JPS6034914B2 - ultrasonic transducer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ultrasonic vibrator for use in, for example, an inhaler.

The conventional support structure between the horn and the supporting odor 3' is as shown in FIG.

That is, the horn is formed into a cylindrical shape with a horn small diameter part la at the tip and a horn large flea part lb at the base. The inner surface of the curved plate 16 is brought into contact with the stepped portion 15 and the bent plate 16.
was welding. FIG. 3 shows another conventional example, in which a support hole 18 is formed near the end of the outer peripheral surface of the large horn portion lb, and the support hole 18 is inserted into the outer circumference of the support 3'. Insert the support screw 17 from the surface and attach the horn to the support 3.
′ was fixed. However, if it takes 100~
As the frequency becomes higher than 300 KHZ, the resonant wavelength becomes shorter, and the length of the horn to match this wavelength is 17~
It will have 6 ribs.

As a natural result, the mass of the horn also decreases by 4.
If the method of supporting the horn is poor, the efficiency will be significantly reduced. That is, ideally, the efficiency will be improved if the support object of the support 3' and the horn 1 are in contact with each other at a point or a line at a node of vibration of the horn 1. In contrast to this principle, the method of fixing the horn and the support holder 3' shown in FIGS. 2 and 3 involves surface contact, resulting in poor efficiency. Furthermore, the horn 1 that operates at a high frequency is made smaller as described above, and is necessarily required to have high dimensional accuracy. In order to make electrical appliances for household use, it is required that such horns can be industrially produced in large quantities at low cost. Furthermore, in the method of fixing the horn 1 and the support 3' as shown in FIG. 3, there is a problem that machining the support hole 18 becomes a bottleneck in terms of cost and precision when downsizing the horn. was there. The present invention has been provided in view of the above-mentioned points, and by providing a full circumference that can accurately support the vibration nodes of the horn and is easy to process, efficiency can be improved without disturbing the resonance of the horn. The purpose is to provide a good ultrasonic transducer.

Embodiments of the present invention will be described in detail below with reference to the drawings. In FIGS. 4 and 5, reference numeral 1 denotes a metal horn consisting of a small horn part la and a large horn part lb, similar to the subsidiary example. 3
is a support for supporting and fixing the horn, and this support 3 is cylindrical and has a flange 1 in the circumferential direction on its inner peripheral surface.
9 is formed.

Further, the flange 9 has three triangular supporting plates 20 projecting toward the center thereof, and the supporting plates 20 become thinner and sharper toward the tip to form an edge portion 4. 2
is a circumferential groove with an open circumferential surface cut across the entire circumferential surface of the stepped portion 15 side of the large horn portion lb, and this circumferential groove 2 is formed in a V-shape, and as will be described later. The position of the circumferential groove 2 is
It is installed at the vibration node where the sound vibrates.

The edge portion 4 of the support plate 20 of the support 3 is in point contact with this circumferential groove 2 and saddle-attached, thereby fixing the horn 1 to the support 3. The contact between the circumferential groove 2 and the edge portion 4 may be not only the above point contact but also a line contact. An example of an inhaler using an ultrasonic vibrator configured as described above is shown in FIG.
In the figure, 5 is a cylindrical tank with an open top.
A heater 6 is buried in the lower part of the tank 5 , and a connector 7 as an electrode of the positive and negative heaters 6 connected to the heater 6 is provided to protrude from the lower surface of the tank 5 . Reference numeral 9 denotes an insulator for insulating and separating the positive and negative connectors 7.

A heater power source 8 is connected to the connector 7, and the suction water 10 stored in the tank 5 is heated by the heater 6. 11 is a cap screwed onto the top of the tank 5.

A tubular water absorbing body 12 is attached to the cap 11 so that the cap 11 is inserted into the tank 5 to suck up intake water 10 from the tank 5. A is the ultrasonic transducer main body, and this ultrasonic transducer main body A
are a vibration element 13 that generates a high frequency, and a vibration element 13
It consists of a metal horn that vibrates at a high frequency, and a support 3 that supports and fixes the horn and the vibrating element 13. Reference numeral 14 denotes a high frequency power source for exciting the ultrasonic transducer main body A.

