JP6598417B1 - Ultrasonic transducer and manufacturing method thereof - Google Patents

Abstract

An ultrasonic transducer according to the present invention surrounds an elastic plate that can vibrate in the thickness direction, a plurality of piezoelectric elements that are fixed in parallel to the first surface of the elastic plate, and a plurality of piezoelectric elements in plan view. A plurality of cylindrical portions, and a flexible wiring board, wherein the elastic plate includes a plurality of vibration regions to which the plurality of piezoelectric elements are respectively attached, a plurality of low-rigid regions that respectively surround the plurality of vibration regions, and a plurality of A plurality of constraining regions that respectively surround the low-rigidity region, and a boundary region that divides one constraining region and an outer region located radially outward from the one constraining region, A slit portion that divides one constraining region and the outer region, and a bridge portion that mechanically connects the one constraining region to the outer region. The flexible wiring board has an insulating layer fixed to the upper surface of the cylindrical 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. And a plurality of tip regions electrically connected to each other.

Description

  The present invention relates to an ultrasonic transducer that includes a plurality of piezoelectric elements arranged in parallel and can be suitably used as a phased array sensor, and a manufacturing method thereof.

  An ultrasonic transducer in which a plurality of vibrators 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. In this case, the following items are required for the ultrasonic transducer.

  That is, in order to suppress the occurrence of the grating lobe phenomenon between the plurality of vibrators, the arrangement pitch of the plurality of vibrators needs to be ½ or less of the wavelength λ of the ultrasonic wave emitted by the vibrators. There is.

  On the other hand, in order to detect an object several meters ahead, it is necessary to set the frequency of the ultrasonic wave radiated by the vibrator used for 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 vibrator to 40 kHz, the arrangement pitch of the plurality of vibrators is set. It is necessary to make 8.6 mm / 2 = 4.3 mm or less.

  However, at present, the diameter of a vibrating body capable of emitting ultrasonic waves of 40 kHz is about 10 mm, and therefore, it is impossible to satisfy the above-described demand 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 radiates 40 kHz ultrasonic waves has been proposed.

  In the first conventional configuration, one end side opening of a waveguide is connected to each of a plurality of vibrators arranged in parallel, and the vibration body radiates the arrangement pitch of the other end side opening of the waveguide. It is comprised so that it may be set to 1/2 or less of the wavelength of an ultrasonic wave.

However, the first conventional configuration has a problem that the entire size of the sensor including the waveguide is increased.
Another problem is that reflection of ultrasonic waves generated in the waveguide adversely affects the ultrasonic radiation profile.

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

  In the second conventional configuration, the size of the diaphragm oscillated by the piezoelectric element can be 400 to 800 μm, and a plurality of vibrators 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 ultrasonic waves with a low frequency of about 40 kHz necessary for detecting an object several meters ahead.
Moreover, the problem that manufacturing cost rises with the complexity of a manufacturing process also arises.

JP 2010-164331 A JP 2013-046086 A

The present invention has been made in view of such a conventional technique, and is an ultrasonic transducer including a plurality of piezoelectric elements arranged in parallel, and an array of a plurality of vibrating bodies formed by the plurality of piezoelectric elements, respectively. While narrowing the pitch, it is possible to prevent the propagation of vibration between the plurality of vibrating bodies as much as possible. Further, it is effective that the voltage supply path to 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.
In addition, 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, according to a first aspect of the present invention, there is provided an elastic plate having a first surface and a second surface facing the one side and the other side in the plate thickness direction and capable of 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 cylindrical portions surrounding each of the plurality of piezoelectric elements in plan view, a flexible wiring board, The elastic plate includes a plurality of vibration regions to which the plurality of piezoelectric elements are respectively attached, a plurality of low rigidity regions surrounding the plurality of vibration regions in plan view, and the plurality of low stiffnesses in plan view. A plurality of constraining regions each surrounding the region, and a boundary region that divides one constraining region and an outer region located radially outward from the one constraining region, and the low-rigidity region includes The vibration region and the radially inner portion The rigidity of the region is lower than that of the constraining region located radially outward of the region, the boundary region includes a slit part that divides the constraining region and the outward region, and the constraining region is defined as the outer region. And the plurality of cylindrical portions are arranged so as to surround the plurality of low-rigidity regions in a plan view, and the flexible wiring board is formed of the cylindrical portion. An insulating layer fixed to the upper surface; and a wiring conductor provided on the upper surface of the insulating layer, wherein the wiring conductor is electrically connected to the upper surface electrode layers of the plurality of piezoelectric elements. An ultrasonic transducer having a region is provided.

With the ultrasonic transducer according to the first 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, it is possible to effectively radiate low-frequency ultrasonic waves while effectively preventing or reducing mutual interference between the plurality of piezoelectric elements.

  Furthermore, in the ultrasonic transducer, the vibration region is flexibly supported through the low-rigidity region, and a low resonance frequency can be realized even if the area of the vibration region is reduced. The sound pressure can be increased.

  In the ultrasonic transducer, since the flexible wiring board is not directly fixed to the elastic plate, but is fixed to the upper surface of the cylindrical portion, the flexible wiring board includes the plurality of vibrating bodies. It is possible to effectively prevent or reduce the influence on the vibration characteristics.

In one form, the said wiring conductor may have a main body area | region located on the said insulating layer, and the said some front end area | region extended from the said main body area | region so that it might extend outward from the said 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 corresponding upper surface electrode layer of the piezoelectric element in plan view.

  The piezoelectric element is configured such that the upper surface of the upper electrode layer is positioned at a first height with respect to the first surface of the elastic plate, and the upper surface of the cylindrical portion is based on the first surface of the elastic plate. The tip region has a second height on the basis of the first surface of the elastic plate. It is comprised so that it may be located in the 3rd height below the height and 1st height or more.

  In the various configurations, the cylindrical portion is disposed such that a base end surface straddles the slit portion, and the sealing member is formed from the base end surface of the cylindrical portion to the slit portion in addition to the cylindrical portion. May have a filling portion extending into the interior of the.

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

  The sealing member may further include a closing portion that closes the free end sides of the plurality of cylindrical portions.

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

  Preferably, the cylindrical portion and the filling portion are integrally formed of a first polymer material, the closing portion is formed of a second polymer material, and the first polymer material is based on a state before curing. Thus, the viscosity is lower than that of the second polymer material.

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

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

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

  According to such a configuration, external contact 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, it is possible to effectively prevent damage to the surface of the protective member and to suppress vibration of the surface of the protective member.

Instead of the protective plate and the reinforcing plate, a rigid protective plate provided on the outer surface of the protective member, 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 an extending portion extending outward in the plate surface direction from the central portion, and a rigid reinforcing plate provided on an outer surface of the closed portion, wherein the closed portion And a rigid reinforcing plate having a central portion that is fixed to the outer surface and an extending portion that extends outward from the central portion in the plate surface direction.
In this case, the extension part of the reinforcing plate and the extension part of the protection plate are connected via a spacer.

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

A protective container can be provided instead 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 an outer periphery of the protective member and the elastic plate. And 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 closing portion.

  Also with such a configuration, deformation of the elastic plate due to external force can be more effectively suppressed, 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 a foamable resin is provided in the accommodation space of the piezoelectric element surrounded by the cylindrical portion in plan view so as to surround the piezoelectric element.

  According to such a configuration, leakage of sound waves from the first surface side 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 constraining region so as to open the first surfaces of the vibration region, the low-rigidity region, and the boundary region. Can be provided.
In this case, the cylindrical portion is disposed 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 cylindrical portion. .

  According to such a configuration, it is possible to suppress the vibration of the restriction 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 configuration having the mass member, a sound absorbing material made of foaming resin is preferably provided in the accommodation space of the piezoelectric element surrounded by the mass member in plan view so as to surround the piezoelectric element.

  In order to achieve the first object, according to a second aspect of the present invention, there is provided an elastic plate having a first surface and a second surface facing the one side and the other side in the plate thickness direction, respectively, and capable of 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 board, A plurality of vibration regions to which a plurality of piezoelectric elements are respectively attached; a plurality of low-rigid regions that respectively surround the plurality of vibration regions in a plan view; and a plurality of constraint regions that respectively surround the plurality of low-rigid regions in a plan view. A boundary region that divides one constrained region and an outer region located radially outward from the one constrained region, and the low-rigid region is the vibration located radially inward of the region The region and the region located radially outward of the region. The boundary region has a slit portion that divides one constraining region and the outer region, and a bridge portion that mechanically connects the one constraining region to the outer region. The mass member is fixed to the first surface of the constraining region so as to surround the low-rigidity region in plan view while opening the first surface 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 an upper electrode layer of the plurality of piezoelectric elements. An ultrasonic transducer having a plurality of tip regions electrically connected to each other is provided.

According to the ultrasonic transducer of the second aspect of the present invention, vibration is propagated between the plurality of vibrating bodies via 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, it is possible to effectively radiate low-frequency ultrasonic waves while effectively preventing or reducing mutual interference between the plurality of piezoelectric elements.

  Furthermore, in the ultrasonic transducer, the vibration region is flexibly supported through the low-rigidity region, and a low resonance frequency can be realized even if the area of the vibration region is reduced. The sound pressure can be increased.

  In the ultrasonic transducer, since the flexible wiring board is not directly fixed to the elastic plate, but is fixed to the upper surface of the mass member, the flexible wiring board is formed of 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 restraining 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, in the accommodation space of the piezoelectric element surrounded by the mass member in a plan view, a sound absorbing material made of foaming resin is provided so as to surround the piezoelectric element.

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

  In the second aspect, in the configuration in which the mass member includes a plurality of restraint region mass members fixed to the first surfaces of the plurality of restraint regions so as to surround the plurality of low rigidity regions, respectively, in plan view. Preferably, the ultrasonic transducer further includes a plurality of cylindrical portions provided in the boundary region so as to surround the plurality of constraining region mass members in a plan view, and free of the plurality of cylindrical portions. 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, external contact 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 outward is fixed to the second surface of the elastic plate.

  According to such a configuration, external contact 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, it is possible to effectively prevent damage to the surface of the protective member and to suppress vibration of the surface of the protective member.

Also in the second aspect, instead of the protective plate and the reinforcing plate, a rigid protective plate provided on the outer surface of the protective member, which is fixed to the outer surface of the protective member, and the opening of the protective member And a rigid protective plate having a central portion provided with a through hole at a position corresponding to, and an extending portion extending outward from the central portion in the plate surface direction, and a rigid reinforcing plate provided on the outer surface of the closed portion And the rigid reinforcement board which has the center part fixed to the outer surface of the said obstruction | occlusion part, and the extension part extended in the plate | board surface direction outward from the said center part can be provided.
In this case, the extension part of the reinforcing plate and the extension part of the protection plate are connected via a spacer.

