DE2220487A1 - PIEZOELECTRIC COMPOUND TRANSMITTER - Google Patents

Description

Dr.-Ihg. Wilhelm Reiche! DipL-ing. Wolfgnng example.

6 Frankfurt a. M. I.

Park street 13.

7039

TOYO TSUSHINKI KABUSHIKI KAISHA, Kanagawa-Ken, Japan

Piezoelectric composite transducer

3533SS = SSSSSSSSSSaSaSaS = SS = SS = SSS =

The invention relates to a composite piezoelectric oscillator, which consists of at least two piezoelectric single oscillators, so-called thickness oscillators, in which the piezoelectric effect is coupled with shear, twisting or stretching forces. The invention also provides a method for Manufacture of this composite piezoelectric transducer.

Recent developments have created a need for piezoelectric transducers with very high oscillation frequencies. For this purpose, a special piezoelectric vibrator of thin thickness and low strength or strength is required. For this reason, warping of the piezoelectric vibrator occurs as a result of warping of the holder during assembly or use of the piezoelectric vibrator and as a result of deformation of the holding members due to external stress, whereby the oscillation frequency of the piezoelectric vibrator experiences changes. In addition, the assembly of the piezoelectric composite oscillator is relatively difficult and expensive.

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The invention is based on the object of creating a composite piezoelectric oscillator which has the above disadvantages does not own, but can be produced easily and cheaply and is fes * and is stable in its design and perfectly maintains its vibrational state over a long period of time.

Another object of the invention is to provide methods which can greatly facilitate the assembly of the composite piezoelectric vibrator simple, cheap and effective way and enable a composite transducer with the required excellent oscillation properties as well as methods for tuning and measuring the various properties of the composite transducer.

The invention relates to a piezoelectric composite oscillator, which is primarily characterized by the fact that it has at least two piezoelectric single oscillators, of which each is provided with the necessary electrodes on its surfaces, a base and at least two through the base having holders carried isolated from one another, the holders serving as feed lines to the transducers or electrodes and the transducers only with circumferential points at the ends of the holder, parallel to one another and apart from one another at the circumferential points are attached separately, electrically conductive, so that a desired circuit diagram results.

Further features and advantages of the invention emerge from the following description together with the claims and the appended Drawings in which the invention is explained and illustrated using exemplary embodiments. In the drawings demonstrate:

Pig. 1a is a partially sectioned front view of an embodiment of the invention which embodies a filter circuit diagram;

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Pig. 1b shows a section along the line Ib-Ib in Pig. 1a; Pig. 1c shows a side view of the embodiment in Pig. 1a;

Pig. 2a ■ '

and FIG. 2b views of two single oscillators as shown in Pig. are united;

Pig. 2c shows a view of a common piezoelectric single oscillator for forming a composite oscillator;

Pig. 3 shows an equivalent circuit diagram to the embodiment according to Pig. 1; . .

Pig. 4 shows the circuit diagram of a filter with four piezoelectric composite oscillators according to the embodiment Pig. 1;

Pig. 5a, 5b, 6a, 6b, 8a, 8b front and side views of the Holders of three other embodiments of the invention;

Pig. 6c is a perspective view of the in Pig. 6a and 6b shown holder;

Pig. 7 shows a modified embodiment in side view of the keeper after Pig. 6;

Pig, 9a a view of a single transducer for use in Scope of the invention; "

Pig. 9b shows a front view of a composite oscillator which consists of three individual oscillators according to FIG. 9a;

Pig. 9c is an equivalent circuit diagram of the Pig composite oscillator. 9b;

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Pig. "10a, 10b, 10c, 10d Views of four individual oscillators for use in the context of the invention;

Pig. 1Oe a front view of a composite transducer, which consists of the in Pig. 10a-d consists of single oscillators shown;

Pig. 1Of an equivalent circuit diagram of the Pig composite oscillator. 1Oe;

Pig. 11a and 11b views of single oscillators with a split Electrode;

Pig, 11c a front view of a composite swinger from the Individual swinging according to Pig. 11a ~ bj

Pig. 1Id an equivalent circuit diagram of the composite transducer Pig. 11c;

Pig. 12a, 12b, 12c, 12d corresponding to FIGS. 11a-d Positions of a modified composite oscillator of the

Invention; . * -

Pig. 13a a view of another embodiment of the invention _; \ Pig. Figure 13b is a front view of the nac & Pig embodiment. 1Yes ^ /

Pig. 13c and 13d show a holder in front and side views, respectively for execution according to Pig. 13a - b {

