JPH0447435Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field to which the invention pertains] The present invention is a single-layer vibrator made of a ceramic or organic piezoelectric material with electrodes formed on both sides, or a single-layer vibrator made of two piezoelectric materials. It relates to a pump that uses a laminated vibrator (referred to as a bimorph vibrator) in which electrodes are provided on the laminated surface and both surfaces of the laminated casing. The flat casing is provided with a suction passage and a discharge passage supported by a rubber sealing material, and which suctions and discharges fluid by applying an alternating voltage between the electrodes of the piezoelectric vibrator and vibrating the piezoelectric vibrator. The present invention also relates to a piezoelectric vibrator pump having check valves for suction and discharge in the discharge passages, respectively.

[Prior art]

FIGS. 1a and 1b are a plan view and a partially sectional side view of an example of a conventional piezoelectric vibrator pump, respectively.

In FIG. 1, numeral 1 denotes a flat casing consisting of an upper casing 1a, a frame-shaped middle casing 1b, and a lower casing 1c. Reference numeral 2 denotes a bimorph vibrator in which two piezoelectric bodies are bonded together and electrodes are provided on the bonded surface and both surfaces. The outer peripheral portion of this bimorph resonator 2 is supported by a silicone rubber sealing material 3 on the inner peripheral surface of a frame-shaped middle casing 1b. Numerals 4 and 5 are a suction passage and a discharge passage provided in the upper casing 1a, respectively, and 6 and 7 are check valves for suction and discharge provided in the suction passage 4 and discharge passage 5, respectively.

The discharge check valve 7 communicates with the inlet 8 within a valve case 10 having an inlet 8 communicating with the discharge passage 5 and an outlet 9 (which serves as the discharge outlet of the pump) connected to an external flow path. Valve seat 1 with passage 11
2 is provided in the passage 11 of the valve seat 12, and a ball 13 for opening and closing the passage 11 is pressed by a spring 14 so as to close the passage 11.

The suction check valve 6 also has a similar configuration, and 15 is an inlet port (which serves as the suction port of the pump) connected to the external flow path. 24a, 24b
is a lead wire for applying an alternating voltage between the bonded surface electrode and the double-sided electrode of the bimorph resonator.

Such a conventional piezoelectric vibrator pump has lead wires 24a and 24b between the electrodes of the bimorph vibrator 2.
When an alternating current voltage is applied through the bimorph oscillator 2, the bimorph oscillator 2 vibrates in the vertical direction as shown in FIG. 1b at a frequency determined by the frequency. When the bimorph oscillator 2 is displaced downward and the space A above it becomes negative pressure, the spring 14 of the discharge check valve 7 and the pressure on the discharge port 9 side increase, causing the discharge check valve 7 to close. At the same time as the suction port 15 is closed, the pressure on the suction port 15 side increases, so the suction check valve 6 is opened against the spring, and the fluid is transferred from the suction port 15 to the bimorph oscillator 2.
When the bimorph vibrator 2 is displaced upward and the space A above it becomes positive pressure, the suction check valve 6 closes and the discharge check valve closes, contrary to the above. 7 is opened, and the fluid in the upper space A is discharged from the discharge port 9. Such operations are repeated to continuously suck in and discharge fluid.

However, in this conventional piezoelectric vibrator pump, a ball 13 and a spring 14 are used as a check valve.
Since the check valves 6 and 7 using or
Since the ball 13 does not vibrate following the 60 times/sec, the opening/closing operation cannot be performed reliably, and the closing operation is incomplete, which not only causes fluid leakage and poor pump efficiency, but also requires the use of the ball 13 and spring 14. Therefore, the check valves 6 and 7 have a short lifespan, are complex, difficult to make thin, and expensive, and are an impediment to making the pump thinner and cheaper.

[Purpose of invention]

The present invention was made in view of the above points, and its purpose is to improve pump efficiency by making the check valve an umbrella-shaped valve structure.
Another object of the present invention is to provide a piezoelectric vibrator pump in which the check valve is made thinner and less expensive, thereby achieving a thinner and less expensive pump.

