JPWO2020202351A1 - Ultrasonic transducer and its manufacturing method - Google Patents

Abstract

The ultrasonic transducer according to the present invention surrounds an elastic plate capable of vibrating in the plate thickness direction, a plurality of piezoelectric elements fixed in parallel to the first surface of the elastic plate, and a plurality of piezoelectric elements in a plan view. A plurality of tubular portions and a flexible wiring plate are provided, and the elastic plate includes a plurality of vibration regions in which the plurality of piezoelectric elements are mounted, a plurality of low-rigidity regions surrounding the plurality of vibration regions, and a plurality of low-rigidity regions. The boundary region includes a plurality of restraint regions surrounding each of the low-rigidity regions of the above, and a boundary region for partitioning one restraint region and an outer region located radially outward from the one restraint region. It has a slit portion that divides one restraint region and the outer region, and a bridge portion that mechanically connects the one restraint region to the outer region. The flexible wiring board has an insulating layer fixed to the upper surface of the tubular portion and a wiring conductor provided on the upper surface of the insulating layer, and the wiring conductor is an upper electrode layer of the plurality of piezoelectric elements. Each has a plurality of tip regions that are electrically connected to each other.

Description

The present invention relates to an ultrasonic transducer in which a plurality of piezoelectric elements are arranged in parallel and can be suitably used as a phased array sensor, and a method for manufacturing the same.

An ultrasonic transducer in which a plurality of vibrating bodies including a piezoelectric element and a diaphragm are arranged in parallel is suitably used as a phased array sensor for detecting the shape of an object or detecting the presence or absence of an object over a wide range. It is possible, but in this case, the ultrasonic transducer is required to have the following items.

That is, in order to suppress the occurrence of the grating lobe phenomenon between a plurality of vibrating bodies, it is necessary to set the arrangement pitch of the plurality of vibrating bodies to 1/2 or less of the wavelength λ of the ultrasonic waves radiated by the vibrating bodies. There is.

On the other hand, in order to detect an object several meters away, it is necessary to set the frequency of the ultrasonic waves emitted by the vibrating body used in the ultrasonic transducer to a low frequency of about 40 kHz.

Since the wavelength λ of the ultrasonic wave having a frequency of 40 kHz is 8.6 mm, in order to suppress the occurrence of the grating lobe phenomenon while setting the frequency of the ultrasonic wave radiated by the vibrating body to 40 kHz, the arrangement pitch of a plurality of vibrating bodies is set. It is necessary to make it 8.6 mm / 2 = 4.3 mm or less.

However, at present, the diameter of the vibrating body capable of emitting ultrasonic waves of 40 kHz is about 10 mm, and therefore, it is impossible to satisfy the above-mentioned requirements by using the current vibrating body.

In this regard, a configuration (hereinafter referred to as a first conventional configuration) in which a waveguide (acoustic tube) is combined with a normal vibrating body that emits ultrasonic waves of 40 kHz has been proposed.

In the first conventional configuration, one end side opening of the waveguide is connected to each of a plurality of vibrating bodies arranged in parallel, and the vibrating body radiates the arrangement pitch of the other end side opening of the waveguide. It is configured so that it can be reduced to 1/2 or less of the wavelength of ultrasonic waves.

However, in the first conventional configuration, there is a problem that the overall size of the sensor including the waveguide becomes large.
There is also a problem that the reflection of ultrasonic waves generated in the waveguide adversely affects the radiation profile of ultrasonic waves.

As a configuration different from the first conventional configuration, an ultrasonic transducer having a plurality of vibrating bodies manufactured by using MEMS (Micro Electro Mechanical Systems) technology (hereinafter referred to as a second conventional configuration) has been proposed (hereinafter referred to as a second conventional configuration). For example, see Patent Documents 1 and 2 below).

In the second conventional configuration, the size of the diaphragm vibrated by the piezoelectric element can be 400 to 800 μm, and a plurality of vibrating bodies can be arranged at an arrangement pitch of λ / 2 or less.

However, in the second conventional configuration, the size of the diaphragm becomes too small, and it becomes difficult to generate low-frequency ultrasonic waves of about 40 kHz, which are necessary for detecting an object several meters away.
In addition, there is a problem that the manufacturing cost rises as the manufacturing process becomes complicated.

JP-A-2010-164331 Japanese Unexamined Patent Publication No. 2013-046086

The present invention has been made in view of such a prior art, and is an ultrasonic transducer having a plurality of piezoelectric elements arranged in parallel, and an arrangement of a plurality of vibrating bodies each formed by the plurality of piezoelectric elements. While narrowing the pitch, it is possible to prevent vibration propagation between the plurality of vibrating bodies as much as possible, and further, it is effective that the voltage supply path for the plurality of piezoelectric elements affects the vibration characteristics of the plurality of vibrating bodies. The first object is to provide an ultrasonic transducer that can be prevented or reduced.
A second object of the present invention is to provide a manufacturing method capable of efficiently manufacturing the ultrasonic transducer.

In order to achieve the first object, the first aspect of the present invention is an elastic plate having a first surface and a second surface facing one side and the other side in the plate thickness direction, respectively, and vibrating in the plate thickness direction. A plurality of piezoelectric elements fixed in parallel to the first surface of the elastic plate, a sealing member having a plurality of tubular portions surrounding each of the plurality of piezoelectric elements in a plan view, and a flexible wiring plate. The elastic plate is provided with a plurality of vibration regions in which the plurality of piezoelectric elements are mounted, a plurality of low-rigidity regions surrounding the plurality of vibration regions in a plan view, and the plurality of low-rigidity regions in a plan view. The low-rigidity region includes a plurality of restraint regions surrounding each region and a boundary region for partitioning one restraint region and an outer region located radially outward from the one restraint region, and the low-rigidity region is a region of the region. The rigidity is lower than that of the vibration region located inward in the radial direction and the restraint region located outside in the radial direction of the region, and the boundary region is a slit that divides one restraint region and the outer region. It has a portion and a bridge portion that mechanically connects one restraint region to the outer region, and the plurality of tubular portions are arranged so as to surround the plurality of low-rigidity regions in a plan view. The flexible wiring plate has an insulating layer fixed to the upper surface of the tubular portion and a wiring conductor provided on the upper surface of the insulating layer, and the wiring conductor is an upper surface electrode layer of the plurality of piezoelectric elements. Provided is an ultrasonic transducer having a plurality of tip regions electrically connected to each other.

According to the ultrasonic transducer according to the first aspect of the present invention, vibration is propagated between the plurality of vibrating bodies through the elastic plate by the slit portion in the boundary region while narrowing the arrangement pitch of the plurality of vibrating regions. This can be prevented or reduced as much as possible.
Therefore, low-frequency ultrasonic waves can be effectively radiated while effectively preventing or reducing mutual interference between the plurality of piezoelectric elements.

Further, in the ultrasonic transducer, the vibration region is flexibly supported via the low rigidity region, and a low resonance frequency can be realized even if the area of the vibration region is reduced, and the vibration region can be realized. Sound pressure can be increased.

Further, in the ultrasonic transducer, the flexible wiring board is not directly fixed to the elastic plate but is fixed to the upper surface of the tubular portion, so that the flexible wiring board is fixed to the plurality of vibrating bodies. It is possible to effectively prevent or reduce the influence on the vibration characteristics of the above.

In one form, the wiring conductor may have a main body region located on the insulating layer and a plurality of tip regions extending outward from the main body region so as to extend outward from the insulating layer.
In this case, the tip region has a connection terminal for a piezoelectric element that is electrically connected by a conductive adhesive or solder in a state of being polymerized on the upper surface electrode layer of the corresponding piezoelectric element in a plan view.

The piezoelectric element is configured such that the upper surface of the upper surface electrode layer is located at the first height with respect to the first surface of the elastic plate, and the upper surface of the tubular portion is based on the first surface of the elastic plate. When the tip region is configured to be located at a second height higher than the first height, the tip region has a second height with respect to the first surface of the elastic plate for the connection terminal for the piezoelectric element. It is configured to be located at a third height below the first height and above the first height.

In the various configurations, the tubular portion is arranged so that the base end surface straddles the slit portion, and the sealing member is, in addition to the tubular portion, the slit portion from the base end surface of the tubular portion. It may have a filling portion extending inward of the.

According to such a configuration, the posture of the restraint region can be stabilized, and the reliability of the ultrasonic transducer can be improved.

The sealing member may further have a closing portion that closes each of the free end sides of the plurality of tubular portions.

According to such a configuration, sound wave leakage from the side of the first surface of the elastic plate can be effectively suppressed.

Preferably, the tubular portion and the filling portion are integrally formed of the first polymer material, the closed portion is formed of the second polymer material, and the first polymer material is based on the state before curing. Therefore, the viscosity is lower than that of the second polymer material.

According to such a configuration, the filling portion can be stably filled in the slit portion.

In the configuration having the closed portion, the ultrasonic transducer may have a rigid reinforcing plate fixed to the outer surface of the closed portion.

Preferably, a protective member having an opening that opens the vibration region to the outside is fixed to the second surface of the elastic plate.

According to such a configuration, contact from the outside with the elastic plate can be effectively prevented, and damage to the elastic plate can be effectively prevented.

More preferably, a rigid protective plate provided with a through hole at a position corresponding to the opening is fixed to the outer surface of the protective member.

According to such a configuration, damage to the surface of the protective member can be effectively prevented, and vibration of the surface of the protective member can be suppressed.

A rigid protective plate provided on the outer surface of the protective member instead of the protective plate and the reinforcing plate, which is fixed to the outer surface of the protective member and has a through hole at a position corresponding to the opening of the protective member. A rigid protective plate having a central portion provided with a portion and an extending portion extending outward in the plate surface direction from the central portion, and a rigid reinforcing plate provided on the outer surface of the closed portion, wherein the closed portion is provided. A rigid reinforcing plate having a central portion fixed to the outer surface of the surface and an extending portion extending outward in the plate surface direction from the central portion can be provided.
In this case, the extending portion of the reinforcing plate and the extending portion of the protective plate are connected via a spacer.

According to such a configuration, the deformation of the elastic plate due to an external force can be suppressed more effectively, and damage to the elastic plate and the piezoelectric element can be effectively prevented or reduced.

A protective container may be provided in place of the protective plate.
The protective container extends along the outer surface of the protective member and surrounds an end wall portion provided with a through hole at a position corresponding to the opening of the protective member and the outer periphery of the protective member and the elastic plate. It is assumed that it has a peripheral wall portion extending from the end wall portion.
In this case, the reinforcing plate is connected to the peripheral wall portion so as to close the free end opening of the peripheral wall portion of the protective container while covering the outer surface of the closed portion.

With such a configuration, the deformation of the elastic plate due to an external force can be suppressed more effectively, and damage to the elastic plate and the piezoelectric element can be effectively prevented or reduced.

In the various configurations, preferably, a sound absorbing material made of foamable resin is provided in the accommodation space of the piezoelectric element surrounded by the tubular portion in a plan view so as to surround the piezoelectric element.

According to such a configuration, sound wave leakage from the side of the first surface of the elastic plate can be effectively suppressed.

In the various configurations, preferably, the ultrasonic transducer is a mass member fixed to the first surface of the restraint region so as to open the first surfaces of the vibration region, the low rigidity region, and the boundary region. Can be equipped.
In this case, the tubular portion is arranged so that the base end surface straddles the slit portion, and the insulating layer of the flexible wiring board is fixed to the upper surface of the mass member in addition to the upper surface of the tubular portion. ..

According to such a configuration, the vibration of the restraint region can be suppressed, the cross stroke between the plurality of vibration regions can be reduced, and the vibration amplitude of the vibration region can be increased to increase the sound pressure of the generated sound wave. ..

In the configuration having the mass member, preferably, a sound absorbing material made of foamable resin is provided so as to surround the piezoelectric element in the accommodation space of the piezoelectric element surrounded by the mass member in a plan view.

In order to achieve the first object, the second aspect of the present invention is an elastic plate having a first surface and a second surface facing one side and the other side in the plate thickness direction, respectively, and vibrating in the plate thickness direction. A plurality of piezoelectric elements fixed in parallel to the first surface of the elastic plate, a mass member fixed to the first surface of the elastic plate, and a flexible wiring plate. A plurality of vibration regions to which a plurality of piezoelectric elements are mounted, a plurality of low-rigidity regions surrounding the plurality of vibration regions in a plan view, and a plurality of restraint regions surrounding the plurality of low-rigidity regions in a plan view. , The low-rigidity region includes the boundary region that separates one restraint region and an outer region located radially outward from the one restraint region, and the low-rigidity region is the vibration located radially inward of the region. The rigidity is lower than that of the region and the restraint region located on the outer side in the radial direction of the region, and the boundary region is outside the one restraint region and the slit portion that divides the outer region and the one restraint region. The mass member has a bridge portion mechanically connected to the square region, and the mass member opens the first surface of the vibration region, the low rigidity region, and the boundary region, and the low rigidity region in a plan view. The flexible wiring plate is fixed to the first surface of the restraint region so as to surround the body, and has an insulating layer fixed to the upper surface of the mass member and a wiring conductor provided on the upper surface of the insulating layer. The wiring conductor provides an ultrasonic transducer having a plurality of tip regions electrically connected to the upper surface electrode layers of the plurality of piezoelectric elements.

According to the ultrasonic transducer according to the second aspect of the present invention, vibration is propagated through the elastic plate between the plurality of vibrating bodies by the slit portion in the boundary region while narrowing the arrangement pitch of the plurality of vibrating regions. This can be prevented or reduced as much as possible.
Therefore, low-frequency ultrasonic waves can be effectively radiated while effectively preventing or reducing mutual interference between the plurality of piezoelectric elements.

Further, in the ultrasonic transducer, the vibration region is flexibly supported via the low rigidity region, and a low resonance frequency can be realized even if the area of the vibration region is reduced, and the vibration region can be realized. Sound pressure can be increased.

Further, in the ultrasonic transducer, the flexible wiring board is not directly fixed to the elastic plate but is fixed to the upper surface of the mass member, so that the flexible wiring board is attached to the plurality of vibrating bodies. It is possible to effectively prevent or reduce the influence on the vibration characteristics.

Further, the mass member can suppress the vibration of the restraint region, reduce the cross stroke between the plurality of vibration regions, and increase the vibration amplitude of the vibration region to increase the sound pressure of the generated sound wave.

In the second aspect, preferably, a sound absorbing material made of a foamable resin is provided so as to surround the piezoelectric element in the accommodation space of the piezoelectric element surrounded by the mass member in a plan view.

According to such a configuration, sound wave leakage from the side of the first surface of the elastic plate can be effectively suppressed.

In the second aspect, in the configuration in which the mass member has a plurality of restraint region mass members fixed to the first surface of the plurality of restraint regions so as to surround the plurality of low rigidity regions in a plan view. Preferably, the ultrasonic transducer is further free of a plurality of tubular portions and the plurality of tubular portions provided in the boundary region so as to surround the plurality of restraint region mass members in a plan view. A sealing member including a closing portion that closes each end side and a rigid reinforcing plate fixed to the outer surface of the closing portion can be provided.

According to such a configuration, contact from the outside with the elastic plate can be effectively prevented, and damage to the elastic plate can be effectively prevented.

Preferably, a protective member having an opening that opens the vibration region to the outside is fixed to the second surface of the elastic plate.

According to such a configuration, contact from the outside with the elastic plate can be effectively prevented, and damage to the elastic plate can be effectively prevented.

More preferably, a rigid protective plate provided with a through hole at a position corresponding to the opening is fixed to the outer surface of the protective member.