Pig. Ha and Hb in plan and front view an andörefa Holder according to the invention;

Pig. Hc a front view of the holder according to Pig. Ha-b, in which two single oscillators are held and fastened

Pig «15 in a front view a modified form of execution of the holder and the attachment according to Pig. H;

P.ig. I6b in front view another embodiment of the invention! '

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Pig. 16a shows a side view of the embodiment according to FIG. 16b;

Pig. 16c is an equivalent circuit diagram of the implementation of the Pig. I6a-b;

Pig. 18a and 18b in front and side views, respectively, a piezo. composite electric oscillator of the invention, whose individual whistle-blowers are united and coordinated according to a new procedure;

Pig. 17a, 17b, 17c, 17d views of the four individual oscillators, which the composite vision wirger according to Pig. 18 form;

Pig. 19a and 19b show the installation of a first single oscillator for a composite oscillator in front and side views, respectively with two single oscillators; ■ '

Pig. 19c and 19d show the cultivation of a front and side view, respectively second single oscillator to the Pig arrangement. 19a-b; ;

Pig; 20a, 20b, 20c> 20d views of four individual oscillators;

Pig. 21a and 21b in front and side views, respectively, a composite. Schwinger from the pig's individual swingers. 20;

Pig. 22a and 22b a first in plan and front view, respectively Modification of the execution according to Pig. 21;

Pig. 23a and 23b in front and side views, respectively, of a second Modification of the execution according to Pig. 21;

Pig. 24 is an equivalent circuit diagram of the embodiment of FIG Pig. 21;

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Pig. 25a and 25b show a modification in plan and front view, respectively of the composite oscillator according to Pig. 22;

Pig. 26 is an equivalent circuit diagram of a crystal filter in which the circuit diagram according to Pig. 24 is used;

Pig. 27a, 27b, 27c, 27d are views of four individual oscillators for a composite oscillator according to the invention;

Pig. 28 an equivalent circuit diagram for a composite transducer from the individual transducers of Pig. 27;

Pig. 29a, 29b, 29c, 29d Views of four other individual

vibrate for the union to form a composite vibrator according to the invention; ^:

Pig. 30a and 30b are views of two further individual oscillators for assembly into an improved composite transducer according to the invention;

Pig. 32a and 32b show a composite oscillator in a plan view and a front view, respectively from the pig's individual swingers. 30a-b;

Pig. 31 an equivalent circuit diagram of the composite oscillator after Pig. 32;

Pig. 33 shows a further improved composite oscillator in a front view according to the invention;

Pig. 34a, 34b, 34c, 34d Views of four individual oscillators

for assembly to form a composite oscillator according to the invention;

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35a and 35b in front and side views, respectively, of a composite transducer from the individual transducers from Pig. 34, in which identical or equivalent parts are denoted by the same numbers and letters.

According to Pig. 1, AI-cut crystal oscillators 1 and 4 are provided on their front and rear sides with silver electrodes 2, 3 and 5 "» 6, which are applied by vapor spraying. Each of these oscillators is hereinafter referred to as a piezoelectric single oscillator, MO ._. BinajelÄC_hwi As can be seen from Pig. 1, .nger_J .; _:. and ._ .. 4 are combined to form a composite piezoelectric transducer with the equivalent circuit diagram shown in Pig. 3. The circuit diagram of Pig. 3 can serve as a circuit element, for example a crystal filter ( Center frequency 10.7 MHz and bandwidth -— - 7 kHz), as described in

Pig. 4 is shown, in which each of the circuit elements framed by dotted lines corresponds to the circuit diagram of the Pig. 3 corresponds.

In Pig. 1, a base 13 consists of a lid 15 and a glass gasket 14, and lead wires 10, 11, 12 are separated passed through the base 13 and held. The lead wires 10, 11, 12 carry elastic retaining plates 7 or 8 or made of stainless steel (hereinafter referred to as holder) provided with slots or cutouts 7s, 8s, 9a of width W (Pig. 1c) are provided, which is slightly greater than the sum of the thicknesses of the individual oscillators 1 and 4.

In order to keep the individual oscillators 1 and 4, they are attached to the circumference or places in the slots 7s, 8s, 9s added, so that they are aligned parallel to each other and in between there is a gap G which can be 0.1 mm and which is suitable not to allow contact in their central areas (The thickness oscillation is in the central area of the

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Single oscillator concentrated), apart from their peripheral parts, and then aie are made by applying electrically conductive adhesive or binding agent compositions 7d, 8d, 9d to these Circumferential points fastened in the holders.

