JPH0466160B2 - - Google Patents

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention comprises an electrostrictive element sandwiched between a pair of metal blocks consisting of a front plate and a backing plate, and an ultrasonic irradiation surface that operates on a long and narrow area. The present invention relates to a Langeyuvent type vibrator.

``Prior art'' One disk-shaped electrostrictive porcelain plate is directly connected, or a plurality thereof is connected mechanically in series and electrically in parallel via a terminal plate to form an electrostrictive element, and both main surfaces thereof Languevain-type transducers, which are stacked and fixed by a pair of metal blocks placed on top of each other, are widely used in devices that use various types of ultrasonic transducers, but conventional ones have a cross-section of a pair of metal blocks and an electrostrictive element. Because the shapes were the same, the acoustic load was too light and the loss was sometimes large. Furthermore, among metal blocks, one is known in which the diameter of the front end face of the front plate, which is irradiated with ultrasonic waves, is increased in diameter in a trumped shape to increase the irradiation area, but this also inevitably causes loss.

``Problem to be solved by the invention'' One of the metal blocks, which has a height that is an integral multiple of λ/2 and has a prismatic shape that is long in the horizontal direction, is used as a front plate that irradiates vibrations forward, and its longitudinal axis , an electrostrictive element and another metal block called a backing plate are laminated on one or more concave seating surfaces formed by cutting out in a direction perpendicular to the horizontal axis so as to be flush with the upper end surface of the front plate. , and the front plate is long and has a height that is an integral multiple of λ/2 facing the concave seating surface in the direction perpendicular to the horizontal axis that seats the laminate of the electrostrictive element and the backing plate. If the length of the portion is large, a through hole is bored in the facing portion in a direction perpendicular to the long axis.

``Function'' One of the metal blocks and the front plate are made into a horizontally long prismatic shape to apply an appropriate acoustic load to the electrostrictive element. By setting this, the propagation of ultrasonic vibrations to be irradiated forward in the horizontal axis direction is blocked.

``Example'' (1) Figure 1 shows the basic aspect of the Languevin type vibrator of the present invention, in which 1 is made of a lead titanate zirconate compound, and both main surfaces are coated with silver or the like. A pair of polarized plate electrostrictive elements 11, 11 forming metallized electrode surfaces (not shown)
are made of a thin metal plate, and are connected mechanically in series and electrically in parallel via a terminal piece 12 having a tongue-shaped conductive part 12a protruding from the outer periphery to be connected to the lead wire L, on the terminal piece 12 side. The positive polarity side of the electrostrictive element is bonded with an adhesive, and 2 is one metal block serving as a front plate, preferably having a width approximately equal to the outer diameter of the electrostrictive element, and having a width at the center in the horizontal axis direction. In the direction perpendicular to the horizontal axis, the upper end surface of the laminate of the electrostrictive element 1 and the other metal block 3 serving as the backing plate is placed on both sides of the front plate having a height that is an integral multiple of λ/2. A concave seating surface 22 of a depth that is positioned and seated on the same surface as the end facing portions 21, 21 of the laminate, and grooves 23, 23 that are deeper than the concave seating surface 22 in a direction perpendicular to the horizontal axis. are engraved to form the electrostrictive element 1 and opposing parts 2 at both ends of the front plate.
1 and 21, and blocks the propagation of ultrasonic vibrations to be radiated forward from the electrostrictive element 1 in the horizontal axis direction.

