JPS61206879A - Electromagnetic type flow-rate control valve - Google Patents

Abstract

PURPOSE:To improve the static and dynamic characteristics by installing a driving means by allowing a buffer member consisting of rubber elastic sheets to be opposed to a throttle adjusting plate and projecting the edge surface in the direction of axis line from the edge surface of the driving means opposed to a throttle adjusting plate. CONSTITUTION:A casing 10 for supporting an electromagnet 5 has an opened port on the edge surface opposed to a throttle adjusting plate 4 and accommodates a buffer member 12 made of rubber elastic material into said opened port. The edge surface of the buffer member 12 projects in the direction of axis line so that the throttle adjusting plate 4 does not directly contact with the edge surface of the casing 10, when the throttle adjusting plate 4 allows a valve piece 3 to perfectly contact with a valve seat 2a. Therefore, even if the valve body 3 is pressed in the direction of valve seat by deflecting the throttle adjusting plate 4 in the direction of valve seat, and the throttle adjusting plate 4 does not shift, deflecting from the direction of the axis line, since the movable body 3 contacts with the buffer member 12 on the peripheral edge part of the adjusting plate 4, and the vibration around the valve body 3 can be suppressed.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a flow control valve used in a circuit to move fluid equipment as intended, and in particular, to shift a valve body toward a valve seat as necessary. This invention relates to an electromagnetic flow control valve that can control force and continuously change flow rate or pressure.

(Prior art) A flow control valve is used to adjust the flow rate of a fluid circuit, adjust the movement speed of an actuator, and adjust the rate of pressure rise. , fine adjustment is possible, and stable and continuous characteristics are required.

The most common type is a needle valve. This uses a screw to advance or retreat a needle valve with a conical tip to change the valve opening. However, it has many problems due to its structure. It is difficult to eliminate play in the threaded part, misalignment of the axes of the orifice and needle valve, etc., and the change in screw rotation and valve opening are inconsistent, making it impossible to accurately adjust the flow rate or pressure. There was a drawback. In addition, wear of the threaded portion was also a major problem.

On the other hand, as a flow control valve developed to solve the above-mentioned mechanical problem, there is a valve shown in FIG. 3(a), for example.

In this valve, a valve seat member 2 having a valve seat 2a having a substantially conical inner surface is fixed to a pressurized fluid inlet 1a of a housing 1, and a valve body 3 that can be in line contact with the inner surface of the valve seat 2a is attached to the valve seat member 2. Seat member 2
The flow rate of the pressurized fluid flowing between the valve seat and the valve body is controlled by shifting the throttle adjustment plate 4 which can be shifted in the axial direction of the valve.

Note that in order to shift the diaphragm adjustment plate 4 made of a magnetic material in the axial direction, the magnetic force of the electromagnet 5 that faces the diaphragm adjustment plate 4 and is arranged at a distance around the valve seat member 2 is changed, and the adjustment plate 4
All you have to do is change the suction force that acts on it. therefore,
By changing the current or voltage acting on the coil that constitutes the electromagnet, the force that shifts the valve body toward the valve seat (hereinafter referred to as the "throttling force") can be continuously adjusted, making it easy to operate and reducing the No mechanical problems such as rattling occur.

(Problems to be Solved by the Invention) However, in the electromagnetic flow control valve configured as described above, when the throttle adjustment plate 4 comes into contact with the spherical valve body 3, the throttle adjustment plate 4 is aligned with the axis of the valve seat member 2. There is a tendency for the contact to occur at a certain angle rather than at right angles to the direction, and since this slope changes each time the flow rate is adjusted and is not constant, the flow rate or pressure of the pressurized fluid discharged from the discharge port 1b fluctuates, making it difficult to accurately A drawback was that it was difficult to control the flow rate or pressure of the pressurized fluid.

Furthermore, the diaphragm adjustment plate 4 tends to generate self-excited vibrations, which causes oscillations when feedback control is performed on the flow rate control valve, so there is a problem in that the gain of the loop cannot be set large.

Such a problem can be solved by, for example, using two electromagnetic flow control valves (20a, 20b) as described above, electrically connecting these valves to each other via the voltage control means 21, and applying an effect to each valve 20a, 20b. This is particularly noticeable in the servo valve shown in FIG. 3(b), in which the voltages of the servo valves are changed in reverse order to adjust the throttling forces f, . . . f2, and the set pressure P is changed.

