WO2014171158A1

WO2014171158A1 - Ultrasonic sensor and method for producing same

Info

Publication number: WO2014171158A1
Application number: PCT/JP2014/050963
Authority: WO
Inventors: 真弓松藤; スパナンカンライ; 卓松本
Original assignee: 株式会社村田製作所
Priority date: 2013-04-19
Filing date: 2014-01-20
Publication date: 2014-10-23
Also published as: CN104335604B; JP5660257B1; CN104335604A; JPWO2014171158A1

Abstract

An ultrasonic sensor equipped with: a damper (40) provided with a first recess (43) and second recesses (44A, 44B); an internal wiring member (50) having one end connected to a piezoelectric element and the other end (52) positioned inside the first recess (43); and an external wiring member (60) having insertion parts (62A, 62B) which are positioned, respectively, inside the second recesses (44A, 44B). Consequently, it is possible to suppress the occurrence of a joining failure between the internal wiring member and the external wiring member.

Description

Ultrasonic sensor and manufacturing method thereof

The present invention relates to an ultrasonic sensor and a method for manufacturing the same, and more particularly, an ultrasonic sensor in which an internal wiring member that supplies power to a piezoelectric element is provided in a case, and an external wiring member is electrically connected to the internal wiring member, and the ultrasonic sensor It relates to a manufacturing method.

The ultrasonic sensor detects an object by intermittently transmitting an ultrasonic pulse signal and receiving a reflected wave from the object. A general ultrasonic sensor includes a piezoelectric element, a case that accommodates the piezoelectric element, and a wiring member that is connected to the piezoelectric element and is drawn out of the case. The wiring member may be composed of one member, or may be composed of two members, an internal wiring member and an external wiring member that are electrically connected to each other.

Japanese Unexamined Patent Publication No. 2011-250327 (Patent Document 1) discloses an ultrasonic sensor. In this publication, the structure of the soldering part can be easily formed by connecting the terminals of the conductive member and the electrodes of the piezoelectric element using solder, and covering the periphery of the solder with a resin, and the scattering of solder particles. It can be prevented.

Japanese Unexamined Patent Application Publication No. 2012-010312 (Patent Document 2) also discloses an ultrasonic sensor. This ultrasonic sensor includes a case for accommodating a piezoelectric element. The side wall portion of the case has a thin portion on the opening side and a thick portion on the bottom side. An elastic member is provided between the thick part and the terminal holding member. This publication states that this configuration can prevent vibration leakage and improve reverberation characteristics due to vibration leakage.

Japanese Patent Laid-Open No. 04-220900 (Patent Document 3) discloses a drip-proof ultrasonic microphone. The publication states that the use of anti-vibration rubber increases the detection sensitivity of the received signal and improves the detection performance at short distances.

JP 2011-250327 A JP 2012-010312 A Japanese Unexamined Patent Publication No. 04-220900

The internal wiring member is connected to the piezoelectric element arranged in the case, and the internal wiring member and the external wiring member are joined using solder or the like. In an ultrasonic sensor having such a structure, poor bonding is likely to occur between the internal wiring member and the external wiring member.

An object of the present invention is to obtain an ultrasonic sensor having a structure capable of suppressing the occurrence of poor bonding between an internal wiring member and an external wiring member, and a manufacturing method thereof.

An ultrasonic sensor according to the present invention includes a bottomed cylindrical case, a piezoelectric element provided on the inner bottom surface of the case, and a side opposite to the side facing the piezoelectric element disposed in the case. A damper having a main surface on which the first concave portion and the second concave portion are provided on the main surface, and one end connected to the piezoelectric element, from the side where the piezoelectric element is located to the first concave side The other end of the internal wiring member disposed in the first recess and an insertion portion, the insertion portion being disposed in the second recess, and through the opening of the case. An external wiring member drawn out of the case, wherein the internal wiring member and the external wiring member have the other end of the internal wiring member inserted into the first recess and the external wiring member. The plug is inserted into the second recess and The first concave portion has an inner wall portion facing from the side where the second concave portion is located with respect to the other end of the internal wiring member disposed in the first concave portion. .

Preferably, when the first concave portion and the second concave portion are viewed in a plan view from the normal direction to the bottom surface of the case, a portion of the second concave portion that is farthest when viewed from the first concave portion is a reference position. Then, the inner wall portion is formed so as to be positioned between the reference position and the internal wiring member.

Preferably, the damper further includes a lead-out portion provided so as to lead out the internal wiring member along an arbitrary path. Preferably, the lead-out portion is recessed toward the inside of the damper. The internal wiring member has a portion disposed in the guide portion.

Preferably, the lead-out portion includes a bulge portion provided so as to bulge from the main surface toward a side where the opening of the case is located, and the first concave portion is located from the bulge portion. And a pair of projecting portions provided so as to project toward the side, and the external wiring member has a portion disposed between the pair of projecting portions.

Preferably, the internal wiring member has an extending portion disposed on the first concave portion side when viewed from the protruding portion.

Preferably, the main surface is provided with the two second recesses, and the external wiring member has the two insertion portions respectively disposed in the two second recesses. The two second recesses are formed so as to communicate with the first recess.

