JPH03171898A - Manufacture of ultrasonic sensor - Google Patents

Abstract

PURPOSE:To stabilize effective performance by forming an ultrasonic sensor by arranging members of different sound impedance into plural layers on the mechanical energy emitting surface side of a transducer while allotting order to an impedance value. CONSTITUTION:Paste mixed with material whose impedance is low as a filler itself sufficiently by rate equal to the transducer or higher rate is produced as the material of a first layer having the impedance Z1 close to the transducer, and this paste is coating-processed by a printing method or so as to make uniform thickness at the place of a prescribed shape, and is cure-processed beforehand to some extent not to cause deformation. Next, the layers L2...Ln are formed in such a way that a second layer is placed on the first layer... and n-th layer and so on. Then, an obtained impedance matching multiplayer between the transducer and a medium is out as shown by a dot line, and is joined to the side of the transducer to emit the mechanical energy, and the ultrasonic sensor is obtained. Thus, the stabilization of the performance can be attained.

Description

[Detailed description of the invention] (Fields of industrial use) The present invention relates to an ultrasonic sensor.

(Conventional technology) A polymer-based material such as a recon resin mixed with a metal powder close to the impedance of the transducer as a filler is placed on the surface of the transducer, and the resin is gently cured. It was common knowledge that the degree of distribution of the filler should be high on the transducer side and low on the medium side. It is sometimes very difficult to completely cure the resin, and as a result, it is not possible to provide a stable ultrasonic sensor as a product.

(Problems to be Solved by the Invention) The purpose of the present invention is to stabilize the manufacturing process of ultrasonic sensors, and in particular, to stabilize the manufacturing process of ultrasonic sensors. Alternatively, it is intended to stabilize the effective performance by preventing variation and deterioration due to mismatching of acoustic impedance due to water or the like.

As is well known, the cause of the impedance mismatch is the considerably large difference in acoustic impedance between the transducer and the medium, and to prevent this, layers with impedance matching functions should be It is also well known that it is a good idea to place the

However, there is no concrete way to properly match these L<. As mentioned above, this was done using extremely primitive means.

(Function) In the present invention, the vertical axis in FIG. 1 shows the acoustic impedance VLz of the transducer and the medium, and the horizontal axis shows their ff! The average impedance Z,...Z. is shown as a model.

Each layer L, ~L. acoustic impedance ZI~Z,
The observation of t-+lI! as a component of the layer material. 1 is near the transducer, and L. shall include air bubbles containing the medium in order to make it appear similar to the medium.

■,1~ of these layers! , 7, first, the impedance Z near the transducer side of the first layer is
As a material having I, a paste is prepared by sufficiently mixing a material with a low impedance equivalent to that of the transducer, or even higher than that of the filler itself, and this paste is printed or applied to a predetermined shape with a uniform thickness. Coating treatment is applied so that it becomes , and then curing treatment is performed to a degree that does not cause deformation.

Next, as shown in the perspective view in FIG. 2, a second layer . . . The impedance matching multi-layer between the transducer and the medium thus formed is cut as shown by the dotted line in the figure, and is then attached to the layer m1 for irradiating the mechanical energy of the transducer, as shown in FIG. An ultra-a wave sensor as shown in the vertical cross-sectional view is obtained.

(Example) Into the paste based on silicone material (one piece of ceramic filler equivalent to the transducer is added, and the mixing ratio is ordered from the first layer's fine components to the lowest ratio) , and screen-print each prepared paste I1 (generally n is 10 types or less) sequentially from IR4; after the first layer is cured, print the second layer,
Also, after the second layer was cured, the next layer was printed on top of it.

The acoustic impedance matching member of the present invention is fabricated by repeating the steps in step 2 n times.

Of course, in order to shorten the production time, f-stages, etc. in which the odd-numbered layers are printed on a separable support base in advance and the even-numbered layers are overlapped by using an adhesive that also functions as an adhesive, etc., belong to the scope of the present invention. It is something.

The impedance matching member obtained in this way is bonded to the mechanical energy emitting surface of the transformer 5' user and grooves are formed in the ultrasonic sensor, making it possible to arbitrarily manufacture each layer having a generally stable impedance. In order to be
It has industrial value.

[Brief explanation of the drawing]

FIG. 1 shows the impedance values. Second
The figure shows an impedance matching member in a perspective view. FIG. 3 shows an example of the present invention in cross-section.

Claims (2)

[Claims] (1) A method for manufacturing an ultrasonic sensor, characterized in that members having different acoustic impedances are formed in multiple layers on the mechanical energy emitting surface side of the transducer, with the impedance values arranged in order. (2) A method for manufacturing an impedance matching member, characterized in that the method for forming layers having different impedance values as claimed in the claims is performed by multiple printing methods or coating methods.