JPS5875311A - Ultrasonic solid state delaying medium - Google Patents

Abstract

PURPOSE:To suppress the spurious signals, by forming two slopes having prescribed angles to the two side faces which are parallel to each other to one of the two faces which are orthogonal to said two parallel side faces to install the input and output converting media on these two slopes and limiting the number of reflecting points of ultrasonic waves to each face. CONSTITUTION:The slopes E and F which have a groove G at a 90 deg. vertical angle and a 45 deg. angle to the faces C and D of a block-shaped delaying medium 100 are formed on the face opposite to a face B which is orthogonal to said faces C and D. The input and output converting media 200 and 300 are provided to the faces E and F respectively. For the transmitting route of the ultrasonic wave from the media 200 to the media 100, a reflecting point of the ultrasonic wave is set to the faces B, C and D respectively. At the same time, an absorbent 400 of ultrasonic wave is attached to a face A of the face opposite to the face B and excluding the slopes E and F as well as to ridge A' respectively so as to set the reflecting point at 0. Such delaying element is cut with a prescribed thickness to obtain a delaying medium 101 containing an absorbent 401 attached to each delaying element as well as input and output converting media 205 and 305. Then lead wires 206, 207, 306 and 307 are connected to the means 101 and media 205 and 305 to produce an ultrasonic solid state delaying medium.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an ultrasonic solid state retarder that suppresses spurious signals.

In general, an ultrasonic solid state retarder consists of (1) a delay medium made of glass, metal, crystal, tramic, etc. that propagates ultrasonic waves, and (2) lead zirconate titanate (piezoelectric laminate).
Alternatively, it basically consists of an electrode placed on the reproducing surface of a piezoelectric plate such as lithium tantalate, and an input/output transducer placed on one or two sides of the delay medium. Such ultrasonic solid state retarders are used in power 5-television receivers or video equipment, etc.

The main characteristic of this ultrasonic solid state retarder is the delay time (for example, L H = 63,556 μs, 2 H, l/2
H.

1/4 H) is determined by the time it takes for the ultrasound signal to propagate through the delay medium and reach the output transducer. In order to reduce the external dimensions of ultrasonic solid-state retarders, so-called multiple reflection type retarders are used in which the propagation path of an ultrasonic signal is reflected on each side of a delay medium.

Figure 1 shows an example of a conventionally known multi-reflection type ultrasonic solid state retarder. is a hexagon formed by cutting two corners between the long sides of a rectangle with a side ratio of 3:4 at an angle of 45''.The cut surface 2
．． 3. Install input/output converter 4.5. This input transducer 4 is constructed by arranging electrodes 41 and 42 on both sides of a piezoelectric plate 4° and connecting IJ-F wires 43 and 44, and output transducer 5.
Similarly, electrodes 51 and 52 are placed on the bidirectional surface of the piezoelectric plate 50, and the rays 53 and 54 are read directly. The input transducer 4 converts the electric signal supplied through the input-side beam-r wires 43 and 44 into an ultrasonic signal, and the ultrasonic signal follows a desired path inside the delay medium l as shown by the solid line and its arrow. and reaches the output transducer 5 where it is converted back into an electrical signal.

However, in this type of multi-reflection delay element,
In addition to the above-mentioned desired propagation path, the ultrasonic signal emitted from the input transducer 4 has a component 1 that spreads and propagates due to a diffraction phenomenon. This has the disadvantage that it is reflected from the side surface and directly reaches the output converter. Such an ultrasonic signal that passes through a path other than the desired propagation path is generally referred to as a "spurious signal" b). Since the generation of this spurious signal significantly reduces the fidelity of the output signal (delayed signal), it is necessary to suppress it in the ultrasonic solid state delay element. As shown in (0), the ultrasonic absorber 6 is added to the delay medium 1.
The absorber 6 is attached to an area other than the desired propagation path of the ultrasonic wave on the main surface of the ultrasonic wave. Even if an ultrasonic solid state retardator has some effect, it can still be a fundamental solution, especially if the number of reflection points is increased and the retardation medium is made smaller, the spurious suppression effect will be improved. It had the disadvantage of reducing

On the other hand, as a means of manufacturing this type of ultrasonic solid state retarder,
As will be described later, after installing the input/output converter on a block-like delay medium, the delay medium and the input/output converter are cut together to a predetermined thickness in order to mass-produce the same. The absorbent 6 is deposited on the main surface of the delay medium, and since this main surface corresponds to the cut surface in the manufacturing means, the absorbent adhesion process is carried out one delay element at a time after the cutting. Therefore, mass production means including the attachment of the absorbent 6 have not yet been established.

