Ultrasonic sensor and vibration absorber

Abstract

The present invention provides an ultrasonic sensor and a vibration absorber. The vibration absorber (5) has a large diameter portion (58) and a small diameter portion (59). The large diameter portion is arranged to contact an ultrasonic microphone (4) and a sensor mounting device (7) and is clamped between the ultrasonic microphone and the sensor mounting device. The small diameter portion, whose outer diameter is formed smaller than the large diameter portion with respect to a central axis (CL) as the center, is arranged adjacent to the large diameter portion in the circumferential direction surrounding the central axis. A pair of large diameter portions are arranged opposite to each other across the central axis. A pair of small diameter portions are arranged opposite to each other across the central axis. The vibration absorber is constructed so that the arrangement direction of a pair of large diameter portions across the central axis and the arrangement direction of a pair of small diameter portions across the central axis are orthogonal to each other.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based on Japanese Patent Application No. 2020-75595 filed on April 21, 2020, the contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to an ultrasonic sensor and a vibration absorber provided in the ultrasonic sensor. Background Art

[0004] The ultrasonic sensor described in Patent Document 1 is used as a rear sonar or a corner sonar by being mounted on a bumper of a vehicle. Specifically, a sensor body integrated with a frame and a vibration suppression component is inserted from the outside of the bumper into a hole in the bumper. The frame is a cylindrical component having a hollow portion and is made of a synthetic resin or the like. Thereafter, a retainer is mounted on the back side of the bumper. The retainer is a component for fixing the sensor body and the frame to the bumper and is made of a synthetic resin or the like.

[0005] Patent Document 1: Japanese Patent Application Publication No. 2018-146564

[0006] As described in Patent Document 1, in such an ultrasonic sensor, there is a concern that false detection may occur due to vibration transmission between the ultrasonic sensor and the vehicle body component (i.e., bumper, etc.) to which it is installed. Therefore, it is required to avoid the above-mentioned false detection as much as possible by suppressing the vibration transmission between the ultrasonic sensor and the vehicle body component as much as possible. Summary of the invention

[0007] The present disclosure has been made in view of the above-mentioned circumstances, etc. Specifically, the present disclosure provides, for example, an ultrasonic sensor capable of suppressing as much as possible the transmission of vibrations to a vehicle body member to which it is mounted, and a vibration absorber provided on the ultrasonic sensor.

[0008] The vibration absorber is a component for mounting an ultrasonic sensor on a plate-shaped vehicle body component, wherein the ultrasonic sensor has a columnar ultrasonic microphone extending along an axial direction parallel to a central axis. The vibration absorber is provided on the ultrasonic sensor in a vehicle-mounted state where the ultrasonic sensor is mounted on the vehicle body component, so as to be sandwiched between a sensor mounting tool provided to surround the side of the ultrasonic microphone and the ultrasonic microphone.

[0009] According to one aspect of the present disclosure, a vibration absorber has:

[0010] a large diameter portion arranged to contact the ultrasonic microphone and the sensor mounting tool and to be sandwiched between the ultrasonic microphone and the sensor mounting tool; and

[0011] The small diameter portion is arranged adjacent to the large diameter portion in the circumferential direction surrounding the central axis, and the outer diameter centered on the central axis is formed smaller than that of the large diameter portion.

[0012] The pair of large diameter portions are arranged opposite to each other across the central axis.

[0013] The pair of small diameter portions are arranged opposite to each other across the central axis.

[0014] The vibration absorber is configured such that an arrangement direction of the pair of large diameter portions sandwiching the central axis and an arrangement direction of the pair of small diameter portions sandwiching the central axis are orthogonal to each other.

[0015] According to another aspect of the present disclosure, an ultrasonic sensor includes the vibration absorber, the sensor mounting tool, and a vibration-proof spacer.

[0016] The sensor mounting tool comprises a cylindrical portion and a flange portion. The cylindrical portion is provided to surround the ultrasonic microphone and is accommodated in a through hole formed in the vehicle body component in the vehicle-mounted state. The flange portion is provided to protrude radially extending radially from the center axis at one end of the cylindrical portion in the axial direction. The flange portion is formed to have an outer diameter larger than that of the through hole in a manner that it is opposed to a portion surrounding the through hole in the outer surface of the vehicle body component in the vehicle-mounted state. The vibration-proof insulator is formed of a synthetic resin-based elastic material and is provided to be clamped between the sensor mounting tool and the vehicle body component. Specifically, the vibration-proof insulator is provided to be clamped between the flange portion and the vehicle body component.

[0017] In addition, in each part of the application document, there is a case where each element is marked with a reference figure mark in brackets. In this case, the reference figure mark only represents an example of the correspondence between the element and the specific structure described in the embodiment described later. Therefore, the present disclosure is not limited in any way by the description of the reference figure mark. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1A It is a perspective view showing the appearance of a vehicle equipped with the ultrasonic sensor according to the embodiment.

[0019] Figure 1B It is a magnified representation Figure 1A A rear view of the area around the mounting holes in the front bumper is shown.

[0020] Figure 2A Indicates the vehicle status Figure 1A A top view of the ultrasonic sensor is shown.

[0021] Figure 2BIndicates the vehicle status Figure 1A Rear view of the ultrasonic sensor shown.

[0022] Figure 2C Indicates the vehicle status Figure 1A Right side view of the ultrasonic sensor shown.

[0023] Figure 2D Indicates the vehicle status Figure 1A Left side view of the ultrasonic sensor shown.

[0024] Figure 3A Yes means Figure 2A A top view of the schematic structure of the sensor body is shown.

[0025] Figure 3B yes Figure 3A Left side view of the sensor body shown.

[0026] Figure 4 Yes means Figure 3A A partial cross-sectional view showing the schematic structure of the sensor body.

[0027] Figure 5 yes Figure 4 Front view of microphone housing shown.

[0028] Fig. 6A It is a magnified representation Figure 2A A top view of the anti-vibration isolator is shown.

[0029] Figure 6B yes Figure 2A A front view of the anti-vibration isolator is shown.

[0030] Figure 7 It means that Figure 2A The schematic top view of the secondary assembly composed of the sensor body, vibration isolation spacer and frame is shown.

[0031] Fig. 8A It is a magnified representation Figure 7 A top view of the frame is shown.

[0032] Figure 8B yes Fig. 8A Front view of the frame shown.

[0033] Figure 8C yes Fig. 8A Right side view of the frame shown.

[0034] Fig. 9A This is a cross-sectional view showing a part of the frame of the first embodiment and its surrounding parts in an enlarged manner in a vehicle-mounted state.

[0035] Fig. 9BThis is a cross-sectional view showing a part of the frame of the first embodiment and its surrounding parts in an enlarged manner in a vehicle-mounted state.

[0036] Fig. 10A yes Figure 2A to Figure 2D Rear view of the retainer shown.

[0037] Fig. 10B yes Figure 2A to Figure 2D Right side view of the retainer shown.

[0038] Fig. 10C yes Figure 2A to Figure 2D A top view of the retainer is shown.

[0039] Fig. 10D yes Figure 2A to Figure 2D A front view of the retainer is shown.

[0040] Fig.11 This is a cross-sectional view showing a part of the cushioning member according to the second embodiment in an enlarged manner.

[0041] Fig.12 This is a cross-sectional view showing a part of a shock absorbing member according to a third embodiment in an enlarged manner.

[0042] Fig.13 This is a cross-sectional view showing, in an enlarged manner, a part of the frame of the fourth embodiment and its surrounding parts in a vehicle-mounted state.

[0043] Fig.14 This is a cross-sectional view showing a part of the frame of the fifth embodiment and its surrounding parts in an enlarged manner in a vehicle-mounted state. DETAILED DESCRIPTION

[0044] (Implementation Method)

[0045] The following describes the embodiments of the present disclosure based on the accompanying drawings. In addition, if various modified examples that can be applied to an embodiment are inserted in the middle of a series of descriptions related to the embodiment, there is a concern that the understanding of the embodiment may be hindered. Therefore, the modified examples are not inserted in the middle of a series of descriptions related to the embodiment, but are collectively described later.

[0046] (Vehicle-mounted structure)

[0047] If you refer to Figure 1A In the present embodiment, the ultrasonic sensor 1 has a structure as a vehicle-mounted clearance sonar to be mounted on a vehicle V. That is, the ultrasonic sensor 1 is configured to be able to detect objects existing around the vehicle V by being mounted on the vehicle V.

[0048] The vehicle V is a so-called four-wheeled vehicle, and has a box-shaped body V1. The body V1 has a body panel V2, a front bumper V3, and a rear bumper V4, which are plate-shaped body parts constituting an outer plate. The front bumper V3 is provided at the front end of the body V1. The rear bumper V4 is provided at the rear end of the body V1. In the present embodiment, the front bumper V3 and the rear bumper V4 are formed of metal plates.