With the above-described union of the individual oscillators 1 and 4 is to be noted beforehand, the shape and the execution locations of the front and rear electrodes as in FIGS. 1 and 2a, 2b shown so that the circuit diagram of Fig. 3 is obtained.

So far, only one piezoelectric single oscillator 30, as shown in FIG. 2c, has been used on the front and rear provided with electrodes 30a, 30b, held in two slots, such as slots 7s and 9s in Fig. 1, and by electrical conductive adhesive to make a crystal vibrator without the holder 8 and the lead wire 11 shown in FIG Fig. 1a to be taken into account. Instead, it was customary to use a plurality of individual oscillators, as in connection with FIG. 2c described above, to be connected in terms of circuitry.

In contrast, if the composite transducer of the invention according to Fig. 1, Fig. 2a and 2b and Fig. 3 is used, the work steps of applying and curing the binding agent for a plurality of individual transducers are carried out together and the work for the fine tuning of the oscillation frequency significantly reduced by applying a metal such as silver by means of vacuum evaporation. In general, in fine-tuning the oscillation frequency, the time required for a vacuum to be formed in a vacuum container is longest, and the time required for taking the single vibrators into and out of the vacuum housing and for vapor deposition is shorter than the aforementioned Time.

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In the Pall of the invention, the individual oscillators are in parallel Alignment set on top of each other while maintaining a gap that allows them to swing freely between them, so that the Vapor deposition for both individual oscillators simultaneously from both sides, as indicated by the directional arrows in Fig. 1b, can take place while the oscillators are individually excited to vibrate thickly and their frequencies are monitored. ”In the case of the embodiment According to Fig. 1, the time required for all manufacturing steps of the composite oscillator is reduced by half.

Without being shown, the socket 13 ^m i 't a metal cap provided may be covering the vibrator and is soldered hermetically or welded on. In this case, the metal cap is filled with nitrogen, thereby obtaining a final product. In this embodiment, the Time required for attaching the metal cap and filling the cap with nitrogen half as much as with the usual method.

Even if single oscillators for the composite oscillator of the invention with different linear thermal expansion coefficients along the X-axis and the Z-axis (Fig. 2a and 2b), as in the case of a crystal vibrator, used and on three Interactions between the individual oscillators as a result of temperature changes can be negligible can be made by uniting the individual oscillators in such a way that that axes of the same thermal expansion coefficient are aligned with one another. Then there is no problem in terms of temperature oscillation.

The slot in the holder for receiving the individual oscillators can be modified by adding each holder 16 littleatens receives two slots 18 and 18a, each of which only receives a single oscillator.

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- ίο -

Furthermore, according to FIGS. 8a and 8b, the holder 24 can be designed as a spiral coil or helix 25 at its upper end and on its lower end 26 to be soldered to the lead wire 27, wherein the coil 25 the single transducer 1 between two adjacent Picks up and holds turns. In addition, the individual oscillator 4 is shown in FIG. 8 with a circumferential point on the edge of the holder 24 or attached to the end face of the helix 25 and connected by binding agents.

In all cases it is important to only hold the single oscillator by its circumference. According to FIG. 6, this can also be done in such a way that that the individual oscillators 1 and 4 by means of an electrically conductive binder mass 21 at the side edges Pa and Qa des Holder 19 (Fig. 6b) are attached. According to FIG. 6c, a step or shoulder 20 can be provided on the side edge Pa to ensure the attachment and electrical contact of the single oscillator. Furthermore, the can from a spring plate Existing holder 19 can be replaced by a spring wire, with a special attachment being made on the side edge without providing for paragraph 20. In this case, the spring wire can be united with the lead wire.

Fig. 7 relates to an embodiment in which the slot mount is combined with edge fastening in order to attach the individual oscillators 1, 4, 4a to a holder 22. In Fig. 7 the soldering is indicated by a mass 23.

Practical mountings are illustrated in FIGS. 9-12. According to FIG. 9, three of the individual oscillators according to FIG. 9a are held in two holders according to FIG. 9b, so that a switching element according to FIG. 9c results.

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According to FIG. 10, four individual oscillators according to FIGS. 10 a - d in held five holders according to FIG. 10e, so that a switching element according to FIG. 10f results.