Therefore, in order to prevent self-excited vibration caused by so-called dancing between the diaphragm adjustment plate 4 and the spherical valve body 3, a gap is formed between the diaphragm adjustment plate 4 and the sealing member 6 to reduce the gap in the axial direction. Although it is conceivable to set the diaphragm adjustment plate so that it vibrates around the spherical valve body, the movable range of the valve body 3 becomes small and control of the valve body becomes difficult. This means that when two valves are combined and used as a servo valve, the response characteristics deteriorate.

(Means for Solving the Problem) In order to solve this problem, in the electromagnetic flow control valve of the present invention, in particular, a buffer member made of rubber or a rubber-like elastic sheet is arranged to face the diaphragm adjustment plate and connected to the drive means. The buffer member is provided such that the end face of the buffer member facing the aperture adjustment plate projects in the axial direction from the end face of the driving means facing the aperture adjustment plate.

(Function) Therefore, in the electromagnetic flow control valve configured as described above, in order to control the flow rate or pressure of the pressurized fluid, an electric signal is applied to the electromagnet to shift the orifice adjustment plate in the axial direction. When adjusting the opening degree of the valve, the throttle adjustment plate comes into contact with the spherical valve body and presses the valve body toward the valve seat, and also comes into contact with a buffer member made of rubber or a rubber-like elastic sheet. At this time, the throttle adjustment plate presses the valve body in the axial direction against the elastic force of the buffer member to provide a desired valve opening degree. On the other hand, since the diaphragm adjustment plate is in contact with the buffer member, it does not vibrate around the valve body.

(Example) The electromagnetic flow control valve of the present invention will be described below with reference to the drawings. Items with the same reference numerals as those in Figure Middle East 3 indicate equivalent items.

FIG. 1(a) shows a preferred embodiment of the present invention. Reference numeral 1 denotes a housing, which has a pressurized fluid inlet 1as and a discharge port. A valve seat member 2 is fixed to the introduction port 1a of the housing 1. Note that the O-ring 8a is inserted into the valve seat member 2,
The introduction port 1a and the valve seat member 2 are sealed. This valve seat member 2 has a base portion 9a at one end so that pressurized fluid can be supplied reliably and easily, and a valve seat 2a on which a spherical valve body 3 abuts at the other end.
hollow members each having a passageway through which a pressurized fluid flows. Note that in this embodiment, the base portion 9a
Although the valve seat 2a is integrally formed with the valve seat member 2, it may be formed separately.

- the valve seat 2a has a substantially conical inner surface so as to be in line contact with the valve body 3; Furthermore, considering that steel balls are usually used as the valve body, it is advantageous to form the valve seat 2a with alumina or silicon carbide ceramics in order to improve the wear resistance of the contact portion. . On the other hand, if a valve body made of plastic, preferably acetal resin, is used instead of steel balls, the valve body can be made lighter. Furthermore, it is possible to almost eliminate the noise generated when the valve body collides with the valve seat or throttle adjustment plate, and it also has the effect of increasing the life of the contact part, and is also highly resistant to chemicals.

Therefore, the control valve, including the valve body 3, is preferably selected appropriately depending on the pressurized fluid to be used.

A driving means consisting of an electromagnet 5 and a casing 10 is fixed to the housing 1 at a distance from the valve seat member 2 and concentrically with the axis of the valve seat member. Therefore, the pressurized fluid supplied from the mouthpiece 9a passes through the hollow valve seat member, passes through the opening formed between the valve seat 2a and the valve body 3, and connects the valve seat member and the driving means. It passes through the gap between them and is discharged from the discharge port 1b. A casing 10 that is fixed to the housing 1 and supports an electromagnet is
An opening is provided at the end face facing the diaphragm adjustment plate 4, and a buffer member 12 made of rubber or rubber-like elastic material is accommodated in the opening. One end surface of the buffer member 12 is set to the valve opening degree O when the throttle adjustment plate 4 brings the valve body 3 into complete contact with the valve seat 2a.
% to 100% valve opening, the throttle adjustment plate 4
protrudes in the axial direction so as not to come into direct contact with the end face of the drive means, in this embodiment the end face of the casing 10. Right buffer member 12. In particular, it is advantageous to use rubber or a rubber-like elastic material that has compliance comparable to that of general-purpose rubber in terms of durability and the movement of the aperture adjustment plate 4 in the axial direction. Its thickness is
When the valve opening is 0%, the gap d in the axial direction between the recess 11 that accommodates the diaphragm adjustment plate formed in the sealing member 6 so as to be able to shift in the axial direction, and the diaphragm adjustment plate 4 made of a magnetic material. (1st
In other words, it is preferably substantially the same as the movement distance of the aperture adjustment plate 4 in the axial direction.