According to such a configuration, damage to the surface of the protective member can be effectively prevented, and vibration of the surface of the protective member can be suppressed.

Also in the second aspect, a rigid protective plate provided on the outer surface of the protective member instead of the protective plate and the reinforcing plate, which is fixed to the outer surface of the protective member and opens the protective member. A rigid protective plate having a central portion provided with a through hole at a position corresponding to the above and an extending portion extending outward in the plate surface direction from the central portion, and a rigid reinforcing plate provided on the outer surface of the closed portion. A rigid reinforcing plate having a central portion fixed to the outer surface of the closed portion and an extending portion extending outward in the plate surface direction from the central portion can be provided.
In this case, the extending portion of the reinforcing plate and the extending portion of the protective plate are connected via a spacer.

According to such a configuration, the deformation of the elastic plate due to an external force can be suppressed more effectively, and damage to the elastic plate and the piezoelectric element can be effectively prevented or reduced.

Also in the second aspect, a protective container can be provided in place of the protective plate.
The protective container extends along the outer surface of the protective member and surrounds an end wall portion provided with a through hole at a position corresponding to the opening of the protective member and the outer periphery of the protective member and the elastic plate. It is assumed that it has a peripheral wall portion extending from the end wall portion.
In this case, the reinforcing plate is connected to the peripheral wall portion so as to close the free end opening of the peripheral wall portion of the protective container while covering the outer surface of the closed portion.

With such a configuration, the deformation of the elastic plate due to an external force can be suppressed more effectively, and damage to the elastic plate and the piezoelectric element can be effectively prevented or reduced.

In the various configurations of the first and second aspects, for example, the low stiffness region may have a groove that opens on the first surface of the elastic plate.

Instead, the low-rigidity region may include an opening that divides the vibration region and the restraint region, and a connecting portion that connects the vibration region and the restraint region.
In this case, the openings and the connecting portions are alternately provided along the outer peripheral edge of the vibration region.

Instead, the low-rigidity region may be a concave thin-walled region in which the first surface is closer to the second surface than the first surface of the vibration region and the restraint region.

In this case, the piezoelectric element includes a central portion that overlaps with the vibration region in a plan view, and an extending portion that extends radially outward from the central portion and ends in the low rigidity region in a plan view. It is said that.
The lower surface electrode layer in the central portion is fixed to the first surface of the vibration region by an insulating adhesive, and the lower surface electrode layer in the extending portion is electrically connected to the first surface of the low rigidity region by the conductive adhesive. Connected mechanically and mechanically.

In the configuration in which the low-rigidity region is the concave thin-walled region, preferably, the bottom surface of the thin-walled region is a raised portion lower than the first surface of the vibration region, and is co-located with the inner surface of the thin-walled region. A ridge is provided that works to form an adhesive retention region.
The conductive adhesive that electrically and mechanically connects the lower surface electrode layer in the extending portion and the first surface of the low rigidity region is provided in the adhesive retention region.

In the various configurations of the first and second aspects, for example, the plurality of restraint regions are formed by m (m is an integer of 1 or more) constrained regions arranged along the direction of the first plate surface of the elastic plate. The constrained region group to be formed has n rows (n is an integer of 1 or more) in the second plate surface direction orthogonal to the first plate surface direction, and has m × n constrained regions that appear by being provided. It is supposed to be.

In this case, preferably, the slit portions are located on both sides of the piezoelectric element mounted on the vibration region in the restraint region in the direction of the second plate surface, and extend along the direction of the first plate surface. 1st plate surface direction slit and a pair of second plate surface direction slits located on both sides of the one piezoelectric element in the first plate surface direction and extending along the second plate surface direction. The pair of first plate surface direction slits is longer than the first plate surface direction length of the one piezoelectric element, and the pair of second plate surface direction slits is longer than the second plate surface direction length of the pair of piezoelectric elements. It is long, and is configured such that four points defined between the ends of the first plate surface direction slit and the second plate surface direction slit adjacent to each other in the circumferential direction form the bridge portion.

More preferably, a single common slit is provided between the adjacent constrained regions, and the single common slit defines the outer peripheral edges of both adjacent constrained regions.

In order to achieve the second object, the present invention has a first surface and a second surface facing one side and the other side in the plate thickness direction, respectively, and can vibrate in the plate thickness direction. A plurality of piezoelectric elements fixed in parallel to the first surface of the plate, a sealing member having a plurality of tubular portions surrounding each of the plurality of piezoelectric elements in a plan view, and a flexible wiring plate are provided. The elastic plate surrounds a plurality of vibration regions in which the plurality of piezoelectric elements are mounted, a plurality of low-rigidity regions surrounding the plurality of vibration regions in a plan view, and a plurality of low-rigidity regions in a plan view. The low-rigidity region includes a plurality of restraint regions and a boundary region that partitions one restraint region and an outer region located radially outward from the one restraint region, and the low-rigidity region is radially inward of the region. The rigidity is lower than that of the vibration region located in and the restraint region located outside the radial direction of the region, and the boundary region includes a slit portion that divides one restraint region and the outer region. The flexible wiring plate has an insulating layer fixed to the upper surface of the tubular portion and an insulating layer fixed to the upper surface of the insulating layer. The wiring conductor is a method for manufacturing an ultrasonic transducer having a plurality of tip regions electrically connected to the upper surface electrode layers of the plurality of piezoelectric elements. An elastic plate forming step of etching a conductive elastic plate forming body to form the elastic plate, and conductively adhering the lower surface electrode layers of the plurality of piezoelectric elements to the first surfaces of the plurality of vibration regions. A piezoelectric element mounting step of bonding with an agent, a tubular portion installation step of installing the plurality of tubular portions so as to surround each of the plurality of low-rigidity regions in a plan view, and a wiring conductor provided on the upper surface of the insulating layer. A flexible wiring plate formed of a flexible wiring plate, wherein the wiring conductor has a main body region located on the insulating layer and a plurality of tip regions extending from the main body region so as to extend outward from the insulating layer. The step of preparing the flexible wiring plate to be provided, the insulating layer is fixed to the upper surface of the tubular portion with an adhesive, and the connection terminals for the piezoelectric elements in the plurality of tip regions are connected to the upper surface electrodes of the plurality of piezoelectric elements. The step of preparing the flexible wiring board includes a flexible wiring board mounting step of electrically connecting the layers with a conductive adhesive or solder, respectively, and the step of preparing the flexible wiring board is at least a stage before the flexible wiring board mounting step of the elastic plate. Forming step, said piezoelectric element mounting step And a first method of manufacturing an ultrasonic transducer, which is performed independently of the sealing member installation step.

According to such a first manufacturing method, an ultrasonic transducer having the above configuration can be manufactured at low cost and with good yield.

In the first manufacturing method, before the tubular portion installation step, a protective member provided with an opening for opening the vibration region to the outside is opened to the outside through the opening. A protective member installation step of fixing to the second surface of the elastic plate so as to close the second surface side of the slit portion may be provided.

In the tubular portion installation step, the elastic plate is provided so that the sealing member integrally has a filling portion extending from the base end surface of the tubular portion to the inside of the slit portion in addition to the tubular portion. A process including a process of applying a first polymer material to a tubular portion installation region that surrounds the low-rigidity region in a plan view from the side of one surface to the inside of the slit portion and on the first surface of the elastic plate and curing the first polymer material. It is said that.

In the first manufacturing method, in the elastic plate forming step, the elastic plate is formed so that the elastic plate has a base region that surrounds the entire of the plurality of restraint regions in a plan view.

In this case, in the first manufacturing method, after the piezoelectric element mounting step, the first surface of the restraint region is constrained so as to open the first surfaces of the vibration region, the low rigidity region, and the boundary region. A mass member installation step including a process of fixing the mass member for the region and a process of fixing the mass member for the base region to the base region is provided.

In the first manufacturing method, the step of preparing the flexible wiring board is a sheet-shaped insulating layer forming member forming the insulating layer and a sheet-shaped conductor forming the wiring conductor on the upper surface of the insulating layer forming member. A process of preparing a wiring sheet body in which forming members are laminated, a process of removing unnecessary parts of the conductor forming member by etching to form the wiring conductor having a predetermined shape, and a process of forming the wiring conductor having the main body region and the plurality of the wiring conductors. It is assumed that the processing includes a process of removing unnecessary portions of the insulating layer forming member by etching to form the insulating layer having a predetermined shape so as to have the tip region of the above.

In the tubular portion installation step, the upper surface of the plurality of tubular portions is higher than the first height of the upper surface of the upper surface electrode layer of the piezoelectric element with reference to the first surface of the elastic plate. When the plurality of tubular portions are to be installed so as to be located in, preferably, the step of preparing the flexible wiring plate is performed after the process of forming the insulating layer. When the flexible wiring plate is mounted, the tip portion in the tip region overlaps with the upper surface electrode layer of the corresponding piezoelectric element in a plan view, and the height with respect to the first surface of the elastic plate is the first. It is assumed that the tip region is bent so as to be located at a third height equal to or higher than the first height below the two heights.

In order to achieve the second object, the present invention has an elastic plate having a first surface and a second surface facing one side and the other side in the plate thickness direction, respectively, and vibrating in the plate thickness direction, and the elasticity. A plurality of piezoelectric elements fixed in parallel to the first surface of the plate, a mass member fixed to the first surface of the elastic plate, and a plurality of tubular portions surrounding each of the plurality of piezoelectric elements in a plan view. The elastic plate includes a plurality of vibration regions to which the plurality of piezoelectric elements are mounted, and a plurality of low rigidity surrounding the plurality of vibration regions in a plan view. Between a region, a plurality of restraint regions each surrounding the plurality of low-rigidity regions in a plan view, a base region surrounding the entire of the plurality of restraint regions in a plan view, and one adjacent restraint region and another restraint region. The low rigidity region includes the boundary region located between the adjacent restraint region and the base region and demarcating the boundary of each of the plurality of restraint regions, and the low rigidity region is the vibration located inward in the radial direction of the region. The rigidity is lower than that of the region and the restraint region located outside the radial direction of the region, and the boundary region surrounds the slit portion that separates the one restraint region from the surroundings and the one restraint region. The mass member includes a plurality of restraint region mass members fixed to the plurality of restraint regions, and a base region mass member fixed to the base region. The flexible wiring plate has an insulating layer fixed to the upper surface of the mass member for the restraint region and a wiring conductor provided on the upper surface of the insulating layer, and the wiring conductor is a plurality of piezoelectrics. A method for manufacturing an ultrasonic transducer having a plurality of tip regions electrically connected to the upper surface electrode layer of an element, wherein the conductive elastic plate forming body is etched to obtain the elastic plate. The elastic plate forming step of forming the above, the piezoelectric element mounting step of adhering the lower surface electrode layers of the plurality of piezoelectric elements to the first surface of the plurality of vibration regions with a conductive adhesive, and each of the plurality of restraint regions. A flexible wiring plate comprising a mass member installation step including a process of fixing the mass member for the restraint region and a process of fixing the mass member for the base region to the base region, and a wiring conductor provided on the upper surface of the insulating layer. A flexible wiring plate in which the wiring conductor has a main body region located on the insulating layer and a plurality of tip regions extending outward from the main body region so as to extend outward from the insulating layer. And the above The insulating layer is fixed to the upper surface of the mass member for the restraint region with an adhesive, and the connection terminals for the piezoelectric elements in the plurality of tip regions are electrically connected to the upper surface electrode layers of the plurality of piezoelectric elements by a conductive adhesive or solder, respectively. The step of preparing the flexible wiring board, including the flexible wiring board mounting step of connecting to the flexible wiring board, includes the elastic plate forming step, the piezoelectric element mounting step, and the mass member at least in a stage prior to the flexible wiring board mounting step. Provided is a second method of manufacturing an ultrasonic transducer, which is performed independently of the installation process.

According to such a second manufacturing method, an ultrasonic transducer having the above configuration can be manufactured at low cost and with good yield.

In the second manufacturing method, the step of preparing the flexible wiring board is a sheet-shaped insulating layer forming member forming the insulating layer and a sheet-shaped conductor forming the wiring conductor on the upper surface of the insulating layer forming member. A process of preparing a wiring sheet body in which forming members are laminated, a process of removing unnecessary parts of the conductor forming member by etching to form the wiring conductor having a predetermined shape, and a process of forming the wiring conductor having the main body region and the plurality of the wiring conductors. It is assumed that the processing includes a process of removing unnecessary portions of the insulating layer forming member by etching to form the insulating layer having a predetermined shape so as to have the tip region of the above.

In the mass member installation step, the upper surface of the restraint region mass member is set to a second height higher than the first height of the upper surface of the upper surface electrode layer of the piezoelectric element with reference to the first surface of the elastic plate. When the mass member for the restraint region is to be installed so as to be located, preferably, the step of preparing the flexible wiring plate is performed after the process of forming the insulating layer, the plurality of tips. The tip portion in the region overlaps with the upper surface electrode layer of the corresponding piezoelectric element in the plan view when the flexible wiring plate is mounted, and the height with respect to the first surface of the elastic plate is the second. It is assumed that the tip region is bent so as to be located at a third height equal to or higher than the first height below the height.

In the second manufacturing method, preferably, the mass member installation step involves the plurality of restraint region mass members, the base region mass member, one adjacent restraint region mass member, and another restraint region. Prepare a mass plate including a bridge between restraint regions that connects the upper ends of the mass members for mass members and a bridge between restraint regions / base regions that connects the upper ends of adjacent mass members for restraint regions and mass members for base regions. The process of fixing the mass plate to a predetermined position on the first surface of the elastic plate, the process of cutting the inter-constraint region bridge and the inter-constraint region / base region bridge, and the mass for the plurality of restraint regions. It is assumed that the member and the mass member for the base region are separated from each other.

According to such a configuration, it is possible to simplify and facilitate the installation process of the plurality of mass members for the restraint region and the mass members for the base region.

For example, the process of preparing the mass plate includes a process of preparing a plate-shaped metal block having a thickness corresponding to the height of the mass member for the restraint region and the mass member for the base region, and a process of preparing one side of the metal block. It includes a process of half-etching the bridge between the restraint regions and the region corresponding to the bridge between the restraint regions / the base regions from the surface.

In the first and second manufacturing methods, preferably, the step of preparing the flexible wiring board is at least one of the regions of the wiring conductors that form the main body region after the process of forming the wiring conductors. It may have a process of installing an insulating cover layer so as to cover the portion.

In the first and second manufacturing methods, the low-rigidity region is provided along the outer peripheral edge of the vibration region and is open to the side of the first surface, or along the outer peripheral edge of the vibration region. When the plurality of openings provided are a plurality of openings in which a connecting portion is left between the openings adjacent in the circumferential direction, the elastic plate forming step is performed by etching. It is configured to form the slit portion and the groove or the plurality of openings in the low rigidity region.

In the first and second manufacturing methods, the first surface of the low-rigidity region is such that the first surface of the low-rigidity region is closer to the second surface than the first surface of the vibration region and the restraint region. It is a concave thin-walled region that opens to the side, and is a raised portion lower than the first surface of the vibration region and the restraint region on the bottom surface of the thin-walled region, and adheres in cooperation with the inner surface of the thin-walled region. A ridge portion for forming the agent retention region is provided, and the piezoelectric element overlaps with the vibration region in a plan view, and is joined to the first surface of the vibration region by an insulating adhesive, and the central portion. An extending portion that extends outward in the radial direction and ends in the low-rigidity region in a plan view and is joined to the first surface of the low-rigidity region by a conductive adhesive disposed in the adhesive retention region. When the above is obtained, the etching in the elastic plate forming step includes a full etching process for forming the slit portion and a half from the side of the first surface with respect to the region corresponding to the low rigidity region. It includes a half-etching process for forming the low-rigidity region, which is a concave thin-walled region by etching.