It is an object of the present invention to provide an ultrasonic solid state retarder which solves the above-mentioned drawbacks and problems and which facilitates the manufacturing means, namely, first, the propagation path of the spurious signal is basically The object of the present invention is to provide an ultrasonic solid retardator that is less likely to occur and, as a result, reduces the signal of the squirrel.Secondly, the object is to provide an ultrasonic solid retardator that can mass-produce the process of adhering an absorbent as a means for suppressing squirrel. Thirdly, the purpose is to provide an ultrasonic solid state retarder that facilitates the installation work of input/output transducers. An object of the present invention is to provide a sonic solid state retarder.

Hereinafter, the present invention will be explained in detail using drawings of embodiments.

The second WU shows an embodiment of the present invention, in which Figure (A) is a perspective view showing a block-like delay medium with an input/output converter installed, and Figure (0) shows details of the input/output converter. FIG. 1 is a perspective view of the present invention; FIG.

The block-shaped delay medium 100 is KiO-SrO-PbO
- Made of SiO2-based glass material, two side surfaces C and D whose cross-sectional shapes perpendicular to the longitudinal direction are parallel to each other, and the two side surfaces C
, D, and a surface opposite to side B, the right angle to approximately the midpoint of the opposing surfaces is an angle of 90@a, and the parallel Two sloped surfaces E and F formed at an angle of 45° with respect to the two side surfaces C and D, and a υ-shaped groove G formed toward the one side surface B9 perpendicular to the slopes of the sloped surfaces E and F.・In addition, when the area of the slopes E and F is made larger, the slopes E and F (including the groove G) among the opposing surfaces.

), 11
.

Therefore, when the areas of the slopes E and F are maximized, the surface A becomes the edge A'. In the case where this surface A has a reflection point of the ultrasonic propagation path as in this example, it does not necessarily have to be parallel to the one orthogonal side surface, but may be a curved surface or an inclined surface. It may be a surface or a surface of arbitrary shape.

Among the surfaces formed above, the inclined surfaces E and F on which the input/output transducer is installed and the side surface B which becomes the reflective surface of the ultrasonic propagation path;
For C and D, the surfaces are polished. Then, the plate-shaped input/output transducer 2001-300 (only the plate-shaped input transducer 200 is shown in FIG. The plate thickness (this example: 0.13 mm) is selected according to the frequency of the electric signal (this example: 8 MHz), and gold, silver, etc. , 203.The electrode 202 on the topsoil surface occupies approximately 80% of the area of the main surface, and the remaining area is covered with the electrode 203 on the back main surface, without contact with the electrode 202. In addition, in order to facilitate the glue-r wire connection with the electrode 202 on the topsoil surface, a solder flow prevention film 204 made of nickel-chromium alloy or the like is placed on the electrode 202 other than the glue-r wire connection area. Since the wiring and front wiring connection area does not substantially act as a transducer, no electrode 203 is disposed on the main mourning surface facing the area.

On the other hand, on the block-shaped delay medium 100, an ultrasonic absorber 400 such as a comb or epoxy resin is attached to the side of the delay medium other than the side surface having the reflection point of the ultrasonic propagation path.

Then, the above-mentioned plate-shaped input/output converter 200° 300 is installed on the inclined surfaces E and F of the block-shaped delay medium 100 via an adhesive. At that time, input/output converters 200, 30
It is performed by placing a rectangular parallelepiped weight on the main surface of 0. After the adhesive is fixed, the delay medium 100 and the input/output converter 200
, 300 and the ultrasonic absorber 400 are cut to a predetermined thickness (this example: 0.8 mm), and for each delay element, the input/output is connected to the delay medium 101 with the absorbent 401 attached to the side surface. The converters 205 and 305 are obtained, and the input/output converters 205 and 305 after cutting are connected to the -r lines 206, 207, and 3.
06. , 307 are connected to obtain an ultrasonic solid state retarder as shown in FIG. 2(d). 'Since the ultrasonic solid state delay element of this example has the above configuration, the propagation path of the ultrasonic signals of the input/output transducers 205 and 305 is on the side B,
Basically, the propagation path of the slip signal is formed with one reflection point at each of C and D, and is reflected directly from the opposite side surface at the time of launch and arrival as shown in Figure 1 (A). It has the advantage of not forming.