According to FIGS. 11 and 12, there are two individual oscillators Type with split electrode according to FIGS. 11a-b or 12a-b held in four holders or six holders, whereby switching elements according to Fig. 11d and 12d result, the execution with slit electrode is suitable for filters, transducers and discriminators. The switching element according to FIG. 1Id corresponds to a Filter and the switching element according to Fig. 12d corresponds to a filter discriminator, at the point da for the conductive .Verbschluss the element is suitable and does not have a holder.

The embodiment according to FIG. 1 can be modified in such a way that the individual oscillators are held in such a way that they are perpendicular to the longitudinal direction of the holder, as shown in FIGS. 13a-d, in which the same parts as in FIG are denoted by the same numbers and letters * In Fig. 13, the holders 7, 8, 9 are provided at their ends with elongated transverse slots 8 .. and 82, the width of which is slightly greater than the thickness of the individual oscillators, and two individual oscillators 1 and are received and held at circumferential locations in the slots of the holders 1, 8, 9, wherein they are fastened at these locations by electrically conductive bonding agents 7d, 8d, 9d.

The holders 7, 8, 9 can be modified according to FIGS. 14 and 15. will. In Fig. 14, the holder 8 is provided at its end with only one slot or incision 8, and the individual oscillators 1 and 4 are fixed at peripheral locations by electrically conductive bonding agent 8d in the slot 8, so that they are in their central areas are separated by a gap G. In contrast, in FIG. 15 the holder 8 is shown in its supporting part or at its end as a coil or helix as in the case of FIG.

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formed, and the individual oscillators 1 and 4 are between adjacent Turns of the helix held and fastened by a binder mass 8d. In this pail there can be another single chair 4a can be attached to the outside by means of a conductive binding agent mass 8d4.

If five holders 7,8,9,28,29 with four slots each corresponding to the slots of the holder in Fig. 15c, d are used, can have four single transducers 1, 4, 4a, 4b like those in Pig. 10a - 4L are effectively combined to form a composite oscillator, as shown in FIGS. 16a and 16b, whereby a switching element with the circuit diagram of the Pig. 16c is obtained, furthermore, the Holder according to Pig. 13c and Ud for the embodiment in Pig. 9;. ' can be used with the same effects. The holders of the embodiments in Pig. 11 and 12 by the holder. in Pig. 13c and 13d can be replaced with the same results *

Within the scope of the invention, each of the individual oscillators described above can be used in a shape other than circular, such as rectangular or elliptical, with the same results be formed.

The manufacture of the composite oscillator like that in FIG. 5 is described in detail in connection with Figs. 18a and 18b * in which each of the holders 16a to 16e attached to lead wires 16 ^ 1 to I6d1 are attached, which are held in a base 13 are provided with four slots 18a to 18d and four single oscillators 1, 4, 4a, 4b according to FIG. 17 held in the slots and on the holder by means of electrically conductive bonding agents 17a to 17d are attached.

When a precision adjustment of the frequency is to be carried out »all parts are placed in one housing; the Kin * elaohwinger 1st in % _; i «Soklit · 18 * in dtr position gea. fig. I7b uew. held and dta

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Holders 16a and 16e by binding agent 17a and the like. Then, silver bowl is sprayed from an evaporation point P through a window W of a mask VL onto the back of the individual oscillator 1 \. During this Sprührorganga the individual vibrator 1 is set in oscillation by electrical excitation via its electrodes 2 and 5 and lead wires I6a1 and 16q1 and the deviation (decrease) in the oscillation frequency is monitored or regulated.

Next; the neighboring double oscillator 4 is in the Slot 8b inserted and on the holders 1.6a to I6e Binder 17b, etc. attached. This attachment is special care to ensure that the orthogonal projections of the backs of the individual transducers 1 and 4 in the are essentially placed concentrically on top of each other. After the attachment of the single oscillator 4, the painful vote is on the back of the aa single oscillator in the same way * as carried out at the single winger t. Ebenao will be the following Single oscillators 4a and 4b are used one after the other and fastened and then fine-tuned the frequency.

As already mentioned, each of the single oscillators is very thin and the gap between adjacent individual oscillators can be chosen to be smaller than the thickness of each individual oscillator, so that the width of the overall arrangement of all individual oscillators is relatively small, although this width is shown exaggeratedly large for clarity in Mg, 18b iat. As a result, as long as the orthogonal projections of the rear sides of the individual oscillators are kept in a concentric position, it is practically not necessary to change the position of the composite oscillator relative to the position of the Maake M and the point P, although the frequency must be fine-tuned one after the other: on geaetzt'-in single sewing yarn is made, with the back caeitedea from 4UJtimmenden Uohwingera ulch gradually ier Maike M

-H-

approaching. This fact is a very advantageous condition for mass production of the composite vibrator described above.