In the half-etching process, the region corresponding to the vibration region and the region corresponding to the restraint region are covered with a mask, and the region corresponding to the raised portion is covered with a mask having a width narrower than twice the amount of side etching. It is configured to leave the vibration region and the raised portion lower than the restraint region on the bottom surface of the concave thin-walled region while making the low-rigidity region a concave thin-walled region that opens to the first surface side. To.

In order to achieve the second object, the present invention has an elastic plate having a first surface and a second surface facing one side and the other side in the plate thickness direction, respectively, and vibrating in the plate thickness direction, and the elasticity. A plurality of piezoelectric elements fixed in parallel to the first surface of the plate and a flexible wiring plate fixed to the first surface of the elastic plate are provided, and the elastic plate is respectively mounted with the plurality of piezoelectric elements. A plurality of vibration regions, a plurality of low-rigidity regions surrounding the plurality of vibration regions in a plan view, a plurality of restraint regions surrounding the plurality of low-rigidity regions in a plan view, a restraint region, and the one. The low-rigidity region includes the vibration region located inward in the radial direction of the region and the radial outside of the region, including the boundary region that partitions the outer region located radially outward from the restraint region of the region. The elasticity is lower than that of the restraint region located in the direction, and the boundary region is a slit portion that divides the one restraint region and the outer region, and the one restraint region is mechanically divided into the outer region. A method for manufacturing an ultrasonic transducer having a bridge portion for connecting the elastic plates, the elastic plate forming step of forming the elastic plate by etching a conductive elastic plate forming body, and the above-mentioned. Prepared an elastic element mounting step in which the lower surface electrode layers of the plurality of piezoelectric elements are bonded to the first surface of a plurality of vibration regions with a conductive adhesive, and a flexible wiring plate in which a wiring conductor is provided on the upper surface of the insulating layer. The step of fixing the insulating layer to a predetermined position on the first surface of the elastic plate with an adhesive, and the tip portions of the plurality of wiring conductors are conductive to the corresponding upper surface electrode layer of the piezoelectric element. It has a flexible wiring board mounting process including an electrical connection process of electrically connecting with an adhesive or solder, and the step of preparing the flexible wiring board is independent of the elastic plate forming step and the piezoelectric element mounting step. A third method of manufacturing an ultrasonic transducer to be performed is provided.

According to such a third manufacturing method, the ultrasonic transducer having the above configuration can be manufactured at low cost and with good yield.

In the third manufacturing method, preferably, in the flexible wiring board mounting step, an insulating resin is applied between the tips of the plurality of wiring conductors and the corresponding piezoelectric elements before the electrical connection process. It may be provided with an insulating resin installation process.

In this case, the conductive adhesive or the solder in the electrical connection process is in a state where the insulating resin is interposed between the conductive adhesive or the solder and the first surface of the elastic plate. The tip portions of the plurality of wiring conductors are provided so as to be electrically connected to the upper surface electrode layer of the corresponding piezoelectric element.

FIG. 1 is a vertical cross-sectional view of the ultrasonic transducer according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 1, and some of the constituent members are omitted for ease of understanding. FIG. 3 is an enlarged view of Part III in FIG. FIG. 4 is an enlarged view of part IV in FIG. 2, and the illustration of the sealing member is omitted for ease of understanding. FIG. 5 is a partially enlarged plan view of the ultrasonic transducer according to the first modification of the first embodiment, showing a state in which a part of the constituent members is removed. FIG. 6 is a partially enlarged plan view of the ultrasonic transducer according to the second modification of the first embodiment, showing a state in which a part of the constituent members is removed. FIG. 7 is a plan view of the ultrasonic transducer according to the third modification of the first embodiment, showing a state in which a part of the constituent members is removed. FIG. 8 is a plan view of the ultrasonic transducer according to the fourth modification of the first embodiment, showing a state in which a part of the constituent members is removed. 9 (a) to 9 (c) are process diagrams of a method for manufacturing an ultrasonic transducer according to the first embodiment. FIG. 10 is a process diagram of the manufacturing method following FIG. 9 (c). FIG. 11 is a process diagram of the manufacturing method following FIG. FIG. 12 is a process diagram of the manufacturing method following FIG. 13 (a) to 13 (e) are process diagrams of the process of preparing the flexible wiring board in the manufacturing method. FIG. 14 is a process diagram of the manufacturing method following FIG. FIG. 15 is a process diagram of the manufacturing method following FIG. FIG. 16 is a process diagram of the manufacturing method following FIG. FIG. 17 is a vertical cross-sectional view of the ultrasonic transducer according to the fifth modification of the first embodiment. FIG. 18 is a vertical cross-sectional view of the ultrasonic transducer according to the sixth modification of the first embodiment. FIG. 19 is a vertical cross-sectional view of the ultrasonic transducer according to the seventh modification of the first embodiment. FIG. 20 is a vertical cross-sectional view of the ultrasonic transducer according to the eighth modification of the first embodiment. FIG. 21 is a vertical cross-sectional view of the ultrasonic transducer according to the second embodiment of the present invention. FIG. 22 is a cross-sectional view taken along the line XXII-XXII in FIG. 21, and some of the constituent members are omitted for ease of understanding. FIG. 23 is an enlarged view of part XXIII in FIG. FIG. 24 is a process diagram of a method for manufacturing an ultrasonic transducer according to the second embodiment. FIG. 25 is a process diagram of the manufacturing method following FIG. 24. FIG. 26 is a process diagram of the manufacturing method following FIG. 25. FIG. 27 is a process diagram of the manufacturing method following FIG. 26. FIG. 28 is a process diagram of the manufacturing method following FIG. 27. FIG. 29 is a process diagram of the manufacturing method following FIG. 28. FIG. 30 is a process diagram of a method for manufacturing an ultrasonic transducer according to the second embodiment, and is a plan view of a state in which a mass plate is fixed. FIG. 31 is a vertical cross-sectional view taken along the line XXXI-XXXI in FIG. FIG. 32 is an enlarged view of part XXXII in FIG. 31. FIG. 33 is an enlarged view corresponding to FIG. 32, and shows a state in which the bridge between the restraint regions and the bridge between the restraint regions / base regions in the mass plate are cut. FIG. 34 is a vertical cross-sectional view of the ultrasonic transducer according to the first modification of the second embodiment. FIG. 35 is a vertical cross-sectional view of the ultrasonic transducer according to the second modification of the second embodiment. FIG. 36 is a partial vertical sectional view of the ultrasonic transducer according to the third embodiment of the present invention. FIG. 37 is a plan view of the ultrasonic transducer according to the third embodiment. 38 (a) to 38 (c) are process diagrams of a method for manufacturing an ultrasonic transducer according to the third embodiment. FIG. 39 is a partial vertical sectional view of the ultrasonic transducer according to the first modification of the third embodiment. FIG. 40 is a partial vertical sectional view of the ultrasonic transducer according to the second modification of the third embodiment. FIG. 41 is a vertical sectional view of an ultrasonic transducer manufactured by the manufacturing method according to the fourth embodiment of the present invention. FIG. 42 is a cross-sectional plan view taken along the line XXXXII-XXXXII in FIG. 41, and is shown in a state where some constituent members are not shown. FIG. 43 is an enlarged view of part XXXXIII in FIG. 41. 44 (a) to 44 (d) are process diagrams of a process of preparing a flexible wiring board in the manufacturing method according to the fourth embodiment. FIG. 45 is a process diagram showing an insulating layer fixing process in the flexible wiring board mounting process of the manufacturing method according to the fourth embodiment. FIG. 46 is a process diagram showing an electrical connection process in the flexible wiring board mounting process. FIG. 47 is an enlarged view of part XXXXVII in FIG. 46.

Embodiment 1
Hereinafter, an embodiment of the ultrasonic transducer according to the present invention will be described with reference to the accompanying drawings.
FIG. 1 shows a vertical cross-sectional view of the ultrasonic transducer 1A according to the present embodiment.
Further, FIGS. 2 and 3 show a cross-sectional view taken along the line II-II in FIG. 1 and an enlarged view of part III, respectively.
In FIG. 2, the following closed portion 44 and the following sound absorbing material 50 in the ultrasonic transducer are not shown for ease of understanding.

The ultrasonic transducer 1A according to the present embodiment is suitably used as a phased array sensor used for detecting the shape of an object, detecting an object over a wide range, and the like.

Specifically, as shown in FIGS. 1 to 3, the ultrasonic transducer 1A includes an elastic plate 10 having a first surface 10a and a second surface 10b facing one side and the other side in the plate thickness direction, respectively. A seal having a plurality of piezoelectric elements 30 fixed to the first surface 10a of the elastic plate 10 in parallel in the plate surface direction, and a plurality of tubular portions 42 surrounding each of the plurality of piezoelectric elements 30 in a plan view. It includes a member 40 and a flexible wiring plate 80 that serves as a voltage supply path for the plurality of piezoelectric elements 30.

The elastic plate 10 is made of a metal plate such as stainless steel, Ni-Fe alloy, aluminum alloy, titanium alloy, or various materials such as carbon fiber reinforced plastic and ceramics as long as it has elasticity that can vibrate in the plate thickness direction. obtain.
The elastic plate 10 has a thickness of, for example, 0.03 mm to 0.1 mm.
In the present embodiment, the elastic plate 10 is formed of a conductive metal plate.

The piezoelectric element 30 has a piezoelectric main body made of PZT (lead zirconate titanate), and a pair of upper surface electrode layers and lower surface electrode layers arranged on both sides of the piezoelectric body in the thickness direction.
The piezoelectric body has a thickness of, for example, 0.05 mm to 0.3 mm, and the upper surface electrode layer and the lower surface electrode layer are formed of, for example, Ag or Au having a thickness of 0.05 μm to several μm.

The plurality of piezoelectric elements 30 are fixed in parallel to the first surface 10a with the lower surface electrode layer facing the first surface 10a of the elastic plate 10.

Specifically, as shown in FIGS. 1 to 3, the elastic plate 10 surrounds a plurality of vibration regions 12 to which the plurality of piezoelectric elements 30 are mounted, and the plurality of vibration regions 12 in a plan view. A plurality of low-rigidity regions 26, a plurality of restraint regions 14 surrounding the plurality of low-rigidity regions 26 in a plan view, and an outer side located radially outward from one restraint region 14 and the one restraint region 14. A boundary region 16 for partitioning the region is provided.

As shown in FIG. 2, the ultrasonic transducer 1A according to the present embodiment has m (5 in the illustrated embodiment) of the elastic plates 10 arranged along the first plate surface direction D1 of the elastic plate 10. The restraint region group 14A formed by the restraint region 14 is provided in n rows (3 rows in the illustrated embodiment) in the second plate surface direction D2 orthogonal to the first plate surface direction D1 to appear. It has × n (5 × 3 = 15 in the illustrated embodiment) of the restraint regions 14.

Similarly, m × n of the plurality of low-rigidity regions 26 in which the plurality of restraint regions 14 are surrounded are also provided, and the plurality of vibration regions 12 in which the plurality of low-rigidity regions 26 are each surrounded are also m × n. N pieces are provided.
A piezoelectric element 30 is attached to each of the m × n vibration regions 12.

In the present embodiment, as shown in FIG. 2, the elastic plate 10 has a base region 11 that surrounds the entire of the plurality of restraint regions 14 in a plan view.

In this case, among the plurality of restraint areas 14, the restraint area 14 located on the outermost circumference, for example, the restraint area 14 (1-1) located in the first row from the top and the first column from the left in FIG. , Constrained area 14 adjacent to the right side (constrained area 14 (1-2) located in the first row from the top and second column from the left), constrained area 14 adjacent to the lower side (second row from the top and located in the second column from the left) The restraint region 14 (2-1)) located in the first row from the left and the base region 11 adjacent to the upper side and the left side serve as the outer region facing the boundary region 16.

Then, for the constrained region 14 (2-2) located in the second row from the top and the second column from the left in FIG. 2, for example, the constrained region 14 (2-2) whose circumference is surrounded by other constrained regions, is on the upper side. Adjacent constrained area 14 (first row from top and second column from left), constrained area 14 adjacent to the right (second row from top and third column from left) Constrained area 14 (2-3)), constrained area 14 adjacent to the lower side (constrained area 14 (3-2) in the third row (bottom row) from the top and second column from the left), and on the left side The adjacent restraint region 14 (constraint region 14 (2-1) in the second row from the top and the first column from the left) is the outer region facing the boundary region 16.

In the present embodiment, as shown in FIG. 2, the plurality of restraint regions 14 are arranged in a grid pattern, but of course, the plurality of vibration regions 12 are limited to such an arrangement. Instead, they can be arranged in a staggered pattern or in a radial pattern.

In the present embodiment, as described above, the elastic plate 10 is a conductive metal plate, and the piezoelectric element 30 has the elastic plate whose lower surface electrode layer is formed by the conductive adhesive 38 (see FIG. 3). It is mechanically fixed to the first surface 10a of the elastic plate 10 in a state of being electrically connected to the first surface 10a of the elastic plate 10.

FIG. 4 is an enlarged view of part IV in FIG. 2, showing a state in which the sealing member 40 is omitted for the sake of comprehension.
As shown in FIG. 4, the boundary region 16 divides a restraint region 14 in which the boundary region 16 defines an outer peripheral edge and the outer region adjacent to the radial outer side of the one restraint region 14. It has a slit portion 17 and a bridge portion 18 that maintains a mechanical connection of the one restraint region 14 to the outer region.

The sealing member 40 is formed of, for example, a polymer material such as silicone.
As shown in FIG. 3, in the present embodiment, the tubular portion 42 of the sealing member 40 is joined to the first surface 10a of the elastic plate 10 so that the base end surface covers the boundary region 16. There is.

As described above, in the ultrasonic transducer 1A according to the present embodiment, a plurality of vibration regions 12 in a state surrounded by the low-rigidity region 26 are provided on one elastic plate 10, and the plurality of vibrations are provided. A plurality of piezoelectric elements 30 are mounted on each of the regions 12, and it is possible to realize an arrangement as close as possible between the plurality of vibration regions 12 vibrated by the plurality of piezoelectric elements 30. Further, the slit portion 17 of the boundary region 16 effectively prevents or reduces the vibration of the one vibration region 12 from propagating to the outer region located radially outward of the one vibration region 12. Can be done.

Therefore, it is effective that low frequency (for example, 30 kHz to 40 kHz) ultrasonic waves can be radiated from the piezoelectric element 30 and the vibration region 12, and that a grating lobe phenomenon occurs between the plurality of piezoelectric elements 30. Can be prevented or reduced.

As shown in FIG. 3, the flexible wiring board 80 has an insulating layer 82 and a wiring conductor 85 provided on the upper surface of the insulating layer 82.

The insulating layer 82 is formed of, for example, a polyimide having a thickness of about 18 μm to 25 μm.
The wiring conductor 85 is formed of, for example, Cu / Au having a thickness of about 12 μm to 18 μm.

As shown in FIG. 3, in the present embodiment, the insulating layer 82 is fixed to the upper surface of the tubular portion 42 of the sealing member 40 by an adhesive.

As shown in FIG. 3, in the present embodiment, the wiring conductor 85 has a main body region 85a located on the insulating layer 82 and a plurality of tips electrically connected to the plurality of piezoelectric elements 30. It has a region 85b.

