JPH0574720B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a support structure for a piezoelectric fan in a piezoelectric fan device incorporating a piezoelectric fan using a piezoelectric bimorph element.

Conventional Technology A piezoelectric fan device that incorporates a piezoelectric fan using a piezoelectric bimorph element into an air intake device for an indoor temperature sensor in an air conditioner, a computer cooling device, a convection device in an oven, a defrost device in a refrigerator, etc. is known to be used.

As an application example of this piezoelectric fan device, an example in which it is used as an inside temperature sensor of an auto air conditioner will be explained with reference to FIG. and a lower space for accommodating an internal temperature calculation circuit, and an upper cover 2 is screwed to the upper space, and a lower cover 3 is screwed to the lower space. An air intake port 4 and left and right air discharge ports 5, 6 are provided in the upper space, and a piezoelectric fan 7 using a piezoelectric bimorph element is mounted on a support 8 between the air intake port 4 and the air discharge ports 5, 6. is supported and fixed to the casing 1. The support body 8 is a U-shaped support, into which the piezoelectric fan 7 is fitted, a presser plate 9 is applied, and the support plate 8 is fixed with screws 10. The structure of the piezoelectric fan 7 will be explained according to FIG. 7. Reference numerals 71 and 72 are piezoelectric bimorph elements made of semiconductor porcelain made of lead zirconate titanate, and electrodes 73 and 7 are provided on both sides of each piezoelectric fan 7.
4, 75, and 76 are formed into thin films by a printing method, plating method, vapor deposition method, or the like. Its material is
These include Ag, Ni, Al, etc. A reinforcing plate/diaphragm 70 made of a metal such as Kovar whose coefficient of thermal expansion is close to that of the piezoelectric bimorph elements 71 and 72 is sandwiched between the piezoelectric bimorph elements 71 and 72. , 75 by adhesive or soldering. The right side of the diaphragm 70 in the figure protrudes dimensionally long from the piezoelectric bimorph elements 71 and 72, and vibrates at this protrusion, and a lead wire 77 is connected to the left side. . In addition, piezoelectric bimorph elements 71, 7
The second electrodes 73 and 76 are sandwiched between electrode plates 78 made of a metal with good electrical conductivity such as copper. One of the piezoelectric bimorph elements 71 is polarized in the direction of the arrow X in the figure, and the other piezoelectric bimorph element 72 is also polarized in the X direction. By applying an alternating voltage between the diaphragm 70 and the electrode plate 78, the tip of the diaphragm 70 vibrates in the direction of arrow A in the figure.

Problems to be Solved by the Invention In the conventional piezoelectric fan support structure as described above, screws must be prepared separately from the support, the structure is complicated, and a screw tightening process is required. Furthermore, the support method of screwing has a problem of poor vibration resistance.

In addition, if a method such as caulking with a metal plate or the like is adopted instead of using screw tightening means, excessive pressure is generated in some parts, and the piezoelectric bimorph element, whose material is brittle, cannot withstand this excessive pressure and cracks from there. will occur.

The present invention aims to solve the above-mentioned problems by devising a means for easily fixing a piezoelectric fan to a support body without using conventional fixing means such as screwing or caulking.

Means for Solving the Problems As a means for solving the above problems, the present invention provides a piezoelectric fan device in which a piezoelectric fan using a piezoelectric bimorph element is supported by a support and housed in a casing. The support body is formed into a hollow cylindrical body, two axially opposing grooves are provided in the circumferential wall of the cylindrical body, the piezoelectric fan is fitted and supported in the grooves, and an adhesive is poured into the pair of hollow cylinders. The piezoelectric fan is solidified to form a piezoelectric fan support structure in which the piezoelectric fan and the support are integrated.

Embodiments Examples of the present invention will be described with reference to the drawings.

1, 2, and 3 show a first embodiment of the present invention, in which the same parts as the conventional device shown in FIG.
Or corresponding parts are indicated by the same reference numerals as in FIG. Therefore, a description of the parts common to these conventional devices will be omitted.

The present invention is characterized by the structure of the support body 8 for supporting the piezoelectric fan 7.

In this embodiment, the support 8 is formed into a rectangular cylinder as shown in FIG. 2, and its base 80 is slightly enlarged for reinforcement, and is formed integrally with the casing 1. A piezoelectric fan 7 is mounted on the peripheral wall of this square cylinder.
Two axially opposed grooves 81, 81 are provided having a width slightly greater than the thickness. This groove 8
The distance from the bottom end of the piezoelectric fan 7 to the bottom surface of the casing 1 is 1.5 mm, and this distance directly serves as the clearance between the piezoelectric fan 7 and the casing 1.

On the other hand, a wiring lead wire tip clip 11 and a wiring lead wire tip soldering portion 12 are attached to the piezoelectric fan 7. The dimensions of this piezoelectric fan 7 are width
22mm, length 60mm, thickness 0.7mm, and the applied voltage is
50V _pp , resonance frequency 70Hz, and air volume as an air introduction fan for the inside temperature sensor is 1 m ² /h. This piezoelectric fan 7 is connected to the opposing grooves 81, 81 of the square tube support 8.
After fitting and fixing from above, an epoxy resin adhesive is injected into the hollow part of the square tube support 8 and solidified to securely fix the piezoelectric fan 7. 13 is a thermistor for an internal temperature sensor. FIG. 3 is a top view showing the state in which the piezoelectric fan 7 is assembled into the opposing grooves 81, 81, and shows the state in which the epoxy resin adhesive 90 has been injected and solidified into the hollow portion of the square tube 8.

In FIG. 1, when an AC voltage is applied to the piezoelectric fan 7 through the lead wires connected to the tip clip 11 and the tip soldered portion 12, the diaphragm 70 of the piezoelectric fan bends and vibrates as shown by the dashed line.
Therefore, similar to the blowing effect of a fan or the like, air is sucked in from the intake port 4 in the direction of the arrow, passes through the passage in the casing 1, and is discharged from the left and right outlets 5 and 6. Thermistor 13 installed in the passage during this time
The temperature of this air can be measured by

With the support structure of the piezoelectric fan as described above, the piezoelectric fan 7 is fitted into the two opposed grooves 81, 81, so it can be easily positioned both vertically and horizontally, and the assembly operation is simple. By pouring the adhesive 90 into the portion and solidifying it, the piezoelectric fan can be supported and fixed more reliably.

A second embodiment of the invention is shown in FIG. In this embodiment, the support body 8 is cylindrical. As in the first embodiment, two axially opposing grooves 81, 81 are provided on the peripheral wall.
1 into which a piezoelectric fan 7 is fitted and supported.

A third embodiment of the invention is shown in FIG.

In this embodiment, the support body 8 has an elliptical cylindrical outer shape so as to have a streamlined shape with low air resistance. The two opposing grooves 81, 81 are made long so as to provide as stable support as possible.

As can be seen in each of the above embodiments, the shape of the support 8 is not fixed, and the shape of the hollow part does not have to match the outer shape of the support 8. Any hollow cylindrical body is sufficient.

Effects of the Invention As described above, the present invention can support and fix the piezoelectric fan by simply forming the support body of the piezoelectric fan into a hollow cylindrical shape and fitting and fixing the piezoelectric fan into the groove provided in the peripheral wall thereof. It is easy to operate, does not require screws, etc. for fixing, and has a small number of parts, resulting in an inexpensive support structure. Furthermore, since no fixing means such as screwing or caulking is used, it is particularly suitable for supporting fragile piezoelectric elements.

Furthermore, since the piezoelectric fan and the support are integrated by pouring the adhesive into the hollow cylinder and solidifying it, the support structure of the piezoelectric fan can be made more solid.

[Brief explanation of the drawing]

Fig. 1 is an overall perspective view of a first embodiment of the present invention, Fig. 2 is an enlarged perspective view of the main parts of the same embodiment, and Fig. 3 shows a piezoelectric fan in the above embodiment fixed to a support body. A top view, FIG. 4 is an enlarged perspective view of the main part of the second embodiment of the present invention, FIG. 5 is an enlarged perspective view of the main part of the third embodiment of the invention, and FIG. 6 is a conventional piezoelectric fan device. FIG. 7 is a plan view of the piezoelectric fan. 1...Casing, 4...Air suction port, 5, 6
... Air discharge port, 7 ... Piezoelectric fan, 70 ... Vibration plate, 71, 72 ... Piezoelectric bimorph element, 7
3, 74, 75, 76... Electrode, 77... Lead wire, 78... Electrode plate, 8... Support, 81...
Groove, 90...adhesive.

Claims (1)

[Scope of Claims] 1. In a piezoelectric fan device in which a piezoelectric fan using a piezoelectric bimorph element is supported by a support and housed in a casing, the support is formed into a hollow cylinder, and an axis is attached to the peripheral wall of the cylinder. The piezoelectric fan and the support body are integrated by providing two grooves facing each other in the direction, fitting and supporting the piezoelectric fan in the grooves, and providing an adhesive means in the hollow cylindrical body. Features a support structure for piezoelectric fans. 2. A support structure for a piezoelectric fan according to claim 1, wherein the hollow cylinder is a square cylinder. 3. A support structure for a piezoelectric fan according to claim 1, wherein the hollow cylinder is a cylinder. 4. The piezoelectric fan support structure according to claim 1, wherein the hollow cylinder is an elliptical cylinder. 5. The support structure for a piezoelectric fan according to any one of claims 1 to 4, wherein the hollow cylindrical body is integrally formed with a casing.