[0049] The ultrasonic sensor 1 is configured to detect objects in front of and to the front side of the vehicle V by being mounted on the front bumper V3. Similarly, the ultrasonic sensor 1 is configured to detect objects in the rear of and to the rear side of the vehicle V by being mounted on the rear bumper V4. Hereinafter, the state in which the ultrasonic sensor 1 is mounted on the vehicle V by being mounted on the front bumper V3 and the rear bumper V4 provided on the vehicle body V1 is referred to as a "vehicle-mounted state".

[0050] Furthermore, the ultrasonic sensor 1 can be usually attached to or detached from the front bumper V3 after the front bumper V3 is removed from the vehicle body V1. Therefore, the "vehicle-mounted state" includes the "installed state" in which the ultrasonic sensor 1 is attached to the front bumper V3. The same is true for the attachment or detachment of the ultrasonic sensor 1 to the rear bumper V4.

[0051] In this embodiment, in the vehicle-mounted state, a plurality of (for example, four) ultrasonic sensors 1 are installed on the front bumper V3. The plurality of ultrasonic sensors 1 installed on the front bumper V3 are respectively arranged at different positions in the vehicle width direction. Similarly, a plurality of (for example, four) ultrasonic sensors 1 are also installed on the rear bumper V4. Through holes, i.e., mounting holes V5, for mounting the ultrasonic sensors 1 are provided on the front bumper V3 and the rear bumper V4.

[0052] In order to prevent the ultrasonic sensor 1 from being installed incorrectly, Figure 1B As shown, a bumper side snap-in portion V52 is provided in the mounting hole V5. "Incorrect installation" includes installing an ultrasonic sensor 1 with an incorrect product number that is different from the ultrasonic sensor that should be installed in the mounting hole V5 in a specific vehicle V. In addition, "incorrect installation" includes installing an ultrasonic sensor 1 with a correct product number in a mounting posture different from the original one. The mounting posture is a rotation posture centered on the pointing axis of the ultrasonic sensor 1 in the installed state. The so-called "pointing axis" is an imaginary straight line extending from the ultrasonic sensor 1 along the direction of sending and receiving ultrasound, which serves as a reference for the pointing angle. The "pointing axis" may also be called a pointing center axis or a detection axis.

[0053] The bumper side engaging portion V52 includes a through hole formed in a substantially circular shape, that is, a portion where the diameter of the mounting hole V5 changes, and is provided at a predetermined position in the circumferential direction of the mounting hole V5. The diameter of the mounting hole V5 is the distance from the center position CP of the mounting hole V5 to the inner edge V51. The center position CP is the position of the center point of the arc in the portion of the mounting hole V5 other than the bumper side engaging portion V52 that is in the shape of an arc when viewed from the front. Specifically, the center position CP is the distance between the inner edge V51 and the cylindrical inner surface of the mounting hole V5. Figure 2A The center position of the arc of the intersection line of the bumper outer surface V31 or the bumper back surface V32 described later is shown. Alternatively, the center position CP is the center position of the arc of the intersection line of the bumper outer surface V31 or the bumper back surface V32 described later. Alternatively, the center position CP is the center position of the arc of the bumper outer surface V31 or the bumper back surface V32 described later. Figure 2A The position on the XZ plane of the central axis CL described later is shown.

[0054] Specifically, in this embodiment, if Figure 1B As shown, the bumper side engaging portion V52 has a bumper side convex portion V53 and a pair of bumper side concave portions V54. The bumper side convex portion V53 is a convex portion protruding from the inner edge V51 of the mounting hole V5 toward the center position CP, and the front end portion in the protruding direction is formed into a rounded shape when viewed from the front. The bumper side concave portions V54 are portions that are formed into concave shapes relatively at both ends of the bumper side convex portion V53 in the circumferential direction by providing the bumper side convex portion V53, and are formed into a rounded shape when viewed from the front.

[0055] (First Embodiment)

[0056] Figure 2A to Figure 2D In the vehicle-mounted state, one ultrasonic sensor 1 among a plurality of ultrasonic sensors 1 mounted on the front bumper V3 is shown. Figure 2A The structure of the first embodiment will be described by taking one ultrasonic sensor 1 among the plurality of ultrasonic sensors 1 mounted on the front bumper V3 as an example.

[0057] For ease of explanation, as shown in the figure, a right-handed XYZ orthogonal coordinate system is set based on the direction of gravity in the vehicle-mounted state. In the right-handed XYZ coordinate system shown in the figure, the upper direction along the vertical top is set as the positive direction of the Z axis. The so-called vertical top is the direction opposite to the direction of gravity when the vehicle V is stably placed on a horizontal plane in a drivable state. The so-called upper direction is the same direction as the vertical top or the direction that forms a specified smaller acute angle α with the vertical top. α is, for example, less than 10 degrees. Therefore, depending on the shape of the front bumper V3, there is a situation where the positive direction of the Z axis is the same direction as the vertical top, or a direction that intersects with the vertical top. Similarly, with respect to the positive direction of the Y axis, there is also a situation where it is the same direction as the horizontal direction, or a direction that intersects with the horizontal direction.

[0058] If you refer to Figure 2A The front bumper V3 has a bumper outer surface V31 and a bumper back surface V32. The bumper outer surface V31 is the outer surface of the front bumper V3, and is provided as a bumper outer space SG that faces the space that becomes the outer side of the vehicle V when the vehicle is mounted. The bumper back surface V32 is the back surface of the bumper outer surface V31, and is provided as a bumper inner space SN that faces the space that becomes the inner side of the vehicle V when the vehicle is mounted. The mounting hole V5 is provided so as to penetrate the front bumper V3 in the thickness direction by opening in the bumper outer surface V31 and the bumper back surface V32. The mounting hole V5 is formed as a circular hole having a cylindrical space inside. That is, the mounting hole V5 has an inner edge V51 in the shape of a cylindrical inner surface.

[0059] The ultrasonic sensor 1 is configured to be able to transmit and receive ultrasonic waves. That is, the ultrasonic sensor 1 is configured to transmit a detection wave as an ultrasonic wave toward the bumper outer space SG along the central axis CL. In addition, the ultrasonic sensor 1 is configured to receive a reception wave including a reflection wave, which is a detection wave reflected by an object existing in the bumper outer space SG, and to generate and output a detection signal corresponding to the reception result of the reception wave.

[0060] In the right-hand XYZ coordinate system shown in the figure, the transmission direction of the detection wave parallel to the central axis CL constituting the directional axis of the ultrasonic sensor 1 is set to the positive direction of the Y axis. The positive direction of the Y axis parallel to the central axis CL is referred to as the "axial direction". In the following, there is a case where the end on the positive direction side of the Y axis of the two axial ends of the component extending in the axial direction is referred to as the "front end in the axial direction", and the end on the negative direction side of the Y axis is referred to as the "base end in the axial direction". In addition, in the following, the axial dimension of a certain component or part is simply referred to as the "axial dimension".

[0061] In addition, any direction perpendicular to the axial direction is referred to as an "in-plane direction". An "in-plane direction" is a direction parallel to the XZ plane. There is a case where the shape of a component within a plane perpendicular to the central axis CL, that is, the shape projected onto the XZ plane, is referred to as the "in-plane shape".

[0062] "In-plane direction" includes "radial direction" and "circumferential direction". "Radial direction" is a direction extending radially from the center axis CL. That is, "radial direction" is a direction orthogonal to the center axis CL and away from the center axis CL. Specifically, when a ray is drawn in an imaginary plane with the intersection of the imaginary plane orthogonal to the center axis CL and the center axis CL as the starting point, the "radial direction" is the direction in which the ray extends. In other words, the "radial direction" is the radius direction of an imaginary circle drawn in the imaginary plane with the intersection of the above-mentioned imaginary plane and the center axis CL as the center. "Circumferential direction" is the circumferential direction of the above-mentioned imaginary circle surrounding the center axis CL.

[0063] In the present embodiment, the ultrasonic sensor 1 is mounted on the vehicle V so that the center axis CL is substantially parallel to the thickness direction of the front bumper V3 in the vicinity of the mounting position when mounted on the vehicle. The so-called "mounting position" is the position where the ultrasonic sensor 1 is mounted on the front bumper V3, typically the center position CP of the mounting hole V5.

[0064] If you refer to Figure 2A to Figure 2D 3 , the sensor body 2 constituting the main body of the ultrasonic sensor 1 includes a sensor housing 3, an ultrasonic microphone 4, and a buffer member 5. The sensor body 2 is mounted on the front bumper V3 using a vibration isolation member 6, a frame 7, and a retainer 8. The specific structure of each part constituting the ultrasonic sensor 1 will be described below.

[0065] (Sensor housing)

[0066] Figure 3A and Figure 3B Indicates that from Figure 2A to Figure 2D The ultrasonic sensor 1 in the installation state shown is in a state after the retainer 8 is removed and the secondary assembly is taken out to the side of the bumper outer space SG, and the frame 7 is removed from the secondary assembly. The secondary assembly is a primary assembly formed by assembling the ultrasonic microphone 4 and the buffer component 5 to the sensor housing 3, that is, an assembly after the vibration isolation 6 and the frame 7 are further assembled to the sensor body 2. Hereinafter, there is a case where the state in which the secondary assembly is formed is referred to as an "assembled state". The "installed state" and the "vehicle-mounted state" are also equivalent to the "assembled state".