The tip region 85b is the insulating layer so as to form a connection terminal for the piezoelectric element that is electrically connected to the upper surface electrode layer of the piezoelectric element 30 to which the tip corresponds via a conductive adhesive or solder 87. It extends outward from 82.

The main body region 85a has a top electrode layer pad 86 (see FIG. 2) that forms a connection terminal with the outside at a base end portion.

As shown in FIG. 2, in the present embodiment, the wiring conductor 85 has a plurality of conductors individually connected to the upper surface electrode layers of the plurality of piezoelectric elements 30, and the plurality of conductors are individually connected to each other. Each of the plurality of piezoelectric elements 30 can be individually operated via the above.

The flexible wiring board 80 may be deformed so as to have a wiring conductor having a single main body region and a plurality of tip regions branched from the single main body region instead of the wiring conductor 85. It is possible.
In this case, the plurality of piezoelectric elements 30 are integrally operated via the wiring conductor.

As shown in FIG. 3, in the present embodiment, the piezoelectric element 30 is configured such that the upper surface of the upper surface electrode layer is located at the first height with respect to the first surface 10a of the elastic plate 10. On the other hand, the tubular portion 42 is configured such that the upper surface thereof is located at a second height higher than the first height with respect to the first surface 10a of the elastic plate 10.

In this case, in the tip region 85b of the wiring conductor 85, the connection terminal for the piezoelectric element is polymerized on the upper surface electrode layer of the piezoelectric element 30 in a plan view, and the first surface 10a of the elastic plate 10 is used as a reference. It is configured to be located at a third height below the second height position and above the first height.

According to such a configuration, the connection work between the connection terminal for the piezoelectric element and the upper surface electrode layer of the piezoelectric element 30 can be easily performed in a state where the insulating layer 82 is fixed to the upper surface of the tubular portion 42. it can.

In the present embodiment, as shown in FIG. 3, the tip region 85b has a front-low-back-high inclined portion that is located downward toward the tip side, but of course. Alternatively, it is possible to have a vertical extension site along a substantially vertical direction.

As described above, in the present embodiment, the lower surface electrode layers of the plurality of piezoelectric elements 30 are electrically connected to the conductive elastic plate 10 via the conductive adhesive 38.

In this case, as shown in FIG. 2, the flexible wiring board 80 is further provided with a pad 89 for the lower surface electrode layer. The lower surface electrode layer pad 89 can be connected to the outside in a state where one end side is electrically connected to the elastic plate 10.

In the present embodiment, as shown in FIGS. 2 and 3, the flexible wiring board 80 is the main body of the wiring conductor 85 in order to prevent the wiring conductor 85 from unexpectedly coming into contact with the outside. It has an insulating cover layer 83 that covers a part or all of the portion of the region 85a excluding the upper surface electrode layer pad 86.

As described above, in the ultrasonic transducer 1A according to the present embodiment, the flexible wiring board 80 is not directly fixed to the elastic plate 10, but is sealed in a state of being separated from the elastic plate 10. It is fixed to the upper surface of the tubular portion 42 of the member 40.
Therefore, the flexible wiring board 80 can effectively prevent or reduce the deterioration of the vibration characteristics of the vibration region 12.

As shown in FIG. 3, in the present embodiment, the sealing member 40 is integrated from the base end surface of the tubular portion 42 into the inside of the slit portion 17 in addition to the plurality of tubular portions 42. It has a filling portion 41 extending to.

According to such a configuration, the posture of the restraint region 14 is obtained while obtaining the effect of effectively preventing or reducing the vibration of one vibration region 12 from propagating to the other adjacent vibration regions 12 by the slit portion 17. Stabilization, and by extension, stabilization of the operation of the vibration region 12 can be achieved.

As shown in FIGS. 1 and 3, the sealing member 40 further has a plurality of closing portions 44 that close the openings on the free end side of the plurality of tubular portions 42, respectively.

As shown in FIGS. 1 and 3, the ultrasonic transducer 1A according to the present embodiment further includes a sound absorbing material 50 that covers the upper electrode layer of the piezoelectric element 30.

More specifically, as described above and as shown in FIG. 3, the upper surface of the tubular portion 42 is located at a second height higher than the first height at which the upper surface electrode layer of the piezoelectric element 30 is located. The closing portion 44 is provided so as to have a gap between the closed portion 44 and the upper surface electrode layer of the piezoelectric element 30.

On top of that, the accommodating space for accommodating the piezoelectric element 30 surrounded by the first surface 10a of the elastic plate 10, the tubular portion 42, and the closing portion 44 is formed of an effervescent resin such as effervescent silicone. The sound absorbing material 50 is filled.

By providing the sound absorbing material 50, leakage of ultrasonic waves from the vibration region 12 to the rear (the first surface 10a side with respect to the plate thickness direction of the elastic plate 1) can be prevented or reduced, and burst-shaped ultrasonic waves can be prevented or reduced. The reverberation of the ultrasonic wave can be effectively suppressed after the ultrasonic wave is emitted.

As shown in FIGS. 1 and 3, the ultrasonic transducer 1A according to the present embodiment further has a reinforcing plate 60 fixed to the outer surface of the closing portion 44 of the sealing member 40.
The reinforcing plate 60 is formed of a rigid plate such as stainless steel.

By providing the reinforcing plate 60, the strength of the ultrasonic transducer 1A can be increased without impairing the vibration characteristics.

As shown in FIGS. 1 and 3, the ultrasonic transducer 1A according to the present embodiment is a protective member 70 joined to the second surface 10b of the elastic plate 10, and the vibration region 12 is formed. A protective member 70 having an opening 72 that opens outward is provided.
The protective member 70 is made of, for example, silicone having a thickness of about 0.5 mm to 1.5 mm.

By providing the protective member 70, the elastic plate 10 can be protected without impairing the vibration characteristics.

The ultrasonic transducer 1A further has a rigid protective plate 75 bonded to the outer surface of the protective member 70.
The protective plate 75 is provided with a through hole 77 at a position corresponding to the opening 72 of the protective member 70.
The protective plate 75 is formed of, for example, a metal plate having a thickness of about 0.1 mm to 0.5 mm, such as stainless steel, Ni-Fe alloy, aluminum alloy, or titanium alloy.

By providing the protective plate 75, it is possible to effectively prevent or reduce damage to the protective member 70 and effectively suppress the protective member 70 from vibrating unexpectedly.

In the present embodiment, as shown in FIG. 4, the slit portions 17 are located on both sides of the second plate surface direction D2 of the one piezoelectric element 30 mounted in the vibration region 12 in the one restraint region 14. The pair of first plate surface direction slits 17a extending along the first plate surface direction D1 and the first piezoelectric element 30 located on both sides of the first plate surface direction D1 are located in the second plate surface direction D2. It includes a pair of second plate surface direction slits 17b extending along the line.

The pair of first plate surface direction slits 17a is longer than the first plate surface direction length 30a of the one piezoelectric element 30, and the pair of second plate surface direction slits 17b is the second of the one piezoelectric element 30. It is made longer than the plate surface direction length 30b, and is defined at four locations defined between the ends of the first plate surface direction slit 17a and the second plate surface direction slit 17b adjacent to each other in the circumferential direction. The bridge portion 18 is provided.

According to such a configuration, the plurality of restraint regions 14 can be stably held while effectively preventing vibration from propagating between the plurality of piezoelectric elements 30 arranged in a rectangular shape.

Further, in the present embodiment, as described above, only a single boundary region 16 exists between the adjacent restraint regions 14, and the slit 17 of the single boundary region 16 is adjacent to the restraint region. It demarcates the outer perimeters of both sides of 14.

According to such a configuration, it is possible to reduce the installation area of the plurality of restraint regions 14 as much as possible while effectively preventing vibration propagation between the plurality of piezoelectric elements 30.

The slit portion 17 and the bridge portion 18 may have various configurations.
FIG. 5 shows a partially enlarged plan view of the ultrasonic transducer 1B according to the first modification having the slit portion 21 and the bridge portion 22 having different configurations.
Also in FIG. 5, the sealing member and the sound absorbing material are not shown.

In the first modification 1B shown in FIG. 5, the slit portion 21 has an arc shape.
The four slit portions 21 surround one restraint region 14, and the bridge portion 22 is provided between the two slit portions 21 adjacent in the circumferential direction.

Further, FIG. 6 shows a partially enlarged plan view of the ultrasonic transducer 1C according to the second modification provided with the slit portion 23 and the bridge portion 24 having further different configurations.
Also in FIG. 6, the sealing member and the sound absorbing material are not shown.

In the second modification 1C shown in FIG. 6, the slit portion 23 has a substantially L-shape in a plan view.
The four slit portions 23 surround one restraint region 14.

Specifically, the two L-shaped slits 23 adjacent to each other in the circumferential direction overlap in the circumferential direction in a state where a part 23a of one slit 23 is located inward in the radial direction with a part 23b of the other slit 23. The radial gap between a part 23a of the one slit 23 and a part 23b of the other slit 23 forms the bridge portion 24.

In the slit portions 17 (21, 23) and the bridge portions 18 (22, 24) having various configurations, preferably, when the circumferential length of the boundary region 16 is L, the plurality of slit portions 17 (21). , 23) can be configured so that the total length La in the circumferential direction satisfies La ≧ 0.9 × L.

As described above, in the ultrasonic transducer 1A according to the present embodiment, the low-rigidity region 26 having a lower rigidity than the vibration region and the restraint region is provided around the vibration region. ..

By providing such a configuration, the vibration characteristics of the vibration region 12 can be enhanced.
Therefore, it is possible to generate low-frequency sound waves while reducing the size of the vibration region 12 and reducing the arrangement pitch of the plurality of vibration regions 12.

In the present embodiment, as shown in FIGS. 2 and 4, the outer shape of the vibration region 12 and the outer shape of the piezoelectric element 30 are the same, and the first surface 10a of the elastic plate 10 is said to be the same. A groove 27 is provided in a region along the outer peripheral edge of the vibration region 12, and the low-rigidity region 26 is formed by the groove 27.

According to such a configuration, the groove 27 forms the low-rigidity region 26, and the groove 27 can also be used as an alignment mark when mounting the piezoelectric element 30 in the vibration region 12.

FIG. 7 shows a partially enlarged plan view of the ultrasonic transducer 1D according to the third modification in which the low-rigidity region 26 is formed by a different structure.
Also in FIG. 7, the sealing member and the sound absorbing material are not shown.

In the third modification 1D shown in FIG. 7, in the region of the elastic plate 10 along the outer peripheral edge of the vibration region 12, the opening 28a that divides the inside and outside of the vibration region 12 and the inside and outside of the vibration region 12 The connecting portions 28b are provided alternately in the circumferential direction, and the low-rigidity region 26 is formed by the opening 28a and the connecting portion 28b.
The opening 28a and the connecting portion 28b can also be used as an alignment mark when mounting the piezoelectric element 30 in the vibration region 12, similarly to the groove 27.

In the present embodiment, the vibration region 12 has a circular shape in a plan view, and the piezoelectric element 30 has a circular shape in a plan view having the same shape as this. It is not limited to the form.
FIG. 8 is a plan view of the ultrasonic transducer 1E according to the fourth modification provided with the vibration region 12 having a rectangular shape in a plan view and the piezoelectric element 30, the closing portion 44 of the sealing member 40 and the sound absorbing portion. The plan view in the state where the material 50 was deleted is shown.

Next, an example of a method for manufacturing the ultrasonic transducer 1A will be described.
The manufacturing method includes an elastic plate forming step (FIGS. 9A and 9B) in which the conductive elastic plate forming body 110 is etched to form the elastic plate 10.

The etching in the elastic plate forming step includes forming a groove 27 in a region of the first surface 10a of the elastic plate 10 along the outer peripheral edge of the vibration region 12 (FIG. 9A) and the slit portion. It is configured to form 17 (FIG. 9 (b)).

In the present embodiment, the groove 27 is first formed by half etching, and then the slit portion 17 is formed, but the formation order of the groove 27 and the slit portion 17 does not matter.

Further, when the low-rigidity region 26 is exposed by the plurality of openings 28a as in the modified example 1D, the etching in the elastic plate forming step replaces the formation of the groove 27 with the vibration. The plurality of openings 28a along the outer peripheral edge of the region 12 are configured to form the plurality of openings 28a in which the connecting portion 28b is left between the openings 28a adjacent in the circumferential direction. ..

The manufacturing method includes a piezoelectric element mounting step of adhering the lower surface electrode layers of the plurality of piezoelectric elements 30 to the first surface 10a of the plurality of vibration regions 12 with a conductive adhesive 38, respectively.

Specifically, the piezoelectric element mounting step includes a step of applying the conductive adhesive 38 to the first surface 10a of the plurality of vibration regions 12 (FIG. 9 (c)) and the step of applying the conductive adhesive 38 on the conductive adhesive 38. It has a step (FIG. 10) of mounting the piezoelectric element 30 on the surface and curing the conductive adhesive 38.

Reference numeral 39 in FIGS. 9 (a) to 9 (c) is gold plating provided on the first surface 10a of the vibration region 12 before the application of the conductive adhesive 38. This is for improving the reliability of the electrical connection of the vibration region 12 with the first surface 10a.

The manufacturing method further includes a protective member installation step for installing the protective member 70 and a protective plate installation step (FIG. 11) for installing the protective plate 75.

The protective member 70 is fixed to the second surface 10b of the elastic plate 10 so as to close the second surface side of the slit portion 17 while opening the vibration region 12 outward through the opening 72. Will be done.

In the present embodiment, the protective member installation step and the protective plate installation step include a process of preparing the protective member 70 and a protective preassembly in which the protective plate 75 is adhered to the outer surface of the protective plate 70 in advance. And a process of adhering the protective preassembly to the second surface 10b of the elastic plate 10.

As a matter of course, the protective member installation step and the protective plate installation step are performed by adhering the protective member 70 to the second surface 10b of the elastic plate 10 and adhering the protective plate 75 to the outer surface of the protective member 70. It is also possible to transform it so that it has a process of causing it to occur.

Next, the manufacturing method includes a tubular portion installation step for installing the tubular portion 42.
In the tubular portion installation step, as shown in FIG. 12, the tubular portion mold 49 is defined by defining the region where the tubular portion 42 should be provided (the tubular portion installation area) with the upper side open. The process includes a process of installing the elastic plate 10 and a process of applying a first polymer material such as silicone into the tubular portion formwork 49 from the side of the first surface 10a of the elastic plate 10 and curing the elastic plate 10.

The upper surface of the tubular portion 42 is located at a second height higher than the first height of the upper surface of the upper surface electrode layer of the piezoelectric element 30 with reference to the position of the first surface 10a of the elastic plate 10. Is provided in.

As described above, in the present embodiment, the sealing member 40 has the filling portion 41 extending integrally from the base end surface of the tubular portion 42 to the inside of the slit portion 17.
In this case, as the first polymer material, for example, a liquid silicone having a relatively low viscosity having a viscosity before curing of about 400 mPa · s to 1000 mPa · s can be preferably used.

As described above, by using a low-viscosity liquid silicone in the state before curing as the first polymer material forming the tubular portion 42 and the filling portion 41, the inside of the slit portion 17 and the tubular shape are formed. The first polymer material can be filled in the part installation area while effectively preventing or reducing the occurrence of gaps.

At this time, the opening on the lower side of the slit portion 17 (the second surface side of the elastic plate) is closed by the protective member 70.
Therefore, even if the viscosity of the first polymer material injected into the slit portion 17 before curing is low, the first polymer material is on the lower side (second surface side) of the slit portion 17. Outflow from the opening is effectively prevented.

When the first polymer material is a thermosetting type, heating at a curing temperature (for example, 100 ° C. to 150 ° C.) is performed after the first polymer material is applied to the tubular portion installation region. Therefore, the curing treatment can be performed.

The manufacturing method further includes a step of preparing the flexible wiring board 80 and a step of mounting the flexible wiring board 80 after the step of installing the tubular portion.

The step of preparing the flexible wiring board 80 is executed independently of the elastic plate forming step, the piezoelectric element mounting step, the protective member installation step, the protective plate installation step, and the tubular portion installation step.

That is, the step of preparing the flexible wiring board 80 can be executed before the elastic plate forming step, can be executed after the tubular portion installation step, or these. It is also possible to execute in parallel with the process of.

Specifically, in the step of preparing the flexible wiring board 80, the sheet-shaped conductor forming the wiring conductor 85 on the upper surface of the sheet-shaped insulating layer forming member 182 forming the insulating layer 82 and the insulating layer forming member 182. It has a process (FIG. 13 (a)) of preparing a wiring sheet body 180 in which the forming members 185 are laminated.

The insulating layer forming member 182 is, for example, a polyimide having a thickness of about 18 μm to 25 μm.
The conductor forming member 185 is, for example, Cu / Au having a thickness of about 12 μm to 18 μm.

The step of preparing the flexible wiring board 80 includes a process of etching and removing an unnecessary portion of the conductor forming member 185 to form the wiring conductor 85 having a predetermined shape (FIG. 13 (b)).

The manufacturing method further includes a process of removing unnecessary portions of the insulating layer forming member 182 by etching to form the insulating layer 82 having a predetermined shape (FIG. 13 (d)).

Here, by performing a process of forming the insulating layer 82 having a predetermined shape, the wiring conductor 85 extends outward from the main body region 85a located on the insulating layer 82 and the insulating layer 85a. It is assumed that the tip region 85b is provided (FIG. 13 (d)).

In the step of preparing the flexible wiring board 80, the connection terminal for the piezoelectric element formed by the tip portion of the tip region 85b is further superimposed on the upper surface electrode layer of the corresponding piezoelectric element 30 in a plan view, and the flexible wiring board 80 is prepared. The tip region 85b is bent so that the height of the connection terminal for the piezoelectric element with respect to the first surface 10a of the elastic plate 10 is located at the third height (FIG. 13 (FIG. 13). e)).

As described above, in the present embodiment, the flexible wiring board 80 has the insulating cover layer 83 that covers a predetermined portion of the wiring conductor 85.
Therefore, the step of preparing the flexible wiring board 80 is configured to include the installation process of the insulating cover layer 83.

The installation process of the insulating cover layer 83 can be performed, for example, before the insulating layer forming step (FIG. 13 (c)).
The insulating cover layer 83 can be formed by a photolithography technique using a photosensitive resin such as photosensitive polyimide.

In the flexible wiring board mounting step, the insulating layer 82 is fixed to the upper surface of the tubular portion 42 with an adhesive, and the connection terminal for the piezoelectric element is conductively adhered to the upper surface electrode layer of the corresponding piezoelectric element 30. It includes a process of electrically and mechanically connecting with an agent or solder 87 (FIG. 14).

As described above, in the present embodiment, in the step of preparing the flexible wiring board 80, the flexible wiring board 80 is in a state where the tip region 85b of the wiring conductor 85 is bent.
Therefore, the flexible wiring board mounting process can be easily executed.

The ultrasonic transducer 1A according to the present embodiment has the sound absorbing material 50 as described above.
Therefore, the manufacturing method includes a sound absorbing material installation step of installing the sound absorbing material 50 after the flexible wiring board mounting step (FIG. 15).

The sound absorbing material installation step is configured to apply a foaming resin such as foamable silicone that forms the sound absorbing material 50 into the sound absorbing material installation space surrounded by the tubular portion 42 and cure the sound absorbing material. (Fig. 15).

As described above, in the present embodiment, the sealing member 40 has the closing portion 44.
Therefore, the manufacturing method includes a closing portion installation step of installing the closing portion 44 after the sound absorbing material installation step (FIG. 16).

The closing portion installation step is configured to apply and cure a second polymer material such as silicone so as to cover the tubular portion 42, the sound absorbing material 50, and the flexible wiring board 80.

In this case, the second polymer material is a liquid silicone having a viscosity before curing higher than that of the first polymer material, for example, a highly viscous liquid having a viscosity before curing of about 1000 mPa · s to 100,000 mPa · s. Silicone can be used.

When the second polymer material is a thermosetting type, the curing temperature (for example, 100 ° C. to 150 ° C.) is applied after the second polymer material is applied to the upper surfaces of the tubular portion 42 and the sound absorbing material 50. ), The curing treatment can be performed.

The manufacturing method includes a reinforcing plate installation step of adhering the reinforcing plate 60 to the outer surface of the closing portion 44 after the closing portion 44 (the second sealing member 40b) is installed (FIG. 1). And see FIG. 3).

Instead of this, it is also possible to install the closing portion 44 and the reinforcing plate 60 at the same time.
That is, the closed portion 44 is separately formed, the reinforcing plate 60 is adhered to the outer surface of the closed portion 44, the closed portion with the reinforcing plate is formed in advance, and the closed portion with the reinforcing plate is formed into the tubular portion. It is also possible to install the closing portion and the reinforcing plate 60 by fixing the sound absorbing material 50 and the flexible wiring board 80 so as to cover the 42.

Various modifications can be made to the ultrasonic transducer 1A according to the present embodiment.
17 to 19 show partial longitudinal side views of the ultrasonic transducers 1F to 1H according to the fifth to seventh modifications of the present embodiment, respectively.

As shown in FIG. 17, in the fifth modification 1F, the closing portion 44 and the reinforcing plate 60 are deleted as compared with the ultrasonic transducer 1A according to the present embodiment.

As shown in FIG. 18, in the sixth modification 1G, the sound absorbing material 50 is omitted as compared with the ultrasonic transducer 1A according to the present embodiment.

As shown in FIG. 19, in the seventh modification 1H, the sound absorbing material 50, the closing portion 44, and the reinforcing plate 60 are omitted as compared with the ultrasonic transducer 1A according to the present embodiment. ..

Further, although the ultrasonic transducer 1A according to the present embodiment has a flat plate-shaped protective plate 75 (see FIG. 1 and the like), it is also possible to provide a protective container 175 in place of the protective plate 75. is there.

FIG. 20 shows a vertical cross-sectional view of the ultrasonic transducer 1I according to the eighth modification provided with the protective container 175.

The protective container 175 has a central portion fixed to the outer surface of the protective member 70 and an extending portion extending outward from the central portion, and the opening of the protective member 70 is provided in the central portion. From the peripheral edge of the end wall portion 176 in which the through hole 177 is provided at a position corresponding to 72, and the side wall of the protective member 70, the elastic plate 10 and the sealing member 44 so as to surround the side walls. It has a peripheral wall portion 178 extending in the thickness direction of the ultrasonic transducer 1I.

In the eighth modification, a gap exists between the peripheral wall and the protective member 70, the elastic plate 10, and the side surface of the tubular portion 42, and the closing portion 44 is formed in the gap. The second polymer material to be formed is filled.

Embodiment 2
Hereinafter, other embodiments of the ultrasonic transducer according to the present invention will be described with reference to the accompanying drawings.
FIG. 21 shows a vertical cross-sectional view of the ultrasonic transducer 2A according to the present embodiment.
In addition, FIGS. 22 and 23 show a cross-sectional view and an enlarged view of the XXIII portion along the XXII-XXII line in FIG. 21, respectively.
In the figure, the same members as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted as appropriate.
For ease of understanding, the closing portion 44 and the sound absorbing material 50 are not shown in FIG. 22.

As shown in FIGS. 21 to 23, the ultrasonic transducer 2A according to the present embodiment mainly includes a mass member 210 fixed to the first surface 10a of the elastic plate 10, and also. The ultrasonic transducer 1A according to the first embodiment is provided with a reinforcing plate 260 and a protective plate 275 that are connected to each other via a spacer 250 instead of the reinforcing plate 60 and the protective plate 75. Is different from.

The mass member 210 is fixed to the first surface 10a of the elastic plate 10 so as to open the first surfaces of the vibration region 12, the low rigidity region 26, and the boundary region 16.

In the present embodiment, as shown in FIGS. 21 to 23, the mass member 210 is fixed to the first surface of the restraint region 14 so as to surround the vibration region 12 and the low rigidity region 26 in a plan view. The vibration region mass member 210a and the base region mass member 210b fixed to the base region 11 so as to surround the entire of the plurality of restraint regions 14 in a plan view are included.

The mass member 210 is made of a metal having a thickness of about 0.1 mm to 1.0 mm, such as stainless steel or a Ni-Fe alloy.
The mass member 210 is fixed to a desired position of the elastic plate by spot welding with an adhesive or a laser.

By providing the mass member 210, it is possible to effectively or reduce the vibration of the restraint region 14 due to the vibration propagating from the vibration region 12.

As shown in FIGS. 21 and 23, in the present embodiment, the upper surface of the mass member 210 is from the first surface 10a of the elastic plate 10 rather than the first height at which the upper surface of the piezoelectric element 30 is located. It is provided so as to be located at a second height separated from each other.

In the present embodiment, the tubular portion 44 is the mass member 210a for the restraint region fixed to the one restraint region 14 surrounding the one low-rigidity region 26, and the one restraint region 14. A mass member 210 (mass member 210a for restraint region or mass member 210b for base region) fixed to an outer region (another adjacent restraint region 14 or the adjacent base region 11) facing each other with the boundary region 16 interposed therebetween. ), And the upper surface is located at the same second height as the upper surface of the mass member 210.

Further, the sound absorbing material 50 uses the mass member 210a for the restraint region fixed to the restraint region 14 surrounding the vibration region 12 to which the corresponding piezoelectric element 30 is fixed as a mold, and the piezoelectric element in the mass member 210a. It is filled so as to cover 30, and the upper surface is located at the same second height as the upper surface of the mass member 210a.

As shown in FIGS. 21 to 23, in the present embodiment, the piezoelectric element is in a state where the insulating layer 82 of the flexible wiring board 80 is fixed to the upper surfaces of the mass member 100 and the tubular portion 42. The connection terminal is electrically and mechanically connected to the upper electrode layer of the corresponding piezoelectric element 30 by a conductive adhesive or solder 87.
Therefore, also in the present embodiment, the flexible wiring board 80 can effectively prevent or reduce the deterioration of the vibration characteristics of the vibration region 12.

As shown in FIG. 21, the protective plate 275 has a central portion 276 that is polymerized on the protective member 70 and is provided with the through hole 77 in a plan view, and extends outward from the central portion 276 in the plate surface direction. The central portion 276 is fixed to the outer surface of the protective member 70 in a state where the through hole 77 and the opening 72 are aligned with each other.

The reinforcing plate 260 has a central portion 262 that polymerizes on the elastic plate 10 in a plan view, and an extending portion 264 that extends outward in the plate surface direction from the central portion 262.

Then, the extending portion 264 of the reinforcing plate 260 and the extending portion 278 of the protective plate 275 are connected to each other via a spacer 250 having a predetermined length.
The spacer 250 can be made of metal such as stainless steel, for example.
Here, the predetermined length of the spacer 250 is set according to the thickness of the ultrasonic transducer 2A.

In the present embodiment, as shown in FIG. 21, the spacer 250 is a hollow tubular body, and the reinforcing plate 260 is extended via a screw member 255 inserted in the hollow portion of the spacer 250. The existing portion 264 and the extending portion 278 of the protective plate 275 are connected.

Alternatively, the spacer 250 can be adhered to the extending portion 264 of the reinforcing plate 260 and the extending portion 278 of the protective plate 275.

By connecting the reinforcing plate 260 and the protective plate 275 via the spacer 250 in this way, the strength of the ultrasonic transducer 2A can be improved.

As a matter of course, the configuration in which the reinforcing plate 260 and the protective plate 275 are connected via the spacer 250 can also be applied to the ultrasonic transducer 1A according to the first embodiment.

Next, an example of a method for manufacturing the ultrasonic transducer 2A will be described.
The manufacturing method has the same steps as the manufacturing method in the first embodiment up to the piezoelectric element mounting step (FIG. 10).

The manufacturing method includes, after the piezoelectric element mounting step, a mass member installation step of fixing the mass member 210 to predetermined locations of the restraint region 14 and the base region 11 (FIG. 24).

In the present embodiment, as shown in FIG. 24, the mass member installation step includes a process of fixing the mass member 210a for the restraint region to each of the plurality of restraint regions 14, and the entire of the plurality of restraint regions 14. Includes a process of fixing the base region mass member 210b to a predetermined portion of the base region 11 surrounding the base region 11.

As described above, the restraint region mass member 210a and the base region mass member 210b constituting the mass member 210 are made of a metal having a thickness of about 0.1 mm to 1.0 mm, such as stainless steel or a Ni-Fe alloy. , Adhesive or spot welding with a laser to fix them in place.

The manufacturing method further includes a protective member installation step for installing the protective member 70 and a protective plate installation step (FIG. 25) for installing the protective plate 275.

In the present embodiment, the protective member installation step and the protective plate installation step include a process of preparing the protective member 70 and a protective preassembly in which the protective plate 275 is previously adhered to the outer surface of the protective member 70. And a process of adhering the protective preassembly to the second surface 10b of the elastic plate 10.

As a matter of course, the protective member installation step and the protective plate installation step are performed by adhering the protective member 70 to the second surface 10b of the elastic plate 10 and adhering the protective plate 275 to the outer surface of the protective member 70. It is also possible to transform it so that it has a process of causing it to occur.

The protective member installation step and the protective plate installation step can also be performed before the mass member installation step.

The manufacturing method includes a tubular portion installation step (FIG. 26) in which the front tubular portion 42 is installed after the mass member installation step and the protective member installation step are completed.

Similar to the first embodiment, the tubular portion installation step is configured to integrally form the filling portion 41 in addition to the tubular portion 44 by using the first polymer material. ..

The manufacturing method further includes a step of preparing the flexible wiring board 80 and a step of mounting the flexible wiring board (FIG. 27).

The step of preparing the flexible wiring board 80 is the same as in the first embodiment, that is, the elastic plate forming step, the piezoelectric element mounting step, the protective member installation step, the protective plate installation step, and the tubular portion installation step. It is executed independently of.

The flexible wiring board mounting step includes a process of fixing the insulating layer 82 to the upper surface of the mass member 210 and the upper surface of the tubular portion 42 with an adhesive, and the piezoelectric element 30 corresponding to the connection terminal for the piezoelectric element. It includes a process of electrically and mechanically connecting the top electrode layer with a conductive adhesive or solder 87 (FIG. 27).

Next, the manufacturing method has a sound absorbing material installation step of installing the sound absorbing material 50 (FIG. 28).
At this time, the region where the sound absorbing material 50 should be installed is surrounded by the restraint region mass member 210a, and therefore, foamed so as to cover the piezoelectric element 30 in the space surrounded by the restraint region mass member 210a. The sound absorbing material 50 can be stably installed by filling it with a foamable resin such as silicone.

The manufacturing method includes a step of installing the reinforcing plate 260 after at least the protective plate 275 is installed (FIG. 29).

The reinforcing plate installation step is configured to install the reinforcing plate 260 by connecting the extending portion 278 of the protective plate 275 and the extending portion 264 of the reinforcing plate 260 via the spacer 250. There is.

The manufacturing method includes the closing portion installation step after the reinforcing plate installation step (FIG. 21).

In the present embodiment, as shown in FIGS. 21, 23 and 29, the reinforcing plate 260 is provided with a through hole 263 that communicates the inner surface and the outer surface, and the closing portion installation step is performed. The second polymer material is injected from the outside through the through hole 263 of the reinforcing plate 260.
According to such a configuration, the thickness of the closed portion 44 can be formed with good controllability.

As described above, in the present embodiment, the mass member installation step includes a process of fixing the restraint region mass member 210a to each of the plurality of restraint regions 14, and the base region 11 at a predetermined position for the base region. It includes a process of fixing the mass member 210b.

Here, the plurality of restraint region mass members 210a and the base region mass member 210b are separate bodies, respectively, and therefore, the plurality of restraint region mass members 210a and the base region mass member 210b. Alignment processing and fixing processing are required for each of the above.

In this regard, if a mass plate 200 in which the plurality of mass members 210a for the restraint region and the mass member 210b for the base region are integrally connected via the following bridges 215 and 216 is used, the mass member installation step can be performed. It can be simplified and speeded up.

FIG. 30 shows a plan view of a preassembly in which the mass plate 200 is fixed to the elastic plate 10 after the piezoelectric element mounting step.
In addition, FIGS. 31 and 32 show a cross-sectional view taken along the line XXXI-XXXI in FIG. 30, and an enlarged view of the XXXII portion in FIG. 31, respectively.

As shown in FIGS. 30 to 32, the mass plate 200 includes the plurality of restraint region mass members 210a, the base region mass member 210b, one adjacent restraint region mass member 210a, and other restraints. The inter-constraint region bridge 215 connecting the upper ends of the mass member 210a for the region and the restraint region / inter-base region bridge 216 connecting the upper ends of the adjacent mass member 210a for the restraint region and the mass member 210b for the base region. have.

The restraint region inter-bridge 215 and the restraint region / base region inter-bridge 216 are made thinner than the restraint region mass member 210a and the base region mass member 210b so as to be easily broken.

The mass plate 200 is, for example, a plate-shaped metal block such as stainless steel having a thickness (for example, 0.2 mm to 1.0 mm) corresponding to the height of the restraint region mass member 210a and the base region mass member 210b. Can be efficiently formed by half-etching the region corresponding to the restraint region bridge 215 and the restraint region / base region bridge 216 from one surface of the metal block.

The restraint region-to-base region bridge 215 and the restraint region / base region-to-base region bridge 216 can have a thickness of, for example, about 0.03 mm to 0.07 mm.

The mass member installation step using the mass plate 200 includes a process of fixing the mass plate 200 to the first surface 10a of the elastic plate 10 at a predetermined position, a bridge between the restraint regions 215, and the restraint region / base region. It is assumed that the bridge 216 is cut to separate the plurality of restraint region mass members 210a and the base region mass member 210b.

FIG. 33 shows a vertical cross-sectional view corresponding to FIG. 32 in a state where the restraint region bridge 215 and the restraint region / base region bridge 216 are cut.

The restraint region-to-base region bridge 215 and the restraint region / base region-to-base region bridge 216 can be cut, for example, by irradiating a laser beam.

According to the mass member installation step using the mass plate 200, when installing the mass members 210a and 210b, it is only necessary to perform the alignment process and the fixing process once, which simplifies the installation of the mass members 210a and 210b and increases the speed. Can be achieved.

Various modifications can be made to the ultrasonic transducer 2A according to the present embodiment.
34 and 35 show vertical cross-sectional views of the ultrasonic transducers 2B and 2C according to the first and second modifications of the present embodiment, respectively.

As shown in FIG. 34, the first modification 2B includes the protective container 175 instead of the protective plate 275 as compared with the ultrasonic transducer 2A according to the present embodiment.

As shown in FIG. 35, the second modification 2C includes the protective plate 75 instead of the protective plate 275 and the reinforcing plate, as compared with the ultrasonic transducer 2A according to the present embodiment. 260 has been deleted.

Embodiment 3
Hereinafter, other embodiments of the ultrasonic transducer according to the present invention will be described with reference to the accompanying drawings.
36 and 37 show a partial vertical sectional view and a plan view of the ultrasonic transducer 3A according to the present embodiment, respectively.
In the drawings, the same members as those in the first and second embodiments are designated by the same reference numerals, and detailed description thereof will be omitted as appropriate.

The ultrasonic transducer 3A according to the present embodiment mainly has an elastic plate 310 and a plurality of piezoelectric elements 330 instead of the elastic plate 10 and the plurality of piezoelectric elements 30, and the tubular portion 42. It differs from the ultrasonic transducer 1A according to the first embodiment in that the filling portion 41, the closing portion 44, and the reinforcing plate 60 are deleted, and that the mass member 210 is provided. ..

The elastic plate 310 has a first surface 310a and a second surface 310b facing one side and the other side in the plate thickness direction, respectively, and is formed of a conductive metal plate that can vibrate in the plate thickness direction.

As shown in FIGS. 36 and 37, the elastic plates 310 are provided in parallel in the plate surface direction, and a plurality of vibration regions 312 in which the plurality of piezoelectric elements 330 are mounted, and the plurality of vibration regions 312 in a plan view. A plurality of low-rigidity regions 326 surrounding each of the vibration regions 312, a restraint region 314 surrounding each of the plurality of low-rigidity regions 326 in a plan view, and one restraint region 314 and the one restraint region 314 radially outward. It has a boundary region 316 that separates the outer region from which it is located.

Like the elastic plate 10, the elastic plate 310 has a base region 311 that surrounds the entire of the plurality of restraint regions 314.
Therefore, for one constrained region 314, the other confined region 314 and the adjacent base region 311 are the outer regions.

The boundary region 316 has the slit portion 17 and the bridge portion 18 like the boundary region 16.

The low-rigidity region 326 is a concave thin-walled region whose first surface is closer to the second surface than the first surface of the vibration region 312 and the restraint region 314 and which opens toward the first surface.

That is, the second surface 310b of the elastic plate 310 is flush with the vibration region 312, the low-rigidity region 326, and the restraint region 314, while the first surface 310a is the low-rigidity region 326. Is dented in.

The piezoelectric element 330 has an outer diameter larger than the vibration region 312 and smaller than the low rigidity region 326.
That is, the piezoelectric element 330 has a central portion 331 that overlaps with the vibration region 312 in a plan view, and an extending portion that extends radially outward from the central portion 331 and ends in the low rigidity region 326 in a plan view. It has 333 and.

As shown in FIG. 36, the lower surface electrode layer in the central portion 331 is fixed to the first surface of the vibration region 312 by the insulating adhesive 340, and the lower surface electrode layer in the extending portion is the conductive adhesive 345. Is electrically and mechanically connected to the first surface of the low rigidity region 326.

As shown in FIGS. 36 and 37, in the present embodiment, the piezoelectric element connection terminal corresponds to the state in which the insulating layer 82 of the flexible wiring board 80 is fixed to the upper surface of the mass member 210. A conductive adhesive or solder 87 is electrically and mechanically connected to the upper electrode layer of the piezoelectric element 330.
Therefore, also in the present embodiment, the flexible wiring board 80 can effectively prevent or reduce the deterioration of the vibration characteristics of the vibration region 312.

In the present embodiment, as shown in FIG. 37, the vibration region 312 has a circular shape in a plan view, the piezoelectric element 330 has a rectangular shape in a plan view, and the low rigidity region 326 has a rectangular shape in a plan view. However, as a matter of course, the present invention is not limited to such a shape.

That is, as long as the outer diameter of the piezoelectric element 330 is larger than the outer diameter of the vibration region 312 and smaller than the outer diameter of the low rigidity region 326, the vibration region 312, the piezoelectric element 330, and the low Various shapes are possible, such as making all of the rigid regions 326 a circular shape in a plan view.

Preferably, the low-rigidity region 326 has the same outer shape as the piezoelectric element 330 and has an outer diameter slightly larger than the outer diameter of the piezoelectric element 330.
According to such a configuration, the outer peripheral edge of the low rigidity region 326 can be used as an alignment mark when the piezoelectric element 330 is mounted on the vibration region 312.

As described above, in the present embodiment, the vibration region 312 and the central portion 331 of the piezoelectric element 330 are mechanically bonded by the insulating adhesive 340 to stabilize the support of the piezoelectric element 330. By connecting the low rigidity region 326 and the lower surface electrode layer of the extending portion 333 of the piezoelectric element 330 with a conductive adhesive 345, the lower surface electrode layer of the piezoelectric element 330 and the elastic plate 310 are electrically connected. Is getting.

Further, in the ultrasonic transducer 3A, as shown in FIG. 36, the bottom surface (first surface) of the thin-walled region forming the low-rigidity region 326 is lower than the first surface 310a of the vibration region 312. A raised portion 328 is provided, which is a raised portion 328 that cooperates with the inner surface of the thin-walled region to form an adhesive retention region.

The conductive adhesive 345 that electrically connects the lower surface electrode layer in the extending portion 333 and the first surface 310a of the low rigidity region 326 is provided in the adhesive retention region.

According to such a configuration, the insulating adhesive 340 that mechanically joins the central portion 331 of the piezoelectric element 330 and the vibration region 312, the lower electrode layer of the extending portion 333 of the piezoelectric element 330, and the low rigidity. It effectively prevents the conductive adhesive 345 that electrically connects the region 326 from being unexpectedly mixed and impairing the reliability of the electrical connection between the lower electrode layer of the piezoelectric element 330 and the elastic plate 310. can do.

In the present embodiment, as shown in FIGS. 36 and 37, the raised portions 328 are provided at two locations, but of course, the present invention is not limited to such a form. It is also possible to provide the raised portion 328 at only one location or at three or more locations.

The ultrasonic transducer 3A according to the present embodiment can be suitably manufactured by, for example, a manufacturing method with the following modifications as compared with the manufacturing method of the ultrasonic transducer 1A according to the first embodiment.

That is, in the manufacturing method of the present embodiment, the elastic plate etching step for forming the slit portion 17 half-etches the low-rigidity region 326 in addition to the full etching process for etching and removing the slit portion 17. It has a half-etching process (FIG. 38 (a)).

During the half-etching process, the region corresponding to the raised portion 328 is covered with a resist mask having a width slightly narrower than twice the amount of side etching. As a result, the raised portion 328 can be left so that the position of the top thereof is lower than the first surface 310a of the vibration region 312 and the restraint region 314, and contact with the lower surface of the piezoelectric element 330 can be prevented. it can.

Next, the conductive adhesive 328 is applied to the adhesive retention region, and the insulating adhesive 340 is applied to the vibration region 312 (FIG. 38 (b)), and after the piezoelectric element 330 is attached (FIG. 38 (FIG. 38)). c)), the conductive adhesive 328 and the insulating adhesive 340 are cured.

Reference numeral 346 in FIG. 36 indicates, in order to improve the reliability of the electrical connection between the conductive adhesive 345 and the elastic plate 310, before applying the conductive adhesive 345 to the adhesive retention region. Au plating is provided on the first surface of the adhesive retention region.

Various modifications can be made to the ultrasonic transducer according to the present embodiment.
39 and 40 show partial longitudinal sectional views of the ultrasonic transducers 3B and 3C according to the first and second modifications of the present embodiment, respectively.

As shown in FIG. 39, the first modification 3B further has the sound absorbing material 50 as compared with the present embodiment.
As shown in FIG. 40, the second modification 3C has the sound absorbing material 50, the filling portion 41, the tubular portion 42, the closing portion 44, and the reinforcing plate, as compared with the present embodiment. Has 60.

Embodiment 4
Hereinafter, the manufacturing method according to another embodiment of the present invention will be described with reference to the accompanying drawings.
FIG. 41 shows a longitudinal side view of the ultrasonic transducer 4A manufactured by the manufacturing method according to the present embodiment.
Further, FIGS. 42 and 43 show a cross-sectional plan view along the XXXXII-XXXXII line in FIG. 41 and an enlarged view of the XXXXIII part, respectively.
In the figure, the same members as those in the first to third embodiments are designated by the same reference numerals, and detailed description thereof will be omitted as appropriate.
In FIG. 42, the tubular portion and the sound absorbing material are not shown for the sake of comprehension.

The ultrasonic transducer 4A is different from the ultrasonic transducer 1A according to the first embodiment only in that the flexible wiring plate 80 is fixed to the first surface 10a of the elastic plate 10.

The manufacturing method according to the present embodiment has the same steps as the manufacturing method in the first embodiment up to the piezoelectric element mounting step (FIG. 10).

The manufacturing method according to the present embodiment includes a step of preparing the flexible wiring plate 80, a step of installing the protective member, and a step of installing the protective plate independently of the elastic plate forming step and the piezoelectric element mounting step. It has a step of mounting the flexible wiring board 80 before or after FIG. 11).

In the step of preparing the flexible wiring board 80, the sheet-shaped insulating layer forming member 182 forming the insulating layer 82 and the sheet-shaped conductor forming member 185 forming the wiring conductor 85 on the upper surface of the insulating layer forming member 182. It has a process (FIG. 44 (a)) of preparing a wiring sheet body 180 formed by laminating the above.

The insulating layer forming member 182 is, for example, a polyimide having a thickness of about 18 μm to 25 μm.
The conductor forming member 185 is, for example, Cu / Au having a thickness of about 12 μm to 18 μm.

The step of preparing the flexible wiring board 80 includes a process of etching and removing an unnecessary portion of the conductor forming member 185 to form the wiring conductor 85 having a predetermined shape (FIG. 44 (b)).

The manufacturing method further includes a process of removing unnecessary portions of the insulating layer forming member 182 by etching to form the insulating layer 82 having a predetermined shape (FIG. 44 (d)).

Also in the present embodiment, the flexible wiring board 80 has the insulating cover layer 83 that covers a predetermined portion of the wiring conductor 85.
Therefore, the step of preparing the flexible wiring board 80 is configured to include the installation process of the insulating cover layer 83.

The installation process of the insulating cover layer 83 can be performed, for example, before the insulating layer forming step (FIG. 44 (c)).
The insulating cover layer 83 can be formed by a photolithography technique using a photosensitive resin such as photosensitive polyimide.

The flexible wiring board mounting step includes an insulating layer fixing process (FIG. 45) in which the insulating layer 82 of the flexible wiring board 80 is fixed to a predetermined position on the first surface 10a of the elastic plate 10 with an adhesive, and a plurality of the insulating layer fixing treatments. It has an electrical connection process (FIGS. 46 and 47) in which the tip of the wiring conductor 85 is electrically connected to the upper surface electrode layer of the corresponding piezoelectric element 30 with a conductive adhesive or solder 87.

Here, in order to effectively prevent the conductive adhesive 87 from coming into contact with the elastic plate 10 and short-circuiting the upper surface electrode layer and the lower surface electrode layer, the manufacturing method according to the present embodiment is described. Prior to the electrical connection process, there is a process of applying an insulating adhesive 88 between the tip portions of the plurality of wiring conductors 85 and the corresponding piezoelectric element 30 (FIG. 47).

In this case, the conductive adhesive or the solder 87 in the electrical connection process has the insulating adhesive 88 interposed between the conductive adhesive or the solder 87 and the first surface 10a of the elastic plate 10. In the inserted state, the tips of the plurality of wiring conductors 85 are provided so as to be electrically connected to the upper surface electrode layer of the corresponding piezoelectric element 30.

The manufacturing method according to the present embodiment is the same as the manufacturing method in the first embodiment, after the protective member installation step and the protective plate installation step (see FIG. 11), the tubular portion installation step (FIG. 12). (See), the sound absorbing material installation step (see FIG. 15), the closing portion installation step (see FIG. 16), and the reinforcing plate installation step (see FIG. 42).

1A to 1I, 2A to 2C, 3A to 3C, 4A Ultrasonic transducers 10, 310 Elastic plates 10a, 310a First surface 10b, 310b Second surface 11, 311 Base area 12, 312 Vibration area 14, 314 Restraint area 16 316 Boundary area 17 Slit part 17a, 17b First and second plate surface direction slit 18 Bridge part 26, 326 Low rigidity area 27 Groove 28a Opening part 28b Connecting part 30, 330 Conductive element 40 Encapsulating member 41 Filling part 42 Cylinder Shape 44 Closure 50 Sound absorbing material 60, 260 Rigid reinforcement plate 70 Protective member 72 Opening 75, 175, 275 Protective plate 77, 177 Through hole 80 Wiring body 82 Insulating layer 83 Insulating cover layer 85 Wiring conductor 87 Conductive adhesive Or solder 88 Insulating adhesive 110 Elastic plate forming body 180 Wiring sheet body 182 Insulating layer forming member 185 Wiring conductor forming member 210 Mass member 210a Mass member for restraint region 210b Mass member for base region 215 Bridge between restraint regions 216 Restraint region / Bridge between base regions 250 Spacer 328 Raised part 331 Central part 333 Extended part 340 Insulating adhesive 345 Conductive adhesive

In order to achieve the second object, the present invention has a first surface and a second surface facing one side and the other side in the plate thickness direction, respectively, and can vibrate in the plate thickness direction. A plurality of piezoelectric elements fixed in parallel to the first surface of the plate, a sealing member having a plurality of tubular portions surrounding each of the plurality of piezoelectric elements in a plan view, and a flexible wiring plate are provided. The elastic plate surrounds a plurality of vibration regions in which the plurality of piezoelectric elements are mounted, a plurality of low-rigidity regions surrounding the plurality of vibration regions in a plan view, and a plurality of low-rigidity regions in a plan view. The low-rigidity region includes a plurality of restraint regions and a boundary region that partitions one restraint region and an outer region located radially outward from the one restraint region, and the low-rigidity region is radially inward of the region. The rigidity is lower than that of the vibration region located in and the restraint region located outside the radial direction of the region, and the boundary region includes a slit portion that divides one restraint region and the outer region. The flexible wiring plate has an insulating layer fixed to the upper surface of the tubular portion and an insulating layer fixed to the upper surface of the insulating layer. The wiring conductor is a method for manufacturing an ultrasonic transducer having a plurality of tip regions electrically connected to the upper surface electrode layers of the plurality of piezoelectric elements. An elastic plate forming step of etching a conductive elastic plate forming body to form the elastic plate, and conductively adhering the lower surface electrode layers of the plurality of piezoelectric elements to the first surfaces of the plurality of vibration regions. A piezoelectric element mounting step of bonding with an agent, a tubular portion installation step of installing the plurality of tubular portions so as to surround each of the plurality of low-rigidity regions in a plan view, and a wiring conductor provided on the upper surface of the insulating layer. A flexible wiring plate formed of a flexible wiring plate, wherein the wiring conductor has a main body region located on the insulating layer and a plurality of tip regions extending from the main body region so as to extend outward from the insulating layer. The step of preparing the flexible wiring plate to be provided, the insulating layer is fixed to the upper surface of the tubular portion with an adhesive, and the connection terminals for the piezoelectric elements in the plurality of tip regions are connected to the upper surface electrodes of the plurality of piezoelectric elements. The step of preparing the flexible wiring board includes a flexible wiring board mounting step of electrically connecting the layers with a conductive adhesive or solder, respectively, and the step of preparing the flexible wiring board is at least a stage before the flexible wiring board mounting step of the elastic plate. Forming step, said piezoelectric element mounting step And a first method of manufacturing an ultrasonic transducer, which is performed independently of the tubular portion installation step.

Claims (42)

