Object detection device

Abstract

To provide an object detection device capable of suppressing an unnecessary vibration in a wall part being an attachment object such as a bumper, without requiring shape processing with respect to the wall part.SOLUTION: A vibration control member 16 is adhered to one surface 94a of a wall part 94, is formed to enclose a vibrator 14 on the one surface 94a, and is constituted by a predetermined vibration control material. The vibration control member 16 includes a first short constitution part 166 and a second short constitution part 168. The first and second short constitution parts 166, 168 are the parts where a predetermined material length Ld1 is partially shortened in the vibration control member 16 on a vertical cross section passing a center of the vibrator 14 and parallel to a first direction D1. The predetermined material length Ld1 is the length Ld1 to be occupied in the first direction D1 by each predetermined material part 164 which is the part constituted by the predetermined vibration control material in the vibration control member 16.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to an object detection device attached to a wall portion.

Background Art

[0002] As this type of object detection device, for example, an obstacle detection device described in Patent Document 1 has been conventionally known. The obstacle detection device described in this Patent Document 1 is one in which an ultrasonic sensor including an ultrasonic vibrator is attached to the inner surface of a bumper. This obstacle detection device includes a protrusion structure composed of a plurality of protrusions protruding from the inner surface of the bumper as a part of the bumper.

[0003] The plurality of protrusions are arranged around the ultrasonic vibrator. Then, the plurality of protrusions are vibrated together with the vibration of the ultrasonic vibrator, whereby unnecessary vibration in the bumper is reduced.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In order to provide the obstacle detection device of Patent Document 1, since a plurality of protrusions need to be formed as a part of the shape of the bumper, it is necessary to perform processing for forming the plurality of protrusions on the bumper itself. However, since the material and shape of the bumper are different for each product, when performing processing for forming a plurality of protrusions on the bumper itself, for example, a design of the protrusions is required for each product. As a result of the inventors' detailed examination, the above has been found.

[0006] In view of the above, the present invention aims to provide an object detection device that can suppress unwanted vibrations of a wall, such as a bumper, without requiring any shaping of the wall to which it is attached. [Means for solving the problem]

[0007] To achieve the above objective, the object detection device described in claim 1 is: An object detection device (10) is attached to a wall portion (94) having thickness in one direction (D1), A vibrator (14) is connected to one side (94a) of the wall portion so as to transmit vibrations to that side, It comprises a vibration damping section (16) attached to one side of the wall, formed on that one side to surround the vibrator, and made of a predetermined material, The oscillator has a conversion function that converts one of the vibrations generated in the oscillator and the electrical signal into the other. The vibration damping section has short components (166, 168, 178), The short-shaped component is configured such that, in a longitudinal cross-section passing through the center of the vibrator and parallel to the aforementioned one direction, the length (Ld1) occupied by the predetermined material portion (164) in that one direction is partially shortened within the vibration damping section. The specified material portion is the part of the vibration damping section that is made of the specified material mentioned above.

[0008] In this way, the bending stiffness of the wall to which the vibration damping element is attached will vary as it moves away from the vibrator along one side of the wall. For example, areas of the wall to which the vibration damping element is attached will alternate with areas of lower bending stiffness as it moves away from the vibrator along one side of the wall. The higher the bending stiffness, the less the wall to which the vibration damping element is attached will vibrate. In other words, areas of the wall that are less prone to vibration and areas that are more prone to vibration will alternate as they move away from the vibrator along one side of the wall.

[0009] Therefore, vibrations of the wall transmitted from the inner side to the outer side of the damping section surrounding the transducer, and vibrations of the wall transmitted from the outer side to the inner side of the damping section, are both easily attenuated. In other words, vibrations of the wall transmitted in this manner can be reduced. As a result, it is possible to suppress vibrations in the peripheral parts of the wall located around the opposing part that faces the transducer (i.e., unwanted vibrations of the wall).

[0010] Furthermore, since the vibration damping section is attached to one side of the wall, there is no need to modify the shape of the wall to which it is attached.

[0011] In addition, in some cases, each element in the application documents may be denoted by a reference numeral in parentheses. In this case, the reference numeral merely indicates one example of the correspondence between the element and the specific configuration described in the embodiments described later. Therefore, the present invention is not limited in any way by the notation of reference numerals. [Brief explanation of the drawing]

[0012] [Figure 1] This is a perspective view showing the exterior of a vehicle equipped with an ultrasonic sensor in the first embodiment. [Figure 2] This is a functional block diagram showing the schematic configuration of an object detection system using an ultrasonic sensor in the first embodiment. [Figure 3] This is a longitudinal cross-sectional view schematically showing the general configuration of the ultrasonic sensor in the first embodiment. [Figure 4] This is a view from the arrow pointing in direction IV in Figure 3. [Figure 5] Figure 3 is a schematic cross-sectional view showing the VV cross-section, and it shows the vibration damping member included in the ultrasonic sensor as a standalone component. [Figure 6] Figure 3 is a cross-sectional view that schematically represents the ultrasonic waves emitted from the ultrasonic sensor of the first embodiment into the external space. [Figure 7] Figure 3 is a cross-sectional view that schematically represents the ultrasonic waves emitted into the external space from an ultrasonic sensor of a comparative example compared to the first embodiment. [Figure 8] In the second embodiment, it is a longitudinal sectional view schematically showing the schematic configuration of the ultrasonic sensor, and is a figure corresponding to FIG. 3. [Figure 9] It is a view in the IX direction in FIG. 8, and is a figure showing the fixing member included in the ultrasonic sensor alone. [Figure 10] In the ultrasonic sensor of the second embodiment, it is a figure schematically showing the vibration waveform of the vibration passing through the first and second partial spaces of the vibration damping member between the wall portion and the fixing base portion. [Figure 11] In the third embodiment, it is a longitudinal sectional view schematically showing the schematic configuration of the ultrasonic sensor, and is a figure corresponding to FIG. 3. [Figure 12] In the fourth embodiment, it is a longitudinal sectional view schematically showing the schematic configuration of the ultrasonic sensor, and is a figure corresponding to FIG. 3. [Figure 13] In the fifth embodiment, it is a longitudinal sectional view schematically showing the schematic configuration of the ultrasonic sensor, and is a figure corresponding to FIG. 3. [Figure 14] In the sixth embodiment, it is a longitudinal sectional view schematically showing the schematic configuration of the ultrasonic sensor, and is a figure corresponding to FIG. 3. [Figure 15] In the seventh embodiment, it is a longitudinal sectional view schematically showing the schematic configuration of the ultrasonic sensor, and is a figure corresponding to FIG. 3. [Figure 16] In the eighth embodiment, it is a longitudinal sectional view schematically showing the schematic configuration of the ultrasonic sensor, and is a figure corresponding to FIG. 3. [Figure 17] In the ninth embodiment, it is a longitudinal sectional view schematically showing the schematic configuration of the ultrasonic sensor, and is a figure corresponding to FIG. 3. [Figure 18] In the tenth embodiment, it is a longitudinal sectional view schematically showing the schematic configuration of the ultrasonic sensor, and is a figure corresponding to FIG. 3. [Figure 19] In the eleventh embodiment, it is a longitudinal sectional view schematically showing the schematic configuration of the ultrasonic sensor, and is a figure corresponding to FIG. 3. [Figure 20]In the 12th embodiment, this is a schematic cross-sectional view showing a single vibration damping member in a cross-section corresponding to the VV cross-section in Figure 3, and corresponds to Figure 5. [Figure 21] In the 13th embodiment, this is a schematic cross-sectional view showing a single vibration damping member in a cross-section corresponding to the XXI-XXI cross-section in Figure 15, and is the same figure as Figure 5. [Figure 22] In the 14th embodiment, this is a schematic cross-sectional view showing a single vibration damping member in a cross-section corresponding to the VV cross-section in Figure 3, and corresponds to Figure 5. [Figure 23] In the 15th embodiment, this is a schematic cross-sectional view showing a single vibration damping member in a cross-section corresponding to the XXI-XXI section of Figure 15, and is the same figure as Figure 5. [Figure 24] In the 16th embodiment, this is a schematic cross-sectional view showing a single vibration damping member in a cross-section corresponding to the VV cross-section in Figure 3, and corresponds to Figure 5. [Modes for carrying out the invention]

[0013] The embodiments will be described below with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other are denoted by the same reference numerals in the drawings.

[0014] (First Embodiment) As shown in Figures 1 and 2, the ultrasonic sensor 10 of this embodiment is mounted on, for example, a vehicle 90, which is a moving object. The ultrasonic sensor 10 is configured to generate and output a detection signal corresponding to the presence of an object B (e.g., an obstacle) in the external space SG surrounding the vehicle 90 when mounted on the vehicle 90. In other words, the ultrasonic sensor 10 has a configuration as an on-board clearance sonar that is mounted on a vehicle 90. This ultrasonic sensor 10 corresponds to the object detection device of this disclosure.

[0015] The vehicle 90 is typically a so-called four-wheeled automobile and has a box-shaped body 91. The body 91 includes body panels 92 and bumpers 93, which are plate-shaped body parts that constitute the outer body. The bumpers 93 are provided at the front and rear ends of the body 91, respectively. In this embodiment, the ultrasonic sensor 10 is configured to be attached to the bumper 93. The state in which the ultrasonic sensor 10 is mounted on the vehicle 90 by being attached to the bumper 93 will be referred to as the "mounted state" below.

[0016] Specifically, multiple (for example, four) ultrasonic sensors 10 are mounted on the front bumper, i.e., the front bumper 93 of the vehicle body 91. Each of the multiple ultrasonic sensors 10 mounted on the front bumper is positioned at least differently in the vehicle width direction. Similarly, multiple (for example, four) ultrasonic sensors 10 are also mounted on the rear bumper, i.e., the rear bumper 93 of the vehicle body 91.

[0017] As can be seen from the fact that the ultrasonic sensor 10 is shown as a hidden dashed line in Figure 1, the ultrasonic sensor 10 is mounted on the inside of the bumper 93 and is not visible from the outside of the bumper 93.

[0018] As shown in Figure 2, the ultrasonic sensor 10 constitutes part of the object detection system 70 that detects object B. In addition to the multiple ultrasonic sensors 10, the object detection system 70 includes a transmitting unit 701, a receiving unit 702, a signal generating unit 703, a signal processing unit 704, an object detection unit 705, and a control unit 706.