Preferably, a portion of the external wiring member that is electrically connected to the internal wiring member and a portion of the internal wiring member that is electrically connected to the external wiring member are a bottom surface of the case. Extending in the same direction along the normal direction to the.

Preferably, an adhesive that adheres the internal wiring member to the damper is further provided.
Preferably, a fixing member attached in contact with the damper is further provided, and the fixing member presses the external wiring member against the internal wiring member.

An ultrasonic sensor manufacturing method according to the present invention includes a bottomed cylindrical case, a piezoelectric element provided on the inner bottom surface of the case, a side disposed in the case and facing the piezoelectric element, Has a main surface on the opposite side, the damper having the first concave portion and the second concave portion provided on the main surface, one end connected to the piezoelectric element, and the first element from the side where the piezoelectric element is located. An internal wiring member that is pulled out toward the side of the recess, the other end of which is disposed in the first recess, and an insertion portion; the insertion portion is disposed in the second recess; An external wiring member drawn out of the case through the opening, wherein the first recess is positioned with respect to the other end of the internal wiring member disposed in the first recess. Of the ultrasonic sensor having an inner wall portion facing from the side in which it is The manufacturing method includes a step of holding the internal wiring member in the first recess by inserting the other end of the internal wiring member into the first recess, and a step of Inserting the insertion part into the second recess to hold the external wiring member in the second recess, and electrically connecting the internal wiring member and the external wiring member to each other; Have

According to the present invention, it is possible to obtain an ultrasonic sensor having a structure capable of suppressing the occurrence of poor bonding between the internal wiring member and the external wiring member, and a manufacturing method thereof.

It is sectional drawing which shows the ultrasonic sensor in embodiment. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. It is a 1st perspective view which shows the ultrasonic sensor in embodiment. It is a 2nd perspective view which shows the ultrasonic sensor in embodiment. It is a perspective view which shows the state which the ultrasonic sensor in embodiment decomposed | disassembled. It is a perspective view which shows the piezoelectric element and internal wiring member with which the ultrasonic sensor in embodiment is equipped. It is a 1st perspective view which shows the damper with which the ultrasonic sensor in embodiment is equipped. It is a 2nd perspective view which shows the damper with which the ultrasonic sensor in embodiment is equipped. It is a top view which shows the damper with which the ultrasonic sensor in embodiment is equipped. It is a perspective view which shows typically the vicinity of the main surface of the damper with which the ultrasonic sensor in an embodiment is provided. It is a 1st perspective view which shows the 1st process of the manufacturing method of the ultrasonic sensor in embodiment. It is a 2nd perspective view which shows the 1st process of the manufacturing method of the ultrasonic sensor in embodiment. It is a 1st perspective view which shows the 2nd process of the manufacturing method of the ultrasonic sensor in embodiment. It is a 2nd perspective view which shows the 2nd process of the manufacturing method of the ultrasonic sensor in embodiment. It is a perspective view which shows the damper with which the ultrasonic sensor in the 1st modification of embodiment is equipped. It is sectional drawing which shows the ultrasonic sensor in the 1st modification of embodiment. It is sectional drawing which shows the ultrasonic sensor in the 2nd modification of embodiment. It is a perspective view which shows the ultrasonic sensor in the 3rd modification of embodiment. It is a top view which shows the damper with which the ultrasonic sensor in the 4th modification of embodiment is equipped. It is a top view which shows the damper with which the ultrasonic sensor in the 5th modification of embodiment is equipped. It is a perspective view which shows the damper with which the ultrasonic sensor in the 6th modification of embodiment is equipped.

Embodiments and modifications based on the present invention will be described below with reference to the drawings. In the description of the embodiments and the modifications, when referring to the number and amount, the scope of the present invention is not necessarily limited to the number and amount unless otherwise specified. In the description of the embodiments and the modifications, the same reference numerals are assigned to the same parts and corresponding parts, and the repeated description may not be repeated.

[Embodiment]
(Ultrasonic sensor 100)
The ultrasonic sensor 100 according to the embodiment will be described with reference to FIGS. FIG. 1 is a cross-sectional view showing an ultrasonic sensor 100. 2 is a cross-sectional view taken along the line II-II in FIG. 3 and 4 are first and second perspective views showing the ultrasonic sensor 100, respectively. FIG. 5 is a perspective view showing the ultrasonic sensor 100 in an exploded state.

1 to 5, the ultrasonic sensor 100 includes a case 10, a piezoelectric element 20 (FIGS. 1, 2 and 5), a reinforcing member 30, a damper 40, an internal wiring member 50, an external wiring member 60, And a damping material 70 (FIGS. 1 and 2). 3 to 5, the damping material 70 is not shown in order to clearly represent the internal structure of the case 10 and the like. 5 and 7 show the Z-axis direction, the Z1 direction (FIG. 7), the Y-axis direction, and the X-axis direction. Although details of each part will be described later, the Z-axis direction indicates a normal direction to the bottom plate surface of the case 10 (corresponding to the “bottom surface” of the present invention). The Z1 direction indicates a direction from the upper end 12 side to the lower end 11 side of the case 10 in the Z-axis direction. The Y-axis direction indicates the extending direction of the first recess 43. The X-axis direction indicates a direction perpendicular to the Z-axis direction and the Y-axis direction. These are the same in FIGS. 9, 10, 15, and 18 to 21 described later.

(Case 10)
The case 10 includes a disc-shaped bottom plate and a cylindrical side wall provided along the periphery of the bottom plate. The case 10 has a bottomed cylindrical shape in which the lower end 11 side is closed and the upper end 12 side is open. The inner surface of the bottom plate is an inner bottom surface 13 (FIGS. 1, 2, and 5). On the inner bottom surface 13, a pedestal 14 (FIG. 5) for arranging the reinforcing material 30 is provided. The case 10 is made of, for example, aluminum having high elasticity and light weight. The case 10 is manufactured by forging or cutting such aluminum.

(Piezoelectric element 20)
FIG. 6 is a perspective view showing the piezoelectric element 20 and the internal wiring member 50. 5 and 6, the piezoelectric element 20 is made of, for example, lead zirconate titanate ceramic. The piezoelectric element 20 is disposed on the inner bottom surface 13 (FIG. 5) of the case 10 and is fixed to the inner bottom surface 13 using an adhesive or the like (not shown). The piezoelectric element 20 has a flat plate shape, and drive electrode pairs are provided on both flat plate surfaces. Specifically, the first drive electrode 21 (FIG. 6) and a part of the second drive electrode 22 (FIG. 6) are provided on the flat plate surface of the piezoelectric element 20 opposite to the case 10. . The first drive electrode 21 has a rectangular shape. The second drive electrode 22 has a shape extending from the flat plate surface on the case 10 side of the piezoelectric element 20 to the flat plate surface on the opposite side. A gap 23 is provided between the first drive electrode 21 and the second drive electrode 22. The piezoelectric element 20 spreads in the radial direction and vibrates when a drive voltage is applied to the drive electrode pair. The piezoelectric element 20 and the bottom plate of the case 10 can function as a bimorph vibrator. The bimorph vibrator bends and vibrates in the normal direction of the flat plate surface of the piezoelectric element 20 by spreading vibration of the piezoelectric element 20. Due to this bending vibration, the inner bottom surface 13 of the case 10 forms a main vibration region of the case 10.

(Reinforcing material 30)
The reinforcing member 30 has a disk shape, and an opening is provided at the center. The reinforcing material 30 functions as a so-called weight. The reinforcing member 30 is produced, for example, by press molding so as to have a high acoustic impedance. The reinforcing material 30 is made of, for example, SUS and zinc, which are materials having higher density and rigidity than the case 10. The reinforcing material 30 may be made of the same material (aluminum) as the case 10 by adjusting the size (thickness, etc.) and shape.

The reinforcing material 30 is disposed in contact with the pedestal 14 of the case 10 (see arrow AR30 in FIG. 5). By providing the reinforcing member 30, the rigidity of the peripheral portion of the inner bottom surface 13 of the case 10 can be increased, and the vibration in the bottom plate of the case 10 can be suppressed from being transmitted to the side wall of the case 10. Since the reinforcing material 30 is not an essential configuration, it is provided as necessary.

(Damper 40)
The damper 40 is disposed in the case 10. The damper 40 (also referred to as a buffer material) is, for example, a molded body having high elasticity. The damper 40 is made of, for example, silicone rubber or urethane resin. A convex portion 41 (see FIGS. 1, 2, and 8) is provided at the lower portion of the damper 40. The damper 40 is disposed in the case 10 so that the convex portion 41 engages with the opening of the reinforcing member 30 (see arrow AR40 in FIG. 5).

As shown in FIG. 1 and FIG. 2, in the present embodiment, the convex portion 41 and the piezoelectric element 20 are spaced apart from each other. The convex portion 41 and the piezoelectric element 20 may be in contact with each other. A sound absorbing material such as polyester felt may be provided between the convex portion 41 and the piezoelectric element 20. By using the sound absorbing material, it is possible to absorb sound waves that are about to escape from the piezoelectric element 20 to the opening side of the case 10. In the present embodiment, the damper 40 is not in contact with the side wall of the case 10. The damper 40 may have a shape that contacts the side wall of the case 10.

7 and 8 are first and second perspective views showing the damper 40, respectively. In addition to the convex portion 41 (FIG. 8), the damper 40 includes a main surface 42, a first concave portion 43, a pair of second

concave portions

44A and 44B, bulging

portions

45A and 45B, a columnar portion 45C, and guide

portions

46 and 47. have. In FIG. 7, a part of the columnar portion 45 C is shown broken away in order to clearly represent the first concave portion 43 and the second concave portions 44 A and 44 B. The

guide portions

46 and 47 correspond to the “lead-out portion” of the present invention.

The main surface 42 of the damper 40 is a part of a flat plate surface formed in a disk shape among the parts constituting the damper 40. In a state where the damper 40 is disposed in the case 10, the main surface 42 is located on the side opposite to the side facing the piezoelectric element 20 when viewed in plan from the Y-axis direction. The bulging

portions

45A and 45B and the columnar portion 45C are provided such that a part of the main surface 42 bulges from the main surface 42 toward the side where the opening of the case 10 is located (the upper end 12 side). It has been. The bulging

portions

45A and 45B and the columnar portion 45C are provided along a part of the outer periphery of the damper 40, and are provided apart from each other.

The bulging

portions

45A and 45B have a columnar shape. The guide part 46 is provided between the bulging part 45A and the bulging part 45B. The guide portion 46 has a shape that is recessed from the upper end surfaces of the bulging

portions

45A and 45B toward the convex portion 41 side. The bulging

portions

45A and 45B and the guide portion 46 are arranged in a straight line. The guide part 47 is provided so as to cut out a part of the disk-shaped part of the part constituting the damper 40. In other words, the guide portion 47 is formed so as to be recessed from the outer periphery of the damper 40 toward the inside in the radial direction. A space (groove shape) having an L shape for arranging the internal wiring member 50 is formed by the guide portion 46 and the guide portion 47.

The first recess 43 and the

second recesses

44A and 44B are provided on the main surface 42. When the damper 40 is viewed in plan from the location where the bulging

portions

45A and 45B and the guide portion 46 are formed, the first concave portion 43 and the second

concave portions

44A and 44B are on the side where the guide portion 47 is provided. Is on the opposite side. The first concave portion 43 and the second

concave portions

44A and 44B are formed such that a part of the main surface 42 is recessed toward the convex portion 41 side.

The first concave portion 43 is provided along the end surfaces 45S of the bulging

portions

45A and 45B, and forms a rectangular parallelepiped space (accommodating space). The first concave portion 43 extends along the same direction (Y-axis direction in FIG. 7) as the direction in which the bulging

portions

45A and 45B and the guide portion 46 are arranged. When viewed in the Z-axis direction, the first recess 43 extends along a direction (Z1 direction in FIG. 7) from the upper end 12 side to the lower end 11 side of the case 10 (FIG. 3 and the like). Although details will be described later, a part (the other end 52) of the internal wiring member 50 is disposed in the first recess 43.

The

second recesses

44A and 44B are formed so as to cut out part of the inner peripheral surface of the first recess 43, and are spaced from each other in the direction in which the first recess 43 extends (Y-axis direction in FIG. 7). Are lined up. When viewed in the Z-axis direction, the

second recesses

44A and 44B also extend along the direction from the upper end 12 side to the lower end 11 side (Z1 direction in FIG. 7) of the case 10 (FIG. 3 and the like). The

second recesses

44A and 44B form a space (accommodating space) having a shape in which a cylinder is halved along the axial direction. Although details will be described later, the tip 62A (insertion portion) of the pin terminal 61A of the external wiring member 60 is disposed in the second recess 44A. In the second recess 44B, the tip 62B (insertion portion) of the pin terminal 61B of the external wiring member 60 is disposed.

(Internal wiring member 50)
The internal wiring member 50 (see FIG. 5) includes one end 51 and the other end 52, and has a strip shape. The internal wiring member 50 has a function of supplying a driving voltage from an external wiring member 60 described later to the piezoelectric element 20. As the internal wiring member 50, for example, a flexible printed circuit is used. As shown in FIG. 6, a plurality of wiring patterns (first wiring 57 and second wiring 58) are formed on the flat surface of the internal wiring member 50 on the piezoelectric element 20 side.

One end 51 of the internal wiring member 50 is electrically connected to the piezoelectric element 20. Specifically, the first wiring 57 of the internal wiring member 50 is electrically connected to the first drive electrode 21 of the piezoelectric element 20. The second wiring 58 of the internal wiring member 50 is electrically connected to the second drive electrode 22 of the piezoelectric element 20. A midway portion 53 between the one end 51 and the other end 52 is drawn from the side where the piezoelectric element 20 is located toward the main surface 42 (first recess 43). The midway portion 53 is bent or curved along the surface in the

guide portions

46 and 47 and is disposed so as to pass through the

guide portions

46 and 47.

The portion on the other end 52 side of the internal wiring member 50 has a T-shape. The other end 52 of the internal wiring member 50 includes extending

portions

52A and 52B (FIG. 5). The extending

portions

52A and 52B have a shape extending in a direction (Y-axis direction in FIG. 5) orthogonal to a direction (X-axis direction in FIG. 5) in which the intermediate portion 53 extends. The portion on the other end 52 side of the internal wiring member 50 is inserted into the first recess 43 (see arrow AR50 in FIGS. 5 and 7). Here, the first recess 43 has an inner wall portion 43 C that faces the other end 52 of the internal wiring member 50 disposed in the first recess 43 from the side where the second recesses 44 A and 44 B are located. . Since the other end 52 of the internal wiring member 50 has the elastic force (restoring force) of the intermediate portion 53 of the internal wiring member 50, when the other end 52 of the internal wiring member 50 is inserted into the first recess 43. The tip ends 62A and 62B of the

pin terminals

61A and 61B are sandwiched between the other end 52 of the internal wiring member 50 and the inner peripheral wall of the

second recesses

44A and 44B, and are locked by the inner wall portion 43C of the first recess 43. . The first recess 43 has a distance in the X-axis direction of the first recess 43 so that there is a slight margin between the inner wall 43C and the other end 52 of the internal wiring member 50 after locking. It may be formed so as to be longer than the thickness.

The internal wiring member 50 is arranged so that the other end 52 faces the same direction as the

pin terminals

61A and 61B of the external wiring member 60 (Z1 direction in FIG. 7), and is wired to the

pin terminals

61A and 61B in that state. . In other words, a portion (

pin terminals

61A and 61B) electrically connected to the internal wiring member 50 in the external wiring member 60 and a portion electrically connected to the external wiring member 60 in the internal wiring member 50. The (other end 52) extends in the same direction along the direction (Z1 direction) from the upper end 12 side to the lower end 11 side of the case 10.

(External wiring member 60)
The external wiring member 60 (see FIG. 5) includes

pin terminals

61A and 61B and a holding portion 65. The

pin terminals

61A and 61B have a columnar shape, and a driving voltage is applied from the outside. The holding portion 65 has, for example, a rectangular parallelepiped shape and is made of a resin such as nylon 66. The

pin terminals

61A and 61B are held by the holding unit 65 in parallel with a gap therebetween. The interval between the second recess 44A and the second recess 44B corresponds to the interval between the pin terminal 61A and the pin terminal 61B. The tips of the

pin terminals

61A and 61B function as the

insertion portions

62A and 62B.

The insertion part 62A of the pin terminal 61A is disposed in the second recess 44A (see arrow AR62A in FIG. 7). The insertion portion 62B of the pin terminal 61B is disposed in the second recess 44B (see arrow AR62B in FIG. 7). A portion of the external wiring member 60 on the holding portion 65 side is drawn out of the case 10 through the opening of the case 10. In a state where the insertion portion 62A of the pin terminal 61A is disposed in the second recess 44A and the insertion portion 62B of the pin terminal 61A is disposed in the second recess 44B, the

pin terminals

61A and 61B are the bottom surfaces of the case 10. Extends along the direction normal to (parallel to the Z-axis direction). In this state, the pin terminals 61 A and 61 B are opposed to the other end 52 of the internal wiring member 50. More specifically, the pin terminal 61A is opposed to the first wiring 57 (FIG. 6) at the other end 52 of the internal wiring member 50, and the pin terminal 61B is the second wiring 58 at the other end 52 of the internal wiring member 50. (FIG. 6).

Solders

65A and 65B (FIGS. 2 to 4) are provided in the first recess 43 and the

second recesses

44A and 44B, respectively, whereby the first wiring 57 at the pin terminal 61A and the other end 52 of the internal wiring member 50 is provided. (FIG. 6) is electrically connected, and the pin terminal 61B and the second wiring 58 (FIG. 6) at the other end 52 of the internal wiring member 50 are electrically connected. That is, electrical connection between the piezoelectric element 20 and the external wiring member 60 is ensured through the internal wiring member 50.

(Damping material 70)
The damping material 70 (FIGS. 1 and 2) is filled in the case 10 and seals the damper 40, the

tips

62 A and 62 B of the

pin terminals

61 A and 61 B, and the internal wiring member 50. The space on the inner bottom surface 13 side of the case 10 is covered with the reinforcing material 30 and the damper 40. The damping material 70 is filled only in the space on the opening side of the case 10. The damping material 70 also has a function of making it difficult for the damper 40 to come out of the case 10. Examples of the material of the damping material 70 include a silicone resin and a urethane resin. The vibration of the case 10 is attenuated by the damper 40 and the damping material 70. The vibration of the case 10 hardly propagates to the external wiring member 60. Vibration leakage that occurs when the

pin terminals

61A and 61B are mounted on an external substrate is effectively reduced.

As the material of the damper 40, a material that is difficult to propagate vibrations may be selected. As a material for the damping material 70, a material that suppresses (damps) the vibration of the case 10 may be selected.

The

pin terminals

61A and 61B and the piezoelectric element 20 are wired by the internal wiring member 50. Since the FPC is employed for the internal wiring member 50, even if an external force is repeatedly applied to the

pin terminals

61A and 61B, the internal wiring member 50 is elastically deformed each time the external force is applied. Therefore, the occurrence of disconnection as in the case where a lead wire is employed for the internal wiring member 50 is suppressed. Furthermore, since the internal wiring member 50 has a belt-like shape and has a larger contact area with the damping material 70 than the lead wire, the damping material 70 is not subjected to local load, and the damping material 70 Destroying 70 is also suppressed.

The other end 52 of the internal wiring member 50 and the

tips

62A and 62B (insertion portions) of the

pin terminals

61A and 61B face in the same direction, and these are connected using

solders

65A and 65B. The intermediate portion 53 of the internal wiring member 50 is bent or curved with a certain curvature by being pulled out in the radial direction of the case 10 from the connection portion with the

pin terminals

61A and 61B. If an external force in the direction of pulling out from the case 10 is applied to the

pin terminals

61A and 61B, a force in the same direction as the external force is applied to the connection portion between the internal wiring member 50 and the

pin terminals

61A and 61B. When the midway portion 53 of the internal wiring member 50 is bent, the curvature of the internal wiring member 50 changes. At this time, the shear stress acting on the connection portion between the internal wiring member 50 and the pin terminals 61 A and 61 B is canceled (reduced) by the spring elasticity of the internal wiring member 50. A configuration in which disconnection at the connecting portion between the pin terminals 61 A and 61 B and the internal wiring member 50 hardly occurs is realized.

FIG. 9 is a plan view showing the damper 40. FIG. 10 is a perspective view schematically showing the vicinity of the main surface 42 of the damper 40. Referring to FIGS. 9 and 10, first recess 43 of the present embodiment includes

side wall portions

43A and 43B, an inner wall portion 43C and a bottom surface portion 43D (FIG. 10). The

side wall portions

43A and 43B are opposed to each other with a space therebetween. The

side wall portions

43A and 43B are portions located on both outer sides in the Y-axis direction when viewed from the inner wall portion 43C. The first concave portion 43 is formed as a space surrounded by the

side wall portions

43A and 43B, the inner wall portion 43C, the bottom surface portion 43D, and the end surfaces 45S (see FIGS. 7 and 9) of the bulging

portions

45A and 45B.

In the state where the other end 52 (FIG. 10) of the internal wiring member 50 is disposed in the first recess 43, the inner wall portion 43 C has the second recesses 44 A and 44 B positioned with respect to the other end 52 of the internal wiring member 50. Opposite from the side. In FIG. 10, for convenience, a portion corresponding to the inner wall portion 43 C is represented using hatched hatching. As shown in FIG. 9, when the first recess 43 and the

second recesses

44A and 44B are viewed in a plan view from the normal direction to the bottom surface of the case 10, the farthest when viewed from the first recess 43 of the

second recesses

44A and 44B. If the portions located at the reference positions PA and PB are the reference positions PA and PB, the inner wall portion 43C is formed between the reference positions PA and PB and the internal wiring member 50.

(Production method)
A method for manufacturing the ultrasonic sensor 100 will be described with reference to FIGS. First, the piezoelectric element 20 (see FIG. 1 and the like) and the reinforcing material 30 are arranged in the case 10. One end 51 (see FIG. 1 and the like) of the internal wiring member 50 is connected to the piezoelectric element 20, and the internal wiring member 50 is pulled out toward the opening side of the case 10. As the damper 40 is disposed in the case 10, the internal wiring member 50 is disposed in the

guide portions

47 and 46 so as to pass through the

guide portions

47 and 46 of the damper 40 in order. The other end 52 of the internal wiring member 50 is curved as shown by an arrow DR1 in FIGS. 11 and 12 and is inserted into the first recess 43 of the damper 40. In this state, the other end 52 of the internal wiring member 50 is locked to the inner wall portion 43 C (FIG. 10 or the like) of the first recess 43 by the action of the elastic force (restoring force) of the midway portion 53 of the internal wiring member 50. Yes. That is, the other end 52 of the internal wiring member 50 is held while being positioned by the first recess 43.

Referring to FIGS. 13 and 14, next, external wiring member 60 is prepared, and tips 62 A and 62 B (insertion portions) of pin terminals 61 A and 61 B are inserted into second recesses 44 A and 44 B of damper 40, respectively. It is. In the present embodiment, the first recess 43 and the

second recesses

44A and 44B communicate with each other. The

tips

62A and 62B of the

pin terminals

61A and 61B are pressed against the inner peripheral walls of the

second recesses

44A and 44B by the action of the elastic force (restoring force) of the internal wiring member 50. The

tips

62A and 62B of the

pin terminals

second recesses

44A and 44B. The

pin terminals

61A and 61B of the external wiring member 60 are self-supporting and positioned and held. In this state, solders 65A and 65B (FIGS. 2 to 4) are provided at portions where the

pin terminals

61A and 61B and the other end 52 of the internal wiring member 50 face each other. Next, a damping material 70 is provided in the case 10. As described above, the ultrasonic sensor 100 shown in FIGS. 1 to 4 is obtained.

When the soldering operation is performed, the other end 52 of the internal wiring member 50 and the

pin terminals

61A and 61B are positioned and held. For this reason, the soldering operation can be realized easily and with high certainty. Therefore, according to the configuration of the ultrasonic sensor 100 of the present embodiment, it is possible to effectively suppress the occurrence of poor bonding between the internal wiring member 50 and the external wiring member 60.

The guide portions 46 and 47 (see FIG. 7) provided on the damper 40 can also effectively act on the positioning of the internal wiring member 50 in the Y-axis direction. Since the

guide portions

46 and 47 are not essential components, they are provided as necessary. As a manufacturing method of the ultrasonic sensor 100, the

pin terminals

61A and 61B may be set in the

second recesses

44A and 44B first, and then the other end 52 of the internal wiring member 50 may be set in the first recess 43. These set operations may be performed simultaneously.

In the above configuration, the

tips

62A and 62B of the

pin terminals

61A and 61B of the external wiring member 60 have a function as an insertion portion to be inserted into the

second recesses

44A and 44B. The insertion part may be formed in the holding part 65 as a part of the holding part 65. In this case, the

pin terminals

61A and 61B are positioned in a state where the insertion portion of the holding portion 65 is inserted and locked into the second recess. Even with this configuration, the same operations and effects as described above can be obtained.