  According to such a configuration, deformation of the elastic plate due to external force can be more effectively suppressed, 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 instead 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 an outer periphery of the protective member and the elastic plate. And 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 closing portion.

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

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

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

  Alternatively, the low-rigidity region may be a concave thin region where the first surface is closer to the second surface than the first surface of the vibration region and the restraining region.

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

In the configuration in which the low rigidity region is the concave thin region, the bottom surface of the thin region is preferably a raised portion lower than the first surface of the vibration region, and is shared with the inner surface of the thin region. A ridge is provided that acts to form an adhesive stagnation 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 various configurations of the first and second aspects, for example, the plurality of constraining regions are formed by m constraining regions (m is an integer of 1 or more) arranged along the first plate surface direction 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 in the second plate surface direction of the one piezoelectric element attached to the vibration region in the one constraining region, and extend along the first plate surface direction. A first plate surface direction slit, and a pair of second plate surface direction slits located on both sides of the first 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. The four portions defined by the end portions 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.

In order to achieve the second object, the present invention includes an elastic plate having a first surface and a second surface facing the one side and the other side in the plate thickness direction, respectively, and capable of vibrating in the plate thickness direction, A plurality of piezoelectric elements fixed in parallel to a first surface of the plate, a sealing member having a plurality of cylindrical portions surrounding each of the plurality of piezoelectric elements in plan view, and a flexible wiring board, The elastic plate surrounds the plurality of vibration regions to which the plurality of piezoelectric elements are respectively attached, the plurality of low rigidity regions that surround the plurality of vibration regions in plan view, and the plurality of low rigidity regions in plan view, respectively. A plurality of constraining regions, a boundary region that divides one constraining region and an outer region located radially outward from the one constraining region, and the low-rigidity region is radially inward of the region The vibration region located in Rigidity is lower than that of the constraining region located outward in the direction, and the boundary region includes a slit portion that divides one constraining region and the outward region, and one constraining region mechanically into the outer region. The flexible wiring board has an insulating layer fixed to the upper surface of the cylindrical portion, and a wiring conductor provided on the upper surface of the insulating layer, and the wiring conductor Is a method of manufacturing an ultrasonic transducer having a plurality of tip regions that are electrically connected to the upper surface electrode layers of the plurality of piezoelectric elements, respectively, and etching a conductive elastic plate forming body Performing an elastic plate forming step to form the elastic plate, and a piezoelectric element mounting step of bonding the lower surface electrode layers of the plurality of piezoelectric elements to the first surfaces of the plurality of vibration regions with a conductive adhesive, respectively, That of multiple low-rigidity areas A cylindrical part installation step of installing the plurality of cylindrical parts so as to surround the planar view in a plan view, and a flexible wiring board in which a wiring conductor is provided on the upper surface of the insulating layer, wherein the wiring conductor includes the insulation Providing a flexible wiring board having a main body region located on the layer and a plurality of tip regions extending from the main body region so as to extend outward from the insulating layer; and Flexible wiring that is fixed to the upper surface of the cylindrical portion with an adhesive, and electrically connects the connection terminals for the piezoelectric elements in the plurality of tip regions to the upper surface electrode layers of the plurality of piezoelectric elements with a conductive adhesive or solder, respectively. A step of preparing the flexible wiring board, including at least a step before the flexible wiring board mounting step, the elastic plate forming step, and the piezoelectric element mounting step. And the 1st manufacturing method of the ultrasonic transducer performed independently from the said cylindrical part installation process is provided.

  In order to achieve the second object, the present invention includes an elastic plate having a first surface and a second surface facing the one side and the other side in the plate thickness direction, respectively, and capable of vibrating in the plate thickness direction, A plurality of piezoelectric elements fixed in parallel to a first surface of the plate, a sealing member having a plurality of cylindrical portions surrounding each of the plurality of piezoelectric elements in plan view, and a flexible wiring board, The elastic plate surrounds the plurality of vibration regions to which the plurality of piezoelectric elements are respectively attached, the plurality of low rigidity regions that surround the plurality of vibration regions in plan view, and the plurality of low rigidity regions in plan view, respectively. A plurality of constraining regions, a boundary region that divides one constraining region and an outer region located radially outward from the one constraining region, and the low-rigidity region is radially inward of the region The vibration region located in Rigidity is lower than that of the constraining region located outward in the direction, and the boundary region includes a slit portion that divides one constraining region and the outward region, and one constraining region mechanically into the outer region. The flexible wiring board has an insulating layer fixed to the upper surface of the cylindrical portion, and a wiring conductor provided on the upper surface of the insulating layer, and the wiring conductor Is a method of manufacturing an ultrasonic transducer having a plurality of tip regions that are electrically connected to the upper surface electrode layers of the plurality of piezoelectric elements, respectively, and etching a conductive elastic plate forming body Performing an elastic plate forming step to form the elastic plate, and a piezoelectric element mounting step of bonding the lower surface electrode layers of the plurality of piezoelectric elements to the first surfaces of the plurality of vibration regions with a conductive adhesive, respectively, That of multiple low-rigidity areas A cylindrical part installation step of installing the plurality of cylindrical parts so as to surround the planar view in a plan view, and a flexible wiring board in which a wiring conductor is provided on the upper surface of the insulating layer, wherein the wiring conductor includes the insulation Providing a flexible wiring board having a main body region located on the layer and a plurality of tip regions extending from the main body region so as to extend outward from the insulating layer; and Flexible wiring that is fixed to the upper surface of the cylindrical portion with an adhesive, and electrically connects the connection terminals for the piezoelectric elements in the plurality of tip regions to the upper surface electrode layers of the plurality of piezoelectric elements with a conductive adhesive or solder, respectively. A step of preparing the flexible wiring board, including at least a step before the flexible wiring board mounting step, the elastic plate forming step, and the piezoelectric element mounting step. And the 1st manufacturing method of the ultrasonic transducer performed independently of the said sealing member installation process is provided.

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

  In the first manufacturing method, before the tubular portion installation step, a protective member provided with an opening that opens the vibration region outward is opened to the vibration region outward through the opening. However, 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 cylindrical portion installation step, the elastic plate is formed so that the sealing member integrally has a filling portion extending from the proximal end surface of the cylindrical portion to the inside of the slit portion in addition to the cylindrical portion. Including a process of applying and curing a first polymer material on a cylindrical portion installation region surrounding the low-rigidity region in a plan view in the slit portion and on the first surface of the elastic plate from one surface side It is said.

  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 surrounding the whole of the plurality of constraining regions in a plan view.

  In this case, in the first manufacturing method, after the piezoelectric element mounting step, the first surface of the constraining region is constrained to the first surface of the vibration region, the low-rigidity region, and the boundary region. There is provided a mass member installation step including a process of fixing the area mass member and a process of fixing the base area mass member to the base area.

  In the first manufacturing method, the step of preparing the flexible wiring board includes a sheet-like insulating layer forming member for forming the insulating layer and a sheet-like conductor for 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 etching away unnecessary portions of the conductor forming member to form the wiring conductor having a predetermined shape; and The insulating layer forming member is formed by etching away unnecessary portions of the insulating layer forming member so as to form the insulating layer having a predetermined shape.

  In the cylindrical portion installation step, a second height in which the upper surfaces of the plurality of cylindrical portions are 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. In the case where the plurality of cylindrical portions are disposed so as to be positioned at the position, preferably, the step of preparing the flexible wiring board includes the plurality of the plurality of cylindrical portions after the process of forming the insulating layer. The front end portion of the front end region overlaps with the upper surface electrode layer of the corresponding piezoelectric element in a plan view when the flexible wiring board is mounted, and the height with respect to the first surface of the elastic plate is the first height. The tip region is processed to be bent so as to be positioned at a third height that is lower than the second height and equal to or higher than the first height.

  In order to achieve the second object, the present invention includes an elastic plate having a first surface and a second surface facing the one side and the other side in the plate thickness direction, respectively, and capable of vibrating in the plate thickness direction, 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 cylindrical portions surrounding each of the plurality of piezoelectric elements in plan view And a flexible wiring board, wherein the elastic plate includes a plurality of vibration regions to which the plurality of piezoelectric elements are respectively attached, and a plurality of low stiffnesses that respectively surround the plurality of vibration regions in a plan view. A region, a plurality of constraining regions that respectively surround the plurality of low-rigid regions in plan view, a base region that encloses the plurality of constraining regions in plan view, and one adjacent constraining region and another constraining region And adjacent restraining areas and The low-rigidity region is located between the vibration region and the region in the radial direction of the region. Rigidity is lower than that of the constraining region located radially outward, and the boundary region mechanically connects the one constraining region with a slit portion that divides the one constraining region from the periphery. The mass member includes a plurality of restraint region mass members secured to the plurality of restraint regions, and a base region mass member secured to the base region. The wiring board includes an insulating layer fixed to an upper surface of the restraining region mass member, 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 electrically connected to A method of manufacturing an ultrasonic transducer having a plurality of tip regions, wherein 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 bonding the lower surface electrode layers of the plurality of piezoelectric elements to the first surface of the vibration area with a conductive adhesive, and a process of fixing the mass member for the restraint area to each of the plurality of restraint areas; A mass member installation step including a process of fixing the base region mass member to the base region; and a flexible wiring board in which a wiring conductor is provided on an upper surface of the insulating layer, wherein the wiring conductor is disposed on the insulating layer. Providing a flexible wiring board having a main body region located at a plurality of tip regions extending from the main body region so as to extend outward from the insulating layer; and An insulating layer is fixed to the upper surface of the mass member for the constraining region by an adhesive, and the piezoelectric element connection terminals in the plurality of tip regions are electrically connected to the upper electrode layers of the plurality of piezoelectric elements by a conductive adhesive or solder, respectively. A step of preparing the flexible wiring board including at least a step before the flexible wiring board mounting step, the elastic plate forming step, the piezoelectric element mounting step, and the mass member. A second method for manufacturing an ultrasonic transducer, which is performed independently of an installation process, is provided.

  According to the second manufacturing method, the ultrasonic transducer having the above-described configuration can be manufactured at a low cost and with a high yield.

  In the second manufacturing method, the step of preparing the flexible wiring board includes a sheet-like insulating layer forming member for forming the insulating layer and a sheet-like conductor for 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 etching away unnecessary portions of the conductor forming member to form the wiring conductor having a predetermined shape; and The insulating layer forming member is formed by etching away unnecessary portions of the insulating layer forming member so as to form the insulating layer having a predetermined shape.