[0067] If you refer to Figure 3A and Figure 3B The sensor housing 3 constituting the housing of the ultrasonic sensor 1, namely the sensor body 2, has a box-shaped portion 31, a connector portion 32, and a microphone support portion 33. The sensor housing 3 is integrally formed of a hard synthetic resin such as polybutylene terephthalate, ABS resin, polypropylene, polycarbonate, or polystyrene.

[0068] The box-shaped portion 31 is formed into a box-shaped outer shape having a long side direction in the X-axis direction and being thin in the Y-axis direction in the installed state. Figure 3A Partial cross-sectional view of Figure 4 As shown, a circuit board 34 is housed inside the box-shaped portion 31 . The circuit board 34 is electrically connected to the ultrasonic microphone 4 via a connection wiring 35 .

[0069] The connector portion 32 extends from one end portion (i.e., Figure 2A and Figure 3AThe connector portion 32 is provided to extend substantially horizontally and obliquely rearward (left end portion in FIG. 1 ). That is, in the installed state, the connector portion 32 is provided to extend in a direction away from the front bumper V3. The connector portion 32 has a structure as a socket connector, and the socket connector can be detached from a plug connector (not shown) provided at the end of a wiring harness for electrical connection with an external device such as an ECU. ECU is an abbreviation for Electronic Control Unit.

[0070] The microphone support portion 33 extends from the other end portion (i.e., Figure 2A and Figure 3A The microphone support portion 33 has a cylindrical shape surrounding the central axis CL. In the present embodiment, the microphone support portion 33 is formed into a cylindrical shape with the central axis CL as the axis center.

[0071] like Figure 3A , Figure 3B as well as Figure 4 As shown, a buffer locking protrusion 36 and a frame locking protrusion 37 are provided at the front end portion in the axial direction of the microphone support portion 33. The buffer locking protrusion 36 is a protrusion protruding from the inner wall surface of the cylindrical inner surface surrounding the central axis CL in the microphone support portion 33 toward the central axis CL, and is provided to extend in the circumferential direction. The frame locking protrusion 37 is a small protrusion protruding in the radial direction from the outer wall surface of the cylindrical surface surrounding the central axis CL in the microphone support portion 33, and a plurality of them are arranged in the circumferential direction.

[0072] (Ultrasonic Microphone)

[0073] If you refer to Figure 4 and Figure 5 The ultrasonic microphone 4 has a columnar outer shape extending in the axial direction. Specifically, in the present embodiment, the ultrasonic microphone 4 is formed in a substantially cylindrical shape with the central axis CL as the axis center.

[0074] The ultrasonic microphone 4 includes an ultrasonic element 41 and a microphone case 42 . The ultrasonic element 41 is a so-called electromechanical transducer element, and is formed of a thin-film piezoelectric element, etc. The ultrasonic element 41 is accommodated inside the microphone case 42 .

[0075] The microphone case 42 constituting the housing of the ultrasonic microphone 4 is formed of a metal material such as aluminum into a bottomed cylindrical shape. Specifically, the microphone case 42 includes a diaphragm 43 and a side plate portion 44 .

[0076] The diaphragm 43 is formed into a thin plate having a thickness direction in the axial direction. The diaphragm 43 is provided to close the front end portion in the axial direction of the side plate portion 44. The outer surface of the diaphragm 43 facing the bumper outer space SG in the installed state or the vehicle-mounted state is formed into a smooth plane. The ultrasonic element 41 is fixed to the inner surface of the back side of the outer surface of the diaphragm 43.

[0077] like Figure 5 As shown, the diaphragm 43 is formed to have an in-plane shape having a long side direction and a short side direction substantially orthogonal to each other. Specifically, the diaphragm 43 has an in-plane shape of an oblong or elliptical shape having a long side direction along the vertical direction when mounted on the vehicle.

[0078] The side plate 44 is a substantially cylindrical portion of the microphone case 42 and extends in the axial direction. The side surface 44a constituting the side plate 44, that is, the outer wall surface of the ultrasonic microphone 4, is formed in a cylindrical surface shape with the central axis CL as the axis center.

[0079] The side plate portion 44 has a thin-walled portion 44b and a thick-walled portion 44c corresponding to the in-plane shape of the diaphragm 43. The thin-walled portion 44b is arranged at positions corresponding to both ends in the long side direction of the diaphragm 43. A pair of thin-walled portions 44b are arranged in a substantially vertical up-down direction in the vehicle-mounted state, and are symmetrically arranged across the central axis CL. On the other hand, the thick-walled portion 44c is arranged at positions corresponding to both ends in the short side direction of the diaphragm 43. A pair of thick-walled portions 44c are arranged in a substantially horizontal direction in the vehicle-mounted state, and are symmetrically arranged across the central axis CL.

[0080] A pair of engagement grooves 45 are formed in the side plate portion 44. The engagement grooves 45 are quadrangular grooves extending parallel to the Z-axis direction in the figure and provided in the thick wall portion 44c. The pair of engagement grooves 45 are symmetrically arranged with the central axis CL interposed therebetween.

[0081] (Buffering parts)

[0082] The following are mainly used Figure 3A , Figure 3B , Figure 4 as well as Figure 5 , the details of the structure of the buffer member 5 constituting the vibration absorber of the present disclosure will be described.

[0083] The buffer member 5 is a member for mounting the ultrasonic sensor 1 on the front bumper V3 as a plate-shaped vehicle body member, and is seamlessly integrally formed of a synthetic resin elastic material such as silicone rubber. In the present embodiment, the buffer member 5 is a member constituting the sensor body 2 together with the ultrasonic microphone 4, and is pre-set on the sensor body 2 as a primary assembly.

[0084] The buffer member 5 is formed into a cylindrical shape surrounding the central axis CL. Specifically, in the present embodiment, the buffer member 5 has a substantially cylindrical shape with the central axis CL as the axis center, and the substantially cylindrical shape has an outer diameter substantially the same as the outer diameter of the microphone support portion 33 and an inner diameter substantially the same as the outer diameter of the side plate portion 44. In addition, the buffer member 5 is formed to have an axial dimension larger than that of the ultrasonic microphone 4.

[0085] The buffer member 5 is fixed to the microphone support portion 33 via a supported portion 51 as a base end portion in the axial direction. Specifically, a radially open locking groove 52 is provided in the supported portion 51. The locking groove 52 is a groove of a shape that engages with the buffer locking protrusion 36 provided on the microphone support portion 33, and is provided to extend in the circumferential direction.

[0086] The microphone housing portion 53, which is a portion of the buffer member 5 that is closer to the front end side in the axial direction than the supported portion 51, is configured to house the ultrasonic microphone 4 across almost the entire axial direction. That is, the microphone housing portion 53 has a columnar internal space corresponding to the outer shape of the ultrasonic microphone 4 so as to cover the side surface 44a of the ultrasonic microphone 4.

[0087] A pair of engagement protrusions 54 are provided on the microphone housing portion 53. The pair of engagement protrusions 54 are arranged opposite to each other across the central axis CL. The engagement protrusions 54 are rectangular protrusions in a cross-sectional view, which are shaped to fit into the engagement groove 45 as a square groove and protrude toward the central axis CL, and are extended in the Z-axis direction in the figure.

[0088] In this way, the buffer member 5 is provided so as to be fixed to the sensor housing 3 via the base end side in the axial direction and to elastically support the ultrasonic microphone 4 at the front end side in the axial direction. That is, the ultrasonic sensor 1 in the present embodiment is configured so as to suppress the vibration transmission between the sensor housing 3 and the ultrasonic microphone 4 by elastically supporting the ultrasonic microphone 4 on the sensor housing 3 via the buffer member 5.

[0089] In addition, the buffer member 5 is provided on the ultrasonic sensor 1 in a vehicle-mounted state so as to be sandwiched between the frame 7 provided to surround the side surface 44a of the ultrasonic microphone 4 and the ultrasonic microphone 4. That is, the buffer member 5 is configured to suppress the transmission of vibration between the ultrasonic microphone 4 and the front bumper V3 by being sandwiched between the ultrasonic microphone 4 and the front bumper V3.

[0090] The microphone housing portion 53 in the buffer member 5 includes a front end portion 55, a first cylindrical portion 56, and a second cylindrical portion 57. The front end portion 55, the first cylindrical portion 56, and the second cylindrical portion 57 are arranged in this order in the axial direction.

[0091] The front end portion 55 is the most front end portion of the buffer member 5 in the axial direction and is formed in a tapered shape having a partially conical outer wall surface whose outer diameter decreases toward the front end in the axial direction and a cylindrical inner surface inner wall surface.

[0092] The first cylindrical portion 56 is a portion adjacent to the front end portion 55 in the axial direction, and is provided on the front end side in the axial direction of the buffer member 5. The first cylindrical portion 56 is configured to contact the ultrasonic microphone 4 and the frame 7, and is clamped between the ultrasonic microphone 4 and the frame 7. That is, the first cylindrical portion 56 has a maximum thickness that is almost the same as the size of the gap between the side surface 44a of the ultrasonic microphone 4 and the frame 7 in the assembled state. Specifically, in the present embodiment, the first cylindrical portion 56 is formed into a cylindrical shape with a constant thickness, that is, a radial dimension. In other words, the first cylindrical portion 56 is provided to abut against the ultrasonic microphone 4 and the frame 7 throughout the entire circumference.

[0093] The second cylindrical portion 57 is provided adjacent to the first cylindrical portion 56 on the base end side in the axial direction. The second cylindrical portion 57 has a pair of recessed portions 57a opened in the radial direction. The pair of recessed portions 57a are provided symmetrically with respect to the central axis CL.

[0094] That is, the second cylindrical portion 57 is provided with a large diameter portion 58 and a small diameter portion 59. The large diameter portion 58 is provided so as to be in contact with the ultrasonic microphone 4 and the frame 7 and to be sandwiched between the ultrasonic microphone 4 and the frame 7. Specifically, the large diameter portion 58 has a partial cylindrical shape having a maximum thickness that is substantially the same as the size of the gap between the side surface 44a of the ultrasonic microphone 4 and the frame 7 in the assembled state. In addition, the large diameter portion 58 is formed so that the diameter of the inner wall surface and the outer wall surface centered on the central axis CL are substantially the same as those of the first cylindrical portion 56.

[0095] The small diameter portion 59 is arranged adjacent to the large diameter portion 58 in the circumferential direction, and the outer diameter centered on the central axis CL is formed to be smaller than that of the large diameter portion 58. The small diameter portion 59 is formed to be thinner than the large diameter portion 58 by providing the recess 57a in the second cylindrical portion 57, and is arranged at a position corresponding to the recess 57a in the circumferential direction. That is, the small diameter portion 59 is formed so that the gap with the frame 7 is larger than the gap between the large diameter portion 58 and the frame 7. The diameter of the inner wall surface of the small diameter portion 59 centered on the central axis CL is substantially consistent with the first cylindrical portion 56.

[0096] The pair of large diameter portions 58 are arranged opposite to each other across the central axis CL. In addition, the pair of small diameter portions 59 are arranged opposite to each other across the central axis CL. That is, one large diameter portion 58 of the pair of large diameter portions 58, one small diameter portion 59 of the pair of small diameter portions 59, the other large diameter portion 58 of the pair of large diameter portions 58, and the other small diameter portion 59 of the pair of small diameter portions 59 are arranged adjacent to each other in sequence in the circumferential direction. Furthermore, the buffer member 5 is configured so that the arrangement direction of the pair of large diameter portions 58 across the central axis CL and the arrangement direction of the pair of small diameter portions 59 across the central axis CL are orthogonal to each other.

[0097] In this embodiment, the large diameter portion 58 is formed to have a circumferential length shorter than the circumferential length of the small diameter portion 59. Figure 3A , Figure 3B as well as Figure 5 As can be seen from the figure in FIG, the large diameter portion 58 is provided at positions corresponding to both ends in the short-side direction of the diaphragm 43. On the other hand, the small diameter portion 59 is provided at positions corresponding to both ends in the long-side direction of the diaphragm 43.

[0098] (anti-vibration isolator)

[0099] If you refer to Fig. 6A and Figure 6B The vibration isolator 6 is a thin plate-shaped and annular member having a thickness direction in the axial direction, and is formed of a synthetic resin elastic material such as silicone rubber. Specifically, in this embodiment, the vibration isolator 6 has a shape in which a circular through hole, namely, a spacer through hole 61, is provided through the center of the disc-shaped member.

[0100] like Figure 2A and Figure 2C As shown, the vibration-proof insulator 6 is provided between the flange portion 71 described later in the frame 7 and the front bumper V3 in the vehicle-mounted state to suppress the transmission of vibration between the frame 7 and the front bumper V3. That is, the vibration-proof insulator 6 is sandwiched between the frame 7 and the front bumper V3 in the mounted state, and is clamped between the back surface 71a of the flange portion 71 which is opposite to the front bumper V3 and the bumper outer surface V31.

[0101] (frame)

[0102] Figure 7 It represents the above-mentioned secondary assembly. Figure 8A to Figure 8C The schematic structure of the frame 7 is shown. Fig. 9A and Fig. 9B It is a cross-sectional view showing an enlarged view of the periphery of the flange portion 71 of the bezel 7 in the mounted state or the vehicle-mounted state. Fig. 9A It is a cross-sectional view of a cross section including the central axis CL and parallel to the XY plane. Fig. 9BIt is a cross-sectional view of a cross section which includes the central axis CL and is parallel to the YZ plane. Hereinafter, the structure of the bezel 7 as the sensor mounting tool in the present disclosure will be described.

[0103] The bezel 7 is a member for attaching the ultrasonic sensor 1 to the front bumper V3 which is a plate-shaped vehicle body member, and is integrally formed of a hard synthetic resin.

[0104] A flange portion 71 is provided at the front end portion of the frame 7 in the axial direction. The flange portion 71 is an annular portion having a thickness direction in the axial direction and is provided to protrude in the radial direction. The flange portion 71 is formed to have an outer diameter larger than the inner diameter of the mounting hole V5. Figure 2A As shown in FIGS. 1 and 10 , the flange portion 71 is provided so as to face a portion around the mounting hole V5 in the bumper outer surface V31 via the vibration isolation spacer 6 in the mounted state.

[0105] A spacer receiving groove 71b for receiving the vibration-proof spacer 6 is provided to be opened in the radial direction at a position adjacent to the flange portion 71 and closer to the base end side than the flange portion 71 in the axial direction. The spacer receiving groove 71b is formed to have a width corresponding to the thickness of the vibration-proof spacer 6, i.e., an axial dimension, and a depth corresponding to the diameter of the spacer through hole 61 in the vibration-proof spacer 6, i.e., a radial dimension. The spacer receiving groove 71b is provided to extend across the entire frame 7 in the circumferential direction.

[0106] The spacer receiving groove 71b is provided between the flange 71 and the cylindrical portion 72. That is, the flange 71 protrudes radially at one end, i.e., the front end, of the cylindrical portion 72 extending in the axial direction. The flange 71 and the cylindrical portion 72 are seamlessly integrally formed of the same material.

[0107] The cylindrical portion 72 is provided to surround the ultrasonic microphone 4 and the buffer member 5 and to be accommodated in the mounting hole V5 in the assembled state and the mounted state. The cylindrical portion 72 has an outer diameter slightly smaller than the inner diameter of the mounting hole V5 and an inner diameter slightly larger than the outer diameters of the microphone support portion 33 and the buffer member 5. The main body 73, which is a cylindrical portion including the central portion in the axial direction of the cylindrical portion 72, is extended along the central axis CL.

[0108] The main body 73 is provided with a sensor locking piece 74. The sensor locking piece 74 is a cantilever beam-shaped tongue piece having a thickness direction in the radial direction, and is extended from the front end portion in the axial direction toward the base end portion of the main body 73. That is, the sensor locking piece 74 is formed with the front end portion in the axial direction as a fixed end and the base end portion in the axial direction as a free end, and can be elastically deformed in a manner that the free end moves in the radial direction.

[0109] A locking hole 74a is provided on the free end side of the sensor locking piece 74, which penetrates the sensor locking piece 74 in the thickness direction. The locking hole 74a is formed so as to be detachably engaged with the frame locking protrusion 37 provided on the microphone support part 33 in the assembled state. In the main body 73, the same number of sensor locking pieces 74 as the frame locking protrusion 37 are provided so as to be arranged in the circumferential direction.

[0110] At the base end portion in the axial direction of the main body 73, the base end side protruding portion 75 is integrally connected to the main body 73 and protrudes in the radial direction. In the present embodiment, the main body 73 and the base end side protruding portion 75 are seamlessly integrally formed of the same material. The end surface of the base end side protruding portion 75 in the axial direction, that is, the retainer contact surface 75a is formed into a smooth plane having a normal direction parallel to the central axis CL.

[0111] A retainer insertion groove 75b is formed on the front end side of the retainer abutment surface 75a in the axial direction and is open in the radial direction. In the present embodiment, a pair of retainer insertion grooves 75b are symmetrically arranged across the central axis CL. The retainer insertion groove 75b is a space for the retainer 8 to be inserted when the ultrasonic sensor 1 is mounted on the front bumper V3, and is formed in the shape of a square groove extending in the Z-axis direction in the figure. That is, the protruding portion 75 on the base end side is configured to clamp the retainer 8 inserted in the retainer insertion groove 75b between the bumper back surface V32 in the mounted state.

[0112] like Figure 8C As shown, the cylindrical portion 72 has a temporary assembly piece 76. The temporary assembly piece 76 is a tongue piece in a cantilever beam shape having a thickness direction in the radial direction, and is axially extended from the protruding portion 75 on the base end side toward the flange portion 71. That is, the temporary assembly piece 76 is formed so that the base end portion in the axial direction is a fixed end and the front end portion in the axial direction is a free end, and can be elastically deformed in a manner that the free end moves in the radial direction.

[0113] A temporary assembly protrusion 76a protruding radially is provided at the free end of the temporary assembly piece 76, i.e., the front end in the axial direction. The temporary assembly protrusion 76a is configured to be able to hold the secondary assembly in a temporary assembly state. The temporary assembly state is a state in which the secondary assembly is temporarily held by the front bumper V3 in a predetermined temporary assembly posture by inserting the frame 7 in the secondary assembly into the mounting hole V5. The temporary assembly posture is such that the vibration isolation member 6 is in contact with or close to and opposite to the bumper outer surface V31 in the front bumper V3, and the connector portion 32 is as shown in FIG. Figure 2B As shown, the secondary assembly is in a posture extending in the negative direction of the X axis in the figure when viewed from the back. The provisional assembly state corresponds to a state where the holder 8 is removed from the ultrasonic sensor 1 in the vehicle-mounted state.

[0114] Specifically, the temporary assembly protrusion 76a has a wedge-shaped outer shape, and the wedge-shaped outer shape has an inclined surface 76b and a flange facing surface 76c. The inclined surface 76b is a surface of the temporary assembly protrusion 76a exposed in the radial direction, and is provided to be away from the central axis CL as it goes toward the front end side in the axial direction. The flange facing surface 76c is an end surface of the temporary assembly protrusion 76a, and is provided to face the back surface 71a of the flange portion 71.

[0115] At the front end portion in the axial direction of the main body portion 73, the front end side protruding portion 77 is integrally connected to the main body portion 73 and protrudes in the radial direction. The front end side protruding portion 77 is the portion on the front end side in the axial direction of the cylindrical portion 72 and extends in the circumferential direction. In this embodiment, the main body portion 73 and the front end side protruding portion 77 are seamlessly integrally formed of the same material.

[0116] The front end side protruding setting part 77 is arranged between the spacer receiving groove 71b and the retainer insertion groove 75b in the axial direction. That is, the front end side protruding setting part 77 is arranged to be adjacent to the spacer receiving groove 71b and the retainer insertion groove 75b in the axial direction. Therefore, the spacer receiving groove 71b is formed to include a gap between the flange part 71 and the front end side protruding setting part 77. In addition, the retainer insertion groove 75b is formed by the space between the base end side protruding setting part 75 and the front end side protruding setting part 77.

[0117] The front end side protruding portion 77 has a frame side engaging portion 77a. The frame side engaging portion 77a is formed to Figure 1B The frame side engagement portion 77a has a shape corresponding to the shape of the bumper side engagement portion V52.

[0118] Specifically, in the present embodiment, the frame side engaging portion 77a has a frame side recessed portion 77b and a pair of frame side convex portions 77c. The frame side recessed portion 77b has a shape corresponding to the bumper side convex portion V53. That is, the frame side recessed portion 77b is a recessed portion opening toward the radial direction, and is provided at a predetermined position in the circumferential direction of the front end side protruding portion 77 extending in the circumferential direction. The frame side convex portion 77c has a shape corresponding to the bumper side recessed portion V54. That is, the frame side convex portion 77c is a portion that is relatively formed into a convex shape at both ends of the frame side recessed portion 77b in the circumferential direction by providing the frame side recessed portion 77b.

[0119] like Fig. 9A and Fig. 9B As shown in FIG. 1 , the front end protruding portion 77 has a root portion 77d, an intermediate portion 77e, and a terminal portion 77f. The root portion 77d, the intermediate portion 77e, and the terminal portion 77f are arranged in this order in the radial direction.

[0120] The root portion 77d is the portion of the front end protruding portion 77 that is closest to the main body 73, and is formed to have an axial dimension that is larger than the thickness of the front bumper V3. The intermediate portion 77e is the portion between the root portion 77d and the terminal portion 77f in the radial direction, and is formed to have an axial dimension that is substantially the same as that of the root portion 77d. The terminal portion 77f is the portion of the front end protruding portion 77 that is farthest from the main body 73, and is formed to have a tapered shape whose axial dimension decreases as it moves toward the radial direction.

[0121] The through-hole opposing portion 78 in the frame 7 is a portion of the cylindrical portion 72, and is a portion that is close to and opposite to the inner edge V51 in the radial direction so as to be in contact with the inner edge V51 of the mounting hole V5 in the mounted state. Specifically, in the present embodiment, the through-hole opposing portion 78 is the front end side protruding portion 77. More specifically, the through-hole opposing portion 78 is a surface of the terminal portion 77f of the front end side protruding portion 77 in the radial direction that is close to and opposite to the inner edge V51.

[0122] (Retainer)

[0123] like Figure 2A to Figure 2D As shown, the retainer 8 as the sensor fixture of the present disclosure is configured to fix the ultrasonic sensor 1 to the front bumper V3 by assembling to a secondary assembly in a temporary assembly state inserted through the mounting hole V5. Specifically, the retainer 8 is inserted between the cylindrical portion 72 and the front bumper V3 in a state where the cylindrical portion 72 is inserted through the mounting hole V5, and is clamped between the cylindrical portion 72 and the front bumper V3 in a vehicle-mounted state. The retainer 8 is integrally formed of a hard synthetic resin.

[0124] FIG. 10A to FIG. 10D 8 shows a schematic structure of the retainer 8. Fig. 10A As shown in FIG. 1 , the retainer 8 is formed into a substantially U-shaped shape when viewed from the front, with the opening 81 opening in the positive direction of the Z axis. Specifically, the retainer body 82 constituting the main body of the retainer 8 has a connecting portion 83 extending in the X-axis direction in the figure and a pair of extending portions 84 extending from both ends of the connecting portion 83 in the positive direction of the Z axis in the figure.

[0125] That is, the connecting portion 83 is configured to connect one end of a pair of extended portions 84 to each other. The pair of extended portions 84 are configured to extend in a direction intersecting the central axis CL and to be opposite to each other across the central axis CL. Moreover, the retainer 8 is formed into a roughly U-shaped shape when viewed from the front by the connecting portion 83 and the pair of extended portions 84. The pair of extended portions 84 are configured to accommodate the cylindrical portion 72 in the frame 7 in the inner space formed between them and opened in the opening portion 81, and to clamp the cylindrical portion 72. In addition, the retainer 8 is configured so that the arrangement direction of the pair of extended portions 84 across the central axis CL is orthogonal to the arrangement direction of the pair of small diameter portions 59 across the central axis CL.

[0126] like Fig. 10B As shown, when viewed from the side, the retainer body 82 is formed into a substantially J-shape by the connecting portion 83 and a pair of extended portions 84. That is, the connecting portion 83 is formed into a plate shape having a thickness direction in the Z-axis direction in the figure. The extended portion 84 is formed into a plate shape having a thickness direction in the axial direction.

[0127] The extended portion 84 is reinforced by a rib-shaped reinforcement portion 85 protruding in the axial direction. Specifically, the reinforcement portion 85 includes a first rib 85a and a second rib 85b. The first rib 85a is provided at a middle position in the width direction of the extended portion 84, i.e., the X-axis direction in the figure, and extends along the extended direction of the extended portion 84, i.e., the Z-axis direction in the figure. The second rib 85b extends from the first rib 85a toward the outside of the extended portion 84 in the width direction.

[0128] The extended portion 84 has a frame abutment portion 86. Fig. 10A As shown, the frame contact portion 86 is a portion located inside the first rib 85 a in the width direction of the extending portion 84 , and is provided to protrude toward the inner space opened in the opening portion 81 .

[0129] The frame contact portion 86 has a frame contact surface 87. The frame contact surface 87 is a surface that contacts the retainer contact surface 75a of the frame 7 when in the mounted state, and is formed into a smooth plane having a normal direction parallel to the central axis CL in the mounted state.

[0130] like FIG. 10B to FIG. 10D As shown, the retainer 8 has a cantilever beam-shaped leaf spring portion, i.e., an elastic portion 88, extending from the retainer body 82. The elastic portion 88 is extended from the substantially central portion in the long side direction of the extension portion 84 in a direction inclined relative to the positive direction of the Y axis. Specifically, in the present embodiment, in each of the pair of extension portions 84, a pair of elastic portions 88 is provided in a gull-wing shape. The elastic portion 88 is configured to abut against the bumper back surface V32 and elastically deform when the retainer 8 is installed between the retainer abutting surface 75a in the frame 7 and the bumper back surface V32.

[0131] (Effect)

[0132] Hereinafter, the installation method and installation state of the ultrasonic sensor 1 relative to the front bumper V3 will be described with reference to the drawings together with the effects of the structure of the present embodiment. In addition, in order to simplify the description, the following installation method or installation process will be described using the right-handed XYZ orthogonal coordinate system based on the vehicle-mounted state as shown in the figure. As described above, the ultrasonic sensor 1 can usually be removed from the front bumper V3 and the rear bumper V4 after the front bumper V3 and the rear bumper V4 are removed from the vehicle body V1. Therefore, in the actual installation method or installation process, there may be a situation where the positive direction of the Z axis is different from the upward direction.

[0133] First, form Figure 3A , Figure 3B as well as Figure 4 The sensor body 2 shown. In addition, Fig. 6A The anti-vibration isolator 6 shown in the figure is installed on Fig. 8A Then, the ultrasonic microphone 4 and the buffer member 5 in the sensor body 2 are inserted into the frame 7 to which the vibration isolation spacer 6 is attached.

[0134] Then, the frame 7 is attached to the sensor body 2 by engaging the locking hole 74a provided in the sensor locking piece 74 of the cylindrical portion 72 with the frame locking protrusion 37 provided on the microphone support portion 33. In this way, by assembling the frame 7 with the vibration isolation member 6 installed to the sensor body 2, a sensor body 2 is formed. Figure 7 In this secondary assembly, the buffer member 5 surrounds the ultrasonic microphone 4 and is housed in the cylindrical portion 72 of the frame 7 .

[0135] Figure 7 The secondary assembly shown is inserted into the mounting hole V5 from the bumper outer space SG side with the connector portion 32 as the front end. When the cylindrical portion 72 in the frame 7 is inserted into the mounting hole V5, the inclined surface 76b in the temporary assembly protrusion 76a abuts against the inner edge V51, and the temporary assembly piece 76 is elastically deformed in the direction of the inner side, that is, the center axis CL, at its free end. Then, when the temporary assembly protrusion 76a passes through the mounting hole V5, the elastic deformation of the temporary assembly piece 76 is restored.

[0136] Then, the frame 7 is held on the front bumper V3 by using the flange portion 71 and the flange facing surface 76c in the temporary assembly protrusion 76a, and the secondary assembly body is in a temporary assembly state. In addition, the retainer 8 is in a disassembly posture on the side of the bumper inner space SN. The disassembly posture is a posture in which the opening portion 81 opens toward the positive direction of the Z axis in the figure, and the elastic portion 88 faces the bumper back surface V32.

[0137] The frame 7 in the provisionally assembled secondary assembly is inserted into the opening 81 of the holder 8 in the disassembly posture. Then, the extension portion 84 of the holder 8 is slid in the positive direction of the Z axis and inserted into the holder insertion groove 75b of the frame 7 in the secondary assembly.

[0138] If the retainer 8 is pressed in the positive direction of the Z axis in the figure to the extent that the frame 7 and the connecting portion 83 in the retainer 8 are closest, the frame contact surface 87 stably contacts the retainer contact surface 75a. In this state, the retainer 8 is clamped between the protruding portion 75 on the base end side of the frame 7 and the bumper back surface V32 due to the elastic restoring force of the elastic portion 88. In this way, by installing the retainer 8 to the secondary assembly in the temporary assembly state, as shown in FIG. Figure 2A to Figure 2D As shown, the ultrasonic sensor 1 is installed in the front bumper V3 or in the vehicle-mounted state.

[0139] In the installation state or vehicle state, such as Fig. 9A and Fig. 9B As shown, a buffer member 5, a vibration-proof spacer 6, and a frame 7 are sandwiched between the ultrasonic microphone 4 and the front bumper V3. Specifically, the buffer member 5 is sandwiched between the ultrasonic microphone 4 and the frame 7. In addition, the vibration-proof spacer 6 is sandwiched between the flange portion 71 in the frame 7 and the front bumper V3.

[0140] Two transmission paths can be assumed for the vibration transmission between the ultrasonic microphone 4 and the front bumper V3 through the frame 7. The first transmission path is the transmission path between the flange portion 71 and the front bumper V3. Regarding the first transmission path, the vibration transmission can be well suppressed by sandwiching the vibration-proof spacer 6 formed of a synthetic resin elastic material.

[0141] On the other hand, the second transmission path is a transmission path between the front end portion of the cylindrical portion 72 in the axial direction, that is, the front end side protruding setting portion 77 and the front bumper V3. Regarding this second transmission path, no vibration transmission suppression component such as the vibration isolation 6 is interposed. In particular, when the front bumper V3 is formed of a metal plate with high vibration transmission, there is a concern that false detection due to vibration transmission may occur.

[0142] In addition, in order to suppress the reception of unnecessary road surface reflections, the directional characteristics of the ultrasonic sensor 1 may be adjusted. Specifically, in this case, the directional angle in the vertical direction is made smaller than the directional angle in the horizontal direction. In order to adjust the directional characteristics, Figure 5 As shown, the diaphragm 43 is formed to have an in-plane shape having a long side direction and a short side direction that are orthogonal to each other. Specifically, the diaphragm 43 is formed to have an oblong or elliptical shape having a long side direction along the vertical up-and-down direction when mounted on the vehicle.

[0143] Thus, the side plate portion 44 in the microphone housing 42 has a structure having a thin-walled portion 44b and a thick-walled portion 44c. The thin-walled portion 44b is provided at positions corresponding to both ends in the long-side direction of the diaphragm 43. On the other hand, the thick-walled portion 44c is provided at positions corresponding to both ends in the short-side direction of the diaphragm 43. The long-side direction of the diaphragm 43 is a direction along the vertical up-and-down direction. The short-side direction of the diaphragm 43 orthogonal to the long-side direction of the diaphragm 43 is a horizontal direction.

[0144] The thin portion 44b vibrates more than the thick portion 44c. Therefore, there is a concern that vibration may be transmitted to the front bumper V3 at locations corresponding to the thin portion 44b, ie, around the upper and lower ends of the microphone case 42 when mounted on the vehicle.

[0145] Therefore, in this embodiment, the buffer member 5 provided between the ultrasonic microphone 4 and the frame 7 has the following structure. Specifically, the buffer member 5 has a large diameter portion 58 that contacts the ultrasonic microphone 4 and the frame 7 and is sandwiched between the ultrasonic microphone 4 and the frame 7, and a small diameter portion 59 that is adjacent to the large diameter portion 58 in the circumferential direction and has an outer diameter smaller than the large diameter portion 58. That is, Fig. 9A and Fig. 9B As shown, the small diameter portion 59 is formed so that the gap between the small diameter portion 59 and the cylindrical portion 72 is larger than the gap between the large diameter portion 58 and the cylindrical portion 72 .

[0146] The pair of large diameter portions 58 are arranged opposite to each other across the central axis CL. Similarly, the pair of small diameter portions 59 are arranged opposite to each other across the central axis CL. In addition, one large diameter portion 58 of the pair of large diameter portions 58, one small diameter portion 59 of the pair of small diameter portions 59, the other large diameter portion 58 of the pair of large diameter portions 58, and the other small diameter portion 59 of the pair of small diameter portions 59 are arranged adjacent to each other in sequence in the circumferential direction. Moreover, the buffer member 5 is configured so that the arrangement direction of the pair of large diameter portions 58 across the central axis CL and the arrangement direction of the pair of small diameter portions 59 across the central axis CL are orthogonal to each other.

[0147] According to this structure, the small diameter portion 59 forming the gap with the cylindrical portion 72 can be arranged at the positions corresponding to the two ends in the longitudinal direction of the diaphragm 43, that is, the thin wall portion 44b with large vibration. As a result, the vibration transmission between the ultrasonic microphone 4 and the frame 7 can be well suppressed. Therefore, according to this structure, the vibration transmission between the ultrasonic sensor 1 and the front bumper V3 as a vehicle body component, which is the object to be installed, can be suppressed as much as possible.

[0148] In addition, according to this structure, the large diameter portion 58 that contacts the cylindrical portion 72 can be set at the positions corresponding to the two ends in the short side direction of the diaphragm 43, that is, the thick wall portion 44c with less vibration. Therefore, the assembled state of the secondary assembly can be reliably maintained by the contact between the thick wall portion 44c with less vibration, the large diameter portion 58 and the cylindrical portion 72, and the vibration transmission can be well suppressed by the gap between the small diameter portion 59 corresponding to the thin wall portion 44b with greater vibration and the cylindrical portion 72.

[0149] In the present embodiment, large diameter portion 58 is formed to have a circumferential length shorter than that of small diameter portion 59. Therefore, the assembled state of the secondary assembly can be reliably maintained, and vibration transmission between ultrasonic microphone 4 and bezel 7 can be further well suppressed.