For example, a common device for torture voting the frequency by application by means of vacuum evaporation, which is intended for only one single oscillator as it is, can be used to fine tune the frequency of a composite transducer of the invention. Recently there is a vapor deposition apparatus with a rotating tower or turret head, and here the individual oscillators, which are finely tuned in terms of their frequency, are used inserted, paused, fine-tuned and taken out, making the time to establish a vacuum for each transducer is shortened by performing a vacuum operation in common ^; carried out for all individual transducers, thereby simplifying and automating the fine-tuning. In the case of the invention the above-mentioned device can be used for a single oscillator is suitable to be used for the production of the composite oscillator according to the invention.

The same advantage as mentioned above can be found in the work of inserting each individual vibrator into the slot (s) Incision of the holder and the application of the binding agent to the point with which the single transducer is attached to its holder is intended to be applied, but the benefit obtained with the vapor deposition apparatus is most notable.

Furthermore, the process steps are no longer just repetitions a simple step, as it is suitable for the division of a single oscillator, ao that the method according to the Invention can be easily carried out.

In the production of a piezoelectric configuration, according to the invention, it is essential to use the following elements: lj hwin _t ', i>v; io, one above the other, that the orthogonal pro; iktio ·, η

IQl ν. j M

BATH ORIGINAL

- ■ 15 -

their backs are held in a substantially concentric position. The reason for this is as follows.

In general, the circle diameter of the back and the Thickness of each individual oscillator has a close relationship with inductance the equivalent circuit of the same, - this relationship being an important point in the manufacture of a transducer, in particular a vibrator for an electric filter.

On the other hand, it is in the case of fine-tuning the oscillation frequency by applying to the back of the transducer, an indispensable condition for achieving an excellent Oscillator, the back suitable for fine-tuning the frequency exactly coincides with the provisionally plated To make back or to bring these backs in concentric superimposed and adjacent layers. When the circle centers of the rear sides do not match, the inductance of the composite oscillator becomes noticeably different from the intended value differ and parasitic oscillation is amplified, making it difficult to manufacture a filter of desired properties. .

The successful mass production of composite transducers according to the invention without loss of quality is made possible by consideration the aforementioned connections made possible.

The invention further provides that the base and the lead wires according to FIGS. 19a and 19b are embodied in that the base is designed as a crystal plate 31 and the conductors 31a to 31e are attached to the plate by vapor deposition or printing, with a single oscillator 1 with divided electrodes 1a and 1b is held at circumferential locations by electrically conductive binder masses 32a to 32e, which are attached to the conductors, as clearly shown in FIG. 19b, whereupon

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the fine-tuning of the frequency of the single ohwinger 1 is carried out in the manner already described.

Next, as shown in FIGS. 19c and 19d, another single oscillator 4 with split electrodes 1a1 and 1b1 is attached at points on its circumference by electrically conductive binding agents 33a to 33b, which are attached to the binding agents 32a to 32e, whereupon the frequency of the single oscillator is fine-tuned 4 is carried out. In this embodiment of the invention, the binding agents 32a to 32e and 33a to 33e serve as special holders. As the embodiment of FIG. 19 shows, the holders are not necessarily common for all individual oscillators, but the holders of one individual oscillator can be attached to the holders of the other individual oscillator.

In this case, when the transducer is cut from an AI Crystal oscillator is formed, the base also from a Αϊ-cut crystal plate or a crystal plate with a linear expansion coefficient that is the same that of the Αϊ-cut crystal plate is made and these ropes are placed one on top of the other so that they are axially aligned with the same linear expansion coefficient, whereby a Device is obtained, the different thermal expansion of which can be neglected and so interfering influences on the oscillator be avoided .. This method is mainly applicable to a transducer for a high frequency and with a thin one Thickness dimension.

A piezoelectric composite oscillator according to the invention can be embodied as shown in FIGS. 20 and 21 by four individual 3 oscillators 1, 4, 4a, 4b naoh Fig. 20 at circumferential points duroh five holders made of stainless spring parts 35 are held and on the holders by means of electrically conductive binding agents

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34a1 to 34e1 are attached.