  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 electrode layer of the piezoelectric element, with the first surface of the elastic plate as a reference. In the case where the restraint region mass member is to be installed so as to be positioned, preferably, the step of preparing the flexible wiring board includes the plurality of tips after the process of forming the insulating layer. When the flexible wiring board is mounted, the tip in the region overlaps with the upper electrode layer of the corresponding piezoelectric element in plan view, and the height with respect to the first surface of the elastic plate is the second. The tip region is processed to be bent so as to be located at a third height that is lower than the first height and higher than the first height.

  In the second manufacturing method, preferably, the mass member installation step includes the plurality of constraint region mass members, the base region mass member, one adjacent constraint region mass member, and another constraint region. A mass plate is provided that includes a bridge between restraint areas that connects the upper ends of the mass members for use, and a bridge between the restraint area / base area that couples the upper ends of the mass members for the adjacent restraint area and the base area. A process of fixing the mass plate to a predetermined position of the first surface of the elastic plate, cutting the bridge between the restraint areas and the bridge between the restraint areas / base areas, and thereby massing the plurality of restraint areas. And a process of separating the member and the mass member for the base region.

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

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

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

  In the first and second manufacturing methods, the low-rigidity region is a groove that opens toward the first surface provided along the outer peripheral edge of the vibration region, or along the outer peripheral edge of the vibration region. In the case where the plurality of openings provided are a plurality of openings in which the connecting portions are left between the openings adjacent in the circumferential direction, the elastic plate forming step is performed by etching. The slit or the groove of the low rigidity region or the plurality of openings are formed.

  In the first and second manufacturing methods, the low rigidity region includes a first surface 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 constraint region. It is a concave thin-walled area that opens to the side, and the bottom surface of the thin-walled area is a raised portion that is lower than the first surface of the vibration area and the constraining area, and is bonded together with the inner side surface of the thin-walled area A raised portion that forms an 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 extended portion that extends radially outward from the surface 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-retaining region In the elastic plate forming step. In the etching, a full etching process for forming the slit portion and half etching from the first surface side to the region corresponding to the low rigidity region to form the low rigidity region which is a concave thin wall region. And a half-etching process.

  In the half etching process, a region corresponding to the vibration region and a region corresponding to the constraining region are covered with a mask, and a region corresponding to the raised portion is covered with a mask having a width smaller than twice the side etching amount. In this state, the raised portion lower than the vibration region and the constraining region is left on the bottom surface of the concave thin region while the low rigidity region is a concave thin region that opens to the first surface side. The

  In order to achieve the second object, the present invention includes an elastic plate having a first surface and a second surface facing the one side and the other side in the plate thickness direction, respectively, and capable of vibrating in the plate thickness direction, A plurality of piezoelectric elements fixed in parallel to the first surface of the plate, and a flexible wiring board fixed to the first surface of the elastic plate, wherein the elastic plate is mounted with the plurality of piezoelectric elements, respectively. A plurality of vibration regions, a plurality of low-rigid regions surrounding each of the plurality of vibration regions in plan view, a plurality of constraint regions surrounding each of the plurality of low-rigid regions in plan view, one constraint region, and the one A boundary region that divides the outer region located radially outward from the restraining region, and the low-rigidity region includes the vibration region located radially inward of the region and the radially outer side of the region. Compared with the restraining region located on the side, the rigidity is low. The boundary region includes an ultrasonic transformer having a slit portion that divides the one constraining region and the outer region, and a bridge portion that mechanically connects the one constraining region to the outer region. A method of manufacturing a reducer, comprising: forming an elastic plate by etching a conductive elastic plate forming body; and forming a plurality of piezoelectric elements on a first surface of the plurality of vibration regions. A piezoelectric element mounting step in which the lower surface electrode layers are respectively bonded with a conductive adhesive, a step of preparing a flexible wiring board in which a wiring conductor is provided on the upper surface of the insulating layer, and a predetermined position on the first surface of the elastic plate Insulating layer fixing process for fixing the insulating layer with an adhesive, and electrical connection for electrically connecting the tip portions of the plurality of wiring conductors to the corresponding upper electrode layer of the piezoelectric element with a conductive adhesive or solder A step of preparing the flexible wiring board, wherein the step of preparing the flexible wiring board is executed independently of the elastic plate forming step and the piezoelectric element mounting step. A manufacturing method is provided.

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

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

  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, It is provided so that the front-end | tip part of these wiring conductors may be electrically connected to the upper surface electrode layer of the said piezoelectric element corresponding.

FIG. 1 is a longitudinal sectional view of an ultrasonic transducer according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 1, and illustration of some components is omitted for easy understanding. FIG. 3 is an enlarged view of a portion III in FIG. FIG. 4 is an enlarged view of a portion IV in FIG. 2, and illustration of a sealing member is omitted for easy understanding. FIG. 5 is a partially enlarged plan view of the ultrasonic transducer according to the first modification of the first embodiment, and shows a state in which some constituent members are removed. FIG. 6 is a partially enlarged plan view of the ultrasonic transducer according to the second modification of the first embodiment, and shows a state in which some constituent members are removed. FIG. 7 is a plan view of an ultrasonic transducer according to a third modification of the first embodiment, showing a state in which some components are removed. FIG. 8 is a plan view of an ultrasonic transducer according to a fourth modification of the first embodiment, showing a state in which some constituent members are removed. 9A to 9C are process diagrams of the method of manufacturing the ultrasonic transducer according to the first embodiment. FIG. 10 is a process diagram of the manufacturing method subsequent to FIG. FIG. 11 is a process diagram of the manufacturing method subsequent to FIG. FIG. 12 is a process diagram of the manufacturing method following FIG. 13A to 13E are process diagrams of a process for preparing a flexible wiring board in the manufacturing method. FIG. 14 is a process diagram of the manufacturing method subsequent to 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 longitudinal sectional view of an ultrasonic transducer according to a fifth modification of the first embodiment. FIG. 18 is a longitudinal sectional view of an ultrasonic transducer according to a sixth modification of the first embodiment. FIG. 19 is a longitudinal sectional view of an ultrasonic transducer according to a seventh modification of the first embodiment. FIG. 20 is a longitudinal sectional view of an ultrasonic transducer according to an eighth modification of the first embodiment. FIG. 21 is a longitudinal sectional view of an ultrasonic transducer according to Embodiment 2 of the present invention. FIG. 22 is a cross-sectional view taken along the line XXII-XXII in FIG. 21, and illustration of some components is omitted for easy understanding. FIG. 23 is an enlarged view of part XXIII in FIG. FIG. 24 is a process diagram of the method of manufacturing the ultrasonic transducer according to the second embodiment. FIG. 25 is a process diagram of the manufacturing method following FIG. FIG. 26 is a process diagram of the manufacturing method, following FIG. FIG. 27 is a process diagram of the manufacturing method, following FIG. FIG. 28 is a process diagram of the manufacturing method, following FIG. FIG. 29 is a process diagram of the manufacturing method following FIG. FIG. 30 is a process diagram of the method of manufacturing an ultrasonic transducer according to the second embodiment, and is a plan view showing a state in which a mass plate is fixed. 31 is a longitudinal sectional view taken along line XXXI-XXXI in FIG. FIG. 32 is an enlarged view of a portion XXXII in FIG. FIG. 33 is an enlarged view corresponding to FIG. 32 and shows a state where the bridge between the restraint areas and the bridge between the restraint areas / base areas in the mass plate are cut. FIG. 34 is a longitudinal sectional view of an ultrasonic transducer according to a first modification of the second embodiment. FIG. 35 is a longitudinal sectional view of an ultrasonic transducer according to a second modification of the second embodiment. FIG. 36 is a partial longitudinal sectional view of an ultrasonic transducer according to Embodiment 3 of the present invention. FIG. 37 is a plan view of the ultrasonic transducer according to the third embodiment. 38A to 38C are process diagrams of the method for manufacturing the ultrasonic transducer according to the third embodiment. FIG. 39 is a partial longitudinal sectional view of an ultrasonic transducer according to a first modification of the third embodiment. FIG. 40 is a partial longitudinal sectional view of an ultrasonic transducer according to a second modification of the third embodiment. FIG. 41 is a longitudinal sectional view of an ultrasonic transducer manufactured by the manufacturing method according to Embodiment 4 of the present invention. FIG. 42 is a cross-sectional plan view taken along the line XXXXII-XXXXII in FIG. 41, and shows some components omitted. FIG. 43 is an enlarged view of a portion XXXXIII in FIG. 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 a portion XXXXVII in FIG.

Embodiment 1
Hereinafter, an embodiment of an ultrasonic transducer according to the present invention will be described with reference to the accompanying drawings.
FIG. 1 shows a longitudinal sectional view of an ultrasonic transducer 1A according to the present embodiment.
2 and 3 show a cross-sectional view taken along line II-II in FIG. 1 and an enlarged view of part III, respectively.
In FIG. 2, the illustration of the following closed portion 44 and the following sound absorbing material 50 in the ultrasonic transducer is omitted for easy 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 the one side and the other side in the plate thickness direction, respectively. Sealing having a plurality of piezoelectric elements 30 fixed in parallel to the first surface 10a of the elastic plate 10 in the plate surface direction and a plurality of cylindrical portions 42 surrounding each of the plurality of piezoelectric elements 30 in plan view. A member 40 and a flexible wiring board 80 serving as a voltage supply path for the plurality of piezoelectric elements 30 are provided.

The elastic plate 10 is made of various materials such as a metal plate such as stainless steel, Ni-Fe alloy, aluminum alloy, titanium alloy, carbon fiber reinforced plastic, and ceramics as long as it has elasticity capable of vibrating in the thickness direction. obtain.
The elastic plate 10 has a thickness of 0.03 mm to 0.1 mm, for example.
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 and lower electrode layers disposed on both sides of the piezoelectric main body in the thickness direction.
The piezoelectric body has a thickness of 0.05 mm to 0.3 mm, for example, and the upper electrode layer and the lower electrode layer are made of Ag or Au having a thickness of 0.05 μm to several μm, for example.

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

  Specifically, as shown in FIGS. 1 to 3, the elastic plate 10 surrounds the plurality of vibration regions 12 to which the plurality of piezoelectric elements 30 are respectively attached and the plurality of vibration regions 12 in a plan view. A plurality of low-rigid regions 26, a plurality of constraining regions 14 that respectively surround the plurality of low-rigid regions 26 in plan view, and one constraining region 14 and an outer side located radially outward from the one constraining region 14 A boundary region 16 that divides the region is provided.

  As shown in FIG. 2, the ultrasonic transducer 1 </ b> A according to the present embodiment includes m pieces (five pieces in the illustrated embodiment) arranged along the first plate surface direction D <b> 1 of the elastic plate 10. M appears when a constrained region group 14A formed by the constrained regions 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. There are × n (5 × 3 = 15 in the illustrated form) the constraining regions 14.

Similarly, m × n of the plurality of low-rigidity regions 26 surrounded by the plurality of constraining regions 14 are provided, and the plurality of vibration regions 12 in which the plurality of low-rigidity regions 26 are respectively surrounded are similarly m × n. n 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 whole of the plurality of constraining regions 14 in plan view.

  In this case, among the plurality of constraining regions 14, for the constraining region 14 located on the outermost periphery, for example, the constraining region 14 (1-1) located in the first row from the top and the first column from the left in FIG. , A constraining area 14 adjacent to the right side (constraint area 14 (1-2) located in the first row from the top and in the second column from the left), a constraining area 14 adjacent to the lower side (in the second line from the top and The constraining area 14 (2-1) located in the first column from the left and the base area 11 adjacent to the upper side and the left side are the outer areas facing each other with the boundary area 16 in between.

  For the restraint area 14 surrounded by another restraint area, for example, the restraint area 14 (2-2) located in the second row from the top and the second column from the left in FIG. Adjacent constrained region 14 (first row from top and constrained region 14 (1-2) in the second column from the left), constraining region 14 adjacent to the right side (second row from the top and the third column from the left) Constraining area 14 (2-3)), constraining area 14 adjacent to the lower side (the constraining area 14 (3-2) in the third row from the top (bottom row) and the second column from the left), and the left side The adjacent constraining area 14 (the constraining area 14 (2-1) in the second row from the top and the first column from the left) is the outer area facing the boundary area 16.

  In the present embodiment, as shown in FIG. 2, the plurality of constraining regions 14 are arranged in a lattice pattern, but the plurality of vibration regions 12 are naturally limited to such an arrangement. Instead, they may be arranged in a staggered pattern, a radial pattern, or the like.

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

FIG. 4 is an enlarged view of a portion IV in FIG. 2 and shows a state in which the sealing member 40 is omitted for easy understanding.
As shown in FIG. 4, the boundary region 16 divides one constraining region 14 in which the boundary region 16 defines an outer peripheral edge and the outer region adjacent to the outer side in the radial direction of the one constraining region 14. The slit part 17 and the bridge part 18 which maintains the mechanical connection with respect to the said outer area | region of the said one restraint area | region 14 are provided.

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

  Thus, in the ultrasonic transducer 1A according to the present embodiment, a plurality of vibration regions 12 surrounded by the low-rigidity region 26 are provided on one elastic plate 10, and the plurality of vibrations A plurality of piezoelectric elements 30 are attached to each of the regions 12, and as close proximity arrangement as possible between the plurality of vibration regions 12 vibrated by the plurality of piezoelectric elements 30 can be realized. Furthermore, the slit portion 17 of the boundary region 16 can effectively prevent or reduce the vibration of the one vibration region 12 from propagating to the outer region located radially outward of the one vibration region 12. Can do.

  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 includes an insulating layer 82 and a wiring conductor 85 provided on the upper surface of the insulating layer 82.

The insulating layer 82 is made of polyimide having a thickness of about 18 μm to 25 μm, for example.
The wiring conductor 85 is made 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 cylindrical portion 42 of the sealing member 40 with an adhesive.

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

  The insulating layer is formed so that the tip region 85b forms a piezoelectric element connection terminal electrically connected to the upper surface electrode layer of the piezoelectric element 30 corresponding to the tip portion via a conductive adhesive or solder 87. 82 extends outward.

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

  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 Each of the plurality of piezoelectric elements 30 can be individually operated via the.

The flexible wiring board 80 may be modified 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. 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 electrode layer is positioned at a first height with respect to the first surface 10 a of the elastic plate 10. On the other hand, the cylindrical portion 42 is configured such that the upper surface 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, the tip region 85b of the wiring conductor 85 is superimposed on the upper electrode layer of the piezoelectric element 30 in the plan view, and the piezoelectric element connection terminal is based on the first surface 10a of the elastic plate 10. It is comprised so that it may be located in the 3rd height below the 1st height below the 2nd height position.

  According to such a configuration, the connecting operation between the piezoelectric element connection terminal 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 cylindrical portion 42. it can.

  In the present embodiment, as shown in FIG. 3, the tip region 85b has a front, rear, and rear inclined portion that is positioned downward as it goes to the tip side. Instead of this, it is also possible to have a vertically extending portion 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 lower electrode layer pad 89. 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 has a main body of the wiring conductor 85 in order to prevent the wiring conductor 85 from coming into contact with the outside. An insulating cover layer 83 is provided to cover part or all of the region 85a excluding the upper 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 separated from the elastic plate 10 in the sealed state. It is fixed to the upper surface of the cylindrical 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 cylindrical portion 42 into the slit portion 17 in addition to the plurality of cylindrical portions 42. And a filling portion 41 extending in the direction.

  According to such a configuration, the posture of the restraining region 14 is obtained while effectively preventing or reducing the vibration of one vibration region 12 from propagating to another adjacent vibration region 12 by the slit portion 17. It is possible to stabilize the operation of the vibration region 12.

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

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

  Specifically, as described above and as shown in FIG. 3, the upper surface of the cylindrical portion 42 is positioned at a second height that is higher than the first height at which the upper surface electrode layer of the piezoelectric element 30 is positioned. The closing portion 44 is provided so as to leave a gap between the upper surface electrode layer of the piezoelectric element 30.

  In addition, an accommodation space for accommodating the piezoelectric element 30 surrounded by the first surface 10a of the elastic plate 10, the cylindrical portion 42, and the closing portion 44 is formed of a foamable resin such as foamable silicone. The sound absorbing material 50 is filled.

  By providing the sound absorbing material 50, it is possible to prevent or reduce leakage of ultrasonic waves from the vibration region 12 to the rear side (the first surface 10a side with respect to the thickness direction of the elastic plate 1), and burst-like ultrasonic waves. After radiating, the reverberation of the ultrasonic wave can be effectively suppressed.

As shown in FIGS. 1 and 3, the ultrasonic transducer 1 </ b> A according to the present embodiment further includes 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 vibration characteristics.

As shown in FIGS. 1 and 3, the ultrasonic transducer 1 </ b> A according to the present embodiment is further a protection member 70 joined to the second surface 10 b of the elastic plate 10, and the vibration region 12 is 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 vibration characteristics.

The ultrasonic transducer 1 </ b> A further includes a rigid protective plate 75 joined 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 a metal plate such as stainless steel, Ni-Fe alloy, aluminum alloy, titanium alloy, etc. having a thickness of about 0.1 mm to 0.5 mm.

  By providing the protective plate 75, it is possible to effectively prevent the protective member 70 from vibrating unexpectedly while effectively preventing or reducing damage to the protective member 70.

  In the present embodiment, as shown in FIG. 4, the slit portions 17 are positioned on both sides of the second plate surface direction D <b> 2 of the one piezoelectric element 30 attached to the vibration region 12 in the one restraining region 14. A pair of first plate surface direction slits 17a extending along the first plate surface direction D1 and the first plate surface direction D1 of the one piezoelectric element 30 are located on both sides of the first plate surface direction D1, and in the second plate surface direction D2. It includes a pair of second plate surface direction slits 17b extending along.

  The pair of first plate surface direction slits 17 a is longer than the first plate surface direction length 30 a of the one piezoelectric element 30, and the pair of second plate surface direction slits 17 b is the second of the one piezoelectric element 30. The plate surface direction length is longer than 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 in the circumferential direction. The bridge portion 18 is provided.

  According to such a configuration, it is possible to stably hold the plurality of constraining regions 14 while effectively preventing vibration from propagating between the plurality of piezoelectric elements 30 arranged in a rectangular shape.

  In the present embodiment, as described above, only a single boundary region 16 exists between the adjacent constraining regions 14, and the constraining region where the slits 17 of the single boundary region 16 are adjacent. 14 shows the outer periphery of both.

  According to such a configuration, the installation area of the plurality of constraining regions 14 can be reduced 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 can have various configurations.
FIG. 5 shows a partially enlarged plan view of an ultrasonic transducer 1B according to a first modification having a slit portion 21 and a bridge portion 22 having different configurations.
Also in FIG. 5, illustration of the sealing member and the sound absorbing material is omitted.

In the first modified example 1B shown in FIG. 5, the slit portion 21 has an arc shape.
And the four said slit parts 21 are comprised so that the one restraint area | region 14 may be surrounded, and the said bridge part 22 is provided between the two said slit parts 21 adjacent to the circumferential direction.

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

In the second modified example 1C shown in FIG. 6, the slit portion 23 is substantially L-shaped in plan view.
And the four said slit parts 23 are comprised so that the one restraint area | region 14 may be enclosed.

  Specifically, two L-shaped slits 23 adjacent to each other in the circumferential direction overlap in the circumferential direction in a state in which a part 23a of one slit 23 is located radially inward from a part 23b of the other slit 23. A radial gap between a portion 23 a of the one slit 23 and a portion 23 b 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), 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 restraining 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 10 a of the elastic plate 10 is the same as the first surface 10 a. 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 can be used as an alignment mark when the piezoelectric element 30 is mounted on the vibration region 12 while the low rigidity region 26 is formed by the groove 27.

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

In 3rd modification 1D shown in FIG. 7, the opening part 28a which divides the inside and outside of the said vibration area | region 12 in the area | region along the outer periphery of the said vibration area | region 12 among the said elastic board 10, and the inside and outside of the said vibration area | region 12 Are connected alternately in the circumferential direction, and the low rigidity region 26 is formed by the opening 28a and the connecting portion 28b.
Similarly to the groove 27, the opening 28a and the connecting portion 28b can also be used as alignment marks when the piezoelectric element 30 is mounted in the vibration region 12.

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 the above. It is not limited to such a form.
FIG. 8 is a plan view of an ultrasonic transducer 1E according to a fourth modification that includes a vibration region 12 and a piezoelectric element 30 that are rectangular in plan view, and includes the closing portion 44 and the sound absorbing portion of the sealing member 40. The top view of the state which deleted the material 50 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 elastic plate 10 is formed by etching the conductive elastic plate forming body 110.

  Etching in the elastic plate forming step includes the formation of grooves 27 in the region along the outer peripheral edge of the vibration region 12 in the first surface 10a of the elastic plate 10 (FIG. 9A), and the slit portion. 17 is formed (FIG. 9B).

  In the present embodiment, first, the groove 27 is formed by half etching, and then the slit portion 17 is formed. However, the order of forming the groove 27 and the slit portion 17 is not limited.

  Further, when the low-rigidity region 26 is exposed by the plurality of openings 28a as in the modification 1D, the etching in the elastic plate forming step is not the formation of the groove 27, but the vibration A plurality of openings 28a are formed along the outer peripheral edge of the region 12, and a plurality of openings 28a in which the connecting portions 28b are left between the openings 28a adjacent in the circumferential direction are formed. .

  The manufacturing method includes a piezoelectric element mounting step in which the lower surface electrode layers of the plurality of piezoelectric elements 30 are respectively bonded to the first surfaces 10 a of the plurality of vibration regions 12 by the conductive adhesive 38.

  Specifically, the piezoelectric element mounting step includes a step of applying a conductive adhesive 38 to the first surface 10a of the plurality of vibration regions 12 (FIG. 9C), and a top of the conductive adhesive 38. And attaching the piezoelectric element 30 to cure the conductive adhesive 38 (FIG. 10).

  9 (a) to 9 (c) is a gold plating provided on the first surface 10a of the vibration region 12 before the application of the conductive adhesive 38. This is to improve the reliability of electrical connection with the first surface 10a of the vibration region 12.

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

  The protective member 70 is fixed to the second surface 10 b 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. Is 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 pre-assembly by previously bonding the protective plate 75 to the outer surface of the protective plate 70. And a process of bonding the protective pre-assembly to the second surface 10b of the elastic plate 10.

  Needless to say, the protective member installation step and the protective plate installation step are performed by bonding the protective member 70 to the second surface 10b of the elastic plate 10 and bonding the protective plate 75 to the outer surface of the protective member 70. It is also possible to modify so as to have a processing to be performed.

Next, the manufacturing method includes a cylindrical part installation step of installing the cylindrical part 42.
As shown in FIG. 12, the tubular portion installation step includes forming a tubular portion mold 49 that delimits an area (cylindrical portion installation region) in which the tubular portion 42 is to be provided in an open state. A process of installing, and a process of applying and curing a first polymer material such as silicone in the cylindrical part mold frame 49 from the first surface 10a side of the elastic plate 10.

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

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

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

At this time, the opening on the lower side (the second surface side of the elastic plate) of the slit portion 17 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 located below the slit portion 17 (on the second surface side). 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 application of the first polymer material to the tubular portion installation region. Thus, a curing process 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 performed independently of the elastic plate forming step, the piezoelectric element mounting step, the protection member installation step, the protection plate installation step, and the cylindrical 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 cylindrical portion installing step, or these It is also possible to execute in parallel with this process.

  Specifically, the step of preparing the flexible wiring board 80 includes a sheet-like insulating layer forming member 182 that forms the insulating layer 82 and a sheet-like conductor that forms the wiring conductor 85 on the upper surface of the insulating layer forming member 182. A process of preparing a wiring sheet body 180 in which the forming members 185 are laminated (FIG. 13A) is included.

For example, the insulating layer forming member 182 is made of 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 away unnecessary portions of the conductor forming member 185 to form the wiring conductor 85 having a predetermined shape (FIG. 13B).

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

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

  In the step of preparing the flexible wiring board 80, the piezoelectric element connection terminal formed by the distal end portion of the distal end region 85b is superposed on the upper electrode layer of the piezoelectric element 30 corresponding in plan view, and The tip region 85b is bent so that the height of the piezoelectric element connection terminal relative to the first surface 10a of the elastic plate 10 is located at the third height (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 includes an installation process for 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. 13C).
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 a process of fixing the insulating layer 82 to the upper surface of the tubular portion 42 with an adhesive, and conductive bonding of the piezoelectric element connection terminals to the corresponding upper electrode layer of the piezoelectric element 30. And electrical and mechanical connection 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 performed.

The ultrasonic transducer 1A according to the present embodiment includes 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 and cure a foamable resin such as foamable silicone that forms the sound absorbing material 50 in the sound absorbing material installation space surrounded by the cylindrical portion 42. (FIG. 15).

As described above, in the present embodiment, the sealing member 40 has the closing portion 44.
Therefore, the said manufacturing method has the obstruction | occlusion part installation process which installs the said obstruction | occlusion part 44 after the said sound-absorbing material installation process (FIG. 16).

  The blocking 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 high viscosity 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, a curing temperature (for example, 100 ° C. to 150 ° C.) is applied after the second polymer material is applied to the upper surface of the cylindrical portion 42 and the sound absorbing material 50. ) Can be cured.

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

Instead of this, it is possible to simultaneously install the blocking portion 44 and the reinforcing plate 60.
That is, the blocking portion 44 is formed separately, the reinforcing plate 60 is adhered to the outer surface of the blocking portion 44, the blocking plate-with-reinforcing plate is formed in advance, and the blocking plate-with-reinforcing plate is formed as the cylindrical portion 42. It is also possible to install the blocking portion and the reinforcing plate 60 by fixing the sound absorbing material 50 and the flexible wiring board 80 so as to cover them.

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

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

  As shown in FIG. 18, in the sixth modified example 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, the ultrasonic transducer 1A according to the present embodiment includes a flat protective plate 75 (see FIG. 1 and the like), but it is also possible to include a protective container 175 instead of the protective plate 75. is there.

  FIG. 20 is a longitudinal sectional view of an ultrasonic transducer 1I according to an eighth modification including 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 formed in the central portion. 72 from the peripheral edge of the end wall portion 176 so as to surround the end wall portion 176 provided with a through hole 177 at a position corresponding to 72 and the side walls of the protection member 70, the elastic plate 10 and the sealing member 44. And 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 side surfaces of the protective member 70, the elastic plate 10, and the cylindrical portion 42, and the blocking portion 44 is provided 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 longitudinal sectional view of the ultrasonic transducer 2A according to the present embodiment.
22 and 23 show a cross-sectional view and an enlarged view of the XXIII portion taken along line XXII-XXII in FIG. 21, respectively.
In the figure, the same members as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted as appropriate.
For ease of understanding, illustration of the closing portion 44 and the sound absorbing material 50 is omitted in FIG.

  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 In place of the reinforcing plate 60 and the protective plate 75, the ultrasonic transducer 1A according to the first embodiment is provided with a reinforcing plate 260 and a protective plate 275 connected to each other via a spacer 250. Is different.

  The mass member 210 is fixed to the first surface 10 a 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 restraining region 14 so as to surround the vibration region 12 and the low-rigidity region 26 in plan view. And a base region mass member 210b fixed to the base region 11 so as to surround the entirety of the plurality of constraining regions 14 in plan view.

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 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 including the mass member 210, it is possible to effectively or reduce that the restraint region 14 vibrates due to vibration propagating from the vibration region 12.

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

  In the present embodiment, the cylindrical portion 44 has a restraint region mass member 210a fixed to one restraint region 14 surrounding one low rigidity region 26 and the restraint region 14 with respect to the restraint region 14. Mass member 210 (constraint region mass member 210a or base region mass member 210b) fixed to an outer region (another constraining region 14 adjacent thereto or the adjacent base region 11) opposed across the boundary region 16 ) And the upper surface is located at the same second height as the upper surface of the mass member 210.

  In addition, the sound absorbing material 50 includes the restraint region mass member 210a secured to the restraint region 14 surrounding the vibration region 12 to which the corresponding piezoelectric element 30 is secured as a mold, and the piezoelectric element in the mass member 210a. 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 formed in a state where the insulating layer 82 of the flexible wiring board 80 is fixed to the upper surface of the mass member 100 and the cylindrical portion 42. The connection terminal for electrical connection 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 this embodiment, the flexible wiring board 80 can effectively prevent or reduce deterioration of the vibration characteristics of the vibration region 12.

  As shown in FIG. 21, the protective plate 275 is overlapped with the protective member 70 in a plan view and has a central portion 276 provided with the through-hole 77 and an extension extending 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 with the through hole 77 and the opening 72 being aligned.

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

The extending portion 264 of the reinforcing plate 260 and the extending portion 278 of the protection 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 cylindrical body, and the reinforcing plate 260 is extended through a screw member 255 inserted into the hollow portion of the spacer 250. The existing part 264 and the extending part 278 of the protection plate 275 are connected.

  Alternatively, the spacer 250 may be bonded to the extending portion 264 of the reinforcing plate 260 and the extending portion 278 of the protection plate 275.

  Thus, by connecting the reinforcing plate 260 and the protective plate 275 via the spacer 250, the strength of the ultrasonic transducer 2A can be improved.

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

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

  In the present embodiment, as shown in FIG. 24, the mass member installation step includes a process of fixing the restraint region mass members 210a to the plurality of restraint regions 14, respectively, and the entire restraint regions 14 as a whole. The base region mass member 210b is fixed to a predetermined part of the base region 11 surrounding the base region 11.

  As described above, the constrained area mass member 210a and the base area 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 and Ni-Fe alloy. They are fixed in place by spot welding with an adhesive or laser.

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

  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 pre-assembly in which the protective plate 275 is bonded in advance to the outer surface of the protective member 70. And a process of bonding the protective pre-assembly to the second surface 10b of the elastic plate 10.

  Needless to say, the protective member installation step and the protective plate installation step are performed by bonding the protective member 70 to the second surface 10b of the elastic plate 10 and bonding the protective plate 275 to the outer surface of the protective member 70. It is also possible to modify so as to have a processing to be performed.

  In addition, the said protection member installation process and the said protection board installation process can also be performed before the said mass member installation process.

  The manufacturing method includes a cylindrical portion installation step (FIG. 26) in which the cylindrical portion 42 is installed before the mass member installation step and the protection member installation step are completed.

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

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

  The steps for preparing the flexible wiring board 80 are the elastic plate forming step, the piezoelectric element mounting step, the protection member installation step, the protection plate installation step, and the cylindrical portion installation step, as in the first embodiment. It is executed independently.

  In the flexible wiring board mounting step, the insulating layer 82 is fixed to the upper surface of the mass member 210 and the upper surface of the cylindrical portion 42 with an adhesive, and the piezoelectric element connection terminals are connected to the corresponding piezoelectric element 30. And a process of electrically and mechanically connecting the upper electrode layer with a conductive adhesive or solder 87 (FIG. 27).