[0150] Furthermore, in the present embodiment, the arrangement direction of the pair of extension portions 84 of the cylindrical portion 72 in the clamping frame 7 is orthogonal to the arrangement direction of the pair of small diameter portions 59 across the central axis CL. That is, the direction in which the secondary assembly is clamped by the pair of extension portions 84 is orthogonal to the direction in which the thin-walled portion 44b with larger vibration is arranged across the central axis CL. On the other hand, the direction in which the secondary assembly is clamped by the pair of extension portions 84 is consistent with the direction in which the thick-walled portion 44c with smaller vibration is arranged across the central axis CL.

[0151] Therefore, in the direction in which the thin-walled portion 44b having a larger vibration is arranged across the central axis CL, a gap is formed between the buffer member 5 and the frame 7 by providing the small-diameter portion 59, and the frame 7 is not clamped by the pair of extended portions 84. Therefore, according to this structure, the vibration transmission between the ultrasonic microphone 4 and the frame 7 can be further effectively suppressed.

[0152] In addition, in the present embodiment, the entire circumferential direction of the first cylindrical portion 56 provided on the front end side in the axial direction abuts against the ultrasonic microphone 4 and the frame 7. That is, the small-diameter portion 59 is not provided on the first cylindrical portion 56. On the other hand, the small-diameter portion 59 is provided on the second cylindrical portion 57 adjacent to the first cylindrical portion 56 on the base end side in the axial direction. Thus, erroneous detection caused by the infiltration of water into the front end portion in the axial direction of the ultrasonic sensor 1 can be avoided as much as possible.

[0153] (Second Embodiment)

[0154] Below, refer to Fig.11The second embodiment is described. In addition, in the following description of the second embodiment, the parts different from the first embodiment are mainly described. In addition, in the first embodiment and the second embodiment, the same or equivalent parts are marked with the same figure marks. Therefore, in the following description of the second embodiment, regarding the constituent elements with the same figure marks as the first embodiment, as long as there is no technical contradiction or special additional description, the description in the first embodiment can be appropriately quoted. The same applies to the other embodiments after the third embodiment.

[0155] exist Fig.11 In the figure, arrow R indicates radial direction. Fig.11 As shown, in this embodiment, a plurality of protrusions 591 protruding in the radial direction are provided on the small diameter portion 59. Specifically, the protrusions 591 are formed into a substantially hemispherical shape, or a substantially conical shape with a circular front end. The plurality of protrusions 591 are arranged in the axial direction and the circumferential direction. According to this structure, the assembled state of the secondary assembly can be reliably maintained, and the vibration transmission between the ultrasonic microphone 4 and the frame 7 can be well suppressed.

[0156] (Third Embodiment)

[0157] Below, refer to Fig.12 The third embodiment is described. This embodiment corresponds to a method in which a part of the second embodiment described above is changed. Fig.12 In, with Fig.11 Likewise, arrow R indicates a radial direction.

[0158] In this embodiment, similarly to the second embodiment, a plurality of protrusions 591 are provided on the small diameter portion 59 to protrude in the radial direction. In this embodiment, the protrusions 591 have a track-like shape, a partial ring-like shape, or a thread-like shape extending in the circumferential direction. The plurality of protrusions 591 are arranged in the axial direction. This structure can also achieve the same effect as the second embodiment.

[0159] (Fourth Embodiment)

[0160] Below, refer to Fig.13 The fourth embodiment is described. This embodiment corresponds to a change in Fig. 9A The embodiment shown is a part of the structure of the first embodiment described above.

[0161] In this embodiment, the front end side protruding portion 77 as the through hole facing portion 78 has an area reduction structure that reduces the contact area with the inner edge V51. Fig.13As shown, the front end protruding portion 77 has a tapered structure as an area reduction structure. That is, the front end protruding portion 77 is formed so that the axial dimension decreases as it moves toward the radial direction and is smaller than the plate thickness of the front bumper V3 at the terminal portion 77f. More specifically, the front end protruding portion 77 is formed so that the axial dimension decreases linearly from the root portion 77d to the terminal portion 77f.

[0162] The front end protrusion 77 is formed such that the axial dimension from the root 77d to the terminal 77f is smaller than the plate thickness of the front bumper V3. That is, the tapered structure provided at the front end protrusion 77 is configured so that the entirety thereof is accommodated in the mounting hole V5 in the mounted state.

[0163] According to this structure, the contact area between the front end protruding portion 77 and the inner edge V51 of the mounting hole V5 is reduced, thereby effectively suppressing the vibration transmission in the second transmission path. Therefore, according to this embodiment, the vibration transmission between the ultrasonic sensor 1 and the front bumper V3 and the generation of false detection caused by the vibration transmission can be effectively suppressed.

[0164] (Fifth Embodiment)

[0165] Below, refer to Fig.14 The fifth embodiment is described below. This embodiment corresponds to a mode in which a part of the fourth embodiment described above is changed.

[0166] In this embodiment, if Fig.14 As shown, the terminal end portion 77f is formed into a curved surface convex toward the radial direction. That is, Fig.14 The tapered structure shown has a convex surface 781 at its front end in the radial direction.

[0167] According to this structure, the contact area between the front end protruding portion 77 and the inner edge V51 of the mounting hole V5 is further reduced, so the vibration transmission in the second transmission path can be further effectively suppressed. Therefore, according to this embodiment, the vibration transmission between the ultrasonic sensor 1 and the front bumper V3 and the generation of false detection caused by the vibration transmission can be further effectively suppressed.

[0168] (Variation Example)

[0169] The present disclosure is not limited to the above-mentioned embodiments. Therefore, the above-mentioned embodiments can be appropriately changed. Representative modified examples are described below. In the following description of the modified examples, the differences from the above-mentioned embodiments are mainly described. In addition, in the above-mentioned embodiments and the modified examples, the same or equivalent parts are marked with the same figure marks. Therefore, in the description of the following modified examples, with respect to the constituent elements with the same figure marks as those in the above-mentioned embodiments, the description in the above-mentioned embodiment can be appropriately cited as long as there is no technical contradiction or special additional description.

[0170] In the above embodiment, for the sake of convenience, the ultrasonic sensor 1 mounted on the front bumper V3 is described. However, the present disclosure is not limited to this embodiment. That is, the structure of the ultrasonic sensor 1 mounted on the rear bumper V4 can also be easily understood from the description of the above embodiment.

[0171] The ultrasonic sensor 1 is not limited to the front bumper V3 and the rear bumper V4. Specifically, for example, the ultrasonic sensor 1 may be mounted on the vehicle body panel V2. That is, the mounting hole V5 may be provided on the vehicle body panel V2.

[0172] The ultrasonic sensor 1 is not limited to a structure capable of transmitting and receiving ultrasonic waves. That is, for example, the ultrasonic sensor 1 may have a structure capable of transmitting only ultrasonic waves. Alternatively, the ultrasonic sensor 1 may have a function of receiving only reflected waves of ultrasonic waves, i.e., detection waves, transmitted from other ultrasonic transmitters and reflected by surrounding objects.

[0173] The structure of each part in the ultrasonic sensor 1 is not limited to the above-mentioned specific example. Specifically, for example, the materials constituting each part can be appropriately changed from the above-mentioned specific example. In addition, a plurality of components formed of the same material can also be formed of different materials. Similarly, a plurality of components formed of different materials can also be formed of the same material.

[0174] In addition, a plurality of components formed seamlessly and integrally with each other may be formed by bonding mutually independent parts. Similarly, a plurality of components formed by bonding mutually independent parts may be formed seamlessly and integrally with each other.

[0175] The specific structure of the sensor housing 3 is not limited to the above-mentioned specific example. That is, for example, the structure and the extending direction of the connector part 32 can be appropriately changed. In addition, the shape of the microphone support part 33 is not limited to a roughly cylindrical shape, and can also be a roughly elliptical cylindrical shape, a roughly long cylindrical shape, a roughly polygonal cylindrical shape, etc.

[0176] The outer shape of the ultrasonic microphone 4, that is, the microphone case 42, is not limited to a substantially cylindrical shape, and may be a substantially elliptical column shape, a substantially regular polygonal column shape, etc. The electromechanical transducer constituting the ultrasonic element 41 is also not limited to a piezoelectric element.

[0177] The specific structure of the buffer member 5 is not limited to the above-mentioned specific example. For example, the shape of the buffer member 5 is not limited to a substantially cylindrical shape, and may be a substantially elliptical cylindrical shape, a substantially elongated cylindrical shape, a substantially polygonal cylindrical shape, or the like.

[0178] The buffer member 5 may also be assembled to the sensor body 2 as a primary assembly to form a secondary assembly, similarly to the frame 7. In this case, for example, the ultrasonic microphone 4 is supported by the microphone support portion 33 in the sensor housing 3 without the buffer member 5. The buffer member 5 is formed into a cylindrical shape having an axial dimension substantially the same as that of the ultrasonic microphone 4, that is, the microphone housing 42.

[0179] The large diameter portion 58 and the cylindrical portion 72 may be disposed opposite to each other with a gap therebetween. That is, the large diameter portion 58 and the cylindrical portion 72 may be disposed so as to be non-contacted in whole or in part in the circumferential direction.