[Structure of the idea]

The piezoelectric vibrator pump of the present invention, which has achieved the above object, has a flat casing 1 as shown in Fig. 2a and b.
A piezoelectric vibrator 2 having a plate-shaped piezoelectric material on the inner peripheral surface of the piezoelectric vibrator 2
A suction passage 4 and a discharge passage 5, which support the outer circumference of the piezoelectric vibrator 2 and apply an alternating voltage between the electrodes of the piezoelectric vibrator 2 to vibrate the piezoelectric vibrator 2 to suck in and discharge fluid, are connected to the flat casing 1. In preparation for this, in this piezoelectric vibrator pump in which the suction passage 4 and the discharge passage 5 are provided with check valves for suction and discharge, respectively, the suction passage 4 and the discharge passage 5 are bored in the wall of the flat casing 1 facing the piezoelectric vibrator. The piezoelectric vibrator has an insulating paint applied on the electrodes formed on both sides of the piezoelectric body, and a film made of a corrosion-resistant material is adhered to the outer surface of the piezoelectric vibrator, and is used as the suction and discharge check valve.
Umbrella-shaped valves 19 and 20 are used, which have a structure in which an umbrella-shaped elastic valve body 18 that opens and closes the communication holes 16 and 16 is attached to a partition wall 17 having communication holes 16 and 16 so as to cover the communication holes 16 and 16. Configure.

[Configuration of Example]

As the piezoelectric material constituting the piezoelectric vibrator 2 of the present invention, a ceramic piezoelectric material or an organic piezoelectric material can be used. As ceramic piezoelectric materials, barium titanate, lead titanate, lead titanate, lead zirconate, titanium/zirconate, magnesium niobate, lead titanium zirconate, etc. can be used, and organic piezoelectric materials can be used. As the body, a material formed by kneading ceramic ferroelectric powder into a uniaxially stretched product of PVDF, a synthetic resin such as polyacetal or polyamide, etc. can be used.

The piezoelectric vibrator 2 may be a single-layer type in which film-like electrodes are formed by metal vapor deposition or adhesion of metal foil on both sides of a thin piezoelectric material having a thickness of 0.5 to 3 mm. , it is preferable to make a bimorph vibrator made by laminating two thin plate-like piezoelectric materials and forming a membrane electrode on the laminated surface and both surfaces. In particular, a phosphor bronze thin plate is inserted into the membrane electrode on the laminated surface. A bonded structure is preferable in order to obtain large vibrations.

Further, the surface of the piezoelectric vibrator 2 is coated with an insulating paint such as epoxy paint to form an insulating layer for both protection and insulation, and the outer surface is coated with silicone rubber, polyethylene, nylon, polyester, etc.
Glue a film made of corrosion-resistant material such as fluorine-based resin.

Since the frequency of the AC voltage applied to the piezoelectric vibrator 2 is not particularly limited, it is convenient to use the frequency of the commercial power source.

The suction passage 4 and the discharge passage 5 are bored in a wall of the flat casing 1 facing the piezoelectric vibrator 2, and are provided in a direction perpendicular to the surface of the piezoelectric vibrator 2.

The elastic valves 18 of the umbrella-shaped pieces 19 and 20 may be made of silicone rubber, natural rubber, synthetic rubber (SBR, chloroprene, neoprene, NBR, etc.), synthetic resin (ethylene/vinyl acetate copolymer, thermoplastic elastomer, etc.), etc. can be used.

The check valve for suction and discharge of a piezoelectric vibrator pump is provided with a partition wall 17 having a plurality of communication holes 16, 16 on the inner periphery of the central part of the valve case 21, as shown in FIGS. 3a and 3b. Umbrella-shaped valves 19 and 20 having a structure in which an umbrella-shaped elastic valve body 18 that opens and closes the communication holes 16 and 16 are attached to the partition wall 17 so as to cover the communication holes 16 and 16 are used. The elastic valve body 18 is attached to the partition wall 17 by, for example, fitting and engaging the central head portion 18a of the elastic valve body 18 into a hole provided at the center of the partition wall 17.