The internal wiring member and the external wiring member may be wired using a jig. In this case, the internal wiring member and the external wiring member are connected using solder on the jig. Thereafter, the external wiring member is removed from the jig, and the external wiring member is disposed at a predetermined position in the case. When removing the external wiring member from the jig, it is necessary to consider that the connection portion between the internal wiring member and the external wiring member does not come off. However, in the present invention, since a jig is not used at the time of solder connection, it is not necessary to consider a connection failure that is a concern when the external wiring member is removed from the jig. When the jig is not used as in this embodiment, the length of the internal wiring member is set so that the internal wiring member reaches the position of the jig or the internal wiring member reaches the exact position of the jig. Since it is not necessary to manage and adjust the thickness, the overall length of the internal wiring member can be shortened from this viewpoint, and the manufacturing cost can be reduced.

[First Modification]
FIG. 15 is a perspective view showing a damper 40A according to a first modification of the embodiment. The damper 40A further includes a pair of

protrusions

48A and 48B. The protruding portion 48A is provided by partially projecting the end surface 45S from the end surface 45S of the bulging portion 45A toward the side where the first recess 43 is located. The protruding portion 48B is provided by projecting the end surface 45S partially from the end surface 45S of the bulging portion 45B toward the side where the first recess 43 is located. The protrusions 48 A and 48 B cover the first recess 43 from the opening side of the case 10. That is, the extending

portions

52A and 52B are disposed between the protruding

portions

48A and 48B and the first recess 43, respectively. The other end 52 of the internal wiring member 50 disposed in the first recess 43 can be more reliably positioned in the Z-axis direction during the soldering operation. It is possible to further suppress the other end 52 of the internal wiring member 50 of the ultrasonic sensor 100 from coming off from the first recess 43 in the Z-axis direction by the presence of the

protrusions

48A and 48B. The

guide portions

46 and 47 and the protruding

portions

48A and 48B correspond to the “lead-out portion” of the present invention.

As in the ultrasonic sensor 100A shown in FIG. 16, the

pin terminals

61A and 61B may be arranged inside the pair of projecting

portions

48A and 48B. In this case, the pair of

protrusions

48A and 48B can also act on the positioning of the external wiring member 60 (

pin terminals

61A and 61B) in the Y-axis direction.

[Second Modification]
FIG. 17 is a cross-sectional view showing an ultrasonic sensor 100B according to a second modification of the embodiment. The ultrasonic sensor 100 B further includes an adhesive 49 that adheres the internal wiring member 50 to the end surface 45 S of the damper 40. As the adhesive 49, a silicone-based adhesive, an instantaneous adhesive, or the like can be used. Since it forms in this way, it can suppress more that the connection of the internal wiring member 50 of the ultrasonic sensor 100 and the external wiring member 60 is disconnected before providing the damping material 70. Note that the adhesive 49 may bond not only the internal wiring member 50 and the end face 45S of the damper 40 but also the external wiring member 60 and the end face 45S of the damper 40.

[Third Modification]
FIG. 18 is a cross-sectional view showing an ultrasonic sensor 100C in a third modification of the embodiment. The ultrasonic sensor 100C further includes a fixing member 90. The fixing member 90 has a substantially C-shape, and two end portions are attached in contact with the end surface 45S of the damper 40. The fixing member 90 is provided so as to press the pin terminals 61 A and 61 B of the external wiring member 60 against the other end 52 of the internal wiring member 50. Since it forms in this way, it can suppress more that the connection of the internal wiring member 50 of the ultrasonic sensor 100 and the external wiring member 60 is disconnected before providing the damping material 70.

[Fourth Modification]
FIG. 19 is a plan view showing a damper 40D according to a fourth modification of the embodiment. As shown in FIG. 19, the two second recesses 44 A and 44 B are formed so as not to communicate with the first recess 43. In this case, the first recess 43, the second recess 44A, and the second recess 44B each form an independent recess (hole). The

pin terminals

61A and 61B and the other end 52 of the internal wiring member 50 are secured to each other by solder. Also with this configuration, the same operations and effects as in the above embodiment can be obtained.

[Fifth Modification]
FIG. 20 is a plan view showing a damper 40E according to a fifth modification of the embodiment. As shown in FIG. 20, one second recess 44 K is provided on the main surface 42 of the damper 40. When viewed in plan from the normal direction to the bottom surface of the case 10, the reference position PC is formed in a portion of the second recess 44 K that is positioned farthest from the first recess 43. In FIG. 20, a configuration in which the second recess 44 K does not communicate with the first recess 43 is illustrated, but the second recess 44 K may communicate with the first recess 43. The

pin terminals

[Sixth Modification]
FIG. 21 is a plan view showing a damper 40F according to a sixth modification of the embodiment. In the above-described ultrasonic sensor, the damper includes the

guide portions

46 and 47 and the protruding

portions

48A and 48B, but is not limited thereto. As shown in FIG. 21, the damper 40F has

protrusions

48A and 48B, and does not have

guide portions

46 and 47. In this case, the

protrusions

48A and 48B correspond to the “lead-out part” of the present invention. Also with this configuration, the same operations and effects as in the above embodiment can be obtained.

[Other variations]
In the above-described ultrasonic sensor, the piezoelectric element 20 is made of a lead zirconate titanate ceramic, but is not limited thereto. For example, the piezoelectric element 20 may be made of a non-lead piezoelectric ceramic material such as potassium sodium niobate and alkali niobate ceramics. In the above-described ultrasonic sensor, the external wiring member 60 has the

pin terminals

61A and 61B, but is not limited thereto. For example, the

pin terminals

61A and 61B may be lead wires.

As mentioned above, although embodiment and each modification based on this invention were described, embodiment and each modification disclosed this time are illustrations in all points, and are not restrictive. The technical scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

The ultrasonic sensor according to the present invention can be used, for example, in a car back sonar, a car corner sonar, and a parking spot sensor for detecting the presence of a space between an obstacle such as a side wall and a car in parallel parking. it can.

10 case, 11 lower end, 12 upper end, 13 inner bottom surface, 14 pedestal, 20 piezoelectric element, 21 first drive electrode, 22 second drive electrode, 23 gap, 30 reinforcing material, 40, 40A, 40D, 40E damper, 41 convex portion, 42 main surface, 43 first concave portion, 43A, 43B side wall portion, 43C inner wall portion, 43D bottom surface portion, 44A, 44B, 44K second concave portion, 45A, 45B bulging portion, 45C columnar portion, 45S end surface, 46, 47 guide part, 48A, 48B protruding part, 49 adhesive, 50 internal wiring member, 51 one end, 52 other end, 52A, 52B extension part, 53 halfway part, 57 first wiring, 58 second wiring , 60 External wiring member, 61A, 61B pin terminal, 62A, 62B tip (insertion part), 65 holding part, 65A, 65B Solder, 70 damping material, 90 fixing member, 100, 100A, 100B, 100C ultrasonic sensor, AR30, AR40, AR50, AR62A, AR62B, DR1 arrows, PA, PB, PC reference position.

Claims

A bottomed cylindrical case,
A piezoelectric element provided on the inner bottom surface of the case;
A damper disposed in the case and having a main surface opposite to the side facing the piezoelectric element, the main surface having a first recess and a second recess;
An internal wiring member having one end connected to the piezoelectric element, drawn from the side where the piezoelectric element is located toward the first recess, and the other end disposed in the first recess;
An external wiring member that has an insertion portion, the insertion portion is disposed in the second recess, and is drawn out of the case through the opening of the case,
The internal wiring member and the external wiring member are electrically connected to each other by inserting the other end of the internal wiring member into the first recess and inserting the insertion portion of the external wiring member into the second recess. Connected to
The first recess has an inner wall portion facing from the side where the second recess is located with respect to the other end of the internal wiring member disposed in the first recess.
Ultrasonic sensor.
When the first concave portion and the second concave portion are viewed in a plan view from the normal direction with respect to the bottom surface of the case, a portion of the second concave portion that is located farthest when viewed from the first concave portion is set as a reference position. The inner wall portion is formed so as to be positioned between the reference position and the internal wiring member.
The ultrasonic sensor according to claim 1.
The damper further includes a lead-out portion provided so as to lead the internal wiring member along an arbitrary path.
The ultrasonic sensor according to claim 1 or 2.
The lead-out portion includes a guide portion provided to be recessed toward the inside of the damper,
The internal wiring member has a portion disposed in the guide portion.
The ultrasonic sensor according to claim 3.
The lead-out portion includes a bulging portion provided so as to bulge from the main surface toward a side where the opening of the case is located, and a side where the first concave portion is located from the bulging portion. And a pair of protrusions provided so as to protrude toward the
The external wiring member has a portion disposed between the pair of protrusions.
The ultrasonic sensor according to claim 3 or 4.
The internal wiring member has an extending portion that is disposed on the first concave portion side when viewed from the protruding portion.
The ultrasonic sensor according to claim 5.
Two of the second recesses are provided on the main surface,
The external wiring member has the two insertion portions respectively disposed in the two second recesses,
The two second recesses are formed to communicate with the first recess.
The ultrasonic sensor according to claim 1.
A portion of the external wiring member that is electrically connected to the internal wiring member and a portion of the internal wiring member that is electrically connected to the external wiring member are normal to the bottom surface of the case. The ultrasonic sensor according to claim 1, which extends in the same direction along the direction.
An adhesive that adheres the internal wiring member to the damper;
The ultrasonic sensor according to claim 1.
A fixing member attached in contact with the damper;
The fixing member presses the external wiring member against the internal wiring member.
The ultrasonic sensor according to claim 1.
A bottomed cylindrical case,
A piezoelectric element provided on the inner bottom surface of the case;
A damper disposed in the case and having a main surface opposite to the side facing the piezoelectric element, the main surface having a first recess and a second recess;
An internal wiring member having one end connected to the piezoelectric element, drawn from the side where the piezoelectric element is located toward the first recess, and the other end disposed in the first recess;
An external wiring member that has an insertion portion, the insertion portion is disposed in the second recess, and is drawn out of the case through the opening of the case,
The said 1st recessed part has an inner wall part which opposes from the side in which the said 2nd recessed part is located with respect to the said other end of the said internal wiring member arrange | positioned in the said 1st recessed part. A method of manufacturing an ultrasonic sensor according to claim 1,
The manufacturing method is
Holding the internal wiring member in the first recess by inserting the other end of the internal wiring member into the first recess;
Holding the external wiring member in the second recess by inserting the insertion portion of the external wiring member into the second recess; and
Electrically connecting the internal wiring member and the external wiring member to each other,
Manufacturing method of ultrasonic sensor.