Therefore, even if an electric signal is applied to the electromagnet 5 constituting the driving means to shift the diaphragm adjustment plate 4 toward the valve seat and press the valve body 3 toward the valve seat, it will not come into contact with the spherical valve body 3. Since the diaphragm adjustment plate 4 also contacts the buffer member 12 at its peripheral edge, it does not shift in any direction other than the axial direction, and the valve body 3
There is no vibration around the

The 0-IJ song b is inserted into the open end of the housing 1, and the sealing member 6 is sealed and fixed to the nozzle housing using the fastening bolt 7. In this embodiment, the sealing member 6 is provided with the recess 11 in order to allow the diaphragm adjustment plate 4 to move in the axial direction. In that case, the drive means is provided so as to be shifted toward the introduction port la in accordance with the moving distance of the diaphragm adjustment plate.

In addition, in order to absorb the inertial force acting on the aperture adjustment plate 4,
By arranging a low-elasticity sheet, such as a urethane foam sheet, in the recess 11 or on one side of the diaphragm adjustment plate facing the recess 11, the above-mentioned inertial force can be absorbed and vibration of the diaphragm adjustment plate can be more reliably prevented. can do.

The manner in which the flow rate (or pressure) of pressurized fluid is controlled using the electromagnetic flow control valve having such a configuration will be described below. It is assumed that a connection pipe connected to a supply source of pressurized fluid, such as an air compressor (not shown), is connected to the mouthpiece 9 of the control valve in a sealed manner. The pressurized air from the air compressor passes through the hollow part of the valve seat member,
Press the valve body 3 to the right as shown in Figure 1 (a), and open the discharge port 1.
b flows into another connecting pipe (not shown) connected to the base 1b via the mouthpiece 1b. To limit the flow rate of pressurized air flowing into other connecting pipes, an electric signal is applied to the electromagnet 5 constituting the drive means to move the throttle adjustment plate 4 toward the valve seat, that is, to the left in FIG. 1(a). move it towards the The diaphragm adjustment plate 4 presses the valve body 3 to the left against the force of pressurized air acting on the valve body 3, and the force acting on the diaphragm adjustment plate by the electromagnet 5.
It stops at a position where the force acting on the valve body 3 is balanced. Therefore, since the valve opening is reduced and the flow rate of pressurized air flowing through the control valve is reduced, a desired flow rate (or pressure) can be provided. At this time, the diaphragm adjustment plate 4 comes into contact with the valve body 3, and
Since the buffer member 12 is also in contact with its peripheral edge, the diaphragm adjustment plate 4 does not vibrate around the valve body 3 or shift in a direction other than the axial direction. In this embodiment, the buffer member 12 is fixed to the electromagnet 5 by known fixing means such as adhesive, but it can also be fixed to the inner end surface of the opening of the casing 10.

FIG. 2(a) shows another embodiment of the present invention. This embodiment has almost the same structure as the embodiment shown in FIG. 1(a), but the housing 1 is provided with an inlet 1a for pressurized fluid,
The discharge port 1b is provided in the sealing member 6.

The pressurized fluid led into the housing 1 from the valve seat member 2 passes through at least one, four in this embodiment, through holes 14 that pass through the throttle adjustment plate 4 in the axial direction, and then passes through the outlet. 1b (see FIG. 2(b)).

Even in conventional electromagnetic flow control valves, it is possible to provide a through hole that passes through the throttle adjustment plate in the axial direction and discharge the pressurized fluid from the discharge port provided in the sealing member. Since the throttle adjustment plate vibrates violently around the valve body due to the energy of the pressurized fluid passing through the adjustment plate, it cannot function as a flow rate control valve.