The electrically conductive binder masses 34 ^a to 34e at individual vibrator 1 in Pig. 20a are applied and cured in advance. The other individual oscillators 4 »4a, 4b are also provided with conductive binding agents corresponding to binding agents 34a to 34e. When the individual oscillators 1, 4, 4a, 4b are combined, the binding agents 34a to 34e are connected to the holders 35 by conductive binding agents 34a1 to 34e1. The binder masses 34a to 34e help to ensure the gap between the adjacent individual oscillators of this embodiment and the embodiment according to FIG. 29 to be described later. .

The individual oscillators 1, 4, 4a, 4b are provided with front and rear electrodes 2, 3 and 5, 6 and 2a, 3a and 5a, 6a, respectively are applied by silver evaporation. The holders 35 are connected to the corresponding lead wires 36, which through a base 13 are passed through and attached to this. If the individual oscillators 1, 4, 4a, 4b in side one above the other must be held set positions, the holders 35 are modified, as shown in Fig. 22a and 22b is shown.

The holder 35 of the embodiment according to FIG. 21 can also be modified according to FIG. 23, where each holder 35 is made of stainless steel There is wire and is U-shaped at one end.

The exemplary embodiments of FIGS. 21, 22, 23 can be represented by the equivalent circuit diagram according to FIG. 24, which can be used to set up a crystal filter circuit (for example for an average frequency of 10.7 MHz and a bandwidth of ί 7 kHz) , in which each dashed framed component of the circuit diagram of the ? ig. 24 corresponds.

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If a composite piezoelectric transducer is desired, whose circuit corresponds to the scheme framed by the dash-dotted line 6, it is only necessary to connect the electrodes 3 of the single oscillator 1 in FIG. 20a on the binding agent 34b and the electrodes 6a of the single oscillator 4a in Pig. 2Od to align with the binder masses 34d.

Each holder 35 of the Pig embodiment. 22 can be converted into a spiral or spiral holder. In this case each of the individual oscillators 1, 4, 4a, 4b is attached between adjacent turns of the helical holder, which with corresponding lead wires 36 are connected, which of a Base 13 are carried, as for the embodiment in FIG Pig. 25 is shown.

If four single transducers 1, 4, 4a, 4b with split electrodes are used, like those in Pig. 27 shown, each of which is provided with separate front electrodes 38a and 38b and with a rear electrode 39, then da3 can be equivalent Circuit diagram according to Pig. 28 can be obtained.

The composite transducer specified above can be further improved according to the invention by using the individual transducers according to Pig. 29 are used, in which a single oscillator 1, to which front and rear electrodes 2 and 3 are attached, to his Perimeter is provided with weight lines 37a to 37e, which consist of an epoxy binder and printed on the surface and are fully hardened, while the other individual oscillators 4, 4a, 4b are designed in the same way as the oscillator 1. The binder of weight lines 37a to 37ο can be from electrical conductive nature aein or not.

The width of the weight lines is, for example, 0.2 to 0.4 mm, and if a circular crystal plate about 0.16 mm thick and 6 - 8 mm in diameter is used for the fiinzQluchwinger,

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each of the weight lines has a length of 1 - 1.5 mm and a thickness of 10-50 micrometers and 'is printed so that an edge section 38 of 0.2-0.3 mm width remains free on the circumference of the individual oscillator.

If a single swinger, like in Pig. 29 is shown over its electrodes is excited, its oscillation is known to be greatest in a central circular zone of the electrodes and the The area near this central zone becomes the vibration zone. This vibration weakens towards the outer hand after one Exponential function decreases and becomes in the outer area, the one Has a diameter of 1.5 to 3 times the central circular zone, irrelevant. Hence, when there is ice in the mentioned area are arranged, which carries out almost no vibration, no great effect on the vibration in the central Have zone of the single oscillator. The weight line. practices the function of a weight that causes acoustic losses and almost all parts of the oscillation? which in 'this extent = area of the single oscillator remain, absorbed.

When assembling the piezoelectric Einselachwinger 1, 4, 4a, 4b according to FIG. 29, these are combined as they are or, if necessary, in connection with the embodiment of the Pig. 18 already mentioned voting subject. The union of the individual oscillators can deviate from this in the same way as in connection with the old embodiment of the Pig. 21, 23, 22 or 25 described _s can be achieved *

Furthermore, when combining the individual oscillators of Fig. if necessary, a measurement of the oscillation frequency and the crystal impedance or a selection test can be carried out by applying a voltage to the connection points to which the. Weight lines are in contact if they are made of electrically conductive material, or on the execution parts of the

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Electrodes.