An elastic plate having a first surface and a second surface facing one side and the other side in the plate thickness direction and vibrating in the plate thickness direction, and a plurality of piezoelectric plates fixed in parallel to the first surface of the elastic plate. The element, a sealing member having a plurality of tubular portions surrounding each of the plurality of piezoelectric elements in a plan view, and a flexible wiring plate are provided.
The elastic plate has a plurality of vibration regions to which the plurality of piezoelectric elements are mounted, a plurality of low-rigidity regions surrounding the plurality of vibration regions in a plan view, and the plurality of low-rigidity regions in a plan view. Includes a plurality of surrounding constrained regions and a boundary region that separates one constrained region and an outer region located radially outward from the one constrained region.
The low-rigidity region has a lower rigidity than the vibration region located inward in the radial direction of the region and the restraint region located in the radial outer direction of the region.
The boundary region has a slit portion that divides one restraint region and an outer region, and a bridge portion that mechanically connects one restraint region to the outer region.
The plurality of tubular portions are arranged so as to surround the plurality of low-rigidity regions in a plan view.
The flexible wiring board has an insulating layer fixed to the upper surface of the tubular portion and a wiring conductor provided on the upper surface of the insulating layer, and the wiring conductor is an upper surface electrode layer of the plurality of piezoelectric elements. An ultrasonic transducer characterized by having multiple tip regions, each electrically connected to a. The wiring conductor has a main body region located on the insulating layer and a plurality of tip regions extending outward from the main body region so as to extend outward from the insulating layer.
The tip region is characterized by having a connection terminal for a piezoelectric element that is electrically connected by a conductive adhesive or solder in a state of being polymerized on the upper surface electrode layer of the corresponding piezoelectric element in a plan view. The ultrasonic transducer according to claim 1. The piezoelectric element is configured such that the upper surface of the upper surface electrode layer is located at the first height with respect to the first surface of the elastic plate, and the upper surface of the tubular portion is based on the first surface of the elastic plate. It is configured to be located at the second height, which is higher than the first height.
The tip region is configured such that the connection terminal for the piezoelectric element is located at a third height lower than the second height and at least the first height with respect to the first surface of the elastic plate. The ultrasonic transducer according to claim 2. The tubular portion is arranged so that the base end surface straddles the slit portion.
The sealing member according to any one of claims 1 to 3, wherein the sealing member has, in addition to the tubular portion, a filling portion extending from the base end surface of the tubular portion to the inside of the slit portion. The described ultrasonic transducer. The ultrasonic transducer according to claim 4, wherein the sealing member further has a closing portion that closes each of the free end sides of the plurality of tubular portions. The tubular portion and the filling portion are integrally formed of the first polymer material, and the closed portion is formed of the second polymer material.
The ultrasonic transducer according to claim 5, wherein the first polymer material has a viscosity lower than that of the second polymer material based on a state before curing. The ultrasonic transducer according to claim 5 or 6, wherein a rigid reinforcing plate is fixed to the outer surface of the closed portion. The ultrasonic transducer according to claim 7, wherein a protective member having an opening that opens the vibration region to the outside is fixed to the second surface of the elastic plate. The ultrasonic transducer according to claim 8, wherein a rigid protective plate provided with a through hole at a position corresponding to the opening is fixed to the outer surface of the protective member. A protective member fixed to the second surface of the elastic plate and provided with an opening for opening the vibration region to the outside, and a protective member.
A rigid protective plate provided on the outer surface of the protective member, and a protective plate provided with a through hole at a position corresponding to the opening of the protective member.
A rigid reinforcing plate provided on the outer surface of the closed portion is provided.
The protective plate has a central portion fixed to the outer surface of the protective member and an extending portion extending outward in the plate surface direction from the central portion.
The reinforcing plate has a central portion fixed to the outer surface of the closed portion and an extending portion extending outward in the plate surface direction from the central portion.
The ultrasonic transducer according to claim 5 or 6, wherein the extending portion of the reinforcing plate and the extending portion of the protective plate are connected via a spacer. A protective member fixed to the second surface of the elastic plate and provided with an opening for opening the vibration region to the outside, and a protective member.
From the end wall portion extending along the outer surface of the protective member and having a through hole provided at a position corresponding to the opening of the protective member, and surrounding the outer periphery of the protective member and the elastic plate. A protective container including an extending peripheral wall and
The fifth or sixth aspect of claim 5 or 6, wherein a reinforcing plate connected to the peripheral wall portion is provided so as to close the free end opening of the peripheral wall portion of the protective container while covering the outer surface of the closed portion. Ultrasonic transducer. The first to eleventh aspects of claims 1 to 11, wherein a sound absorbing material made of a foamable resin is provided so as to surround the piezoelectric element in the accommodation space of the piezoelectric element surrounded by the tubular portion in a plan view. The ultrasonic transducer according to any one. A mass member fixed to the first surface of the restraint region so as to open the first surface of the vibration region, the low rigidity region, and the boundary region is provided.
The tubular portion is arranged so that the base end surface straddles the slit portion.
The ultrasonic transducer according to any one of claims 1 to 11, wherein the insulating layer of the flexible wiring board is fixed to the upper surface of the mass member in addition to the upper surface of the tubular portion. The super-superimposition according to claim 13, wherein a sound absorbing material made of a foamable resin is provided so as to surround the piezoelectric element in the accommodating space of the piezoelectric element surrounded by the mass member in a plan view. Ultrasonic transducer. An elastic plate having a first surface and a second surface facing one side and the other side in the plate thickness direction and vibrating in the plate thickness direction, and a plurality of piezoelectric plates fixed in parallel to the first surface of the elastic plate. The element, the mass member fixed to the first surface of the elastic plate, and the flexible wiring plate are provided.
The elastic plate has a plurality of vibration regions to which the plurality of piezoelectric elements are mounted, a plurality of low-rigidity regions surrounding the plurality of vibration regions in a plan view, and the plurality of low-rigidity regions in a plan view. Includes a plurality of surrounding constrained regions and a boundary region that separates one constrained region and an outer region located radially outward from the one constrained region.
The low-rigidity region has a lower rigidity than the vibration region located inward in the radial direction of the region and the restraint region located in the radial outer direction of the region.
The boundary region has a slit portion that divides one restraint region and an outer region, and a bridge portion that mechanically connects one restraint region to the outer region.
The mass member is fixed to the first surface of the restraint region so as to surround the low rigidity region in a plan view while opening the first surfaces of the vibration region, the low rigidity region, and the boundary region.
The flexible wiring board has an insulating layer fixed to the upper surface of the mass member and a wiring conductor provided on the upper surface of the insulating layer, and the wiring conductor is formed on the upper surface electrode layers of the plurality of piezoelectric elements. An ultrasonic transducer, each of which has a plurality of electrically connected tip regions. The ultrasonic according to claim 15, wherein a sound absorbing material made of a foamable resin is provided so as to surround the piezoelectric element in the accommodating space of the piezoelectric element surrounded by the mass member in a plan view. Ultrasonic transducer. The mass member has a plurality of mass members for restraint regions fixed to the first surfaces of the plurality of restraint regions so as to surround the plurality of low-rigidity regions in a plan view.
The ultrasonic transducer further closes a plurality of tubular portions provided in the boundary region and the free end sides of the plurality of tubular portions so as to surround the plurality of restraint region mass members in a plan view. The ultrasonic transducer according to claim 15 or 16, further comprising a sealing member including the closing portion and a rigid reinforcing plate fixed to the outer surface of the closing portion. The ultrasonic transducer according to claim 17, wherein a protective member having an opening that opens the vibration region to the outside is fixed to the second surface of the elastic plate. The ultrasonic transducer according to claim 18, wherein a rigid protective plate provided with a through hole at a position corresponding to the opening is fixed to the outer surface of the protective member. The mass member has a plurality of mass members for restraint regions fixed to the first surfaces of the plurality of restraint regions so as to surround the plurality of low-rigidity regions in a plan view.
The ultrasonic transducer further closes a plurality of tubular portions provided in the boundary region and the free end sides of the plurality of tubular portions so as to surround the plurality of restraint region mass members in a plan view. And the sealing member including the closing part
A protective member fixed to the second surface of the elastic plate and provided with an opening for opening the vibration region to the outside, and a protective member.
A rigid protective plate provided on the outer surface of the protective member, and a protective plate provided with a through hole at a position corresponding to the opening of the protective member.
A rigid reinforcing plate provided on the outer surface of the closed portion is provided.
The protective plate has a central portion fixed to the outer surface of the protective member and an extending portion extending outward in the plate surface direction from the central portion.
The reinforcing plate has a central portion fixed to the outer surface of the closed portion and an extending portion extending outward in the plate surface direction from the central portion.
The ultrasonic transducer according to claim 15 or 16, wherein the extending portion of the reinforcing plate and the extending portion of the protective plate are connected via a spacer. The mass member has a plurality of mass members for restraint regions fixed to the first surfaces of the plurality of restraint regions so as to surround the plurality of low-rigidity regions in a plan view.
The ultrasonic transducer further closes a plurality of tubular portions provided in the boundary region and the free end sides of the plurality of tubular portions so as to surround the plurality of restraint region mass members in a plan view. And the sealing member including the closing part
A protective member fixed to the second surface of the elastic plate and provided with an opening for opening the vibration region to the outside, and a protective member.
From the end wall portion extending along the outer surface of the protective member and having a through hole provided at a position corresponding to the opening of the protective member, and surrounding the outer periphery of the protective member and the elastic plate. A protective container including an extending peripheral wall and
The 15th or 16th claim, wherein the protective container is provided with a reinforcing plate connected to the peripheral wall portion so as to close the free end opening of the peripheral wall portion while covering the outer surface of the closed portion. Ultrasonic transducer. The ultrasonic transducer according to any one of claims 1 to 21, wherein the low-rigidity region has a groove that opens on the first surface of the elastic plate. The low-rigidity region includes an opening that divides the vibration region and the restraint region, and a connecting portion that connects the vibration region and the restraint region, and the opening and the connecting portion are the vibration. The ultrasonic transducer according to any one of claims 1 to 21, wherein the ultrasonic transducers are provided alternately along the outer peripheral edge of the region. The low-rigidity region is a concave thin-walled region in which the first surface is closer to the second surface than the first surface of the vibration region and the restraint region.
The piezoelectric element includes a central portion that overlaps with the vibration region in a plan view, and an extending portion that extends radially outward from the central portion and ends in the low rigidity region in a plan view.
The lower surface electrode layer in the central portion is fixed to the first surface of the vibration region by an insulating adhesive, and the lower surface electrode layer in the extending portion is electrically connected to the first surface of the low rigidity region by the conductive adhesive. The ultrasonic transducer according to any one of claims 1 to 21, wherein the ultrasonic transducer is physically and mechanically connected. The bottom surface of the thin-walled region is provided with a raised portion that is lower than the first surface of the vibration region and that cooperates with the inner surface of the thin-walled region to form an adhesive retention region.
A claim characterized in that the conductive adhesive that electrically and mechanically connects the lower surface electrode layer in the extending portion and the first surface of the low rigidity region is provided in the adhesive retention region. Item 24. The ultrasonic transducer. In the plurality of restraint regions, a group of restraint regions formed by m (m is an integer of 1 or more) arranged along the first plate surface direction of the elastic plate is orthogonal to the first plate surface direction. It has n rows (n is an integer of 1 or more) in the direction of the second plate surface, and has m × n restraint regions that appear by being provided.
The slit portions are located on both sides of the one piezoelectric element mounted in the vibration region in the one restraint region in the direction of the second plate surface, and are paired in the direction of the first plate surface extending along the direction of the first plate surface. Includes a slit and a pair of second plate surface direction slits located on both sides of the one piezoelectric element in the first plate surface direction and extending along the second plate surface direction.
The pair of slits in the direction of the first plate surface is longer than the length of the one piezoelectric element in the direction of the first plate surface, and the pair of slits in the direction of the second plate surface is longer than the length of the pair of piezoelectric elements in the direction of the second plate surface. Being long
From claim 1, the bridge portion is formed by four locations defined between the ends of the first plate surface direction slit and the second plate surface direction slit adjacent to each other in the circumferential direction. 25. The ultrasonic transducer according to any one of 25. 26. Claim 26, wherein a single common slit is provided between adjacent constrained regions, and the single common slit demarcates the outer peripheral edges of both adjacent constrained regions. Ultrasonic transducer. An elastic plate that has a first surface and a second surface facing one side and the other side in the plate thickness direction and can vibrate in the plate thickness direction, and a plurality of piezoelectric plates fixed in parallel to the first surface of the elastic plate. A plurality of elements, a sealing member having a plurality of tubular portions surrounding each of the plurality of piezoelectric elements in a plan view, and a flexible wiring plate are provided, and the elastic plate is mounted with the plurality of piezoelectric elements. Vibration region, a plurality of low-rigidity regions surrounding the plurality of vibration regions in a plan view, a plurality of constraint regions surrounding the plurality of low-rigidity regions in a plan view, one constraint region and the one constraint. The low-rigidity region includes the boundary region that partitions the outer region located radially outward from the region, and the low-rigidity region extends radially inward and radially outward of the region. The rigidity is lower than that of the constrained region where it is located, and the boundary region is a slit portion that divides one restraint region and an outer region, and a bridge portion that mechanically connects one restraint region to the outer region. The flexible wiring plate has an insulating layer fixed to the upper surface of the tubular portion and a wiring conductor provided on the upper surface of the insulating layer, and the wiring conductors include a plurality of the wiring conductors. This is a method for manufacturing an ultrasonic transducer having a plurality of tip regions electrically connected to the upper surface electrode layer of the piezoelectric element of the above.
An elastic plate forming step of forming the elastic plate by etching a conductive elastic plate forming body, and
A piezoelectric element mounting step of adhering the lower surface electrode layers of the plurality of piezoelectric elements to the first surface of the plurality of vibration regions with a conductive adhesive, respectively.
A tubular portion installation step of installing the plurality of tubular portions so as to surround each of the plurality of low-rigidity regions in a plan view,
A flexible wiring board in which a wiring conductor is provided on the upper surface of the insulating layer, the wiring conductor extends from the main body region located on the insulating layer and outward from the insulating layer. The process of preparing a flexible wiring board having a plurality of existing tip regions, and
The insulating layer is fixed to the upper surface of the tubular portion with an adhesive, and the connection terminals for the piezoelectric elements in the plurality of tip regions are electrically attached to the upper surface electrode layers of the plurality of piezoelectric elements by a conductive adhesive or solder, respectively. Including the flexible wiring board mounting process to connect
The step of preparing the flexible wiring board is executed independently of the elastic plate forming step, the piezoelectric element mounting step, and the sealing member installation step at least in a stage prior to the flexible wiring board mounting step. A method for manufacturing an ultrasonic transducer. Prior to the tubular portion installation step, a protective member provided with an opening for opening the vibration region to the outside is provided with a second surface of the slit portion while opening the vibration region to the outside through the opening. A protective member installation step of fixing to the second surface of the elastic plate so as to close the side is provided.
In the tubular portion installation step, the elastic plate is provided so that the sealing member integrally has a filling portion extending from the base end surface of the tubular portion to the inside of the slit portion in addition to the tubular portion. A process of applying a first polymer material to a tubular portion installation region surrounding the low-rigidity region in a plan view on the inside of the slit portion and the first surface of the elastic plate from the side of one surface and curing the first polymer material is included. 28. The method for manufacturing an ultrasonic transducer according to claim 28. In the elastic plate forming step, the elastic plate is formed so that the elastic plate has a base region that surrounds the entire of the plurality of restraint regions in a plan view.
After the piezoelectric element mounting step, a process of fixing a plurality of mass members for restraint regions to the first surfaces of the plurality of restraint regions so as to surround the plurality of low rigidity regions in a plan view, and a base to the base region. The method for manufacturing an ultrasonic transducer according to claim 28 or 29, wherein the mass member installation step including a process of fixing the mass member for a region is provided. The process of preparing the flexible wiring board is
A process of preparing a sheet-shaped insulating layer forming member forming the insulating layer and a wiring sheet body in which the sheet-shaped conductor forming member forming the wiring conductor is laminated on the upper surface of the insulating layer forming member.
A process of forming the wiring conductor having a predetermined shape by etching and removing an unnecessary portion of the conductor forming member.
It is characterized by having a process of forming the insulating layer having a predetermined shape by etching and removing unnecessary portions of the insulating layer forming member so that the wiring conductor has the main body region and the plurality of tip regions. The method for manufacturing an ultrasonic transducer according to any one of claims 28 to 30. In the tubular portion installation step, the upper surface of the plurality of tubular portions is higher than the first height of the upper surface of the upper surface electrode layer of the piezoelectric element with reference to the first surface of the elastic plate. The plurality of tubular parts are to be installed so as to be located in.
In the step of preparing the flexible wiring board, after the process of forming the insulating layer, the tip portions in the plurality of tip regions correspond to the upper surface of the piezoelectric element in a plan view when the flexible wiring board is mounted. The tip region is formed so as to polymerize with the electrode layer and to be located at a third height equal to or higher than the first height so that the height with respect to the first surface of the elastic plate is lower than the second height. The method for manufacturing an ultrasonic transducer according to claim 31, further comprising a process of bending. An elastic plate having a first surface and a second surface facing one side and the other side in the plate thickness direction and vibrating in the plate thickness direction, and a plurality of piezoelectric plates fixed in parallel to the first surface of the elastic plate. The element, a mass member fixed to the first surface of the elastic plate, a sealing member having a plurality of tubular portions surrounding each of the plurality of piezoelectric elements in a plan view, and a flexible wiring plate are provided. The elastic plate surrounds a plurality of vibration regions to which the plurality of piezoelectric elements are mounted, a plurality of low-rigidity regions surrounding the plurality of vibration regions in a plan view, and a plurality of low-rigidity regions in a plan view. It is located between a plurality of constrained regions, a base region that surrounds the entire of the plurality of constrained regions in a plan view, one adjacent constrained region and another constrained region, and between adjacent constrained regions and the base region. The low-rigidity region includes a boundary region that demarcates the boundary of each of the plurality of restraint regions, and the low-rigidity region includes the vibration region located inward in the radial direction of the region and the restraint region located outside in the radial direction of the region. The boundary region has a slit portion that separates the one restraint region from the surroundings and a bridge portion that mechanically connects the one restraint region to the surroundings, and has the mass. The member includes a plurality of restraint region mass members fixed to the plurality of restraint regions, and a base region mass member fixed to the base region, and the flexible wiring plate is the restraint region mass member. It has an insulating layer fixed to the upper surface of the insulating layer and a wiring conductor provided on the upper surface of the insulating layer, and the wiring conductor is a plurality of electrically connected to the upper surface electrode layers of the plurality of piezoelectric elements. A method for manufacturing an ultrasonic transducer having a tip region.
An elastic plate forming step of forming the elastic plate by etching a conductive elastic plate forming body, and
A piezoelectric element mounting step of adhering the lower surface electrode layers of the plurality of piezoelectric elements to the first surface of the plurality of vibration regions with a conductive adhesive, respectively.
A mass member installation step including a process of fixing the mass member for the restraint region to each of the plurality of restraint regions and a process of fixing the mass member for the base region to the base region.
A flexible wiring board in which a wiring conductor is provided on the upper surface of the insulating layer, the wiring conductor extends from the main body region located on the insulating layer and outward from the insulating layer. The process of preparing a flexible wiring board having a plurality of existing tip regions, and
The insulating layer is fixed to the upper surface of the mass member for the restraint region with an adhesive, and the connection terminals for the piezoelectric elements in the plurality of tip regions are electrically connected to the upper surface electrode layers of the plurality of piezoelectric elements by a conductive adhesive or solder, respectively. Including the flexible wiring board mounting process to connect
The step of preparing the flexible wiring board is to be executed independently of the elastic plate forming step, the piezoelectric element mounting step, and the mass member installation step at least in a stage prior to the flexible wiring board mounting step. A method for manufacturing an ultrasonic transducer as a feature. The process of preparing the flexible wiring board is
A process of preparing a sheet-shaped insulating layer forming member forming the insulating layer and a wiring sheet body in which the sheet-shaped conductor forming member forming the wiring conductor is laminated on the upper surface of the insulating layer forming member.
A process of forming the wiring conductor having a predetermined shape by etching and removing an unnecessary portion of the conductor forming member.
The wiring conductor is characterized by having a process of etching and removing unnecessary portions of the insulating layer forming member to form the insulating layer having a predetermined shape so that the wiring conductor has the main body region and the plurality of tip regions. 33. The method for manufacturing an ultrasonic transducer according to claim 33. In the mass member installation step, the upper surface of the mass member for the restraint region is set to a second height higher than the first height of the upper surface of the upper surface electrode layer of the piezoelectric element, with reference to the first surface of the elastic plate. The mass member for the restraint region is to be installed so as to be located.
In the step of preparing the flexible wiring board, after the process of forming the insulating layer, the tip portions in the plurality of tip regions correspond to the upper surface of the piezoelectric element in a plan view when the flexible wiring board is mounted. The tip region is formed so as to polymerize with the electrode layer and to be located at a third height equal to or higher than the first height so that the height with respect to the first surface of the elastic plate is lower than the second height. The method for manufacturing an ultrasonic transducer according to claim 34, which comprises a process of bending. In the mass member installation step, the restraint connecting the upper ends of the plurality of restraint region mass members, the base region mass member, one adjacent restraint region mass member, and another restraint region mass member. A process of preparing a mass plate including an inter-regional bridge and a constraining region / base region inter-region bridge connecting the upper ends of adjacent restraint region mass members and base region mass members, and the mass plate being used as the elastic plate. The process of fixing to a predetermined position on the first surface of the above and cutting the bridge between the restraint regions and the bridge between the restraint regions and the base region to separate the plurality of mass members for the restraint region and the mass member for the base region. The method for manufacturing an ultrasonic transducer according to any one of claims 33 to 35, which comprises a process. The process of preparing the mass plate is a process of preparing a plate-shaped metal block having a thickness corresponding to the height of the mass member for the restraint region and the mass member for the base region, and a process of preparing the plate-shaped metal block from one surface of the metal block. The method for manufacturing an ultrasonic transducer according to claim 36, which includes a process of half-etching a region corresponding to the restraint region-to-base region bridge and the restraint region / base region-to-base region bridge. In the step of preparing the flexible wiring board, after the process of forming the wiring conductor, a process of installing an insulating cover layer so as to cover at least a part of the region forming the main body region of the wiring conductor is performed. The method for manufacturing an ultrasonic transducer according to any one of claims 28 to 37, wherein the ultrasonic transducer is provided. The low-rigidity region is a groove opened on the side of the first surface provided along the outer peripheral edge of the vibration region, or a plurality of openings provided along the outer peripheral edge of the vibration region. It is said that there are multiple openings with a connecting part left between the openings adjacent in the circumferential direction.
The elastic plate forming step according to any one of claims 28 to 38, wherein the elastic plate forming step is configured to form the slit portion and the groove or the plurality of openings in the low rigidity region by etching. The method for manufacturing an ultrasonic transducer according to the description. The low-rigidity region is a concave thin-walled region that opens toward the first surface side, in which the first surface of the low-rigidity region is closer to the second surface than the first surface of the vibration region and the restraint region. ,
On the bottom surface of the thin-walled region, a raised portion which is lower than the first surface of the vibration region and the restraint region and cooperates with the inner surface of the thin-walled region to form an adhesive retention region is provided. Be,
The piezoelectric element polymerizes with the vibration region in a plan view, has a central portion joined to the first surface of the vibration region by an insulating adhesive, and extends radially outward from the center portion and is described in a plan view. It has an extending portion that ends in the low-rigidity region and is joined to the first surface of the low-rigidity region by a conductive adhesive disposed in the adhesive retention region.
The etching in the elastic plate forming step is a concave thin-walled region obtained by performing a full etching process for forming the slit portion and half-etching from the side of the first surface with respect to the region corresponding to the low-rigidity region. Including half-etching to form a low-rigidity region
In the half-etching process, the region corresponding to the vibration region and the region corresponding to the restraint region are covered with a mask, and the region corresponding to the raised portion is covered with a mask having a width narrower than twice the amount of side etching. It is configured to leave the vibration region and the raised portion lower than the restraint region on the bottom surface of the concave thin-walled region while making the low-rigidity region a concave thin-walled region that opens to the first surface side. The method for manufacturing an ultrasonic transducer according to any one of claims 28 to 39. An elastic plate having a first surface and a second surface facing one side and the other side in the plate thickness direction and vibrating in the plate thickness direction, and a plurality of piezoelectric plates fixed in parallel to the first surface of the elastic plate. The elastic plate includes an element and a flexible wiring plate fixed to the first surface of the elastic plate, and the elastic plate includes a plurality of vibration regions in which the plurality of piezoelectric elements are mounted, and the plurality of vibration regions in a plan view. A plurality of low-rigidity regions surrounding each of the two low-rigidity regions, a plurality of restraint regions surrounding the plurality of low-rigidity regions in a plan view, one restraint region, and an outer region located radially outward from the one restraint region. The low-rigidity region includes the boundary region for partitioning the region, and the low-rigidity region has lower rigidity than the vibration region located inward in the radial direction of the region and the restraint region located in the radial outer direction of the region. The boundary region is an ultrasonic transformer having a slit portion that divides the one restraint region and the outer region, and a bridge portion that mechanically connects the one restraint region to the outer region. It ’s a method of manufacturing a ductor.
An elastic plate forming step of forming the elastic plate by etching a conductive elastic plate forming body, and
A piezoelectric element mounting step of adhering the lower surface electrode layers of the plurality of piezoelectric elements to the first surface of the plurality of vibration regions with a conductive adhesive, respectively.
The process of preparing a flexible wiring board in which a wiring conductor is provided on the upper surface of the insulating layer, and
An insulating layer fixing process for fixing the insulating layer to a predetermined position on the first surface of the elastic plate with an adhesive, and a conductive adhesive or solder to the upper surface electrode layer of the piezoelectric element corresponding to the tips of the plurality of wiring conductors. Has a flexible wiring board mounting process that includes electrical connection processing that is electrically connected by
A method for manufacturing an ultrasonic transducer, wherein the step of preparing the flexible wiring board is executed independently of the step of forming the elastic plate and the step of mounting the piezoelectric element. The flexible wiring board mounting step includes an insulating resin installation process for applying an insulating resin between the tips of the plurality of wiring conductors and the corresponding piezoelectric elements before the electrical connection process.
The conductive adhesive or the solder in the electrical connection process is a plurality of the conductive adhesive or the solder in a state where the insulating resin is interposed between the conductive adhesive or the solder and the first surface of the elastic plate. The method for manufacturing an ultrasonic transducer according to claim 41, wherein the tip end portion of the wiring conductor is electrically connected to the upper surface electrode layer of the corresponding piezoelectric element.

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