Next, the manufacturing method includes 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 is to be installed is surrounded by the restraining region mass member 210a, and therefore, foaming is performed so as to cover the piezoelectric element 30 in the space surrounded by the restraining region mass member 210a. The sound absorbing material 50 can be stably installed by filling a foamable resin such as a conductive 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 protection plate 275 and the extending portion 264 of the reinforcing plate 260 via the spacer 250. Yes.

  The said manufacturing method has the said obstruction | occlusion part installation process after the said reinforcement board installation process (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 communicating with the inner surface and the outer surface. 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 blocking 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 for the base region 11 at a predetermined position. And a process of fixing the mass member 210b.

  Here, the plurality of restraint area mass members 210a and the base area mass members 210b are separate from each other, and accordingly, the plurality of restraint area mass members 210a and the base area mass members 210b. For each of these, an alignment process and a fixing process are required.

  In this regard, if the mass plate 200 in which the plurality of mass region members 210a and the base region mass members 210b are integrally connected via the bridges 215 and 216 described below, the mass member installation step is performed. Simplification and high speed can be achieved.

FIG. 30 is a plan view of a pre-assembly in which the mass plate 200 is fixed to the elastic plate 10 after the piezoelectric element mounting step.
31 and 32 show a cross-sectional view along the line XXXI-XXXI in FIG. 30 and an enlarged view of the XXXII part in FIG. 31, respectively.

  As shown in FIGS. 30 to 32, the mass plate 200 includes a plurality of restraint area mass members 210a, a base area mass member 210b, an adjacent restraint area mass member 210a, and other restraint areas. A constrained-area bridge 215 that connects the upper ends of the area mass members 210a, and a constrained area / base-area bridge 216 that connects the upper ends of the adjacent restricted area mass members 210a and base area mass members 210b. have.

  The restraint region bridge 215 and the restraint region / base region bridge 216 are 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 mass member for restraint area 210a and the mass member for base area 210b. Can be efficiently formed by half-etching the region corresponding to the constraining region bridge 215 and the constraining region / base region bridge 216 from the surface of one side of the metal block.

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

  The mass member installation process 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, the inter-restraint region bridge 215, and the constraint region / base region. The bridge 216 is cut to separate the plurality of restraining area mass members 210a and the base area mass members 210b.

  FIG. 33 shows a longitudinal sectional view corresponding to FIG. 32 in a state in which the bridge 215 between the restraint areas and the bridge 216 between the restraint areas / base areas are cut.

  The cutting between the restraint region bridge 215 and the restraint region / base region bridge 216 can be performed by, for example, laser light irradiation.

  According to the mass member installation process using the mass plate 200, it is only necessary to perform the alignment process and the fixing process once when the mass members 210a and 210b are installed, and the mass member 210a and 210b can be simply and quickly installed. Can be achieved.

Various modifications can be made to the ultrasonic transducer 2A according to the present embodiment.
34 and 35 show longitudinal 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 protection plate 75 instead of the protection plate 275, as compared with the ultrasonic transducer 2A according to the present embodiment, and the reinforcement plate. 260 has been deleted.

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

  The ultrasonic transducer 3A according to the present embodiment mainly includes 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 cylindrical portion 42. The ultrasonic wave transducer 1A according to the first embodiment is different 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 omitted, and that the mass member 210 is provided. .

  The elastic plate 310 has a first surface 310a and a second surface 310b facing the 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 plate 310 is provided in a parallel state in the plate surface direction, and a plurality of vibration regions 312 to which the plurality of piezoelectric elements 330 are respectively attached, and the plurality of the plurality of piezoelectric regions 330 in a plan view. A plurality of low-rigidity regions 326 that respectively surround the vibration region 312, a constraining region 314 that respectively surrounds the plurality of low-rigidity regions 326 in plan view, and one constraining region 314 and one constraining region 314 that is radially outward. And a boundary region 316 that partitions the outer region.

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

  The boundary region 316 includes the slit portion 17 and the bridge portion 18 in the same manner as the boundary region 16.

  The low-rigidity region 326 is a concave thin region that opens to the first surface side, the first surface of which is closer to the second surface than the first surfaces of the vibration region 312 and the constraining region 314.

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

The piezoelectric element 330 has an outer diameter larger than the vibration area 312 and smaller than the low rigidity area 326.
That is, the piezoelectric element 330 includes 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. 333.

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

As shown in FIG. 36 and FIG. 37, in the present embodiment, the piezoelectric element connection terminal corresponds in a state where 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 this embodiment, the flexible wiring board 80 can effectively prevent or reduce 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 plan view, the piezoelectric element 330 has a rectangular shape in plan view, and the low-rigidity region 326 has a rectangular shape in plan view. 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 area 312 and smaller than the outer diameter of the low-rigidity area 326, the vibration area 312, the piezoelectric element 330, and the low diameter are reduced. Various shapes are possible, for example, all of the rigid region 326 is circular in plan view.

Preferably, the low-rigidity region 326 has the same outer shape as the piezoelectric element 330 and 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 joined by the insulating adhesive 340 to stabilize the support of the piezoelectric element 330. The low-rigidity region 326 and the lower electrode layer of the extending portion 333 of the piezoelectric element 330 are connected by a conductive adhesive 345 to electrically connect the lower electrode layer of the piezoelectric element 330 and the elastic plate 310. Have gained.

  Furthermore, in the ultrasonic transducer 3A, as shown in FIG. 36, the bottom surface (first surface) of the thin 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 that cooperates with the inner surface of the thin region to form an adhesive staying 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 surface electrode layer of the extending portion 333 of the piezoelectric element 330, and the low rigidity The conductive adhesive 345 that electrically connects the region 326 is mixed unexpectedly and effectively prevents the reliability of the electrical connection between the lower electrode layer of the piezoelectric element 330 and the elastic plate 310 from being impaired. can do.

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

  The ultrasonic transducer 3A according to the present embodiment can be suitably manufactured, for example, by a manufacturing method with the following changes compared to 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 removing the slit portion 17 by etching. It has a half-etching process (FIG. 38 (a)).

  In 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 side etching amount. As a result, the raised portion 328 can be left so that the position of the top of the raised portion 328 is lower than the first surface 310a of the vibration region 312 and the constraining region 314, and contact with the lower surface of the piezoelectric element 330 can be prevented. it can.

  Next, a conductive adhesive 328 is applied to the adhesive staying region, and an insulating adhesive 340 is applied to the vibration region 312 (FIG. 38B), and after the piezoelectric element 330 is mounted (FIG. 38 ( c)), the conductive adhesive 328 and the insulating adhesive 340 are cured.

  Note that reference numeral 346 in FIG. 36 indicates that before the application of the conductive adhesive 345 to the adhesive staying region, in order to improve the reliability of the electrical connection between the conductive adhesive 345 and the elastic plate 310, It is Au plating provided in the 1st surface of the said adhesive agent retention area | region.

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

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

Embodiment 4
Hereinafter, a 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.
42 and 43 are respectively a cross-sectional plan view and an XXXXIII enlarged view taken along line XXXXII-XXXXII in FIG.
In the figure, the same members as those in the first to third embodiments are denoted by the same reference numerals, and detailed description thereof is omitted as appropriate.
In FIG. 42, the cylindrical portion and the sound absorbing material are not shown for easy understanding.

  The ultrasonic transducer 4A is different from the ultrasonic transducer 1A according to the first embodiment only in that the flexible wiring board 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 according to 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 board 80 independently of the elastic plate formation step and the piezoelectric element mounting step, the protection member installation step, and the protection plate installation step ( A step of mounting the flexible wiring board 80 before or after FIG.

  The step of preparing the flexible wiring board 80 includes a sheet-like insulating layer forming member 182 that forms the insulating layer 82 and a sheet-like conductor forming member 185 that forms the wiring conductor 85 on the upper surface of the insulating layer forming member 182. 44 is prepared (FIG. 44 (a)).

For example, the insulating layer forming member 182 is made of 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 away unnecessary portions of the conductor forming member 185 to form the wiring conductor 85 having a predetermined shape (FIG. 44B).

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

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 includes an installation process for 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) for fixing the insulating layer 82 of the flexible wiring board 80 to a predetermined position of the first surface 10a of the elastic plate 10 with an adhesive; And an electrical connection process (FIGS. 46 and 47) for electrically connecting the leading end of the wiring conductor 85 to the corresponding upper electrode layer of the piezoelectric element 30 by 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 electrode layer and the lower electrode layer, the manufacturing method according to the present embodiment includes: Before the electrical connection process, there is a process (FIG. 47) of applying an insulating adhesive 88 between the tip portions of the plurality of wiring conductors 85 and the corresponding piezoelectric elements 30.

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

  The manufacturing method according to the present embodiment is similar to the manufacturing method according to the first embodiment, after the protective member installation step and the protection plate installation step (see FIG. 11), the cylindrical portion installation step (FIG. 12). The sound absorbing material installation step (see FIG. 15), the blocking 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 transducer 10, 310 Elastic plate 10a, 310a First surface 10b, 310b Second surface 11, 311 Base region 12, 312 Vibration region 14, 314 Restriction region 16 316 Boundary region 17 Slit portion 17a, 17b First and second plate surface direction slit 18 Bridge portion 26, 326 Low rigidity region 27 Groove 28a Opening portion 28b Connecting portion 30, 330 Piezoelectric element 40 Sealing member 41 Filling portion 42 Tube Shaped part 44 Blocking part 50 Sound absorbing material 60, 260 Rigid reinforcing 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 Line conductor forming member 210 Mass member 210a Mass member for restraint area 210b Mass member for base area 215 Bridge between restraint areas 216 Bridge between restraint area / base area 250 Spacer 328 Raised part 331 Central part 333 Extension part 340 Insulating adhesive 345 Conductive adhesive

Claims (42)