As shown in FIG. 2b, this suction umbrella-shaped valve 19 is housed by fitting, screwing, etc. into an accommodation hole formed in the upper casing 1a so as to communicate with the suction passage 4, with the discharge side facing the suction passage 4. The discharge umbrella-shaped valve 20 is also housed in an accommodation hole formed in communication with the discharge passage 5 of the upper casing 1a, with the suction side facing the discharge passage 5.

[Effect of the embodiment]

Next, its effect will be explained. Bimorph oscillator 2
When commercial power is applied between the electrodes of the bimorph oscillator 2 through the lead wires 24a and 24b, the bimorph resonator 2 vibrates at a frequency of 50 or 60 determined by the frequency of 50Hz or 60Hz.
It vibrates in the vertical direction as shown in FIG. 2b at a rate of rotation/sec. When the bimorph oscillator 2 is displaced downward and the space A above it becomes negative pressure, the pressure on the discharge port 9 side becomes higher than the pressure on the suction side, and the discharge umbrella valve 2
The valve body 18 of the suction umbrella valve 19 is deformed by the pressure difference as the pressure on the suction port 15 side becomes higher than the pressure on the discharge side. The communication hole 16 is opened, and fluid is sucked into the space A above the bimorph vibrator 2 from the suction port 15 through the communication hole 16 and the suction passage 4. Further, when the bimorph oscillator 2 is displaced upward and the space A above it becomes positive pressure, contrary to the above, the suction umbrella valve 19 closes and the discharge umbrella valve 2
0 is opened and the fluid in the upper space A is discharged from the discharge port 9.
Discharge more. Such operations are repeated to continuously suck in and discharge fluid.

[Effects of Examples]

In this embodiment, as described above, the umbrella-shaped valve 1 uses an umbrella-shaped elastic valve body 18 as a check valve for suction and discharge.
Since 9 and 20 are used, the bimorph oscillator 2
Since the elastic valve body 18 displaces and vibrates in accordance with the frequency of the vibration, it opens and closes reliably, so there is no risk of fluid leakage, which not only improves pump efficiency, but also eliminates the need for metal parts since no springs are used. It has a long life, and can be simpler, thinner, and less expensive than the check valves 6 and 7 that use balls and springs. Therefore, since the umbrella valves 19 and 20 can be embedded in the flat casing 1, the pump can be made thinner and less expensive.

A piezoelectric vibrator pump using the conventional check valves 6 and 7 and a piezoelectric vibrator pump using the check valves 19 and 20 of the present invention are combined by connecting a 60Hz, 100V commercial power source between the electrodes of the bimorph vibrator 2 of the same size. When connected and operated by vibrating the piezoelectric vibrator 2, the discharge pressure of the piezoelectric vibrator pump of the present invention was approximately twice that of the conventional piezoelectric vibrator pump, and the discharge capacity of the piezoelectric vibrator pump of the present invention was found to be approximately twice that of the conventional piezoelectric vibrator pump. has been proven to be superior.

In the present invention, the inner surface of the umbrella portion of the valve body 18 of the umbrella-shaped valves 19 and 20 has a large number of radial grooves 22 as shown in FIG.
These grooves 22 can improve fluid flow and improve responsiveness.

In addition, in this invention, bimorph oscillator 2
The pump may be made into a multi-layered type to further improve the pumping capacity.

[Effect of idea]