(2) In Fig. 2, 1 is a pair of electrostrictive elements 11,
11, and a terminal plate 12 having a terminal portion 12a protruding from the outer periphery for connecting the lead wire L; 3 is an electrostrictive element perpendicular to the horizontal axis, which is perforated in the center of the front plate 2 in the horizontal axis direction; A backing plate that is laminated and bonded to the electrostrictive element 1 on the concave seating surface 22 in the direction;
Both ends 2 of the front plate facing the laminate
Grooves 23 and 23 deeper than the concave seating surface 22 that maintain insulation from the electrostrictive element 1 are cut between the grooves 1 and 21, and these configurations are exactly the same as in the previous example, but in this example, The front plate 2 is made longer in the horizontal axis direction, and the facing parts 21, 21 formed at both ends thereof are made longer, respectively, through the laminate of the electrostrictive element 1 and the backing plate 3, and the deep grooves 23, 23. , in the case where the long axis dimension of the front plate 2 is increased by providing through holes 21a, 21a in a direction perpendicular to the horizontal axis in the portions of the opposing parts 21, 21 that correspond to nodes of vibration propagating in the lateral direction. This blocks vibrations that propagate in the lateral direction and cause waviness to the irradiated surface of the front plate.

(3) Figure 3 shows a plurality of concave seating surfaces 2 at the center and both ends of the front plate 2, which is elongated with a height that is an integral multiple of λ/2 in order to increase the output.
2, 22' and 22'', each pair of electrostrictive elements 1
Three sets of electrostrictive elements 1 consisting of terminal plates 12, 12' and 12'' having conductive parts 12a, 12'a and 12''a; , 1' and 1'' and backing plates 3, 3' and 3'' are manufactured in the same manner as in the previous example, and the upper end surfaces of the laminated backing plates 3, 3' and 3'' are an integer of λ/2 of the front plate. Set equal to twice the height, λ/2
As before, deep grooves 23,
The facing part 21 of the front plate formed through 23,
Through-holes 21a, 21 in the direction perpendicular to the horizontal axis are formed in the portion corresponding to the node of vibration propagating in the horizontal direction in 21.
A is provided to block vibrations that propagate in the lateral direction and cause waviness to the irradiated surface of the front plate.

In this example, electrostrictive elements 3', 3'' and backing plates 3', 3'' are laminated and fixed on concave seating surfaces 22', 22'' formed at both ends of the front plate 2 in the horizontal axis direction. However, in order to give sufficient acoustic load to these electrostrictive elements 3', 3'', the electrostrictive elements 1', 1'' on the concave seating surfaces 22', 22'' at both ends of the front plate 2 and the backing plate 3 ', 3'', through grooves similar to the grooves 23, 23 of the front two examples, which are deeper than the concave seating surface (not shown), are provided with opposing portions 2 of the same two front examples with a height of λ/2.
The front plate 2 may be extended in the longitudinal direction so as to form a facing portion corresponding to either one of the front plate 2 and the front plate 2 .

In all examples, the electrostrictive element consisting of a pair of electrostrictive elements and a terminal plate and the backing plate are fixed to the front plate by laminating them with an adhesive, but as shown in FIG. 4A, The electrostrictive element 1 is an annular body consisting of annular piezoelectric elements 11, 11 and an annular terminal plate 12, and protrudes downward from the backing plate 3. , a screw hole 22 drilled in the concave seating surface 22 of the front plate 2 through which an insulating tube 4 made of plastic or the like is inserted.
A bolt-fastening structure may be provided by a screw rod 3a screwed into the screw rod 3a, or, conversely, a screw rod 22b protruding from the concave seating surface 22 of the front plate 2 and the backing plate 3
In addition to bolting the electrostrictive element 1, which has an annular shape and has an insulating means 4 such as an insulating tube in the center hole, through the screw holes 3b protruding from the front plate and the backing plate, although not shown, A counterbore is formed on the outer end surface, and a bolt head and a nut are inserted through the concave seating surface of the front plate, the electrostrictive element, and the center hole of the three backing plates, and are seated in the counterbore. There are various means for fixing the above three parts, such as the possibility of fastening them with a tightening bolt, and when using another tightening bolt or using the above-mentioned adhesive, the outer cross section of the three parts can be fixed. The rectangular shape facilitates machining of the concave seating surface of the front plate.

In addition, as mentioned above, the height from the upper end surface of the front plate and the backing plate laminated together with the electrostrictive element on the concave seating surface of the front plate to the irradiation surface of the front plate is an integral multiple of λ/2. The dimensions of other parts in the height (thickness) direction are not particularly specified, but the center of the electrostrictive element in the thickness direction is 1/2 of an integral multiple of the above λ/2.
It is desirable that it be located in part 2.