In contrast, in the electromagnetic flow control valve of the present invention, the vibration of the throttle adjustment plate 4 and deviation in directions other than the axial direction are prevented by the buffer member 12. There will be no deviation.

Also in the embodiment shown in FIG. 2(a), in order to absorb the inertial force acting on the diaphragm adjustment plate 4, a low elasticity sheet such as a urethane foam sheet is placed in the gap between the diaphragm adjustment plate 4 and the recess 11. Of course, it is also possible to arrange the .

Furthermore, an inlet port of another electromagnetic flow control valve having substantially the same configuration is connected to the outlet port 1b of the valve shown in FIG. 2(a), and a port (not shown) is connected from the outlet port 1b. A connecting pipe that supplies pressurized air to an actuator such as an air cylinder is connected to this port, and the pressure applied to the actuator is controlled by controlling the electric signal that acts on the electromagnet. You can also freely control the air pressure.

(Effects of the Invention) As detailed above, in the electromagnetic flow control valve of the present invention, a buffer member made of rubber or a rubber-like elastic sheet is provided in the driving means to face the diaphragm adjustment plate, and the end surface of the buffer member protrudes from the end surface of the drive means in the axial direction toward the throttle adjustment plate, so that the throttle adjustment plate is in contact with the valve body and always in contact with the buffer member, thereby being displaced in the axial direction. Therefore, the throttle adjustment plate faithfully shifts in the axial direction and presses the valve body toward the valve seat, and does not shift in any direction other than the axial direction, and does not vibrate around the valve body. To obtain an electromagnetic flow control valve which is free from various problems caused by vibration of a throttle adjustment plate and has excellent static and dynamic characteristics.

Furthermore, even if a through-hole is provided that passes through the throttle adjustment plate and pressurized fluid flows through the through-hole, the throttle adjustment plate will not vibrate due to the energy of the pressurized fluid, so the valve will not vibrate like in conventional devices. There is no need to provide a discharge port that intersects the axis of the seat member, and the degree of freedom in design is increased, such as the ability to reduce the dimensions of the valve, especially the outer diameter. Furthermore, the valves can be integrally connected and used as if they were a single servo valve.

[Brief explanation of the drawing]

FIG. 1(a) is a cross-sectional front view showing the electromagnetic flow control valve of the present invention, FIG. 1(b) is an explanatory diagram showing a part of FIG. 1(a), and FIG. (a) is a cross-sectional front view showing another embodiment of the present invention; FIG. 2(b) is a plan view of an aperture adjustment plate used in the embodiment of FIG. 2(a); ) and (b) are a sectional view showing a known electromagnetic flow control valve and a diagram showing the operating principle of a servo valve using the electromagnetic flow control valve. 1...Housing 1a...Inlet port 1b...
・Discharge port 2... Valve seat member 3... Valve body
4... Aperture adjustment plate 5... Electromagnet
6... Sealing member 7... Fastening bolt 3
a, gb...0-ring 9a, 9b...cap
10...Casing 11...Concave part
12...Buffer member 14...Through hole Fig. 3 (a) (b)

Claims (2)

[Claims] 1. a housing having an inlet and an outlet for pressurized fluid; a valve seat member having a valve seat connected to the inlet and extending inward of the housing and having a substantially conical inner surface; and a valve seat member capable of being in line contact with the valve seat. A spherical valve body, an aperture adjustment plate made of a magnetic material that is arranged to face the valve seat via the valve body and can be shifted in the axial direction of the valve seat member, and an aperture adjustment plate that is fixed to the housing. In an electromagnetic flow control valve that includes a driving means having an electromagnet that deflects the valve toward the valve seat and a sealing member that seals the open end of the housing, the buffer member made of rubber or a rubber-like elastic sheet is throttled. An electromagnetic flow rate system characterized in that the buffer member is provided on the drive means to face the plate, and the end face of the buffer member facing the aperture adjustment plate is made to protrude at least in the axial direction from the end face of the drive means facing the aperture adjustment plate. control valve. 2. 2. The electromagnetic flow control valve according to claim 1, wherein the discharge port is provided in the sealing member, and a through hole for guiding the pressurized fluid to the discharge port is provided in the throttle adjustment plate.