JPS594791Y2 - Ultrasonic cleaning equipment - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an ultrasonic cleaning device used for cleaning pH measuring glass electrodes etc. installed in hazardous locations.

For explosion-proofing purposes, such cleaning equipment must always keep the temperature rise in the ultrasonic vibrating part below a certain limit, and must ensure that the vibrator is placed inside a protective container (pressure-resistant container). Ru.

However, when the ultrasonic vibrating section is not immersed in liquid (cleaning liquid), excessive amplitude and self-heating cause a temperature rise that may even damage the vibrator.

Furthermore, it is not uncommon for holes to form in the protective container due to corrosion or the like.

Therefore, unless an ultrasonic cleaning device takes these cases into consideration, it cannot be said to be safe for use in hazardous locations.

There are no conventional devices that take these points into consideration.

An object of the present invention is to provide an ultrasonic cleaning device configured to quickly detect an excessive temperature rise in an ultrasonic vibrating part or a hole in a protective container to prevent accidents from occurring.

The present invention will be explained in detail below using the drawings.

FIG. 1 is a mechanical configuration diagram showing an embodiment of an ultrasonic cleaning device according to the present invention.

In the figure, 1 is a cylindrical vibrator, and 2 and 3 are circular insulating plates made of epoxy resin or the like bonded to both bottom surfaces of the vibrator 1.

A ring-shaped conductive metal film 21 is formed on the exposed surfaces (other than the adhesive surfaces) of the insulating plates 2 and 3, that is, the surfaces near the outer periphery.
．． 31 is formed by etching or the like.

This metal coating 21.31 is electrically short-circuited.

41. Denoted at 51 is a metal plate bonded to the insulating plates 2 and 3, and 61 is a metal cylinder.

The metal plates 41.51 and the metal tube 61 are welded at their joints, and these metal plates 41.51 and the metal tube 61 form the protective metal container 4 as a pressure-resistant container.

Reference numeral 7 denotes a temperature sensing element such as a thermistor, which is connected between the metal film 21 and the metal plate 5.

8 is a metal pipe welded to the metal cylinder 6, and 9 is a lead wire passed through the pipe 8.

This lead wire 9 consists of a wire for sending power to the vibrator 1 and a wire for sending temperature signals and the like.

10 is a cutoff circuit that stops supplying power to the vibrator 1 in the event of an abnormality, and 11 is a power supply section.

Note that the vibrator 1. The combination of the insulating plates 2, 3 and the metal container 4 is placed in a liquid and forms an ultrasonic vibrating section.

Further, the metal film 21.31 functions as one electrode, and the metal container 4 functions as the other electrode.

The electrical configuration of the ultrasonic cleaning apparatus shown in FIG. 1 is shown in FIG. 2 (corresponding parts to those in FIG. 1 are given the same reference numerals).

In the figure, Rr represents the resistance between the electrodes (between the metal film 21.31 and the metal container 4), and Rt represents the resistance of the temperature sensing element 7.

In this embodiment, these resistors Rr and Rt are connected to form a parallel circuit.

Further, the cutoff circuit 10 includes a relay RL that opens and closes a power supply line to the vibrator 1, and a transistor Tr that drives the relay RL.

The power supply unit 11 is a power supply V for supplying power to the vibrator 1.
a, and a DC power supply Vd for driving relay RL and the like.

One end of a relay RL is connected to the collector terminal of the transistor Tr, and an output voltage of a power supply Vd is applied between the other end of the relay RL and the emitter terminal of the transistor Tr.

Furthermore, the base current of the transistor Tr is the resistance Rr,
It is determined by the combined resistance value of the parallel circuit made up of Rt.

Next, the operation of the above embodiment will be explained.

In a normal case where the temperature of the vibrator 1 is low and there are no holes in the metal container 4, the resistances Rt and Rr are sufficiently large.

Therefore, the base current of the transistor Tr flowing through these resistors Rt and Rr is small, and the transistor T
r is in a cutoff state, and the power supply line to the vibrator 1 is closed.

On the other hand, if there is a large temperature rise in the vibrator 1 for some reason, the value of the resistor Rt decreases, the base current of the transistor Tr increases, and the transistor Tr becomes conductive.

Therefore, the relay RL operates, the power supply line to the vibrator 1 is opened, and the temperature rise is suppressed to below a certain value.

Also, if the metal container 4 has a hole, the cleaning liquid etc. will leak into the metal container 4.
flows into the transistor T, the value of the resistor Rr decreases, and the transistor T
r becomes conductive.

Therefore, in this case as well, the power supply line to the vibrator 1 is opened and safety is maintained.

After all, no dangerous situation will occur due to the temperature rise of the vibrator 1 or the presence of holes in the metal container 4.

In the above description, a thermistor-like element is shown as the temperature-sensitive element, but a bimetal or the like may also be used.

In this case, it is necessary to connect a resistor in series with the bimetal to determine the base current value to a constant value.

Not only when using this bimetal, the resistors Rr, R
By connecting a resistor in series or parallel to t, the base current can be set to an appropriate value.

As explained above, the present invention connects the inter-electrode resistance and the temperature-sensitive element resistance in parallel, and is configured to stop supplying power to the vibrator when the combined resistance of this parallel circuit becomes less than a certain value. This solves the explosion-proof problem.

According to the present invention, it is possible to realize an ultrasonic cleaning device with a simple configuration that can prevent accidents from occurring.

[Brief explanation of drawings]

FIG. 1 is a mechanical configuration diagram showing an embodiment of the ultrasonic cleaning device according to the present invention, and FIG. 2 is an electrical configuration diagram of the device shown in FIG. 1. 1... Vibrator, 2, 3... Insulating plate, 4
...Metal container, 7...Temperature sensing element, 8.
...Pipe, 9...Lead wire, 10...
...Break circuit, 11...Power supply section.

Claims (1)

[Claims for Utility Model Registration] A pair of electrodes and a temperature sensing element whose resistance value decreases as the temperature rises are arranged in an ultrasonic vibrating section, and the combined resistance of the inter-electrode resistance and the temperature sensing element resistance is constant. In an ultrasonic cleaning device that uses a cutoff circuit to stop power supply to the ultrasonic vibrating section when the voltage drops below this value, a cylindrical vibrator is used and both bottoms of the vibrator are protected through insulating plates. An ultrasonic vibrating section is constructed by fixing the metal container to a metal container for use, with the metal container serving as one electrode and the metal film formed on a part of the exposed surface of the insulating plate serving as the other electrode. A relay for connecting a temperature sensing element to the ultrasonic vibrating section and a transistor for driving the relay and a transistor for driving the relay form the above-mentioned cutoff circuit, and the base current of the transistor is An ultrasonic cleaning device characterized in that the ultrasonic cleaning device is configured to be determined by a combined resistance value of a parallel circuit including an electrode and the temperature sensing element.