"Effects of the Invention" Since the Languevent type vibrator of the present invention is configured as described above, it can be used as an ultrasonic vibrating device for a long and narrow area and transmits the acoustic load of the electrostrictive element to the front plate without wasting the irradiation area. In addition, when the front plate is made particularly long, an opposing portion extending long in the transverse direction formed by a laminate of the electrostrictive element and the backing plate on the concave seat surface of the front plate and a deep groove is attached. The propagation of vibration in the direction of the horizontal axis is blocked by a through hole bored in a direction perpendicular to the horizontal axis.Moreover, this hole is a through hole and is not cut out to either the upper or lower end surface, and is connected in a bridge shape. This makes it possible to uniformly irradiate ultrasonic waves from the irradiation surface without causing bending in this part, and furthermore, it is possible to arrange electrostrictive elements in parallel depending on the required output, so it is possible to apply various types of ultrasonic vibrations using ultrasonic vibration. It is particularly effective when used in cleaning tanks for rectangular tanks, or ultrasonic welders for welding long linear surfaces of plastics.

[Brief explanation of drawings]

Fig. 1 shows the basic aspect of the Languevent type vibrator of the present invention, Fig. A is a top view, Fig. B is a longitudinal cross-sectional view taken along line A--A in Fig. A, and Fig. 2 shows the front plate of Fig. 1. Figure A is a top view, Figure B is a vertical cross-sectional view taken along the Ro-Ro line in Figure A, and Figure 3 is a diagram showing another embodiment extended in the horizontal axis direction, and Figure 3 is a diagram showing another embodiment of the present invention in which a plurality of electrostrictive elements are installed together. Figure A is a top view, B is a top view, and Figure B is a top view.
The figure is a vertical cross-sectional view taken along the line H--H in Figure A, and Figures 4A and B are vertical cross-sections showing other methods of laminating and fixing an electrostrictive element and a backing plate on the concave seating surface of the front plate, respectively. It is a diagram. DESCRIPTION OF SYMBOLS 1... Electrostrictive element, 2... Front plate, 21, 21... Opposing part, 21a, 21a... Through hole, 22, 22... Concave seating surface, 3, 3... Backing plate.

Claims (1)

[Scope of Claims] A concave seating surface that has a height that is an integral multiple of 1λ/2, has a prismatic shape that is long in the horizontal direction, and is formed by cutting out a metal block that serves as the front plate in a direction perpendicular to the horizontal axis. Then, the electrostrictive element and the other metal block serving as the backing plate are laminated so as to be flush with the upper end surface of the metal block,
Langillepan type vibrator made by joining. 2. A concave seating surface is formed by cutting out a metal block in a direction perpendicular to the horizontal axis of one of the metal blocks, which will serve as the front plate, and has a height that is an integral multiple of λ/2 and has a prismatic shape that is long in the horizontal direction. The electrostrictive element and the other metal block that will serve as the backing plate are laminated so that they are flush with the top end surface.
Propagation of ultrasonic vibrations to be irradiated forward in the transverse axis direction to the part facing the above-mentioned laminate formed in the first metal block while bonding and maintaining the height of an integral multiple of λ/2. A Languevent type vibrator having a through hole perpendicular to the horizontal axis that blocks the horizontal axis. 3. Each of the plurality of concave seating surfaces, which have a height of an integral multiple of λ/2 and have a horizontally long prismatic shape, are cut out in a direction perpendicular to the horizontal axis of one of the metal blocks serving as the front plate. The electrostrictive element and the other metal block serving as the backing plate are laminated and bonded so that they are flush with the upper end surface of the metal block, and the height is maintained at an integral multiple of λ/2 to form the first metal block. A Languevent type transducer having a through hole in a direction perpendicular to the horizontal axis for blocking propagation of ultrasonic vibrations to be irradiated forward in the long axis direction, in a part facing the above-mentioned laminate formed in the above. .