JPS61236974A - Fluid control valve - Google Patents

Abstract

PURPOSE:To produce a fluid control valve which is less in consumed electric power and of simple construction by providing a holding means to stick the peripheral edge of a disc-shaped piezoelectric element fast to the side of valve housing. CONSTITUTION:Since a disc-shaped piezoelectric element 13 is flat under the condition of no applied voltage, a elastic valve seat 23, 24 come into contact with the lower surface of the piezoelectric element to close the flow path of fluid. The applied voltage bends the central part of the disc-shaped piezoelectric element 13 into a convex shape, and an inlet port 20 therefore communicates with an outlet port 21 to form a fluid flow path. The said bending quantity can be controlled by the value of the applied voltage, and the area of the fluid flow path can be therefore controlled by the applied voltage. Since the upper surface of the peripheral edge 16 of the disc-shaped piezoelectric element 13 comes into contact with a solid holding case 19, but its lower surface comes into contact with a elastic ring 18, in bending of the piezoelectric element 13, the deformation of the elastic ring 18 does not check its bending.

Description

[Detailed description of the invention] Industrial application field Kibatsu F! A relates to a fluid control valve for flow rate adjustment, which is applied to combustion equipment using fluid fuel such as scum or petroleum, or to a control mechanism using air mold pressure.

BACKGROUND OF THE INVENTION A control valve that continuously changes the fluid flow rate using an electric signal is used, for example, in an instantaneous water heater that stabilizes the hot water temperature by controlling the amount of heat generated by combustion.

An example is shown in Figure @3. (Japanese Utility Model Publication No. 59-18216) In this system, a valve body 4 is provided at the lower end of a plunger 3 whose central portion is supported by a leaf spring 2, and a gas passage 'b
It is for adjusting the opening degree of the valve hole 6 formed with Vc. As the coil current increases, the plunger 3 is attracted upward and the valve opening increases, making it possible to control the gas amount by the current value. This configuration satisfies the condition that the attraction force of the plunger 3 and the reaction force of the leaf spring 2 are balanced since the position of the granger 3 is continuously varied, resulting in a magnetic circuit with many magnetic gaps. Therefore, a problem arises in that a large amount of current is required to be supplied to the coil, and the capacity of the drive power source is inevitably increased. next,
FIG. 4 shows an example in which a piezoelectric element is used as a drive source.

(Japanese Unexamined Patent Publication No. 60-4682) This increases the amount of displacement by connecting the two piezoelectric elements 7 and 8 at both ends with spacers 9, and the valve body 10 interlocks with the center of the lower piezoelectric element 8. The opening degree of the valve hole 12 provided in the passage 11 is adjusted. Since the amount of deformation changes depending on the applied voltage, the valve opening can be adjusted by voltage control, and power consumption is minimal.

In this configuration, the valve part and the driving part are formed separately, and in order to eliminate external leakage of fluid, it is necessary to provide an airtight seal at the part of the valve body 10 or to make the storage part of the driving part a sealed structure. The former causes hysteresis due to lack of smoothness of operation, and the latter causes structural complexity.

Problems to be Solved by the Invention As mentioned above, the conventional examples have the problem of high power consumption or structural complexity.The present invention provides a fluid with low power consumption and a simple structure. The purpose is to obtain a control valve.

Means for Solving the Problems In order to solve the above problems, the fluid control valve of the present invention includes a disc-shaped piezoelectric element, an inlet hole formed corresponding to the central flat surface of the disc-shaped piezoelectric element, and A valve ring having an outlet hole, a sealing means for airtightly sealing between the valve ring and the peripheral edge of the disc-shaped piezoelectric element, and a holding means for tightly contacting the peripheral edge of the disc-shaped piezoelectric element to the valve housing side. It is.

With the above configuration, the deflection of the central part of the disc-shaped piezoelectric element due to voltage application changes the passage area of the inlet hole and the outlet hole, making it possible to adjust the flow rate by voltage control. . Further, since the piezoelectric element is disk-shaped and its peripheral edge is held and is configured to be airtight 11, there is no fear of external leakage. In this way, the disk-shaped piezoelectric element itself is a valve body that regulates the flow rate, and is a part of the sealing means to prevent external leakage, so that it is possible to reduce power consumption and simplify the configuration. Embodiment t of the present invention will be described below based on the attached drawings. In FIGS. 1(A) and 1(B), the disk-shaped piezoelectric element is made by pasting a 13-layer piezoelectric ceramic material 14 on a metal disk 15, and the lower surface of the peripheral edge 16 is provided in the groove of the valve ring 17. It is in contact with the elastic ring 18, and its upper surface is pressed by a holding case 19 and is in close contact with the elastic ring 18.