The tip of the water absorbing body 12 is arranged as shown in the figure, with the tip of the water absorbing body 12 in contact with the tip of the horn. In this way, the suction water 10 heated by the heater 6 in the tank 5 is sucked up by the capillary phenomenon of the water absorbent body 12, and the suction water 10 is atomized from the tip of the water absorbent body 12 by the vibration of the horn 1, and this mist is generated. It is inhaled into the oral cavity. By the way, FIG. 7 shows the vibration form of the step type vibrator.

The vibration mode of the horn in its free state is as shown in Figure 7a, and the vertical displacement of the horn is larger at the tip than at the root, increasing the amplitude, as shown in Figure 7b. ing. There is a node (point A in the figure) almost in the center where the horn 1 does not vibrate. The position of this node varies depending on the length, diameter, material, etc. of the small horn part la and the large horn part lb. FIG. 6 shows another embodiment of the support plate 20 of the support smell 3, in which the support plate 20 is bent into a substantially S-shaped cross section, and has elasticity in the axial direction of the horn and in the direction perpendicular to the axial direction. The horn is supported by a plate 20, which further improves vibration efficiency. Although the step-shaped horn as in the embodiment mainly vibrates longitudinally in the axial direction, it also undergoes slight expansion and contraction deformation in directions perpendicular to the axial direction. In the above-mentioned small horn that operates at a high frequency of 100 to 300 KHZ, it is desirable to minimize the restraint between the horn and the support plate 20 of the support 3 as much as possible, not only in the axial direction but also in the direction perpendicular to the ball direction. It is better to reduce the vibration restraint in the direction in which the shaft is moved, and in this respect, it is desirable to use a thin support plate with ballistic properties as in this example, and to use a support structure that also takes elasticity and elasticity into consideration in the direction orthogonal to the axial direction. It is. Therefore, the position of the vibration node and the support part of the horn 1 is
Even if the horn is slightly shifted due to variations in size, material, etc., the vibration is not attenuated by supporting it with an elastic support plate. As mentioned above, the present invention
A circumferential groove with a closed circumferential surface is cut in a portion of the outer circumferential surface corresponding to the vibration node of a substantially cylindrical horn that is vibrated by ultrasonic waves, and the edge portion of the support plate for supporting and fixing the horn is cut as described above. Since the support plate is iron-supported in the circumferential groove, the contact between the edge of the support plate and the horn can be made into a point or line at the vibration node of the horn, improving vibration efficiency and producing large displacement with small power. In addition, since the support structure of the horn is a circumferential groove, the horn can be easily processed using the same lathe that is used to process the entire horn, and it is also possible to manufacture small horns in large quantities at low cost. In order to achieve this, machining using an automatic lathe is preferable, and a structure having a substantially cylindrical shape with a circumferential groove provided on its outer circumferential surface has the advantage that it can be easily manufactured with high precision using only lathe machining.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram showing an example of an inhaler using an ultrasonic vibrator, Fig. 2 is a vertical cross-sectional view showing a support structure of a conventional horn and a supporting odor, and Figs. FIG. 4 is a longitudinal sectional view showing the support structure of the horn and the support of the beautiful example of the present invention; FIG. 5 is a horizontal sectional view of the same; FIG.
The figure is a sectional view of a main part of another embodiment same as the above, and FIGS.
3 is a circumferential groove, 3 is a support plate, 4 is an edge portion, and 2 is a support plate. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7

Claims (1)

[Scope of Claims] 1. A circumferential groove with an opening on the circumferential surface is cut in a portion of the outer circumferential surface corresponding to the vibration node of a substantially cylindrical horn vibrated by ultrasonic waves,
An ultrasonic transducer comprising an edge portion of a support plate of a support for supporting and fixing a horn, which is fitted and supported in the circumferential groove. 2. The ultrasonic transducer according to claim 1, wherein the support plate has elasticity in the axial direction of the horn and in a direction perpendicular to the axial direction.