JPH05146756A - Ultrasonic diaphragm - Google Patents

Abstract

PURPOSE:To improve the conversion efficiency and acoustic characteristic in the diaphragm for the ultrasonic wave transmitter-receiver by laminating plural polyester films having a specified thickness to form the diaphragm. CONSTITUTION:Plural polyester films having <=100mum thickness are laminated to form an ultrasonic diaphragm 1. The diaphragm 1 is placed on the upper surface of the housing 2 of an ultrasonic transmitter-receiver, the peripheral upper surface of the diaphragm 1 is pressed by a cover 4 through a packing 3 and fixed, and an ultrasonic vibrator 6 is fixed to the surface and used. In this constitution, an electric signal is imparted to the vibrator 6 which is mechanically vibrated, the equivalent mass is reduced to <=1/10 since the diaphragm 1 is made of a thin polyester film as compared with the metallic diaphragm, the supporting and holding power as well stiffness are decreased, and the send- and-receive sensitivity is improved. Besides, the transversal wave is nor generated, and the vibration is transmitted to the supporting member and not dissipated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used in an ultrasonic cleaner, an ultrasonic atomizer, an ultrasonic irradiator and an ultrasonic wave transmitter / receiver to transmit vibrations to the air and receive the waves. The present invention relates to a sound wave diaphragm.

[0002]

2. Description of the Related Art An ultrasonic vibration plate for transmitting and receiving ultrasonic waves is provided in the power source of the conventional equipment. In this type of ultrasonic diaphragm, a metal such as tantalum, titanium, aluminum, and stainless is used, and as shown in FIG. 3, the ultrasonic diaphragm C is placed on the upper surface of the housing A via the packing 3, Press the outer periphery of the ultrasonic diaphragm C through the packing B with the governor D, and tighten with the bolt E to fix it.
The ultrasonic diaphragm F is fixed to the back surface of the ultrasonic diaphragm C.

Although the ultrasonic diaphragm C has a high mechanical strength, vibration is transmitted to the entire diaphragm, the radiated electric power is reduced, and the ultrasonic vibration is damped by stiffness and compliance, so that the electric-mechanical-acoustic efficiency is increased. Low. Also, the dumping time is long. Furthermore, in the case of a liquid contact structure, the durability against erosion and chemicals generated by vibration and flow is weak,
There is a drawback that it cannot be used in the precision field where the yield rate of products decreases unless rust, metal ions and dust are removed, or in the sensor field that requires a transducer with high sensitivity and low tamping property.

Therefore, an ultrasonic vibrating plate made of a synthetic resin such as polyvinyl chloride or polyvinylidene fluoride has come to be used.

[0005]

However, even with the synthetic resin, since the equivalent mass and supporting force are large, the load is large, and the transverse wave vibration propagation and the damping time are long, the acoustic conversion efficiency and other factors are high. There was a problem that the acoustic characteristics were poor and the acoustic impedance did not match the load.

In view of the above, it is an object of the present invention to provide an ultrasonic diaphragm which can significantly reduce the above problems and improve the conversion efficiency and acoustic characteristics.

[0007]

In order to solve the above-mentioned problems, the present invention comprises an ultrasonic diaphragm made of polyester film. Also, a plurality of polyester films are stuck together. And the polyester film is 100 μm
Use the following:

[0008]

The present invention is constructed as described above, and by attaching an ultrasonic vibrator to one side and supplying an electric signal to the ultrasonic vibrator, it is converted into electro-mechanical vibration to form an ultrasonic vibration plate. Transmitted. The mechanical vibration generated by the ultrasonic diaphragm is radiated into the air or liquid. On the contrary, the vibration wave in the air or the liquid is received and transmitted to the ultrasonic transducer.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described in detail with reference to FIG. 1. In this embodiment, an ultrasonic vibration plate 1 made of polyester film is used as a wave transmitter / receiver on the upper surface of a housing 2. The ultrasonic vibration plate 1 is placed, and the outer peripheral upper surface of the ultrasonic vibration plate 1 is pressed by the governor 4 through the packing 3 and fixed by a plurality of bolts 5.
In addition, reference numeral 6 in the drawing denotes an ultrasonic vibrator fixed to the lower surface of the ultrasonic diaphragm 1. If the thickness of the ultrasonic diaphragm 1 is 100 μm or less, the conversion efficiency and acoustic characteristics are particularly improved.

The first embodiment is constructed as described above, and when an electric signal is supplied to the ultrasonic vibrator 6, it is converted into electro-mechanical vibration and transmitted to the ultrasonic diaphragm 1. Since the ultrasonic vibration plate 1 is a thin polyester film and has an equivalent mass of 1/10 or less as compared with metal, this mechanical vibration has a small supporting and holding force, a small stiffness, and a high transmission / reception sensitivity. Moreover, there is no transverse wave vibration and no radiation other than the effective radiation of the ultrasonic oscillator is transmitted, and it is possible to effectively transmit and receive waves without transmitting vibrations to the supporting members such as the housing, bolts, packing, etc. ..

Next, a second embodiment will be described with reference to FIG. 2. In this embodiment, two polyester films are attached with an adhesive. It should be noted that any number of sheets can be polymerized as long as the acoustic characteristics are not deteriorated depending on the strength. In the figure, the same parts as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

The present invention is not limited to the above embodiment, but can be used in various ultrasonic cleaners, ultrasonic atomizers, ultrasonic irradiators and ultrasonic transmitters / receivers.

[0013]

The present embodiment has the above-described structure and action, and since the ultrasonic vibration plate is made of polyester film, it has extremely strong durability against heat and chemicals and causes erosion. Is almost negligible, and the electrical insulation is excellent and stable. Further, since it is a thin film with no electrolytic corrosion, rust and dust, it has advantageous characteristics with almost no acoustic loss. Further, since the equivalent mass is 1/10 or less as compared with metal, the supporting and holding force is small and the transmission / reception sensitivity is high. Further, since there is no transverse wave vibration and no radiation other than the effective radiation of the ultrasonic transducer is performed, it is possible to effectively transmit and receive waves without transmitting vibrations to various supporting members and causing no loss. ..

In particular, if the thickness is 100 μm or less, the equivalent mass and supporting force are significantly reduced, and the conversion efficiency and acoustic characteristics can be improved. Also, due to the strength, even if a plurality of sheets are polymerized, the result is not extremely lowered.

[0015]

[Brief description of drawings]

FIG. 1 is a sectional view of a first embodiment of a wave transmitter / receiver using an ultrasonic vibration plate according to the present invention.

FIG. 2 is a sectional view of a second embodiment.

FIG. 3 is a sectional view of a conventional example.

[Explanation of symbols]

 1 Ultrasonic Vibration Plate 2 Housing 3 Packing 4 Cover 5 Bolt 6 Ultrasonic Transducer

Claims (3)

[Claims] 1. An ultrasonic diaphragm made of a polyester film. 2. An ultrasonic vibrating plate constituted by laminating a plurality of polyester films. 3. The ultrasonic diaphragm according to claim 1, wherein the polyester film has a thickness of 100 μm or less.