JPS6010706Y2 - magnetostrictive vibrator - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a magnetostrictive oscillator that expands the radiation range of ultrasonic waves by improving the arrangement of DC magnetization bias magnets.

Normally, when a magnetostrictive vibrating element is driven with a high-frequency current, by applying a direct current magnetization bias, the center of the alternating current magnetic field can be moved to a range with good magnetostrictive efficiency, and an efficient magnetostrictive effect can be achieved.

Currently, π-type ferrite vibration elements are often used as magnetostrictive vibration elements, and magnets are used for biasing DC magnetization.

By the way, the conventional magnetostrictive vibrator, as shown in Fig. 1,
A plurality of vibration elements 2 are mounted on a vibration plate 1 made of one metal plate.
In order to generate the same vibration in all the vibrating elements 2 by arranging them in each row, DC magnetization bias magnets 3 are interposed at the ends of the vibrating legs 4 with their polarities aligned in the same direction. , is driven by passing a high frequency current through the excitation winding 5.

Note that even if the polarity of the magnet 3 is reversed, since the winding direction of the excitation winding 5 is reversed, this is essentially the same as aligning the polarity of the magnet 3 in the same direction.

Therefore, when a plurality of vibrating elements 2 are excited in the same direction, they vibrate in almost the same direction even if there is slight variation among the vibrating elements 2. Therefore, as a vibration system including the diaphragm 1, a simple vibration In the sound field, highly directional ultrasonic waves 6 as shown in FIG. 2 are emitted.

Therefore, for example, when the magnetostrictive vibrator is used in an ultrasonic cleaning device, the strong directivity means that strong ultrasonic waves can be obtained on the - side, but on the other hand, the radiation range of the ultrasonic waves becomes narrow, which reduces the cleaning effect. Some parts are there and others are not, resulting in uneven cleaning.

In addition, if an attempt is made to prevent uneven cleaning, more power than the ultrasonic energy required per unit volume must be supplied, which has the disadvantage of requiring a large number of vibrating elements 2.

This invention takes the above points into consideration and provides a magnetostrictive vibrator that has a wide ultrasonic radiation range and provides even ultrasonic effects without increasing the number of vibrating elements.

Next, this invention will be explained in detail with reference to FIGS. 3 and 4 showing one embodiment thereof.

In FIG. 3, 7 is a diaphragm made of a single metal plate such as a thin stainless steel plate, 8 is a large number of oscillating elements arranged in each row on the diaphragm 7, and 9 is the oscillating element 8. The excitation winding 11 wound around the vibrating leg 10 is interposed at the end of the vibrating leg 10 so that each row of the vibrating elements 8 has the same polarity and each row of the vibrating element 8 has an opposite polarity. This is a magnet for DC magnetization bias.

Therefore, since the polarity of the DC magnetization bias magnets 11 is alternately reversed for each row of the vibration elements 8 arranged in parallel on the vibration plate 7, the direction of the DC magnetization bias is reversed, and the magnetostrictive effect is reduced. Since the efficient excitation direction is reversed, the vibration state is reversed for each row, and the vibration system including the diaphragm 7 exhibits a complex vibration state rather than a single vibration state, as shown in Figure 4. As shown, weakly directional ultrasonic waves 12 are emitted, the range of cleaning effects is expanded, and uneven cleaning is reduced.

As described above, according to the magnetostrictive vibrator of this invention, by reversing the polarity of the DC magnetization bias magnet each time each row of vibrating elements intersects, the radiation range of ultrasonic waves is expanded and the ultrasonic effect is improved. The coverage area becomes wider and radiation unevenness can be reduced.

Therefore, ultrasonic waves having a radiation effect over a wide range can be emitted using a small number of vibrating elements.

[Brief explanation of drawings]

Fig. 1 is a front view of a conventional magnetostrictive vibrator, Fig. 2 is an explanatory diagram of the ultrasonic radiation range of Fig. 1, Fig. 3 is a front view of an embodiment of the magnetostrictive vibrator of this invention, and Fig. 4 is a front view of a conventional magnetostrictive vibrator. The figure is an explanatory diagram of the radiation range of the ultrasonic waves in FIG. 3. 8... Vibration element, 11... Direct current magnetization bias magnet.

Claims (1)

[Scope of utility model registration request] In a magnetostrictive vibrator in which a large number of vibrating elements each having a DC magnetization bias magnet are arranged in each row, the polarity of the DC magnetization bias magnet is reversed each time the arrangement of the vibration elements changes. A magnetostrictive vibrator featuring: