JP6422792B2 - Ultrasonic transceiver - Google Patents

Description

  The present invention relates to an ultrasonic transmission / reception element and an ultrasonic transmission / reception apparatus using the same.

  Piezoelectric elements such as piezoelectric ceramics generate electrical energy when a force is applied, and expand and contract when a force is applied to generate a force. For this reason, it is used in various fields using such properties.

Patent Document 1 describes an invention of an ultrasonic sensor including a piezoelectric vibrator and a casing (claim 1). A piezoelectric vibrator made of a circular metal plate and piezoelectric ceramics is used (FIG. 1, paragraph number 0009).
This ultrasonic sensor has a problem that its use is limited because it requires a housing and is restricted, and the piezoelectric vibrator uses a metal plate. Therefore, it is rusted when used in a high humidity atmosphere. There is also a problem that may occur.

In Patent Document 2, an ultrasonic wave generation device 100 including an ultrasonic wave generation element 1 is shown in FIGS.
The ultrasonic wave generating element 1 includes a frame 2, a first bimorph type piezoelectric vibrator 3, and a second first bimorph type piezoelectric vibrator 4 (paragraph number 0025). The frame 2 is made of ceramics, the first bimorph piezoelectric vibrator 3 is made of a rectangular and flat piezoelectric ceramic 3a, and the second first bimorph piezoelectric vibrator 4 is a rectangular and flat plate. It is described that it consists of piezoelectric ceramics 4a (paragraph numbers 0026 to 0028).
The ultrasonic wave generating element 1 has a problem that its structure is complicated and ceramics are laminated, so that it is easily broken and durability is inferior.

JP 2004-128813 A JP 2013-88234 A

  It is an object of the present invention to provide an ultrasonic transmission / reception element that can be reduced in size as a whole, can prevent the occurrence of rust, and can improve durability, and an ultrasonic transmission / reception apparatus using the ultrasonic transmission / reception element. To do.

The present invention is an ultrasonic transmitting and receiving element having a plate-like piezoelectric element and a resin portion fixed to at least one surface of the plate-like piezoelectric element,
The resin part is fixed so as to form an internal space surrounded by the resin part and the plate-like piezoelectric element,
An ultrasonic transmitting / receiving element in which the internal space is a sealed space is provided.

Further, the present invention is an ultrasonic transmission / reception element having a plate-like piezoelectric element and a resin portion fixed to at least one surface of the plate-like piezoelectric element,
The resin part is fixed so as to form an internal space surrounded by the resin part and the plate-like piezoelectric element,
Provided is an ultrasonic transmission / reception element in which the resin part has an opening and the internal space communicates with the outside.

The transmission / reception element of the present invention is a transmission element that transmits an ultrasonic wave by expanding and contracting a piezoelectric element in a plane direction (length direction) by applying a voltage from an AC power source and amplifying vibration caused by the expansion and contraction in a resin part. Function.
When the ultrasonic wave is received, the transmitting / receiving element of the present invention amplifies it by the resin part and transmits it to the piezoelectric element, and expands and contracts the piezoelectric element in the surface direction (length direction) to convert it into electric energy. It functions as a receiving element to detect.
Since the resin portion has an annular plane portion and a dome portion formed inside the annular plane portion, it is amplified when transmitting an ultrasonic wave and amplified when receiving an ultrasonic wave. Therefore, the function of transmitting to the piezoelectric element is enhanced.
The ultrasonic transmission / reception element of the present invention can be used in an ultrasonic transmission / reception device.

  Since the transmitting / receiving element of the present invention is composed of a combination of a piezoelectric element and a resin, it can be reduced in size and weight, has no risk of rusting, and has high durability.

1 is a plan view of an ultrasonic transmission / reception element according to the present invention. However, a part of the resin portion is cut out and a part of the plate-like piezoelectric element is visible. (A) is sectional drawing to the thickness direction between the II-II lines of FIG. 1, (b) is sectional drawing to the thickness direction similar to (a) of embodiment different from FIG. (A) is a front view of the ultrasonic transmission / reception element of FIG. 1, (b) is a front view of the ultrasonic transmission / reception element which is an embodiment different from FIG. (A) is sectional drawing to the thickness direction between the II-II lines similar to FIG. 1 of embodiment different from FIG. 1, (b) is the same thickness of another embodiment different from (a). Sectional view to direction. (A) is a plan view of an ultrasonic transmission / reception element according to another embodiment of the present invention, (b) is a sectional view in the thickness direction of (a), and (c) is an embodiment different from (a). Sectional drawing of thickness direction. It is explanatory drawing of the measuring method using the test apparatus for testing the performance of the transmitting / receiving element of Example 1 and Comparative Example 1, (a) is a side view of the test apparatus, and (b) is a part of the test apparatus. Plan view.

(1) Ultrasonic Transmitting / Receiving Element Shown in FIGS. 1 to 4 An embodiment of the ultrasonic transmitting / receiving element 1 of the present invention will be described with reference to FIGS.
The ultrasonic transmission / reception element 1 includes a plate-like piezoelectric element 10 and a resin portion 20.

The plate-like piezoelectric element 10 has a property of expanding and contracting in the plane direction (diameter direction) when an AC voltage is applied.
The plate-like piezoelectric element 10 has a circular planar shape, but is not limited to a circular shape, and a shape corresponding to the usage form can be selected. For example, a triangle, a quadrangle, a pentagon, a polygon such as a hexagon, an ellipse, or the like can be selected.
The piezoelectric element 10 is preferably made of a known piezoelectric ceramic element such as zinc zirconate titanate (PZT), lead lanthanum zirconate titanate, lead titanate, barium titanate, and more preferably PZT.
The piezoelectric element 10 is electrically connected to a power source via a lead wire or a flexible cable (not shown) when in use.

In the embodiment shown in FIGS. 2A and 2B, the resin portion 20 has an annular flat surface portion 21 and a dome portion 22 formed inside the annular flat surface portion 21.
In the embodiment shown in FIGS. 2A and 2B, only the annular flat surface portion 21 of the resin portion 20 is fixed to the first surface 11 of the plate-like piezoelectric element 10, and the first surface 11 and the dome are fixed. An internal space 15 is formed between the portions 22.
2A, the dome portion 22 has a hemispherical shape, and FIG. 2B shows the dome portion 22 having a flat surface 22a at the apex portion thereof.

FIG. 3A shows an embodiment in which the internal space 15 of the dome 22 is a sealed space.
FIG. 3B shows an embodiment in which the dome portion 22 has an opening 23 and the internal space 15 of the dome portion 22 is not sealed and communicates with the outside. One or two or more openings 23 may be formed.

In the embodiment of the transmitting / receiving element 100 shown in FIGS. 4A and 4B, the resin portion 120 has a circular substrate portion 121 and a dome portion 122 formed on the circular substrate portion 121.
In the embodiment shown in FIGS. 4A and 4B, the entire surface of the circular substrate portion 121 of the resin portion 120 is fixed to the first surface 111 of the plate-like piezoelectric element 110. An internal space 115 is formed between the dome portions 122.
4A, the dome portion 122 has a hemispherical shape, and FIG. 4B shows the dome portion 122 having a flat surface 122a at the apex portion thereof.
The transmitter / receiver element 100 of the embodiment shown in FIGS. 4 (a) and 4 (b) may have a sealed internal space 115 as shown in FIG. 3 (a), and FIG. As shown, it may have an internal space 115 having an opening.

  The resin portions 20 and 120 shown in FIGS. 1 to 4 can select a shape corresponding to a use state in addition to a circular planar shape. For example, it can be selected from a polygon such as a triangle, a quadrangle, a pentagon, and a hexagon, an ellipse, and an indeterminate shape, but preferably has the same shape as the plate-like piezoelectric elements 10 and 110.

The ratio (d2 / d1) of the outer diameter d1 of the annular flat surface portion 21 of the resin portion 20 and the outer diameter d2 of the dome portion 22 of the resin portion 20 shown in FIGS. From the viewpoint of increasing, 0.4 to 0.8 is preferable, and 0.5 to 0.7 is more preferable.
The same applies to the resin part 120 shown in FIG.

The ratio (h1 / d1) between the outer diameter d1 of the annular flat surface portion 21 of the resin portion 20 and the height h1 from the first surface 11 of the piezoelectric element at the apex of the dome portion 22 of the resin portion 20 shown in FIGS. Is preferably 0.05 to 0.3, more preferably 0.1 to 0.2, from the viewpoint of improving the transmission / reception performance of the ultrasonic transmission / reception element 1.
The same applies to the resin part 120 shown in FIG.

In the ultrasonic transmission / reception element 1 shown in FIGS. 1 to 3, the thickness of the plate-like piezoelectric element 10 varies depending on the size of the ultrasonic transmission / reception element 1, but the outer diameter (plate-like) of the ultrasonic transmission / reception element 1 is different. When the outer diameter d1 of the piezoelectric element 10 and the resin portion 20 is 10 mm, 0.5 to 3 mm is preferable, and 0.5 to 1.5 mm is more preferable.
In the ultrasonic transmission / reception element 1 shown in FIGS. 1 to 3, the thickness of the resin portion 20 (annular flat surface portion 21) varies depending on the size of the ultrasonic transmission / reception element 1, but the outer diameter of the ultrasonic transmission / reception element 1 ( When the outer diameter d1 of the plate-like piezoelectric element 10 and the resin portion 20) is 10 mm, 0.5 to 3 mm is preferable, and 0.5 to 1.5 mm is more preferable.
The same applies to the ultrasonic transmitting / receiving element 100 shown in FIG.

In the ultrasonic transmitting / receiving element 1 shown in FIGS. 1 to 3, the thickness of the plate-like piezoelectric element 10 and the thickness of the resin portion 20 (annular plane portion 21) are preferably the same or approximate. .
In the ultrasonic transmission / reception element 1 shown in FIGS. 1 to 3, the thickness of the ultrasonic transmission / reception element 1 (total thickness of the plate-like piezoelectric element 10 and the resin portion 20) t <b> 1 and the outer diameter of the ultrasonic transmission / reception element 1 ( The ratio (t1 / d1) of the plate-like piezoelectric element 10 and the outer diameter d1 (t1 / d1) is preferably 0.05 to 0.3, and more preferably 0.1 to 0.2.
The same applies to the ultrasonic transmitting / receiving element 100 shown in FIG.

In the ultrasonic transmitting / receiving element 1 shown in FIGS. 1 to 3, the plate-like piezoelectric element 10 and the resin portion 20 can be the same size or different sizes, but the projected area of the piezoelectric element 10 (from the vertical direction) The projected area (A1) and the projected area (projected area from the vertical direction) (A2) of the resin part 20 are preferably A2 ≧ A1, more preferably A2 / A1 = 1.0 to 8.0, A2 / A1 = 1.0 to 7.0 is more preferable, and A2 / A1 = 1.0 to 6.5 is particularly preferable.
The same applies to the ultrasonic transmitting / receiving element 100 shown in FIG.

As resin (synthetic resin) which comprises the resin parts 20 and 120, the synthetic resin chosen from a well-known thermoplastic resin, a thermosetting resin, etc. can be used.
Known thermoplastic resins include cyclic olefin resins (such as ethylene-norbornene copolymers), styrene resins (such as syndiotactic polystyrene resins), polyacetal resins (such as polyoxymethylene), and polyester resins (polyethylene terephthalate). , Polyalkylene arylates such as polybutylene terephthalate and polyethylene naphthalate, polyarylate resins, polyglycolic acid resins, liquid crystal polyesters, etc., polycarbonate resins, polyamideimide resins, polyamide resins (aliphatic polyamide resins, aromatic polyamide resins) Etc.), polyimide resins, polyetherimide resins, polyaryl ketone resins, polyphenylene ether resins, polyphenylene sulfide resins, polysulfone resins, polyethers Sulfone resin, polyoxybenzoyl ester resin, polybenzimidazole resin, liquid crystal polymer (liquid crystalline polyester is excluded), fluororesin (polytetrafluoroethylene, etc.), may be mentioned polyether ether ketone resin.
As the thermoplastic resin, polyphenylene sulfide (PPS) resin or polyether ether ketone (PEEK) resin is preferable.

  Examples of the thermosetting resin include urea resin, melamine resin, phenol resin, resorcinol resin, epoxy resin, polyurethane, and vinyl urethane.

The synthetic resin which comprises the resin parts 20 and 120 can mix | blend a well-known fibrous filler.
As a known fibrous filler, an inorganic fibrous filler, a metallic fibrous filler, or an organic fibrous filler can be used.
These fibrous fillers can be surface-treated with an epoxy compound, an isocyanate compound, a silane compound, a titanate compound, or the like, if necessary.

Examples of the inorganic fibrous filler include carbon fiber, glass fiber, and ceramic fiber (such as silica fiber, silica / alumina fiber, zirconia fiber, boron nitride fiber, silicon nitride fiber, and potassium titanate fiber).
Examples of the metallic fibrous filler include stainless steel fiber, aluminum fiber, titanium fiber, copper fiber, and brass fiber.
Examples of organic fibrous fillers include aramid fibers, fluororesin fibers, and acrylic fibers.

  As for the compounding quantity of the fibrous filler with respect to a synthetic resin, 5-60 mass% is preferable in the total amount of a synthetic resin and a fibrous filler, and 10-50 mass% is more preferable.

When the synthetic resin constituting the resin parts 20 and 120 contains a fibrous filler, a tape made of a composite integrally formed with a thermoplastic resin in a state where the fibrous filler is oriented in one direction is used. be able to.
As such a tape, a carbon fiber tape made of a composite containing carbon fiber described in Japanese Patent No. 5592775 and an aromatic polyamide resin or an aliphatic polyamide resin, inorganic fiber described in JP 2012-86548 A ( An inorganic fiber tape made of a composite containing an olefin resin and a carbon fiber tape made of a composite containing a carbon fiber and an olefin resin described in JP2012-107189A; The organic fiber tape which consists of a composite_body | complex containing the organic fiber and olefin resin as described in 107190 gazette can be used.
Moreover, UD tape (Fiber: Carbon, Aramid, Glass, Resin: PPS, PEEK, Nylon 6, PEI, HDPE) sold by Sanwa Trading Co., Ltd. can be used.
When using the above tapes, use multiple tapes arranged side by side in the same direction and then cut into a circular shape in the thickness direction, or stacked with multiple tapes stacked at different angles. After that, it is cut into a circular shape in the thickness direction and used.

  If necessary, the synthetic resin constituting the resin parts 20 and 120 may further include colorants (dyes and pigments), lubricants, stabilizers (antioxidants, ultraviolet absorbers, heat stabilizers, light stabilizers, etc.), Antistatic agents, flame retardants, flame retardant aids, anti-blocking agents and the like can be blended.

The ultrasonic transmission / reception element 1 shown in FIGS. 1 to 3 uses a known thermoplastic resin-based adhesive, thermosetting resin-based adhesive, the first surface 11 of the piezoelectric element 10 and injection molding. It can manufacture by bonding the cyclic | annular plane part 21 of the resin part 20 obtained by the method.
The ultrasonic transmitting / receiving element 1 shown in FIG. 1 to FIG. 3 has an annular plane portion of the resin portion 20 on each of the second surface 12 opposite to the first surface 11 of the plate-like piezoelectric element 10 in FIG. The thing to which 21 was fixed is also included.
The same applies to the ultrasonic transmitting / receiving element 100 shown in FIG.