[0180] The second tubular portion 57 having the small diameter portion 59 may be provided at least at a position corresponding to the distal end protruding portion 77 in the axial direction. This can satisfactorily suppress the transmission of vibration in the second transmission path described above.

[0181] A large diameter portion 58 may be provided on at least a portion of the circumference of the first cylindrical portion 56, and a small diameter portion 59 may be provided on the entire circumference of the second cylindrical portion 57. That is, in this case, the vibration absorber includes a large diameter portion (58) provided to contact the ultrasonic microphone (4) and the sensor mounting tool and to be sandwiched between the ultrasonic microphone and the sensor mounting tool, and a small diameter portion (59) provided adjacent to the large diameter portion on the base end side of the large diameter portion in the axial direction and having an outer diameter smaller than that of the large diameter portion centered on the central axis (CL), and the small diameter portion is provided across the entire circumference of the vibration absorber.

[0182] The specific structures of the frame 7 and the retainer 8 as components for mounting the ultrasonic sensor 1 on a plate-shaped vehicle body component (e.g., the front bumper V3) are not limited to the above-mentioned specific examples. Specifically, for example, the detailed structures of the frame 7 and / or the retainer 8 can be appropriately changed from the above-mentioned specific examples.

[0183] By providing a fixing mechanism or a fixing portion for fixing the frame 7 to the vehicle body member on the frame 7 itself, the retainer 8 can be omitted.

[0184] The concave-convex relationship between the frame side snap-in portion 77a and the bumper side snap-in portion V52 can be set oppositely. That is, the frame side snap-in portion 77a can be set as a convex portion having a larger radial protrusion than other portions in the front end side protrusion setting portion 77. In this case, the bumper side snap-in portion V52 can be set as a portion of the mounting hole V5 with an enlarged aperture.

[0185] The above-mentioned area reduction structure is not limited to the tapered structure in the front end side protruding portion 77. That is, for example, a plurality of protrusions protruding in the radial direction may be provided on the surface of the front end side protruding portion 77 as the through hole opposing portion 78, which is close to and opposite to the inner edge V51 of the terminal portion 77f. As a result, the contact area between the front end side protruding portion 77 and the inner edge V51 of the mounting hole V5 is reduced, so that the vibration transmission in the second transmission path can be well suppressed.

[0186] The above-mentioned area reduction structure may be provided over the entire circumferential direction of the front end side protruding portion 77. Alternatively, the above-mentioned area reduction structure may be provided at least at positions corresponding to both ends of the diaphragm 43 in the longitudinal direction.

[0187] The elements constituting the above-mentioned embodiments are not necessarily essential elements, except for the cases where it is specifically clearly stated that they are essential and the cases where it is clearly considered to be essential in principle. In addition, when referring to the number, amount, range and other numerical values ​​of the constituent elements, the present disclosure is not limited to the specific numerical values, except for the cases where it is specifically clearly stated that they are essential and the cases where it is clearly limited to specific numerical values ​​in principle. Similarly, when referring to the shapes, directions, positional relationships, etc. of the constituent elements, the present disclosure is not limited to the shapes, directions, positional relationships, etc., except for the cases where it is specifically clearly stated that they are essential and the cases where it is limited to specific shapes, directions, positional relationships, etc. in principle.

[0188] The modified examples are not limited to the above-mentioned examples. That is, for example, in addition to the above-mentioned examples, multiple embodiments can be combined with each other as long as they are not technically contradictory. Similarly, multiple modified examples can be combined with each other as long as they are not technically contradictory.

Claims

1. A vibration absorber, which is a member for mounting an ultrasonic sensor on a plate-shaped vehicle body member, wherein: The ultrasonic sensor includes a columnar ultrasonic microphone extending in an axial direction parallel to a central axis, and the vibration absorber is provided on the ultrasonic sensor in such a manner that the vibration absorber is sandwiched between a sensor mounting tool provided to surround a side of the ultrasonic microphone and the ultrasonic microphone when the ultrasonic sensor is mounted on the vehicle body component. The vibration absorber has: a large diameter portion arranged to contact the ultrasonic microphone and the sensor mounting tool and to be sandwiched between the ultrasonic microphone and the sensor mounting tool; and The small diameter portion is arranged adjacent to the large diameter portion in the circumferential direction surrounding the central axis, and the outer diameter centered on the central axis is formed smaller than that of the large diameter portion. The pair of large diameter portions are arranged opposite to each other across the central axis. The pair of small diameter portions are arranged opposite to each other across the central axis. The vibration absorber is configured such that an arrangement direction of the pair of large diameter portions sandwiching the central axis and an arrangement direction of the pair of small diameter portions sandwiching the central axis are orthogonal to each other.

2. The vibration absorber according to claim 1, wherein: One of the pair of large diameter portions, one of the pair of small diameter portions, the other of the pair of large diameter portions, and the other of the pair of small diameter portions are arranged adjacent to each other in sequence in the circumferential direction.

3. The vibration absorber according to claim 2, wherein: The large diameter portion is formed so that the length in the circumferential direction is shorter than the length in the circumferential direction of the small diameter portion.

4. The vibration absorber according to any one of claims 1 to 3, wherein have: a first cylindrical portion provided on the front end side in the axial direction so as to be in contact with the ultrasonic microphone and the sensor mounting tool and to be sandwiched between the ultrasonic microphone and the sensor mounting tool; and The second cylindrical portion is provided adjacent to the first cylindrical portion at the base end side in the axial direction. The small diameter portion is provided on the second cylindrical portion.

5. The vibration absorber according to any one of claims 1 to 3, wherein The ultrasonic microphone comprises a diaphragm, and the diaphragm has a thickness direction in the axial direction. The shape of the diaphragm in a plane perpendicular to the central axis has a long side direction and a short side direction perpendicular to each other. The small diameter portion is provided at a position corresponding to both end portions of the diaphragm in the longitudinal direction.

6. The vibration absorber according to any one of claims 1 to 3, wherein The invention further comprises a plurality of protrusions, wherein the plurality of protrusions are provided to protrude from the small diameter portion along a radial direction extending radially from the central axis.

7. The vibration absorber according to any one of claims 1 to 3, wherein The vehicle body member is a metal plate.

8. The vibration absorber according to any one of claims 1 to 3, wherein The sensor mounting tool has a cylindrical portion, the cylindrical portion is provided to surround the ultrasonic microphone, and is accommodated in a through hole formed in the vehicle body member in the vehicle-mounted state. The small diameter portion is formed so that a gap between the small diameter portion and the cylindrical portion is larger than a gap between the large diameter portion and the cylindrical portion.

9. An ultrasonic sensor comprising: The vibration absorber according to claim 8; The sensor installation tool mentioned above; and The vibration isolator is formed of a synthetic resin elastic material and is arranged to be sandwiched between the sensor mounting tool and the vehicle body member. The sensor mounting tool has a flange portion, and the flange portion is provided to protrude in a radial direction extending radially from the central axis at one end portion of the cylindrical portion in the axial direction. The flange portion is formed with an outer diameter larger than that of the through hole so as to face a portion of the outer surface of the vehicle body member surrounding the through hole in the vehicle-mounted state. The vibration isolation member is provided so as to be sandwiched between the flange portion and the vehicle body member.

10. The ultrasonic sensor according to claim 9, wherein: A sensor fixture is further provided, wherein the sensor fixture is inserted between the cylindrical portion and the vehicle body component in a state where the cylindrical portion is inserted through the through hole, and is clamped between the cylindrical portion and the vehicle body component in the vehicle-mounted state. The sensor fixture is formed into a U shape by a pair of extended portions and a connecting portion, wherein the pair of extended portions are extended in a direction intersecting the central axis and are opposed to each other across the central axis, and the connecting portion connects one end portions of the pair of extended portions to each other. The cylindrical portion is sandwiched between the pair of extending portions. The ultrasonic sensor is configured such that the arrangement direction of the pair of small-diameter portions sandwiching the central axis and the arrangement direction of the pair of extended portions sandwiching the central axis are orthogonal to each other.

11. The ultrasonic sensor according to claim 9 or 10, wherein: The through-hole opposing portion in the cylindrical portion has an area reduction structure, wherein the through-hole opposing portion is contactably close to and opposed to the inner edge of the through-hole in the vehicle-mounted state, and the area reduction structure reduces the contact area between the through-hole opposing portion and the inner edge.

12. The ultrasonic sensor according to claim 11, wherein: The cylindrical portion includes a cylindrical main body and a protruding portion as the through-hole opposing portion, wherein the main body extends along the central axis, and the protruding portion is integrally combined with the main body and protrudes in the radial direction. The protruding portion is extended along the circumferential direction. The area reduction structure is a tapered structure in which a dimension of the protruding portion in the axial direction decreases toward the radial direction and a distal end portion in the radial direction is smaller than a plate thickness of the vehicle body member.

Images