to explain the electromagnet part M, this electromagnet part M shows a DC solenoid, and includes a lower yoke 100 attached to one end surface of the valve body 1 and an outer cylindrical yoke 1 holding a coil 101 inside.
02, an upper yoke 103 located at the end, a movable core 104 that is a driving member inserted into the coil, and a fixed core 105 that is adjustable to the upper yoke 103 and that the movable core 104 collides with. It is something that The tip of the movable iron core 104 is connected to the valve seat 23b of the poppet 23 of the valve portion 2.
It is pressed against the side end surface by a compression spring 8. The force of the compression spring 8 is set to be larger than the force of the compression spring 6. Therefore, the valve part 2 is located at the left position in FIG. It also communicates with the mouth R1. The fixed core 105 is directly screwed to the upper yoke 103, and the solenoid stroke can be adjusted by turning the fixed core 105 with a spanner or the like. Numbers 9a and 9b in the diagram
is an O-ring.

The operation of this embodiment configured as above will be explained.

FIG. 1 shows the non-energized state, and as mentioned above, the valve portion 2 is in the left position due to the force of the compression spring 8, and the valve seat 22a of the poppet 22 is in the valve seat body 24.
The valve seat 23a of the poppet 23 contacts the annular valve seat 15 of the valve body 1, and the supply port P communicates from the fluid passage 21b to the connection port A, while the connection port B It communicates with the exhaust port R2 and further communicates with the exhaust port R1 via the through hole 21a. Therefore, pressure fluid from the supply port P flows into an actuator (not shown) such as a cylinder from the connection port A, and exhaust from the actuator flows from the connection port B through the counterbore hole 13 of the valve body 1 to the exhaust port. R2
At the same time, it is also discharged from the opposite side exhaust port R1 through the through hole 21a of the shaft portion 21.

Next, when the solenoid coil 101 is energized, the movable core 104 is attracted toward the fixed core by electromagnetic force against the compression spring 8 . Therefore, this time valve part 2
is moved to the right in the figure by the force of the compression spring 6, and the valve seat 22b of the poppet 22 is moved to the annular valve seat 1 of the valve body 1.
4 and the valve seat 23b of the poppet 23
contacts the annular valve seat 25a of the valve seat body 25, and the supply port P communicates with the connection port B from the fluid passage 21b, while the connection port A communicates with the exhaust port R1. Therefore, the pressure fluid from the supply port P flows into an actuator (not shown) such as a cylinder from the connection port B, and the exhaust from the actuator is discharged from the connection port A through the counterbore hole in the valve body 1 as described above. 12 and also flows into the counterbore 13 on the opposite side through the through hole 21a of the shaft portion 21, and then the exhaust port R2.
Otherwise, it will flow out to the exhaust port R2. Therefore, the exhaust from the actuator flows into both sides of the counterbore holes (12, 13) serving as valve chambers and acts on the poppet valve, so no force is generated in the poppet valve in the axial direction, that is, in the switching direction. , exhibiting a pressure balance state.

In the figure, the fluid passage 21b is formed in the shaft portion, but it can be similarly formed in the valve body side.

Further, in the embodiment, the configuration is such that two exhaust vents are selected on the base 3 side, but the holes 24b and 25b formed in the valve seat bodies 24 and 25 are selectively formed. Therefore, it is possible to similarly implement the configuration in which two exhaust vents are selected.

In the embodiment, the movable core 104 of a DC solenoid is used as the driving member of a directional valve that controls fluid flow using electromagnetic operating force. However, when using mechanical operating force, a lever or the like may be used. In the case of using the operating force of fluid pressure, the same can be achieved by using a pilot piston as the driving member.

(Effects of the Invention) As explained above, since the present invention constitutes a multi-way valve using only a poppet valve, there is no sliding part caused by the packing during valve operation, and therefore no lubricating oil is required. In addition to enabling long-term use, a through hole is provided in the movable member that constitutes the poppet valve to communicate the exhaust passage, making exhaust treatment easier as it can be gathered in one place.
Since the pressures are balanced between the first valve part and the second valve part, the valve can operate more smoothly and the valve can be switched with a smaller operating force, which is expected to bring about the unique and excellent effects of the present invention. At the same time, although the valve seat is small in size, the diameter of the valve seat is larger than that of the port, so a larger flow rate can be flowed with a smaller stroke and a larger actuator can be operated. Further, since the first valve seat and the second valve portion are integrated at the shaft portion, there is no delay in operation, and it is possible to provide a switching valve that eliminates the drawbacks of the conventional example.

Furthermore, in the present invention, the shaft portion of the movable member is slidably fitted into the guide hole provided in the valve body. For example, Kimiaki Sane
52-35541, when a movable member is guided through a through hole formed in a member screwed to the valve body such as a valve seat body, the machining accuracy and assembly accuracy of the screw may be affected by fluctuations in the movement of the axis of the movable member. In contrast, guiding only through the guide hole in the valve body can ensure that the axes of the poppet and valve seat are aligned, and the valve can be operated stably. Furthermore, since the end face of the poppet is flat, even if the poppet is slightly eccentric with respect to the valve seat, the sealing performance will not be affected.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view showing an example of a directional control valve according to the present invention, and FIG. 2 is a sectional view taken along line XX in FIG. (Explanation of symbols), V... Main valve part, M... Electromagnet part, 1... Valve body, 11... Guide hole, 12, 13
...Counterbore, 14,15...Annular valve seat, 2...
Valve part, 21...Shaft part, 21a...Through hole, 22,
23...Poppet, 22a, 22b, 23a, 2
3b... Valve seat, 24, 25... Valve seat body, 24
a, 25a... annular valve seat, 24b, 25b...
Hole, 3... Base, 4, 5... O-ring, 6, 8...
...Compression spring, 7...Packskin, 9a, 9b...O
Ring, 100...lower yoke, 101...coil, 102...outer cylinder yoke, 103...upper yoke, 104...movable core, 105...fixed core.

Claims (1)

[Scope of Claims] 1. In a directional control valve that controls fluid flow by electromagnetic operating force, mechanical operating force, or fluid pressure operating force, a large-diameter counterbore drilled from both sides and having a guide hole passing through it. A valve body having an annular valve seat formed on the bottom surface of the hole, and a supply port penetrating from one side of the outside to the guide hole and the counterbore hole, a plurality of connection ports, and an exhaust port, and a valve body that slides into the guide hole and extends inside. A movable member having a valve seat fixed to both end faces and a poppet with a flat end face fixed to each side of the shaft portion having a through hole, and a movable member fixed to the two counterbore holes so as to be adjustable in the axial direction, and a front end face. a valve seat body that forms an annular valve seat and constitutes a first valve part and a second valve part, respectively, between the annular valve seat, the valve body, and the valve seat; and a drive that presses one end of the movable member. A poppet-shaped direction characterized in that a multi-way poppet valve is constructed from the member, and an exhaust passage is communicated with the through hole of the shaft part to balance the pressure between the first valve part and the second valve part. switching valve. 2. The directional control valve according to claim 1, wherein a plurality of axial fluid passage grooves are formed on the outer periphery of the shaft portion that slides into the guide hole. 3. The directional control valve according to claim 1, wherein a plurality of axial fluid passage grooves are formed on the inner periphery of the guide hole into which the shaft portion slides. 4. The directional control valve according to claim 1, wherein only one of the plurality of exhaust ports formed in the valve body is communicated with the shaft through hole of the movable member via the valve seat body.