As is clear from the above description, according to the piezoelectric vibrator pump of the present invention, the outer circumference of the piezoelectric vibrator 2 is supported on the inner circumferential surface of the flat casing 1, and an alternating current voltage is applied between the electrodes of the piezoelectric vibrator 2. The flat casing 1 is provided with a suction passage 4 and a discharge passage 5 for sucking and discharging fluid by vibrating the piezoelectric vibrator 2 by applying an electric current. In the piezoelectric vibrator pump provided with the above-mentioned suction and discharge check valves, a partition wall 17 having communication holes 16, 16 is provided with a communication hole 1.
Since the umbrella-shaped elastic valve body 18 that opens and closes the piezoelectric vibrator 2
The elastic valve body 18 displaces and oscillates in accordance with the frequency of the vibration, and opens and closes reliably, so there is no risk of fluid leakage, which not only improves pump efficiency, but also has a long life because no springs are used. , and can be simpler, thinner, and less expensive than the check valves 6 and 7 that use balls and springs, and the umbrella valves 19 and 20 can be embedded in the flat casing 1, making the pump easier to use. Thinness and cost reduction can be achieved. In addition, since the check valves for suction and discharge are provided on the wall of the flat casing 1 facing the piezoelectric vibrator, the diameters of the suction passage 4 and discharge passage 5 can be increased, and the flow resistance of the fluid can be reduced. Even if the diameters of the passage 4, the discharge passage 5, or the suction and discharge check valves are made large, the piezoelectric vibrator 2 and the wall of the flat casing 1 can be installed close to each other, thereby minimizing the volume of the pump chamber. I can do it. Therefore, even in a pump such as a piezoelectric vibrator pump in which the volume of the pump chamber changes little, it is possible to avoid the defect that the discharge amount decreases due to elastic compression of the gas to be fed. Furthermore, since a large number of grooves 22 are formed radially on the inner surface of the umbrella portion of the valve body 18 of the umbrella-shaped valves 19, 20, the grooves 22 improve the flow of fluid, and as a result, the responsiveness of the check valve is improved. be able to.

In addition, since an insulating paint is applied on the electrodes of the piezoelectric vibrator 2 and a film made of a corrosion-resistant material is adhered to the top surface of the insulating paint, stress caused by displacement of the piezoelectric vibrator 2 is dispersed, causing breakage of the piezoelectric body. Accidents such as electrode breakage can be prevented, and the durability of the piezoelectric body and electrodes can be improved, and the reliability of the pump as a whole can be improved.

[Brief explanation of the drawing]

Figures 1a and b are a plan view and a partially sectional side view of an example of a conventional piezoelectric vibrator pump, respectively, and Figures 2a and b are an embodiment of the piezoelectric vibrator pump of the present invention, respectively. 3A and 3B are sectional views of the suction umbrella-type valve and the discharge umbrella-type valve used in the present invention, respectively, and FIG. , is a back view showing the elastic valve body of the discharge umbrella-shaped valve. DESCRIPTION OF SYMBOLS 1... Flat casing, 2... (bimorph) piezoelectric vibrator, 3... Rubber sealing material, 4... Suction piezoelectric passage, 5... Discharge passage, 9... Discharge port, 1
5... Suction port, 16... Communication hole, 17... Partition wall, 18... Umbrella-shaped elastic valve body, 19, 20... Umbrella-shaped valve for suction and discharge, 21... Valve case, 22...
...Groove, 23...Irregularities, 24a, 24b...Lead wire.

Claims (1)

[Claims for Utility Model Registration] The outer periphery of a plate-shaped piezoelectric vibrator is supported on the inner peripheral surface of a flat casing, and an alternating current voltage is applied between the electrodes of the piezoelectric vibrator to vibrate the piezoelectric vibrator. In a piezoelectric vibrator pump, a piezoelectric vibrator pump is provided with a suction passage and a discharge passage for sucking and discharging fluid in a flat casing, and check valves for suction and discharge are provided in the suction passage and discharge passage, respectively. is bored in the wall facing the piezoelectric vibrator of the flat casing, and the piezoelectric vibrator is
An insulating paint is applied on the electrode formed on the surface of the piezoelectric body, and a film made of a corrosion-resistant material is adhered to the outer surface of the electrode, and the communication hole is attached to the partition wall having a communication hole to serve as the above-mentioned suction and discharge check valve. 1. A piezoelectric vibrator pump characterized in that the piezoelectric vibrator pump is constructed using an umbrella-shaped valve having a structure in which an umbrella-shaped elastic valve element having a radial groove on the inner surface of the umbrella part is attached to cover the communication hole.