The four piezoelectric single oscillators 1, 4, 4a, 4b according to Fig. 27 can be compared with the methods described in Pig. 27 may be provided, whereby a circuit diagram according to Pig. 28 with the In Relation with Pig. 29 described additional advantages can be obtained.

In the embodiment of the invention according to Pig. 30, 31 »32, the crystal plates 39 and 40 are provided with filters P, S and Q, R having divided electrodes and a plurality of weight lines 40 which are able to absorb acoustic energy. The crystal plates 39 and 40 are first subjected to the tuning of frequency and bandwidth as well as the measurement and selection and then combined according to FIGS. 32a and 32b. In this case, the individual transducers forming crystal plates 39 and 40 are attached to holders 411, 41E and 41, 0 and fixed by means of electrically conductive binder slurry 42, such that the crystal plates a gap are old in parallel over each other without contact with each other, except at their circumference parts, wherein the holders are connected to lead wires I, E and 0, which are passed through a base 13 and held in this. The crystal plates are attached to the periphery in an electrically conductive manner by means of a binding agent mass 43. ·

An equivalent circuit diagram for the filter formed by the composite transducer of FIG. 32 is in Pig. 31 reproduced in to which the filters P, Q, R and S are continuously connected and lie between the input terminal I and the output terminal 0. The crystal plates 39 and 40 can be attached to holders 411, 41E and 41 0 which are inserted into holes 45 (Fig. 30) previously formed in the plates, such as is shown in Fig. 33, in which electrically conductive fastening parts are omitted. In the Pail of Fig. 33, converters,

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inductances or the like. Members 44 in the space under the over- " placed on each other crystal plates 39 and 40 be attached, and another crystal or ceramic plate 45 »on one lumped circuit is provided that contains amplifiers, limiters, discriminators, can be done in the same way as that Crystal plates 39 and 40 be attached.

Corresponds to the structure of the piezoelectric composite oscillator after Pig. 33 can be a synthetic circuit that has a Intermediate frequency filter, an amplifier, a limiter and a frequency discriminator contains, as a unitary compact Formed. To be produced.

An important task of the additional weight lines, such as the Weight lines 37a through 37e in Pig. 29 »is to prevent» that the oscillation propagates to the holding parts of the individual oscillators, as already explained above. Training the weight lines can be done according to different methods, such as screen printing, brush application, vacuum spraying and the like, and the weight lines can be formed from any material such as epoxy resin and other organic substances. Furthermore, the arrangement of the weight lines is not limited to that in Pig. 29 limited distribution, but can according to Pig. 34 can be modified in which the weight lines on each the individual oscillators are attached in such a way that the oscillation zone is subdivided. The four individual swingers of the Pig. 34a to 34d are according to Pig. 35a and 35b combined, creating an equivalent Circuit diagram is obtained that corresponds to the circuit diagram in Pig. 1Of is equivalent to.

With those in Pig. 29 to 35 illustrated embodiments the weight lines are provided to counter the single piezoelectric swinger against the port planting of the oscillation Circumference of the transducer. protection. But can the same we-

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kung can be achieved by the places of the weight lines partially be diluted. For the purpose of forming the partially thinner areas in a transducer, there are various methods, such as Spark erosion, chemical etching, supersonic grinding and the like.

The above-explained application of weight lines and thinning can be used in combination in order to suppress the propagation to the hand portions of each of the piezoelectric single owls.

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Claims (1)

