JPH0648772B2 - Method for manufacturing composite longitudinal vibration mechanical filter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention includes a longitudinal vibrating body (hereinafter, referred to as a longitudinal vibrating sound piece if necessary), a piezoelectric member, a coupling member, a support member, and the like, and has desired characteristics. The present invention relates to a method for manufacturing a composite longitudinal vibration mechanical filter in which longitudinal vibration sound pieces during formation are coupled by flexural vibration, and frequency fluctuation (variation) and deterioration of pass band characteristics are suitably reduced.

[Prior Art] In recent years, mechanical filters have been widely used in communication devices and the like as an intermediate existence in the characteristics of LC filters and crystal filters. Such a mechanical filter has good Q characteristics, selection characteristics, and temperature characteristics, and can be downsized.

An example of this type of composite longitudinal vibration mechanical filter is shown in FIG. In this example, the input-side vertical vibration sound piece 2 and the output-side vertical vibration sound piece 4 which are arranged on the same surface and made of a metal material or the like are included. Constant-elasticity connecting members 6 and 8 are connected to the input-side and output-side longitudinal vibration tones 2 and 4, and supporting members 10 and 12 are provided at the outer central portion so as to project. In this case, each of the above parts is produced by precision press working, laser welding, or the like. Further, a pair of input side piezoelectric ceramics 14a and 14b are polymerized and fixed to the input side vertical vibration sound piece 2 by soldering or the like.
The output side piezoelectric ceramics 16a and 16b are fixed to the. Next, the ends of the supporting members 10 and 12 are fixed to the upper center of the upright pieces 24a and 24b of the holding member 24 by laser welding or the like.

Further, between the input side piezoelectric ceramics 14a, 14b and the upright piece 24a, a power supply line 18 and a ground line 18 to which an input signal is supplied.
A lead wire that is connected to e and similarly derives an output signal
20 and the ground wire 20e are piezoelectric ceramics 16a and 16b on the output side.
And connected to the upright piece 24b.

With this configuration, the input-side and output-side longitudinal vibration tones 2 and 4 connected by the coupling members 6 and 8 are arranged substantially in the air, and the operation such as longitudinal vibration is not hindered. Has been formed. Then, the composite longitudinal vibration mechanical filter is housed in a casing or the like (not shown) and then mounted and used in an intermediate frequency amplifying unit of a communication device or the like.

In the composite longitudinal vibration mechanical filter configured as described above, the signal source Osc is provided between the feed line 18 and the ground line 18e.
A high-frequency signal S ₁ via a resistance R is applied to electrodes (not shown) attached to the input side piezoelectric ceramics 14a and 14b. And the input side longitudinal vibration sound piece 2 electrically grounded
An electric field corresponding to the high frequency signal is generated between the and. Due to this electric field, the input side piezoelectric ceramics 14a and 14b are
Electrostriction occurs in the directions indicated by Vm and Vn, and the input-side longitudinal vibrating sound piece 2 resonates at a frequency F ₁ having a half wavelength of a longitudinal wave having a length L ₁ . When the average propagation velocity of the longitudinal wave in the input side longitudinal vibration sound piece 2 is V, the frequency F ₁ is given by the following equation.

F ₁ = V / (2L ₁ ) ... (1) The longitudinal vibration at the frequency F ₁ is mechanically coupled to the output side longitudinal vibration sound piece 4 in the coupling members 6 and 8, and the output side vertical vibration sound piece 4 is long. It resonates with the longitudinal vibration of frequency F _{2 due to} the height L ₂ . This frequency F ₂ is F ₂ = V / (2L ₂ ) ... (2), where V is the average propagation velocity of the longitudinal wave of the output side longitudinal vibration sound piece 4 as in the equation (1). The output-side longitudinal vibration vibrating bar 4 of the longitudinal vibration by the output side piezoelectric ceramic 16a, voltage generated in 16b is derived as a high-frequency signal S ₂ formed in a predetermined steep frequency characteristic and lead-out wire 20 and the ground line 20e It

[Problems to be Solved by the Invention] However, in the above-described conventional composite vibration mechanical filter, the input-side and output-side longitudinal vibration sound pieces 2, 4 and the coupling members 6, 8 etc. are formed by precision press working or the like. Since it is often produced, the accuracy of the resonance frequency of each longitudinal vibrating sound piece that determines the characteristic and the accuracy of the coupling amount between each longitudinal vibrating sound piece are not sufficient. The inconvenience that the characteristics inside and outside the pass band are not formed to desired values is exposed, and its improvement has been a problem.

The present invention has been made in view of the above problems, and an object thereof is to determine a center frequency with high accuracy, improve characteristics inside and outside a pass band, and make the mass production uniform. An object of the present invention is to provide a method of manufacturing a composite longitudinal vibration mechanical filter that is promoted.

[Means for Solving the Problems] In order to solve the above problems, in a method for manufacturing a composite longitudinal vibration mechanical filter according to the present invention, a plurality of vibrating bodies including an input side and an output side on which piezoelectric members are superposed are provided. A composite longitudinal vibration mechanical filter in which a supporting member connected by a coupling member and abutting against an input-side and output-side vibrating body is attached to a holding member to form and derive a supplied high-frequency signal in a predetermined frequency band. A plurality of vibrating bodies including an input side and an output side of a high frequency signal, having a length corresponding to a center frequency of a pass band, and longitudinally vibrating in a region close to the pass band as a main vibrating body; A plurality of coupling members that are disposed between the ends of the plurality of vibrating bodies and that couple the vibrating bodies in flexural vibration,
The supporting member and the holding member are integrally manufactured from the one-plane member by a photolithography technique, and have an electrode plate to which a conductor is connected, the electrode plate having a length shorter than the length of the input side vibrator, and the electrode. The first piezoelectric member that causes longitudinal vibration in the input side vibrating body in response to the high frequency signal applied via the plate is superposed by sandwiching the input side vibrating body, and the length is shorter than the length of the output side vibrating body. A second piezoelectric member that has an electrode plate to which a conductor is connected, vertically vibrates by coupling through a coupling member, converts the longitudinal vibration into an electric signal, and outputs the electrical signal through the electrode plate. It is characterized by being produced by being polymerized with the body sandwiched.

[Operation] In the method of manufacturing a composite longitudinal vibration mechanical filter according to the present invention configured as described above, each longitudinal vibration body longitudinally vibrates in the vicinity of the pass band, and the coupling member formed between the longitudinal vibration bodies bends. It couples by vibration. In addition, each of the vertical vibrating members, the coupling member, and the like are manufactured as one element by etching or the like from one flat plate, so that the relative positions of these constituent elements (each of the vertical vibrating members and the coupling members) are constant. Become.

[Embodiment] Next, an embodiment of a method for manufacturing a composite longitudinal vibration mechanical filter according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a perspective view showing the steps of the manufacturing method, FIG. 2 is a perspective view showing the structure of a composite longitudinal vibration mechanical filter produced by adopting the steps of FIG. 1, and FIG. It is a perspective view which shows the other example of a structure.

First, the example shown in FIG. 2 will be described.

This example shows the input side vertical vibration sound piece 32 and the input side vertical vibration sound piece.
An output side longitudinal vibration sound piece 34 having the same shape as 32 is provided. The input-side and output-side longitudinal vibration tones 32 and 34 are arranged on the same surface, and are formed with thin coupling members 36 and 38 made of constant elastic materials. Further, the input-side and output-side longitudinal vibration tones 32 and 34 project from the central portion thereof and are supported by the support member 4
0 and 42 are provided.

Further, a pair of input side piezoelectric ceramics 44a and 44b are polymerized and fixed to the input side longitudinal vibration sound piece 32 by soldering or the like. Similarly, output side piezoelectric ceramics 46a and 46b are also superposed and fixed to the output side longitudinal vibration sound piece 34. Electrodes (not shown) such as metallization are previously formed on the surfaces of the input side piezoelectric ceramics 44a and 44b and the output side piezoelectric ceramics 46a and 46b. Then, the support member 40,
Each end of 42 is attached to the inner end surface of a rectangular outer frame member 50. In this case, the outer frame member 50 and the input-side and output-side longitudinal vibration sound pieces 32 and 34 are on the same plane. Further, a feed line 52 and a lead line 54 for feeding and leading a high frequency signal to and from the input-side and output-side piezoelectric ceramics 44a, 44b and 46a, 46b are wired, and also a ground line.
52e and 54e are wired.

In the above configuration, the input-side and output-side longitudinal vibration sound modules
Coupling members 36 and 38 are provided at the tips of 32 and 34, that is, at the portions where the displacement in the longitudinal vibration direction is large. Here, the vibration propagates (couples) by a transverse wave, so-called flexural vibration, whereby the spurious response is reduced and the pass band characteristic is improved.

The above-described manufacturing method using the photolithography technique will be described below in the order of steps.

In the first step (Fig. 1a), the input-side and output-side longitudinal vibration tones 32 and 34, the coupling members 36 and 38, the support member 40,
A photoresist layer 84 is applied on a metal flat plate 80 that includes the entire 42 and the outer frame member 50 on one surface and is designed to obtain desired longitudinal vibration characteristics.

In the second step (FIG. 1b), the input-side and output-side longitudinal vibration tones 32 and 34, the coupling members 36 and 38, the support member 40,
A mask pattern 86 including the same shapes as 42 and the outer frame member 50.
Through the light irradiation, for example, ultraviolet rays Lx are irradiated to perform an exposure process.

In the third step (FIG. 1 (c)), a developing treatment is performed by immersing in a solvent, and thereafter, the portions of the photoresist layers 87a, 87b, 87c of the portions that have been irradiated with light are removed.

In the fourth step (FIG. 1d), the photoresist layers 87a to 87a of the metal flat plate 80 removed in the third step are used.
The portion corresponding to 87c is removed by etching.

In this way, the input-side and output-side longitudinal vibration tones 32 and 34, the coupling members 36 and 38, the support members 40 and 42, and the outer frame member 50 are integrally formed.

Next, the input side and the output side in which the metallization of the gold material or the silver material is formed on the input side and output side longitudinal vibrating sound pieces 32 and 34 formed in the fourth step by using the vacuum deposition method or the sputtering method. Piezoelectric ceramics 44a, 44b
And 46a and 46b are polymerized and fixed by soldering.

Here, the input side vertical vibration sound piece 32 and the output side vertical vibration sound piece 34
Is set to a length corresponding to the center frequency of the pass band, the lengths of the input side piezoelectric ceramics 44a and 44b are set to be shorter than the length of the input side longitudinal vibration sound piece 32, and the output side piezoelectric ceramics 46a. The lengths of 46 and 46b are set to be equal to the lengths of the input side piezoelectric ceramics 44a and 44b and shorter than the length of the output side longitudinal vibration sound piece 34.

Furthermore, the input-side piezoelectric ceramics 44a and 44b are superposed on the front and back surfaces of the input-side vertical vibrating sound piece 32 so as to sandwich the input-side vertical vibrating sound piece 32.
46a and 46b are superposed from the front surface and the back surface of the output side vertical vibration sound piece 34 so as to sandwich the output side vertical vibration sound piece 34.

After this, the input side piezoelectric ceramics 44a and 44b and the outer frame member
The lead wire 54 and the ground wire 52e are connected to the output wire piezoelectric ceramics 46a and 46b and the outer frame member 50 with the lead wire 54 and the ground wire 54e by soldering.

Next, the operation of the above configuration will be described.

First, a pair of input side piezoelectric ceramic 44a, 44b and the input-side longitudinal vibration vibrating bar 32 a high-frequency signal from the signal source Osc via feed line 52 and the ground line 52e between the S _4, for example, the spar-heterodyne receiver, etc. 45 generated by the frequency converter of
An intermediate frequency signal of 5 KHz is provided. As a result, an electric field corresponding to the high frequency signal S ₄ is generated between the input side longitudinal vibration sound piece 32 and the input side piezoelectric ceramics 44a, 44b which are electrically grounded. This electric field causes electrostriction of the input side piezoelectric ceramics 44a and 44b in the directions indicated by arrows mi and mo in the figure, and the input side longitudinal vibration sound piece 32 has a frequency F ₄ having a length L ₄ as a half wavelength of a longitudinal wave. Resonates at.

In this case, the length L ₄ of the input side longitudinal vibration sound piece 32 is set to a length that satisfies the following expression (3) when the center frequency of the pass band is F _4, and is applied to the input side piezoelectric ceramics 44a and 44b. Electrostriction occurs in the input side piezoelectric ceramics 44a and 44b based on the generated high frequency signal, and the input side longitudinal vibration sound piece 32 is forcibly driven by this electrostriction to start longitudinal vibration. When the average propagation velocity of the longitudinal wave in the input side longitudinal vibration sound piece 32 is V, the frequency F ₄ is given by the following equation.

F ₄ = V / (2L ₄ ) ... (3) This longitudinal vibration is transmitted through the coupling members 36 and 38 to the output side longitudinal vibration sound piece.
The output side longitudinal vibration sound piece 34 responds to the vibration of the frequency F ₅ due to the length L ₅ , that is, resonates in the longitudinal vibration.

In this case, the length L ₅ of the output side longitudinal vibration sound piece 34 is set to a length that satisfies the following expression (4) when the center frequency of the pass band is F ₅ . Here, the frequency F ₄ = F ₅ is set. Therefore, the length of the input side vertical vibration sound piece 32 and the length of the output side vertical vibration sound piece 34 are set to be equal. If the average propagation velocity of the longitudinal wave of the output side longitudinal vibrating sound piece 34 is V, this frequency F ₅ is given by F ₅ = V / (2L ₅ ) ... (4). By the electrostriction of the longitudinal vibration of the output side longitudinal vibration sound piece 34, a voltage is generated in the electrodes (not shown) of the output side piezoelectric ceramics 46a and 46b, and a predetermined steep frequency characteristic is formed due to the transmission of the longitudinal vibration. That is, for example, an intermediate frequency signal of, for example, 455 KHz, which is formed into a narrow band frequency characteristic, is derived as an output signal S ₅ from the derivation line 54 and the ground line 54e.

Here, the input side vertical vibration sound piece 32 and the output side vertical vibration sound piece 34
The vibration of will be described.

Input side piezoelectric ceramic 44a, by longitudinal vibration is occurring on the input side longitudinal vibration vibrating bar 32 by electrostrictive of 44b, the input-side longitudinal vibration vibrating bar 32 starts longitudinal vibration frequency F _4. Here, the electrostriction caused by the input side piezoelectric ceramics 44a and 44b acts so as to cause the vibration of the input vertical vibration sound piece 32, and the main vibrating body is the input side vertical vibration sound piece 32 and the output side vertical vibration sound piece 34. is there. The input-side longitudinal vibration sound piece 32 causes not only longitudinal vibration but also bending vibration and torsional vibration, and also harmonic vibrations of each. Vibrations other than longitudinal vibration increase the spurious response. Since the resonance frequency of the plurality of vibrating bodies is close to the designed frequency because the filter is constructed by utilizing the resonance due to the longitudinal vibration, the vibration is maintained even in the vicinity of the longitudinal vibration resonance frequency. . When used as a filter, the frequencies in the vicinity of the longitudinal vibration resonance frequency are frequencies including not only the pass frequency band of the filter but also the stop band outside the pass band, and the vibration of the input side vertical vibration sound piece 32 is the coupling member 36. , 38 to be propagated to the output side longitudinal vibration sound piece 34. This propagation is performed based on the coupling coefficient of the coupling members 36 and 38. The pass band width is the width of the region where the input side vertical vibration sound piece 32 vertically vibrates and the engaging member.
It will be decided based on the coupling coefficient of 36 and 38.

Hereinafter, reduction of spurious response will be described.

The displacements of the input-side and output-side vertical vibration tones 32 and 34 in the vertical vibration direction are larger at the tips of the input-side and output-side vertical vibration tones 32 and 34. Further, the longitudinal vibration and the displacement in the vertical direction have large values in the central portions of the input-side and output-side longitudinal vibration sound pieces 32 and 34. Here, via the coupling members 36, 38,
The displacement in the vertical vibration direction caused by the vertical vibration of the input side vertical vibration sound piece 32 and the displacement in the vertical direction to the vertical vibration are transmitted (coupled) to the output side vertical vibration sound piece 34.

In this case, the displacement in the direction perpendicular to the longitudinal vibration is caused by the coupling members 36, 38.
Thus, not only is it coupled with the longitudinal vibration of the output side longitudinal vibration sound piece 34, but also vibrations due to other modes are also coupled. Therefore, the spurious response has a large value, which deteriorates the characteristics of the filter. Longitudinal vibration and vertical vibration are propagated as longitudinal waves mainly in the coupling members 36 and 38, and displacement in the longitudinal vibration direction is compared with longitudinal vibration and vertical displacement, and the longitudinal vibration in the output side is determined by the coupling members 36 and 38. Since it is coupled to the longitudinal vibration of the sound piece 34, the spurious response is small. Then, the vibration in the longitudinal vibration direction is generated by the coupling member 3
At 6 and 38, bending vibration occurs and propagates.

Therefore, the coupling member 3 is applied to a portion where the displacement in the longitudinal vibration direction is large, such as in the vicinity of the tips of the input-side and output-side longitudinal vibration tones 32 and 34.
6, 38 will be provided, the input side vertical vibration sound piece 32 and the input side vertical vibration sound piece 34 are connected by bending vibration of the coupling members 36, 38, and the input side vertical vibration sound piece 32, Output side longitudinal vibration sound piece 34, coupling members 36, 38, support members 40, 42, and outer frame member
The 50's are integrally configured on the same plane, their mutual positions are kept constant, and spurious response is reduced. The reason for this is that, in addition to the vertical vibration, other vibration modes occur in the input side vertical vibration sound piece 32 and the output side vertical vibration sound piece 34 to increase the spurious response, but as described above, Since the input-side and output-side longitudinal vibration tones 32 and 34, the coupling members 36 and 38, the support members 40 and 42, and the outer frame member 50 are integrally configured, there is no change in the positional relationship between the respective constituent members. , The input side and output side longitudinal vibrating sound elements 32 and 34 which are the main vibrating body
There is no change in the mutual positional relationship between the connecting members 36 and 38,
As a result, the longitudinal vibration does not change into unnecessary mode vibration, and the spurious response is reduced.

Further, the input-side and output-side vibrating sound pieces 32 and 34 are the main vibrating bodies, and the input-side and output-side vibrating sound pieces 32 and 34 are
Are coupled by the coupling members 36 and 38, the input side longitudinal vibration sound piece 32 of the input side piezoelectric ceramics 44a, 44b.
The vertical vibration frequency of the input side vertical vibration sound piece 32 is changed unless the ends of the input side piezoelectric ceramics 44a and 44b come out of the end of the input side vertical vibration sound piece 32 even if the upper position changes during superposition. The same applies to the output side longitudinal vibration sound piece 34, and even if the positions of the input side and output side piezoelectric ceramics are slightly shifted, the spurious response does not increase, so the spurious response is substantially reduced. It is. This improves the pass band characteristic.

The deterioration of the pass band characteristic is mainly due to the variation in the coupling amount due to the coupling members 36 and 38. However, since the coupling members 36 and 38 couple the input-side vertical vibration sound piece 32 and the output-side vertical vibration sound piece 34 by bending vibration, the pass band characteristic is improved.

Further, the displacement of the input-side vertical vibration sound piece 32 in the vertical vibration direction is larger at the tip portion thereof and is a function of the position in the vertical vibration direction. Therefore, in order to reduce the variation between the elements, which are the longitudinal vibration sound pieces, as the desired characteristics, it is necessary to make the coupling amount of the output side vertical vibration sound piece 34 to the input side vertical vibration sound piece 32 constant. is there. Here, the input side longitudinal vibration sound piece 32 of the coupling members 36 and 38 is
It is necessary to keep the relative position with respect to as constant as possible, and the photolithography of the input side vertical vibration sound piece 32, the output side vertical vibration sound piece 34, the coupling members 36 and 38, the support members 40 and 42, and the outer frame member 50. By using the technique, by making an etching method from one flat plate, those constituent elements (the input and output side longitudinal vibration sound pieces 32 and 34, the coupling members 36 and 38, the support members 40 and 42 and the outside members) are formed. The relative position of the frame member 50) can be kept constant.

Furthermore, the amount of coupling between the input-side vertical vibration sound piece 32 and the output-side vertical vibration sound piece 34 is determined by the attachment positions of the connection members 36, 38 and the shapes such as the width and length of the connection members 36, 38. However, by the photolithography technique, the relative position is kept constant and the pass band characteristic is not deteriorated or varied as described above.

Next, FIG. 3 shows another embodiment which is composed of five longitudinal vibrating tones and has an improved attenuation outside the pass band.

In this example, a plurality of longitudinal vibrating sound pieces 72, 74, 76 are provided between input-side and output-side longitudinal vibrating sound pieces 70, 78, and further, coupling members 82a, 82b and 84a, 84b and 86a, 86b and 88a are provided. , 88
In b, the longitudinal vibration sound pieces 70 to 78 are connected.

Support members 90 and 92 are provided so as to project from the central portions of the input-side and output-side vertical vibration sound pieces 70 and 78, and the end portions thereof are fixed to the outer frame member 110.

Further, a pair of input side piezoelectric ceramics 99a and 99b and output side piezoelectric ceramics 101a and 101b are polymer-fixed to the input side and output side longitudinal vibration sound pieces 70 and 78. Reference numerals 122, 122e and 124, 124e are a power supply line, a ground line, a lead line, and a ground line, respectively.

The operation of such a configuration is basically the same as that of the above-mentioned embodiment, and the duplicated description thereof will be omitted.

As described above, when the multistage vertical vibration sound pieces 70 to 78 are arranged, the variation between the vertical vibration sound pieces 70 to 78 is reduced, and in particular, the effect of improving the pass band characteristic is obtained. large.

[Advantages of the Invention] As described above, according to the method of manufacturing the composite longitudinal vibration mechanical filter of the present invention, in the composite longitudinal vibration mechanical filter that forms and supplies the supplied high frequency signal in a predetermined frequency band, the high frequency signal A plurality of vibrating bodies including the input side and the output side, which vibrate longitudinally in a region close to the pass band, and an electrode plate to which conductors are respectively superposed on the input side vibrating body and the output side vibrating body. A piezoelectric member, a plurality of coupling members that are disposed between the ends of the plurality of vibrating bodies, and that couple in flexural vibration, and a support formed by projecting from the input side vibrating body and the output side vibrating body. A member and a holding member for holding a plurality of vibrating bodies including the input side and the output side to which the supporting member is attached, and the plurality of vibrating bodies and the holding member are integrally formed as a single flat plate member. It is characterized by being created by the trizography technique.

As a result, the center frequency is determined with high accuracy, variation in the center frequency is suppressed, the pass band characteristic is improved, and individual characteristics during mass production are made constant,
It has the effect of improving quality.

Since the vibrating body, the coupling member, the support member, and the outer frame member are integrally formed, and the positional relationship between the vibrating body and the coupling member is always constant, there is no change in the mutual position and the spurious response is reduced. It Further, since the length of the piezoelectric element is set shorter than the length of the vibrating body, the vibrating body is the vibrating body, and it is easy to set the position of the piezoelectric element with respect to the vibrating body. As a result, even if the position of the piezoelectric member is slightly displaced, the frequency of vibration does not change.

Further, since the vibrating body is the main vibrating body and is easier and more accurate to machine than the piezoelectric member, there is an effect that the frequency of vibration can be accurately set.

In addition, since the piezoelectric element is superposed so as to sandwich the vibrating body, the vibrating body can easily generate vibration, and there is an effect that a large level of output can be taken out. Further, bending vibration is unlikely to occur in the input side vibrating body. Even if flexural vibration occurs in the output-side vibrating body, the electric output is canceled and the electric output based on the flexural vibration is not transmitted.

Furthermore, the longitudinal vibration of the vibrating body has a sine wave-shaped displacement distribution depending on the position in the longitudinal vibrating direction with the center of the vibrating body as the symmetry point. Then, the stress applied to the vibrating body is distributed in the shape of a cosine wave, and it is effective that the piezoelectric member for causing vibration by applying the stress is superposed on the upper and lower surfaces of the central portion of the vibrating body. Further, even if the overlapping position of the piezoelectric member fluctuates from the central portion in the length direction of the vibrating body with a small amount of sinusoidal displacement, the displacement distribution of longitudinal vibration does not change significantly. As a result, there is also an effect that the displacement of the longitudinal vibration coupled by the coupling member is less affected by the variation in the overlapping position of the piezoelectric member.

[Brief description of drawings]

FIG. 1 is a perspective view showing a process of a method for manufacturing a composite longitudinal vibration mechanical filter according to the present invention, and FIG. 2 is a perspective view showing a structure of a composite longitudinal vibration mechanical filter produced by using the process of FIG. FIG. 3 is a perspective view showing another structural example of a composite longitudinal vibration mechanical filter produced by using the process of FIG. 1, and FIG. 4 is a structural example of a composite longitudinal vibration mechanical filter according to a conventional technique. It is a perspective view shown. 32 ... Input side vertical vibration sound piece, 34 ... Output side vertical vibration sound piece 36, 38 ... Coupling member, 40, 42 ... Support member 44a, 44b ... Input side piezoelectric ceramics 46a, 46b ... Output side piezoelectric ceramics 50 ... Outer frame Member 80 Metal flat plate 84 Photoresist layer 86 Mask pattern Lx UV

 ─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP 59-161113 (JP, A) JP 54-51498 (JP, A) JP 61-6915 (JP, A) JP 61- 121512 (JP, A) Actually opened Sho 60-82837 (JP, U) Japanese Patent Sho 44-24961 (JP, B1)

Claims (1)

[Claims] 1. A plurality of vibrating bodies including an input side and an output side, in which piezoelectric members are superposed, are connected by a coupling member, and a supporting member which is abutted against the vibrating body on the input side and the output side is attached to a holding member. In the manufacturing method of the composite longitudinal vibration mechanical filter that forms and derives the supplied high-frequency signal in a predetermined frequency band, the length corresponding to the center frequency of the pass band including the input side and the output side of the high-frequency signal is set. A plurality of vibrating bodies that vertically vibrate in a region close to the pass band as a main vibrating body, and a plurality of couplings that are arranged between end portions of the plurality of vibrating bodies and that couple the vibrating bodies in bending vibration. Members,
The supporting member and the holding member are integrally manufactured from the one-plane member by a photolithography technique, and have an electrode plate to which a conductor is connected, the electrode plate having a length shorter than the length of the input side vibrator, and the electrode. The first piezoelectric member that causes longitudinal vibration in the input side vibrating body in response to the high frequency signal applied via the plate is superposed by sandwiching the input side vibrating body, and the length is shorter than the length of the output side vibrating body. A second piezoelectric member that has an electrode plate to which a conductor is connected, vertically vibrates by coupling through a coupling member, converts the longitudinal vibration into an electrical signal, and outputs the electrical signal through the electrode plate. A method for producing a composite longitudinal vibration mechanical filter, which is produced by sandwiching a body and polymerizing.