An inlet hole 2o and an outlet hole 21 are provided in the valve hook ring 17 in correspondence with the flat lower surface of the disc-shaped piezoelectric element 13, and are arranged in series as a flow path 22. Then, an elastic valve seat 2a made of rubber or the like is provided at a portion in contact with the disc-shaped piezoelectric element 13.
and 24 are fixed to the inlet hole 2o and the outlet hole 21, respectively. Flexible wires 25 and 26 are connected to the disc-shaped piezoelectric element 13, and voltage is applied from terminals 27 and 28.

In the above configuration, when the applied voltage is zero, the disk-shaped piezoelectric element 13I/'i is flat, so the elastic valve seats 23 and 24
is in contact with the lower surface of the piezoelectric element, and the flow path is closed. When a voltage is applied, the disc-shaped piezoelectric element 13 as shown in FIG. 1(B)
The central part of the inlet hole 20 and outlet hole 21t' are bent in a convex shape.
i communicate with each other to form a fluid passage. Since the amount of deflection at this time can be controlled by the voltage value, the fluid passage area can be adjusted by the voltage. Peripheral portion 16If of disk-shaped piezoelectric element 1a
i The upper surface is in contact with the holding case 19, which is a rigid body, but the lower surface is in contact with the elastic ring 18, so when the elastic ring 18 is bent, the elastic ring 18 does not deform and hinder the bending. An example of this will be explained based on Figure @2. An elastic sheet 29 is pasted on the lower surface of the disc-shaped piezoelectric element 1a, and a seal ring 30 protruding inward is integrally molded at the bent lower part of the elastic sheet 29. The seal ring 30 is in close contact with the valve seal ring 17 in the radial direction to form an airtight state. The circumferential edge of the upper surface of the disc-shaped piezoelectric element 13 is pressed and held toward the valve housing 1 by a spring 32 via a retaining ring a1.

With this configuration, when no voltage is applied as shown in FIG. 2(A), the flat surface of the disc-shaped piezoelectric element 13 is
9 is pressed against the inlet hole 20 and the outlet hole 21, and the flow path is closed. Next, when a voltage is applied, the flow path becomes open as shown in FIG. 1B, and the passage area can be controlled by the voltage value, similar to the embodiment shown in FIG. 1. In this configuration, since the disc-shaped piezoelectric element 13 is pressed and held by the spring 32, the deflection is not hindered, and a larger opening area than the embodiment shown in FIG. 1 can be obtained. Furthermore, since it is completely separated from the fluid passage 22 by the elastic sheet 29, it is suitable for fluids that require electrical insulation.

Effects of the Invention As described above, the fluid control valve of the present invention provides the following effects.

(1) Since the disk-shaped piezoelectric element is used as the driving source, power consumption is low, and the structure can be simplified because the disk-shaped peripheral portion has a sealed structure and the central portion is used as a valve body.

(2) Since there is no resistance element such as a sliding part to the operation of the disc-shaped piezoelectric element, there is no operation hysteresis.

(3) The structure is such that the disc-shaped piezoelectric element contacts the fluid only on at least one side, so that no potential difference is applied to the fluid. Therefore, it is safe when used for fluids with low electrical resistance or flammable fluids, and does not cause an increase in power consumption due to leakage current.

[Brief explanation of drawings]

41111 is a vertical cross-sectional view of a fluid control valve according to the first embodiment of the present invention, FIG. 2 is a vertical cross-sectional view of the second embodiment, FIG. 3 is a vertical cross-sectional view of a conventional fluid control valve, and FIG. The figure is a longitudinal sectional view of another conventional example. 1G...disc-shaped piezoelectric element, 16...disc-shaped piezoelectric element periphery, 17...valve nozzle, 18...elastic ring, 19-... Holding case, 20... Inlet hole, 21... Outlet hole, 29... Elastic sheet, 30...
Seal ring, 32...Name of spring agent
Patent attorney Toshio Nakao and 1 other person 29-11 Book A sheet (A) (β) 2nd
Figure CA) CB) Figure 3 Figure 4

Claims (2)

[Claims] (1) A disk-shaped piezoelectric element whose central portion is deformed by voltage application; a valve housing having an inlet hole and an outlet hole formed corresponding to the central flat surface of the disk-shaped piezoelectric element; A fluid control valve comprising a sealing means for airtightly sealing a peripheral edge of a disk-shaped piezoelectric element, and a holding means for tightly contacting a peripheral edge of the disk-shaped piezoelectric element to a valve housing side. (2) The fluid control valve according to claim 1, wherein the sealing means is constituted by an elastic member whose central portion is deformed integrally with the piezoelectric element and whose peripheral portion is in close contact with the valve housing in the radial direction.