Also, if you want to further suppress spurious signals,
As shown in this example, the absorbent 400 is attached to the side surface of the block-shaped delay medium other than the side surface having the reflection point of the ultrasonic propagation path (propagates with a width comparable to the width of the transducer). For example, when disconnecting the delay medium and the input/output converter,
), an absorbent 401 can be installed on a predetermined side surface of the delay medium 101 as one delay element, and in this example, the absorbent 401 can be installed as one delay element.
It is installed on the sub-F of dB and can be sufficiently pressed simply by placing a weight on it, which has the advantage of obviating the need for the use of a special pressing machine as in the past.

3 to 6 show modified examples of the shape of the delay medium according to the present invention.
Then, by extending the side surface, the number of reflection points on the propagation path is reduced to surface A.
1 piece on side B, 2 pieces on side B, side C, D on side C,
By extending D together, the number of reflection points on the propagation path is 2 on plane A.
3 pieces on side B and 1 piece each on sides C and D.

Such modified examples of FIGS. 3 and 4 will be explained based on the previous embodiment, if the number of reflection points of the ultrasonic propagation path is
(M is a positive integer. However, in the case of the previous embodiment, M=O.) In the side view (d), extend the side surface B and change the number of reflection points to the surface A. There are zero pieces, one piece on side B, and two pieces each on sides C and D. Furthermore, the 6th r
By further extending the delay side B shown in lA, the number of reflection points is zero on side A, one on side B, and each (1+N) on sides C and D.
(N is a positive integer). In the above modification, the number of reflection points on the side surface in one direction is set to one, and the number of reflection points on the side surface perpendicular to the one direction can be appropriately increased, so the length dimension of the side surface in one direction can be reduced. can be converted into

In addition, although it was not initially anticipated, the ultrasonic solid retarder of the present invention was housed in a predetermined case section and subjected to a drop test, which is one of the reliability tests (10 natural drops from 1 m on cosiclete). As a result, while the conventional product was prone to damage to the input/output converter, damage to i did not occur in any of the Examples. This is because the input/output transducer according to the invention is placed within the recess of the delay medium.

[Brief explanation of drawings]

Figure 1 shows a conventional ultrasonic solid-state retarder, and Figure 1 (A) is a front view showing the propagation path of spurious signals in particular.
) is a front view particularly showing the ultrasonic absorber. FIG. 2 shows an ultrasonic solid state retarder which is an embodiment of the present invention. 2
1 (a) is a perspective view showing a plate-shaped input/output converter installed on a block-shaped delay medium, (0) is a perspective view showing the input/output converter in detail, and (8) is a perspective view showing the input/output converter in detail. A cross-sectional view of the input/output transducer, and the same figure (d) is a front view showing the ultrasonic solid state retarder of this example after manufacturing. 3, 4, 5, and 6 are front views showing ultrasonic solid state retarders according to other embodiments of the present invention. 101 , 102 , 103 , 104 , 105 ,
, , Delay medium 205... Input converter 305... Output converter Patent applicant Kishitki Co., Ltd. %1 Figure
Yamayo) Jiji

Claims (2)

[Claims] (1) Two side surfaces (C, D) parallel to each other, one side (B) perpendicular to the two parallel sides (C, D), and a peak on the surface opposite to the orthogonal one side (B). The angle is 90°,
and two inclined surfaces (E, F) formed at an angle of 45° with respect to the two parallel side surfaces (C, D). A transducer and an output transducer are installed, and the number of reflection points on each side of the propagation path of the ultrasonic wave emitted from the input transducer to the delay medium is
111- Surface (A) remaining other than the two inclined surfaces (E, F) among the opposing surfaces on the side where the surfaces (E, F) are formed
or on the edge (A") (M is a positive integer or zero.)
, (1-1-M) pieces on the one orthogonal side (B), and one piece each on the two parallel sides (C, D). (2) Two mutually parallel sides (C, D), one side CB) perpendicular to the two parallel sides CC, D), and an apex angle of 90 on the surface facing the orthogonal one side CB). ” angle,
and two inclined surfaces (E, F) formed at an angle of 45'' with respect to the two parallel side surfaces (C, D). A transducer and an output transducer are installed, and the number of reflection points on each side formed in the propagation path of the ultrasonic wave emitted from the input transducer to the delay medium forms the two inclined surfaces (E, F). Among the opposing surfaces on the side, +1 remaining other than the two inclined surfaces (E, F) (
N is a positive integer. ).