An elastic plate having a first surface and a second surface facing the one side and the other side in the plate thickness direction, respectively, and a plurality of piezoelectric members fixed in parallel to the first surface of the elastic plate An element, a sealing member having a plurality of cylindrical portions surrounding each of the plurality of piezoelectric elements in a plan view, and a flexible wiring board,
The elastic plate includes a plurality of vibration regions to which the plurality of piezoelectric elements are respectively attached, a plurality of low rigidity regions surrounding the plurality of vibration regions in plan view, and the plurality of low rigidity regions in plan view, respectively. A plurality of constraining regions that surround, and a boundary region that divides one constraining region and an outer region located radially outward from the one constraining region,
The low-rigidity region is low-rigidity compared to the vibration region located radially inward of the region and the restraining region located radially outward of the region,
The boundary region has a slit portion that divides one constraining region and an outer region, and a bridge portion that mechanically connects the one constraining region to the outer region,
The plurality of cylindrical portions are arranged so as to surround the plurality of low-rigidity regions in plan view,
The flexible wiring board has an insulating layer fixed to the upper surface of the cylindrical 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 having a plurality of tip regions electrically connected to each other. The wiring conductor has a main body region located on the insulating layer, and the plurality of tip regions extending from the main body region so as to extend outward from the insulating layer,
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 respectively polymerized on a corresponding upper surface electrode layer of the 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 electrode layer is positioned at a first height with respect to the first surface of the elastic plate, and the upper surface of the cylindrical portion is based on the first surface of the elastic plate. Configured to be located at a second height higher than the first height,
The tip region is configured such that the piezoelectric element connection terminal is located below a second height with respect to the first surface of the elastic plate and at a third height equal to or higher than the first height. The ultrasonic transducer according to claim 2. The cylindrical part is arranged so that the base end face straddles the slit part,
The said sealing member has the filling part extended in the inside of the said slit part from the base end surface of the said cylindrical part in addition to the said cylindrical part, The Claim 1 characterized by the above-mentioned. The described ultrasonic transducer.   The ultrasonic transducer according to claim 4, wherein the sealing member further includes a closing portion that closes a free end side of each of the plurality of cylindrical portions. The cylindrical part and the filling part are integrally formed of a first polymer material, and the blocking part is formed of a second polymer material,
The ultrasonic transducer according to claim 5, wherein the first polymer material has a lower viscosity than the second polymer material on the basis of a state before curing.   The ultrasonic transducer according to claim 5 or 6, wherein a rigid reinforcing plate is fixed to an outer surface of the blocking portion.   The ultrasonic transducer according to claim 7, wherein a protective member having an opening that opens the vibration region outward is fixed to the second surface of the elastic plate.   9. The ultrasonic transducer according to claim 8, wherein a rigid protective plate having a through hole provided 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, the protective member provided with an opening that opens the vibration region outward;
A rigid protective plate provided on the outer surface of the protective member, the protective plate having 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 blocking portion,
The protective plate has a central portion fixed to the outer surface of the protective member, and an extending portion extending outward from the central portion in the plate surface direction,
The reinforcing plate has a central portion that is fixed to the outer surface of the closing portion, and an extending portion that extends outward from the central portion in the plate surface direction,
The ultrasonic transducer according to claim 5 or 6, wherein the extension part of the reinforcing plate and the extension part of the protection plate are connected via a spacer. A protective member fixed to the second surface of the elastic plate, the protective member provided with an opening that opens the vibration region outward;
An end wall extending along the outer surface of the protective member and having a through hole at a position corresponding to the opening of the protective member, and from the end wall so as to surround the outer periphery of the protective member and the elastic plate A protective container including an extending peripheral wall;
The reinforcing plate connected to the peripheral wall portion so as to close the free end opening of the peripheral wall portion of the protective container in a state of covering the outer surface of the closed portion. Ultrasonic transducer.   12. The sound absorbing material made of foamable resin is provided in the accommodation space of the piezoelectric element surrounded by the cylindrical portion in plan view so as to surround the piezoelectric element. The ultrasonic transducer in any one. A mass member fixed to the first surface of the restraining region so as to open the first surface of the vibration region, the low-rigidity region, and the boundary region;
The cylindrical part is arranged so that the base end face straddles the slit part,
The ultrasonic transducer according to claim 1, 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 cylindrical portion.   14. The super-acoustic material according to claim 13, wherein a sound absorbing material made of foamable resin is provided in a housing space of the piezoelectric element surrounded by the mass member in plan view so as to surround the piezoelectric element. Sonic transducer. An elastic plate having a first surface and a second surface facing the one side and the other side in the plate thickness direction, respectively, and a plurality of piezoelectric members fixed in parallel to the first surface of the elastic plate An element, a mass member fixed to the first surface of the elastic plate, and a flexible wiring board,
The elastic plate includes a plurality of vibration regions to which the plurality of piezoelectric elements are respectively attached, a plurality of low rigidity regions surrounding the plurality of vibration regions in plan view, and the plurality of low rigidity regions in plan view, respectively. A plurality of constraining regions that surround, and a boundary region that divides one constraining region and an outer region located radially outward from the one constraining region,
The low-rigidity region is low-rigidity compared to the vibration region located radially inward of the region and the restraining region located radially outward of the region,
The boundary region has a slit portion that divides one constraining region and an outer region, and a bridge portion that mechanically connects the one constraining region to the outer region,
The mass member is fixed to the first surface of the restraining region so as to surround the low rigidity region in a plan view while opening the first surface 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 electrode layer of the plurality of piezoelectric elements. An ultrasonic transducer having a plurality of tip regions that are electrically connected to each other.   16. The super-acoustic material according to claim 15, wherein a sound absorbing material made of foaming resin is provided in a housing space of the piezoelectric element surrounded by the mass member in plan view so as to surround the piezoelectric element. Sonic transducer. The mass member has a plurality of restraint region mass members respectively fixed to the first surfaces of the plurality of restraint regions so as to surround the plurality of low rigidity regions in plan view,
The ultrasonic transducer further closes the plurality of cylindrical portions provided in the boundary region so as to surround the plurality of constraining region mass members in a plan view and the free end sides of the plurality of cylindrical portions, respectively. 17. The ultrasonic transducer according to claim 15, further comprising: a sealing member including a closing portion to be fixed; and a rigid reinforcing plate fixed to an 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 outward is fixed to the second surface of the elastic plate.   The ultrasonic transducer according to claim 18, wherein a rigid protective plate having a through hole at a position corresponding to the opening is fixed to an outer surface of the protective member. The mass member has a plurality of restraint region mass members respectively fixed to the first surfaces of the plurality of restraint regions so as to surround the plurality of low rigidity regions in plan view,
The ultrasonic transducer further closes the plurality of cylindrical portions provided in the boundary region so as to surround the plurality of constraining region mass members in a plan view and the free end sides of the plurality of cylindrical portions, respectively. A sealing member including a closing portion to be
A protective member fixed to the second surface of the elastic plate, the protective member provided with an opening that opens the vibration region outward;
A rigid protective plate provided on the outer surface of the protective member, the protective plate having 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 blocking portion,
The protective plate has a central portion fixed to the outer surface of the protective member, and an extending portion extending outward from the central portion in the plate surface direction,
The reinforcing plate has a central portion that is fixed to the outer surface of the closing portion, and an extending portion that extends outward from the central portion in the plate surface direction,
The ultrasonic transducer according to claim 15 or 16, wherein the extension part of the reinforcing plate and the extension part of the protection plate are connected via a spacer. The mass member has a plurality of restraint region mass members respectively fixed to the first surfaces of the plurality of restraint regions so as to surround the plurality of low rigidity regions in plan view,
The ultrasonic transducer further closes the plurality of cylindrical portions provided in the boundary region so as to surround the plurality of constraining region mass members in a plan view and the free end sides of the plurality of cylindrical portions, respectively. A sealing member including a closing portion to be
A protective member fixed to the second surface of the elastic plate, the protective member provided with an opening that opens the vibration region outward;
An end wall extending along the outer surface of the protective member and having a through hole at a position corresponding to the opening of the protective member, and from the end wall so as to surround the outer periphery of the protective member and the elastic plate A protective container including an extending peripheral wall;
The reinforcing plate connected to the peripheral wall portion so as to close the free end opening of the peripheral wall portion of the protective container in a state of 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 in a first surface of the elastic plate.   The low-rigidity region includes an opening that divides between the vibration region and the restraining region, and a connecting portion that connects the vibration region and the restricting region, and the opening and the connecting portion are the vibrations. The ultrasonic transducer according to any one of claims 1 to 21, wherein the ultrasonic transducer is alternately provided along an 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 constraint 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 extension portion is electrically connected to the first surface of the low rigidity region by a conductive adhesive. The ultrasonic transducer according to any one of claims 1 to 21, wherein the ultrasonic transducer is mechanically and mechanically connected. The bottom surface of the thin region is provided with a raised portion that is lower than the first surface of the vibration region and forms an adhesive retention region in cooperation with the inner surface of the thin 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. Item 25. The ultrasonic transducer according to Item 24. The plurality of constraining regions are a constraining region group formed by m constraining regions (m is an integer of 1 or more) arranged along the first plate surface direction of the elastic plate, and orthogonal to the first plate surface direction. N rows (n is an integer of 1 or more) in the second plate surface direction, and m × n restricted regions that are revealed by being provided,
The slit portions are located on both sides in the second plate surface direction of the one piezoelectric element mounted in the vibration region in the one constraining region, and extend along the first plate surface direction. Including a slit and a pair of second plate surface direction slits located on both sides in the first plate surface direction of the one piezoelectric element 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 ’s long,
The four portions defined by the end portions 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. The ultrasonic transducer according to any one of 25.   27. A single common slit is provided between adjacent constraining regions, and the single common slit defines both outer peripheral edges of adjacent constraining regions. Ultrasonic transducer. An elastic plate having a first surface and a second surface facing the one side and the other side in the plate thickness direction, respectively, and a plurality of piezoelectric members fixed in parallel to the first surface of the elastic plate An element, a sealing member having a plurality of cylindrical portions surrounding each of the plurality of piezoelectric elements in a plan view, and a flexible wiring board, and the elastic plate includes a plurality of the plurality of piezoelectric elements to which the plurality of piezoelectric elements are mounted. Vibration regions, a plurality of low-rigid regions that respectively surround the plurality of vibration regions in plan view, a plurality of constraint regions that respectively surround the plurality of low-rigid regions in plan view, one constraint region, and the one constraint A boundary region that divides an outer region located radially outward from the region, and the low-rigid region is located in the vibration region located radially inward of the region and radially outward of the region. Compared to the restrained area located The boundary region has a slit portion that divides one constraining region and the outer region, and a bridge portion that mechanically connects the one constraining region to the outer region, and the flexible wiring The plate has an insulating layer fixed to the upper surface of the cylindrical portion and a wiring conductor provided on the upper surface of the insulating layer, and the wiring conductor is electrically connected to the upper electrode layers of the plurality of piezoelectric elements. A method of manufacturing an ultrasonic transducer having a plurality of tip regions that are connected to each other,