Next, the operation of the ultrasonic transmitting / receiving element 1 shown in FIG. 1 will be described.
When an alternating current is applied to the piezoelectric element 10 and a voltage is applied, the piezoelectric element 10 is repeatedly expanded and contracted in the surface direction (diameter direction).
The resin part 20 vibrates in the thickness direction (vertical direction) in response to vibrations caused by expansion and contraction of the piezoelectric element 10 in the diameter direction. The vertical vibration is amplified by the dome 22 and transmitted as an ultrasonic wave.
Conversely, when receiving ultrasonic waves, the resin portion 20 (dome portion 22) receives vibrations from the ultrasonic waves and vibrates in the vertical direction, and the piezoelectric element 10 receiving the vibrations expands and contracts in the diameter direction. Then, since the piezoelectric element 10 generates electric energy by the expansion and contraction, it is possible to detect ultrasonic waves.

(2) Ultrasonic Transceiver Element Shown in FIG. 5 An embodiment different from the ultrasonic transceiver element 1 in FIGS. 1 to 4 will be described with reference to FIG.
The transmitting / receiving apparatuses 200 and 300 shown in FIG. 5 have the same material, d2 / d1, h1 / d1, t1 / d1, and A2 / A1 as the transmitting / receiving apparatus 1 shown in FIGS. is there.
In the embodiment where the planar shape is rectangular, d1 is the length of the long side, and in the embodiment where the planar shape is a pentagon or more polygon, d1 is the length of the maximum diameter (maximum diagonal), and the planar shape is an elliptical embodiment. Then, d1 is the length of the major axis.

The transmission / reception element 200 shown in FIGS. 5A and 5B is the same as the transmission / reception element 1 shown in FIGS. 1 and 2 except that the planar shape is different.
The ultrasonic transmitting / receiving element 200 shown in FIGS. 5A and 5B includes a plate-like piezoelectric element 210 and a resin portion 220, and both the plate-like piezoelectric element 210 and the resin portion 220 are planar. The shape is square.

The resin part 220 has an annular flat part 221 and a dome part 222 formed inside the annular flat part 221.
In the embodiment shown in FIGS. 5A and 5B, only the annular flat surface portion 221 of the resin portion 220 is fixed to the first surface 211 of the plate-like piezoelectric element 210, and the first surface 211 and the dome are fixed. An internal space 215 is formed between the portions 222.

  5A and 5B show an embodiment in which the internal space 215 of the dome portion 222 is a sealed space, but the dome portion 222 has an opening as shown in FIG. 3B. In addition, the internal space 215 of the dome portion 222 may not be hermetically sealed but may be in the embodiment communicated with the outside.

In the embodiment of the transmitting / receiving element 300 shown in FIG. 5C, the resin part 320 has a substrate part (square substrate part) 321 and a dome part 322 formed on the substrate part 321.
In the embodiment shown in FIG. 5C, the entire surface of the substrate portion 321 of the resin portion 320 is fixed to the first surface 311 of the plate-like piezoelectric element 310, and between the substrate portion 321 and the dome portion 322. An internal space 35 is formed.
The transmission / reception element 300 of the embodiment shown in FIG. 5C may have a sealed internal space as shown in FIG. 3A, or an opening as shown in FIG. It may have an internal space.
The transmission / reception elements 200 and 300 shown in FIGS. 5A to 5C operate in the same manner as the transmission / reception apparatus 1 shown in FIGS.