[0019] The transmitting unit 701 is electrically connected to the ultrasonic sensor 10 so as to input a drive signal to the ultrasonic sensor 10. Specifically, the transmitting unit 701 has a digital-to-analog conversion circuit and the like. That is, the transmitting unit 701 is configured to perform digital-to-analog conversion and other processing on the transmission signal output from the signal generation unit 703, and to apply the AC voltage generated as a drive signal to the transducer 14 of the ultrasonic sensor 10.

[0020] The receiving unit 702 is configured to perform signal processing such as amplification and analog / digital conversion on the received signal generated by the transducer 14 in response to the ultrasonic reception result from the ultrasonic sensor 10, and output it to the signal processing unit 704. Specifically, the receiving unit 702 has an amplification circuit, an analog / digital conversion circuit, etc. The transmitting unit 701 and the receiving unit 702 may be provided corresponding to each of the multiple ultrasonic sensors 10.

[0021] The signal generation unit 703 is configured to generate a transmission signal for outputting a transmission wave (in other words, a probe wave) of a predetermined frequency from the ultrasonic sensor 10 and input it to the transmission unit 701. Specifically, the signal generation unit 703 is configured to change the frequency of the drive signal based on an electrical signal indicating a transmission instruction output from the control unit 706.

[0022] The signal processing unit 704 is configured to perform various signal processing, such as filtering, on the received signal output from the receiving unit 702. The signal processing unit 704 is also configured to output the processed signal, which is the result of the various signal processing, to the object detection unit 705.

[0023] The object detection unit 705 measures the shape of object B (see Figure 1) based on the reception result of the received wave, which includes the reflected wave generated when the probe wave is reflected by object B present around the vehicle 90. The object detection unit 705 then outputs the detection result, which indicates the shape of object B and other characteristics obtained based on the reception result of the reflected wave, to the control unit 706.

[0024] For example, the signal generation unit 703, the signal processing unit 704, and the object detection unit 705 each include a DSP that operates according to a predetermined program. DSP stands for Digital Signal Processor. Furthermore, the signal generation unit 703, the signal processing unit 704, and the object detection unit 705 may be provided in common for multiple ultrasonic sensors 10.

[0025] The control unit 706 has the configuration of an in-vehicle microcomputer, which includes a CPU, RAM, ROM, non-volatile rewritable memory, etc. (not shown). In other words, the control unit 706 reads and executes a computer program stored in the ROM or non-volatile rewritable memory, which are non-transitional physical recording media. When this computer program is executed, a method corresponding to the computer program is performed.

[0026] For example, the control unit 706 controls various operations of the object detection system 70, including the transmission and reception operations of each of the multiple ultrasonic sensors 10, by reading and executing a predetermined control program. The control unit 706 also outputs the detection results obtained from the object detection unit 705 to an external device. The control unit 706 is provided in common for all of the multiple ultrasonic sensors 10.

[0027] The ultrasonic sensor 10 shown in Figures 3 and 4 is configured to transmit and receive ultrasonic waves. Figures 3 and 4 show one of several ultrasonic sensors 10 attached to the bumper 93 in its mounted state.

[0028] The ultrasonic sensor 10 is attached to a wall portion 94, which is a part of the bumper 93. For example, when the ultrasonic sensor 10 transmits a transmission wave, which is an ultrasonic wave, it transmits the wave by ultrasonically vibrating the wall portion 94 in a predetermined first direction D1 in response to a drive signal. The ultrasonic sensor 10 is also configured to receive a received wave from the external space SG, which includes a reflected wave generated when the transmitted wave is reflected by an object B (see Figure 2) present around the vehicle 90 (see Figure 1), and to generate and output a received signal according to the reception result of the received wave.

[0029] Note that the first direction D1 corresponds to one direction in this disclosure. In this embodiment, any one direction perpendicular to the first direction D1 is defined as the second direction D2, and the direction perpendicular to both the first direction D1 and the second direction D2 is defined as the third direction D3. Figure 3 shows a longitudinal cross-section of the transducer 14 of the ultrasonic sensor 10 that passes through the center and is parallel to the first direction D1, specifically the III-III cross-section in Figure 4.

[0030] As shown in Figures 3 and 4, the wall portion 94 to which the ultrasonic sensor 10 is attached is formed in a flat plate shape with thickness in the first direction D1. That is, the wall portion 94 is formed to extend in the second direction D2 and the third direction D3.

[0031] Furthermore, the wall portion 94 has one surface 94a formed on one side in the first direction D1, and another surface 94b formed on the other side opposite to the first direction D1. Since the wall portion 94 is a part of the bumper 93, the other surface 94b of the wall portion 94 constitutes a part of the surface (in other words, the design surface) of the bumper 93, and if the bumper 93 in Figure 3 is a front bumper, it will be the surface facing the front of the vehicle. Therefore, one surface 94a of the wall portion 94 becomes the inner surface of the bumper 93 that is not visible from the exterior of the vehicle 90. The bumper 93 is made of a resin such as polypropylene.

[0032] The ultrasonic sensor 10 comprises a transducer 14, a vibration damping member 16, and an intervening adhesive layer 22. The ultrasonic sensor 10 is attached to one side 94a of the wall portion 94. That is, one side 94a of the wall portion 94 is the mounting surface to which the ultrasonic sensor 10 is attached. Therefore, all components of the ultrasonic sensor 10, such as the transducer 14, the vibration damping member 16, and the intervening adhesive layer 22, are arranged on one side of the wall portion 94 in the first direction D1.

[0033] The vibrator 14 is connected to one surface 94a of the wall portion 94. Specifically, the vibrator 14 is adhesively fixed to one surface 94a of the wall portion 94 via an intervening adhesive layer 22. This adhesive fixing allows vibrations to be transmitted between the vibrator 14 and the wall portion 94.

[0034] When the ultrasonic sensor 10 transmits a wave, the transducer 14 applies ultrasonic vibration to one side 94a of the wall 94. Conversely, when the wall 94 receives a reflected wave from the external space SG, the vibration of the wall 94 caused by the reflected wave is transmitted from the wall 94 to the transducer 14.

[0035] Specifically, as shown in Figures 3 and 4, the transducer 14 is configured to include a drive element, which acts as an electromechanical energy conversion element that performs the function of converting ultrasonic vibrations in a first direction D1 and electrical signals from one to the other. For example, the drive element is composed of multiple stacked piezoelectric elements (in other words, piezo elements).

[0036] With this configuration, the transducer 14 generates ultrasonic vibrations that expand and contract in the first direction D1 when it receives an electrical signal as a drive signal from the transmitter 701 (see Figure 2). In addition, the transducer 14 generates an electrical signal as a received signal corresponding to the ultrasonic vibrations in the first direction D1, and outputs this electrical signal to the receiver 702 (see Figure 2).

[0037] In other words, the transducer 14 of this embodiment has both a transmitting function that converts an electrical signal into ultrasonic vibrations and emits those ultrasonic vibrations, and a receiving function that converts the ultrasonic vibrations received by the transducer 14 into an electrical signal and outputs that electrical signal. In short, the transducer 14 has a conversion function that converts one of the electrical signal and the ultrasonic vibrations generated in the transducer 14 into the other.

[0038] Furthermore, the vibrator 14 has one end face 141 formed on one side in the first direction D1 and another end face 142 formed on the other side in the first direction D1. The other end face 142 of the vibrator 14 faces one side 94a of the wall portion 94 and is bonded to the one side 94a of the wall portion 94 via the intervening adhesive layer 22.

[0039] The vibration damping member 16 is a vibration damping component that suppresses unwanted vibrations generated in the wall portion 94. This vibration damping member 16 is formed in an annular shape on one surface 94a of the wall portion 94 so as to surround the vibrator 14 around its entire circumference. Therefore, a housing space 16a is formed inside the vibration damping member 16, which is formed as a through hole that penetrates the vibration damping member 16 in a first direction D1 and accommodates the vibrator 14.

[0040] In detail, the vibration damping member 16 is formed in an annular shape with a vibration damping axis CL, which is the axis extending in the first direction D1, and is positioned so that the vibration damping axis CL passes through the center of the vibrator 14. Therefore, the first direction D1 corresponds to the axial direction of the vibration damping axis CL, and the second direction D2 and the third direction D3 each correspond to one of the radial directions Dr of the vibration damping axis CL (i.e., the radial direction Dr of the vibration damping section).

[0041] The vibration damping member 16 has one end face 161 formed on one side in the first direction D1 and another end face 162 formed on the other side in the first direction D1. This other end face 162 of the vibration damping member 16 is an adhesive surface that is attached to one side 94a of the wall portion 94. Specifically, the other end face 162 of the vibration damping member 16 faces one side 94a of the wall portion 94 and is bonded to one side 94a of the wall portion 94 via the intervening adhesive layer 22. In short, the vibration damping member 16 is attached to one side 94a of the wall portion 94 by the intervening adhesive layer 22, and is thereby bonded and fixed to that side 94a.

[0042] Furthermore, the vibration damping member 16 is composed of a predetermined vibration damping material. Various resin materials can be used as this predetermined vibration damping material, and in this embodiment, PBT is used as the predetermined vibration damping material. PBT stands for polybutylene terephthalate. The predetermined vibration damping material corresponds to the predetermined material in this disclosure.

[0043] Furthermore, as shown in Figures 3 and 5, the vibration damping member 16 has a first partial space 16b and a second partial space 16c formed in a groove shape that is cut in from the other side in the first direction D1. These first partial space 16b and second partial space 16c are spaces partially formed in the vibration damping member 16. For example, in this embodiment, the spatial length Lsp of the first partial space 16b in the first direction D1 (in other words, the groove depth of the first partial space 16b) is the same as that of the second partial space 16c.

[0044] The first subspace 16b and the second subspace 16c are annular grooves that extend in a ring shape to surround the oscillator 14 when viewed along the first direction D1. For example, the first subspace 16b and the second subspace 16c are filled with air. Note that the oscillator 14 is not shown in Figure 5.

[0045] Here, the vibration damping member 16 is provided with first and second partial spaces 16b and 16c. However, in order to increase the adhesive strength between the wall portion 94 and the vibration damping member 16, it is preferable that the area of ​​the other end surface 162 of the vibration damping member 16 that is adhered to one surface 94a of the wall portion 94 be larger. In this embodiment, the first and second partial spaces 16b and 16c are provided so that sufficient adhesive strength is obtained between the wall portion 94 and the vibration damping member 16. Furthermore, for example, the total area of ​​the first and second partial spaces 16b and 16c as seen from the other side of the first direction D1 is equal to or greater than the area of ​​the other end surface 162 excluding the first and second partial spaces 16b and 16c.

[0046] Specifically, the first partial space 16b and the second partial space 16c form an annular shape with respect to the vibration damping axis CL, and are formed as spaces that extend in the first direction D1 while maintaining this annular shape with respect to the vibration damping axis CL. The first partial space 16b is positioned on the inner circumference side (in other words, the side of the vibrator 14) relative to the second partial space 16c. The inner circumference side of the vibration damping member 16, the inner circumference side of the first partial space 16b, and the inner circumference side of the second partial space 16c are all, in other words, on the inside in the radial direction Dr of the vibration damping.

[0047] As the first and second partial spaces 16b and 16c are formed in this manner, in the longitudinal section of Figure 3, the length Ld1 (i.e., the predetermined material length Ld1) occupied by the predetermined material portion 164 of the vibration damping member 16 in the first direction D1 differs depending on the part of the vibration damping member 16. The predetermined material portion 164 is the part of the vibration damping member 16 that is made of the predetermined vibration damping material.

[0048] In other words, the vibration damping member 16 has a first short component 166 and a second short component 168, which are configured as parts in the longitudinal section of Figure 3 where the predetermined material length Ld1 is partially shortened within the vibration damping member 16. The vibration damping member 16 also has first, second, and third long component 165, 167, and 169, which have a longer predetermined material length Ld1 than the first and second short component 166 and 168.

[0049] Each of these components 165 to 169 is arranged in a ring shape with respect to the vibration damping axis CL. In other words, each of these components 165 to 169 is arranged to surround the vibrator 14 when viewed in the direction along the first direction D1.

[0050] Furthermore, these components 165 to 169 are stacked in the order of the first elongated component 165, the first short component 166, the second elongated component 167, the second short component 168, and the third elongated component 169, starting from the inner circumference side of the vibration damping member 16. In addition, these components 165 to 169 are integrally constructed.

[0051] In this embodiment, the portion of the predetermined material portion 164 of the vibration damping member 16 that belongs to the first elongated component 165 may be referred to as the predetermined material portion 164a of the first elongated component 165. Also, the portion of the predetermined material portion 164 that belongs to the second elongated component 167 may be referred to as the predetermined material portion 164c of the second elongated component 167. Also, the portion of the predetermined material portion 164 that belongs to the third elongated component 169 may be referred to as the predetermined material portion 164e of the third elongated component 169. Also, the portion of the predetermined material portion 164 that belongs to the first short component 166 may be referred to as the predetermined material portion 164b of the first short component 166. Also, the portion of the predetermined material portion 164 that belongs to the second short component 168 may be referred to as the predetermined material portion 164d of the second short component 168.

[0052] Furthermore, the first partial space 16b of the vibration damping member 16 is arranged in series with respect to the predetermined material portion 164b of the first short-shaped component 166 on the other side in the first direction D1, and the predetermined material portion 164b of the first short-shaped component 166 forms the bottom of the first partial space 16b. Therefore, the first partial space 16b is formed as a part of the first short-shaped component 166.

[0053] Furthermore, the predetermined material portion 164a of the first elongated component 165 faces the first partial space 16b from the inner circumference side of the vibration damping member 16, and the predetermined material portion 164c of the second elongated component 167 faces the first partial space 16b from the outer circumference side of the vibration damping member 16. That is, the first partial space 16b is formed between two predetermined material portions 164a and 164c that are spaced apart in the vibration damping radial direction Dr perpendicular to the first direction D1 in the longitudinal cross-section of Figure 3.

[0054] Similarly, the second partial space 16c of the vibration damping member 16 is arranged in series with respect to the predetermined material portion 164d of the second short-shaped component 168 on the other side in the first direction D1, and the predetermined material portion 164d of the second short-shaped component 168 forms the bottom of the second partial space 16c. Therefore, the second partial space 16c is formed as a part of the second short-shaped component 168.

[0055] Furthermore, the predetermined material portion 164c of the second elongated component 167 faces the second partial space 16c from the inner circumference side of the vibration damping member 16, and the predetermined material portion 164e of the third elongated component 169 faces the second partial space 16c from the outer circumference side of the vibration damping member 16. That is, the second partial space 16c is formed between two predetermined material portions 164c and 164e that are spaced apart in the radial direction Dr of the vibration damping portion in the longitudinal cross-section of Figure 3.

[0056] The intervening adhesive layer 22 is an adhesive layer interposed between the vibrator 14 and the vibration damping member 16 and the wall portion 94. Specifically, the intervening adhesive layer 22 is positioned between the other end face 142 of the vibrator 14 and one side 94a of the wall portion 94, thereby bonding and fixing the vibrator 14 and the wall portion 94. At the same time, the intervening adhesive layer 22 is also positioned between the other end face 162 of the vibration damping member 16 and one side 94a of the wall portion 94, thereby bonding and fixing the vibration damping member 16 and the wall portion 94.

[0057] For example, the intervening adhesive layer 22 may be composed of adhesive tape, or it may be an adhesive that is applied to one surface 94a of the wall portion 94 and hardens to provide adhesion.

[0058] Various synthetic resin materials, such as epoxy resins, can be used as the constituent material for the intervening adhesive layer 22. The thickness of this intervening adhesive layer 22 is formed to be sufficiently small compared to the wavelength of the transmitted and received waves (for example, a thickness of 100 μm or less, or less than one-eighth of the wavelength). Furthermore, the intervening adhesive layer 22 is configured such that its acoustic impedance is between the acoustic impedance at the other end face 142 of the transducer 14 and the acoustic impedance of the wall portion 94, through the selection of its constituent material and other factors.

[0059] In this embodiment, if there are any adhesive layers other than the intervening adhesive layer 22 that are involved in the transmission of ultrasonic vibrations and whose thickness has not been described, these adhesive layers shall also be assumed to be formed with a thickness that is sufficiently small compared to the wavelength of the transmitted and received waves, similar to the intervening adhesive layer 22.

[0060] As described above, according to this embodiment, as shown in Figures 3 and 5, the vibration damping member 16 is attached to one surface 94a of the wall portion 94, formed to surround the vibrator 14 on that surface 94a, and is made of a predetermined vibration damping material. The vibration damping member 16 has a first short component 166 and a second short component 168. The first and second short components 166 and 168 are configured as parts in the vibration damping member 16 where the predetermined material length Ld1 is partially shortened in the vertical cross-section of Figure 3. The predetermined material length Ld1 is the length Ld1 occupied by the predetermined material portion 164, which is made of the predetermined vibration damping material, in the first direction D1.

[0061] As a result, the bending stiffness of the wall portion 94 to which the vibration damping member 16 is attached varies as it moves away from the vibrator 14 in a direction along one surface 94a of the wall portion 94. For example, areas of the wall portion 94 to which the vibration damping member 16 is attached will alternate with areas of low bending stiffness as it moves away from the vibrator 14 in a direction along one surface 94a of the wall portion 94. The higher the bending stiffness, the less the wall portion 94 to which the vibration damping member 16 is attached will vibrate. In other words, in the wall portion 94, areas that vibrate less and areas that vibrate more will alternate as it moves away from the vibrator 14 in a direction along one surface 94a of the wall portion 94.

[0062] Therefore, vibrations of the wall portion 94 transmitted from the inner circumference to the outer circumference of the vibration damping member 16 surrounding the vibrator 14, and vibrations of the wall portion 94 transmitted from the outer circumference to the inner circumference of the vibration damping member 16, are both easily attenuated. In other words, vibrations of the wall portion 94 transmitted in this manner can be reduced. As a result, as shown in Figure 6, it is possible to suppress vibrations in the peripheral portion of the wall portion 94 located around the opposing portion PA (i.e., the vibrator opposing portion PA) that faces the vibrator 14 (i.e., unwanted vibrations of the wall portion 94). In Figure 6, the area occupied by the vibrator opposing portion PA is shown with a dashed line.

[0063] Furthermore, since unwanted vibrations of the wall portion 94 are suppressed, it is possible to suppress the turbulent propagation of vibrations applied from the vibrator 14 and transmitted from the wall portion 94 to the other side in the first direction D1 in the external space SG.

[0064] For example, as shown in Figure 7, let's consider a comparative example ultrasonic sensor 97 in which the vibration damping member 16 does not have the first and second partial spaces 16b and 16c. This comparative example ultrasonic sensor 97 is the same as the ultrasonic sensor 10 of this embodiment, except that the first and second partial spaces 16b and 16c are not provided.

[0065] In this case, for example, when ultrasonic vibration is applied from the transducer 14 to one surface 94a of the wall portion 94, in the comparative example, compared to this embodiment, the ultrasonic vibration applied from the transducer 14 is more likely to spread from the transducer-facing portion PA of the wall portion 94 to the surrounding area.

[0066] In other words, as shown in Figures 6 and 7, in the comparative example, ultrasonic vibrations are emitted to the external space SG not only from the transducer-facing portion PA of the wall 94 but also from its surrounding portion. In contrast, in this embodiment, it is possible to narrow down the portion of the wall 94 that emits ultrasonic vibrations to the external space SG to the transducer-facing portion PA, compared to the comparative example. The multiple arcs shown in Figures 6 and 7 schematically represent the ultrasonic waves emitted from the wall 94 to the external space SG.

[0067] Furthermore, since the vibration damping member 16 is attached to one side 94a of the wall portion 94, there is no need to modify the shape of the wall portion 94 to which it is attached. For example, the ultrasonic sensor 10 can be easily retrofitted to the bumper 93 which includes the wall portion 94.

[0068] (1) Furthermore, according to this embodiment, as shown in Figures 3 and 5, the first and second short components 166 and 168 are arranged to surround the vibrator 14 when viewed in the direction along the first direction D1. Therefore, the parts of the wall 94 to which the vibration damping member 16 is attached that have high bending rigidity and the parts that have low bending rigidity can be alternately arranged around the vibrator 14 in the radial direction Dr of the vibration damping portion. As a result, vibrations transmitted in the wall 94 that spread from the vibrator-facing portion PA (see Figure 6) to its periphery, and vibrations transmitted from the periphery of the vibrator-facing portion PA toward the vibrator-facing portion PA can be attenuated in stages. In short, vibrations transmitted radially from the vibrator-facing portion PA can be attenuated in the wall 94.

[0069] Furthermore, according to this embodiment, as shown in Figure 3, the distance between the first partial space 16b of the vibration damping member 16 and one surface 94a of the wall portion 94 in the first direction D1 is the same as or approximately the same as the thickness of the intervening adhesive layer 22. That is, the distance between the first partial space 16b of the vibration damping member 16 and one surface 94a of the wall portion 94 in the first direction D1 is small compared to the length that the first partial space 16b occupies in the first direction D1. The same applies to the second partial space 16c.

[0070] Therefore, compared to the case where the distance between the first and second partial spaces 16b and 16c and one surface 94a is larger than in this embodiment, it is possible to increase the difference in rigidity between the part of the wall portion 94 to which the vibration damping member 16 is attached that has high bending rigidity and the part that has low bending rigidity. Accordingly, it is possible to further attenuate vibrations transmitted from the transducer-facing part PA to the surrounding part of the wall portion 94, and vibrations transmitted from the surrounding part to the transducer-facing part PA.

[0071] Furthermore, according to this embodiment, as shown in Figure 3, in the first and second partial spaces 16b and 16c of the vibration damping member 16, the other side in the first direction D1 is open on the vibration damping member 16 alone, but is closed by the intervening adhesive layer 22 and one side 94a of the wall portion 94. As a result, the first and second partial spaces 16b and 16c become sealed spaces. Therefore, it is possible to prevent foreign matter such as mud or water from entering these first and second partial spaces 16b and 16c.

[0072] (Second Embodiment) Next, a second embodiment will be described. In this embodiment, the differences from the first embodiment described above will be mainly explained. Furthermore, parts that are the same as or equivalent to the above embodiment will be omitted or simplified in their description. The same applies to the descriptions of the embodiments described later.

[0073] As shown in Figure 8, in this embodiment, the ultrasonic sensor 10 comprises a transducer 14, a vibration damping member 16, and an intervening adhesive layer 22, similar to the first embodiment. In addition, the ultrasonic sensor 10 is equipped with a fixing member 24 as a fixing part.

[0074] As shown in Figures 8 and 9, the fixing member 24 has a fixing base portion 241 and a fixing projection portion 242. The fixing base portion 241 and the fixing projection portion 242 are integrally constructed. For example, the fixing member 24 is made of a highly rigid resin material such as PBT. The fixing member 24 is positioned on one side of the vibrator 14 in the first direction D1.

[0075] The fixed base portion 241 is disc-shaped and concentric with the vibration damping member 16, and the outer diameter of the fixed base portion 241 is the same as or approximately the same as the outer diameter of the vibration damping member 16. The fixed base portion 241 is positioned on one side in the first direction D1 with respect to both the vibration damping member 16 and the vibrator 14.

[0076] The fixed base portion 241 has one end face 241a formed on one side of the fixed base portion 241 in the first direction D1, and another end face 241b formed on the other side of the fixed base portion 241 in the first direction D1.

[0077] The other end face 241b of the fixed base portion 241 faces one end face 161 of the vibration damping member 16 and is joined to that end face 161 by adhesive or the like. In short, the vibration damping member 16 is connected to the fixed member 24. As a result, the fixed member 24 is fixed to the wall portion 94 around the vibrator 14.

[0078] Furthermore, the fixed base portion 241 also faces the accommodation space 16a of the vibration damping member 16, and closes the accommodation space 16a from one side in the first direction D1. The other side of the accommodation space 16a in the first direction D1 is closed by the intervening adhesive layer 22 and one side 94a of the wall portion 94, as in the first embodiment. Therefore, the accommodation space 16a in this embodiment is a sealed space.

[0079] The fixed projection 242 protrudes from the other end face 241b of the fixed base portion 241 toward the other side in the first direction D1 and is provided to fit into the housing space 16a of the vibration damping member 16. The fixed projection 242 has a tip surface 242a formed on the other side in the first direction D1.

[0080] The tip surface 242a of the fixed projection 242 abuts against one end surface 141 of the transducer 14. For example, the tip surface 242a of the fixed projection 242 may be joined to one end surface 141 of the transducer 14 by adhesive or the like, or it may simply be pressed against one end surface 141 without being joined. In short, it is sufficient that the transducer 14 is fixed to the fixed projection 242.

[0081] (1) As described above, according to this embodiment, the ultrasonic sensor 10 is equipped with a fixing member 24, which is positioned on one side of the transducer 14 in the first direction D1, and the transducer 14 is fixed to the fixing member 24. The vibration damping member 16 is connected to the fixing member 24. Therefore, the fixing member 24 receives the recoil when the transducer 14 pushes against the wall 94 as the transducer 14 vibrates, making it possible to vibrate the wall 94 firmly.

[0082] Furthermore, in this embodiment, since the vibrator 14 is also fixed to the fixing member 24, vibrations are transmitted from the vibrator 14 to the wall portion 94 via the fixing member 24 and the vibration damping member 16, and vibrations are also transmitted in the reverse order. These vibrations transmitted via the fixing member 24 are absorbed or reflected due to changes in acoustic impedance in the first and second partial spaces 16b and 16c of the vibration damping member 16.

[0083] Furthermore, in the vibration damping member 16, the acoustic impedance of the air in the first and second partial spaces 16b and 16c is different from the acoustic impedance of the predetermined material portion 164. The vibrations transmitted to the vibration damping member 16 between the wall portion 94 and the fixed base portion 241 consist of a first vibration that passes through the first and second partial spaces 16b and 16c, and a second vibration that does not pass through the first and second partial spaces 16b and 16c. The phases of these first and second vibrations are offset from each other due to the difference in acoustic impedance between the air and the predetermined material portion 164 as described above.

[0084] As a result, it is possible to suppress vibrations in both the fixed member 24 and the wall portion 94. In other words, the vibration damping member 16 also has a vibration damping effect that reduces vibrations transmitted between the wall portion 94 and the fixed base portion 241 via the vibration damping member 16, so in this respect as well, it is possible to suppress vibrations in the peripheral portion of the wall portion 94 located around the vibrator-facing portion PA.

[0085] Furthermore, it is preferable that the phase difference between the first vibration and the second vibration exceeds 90° in absolute value. In this embodiment, for example, the shapes of the first and second subspaces 16b and 16c are set by CAE or the like so that the phase difference exceeds 90° in absolute value. CAE stands for Computer-Aided Engineering.

[0086] Here, in order to effectively obtain vibration damping between the wall portion 94 and the fixed base portion 241, it is preferable that the spatial length Lsp of the first and second subspaces 16b and 16c in the first direction D1 satisfies the relationship "Lsp ≥ λ / 2" with respect to the vibration wavelength λ in Figure 10. If this relationship is not satisfied, the vibration of wavelength λ will pass through the first and second subspaces 16b and 16c with little influence from them. In this embodiment, for example, the first and second subspaces 16b and 16c are formed such that the above relationship "Lsp ≥ λ / 2" is satisfied. More specifically, the vibration wavelength λ is the wavelength of the vibration applied from the vibrator 14, transmitted in the first direction D1 between the wall portion 94 and the fixed base portion 241, and passing through the first and second subspaces 16b and 16c. The vibration wavelength λ can be obtained as the interval between the peaks of the vibration waveform Wv, as shown in Figure 10.

[0087] Furthermore, while it is preferable that the spatial length Lsp of the first and second partial spaces 16b and 16c described above, as shown in Figure 8, satisfies the relationship "Lsp ≥ λ / 2", the opposite is true for the spatial width Wsp that the first and second partial spaces 16b and 16c occupy in the radial direction Dr of the vibration damping section in this embodiment. That is, the first and second partial spaces 16b and 16c are formed such that the spatial width Wsp satisfies the relationship "Wsp ≤ λ / 2". This is because even if this relationship "Wsp ≤ λ / 2" is satisfied, the vibration damping effect due to the provision of the first and second partial spaces 16b and 16c can be appropriately obtained. Moreover, the smaller the spatial width Wsp, the easier it is to secure the bonding area between the vibration damping member 16 and the wall portion 94 and to miniaturize the vibration damping member 16. In this embodiment, as in the first embodiment, the spatial length Lsp and spatial width Wsp of the first partial space 16b are in the relationship "Lsp > Wsp", and the spatial length Lsp and spatial width Wsp of the second partial space 16c are also in the relationship "Lsp > Wsp".

[0088] Except as described above, this embodiment is the same as the first embodiment. In this embodiment, the effects obtained from the configuration common to the first embodiment can be obtained in the same way as in the first embodiment.

[0089] (Third embodiment) Next, a third embodiment will be described. This embodiment will primarily describe the differences from the second embodiment described above.

[0090] As shown in Figure 11, in this embodiment, the spatial length Lsp (see Figure 8) of the first partial space 16b of the vibration damping member 16 is longer compared to the second embodiment. Note that the second partial space 16c in this embodiment is the same as the second partial space 16c in the second embodiment.

[0091] Specifically, the first partial space 16b formed in the vibration damping member 16 of this embodiment is formed to be as deep as the first partial space 16b of the second embodiment, penetrating the vibration damping member 16 in the first direction D1. Therefore, when viewed along the first direction D1, the first partial space 16b of this embodiment has the same arrangement and shape as the first partial space 16b of the second embodiment. For example, the first partial space 16b of this embodiment is formed in an annular shape centered on the vibration damping axis CL so as to surround the vibrator 14, similar to the first partial space 16b of the second embodiment.

[0092] Furthermore, in this embodiment, since the first partial space 16b penetrates the vibration damping member 16 in the first direction D1, the first short component 166 does not include the predetermined material portion 164b (see Figure 8), and the first short component 166 is occupied by the first partial space 16b. Therefore, in the vertical cross-section of Figure 11, the predetermined material length Ld1 of the first short component 166 is zero, and thus it is shorter than the predetermined material length Ld1 of the first and second long components 165 and 167 adjacent to the first short component 166. In other words, in this embodiment as well, the first short component 166 is configured as a portion of the vibration damping member 16 in which the predetermined material length Ld1 is partially shortened in the vertical cross-section of Figure 11.

[0093] Furthermore, since the first and second elongated components 165 and 167 of the vibration damping member 16 are separated by the first partial space 16b, the vibration damping member 16, as a single unit, has a two-part structure consisting of a radially inward component and a radially outward component relative to the first partial space 16b.

[0094] (1) As described above, the predetermined material length Ld1 of the first short-shaped component 166 is zero, but since the second short-shaped component 168 has a predetermined material portion 164d, the predetermined material length Ld1 of the second short-shaped component 168 is greater than zero. That is, the predetermined material length Ld1 of the second short-shaped component 168 is different from the predetermined material length Ld1 of the first short-shaped component 166.