An elastic plate forming step of etching the conductive elastic plate forming body to form the elastic plate;
A piezoelectric element mounting step in which the lower surface electrode layers of the plurality of piezoelectric elements are respectively bonded to the first surfaces of the plurality of vibration regions by a conductive adhesive;
A cylindrical portion installation step of installing the plurality of cylindrical portions so as to surround each of the plurality of low rigidity regions in plan view;
A flexible wiring board having a wiring conductor provided on an upper surface of an insulating layer, wherein the wiring conductor extends from the main body region so as to extend outward from the main body region and the main body region located on the insulating layer. Preparing a flexible wiring board having a plurality of existing tip regions;
The insulating layer is fixed to the upper surface of the cylindrical portion with an adhesive, and the piezoelectric element connection terminals in the plurality of tip regions are electrically connected to the upper electrode layers of the plurality of piezoelectric elements by a conductive adhesive or solder, respectively. Including a flexible wiring board mounting process to be connected,
The step of preparing the flexible wiring board is performed independently of the elastic plate forming step, the piezoelectric element mounting step, and the cylindrical portion installation step at least before the flexible wiring board mounting step. The manufacturing method of the ultrasonic transducer characterized by these.
Before the cylindrical portion installation step, a protective member provided with an opening that opens the vibration region outward is provided on the second surface of the slit portion while opening the vibration region outward through the opening. A protective member installation step for adhering to the second surface of the elastic plate so as to close the side,
In the cylindrical portion installation step, the elastic plate is formed so that the sealing member integrally has a filling portion extending from the proximal end surface of the cylindrical portion to the inside of the slit portion in addition to the cylindrical portion. Including a process of applying and curing a first polymer material on a cylindrical portion installation region that surrounds the low-rigidity region in a plan view inside the slit portion and on the first surface of the elastic plate from one surface side. The method of manufacturing an ultrasonic transducer according to claim 28. The elastic plate forming step is to form the elastic plate so that the elastic plate has a base region surrounding the whole of the plurality of constraining regions in a plan view,
After the piezoelectric element mounting step, a process of fixing a plurality of constraining area mass members to the first surfaces of the constraining areas so as to surround the plurality of low rigidity areas, respectively, in plan view, and a base in the base area 30. The method of manufacturing an ultrasonic transducer according to claim 28, further comprising a mass member installation step including a process of fixing the region mass member. The step of preparing the flexible wiring board includes:
A process of preparing a sheet-like insulating layer forming member for forming the insulating layer and a wiring sheet body in which a sheet-like conductor forming member for forming the wiring conductor is laminated on an upper surface of the insulating layer forming member;
A process of forming the wiring conductor of a predetermined shape by etching away unnecessary portions of the conductor forming member;
And a process of forming an insulating layer having a predetermined shape by etching away 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 cylindrical portion installation step, a second height in which the upper surfaces of the plurality of cylindrical portions are 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. It is assumed that the plurality of cylindrical portions are installed so as to be located at
In the step of preparing the flexible wiring board, after the process of forming the insulating layer, the tip portions of 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 overlapped with the electrode layer, and the height relative to the first surface of the elastic plate is positioned below the second height and at a third height equal to or higher than the first height. 32. The method of manufacturing an ultrasonic transducer according to claim 31, further comprising a bending process. An elastic plate having a first surface and a second surface facing the one side and the other side in the plate thickness direction, respectively, and a plurality of piezoelectric members fixed in parallel to the first surface of the elastic plate An element, a mass member fixed to the first surface of the elastic plate, a sealing member having a plurality of cylindrical portions surrounding each of the plurality of piezoelectric elements in plan view, and a flexible wiring board, The elastic plate surrounds the plurality of vibration regions to which the plurality of piezoelectric elements are respectively attached, the plurality of low rigidity regions that surround the plurality of vibration regions in plan view, and the plurality of low rigidity regions in plan view, respectively. A plurality of constraining regions, a base region surrounding the entirety of the plurality of constraining regions in plan view, located between one adjacent constraining region and another constraining region, and between adjacent constraining regions and a base region, Multiple restraints The low-rigidity region is compared to the vibration region located radially inward of the region and the constraining region located radially outward of the region. The boundary region has a slit portion that divides the one constraining region from the periphery, and a bridge portion that mechanically connects the one constraining region to the periphery, and the mass member includes A plurality of restraint region mass members each secured to a plurality of restraint regions; and a base region mass member secured to the base region, wherein the flexible wiring board is secured to the upper surface of the restraint region mass member And a wiring conductor provided on the top surface of the insulating layer, the wiring conductor having a plurality of tip regions electrically connected to the top electrode layers of the plurality of piezoelectric elements, respectively. Ultrasonic tiger A Sudeyusa method of manufacturing,
An elastic plate forming step of etching the conductive elastic plate forming body to form the elastic plate;
A piezoelectric element mounting step in which the lower surface electrode layers of the plurality of piezoelectric elements are respectively bonded to the first surfaces of the plurality of vibration regions by a conductive adhesive;
A mass member installation step including a process of fixing the mass member for the restraint area to each of the plurality of restraint areas and a process of fixing the mass member for the base area to the base area;
A flexible wiring board having a wiring conductor provided on an upper surface of an insulating layer, wherein the wiring conductor extends from the main body region so as to extend outward from the main body region and the main body region located on the insulating layer. Preparing a flexible wiring board having a plurality of existing tip regions;
The insulating layer is fixed to the upper surface of the mass member for the constraining region by an adhesive, and the piezoelectric element connection terminals in the plurality of tip regions are electrically connected to the upper electrode layers of the plurality of piezoelectric elements by a conductive adhesive or solder, respectively. Including a flexible wiring board mounting process to be connected,
The step of preparing the flexible wiring board is performed independently of the elastic plate forming step, the piezoelectric element mounting step, and the mass member installation step at least before the flexible wiring board mounting step. A method for manufacturing an ultrasonic transducer. The step of preparing the flexible wiring board includes:
A process of preparing a sheet-like insulating layer forming member for forming the insulating layer and a wiring sheet body in which a sheet-like conductor forming member for forming the wiring conductor is laminated on an upper surface of the insulating layer forming member;
A process of forming the wiring conductor of a predetermined shape by etching away unnecessary portions of the conductor forming member;
And a process of forming an insulating layer having a predetermined shape by etching away 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 claim 33. In the mass member installing step, the upper surface of the mass member for the restraining 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. It is assumed that the mass member for the restraint region is installed so as to be positioned,
In the step of preparing the flexible wiring board, after the process of forming the insulating layer, the tip portions of 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 overlapped with the electrode layer, and the height relative to the first surface of the elastic plate is positioned below the second height and at a third height equal to or higher than the first height. The method for manufacturing an ultrasonic transducer according to claim 34, further comprising a bending process.   In the mass member installation step, the plurality of restraint region mass members, the base region mass member, the restraint for connecting the upper ends of the one restraint region mass member and the other restraint region mass member adjacent to each other. A process of preparing a mass plate including an inter-region bridge and a constrained region / base region bridge that connects the upper ends of adjacent constrained region mass members and base region mass members; and The process of adhering to a predetermined position of the first surface and cutting the bridge between the restraint areas and the bridge between the restraint areas / base areas to separate the plurality of restraint area mass members and the base area mass members. 36. The method of manufacturing an ultrasonic transducer according to any one of claims 33 to 35, further comprising: a processing.   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 restraining area and the mass member for the base area, and a surface on one side of the metal block. 37. The method of manufacturing an ultrasonic transducer according to claim 36, further comprising: half-etching a region corresponding to the restriction region bridge and the restriction region / base region bridge.   The step of preparing the flexible wiring board includes a process of installing an insulating cover layer so as to cover at least a part of a region of the wiring conductor that forms the main body region after the processing of forming the wiring conductor. 38. The method of manufacturing an ultrasonic transducer according to any one of claims 28 to 37, comprising: The low-rigidity region is a groove opened on the first surface side 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 a plurality of openings in which a connecting portion is left between openings adjacent in the circumferential direction,
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 manufacturing method of the ultrasonic transducer of description. The low-rigidity region is a concave thin-walled region that opens to 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 restraining region. ,
A raised portion that is lower than the first surface of the vibration region and the constraining region and that forms an adhesive retention region in cooperation with the inner surface of the thin region is provided on the bottom surface of the thin region. 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 extends radially outward from the center portion and in the plan view. An extension portion that terminates 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-storing region;
Etching in the elastic plate forming step is a concave thin-walled region by performing half-etching from the first surface side to a region corresponding to the low-rigidity region and a full etching process for forming the slit portion. Including a half-etching process to form a low-rigidity region,
In the half etching process, a region corresponding to the vibration region and a region corresponding to the constraining region are covered with a mask, and a region corresponding to the raised portion is covered with a mask having a width smaller than twice the side etching amount. In this state, the raised portion lower than the vibration region and the constraining region is left on the bottom surface of the concave thin region while the low rigidity region is a concave thin region that opens to the first surface side. 40. The method of manufacturing an ultrasonic transducer according to any one of claims 28 to 39, wherein: An elastic plate having a first surface and a second surface facing the one side and the other side in the plate thickness direction, respectively, and a plurality of piezoelectric members fixed in parallel to the first surface of the elastic plate And a flexible wiring board fixed to the first surface of the elastic plate, wherein the elastic plate includes a plurality of vibration regions to which the plurality of piezoelectric elements are respectively attached, and the plurality of vibration regions in plan view. A plurality of low-rigid regions surrounding each of the plurality of low-rigid regions in plan view, a single constraining region, and an outer region located radially outward from the one constraining region, The low-rigidity area is lower in rigidity than the vibration area located radially inward of the area and the restraining area located radially outward of the area. , The boundary region is the one constrained region and A slit portion that divides the Kigai lateral regions, said one restraining region to the outer region A manufacturing method of the ultrasonic transducer which has a bridge portion which mechanically connected,
An elastic plate forming step of etching the conductive elastic plate forming body to form the elastic plate;
A piezoelectric element mounting step in which the lower surface electrode layers of the plurality of piezoelectric elements are respectively bonded to the first surfaces of the plurality of vibration regions by a conductive adhesive;
Preparing a flexible wiring board in which a wiring conductor is provided on the upper surface of the insulating layer;
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 on the upper surface electrode layer of the piezoelectric element corresponding to the tips of the plurality of wiring conductors A flexible wiring board mounting process including an electrical connection process for electrical connection by,
The method of manufacturing an ultrasonic transducer is characterized in that the step of preparing the flexible wiring board is executed independently of the elastic plate forming step and the piezoelectric element mounting step. The flexible wiring board mounting step includes an insulating resin installation process in which an insulating resin is applied between the tip portions 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 plurality of the conductive adhesives 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. 42. The method of manufacturing an ultrasonic transducer according to claim 41, wherein a tip end portion of the wiring conductor is electrically connected to a corresponding upper surface electrode layer of the piezoelectric element.

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