Claims Piezoelectric Verbundachwinger, because ά u τ ο h characterized that at least two piezoelectric single wake that. are provided with the required electrodes on their surfaces, are only held parallel to each other at points of their circumference by at least two holders and apart from one another except for the circumferential parts, the holders with the individual wings or their electrodes are permanently connected to the Urafangastellen and the Holders insulated from one another on or in a common base, the supply lines o & ev eieren extensions forming, attached are incL 2. comprise composite transducer according to claim 1, characterized in which the holder ₉ at its ends openings for the Jkufnahme the Einsselschwlnger and these to the Äufaali: ii are © @ st Ilesa by electrically conductive means to the retainers, respectively. 3. Composite transducer according to claim 1, characterized in that the holders have at least awei longitudinal slots or incisions at their ends and the holders with circumferential points in the slots or incisions are fixed by electrically conductive means » 4. composite oscillator according to claim 1 _e, characterized in that the holder rest at their ends with edges on circumferential points of the individual oscillators and these are connected at the contact points by electrically conductive means with the holders feat. 309808/1135 5 * composite transducer according to claim 1 »thereby -» marked that the cold at their '■. Ends with a bobbin or helical part jJt ' are and the individual aohwinger with tiafangestellen "wipe ^ ₄ adjacent turns of the coil or helix held and * " ^Λ attached by electrically conductive means «lad. 'V 6. composite oscillator according to claim 1, d a d ur o h marked that the edge and at least a slit or unity at the end of each colder the Attachment and fastening of the Binieleohwinger is used. 7. Composite transducer according to claim 1, characterized in that;,; marked that dit around the middle Λ. · ! Ceil of the pedestal arranged around holders on their booths. '■, ^; have at least one cross section or unit . -f '' \ ■ j and the single oscillators with circumferential locations in the pile strands. , j or incisions parallel to each other and off at the;, '- ^:'. ' ^! Peripheral parts held separately from one another and fastened ; I *:. sina. · ■. · -. · .. ■■■■■■ '....: .-. 8. composite oscillator according to claim 7, since you raw -: ^ ^Λ -'Ji j marked that each holder of fine '^. ._, End designed as a coil or helix let and each oscillator is held and fixed between adjacent turns of the coil or helix. 9. Process for the production of a composite ohms according to one of the preceding claims, characterized in that characterized in that a first single oscillator after attachment in holders on peripheral parts attack and serve as leads by making an application on its rear surface of a vote 309808/1135 is subjected to its oscillation frequency, which is directly or indirectly a second individual oscillator above the first .Single transducer is attached to the brackets in such a way that that the orthogonal projections of the rear surfaces of the two individual oscillators are essentially one another are concentric, and then the second single oscillator in the same way as the first single oscillator is subjected to a tuning of its vibration frequency by application on its rear surface, and that these steps of mounting and tuning in connection with the other individual transducers that the should include finished composite transducers, to be repeated. 10. composite oscillator according to claim 1, characterized in that each holder consists of There is spring plate, the end of which has such a width that the individual oscillators are placed one on top of the other laterally and is able to grasp and hold fixed by means of electrically conductive binding agent mass. 11. composite oscillator according to claim 1, characterized it is marked that each holder is made of spiral wire with a U-shaped end of such width, that the individual oscillators are placed one on top of the other and by means of an electrically conductive binding agent able to grasp and hold fast. 12. composite oscillator according to claim 1, characterized characterized in that each holder consists of spring steel sheet which holds the individual oscillators serving end has such a length that it the individual oscillators in the longitudinal direction one above the other set and attached by means of electrically conductive binding agent to grasp and hold. 309808/1135 13. 'composite oscillator according to claim 1, characterized characterized in that each holder is made of spiral wire and between adjacent turns at its end, the individual oscillators are captured and held. H. 'composite oscillator according to claim 1, characterized in that each single oscillator in its area surrounding the main oscillation zone is provided with additional lines that create an acoustic To cause loss or a thorough damping of the oscillation and thereby a propagation of the Able to prevent vibration bia to the holders. 15 · composite oscillator according to claim H, characterized characterized in that the additional parts by applied to the surface of the individual oscillators, weight lines surrounding the oscillation zone of the same are formed. ' 16. Composite oscillator according to claim 14, characterized in that the additional Parts are formed by partial dilutions in the area of the individual oscillators. 17. Method for producing a composite oscillator according to Claim 14, characterized in that the one acoustic loss or one thorough damping of the vibration causing additional parts on each of at least two piezoelectric Single ear swingers In an area surrounding the main oscillation zone, the various Adjustments or adjustments such as frequency adjustment and measurement are carried out that several individual oscillators prepared in the above manner 3098QJ / 1135 Set on top of each other in parallel alignment and separated from each other except at the circumferential points and then the single swingers at the ümfangstellen be combined in an electrically conductive manner to form the composite transducer, ν 18. Composite transducer according to claim 1, characterized in that »the base is designed as a crystal plate» the lead wires are attached to the plate, a Binzelschwiftger is attached to the lead wires at peripheral locations by means of electrically conductive binding agents and a further single oscillator is attached to peripheral locations by means of electrically conductive binding agents the binder compositions of the first Einselechwingers is parallel to and secured at a distance therefrom, while, optionally, other single element in "4p same manner are carried ■■ - ■■ · '■ -'...";"--.-■." ·. - .; ^f -, "- ..- ■ '■ 19 «Composite transducer according to Anepiuch 18 # d a d u f c h g e k e η η show η β t »that the single oscillator (s) and the base is axially aligned with one another and have the same linear expansion coefficients. ReNeu / Pi. 309808/1135