Since the transmission / reception element of the present invention is composed of a combination of a piezoelectric element and a resin part, it can be reduced in size and weight, and rust is generated, as compared with the one using metal as in Patent Document 1. There is no problem of electrical insulation, and there is electrical insulation. Furthermore, compared with what uses the ceramics of patent document 2, durability is also high.
The transmitter / receiver device of the present invention is suitable for use in a high humidity atmosphere or in a state where electrical insulation is required, and in addition, acid gas including acid and alkali, active volcanoes, etc. It is also suitable for use in applications where ultrasonic waves are transmitted in a situation where metal is corroded, such as in a spraying place.

The ultrasonic transmission / reception apparatus of the present invention includes the above-described ultrasonic transmission / reception element.
The ultrasonic transmission / reception apparatus of the present invention can be a phased array type ultrasonic transmission / reception apparatus in which a number of the above-described ultrasonic transmission / reception elements are combined.
When using a phased array type ultrasonic transmission / reception device, for example, when using ultrasonic transmission / reception elements having a planar shape of a circle, quadrangle, hexagon, etc. When an ultrasonic wave transmitting / receiving element having a rectangular shape is used, for example, a large number of transmitting / receiving apparatuses can be arranged in parallel.
In addition, when an ultrasonic transmission / reception element having a quadrangular (preferably rectangular) planar shape is used, a large number of transmission / reception devices can be arranged in parallel.

Example 1 and Comparative Example 1
Transceiver elements made of the materials shown in Table 1 were manufactured.
Example 1 and Comparative Example 1 have the same shape and the same size except that the materials are different.
The resin part of Example 1 was obtained by injection molding.
The piezoelectric element and resin part (PPS) of Example 1 and the piezoelectric element and aluminum of Comparative Example 1 were all bonded with the same amount of “Araldite Standard” manufactured by Huntsman Japan Co., Ltd.

(Piezoelectric element 10)
Material: PZT (Fuji Ceramics Corporation C213)
Outer diameter: 10mm
Thickness: 1mm
(Resin part 20 [Comparative Example 1 is aluminum])
Outer diameter (outer diameter of the annular flat surface) d1: 10 mm
Dome outer diameter d2: 6 mm
Dome height h1: 2 mm
Thickness: 1mm
PPS: Polyplastics Durafide 2130A1

Using the transmitting and receiving elements of Example 1 and Comparative Example 1, the sound pressure was measured by the apparatus shown in FIG.
The first fixed base 50 and the second fixed base 51 were placed on the flat floor surface 40, the transmitting / receiving element 1 was fixed to the first fixed base 50, and the microphone 60 was fixed to the second fixed base 51.
The distance between the transmitting / receiving element 1 and the microphone 60 was 1 m, and both were fixed at a height of 1 m from the floor surface 40. It was confirmed in advance that there was no acoustic reflection from the floor surface 40.
The ultrasonic wave transmitted when the transmitting / receiving element 1 was energized was measured by the microphone 60 as sound pressure.

In Example 1, the resonance frequency was confirmed after soldering the electrode having the lead wire connected to the piezoelectric element (PZT), and the resonance point was confirmed at 39 kHz and 61 kHz.
When voltage was gradually applied at 39 kHz, the maximum point of sound pressure was 1.08 Pa, and the current and voltage at that time were 51 mA and 11 V.
A voltage was gradually applied at 61 kHz, the maximum point of sound pressure was 0.08 Pa, and the current and voltage at that time were 40 mA and 15 V.

In Comparative Example 1, the resonance frequency was confirmed after soldering the electrode having the lead wire connected to the piezoelectric element (PZT), and the resonance point was confirmed at 34 kHz and 98 kHz.
A voltage was gradually applied at 34 kHz, the maximum point of sound pressure was 0.03 Pa, and the current and voltage at that time were 25 mA and 12 V.
A voltage was gradually applied at 98 kHz, the maximum point of sound pressure was 0.08 Pa, and the current and voltage at that time were 128 mA and 15 V.
In Comparative Example 1, compared with Example 1, a high sound pressure was not obtained at any frequency.
The difference in resonance point between the element 1 of Example 1 and Comparative Example 1 is due to the difference in the constituent materials of Example 1 (PPS) and Comparative Example 1 (aluminum).