[0095] Therefore, it is possible to create a phase difference in vibrations passing through the damping member 16 between the wall portion 94 and the fixed base portion 241 due to differences in acoustic impedance, compared to the case where the first and second short-shaped components 166 and 168 are composed of the same predetermined material length Ld1. For example, among vibrations passing through the damping member 16 in the first direction D1, a phase difference is more likely to occur between vibrations passing through the first short-shaped component 166 and vibrations passing through the second short-shaped component 168. As a result, it is possible to improve the vibration damping effect that attenuates vibrations transmitted through the damping member 16 between the wall portion 94 and the fixed base portion 241.

[0096] Except as described above, this embodiment is the same as the second embodiment. In this embodiment, the effects obtained from the configuration common to the second embodiment can be obtained in the same way as in the second embodiment.

[0097] Although this embodiment is a modified version based on the second embodiment, it is also possible to combine this embodiment with the first embodiment described above.

[0098] (Fourth Embodiment) Next, a fourth embodiment will be described. This embodiment will primarily describe the differences from the third embodiment described above.

[0099] As shown in Figure 12, the vibration damping member 16 of this embodiment is composed of a main body portion 170 and a cover portion 171. In this respect, this embodiment differs from the third embodiment.

[0100] Specifically, the main body portion 170 of the vibration damping member 16 in this embodiment is the same as that of the vibration damping member 16 in the third embodiment. That is, the vibration damping member 16 in this embodiment has a lid portion 171 added to the vibration damping member 16 of the third embodiment. The main body portion 170 is made of a predetermined vibration damping material, similar to the vibration damping member 16 in the third embodiment.

[0101] The cover portion 171 of the vibration damping member 16 is positioned on the other side of the first direction D1 relative to the main body portion 170 and is joined to the main body portion 170 by adhesive or the like. As a result, the other side of the first direction D1 in the first and second partial spaces 16b and 16c is closed by the cover portion 171, so that the first and second partial spaces 16b and 16c become sealed spaces.

[0102] Furthermore, the lid portion 171 also faces the housing space 16a of the vibration damping member 16, and closes the housing space 16a from the other side in the first direction D1. And, as in the third embodiment, one side of the housing space 16a in the first direction D1 is closed by the fixed base portion 241. Therefore, in this embodiment as well, the housing space 16a is a sealed space.

[0103] Furthermore, the other end face 142 of the vibrator 14, which is placed in the housing space 16a, is joined to the lid portion 171 by adhesive or the like. In other words, the vibrator 14 is joined to one side 94a of the wall portion 94 via the lid portion 171 and the intervening adhesive layer 22.

[0104] In this embodiment, the ultrasonic vibrations applied by the transducer 14 are transmitted from the transducer 14 to the lid 171, the intervening adhesive layer 22, and the wall 94 in that order. Therefore, the acoustic impedance of the lid 171 is preferably set to be between the acoustic impedance of the other end face 142 of the transducer 14 and the acoustic impedance of the wall 94. The acoustic impedance of the intervening adhesive layer 22 is preferably set to be between the acoustic impedance of the lid 171 and the acoustic impedance of the wall 94.

[0105] For example, the lid portion 171 is formed in a disc shape having thickness in the first direction D1 and has the same or approximately the same diameter as the main body portion 170. The lid portion 171 may be made of the same predetermined vibration damping material as the main body portion 170, or it may be made of a different constituent material than the main body portion 170. If the lid portion 171 is made of the predetermined vibration damping material, the lid portion 171 is included in the predetermined material portion 164 of the vibration damping member 16.

[0106] Except as described above, this embodiment is the same as the third embodiment. In this embodiment, the effects obtained from the configuration common to the third embodiment can be obtained in the same way as in the third embodiment.

[0107] Although this embodiment is a modified version based on the third embodiment, it is also possible to combine this embodiment with the first or second embodiment described above.

[0108] (Fifth embodiment) Next, a fifth embodiment will be described. This embodiment will primarily describe the differences from the fourth embodiment described above.

[0109] As shown in Figure 13, the main body 170 and the lid 171 (see Figure 12) of the fourth embodiment are a single component made of a predetermined vibration damping material.

[0110] Furthermore, the first partial space 16b and the second partial space 16c each have a groove shape formed by being cut from one side in the first direction D1. Therefore, in the vibration damping member 16, the predetermined material portion 164b of the first short component 166 is arranged in series with respect to the first partial space 16b on the other side in the first direction D1, forming the bottom of the first partial space 16b. Similarly, the predetermined material portion 164d of the second short component 168 is arranged in series with respect to the second partial space 16c on the other side in the first direction D1, forming the bottom of the second partial space 16c.

[0111] Furthermore, in the first and second partial spaces 16b and 16c, one side in the first direction D1 is open for the vibration damping member 16 alone, but is blocked by the fixed base portion 241. As a result, in this embodiment as well, the first and second partial spaces 16b and 16c are sealed spaces.

[0112] Except as described above, this embodiment is the same as the fourth embodiment. In this embodiment, the effects obtained from the configuration common to the fourth embodiment can be obtained in the same way as in the fourth embodiment.

[0113] (Sixth Embodiment) Next, a sixth embodiment will be described. This embodiment will primarily describe the differences from the second embodiment described above.

[0114] As shown in Figure 14, the vibration damping member 16 of this embodiment consists of two parts: a one-sided member 172 and a other-sided member 173. The one-sided member 172 is positioned on one side in the first direction D1 relative to the other-sided member 173, and the one-sided member 172 and the other-sided member 173 are joined to each other by adhesive or the like. For example, the one-sided member 172 and the other-sided member 173 are made of a predetermined vibration damping material, similar to the vibration damping member 16 of the second embodiment.

[0115] Furthermore, the vibration damping member 16 has a housing space cover portion 173a that constitutes a part of the other side member 173. The housing space cover portion 173a is formed in the shape of a flat plate, for example, having thickness in the first direction D1.

[0116] The lid portion 173a of the housing space is positioned on the other side in the first direction D1 relative to the housing space 16a of the vibration damping member 16, and faces the housing space 16a. The lid portion 173a closes the housing space 16a from the other side in the first direction D1.

[0117] Furthermore, the other end face 142 of the vibrator 14, which is placed within the housing space 16a, is joined to the housing space lid 173a by adhesive or the like. In other words, the vibrator 14 is joined to one side 94a of the wall portion 94 via the housing space lid 173a and the intervening adhesive layer 22.

[0118] In this embodiment, the ultrasonic vibrations applied by the transducer 14 are transmitted from the transducer 14 to the housing space lid 173a, the intervening adhesive layer 22, and the wall portion 94 in that order. Therefore, the acoustic impedance of the housing space lid 173a is preferably set to be between the acoustic impedance of the other end face 142 of the transducer 14 and the acoustic impedance of the wall portion 94. The acoustic impedance of the intervening adhesive layer 22 is preferably set to be between the acoustic impedance of the housing space lid 173a and the acoustic impedance of the wall portion 94.

[0119] As described above, the vibration damping member 16 of this embodiment is composed of one side member 172 and the other side member 173, so each component 165 to 169 of the vibration damping member 16 is provided so as to span both the one side member 172 and the other side member 173. The first partial space 16b of the vibration damping member 16 is formed so as to span both the one side member 172 and the other side member 173. On the other hand, the second partial space 16c is formed in the other side member 173, and the one side member 172 faces the second partial space 16c so as to close one side of the first direction D1 in the second partial space 16c.

[0120] In the first short-shaped component 166, predetermined material portions 164b are arranged on both one side and the other side of the first direction D1 with respect to the first partial space 16b. In the second short-shaped component 168, predetermined material portions 164d are arranged on both one side and the other side of the first direction D1 with respect to the second partial space 16c.

[0121] Therefore, the predetermined material length Ld1 of the first short-shaped component 166 is the sum of the length Ld1a of the predetermined material portion 164b located on one side of the first direction D1 of the first short-shaped component 166 and the length Ld1b of the predetermined material portion 164b located on the other side of the first direction D1. Similarly, the predetermined material length Ld1 of the second short-shaped component 168 is the sum of the length Ld1a of the predetermined material portion 164d located on one side of the second short-shaped component 168 in the first direction D1 and the length Ld1b of the predetermined material portion 164d located on the other side of the first direction D1.

[0122] Except as described above, this embodiment is the same as the second embodiment. In this embodiment, the effects obtained from the configuration common to the second embodiment can be obtained in the same way as in the second embodiment.

[0123] Although this embodiment is a modified version based on the second embodiment, it is also possible to combine this embodiment with the first embodiment described above.

[0124] (Seventh Embodiment) Next, a seventh embodiment will be described. This embodiment will primarily describe the differences from the second embodiment described above.

[0125] As shown in Figure 15, in the vibration damping member 16 of this embodiment, a first dissimilar material portion 174 is provided in place of the first partial space 16b (see Figure 8) of the second embodiment, and a second dissimilar material portion 175 is provided in place of the second partial space 16c of the second embodiment. Therefore, the first dissimilar material portion 174 is included in the first short-shaped component 166, and the second dissimilar material portion 175 is included in the second short-shaped component 168.

[0126] The predetermined material portion 164 of the vibration damping member 16 in this embodiment is the same as the predetermined material portion 164 of the vibration damping member 16 in the second embodiment. Therefore, the predetermined vibration damping material constituting the predetermined material portion 164 in this embodiment is PBT.

[0127] The first dissimilar material portion 174 in this embodiment is obtained by filling the first partial space 16b of the second embodiment with a dissimilar material member (specifically, silicone) which has an acoustic impedance different from that of the PBT used as the predetermined vibration damping material. Therefore, the shape and arrangement of the first dissimilar material portion 174 are the same as those of the first partial space 16b in the second embodiment.

[0128] For example, the first dissimilar material portion 174 is formed between two predetermined material portions 164a and 164c that are spaced apart in the radial direction Dr of the vibration damping portion in the longitudinal section of Figure 15, similar to the first partial space 16b of the second embodiment. The first dissimilar material portion 174 is arranged in series with respect to the predetermined material portion 164b of the first short-shaped component 166 on the other side in the first direction D1.

[0129] The second dissimilar material portion 175 in this embodiment is obtained by filling the second partial space 16c of the second embodiment with silicone as a dissimilar material member. Therefore, the shape and arrangement of the second dissimilar material portion 175 are the same as those of the second partial space 16c of the second embodiment.

[0130] For example, the second dissimilar material portion 175 is formed between two predetermined material portions 164c and 164e that are spaced apart in the radial direction Dr of the vibration damping portion in the longitudinal section of Figure 15, similar to the second partial space 16c of the second embodiment. The second dissimilar material portion 175 is arranged in series with respect to the predetermined material portion 164d of the second short-shaped component 168 on the other side in the first direction D1.

[0131] Furthermore, since the Young's modulus of PBT is approximately 9000 MPa and that of silicone is approximately 5 MPa, the first and second dissimilar material sections 174 and 175 are significantly softer than the predetermined material section 164. In addition, the acoustic impedance of PBT and the acoustic impedance of silicone are different from each other.

[0132] As described above, the first and second dissimilar material sections 174 and 175 are configured such that the lengths La of the first and second dissimilar material sections 174 and 175 in the first direction D1 are the same as the spatial lengths Lsp of the first and second partial spaces 16b and 16c in the second embodiment (see Figure 8). Furthermore, the radial width Wa occupied by the first and second dissimilar material sections 174 and 175 in the radial direction Dr of the vibration damping section is the same as the spatial width Wsp of the first and second partial spaces 16b and 16c in the second embodiment (see Figure 8).

[0133] Therefore, just as the relationship "Lsp≧λ / 2" is satisfied in the second embodiment, the relationship "La≧λ / 2" is satisfied in this embodiment, for example. Also, just as the relationship "Wsp≦λ / 2" is satisfied in the second embodiment, the relationship "Wa≦λ / 2" is satisfied in this embodiment, for example. In the relationship, the wavelength λ is, more specifically, the wavelength of vibration applied from the oscillator 14, transmitted in the first direction D1 between the wall portion 94 and the fixed base portion 241, and passing through the first and second dissimilar material portions 174 and 175. The wavelength λ of this vibration can be obtained as the interval between the peaks of the vibration waveform Wv shown in Figure 10, similar to the second embodiment.

[0134] Furthermore, just as the relationship "Lsp > Wsp" holds in the second embodiment, in this embodiment, for example, the length La and radial width Wa of the first dissimilar material portion 174 are in the relationship "La > Wa", and the length La and radial width Wa of the second dissimilar material portion 175 are in the relationship "La > Wa".

[0135] The first dissimilar material portion 174 has one end 174a provided on one side of the first direction D1 and the other end 174b provided on the other side of the first direction D1. The second dissimilar material portion 175 has one end 175a provided on one side of the second dissimilar material portion 175 and the other end 175b provided on the other side of the first direction D1.

[0136] Furthermore, in this embodiment, in the first direction D1, the positions of the other ends 174b and 175b of the first and second dissimilar material portions 174 and 175 are the same as the positions of the other end face 162 of the vibration damping member 16. That is, the distance between the other end face 162 of the vibration damping member 16 and the other ends 174b and 175b of the first and second dissimilar material portions 174 and 175 in the first direction D1 is zero. Therefore, the distance between the other end face 162 of the vibration damping member 16 and the other end 174b of the first dissimilar material portion 174 in the first direction D1 is smaller than the length La of the first dissimilar material portion 174 in the first direction D1. And the distance between the other end face 162 of the vibration damping member 16 and the other end 175b of the second dissimilar material portion 175 in the first direction D1 is smaller than the length La of the second dissimilar material portion 175 in the first direction D1.

[0137] (1) As described above, according to this embodiment, the first short component 166 has a first dissimilar material component 174, and the second short component 168 has a second dissimilar material component 175. The first and second dissimilar material components 174 and 175 are composed of dissimilar material members having different acoustic impedances than the predetermined material component 164. In the longitudinal section of Figure 15, the first dissimilar material component 174 is formed between two predetermined material components 164a and 164c that are spaced apart in the radial direction Dr of the vibration damping component, and the second dissimilar material component 175 is formed similarly.

[0138] Even in this manner, as in the second embodiment, it is possible to suppress vibrations in the peripheral areas located around the vibrator-facing portion PA (see Figure 6) of the wall portion 94. For example, vibrations transmitted from the vibrator 14 to the wall portion 94 via the fixing member 24 and the vibration damping member 16 are absorbed or reflected due to the difference in acoustic impedance between the first and second dissimilar material portions 174 and 175 and the predetermined material portions 164b and 164d of the vibration damping member 16. Due to the difference in acoustic impedance, a difference in sound velocity occurs between vibrations passing through the first and second dissimilar material portions 174 and 175 and vibrations that do not pass through the first and second dissimilar material portions 174 and 175, and as the phases of these vibrations shift relative to each other, they attenuate each other.

[0139] Furthermore, since the dissimilar material members constituting the first and second dissimilar material parts 174 and 175 are silicone, they are solid. Therefore, compared to the case where the first and second dissimilar material parts 174 and 175 replace the first and second partial spaces 16b and 16c (see Figure 8), it is possible to prevent the adhesive of the intervening adhesive layer 22 from penetrating into the area occupied by the first and second dissimilar material parts 174 and 175. Moreover, compared to the case where the first and second dissimilar material parts 174 and 175 replace the first and second partial spaces 16b and 16c, it is possible to prevent the progression of aging deterioration caused by changes in air volume, condensation, etc.

[0140] Furthermore, according to this embodiment, the distance between the other end face 162 of the vibration damping member 16 and the other end 174b of the first dissimilar material portion 174 in the first direction D1 is smaller than the length La of the first dissimilar material portion 174 in the first direction D1. The same applies to the second dissimilar material portion 175. Therefore, compared to, for example, the case where the distance between the other end face 162 and the other ends 174b and 175b of the dissimilar material portions 174 and 175 is larger than the length La of the dissimilar material portions 174 and 175, it is possible to increase the difference in rigidity between the high-flexural-rigidity and low-flexural-rigidity parts of the wall portion 94 to which the vibration damping member 16 is attached. As a result, it is possible to further attenuate vibrations transmitted from the transducer-facing portion PA (see Figure 6) to the surrounding portion of the wall portion 94, and vibrations transmitted from the surrounding portion to the transducer-facing portion PA.

[0141] Except as described above, this embodiment is the same as the second embodiment. In this embodiment, the effects obtained from the configuration common to the second embodiment can be obtained in the same way as in the second embodiment.

[0142] Although this embodiment is a modification based on the second embodiment, it is also possible to combine this embodiment with any of the first, third to sixth embodiments described above.

[0143] (Eighth embodiment) Next, the eighth embodiment will be described. This embodiment will primarily describe the differences from the seventh embodiment described above.

[0144] As shown in Figure 16, in this embodiment, compared to the seventh embodiment, the materials constituting the first and second dissimilar material portions 174 and 175 of the vibration damping member 16 are replaced from silicone to aluminum. That is, the first dissimilar material portion 174 in this embodiment is the first partial space 16b of the second embodiment (see Figure 8) filled with aluminum. And the second dissimilar material portion 175 in this embodiment is the second partial space 16c of the second embodiment (see Figure 8) filled with aluminum.

[0145] The Young's modulus of PBT is approximately 9000 MPa, while that of aluminum is approximately 70000 MPa. Therefore, the first and second dissimilar material sections 174 and 175 are significantly harder than the predetermined material section 164. Furthermore, the acoustic impedance of PBT and the acoustic impedance of aluminum are different. Consequently, the aluminum constituting the first and second dissimilar material sections 174 and 175 corresponds to a dissimilar material component having a different acoustic impedance than the PBT used as the predetermined vibration damping material.

[0146] Except as described above, this embodiment is the same as the seventh embodiment. In this embodiment, the effects obtained from the configuration common to the seventh embodiment can be obtained in the same way as in the seventh embodiment.

[0147] (Ninth Embodiment) Next, the ninth embodiment will be described. This embodiment will primarily describe the differences from the seventh embodiment described above.

[0148] As shown in Figure 17, in this embodiment, compared to the seventh embodiment, the material constituting the second dissimilar material portion 175 of the vibration damping member 16 is replaced from silicone to aluminum. That is, in this embodiment, the second dissimilar material portion 175 is the second partial space 16c (see Figure 8) of the second embodiment filled with aluminum. On the other hand, the first dissimilar material portion 174 of this embodiment is the same as in the seventh embodiment.

[0149] In other words, the first dissimilar material portion 174 of this embodiment is made of a first member (specifically, silicone) having an acoustic impedance different from that of the PBT used as the predetermined vibration damping material. The second dissimilar material portion 175 is made of a second member (specifically, aluminum) having an acoustic impedance different from both the predetermined vibration damping material and the first member. Both the first and second members are solids, but they are made of different materials.

[0150] (1) Accordingly, the generation of a phase difference due to the difference in acoustic impedance in vibrations passing through the damping member 16 between the wall portion 94 and the fixed base portion 241 can be promoted compared to the case where the first dissimilar material portion 174 and the second dissimilar material portion 175 are made of the same material, for example. For example, among the vibrations passing through the damping member 16 in the first direction D1, a phase difference is more likely to occur between the vibrations passing through the first short-shaped component portion 166 and the vibrations passing through the second short-shaped component portion 168. As a result, it is possible to improve the vibration damping effect that reduces vibrations transmitted through the damping member 16 between the wall portion 94 and the fixed base portion 241.

[0151] Except as described above, this embodiment is the same as the seventh embodiment. In this embodiment, the effects obtained from the configuration common to the seventh embodiment can be obtained in the same way as in the seventh embodiment.

[0152] (Tenth embodiment) Next, a tenth embodiment will be described. This embodiment will primarily describe the differences from the second embodiment described above.

[0153] As shown in Figure 18, the second partial space 16c in this embodiment has a groove shape formed by being cut from the other side of the first direction D1, similar to the second embodiment. However, in this embodiment, the spatial length Lsp of the second partial space 16c is longer compared to the second embodiment. The first partial space 16b in this embodiment is the same as the first partial space 16b in the second embodiment.

[0154] Therefore, the predetermined material length Ld1 of the second short-shaped component 168 is different from the predetermined material length Ld1 of the first short-shaped component 166. As a result, in this embodiment as well as in the third embodiment, for example, among the vibrations passing through the vibration damping member 16 in the first direction D1 between the wall 94 and the fixed base 241, a phase difference is likely to occur between the vibrations passing through the first short-shaped component 166 and the vibrations passing through the second short-shaped component 168. As a result, it is possible to improve the vibration damping effect that dampens vibrations transmitted through the vibration damping member 16 between the wall 94 and the fixed base 241.

[0155] Except as described above, this embodiment is the same as the second embodiment. In this embodiment, the effects obtained from the configuration common to the second embodiment can be obtained in the same way as in the second embodiment.

[0156] Although this embodiment is a modification based on the second embodiment, it is also possible to combine this embodiment with any of the fourth to ninth embodiments described above.

[0157] (11th embodiment) Next, the eleventh embodiment will be described. This embodiment will primarily describe the differences from the second embodiment described above.

[0158] As shown in Figure 19, the shape of the fixing member 24 in this embodiment differs from that of the second embodiment.

[0159] Specifically, the fixing member 24 of this embodiment has a fixing base portion 241, a fixing projection portion 242, and a wall connecting portion 243. The fixing base portion 241, the fixing projection portion 242, and the wall connecting portion 243 are integrally constructed. In this embodiment, the portion of the fixing member 24 consisting of the fixing base portion 241 and the fixing projection portion 242 corresponds to the fixing portion of this disclosure.

[0160] The fixed base portion 241 in this embodiment is a disc shape concentric with the vibration damping member 16, similar to the second embodiment, but it extends outward in the radial direction Dr of the vibration damping portion compared to the vibration damping member 16. In other words, the outer diameter of the fixed base portion 241 is larger than the outer diameter of the vibration damping member 16.

[0161] The wall connecting portion 243 is provided between the fixed base portion 241 and the wall portion 94, and fixes the fixed base portion 241 to the wall portion 94 without the need for the vibration damping member 16 and the vibrator 14. The wall connecting portion 243 has a cylindrical shape that extends from the peripheral portion of the fixed base portion 241 to the other side in the first direction D1. For example, the wall connecting portion 243 has a cylindrical shape that is concentric with the vibration damping member 16.

[0162] The wall connection portion 243 is located outside the vibration damping member 16 and the intervening adhesive layer 22 in the radial direction Dr of the vibration damping portion. That is, the vibrator 14, the vibration damping member 16, and the intervening adhesive layer 22 are housed within the space formed inside the wall connection portion 243.

[0163] The wall connecting portion 243 has a tip surface 243a formed on the other side of the wall connecting portion 243 in the first direction D1. This tip surface 243a faces one side 94a of the wall portion 94 and is joined to that side 94a by adhesive or the like. Therefore, the fixing member 24 is fixed to the wall portion 94 not only via the vibration damping member 16 and the intervening adhesive layer 22, but also to the wall portion 94 by the joining of the tip surface 243a of the wall connecting portion 243 to the wall portion 94. For example, the tip surface 243a of the wall connecting portion 243 is joined to one side 94a of the wall portion 94 in a ring-like continuous manner around the vibration damping member 16.

[0164] Except as described above, this embodiment is the same as the second embodiment. In this embodiment, the effects obtained from the configuration common to the second embodiment can be obtained in the same way as in the second embodiment.

[0165] Although this embodiment is a modification based on the second embodiment, it is also possible to combine this embodiment with any of the third to tenth embodiments described above.

[0166] (12th embodiment) Next, a twelfth embodiment will be described. This embodiment will primarily describe the differences from the first embodiment described above.

[0167] As shown in Figure 20, the first partial space 16b and the second partial space 16c each extend to surround the vibrator 14 (see Figure 3) in a direction view along the first direction D1, similar to the first embodiment. However, unlike the first embodiment, the first partial space 16b and the second partial space 16c in this embodiment are interrupted in a portion of the circumferential direction Dc around the vibration damping axis CL. In the following description, the circumferential direction Dc around the vibration damping axis CL may also be referred to as the vibration damping circumferential direction Dc.

[0168] Specifically, the vibration damping member 16 has a first connecting portion 176a and a second connecting portion 176b. For example, these first connecting portion 176a and second connecting portion 176b are made of the same predetermined vibration damping material as the first, second, and third elongated components 165, 167, and 169.

[0169] The first connecting portion 176a is provided between the first elongated component 165 and the second elongated component 167, and connects the first elongated component 165 and the second elongated component 167. Therefore, the first partial space 16b has a shape that is interrupted in part in the circumferential direction Dc of the vibration damping portion.

[0170] The second connecting portion 176b is provided between the second elongated component 167 and the third elongated component 169, and connects the second elongated component 167 and the third elongated component 169. Therefore, the second partial space 16c has a shape that is interrupted in part in the circumferential direction Dc of the vibration damping portion.

[0171] Except as described above, this embodiment is the same as the first embodiment. In this embodiment, the effects obtained from the configuration common to the first embodiment can be obtained in the same way as in the first embodiment.

[0172] Although this embodiment is a modification based on the first embodiment, it is also possible to combine this embodiment with any of the second to eleventh embodiments described above.

[0173] (13th Embodiment) Next, the 13th embodiment will be described. This embodiment will primarily describe the differences from the 7th embodiment described above.

[0174] As shown in Figure 21, the vibration damping member 16 has connecting dissimilar material sections 177. These connecting dissimilar material sections 177 are made of the same dissimilar material (specifically, silicone) as the first and second dissimilar material sections 174 and 175. For example, multiple connecting dissimilar material sections 177 are provided and arranged at equal pitches in the circumferential direction Dc of the vibration damping section.

[0175] Each of the multiple connecting dissimilar material sections 177 is provided between the first dissimilar material section 174 and the second dissimilar material section 175, connecting the first dissimilar material section 174 and the second dissimilar material section 175. In other words, a part of the first dissimilar material section 174 and a part of the second dissimilar material section 175 are connected via the connecting dissimilar material section 177, which is a part composed of dissimilar material members. Each of the multiple connecting dissimilar material sections 177 is formed to cross the second elongated component 167 in the radial direction Dr of the vibration damping section.

[0176] (1) As described above, according to this embodiment, a part of the first dissimilar material section 174 and a part of the second dissimilar material section 175 are connected via a connecting dissimilar material section 177 made of dissimilar material members. Therefore, when filling the first and second dissimilar material sections 174 and 175 with dissimilar material members such as silicone in the manufacturing process of the vibration damping member 16, there are the following advantages. That is, if the dissimilar material member is injected into one of the locations where the first and second dissimilar material sections 174 and 175 are provided, the dissimilar material member will spread to the other location as well. This advantage makes it possible to improve the workability when filling the vibration damping member 16 with dissimilar material members that make up the first and second dissimilar material sections 174 and 175 compared to when the first and second dissimilar material sections 174 and 175 are separated from each other.

[0177] Except as described above, this embodiment is the same as the seventh embodiment. In this embodiment, the effects obtained from the configuration common to the seventh embodiment can be obtained in the same way as in the seventh embodiment.

[0178] Although this embodiment is a modification based on the seventh embodiment, it is also possible to combine this embodiment with any of the first to sixth or eighth to eleventh embodiments described above.

[0179] (14th Embodiment) Next, a 14th embodiment will be described. This embodiment will primarily describe the differences from the first embodiment described above.

[0180] As shown in Figure 22, in this embodiment, the vibration damping member 16 has multiple short components 178 instead of the first and second short components 166 and 168 (see Figure 3) of the first embodiment. Furthermore, the vibration damping member 16 has multiple long components 179 instead of the first, second and third long components 165, 167 and 169 of the first embodiment.

[0181] Each of the multiple short-shaped components 178 in this embodiment has a partial space 16d formed therein, which replaces the first and second partial spaces 16b and 16c (see Figure 3) of the first embodiment. For example, the partial space 16d has a concave shape formed so as to be recessed from one side to the other in the first direction D1, and the spatial length Lsp (see Figure 3) of the partial space 16d is the same as that of the first and second partial spaces 16b and 16c. Therefore, the cross-sectional shape that appears in the cross section along the first direction D1 is the same for each of the multiple short-shaped components 178 in this embodiment as it is for the first and second short-shaped components 166 and 168 of the first embodiment.

[0182] However, with respect to the shape as shown in a view along the first direction D1, the multiple short components 178 of this embodiment differ from the first and second short components 166 and 168 of the first embodiment. Furthermore, with respect to the shape as shown in a view along the first direction D1, the multiple long components 179 also differ from the first, second and third long components 165, 167 and 169 of the first embodiment.

[0183] Specifically, each of the multiple short components 178 forms a rectangular shape when viewed along the first direction D1, and each of the multiple long components 179 also forms a rectangular shape when viewed along the first direction D1. Furthermore, each of the multiple partial spaces 16d also forms a rectangular shape when viewed along the first direction D1. The multiple short components 178 and the multiple long components 179 are arranged alternately in the second direction D2 and also alternately in the third direction D3.

[0184] Therefore, each of the multiple short components 178 is configured as a part in the vibration damping member 16 in which a predetermined material length Ld1 (see Figure 3) is partially shortened in the longitudinal cross-section corresponding to Figure 3. The multiple long components 179 are components in which the predetermined material length Ld1 is longer than that of the short components 178.

[0185] Except as described above, this embodiment is the same as the first embodiment. In this embodiment, the effects obtained from the configuration common to the first embodiment can be obtained in the same way as in the first embodiment.

[0186] Although this embodiment is a modification based on the first embodiment, it is also possible to combine this embodiment with any of the second to eleventh embodiments described above.

[0187] (15th Embodiment) Next, the 15th embodiment will be described. This embodiment will primarily describe the differences from the 14th embodiment described above.

[0188] As shown in Figure 23, in the vibration damping member 16 of this embodiment, multiple dissimilar material portions 180 are provided instead of the multiple partial spaces 16d (see Figure 22) of the 14th embodiment. Therefore, these dissimilar material portions 180 are included in the short-shaped component portion 178.

[0189] The dissimilar material portion 180 in this embodiment is obtained by filling the partial space 16d of the 14th embodiment with a dissimilar material member (specifically, silicone) which has a different acoustic impedance from the PBT used as the predetermined vibration damping material. Among the multiple dissimilar material portions 180, adjacent dissimilar material portions 180 are connected to each other in a portion of their respective parts. For example, at the vertices of the rectangular shape of the dissimilar material portion 180 that appears when viewed along the first direction D1 (i.e., the dissimilar material portion 180 shown in Figure 23), adjacent dissimilar material portions 180 are connected to each other. Except for this, the shape and arrangement of the dissimilar material portions 180 in this embodiment are the same as those of the partial space 16d in the 14th embodiment.

[0190] For example, the dissimilar material portion 180 is formed between two predetermined material portions 164 (see Figure 3) that are spaced apart in the second direction D2 in a longitudinal cross-section corresponding to Figure 3, similar to the partial space 16d of the 14th embodiment. The dissimilar material portion 180 is arranged in series with respect to the portion of the predetermined material portion 164 that belongs to the short-shaped component 178, on the other side in the first direction D1.

[0191] As described above, according to this embodiment, among the multiple dissimilar material parts 180, adjacent dissimilar material parts 180 are connected to each other in a portion of their respective parts. Therefore, similar to the 13th embodiment, in the manufacturing process of the vibration damping member 16, it is possible to improve the workability when filling the vibration damping member 16 with the dissimilar material members constituting the dissimilar material parts 180, compared to the case where the dissimilar material parts 180 are separated from each other.

[0192] Except as described above, this embodiment is the same as the 14th embodiment. In this embodiment, the effects obtained from the configuration common to the 14th embodiment can be obtained in the same way as in the 14th embodiment.

[0193] (16th Embodiment) Next, the 16th embodiment will be described. This embodiment will primarily describe the differences from the 14th embodiment described above.

[0194] As shown in Figure 24, in this embodiment, the shapes of the short component 178, the long component 179, and the partial space 16d that appear when viewed along the first direction D1 are different from those of the 14th embodiment.

[0195] Specifically, in a view along the first direction D1, the short component 178, the long component 179, and the partial space 16d each extend in an arc shape centered on the vibration damping axis CL. The multiple short component 178 and multiple long component 179 are arranged alternately in the radial direction Dr (see Figure 3) of the vibration damping, and also alternately in the circumferential direction Dc of the vibration damping. Therefore, the multiple partial spaces 16d are arranged in both the radial direction Dr and the circumferential direction Dc of the vibration damping, with a predetermined material portion 164 (see Figure 3) in between them.

[0196] Except as described above, this embodiment is the same as the 14th embodiment. In this embodiment, the effects obtained from the configuration common to the 14th embodiment can be obtained in the same way as in the 14th embodiment.

[0197] Although this embodiment is a modification based on the 14th embodiment, it is also possible to combine this embodiment with any of the first to 11th embodiments described above.

[0198] (Other embodiments) (1) In each of the embodiments described above, the ultrasonic sensor 10 is attached to a part of the resin bumper 93 as shown in Figure 1, but this is just one example. For example, the ultrasonic sensor 10 may be attached to a part of a metal plate such as a vehicle body panel 92.

[0199] (2) In each of the embodiments described above, as shown in Figure 2, the transducer 14 has both a transmitting function that converts electrical signals into ultrasonic vibrations and emits those ultrasonic vibrations, and a receiving function that converts the ultrasonic vibrations received by the transducer 14 into electrical signals and outputs those electrical signals. However, this is just one example. For example, the transducer 14 may have one of the transmitting and receiving functions but not the other.

[0200] (3) In each of the embodiments described above, for example, the vibration transmitted and received by the transducer 14 in Figures 2 and 3 is ultrasonic vibration, but vibrations with a lower frequency than ultrasonic vibration may also be used.

[0201] (4) In each of the embodiments described above, for example as shown in Figure 3, the housing space 16a of the vibration damping member 16 in which the vibrator 14 is arranged is a space filled with air, but this is just one example. For example, the housing space 16a may be filled with a material that does not hinder the vibration of the vibrator 14, such as foam material.

[0202] (5) In each of the embodiments described above, for example, the transducer 14 in Figures 2 and 3 has a driving element composed of, for example, multiple stacked piezoelectric elements in order to perform the function of converting ultrasonic vibrations and electrical signals from one to the other, but this is just one example. For example, the driving element may be composed of a single piezoelectric element. Furthermore, the driving element may be composed of components other than piezoelectric elements as long as they generate vibrations.

[0203] (6) In the second to eleventh embodiments described above, the fixing member 24 is configured as a single component, for example, as shown in Figure 8, but this is just one example. For example, the fixing member 24 may be configured by assembling multiple components. The same applies to the vibration damping member 16, for example.

[0204] (7) The present invention is not limited to the embodiments described above and can be implemented in various modified forms. Furthermore, the embodiments described above are not unrelated to each other and can be combined as appropriate, except in cases where the combination is clearly impossible.

[0205] Furthermore, it goes without saying that, in each of the above embodiments, the elements constituting the embodiment are not necessarily essential unless explicitly stated to be particularly essential or unless they are clearly considered essential in principle. Also, in each of the above embodiments, when numerical values ​​such as the number, numerical values, quantities, or ranges of the components of the embodiment are mentioned, the embodiment is not limited to those specific numbers unless explicitly stated to be particularly essential or unless it is clearly limited to a specific number in principle. Also, in each of the above embodiments, when the material, shape, positional relationship, etc. of the components are mentioned, the embodiment is not limited to those material, shape, positional relationship, etc. unless explicitly stated or unless it is clearly limited to a specific material, shape, positional relationship, etc. in principle.

[0206] (Features of the present invention) [Claim 1] An object detection device (10) is attached to a wall portion (94) having thickness in one direction (D1), A vibrator (14) is connected to one side (94a) of the wall portion so as to transmit vibrations between the one side and the one side formed on one side in the one direction, The wall portion is attached to one of its surfaces and formed on that surface to surround the vibrator, and comprises a vibration damping section (16) made of a predetermined material, The oscillator has a conversion function that converts one of the vibrations generated in the oscillator and an electrical signal into the other. The vibration damping section has short components (166, 168, 178), The short-shaped component is configured such that, in a longitudinal cross-section passing through the center of the vibrator and parallel to the one direction, the length (Ld1) occupied by a predetermined material portion (164) in that one direction is partially shortened within the vibration damping portion. The object detection device, wherein the predetermined material portion is the part of the vibration damping section that is made of the predetermined material. [Claim 2] The vibrator is provided with fixing parts (24, 241, 242) arranged on one side in the one direction, to which the vibrator is fixed. The object detection device according to claim 1, wherein the vibration damping part is connected to the fixed part. [Claim 3] The short-shaped component has dissimilar material parts (174, 175, 180) made of a material having an acoustic impedance different from the predetermined material. The object detection device according to claim 1 or 2, wherein the dissimilar material portion is formed between two predetermined material portions arranged at intervals in a direction perpendicular to the one direction (Dr, D2, D3) in the longitudinal cross-section. [Claim 4] Multiple of the aforementioned short-shaped components are provided. Multiple parts made of different materials are also provided. The plurality of dissimilar material parts include a first dissimilar material part (174) and a second dissimilar material part (175). The first dissimilar material portion is composed of a first member having an acoustic impedance different from that of the predetermined material. The object detection device according to claim 3, wherein the second dissimilar material portion is composed of a second member having an acoustic impedance different from both the predetermined material and the first member. [Claim 5] Multiple of the aforementioned short-shaped components are provided. The object detection device according to any one of claims 1 to 3, wherein the plurality of short-shaped components include a first short-shaped component (166) and a second short-shaped component (168) whose length in one direction is different from that of the first short-shaped component. [Claim 6] The object detection device according to any one of claims 1 to 5, wherein the short-shaped component is arranged to surround the vibrator when viewed in a direction along the one direction. [Claim 7] Multiple of the aforementioned short-shaped components are provided. The plurality of short-shaped components include a first short-shaped component (166) and a second short-shaped component (168) arranged to surround the vibrator when viewed in a direction along the one direction, The first short-shaped component is positioned on the inner circumference side relative to the second short-shaped component, The first short-shaped component and the second short-shaped component each have a dissimilar material component (174, 175) made of a dissimilar material having an acoustic impedance different from the predetermined material, The respective dissimilar material portions of the first and second short-shaped components are formed between two predetermined material portions that are spaced apart in a direction perpendicular to the one direction (Dr) in the longitudinal cross-section. The object detection device according to claim 1 or 2, wherein a portion of the dissimilar material portion (174) of the first short-shaped component and a portion of the dissimilar material portion (175) of the second short-shaped component are connected via a portion (177) made of the dissimilar material member. [Explanation of symbols]

[0207] 10. Ultrasonic sensor (object detection device) 14. Oscillator 16. Vibration damping member (vibration damping part) 94 Wall 94a One side 164 Predetermined material part 166 First short component (short component) 168 Second short component (short component) 178 Short component D1 1st direction (one direction)

Claims

1. An object detection device (10) is attached to a wall portion (94) having thickness in one direction (D1), A vibrator (14) is connected to one side (94a) of the wall portion so as to transmit vibrations between the vibrator and the one side (94a) formed on one side in the one direction, The wall portion is attached to one of its surfaces, and a vibration damping section (16) is formed on that surface to surround the vibrator and is made of a predetermined material. The oscillator has a conversion function that converts one of the vibrations generated in the oscillator and an electrical signal into the other. The vibration damping section has short components (166, 168, 178), The short-shaped component is configured such that, in a longitudinal cross-section passing through the center of the vibrator and parallel to the one direction, the length (Ld1) occupied by a predetermined material portion (164) in that one direction is partially shortened within the vibration damping portion. The object detection device, wherein the predetermined material portion is the part of the vibration damping section that is made of the predetermined material.

2. The vibrator is provided with fixing parts (24, 241, 242) arranged on one side in the one direction, to which the vibrator is fixed. The object detection device according to claim 1, wherein the vibration damping part is connected to the fixed part.

3. The short-shaped component has dissimilar material parts (174, 175, 180) made of a material having an acoustic impedance different from the predetermined material, The object detection device according to claim 1 or 2, wherein the dissimilar material portion is formed between two predetermined material portions arranged at intervals in a direction perpendicular to the one direction (Dr, D2, D3) in the longitudinal cross-section.

4. Multiple of the aforementioned short-shaped components are provided. Multiple parts made of different materials are also provided. The plurality of dissimilar material parts include a first dissimilar material part (174) and a second dissimilar material part (175). The first dissimilar material portion is composed of a first member having an acoustic impedance different from that of the predetermined material. The object detection device according to claim 3, wherein the second dissimilar material portion is composed of a second member having an acoustic impedance different from both the predetermined material and the first member.

5. Multiple of the aforementioned short-shaped components are provided. The object detection device according to claim 1 or 2, wherein the plurality of short-shaped components include a first short-shaped component (166) and a second short-shaped component (168) whose length in one direction is different from that of the first short-shaped component.

6. The object detection device according to claim 1 or 2, wherein the short-shaped component is arranged to surround the vibrator when viewed in a direction along the one direction.

7. Multiple of the aforementioned short-shaped components are provided. The plurality of short-shaped components include a first short-shaped component (166) and a second short-shaped component (168) arranged to surround the vibrator when viewed in a direction along the one direction, The first short-shaped component is positioned on the inner circumference side relative to the second short-shaped component, The first short-shaped component and the second short-shaped component each have a dissimilar material component (174, 175) made of a dissimilar material member having an acoustic impedance different from the predetermined material, The different material portions of the first short component and the second short component are formed in the longitudinal cross-section between two predetermined material portions that are spaced apart in a direction perpendicular to the one direction (Dr), The object detection device according to claim 1 or 2, wherein a portion of the dissimilar material portion (174) of the first short-shaped component and a portion of the dissimilar material portion (175) of the second short-shaped component are connected via a portion (177) made of the dissimilar material member.

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