The ultrasonic transmission / reception element and the ultrasonic transmission / reception device using the ultrasonic transmission / reception element of the present invention can be used as a means for measuring an accurate distance to the object to be measured, as well as a security sensor and an obstacle for an automobile. Various obstacle detection sensors such as detection sensors, sensors for automatic hand washing machines, various human detection sensors such as automatic door sensors, various object movement detection sensors for automobile car wash machines, etc., car detection sensors for level crossings, sensors for parking lot management systems , Golf cart collision prevention sensor, monorail vehicle collision prevention sensor, helicopter obstacle detection sensor, unmanned medicine spray sensor on fruit trees, spot cooler human tracking sensor, conveyor object detection sensor, bather safety monitoring sensor Can be used for etc.
Furthermore, as other uses, it can be used as a repelling device for small animals such as mice indoors and outdoors, and as a repelling device for birds outdoors.

DESCRIPTION OF SYMBOLS 1,100 Transceiving element 10,110 Piezoelectric element 15,115 Internal space 20,120 Resin part 21,121 Annular flat plate part 22,122 Dome part

Claims (9)

A plate-shaped piezoelectric element comprising a piezoelectric ceramic element, an ultrasonic transmitting and receiving device having a resin portion which is fixed directly on at least one surface of the piezoelectric ceramic element consists of a plate-shaped piezoelectric element,
The resin part is fixed so as to form an internal space surrounded by the resin part and the plate-like piezoelectric element,
An ultrasonic transmission / reception element, wherein the internal space is a sealed space. A plate-shaped piezoelectric element comprising a piezoelectric ceramic element, an ultrasonic transmitting and receiving device having a resin portion which is fixed directly on at least one surface of the piezoelectric ceramic element consists of a plate-shaped piezoelectric element,
The resin part is fixed so as to form an internal space surrounded by the resin part and the plate-like piezoelectric element,
The ultrasonic transmission / reception element, wherein the resin part has an opening, and the internal space communicates with the outside.   The said resin part has a dome part formed inside the annular plane part and the said annular plane part, and the space is formed inside the said dome part, The Claim 1 or 2 Ultrasonic transmitter / receiver element. Each of the planar shapes of the piezoelectric element and the resin portion is circular, elliptical or polygonal,
The ultrasonic transmission / reception element according to claim 1 or 2, wherein a projected area (A1) of the piezoelectric element and a projected area (A2) of the resin portion satisfy A1≤A2. Each of the planar shapes of the piezoelectric element and the resin portion is circular, elliptical, or polygonal,
The projected area (A1) of the piezoelectric element and the projected area (A2) of the resin part are A1 ≦ A2.
The ratio (d2 / d1) of the outer diameter (d1) of the annular flat portion of the resin portion to the outer diameter (d2) of the dome portion of the resin portion is 0.4 to 0.8. Ultrasonic transmitter / receiver element. Each of the planar shapes of the piezoelectric element and the resin portion is circular, elliptical, or polygonal,
The projected area (A1) of the piezoelectric element and the projected area (A2) of the resin part are A1 ≦ A2.
The ratio (h1 / d1) of the outer diameter (d1) of the annular flat portion of the resin portion to the height (h1) of the apex of the dome portion of the resin portion from the first surface of the piezoelectric element is 0.05 to The ultrasonic transmission / reception element according to claim 1 or 2, which is 0.3.   The ultrasonic transmission / reception according to claim 1 or 2, wherein the piezoelectric element is made of a piezoelectric ceramic element, and the resin portion is made of polyphenylene sulfide (PPS) resin or polyether ether ketone (PEEK) resin. element.   The ultrasonic transmitting / receiving element according to claim 1, wherein the resin portion contains a fibrous filler.   An ultrasonic transmission / reception apparatus comprising the ultrasonic transmission / reception element according to claim 1.

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