Sensor assembly

Abstract

To provide a sensor assembly capable of accurately positioning a bracket and a damping material.SOLUTION: The sensor assembly 1 transmits a transmission wave Sa from a sensor unit 10 disposed in close contact with the back surface of the metal plate 2 to the surroundings via the metal plate 2, and detects an object 3 based on a reflected wave Sb of the transmission wave Sa reflected by the object 3. A sensor assembly 1 includes a bracket 11 for housing a sensor unit 10, a damping material 34 attached to a back surface of a metal plate 2 to suppress transmission of vibration in a direction from the metal plate 2 toward the sensor unit 10, and a holder 39 which is positioned and attached to the damping material 34 and to which the bracket 11 is attached.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a sensor assembly for wirelessly sensing an object. [Background technology]

[0002] As disclosed in Patent Document 1, an ultrasonic sensor is known that is disposed on the rear surface of a thin plate of a vehicle and wirelessly detects objects around the vehicle. This ultrasonic sensor transmits pulsed ultrasonic waves into the surrounding area by exciting the thin plate. When ultrasonic waves are transmitted, the thin plate is excited by a direct wave that propagates directly through the plate and a reflected wave that reflects from the object. The ultrasonic sensor detects the object from the excitation of the thin plate by the direct wave and the reflected wave. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-100881 Summary of the Invention [Problem to be solved by the invention]

[0004] An ultrasonic sensor, for example, includes a sensor unit that detects vibrations in a thin plate and a bracket that supports the sensor unit. The ultrasonic sensor is attached so that the bracket is fixed to the back surface of the thin plate with the sensor unit in contact with the back surface of the thin plate. In this case, it has been considered to place a vibration-damping material between the bracket and the thin plate to prevent the bracket from shaking significantly due to vibrations of the thin plate. However, because the bracket and the vibration-damping material are attached to the thin plate separately, it has been difficult to accurately position the bracket and the vibration-damping material. [Means for solving the problem]

[0005] The sensor assembly that solves the above problem is configured to transmit a transmission wave from a sensor unit placed in close contact with the back surface of a metal plate to the surrounding area through the metal plate, and detect the object based on the reflected wave of the transmission wave reflected by the object, and includes a bracket that houses the sensor unit, a vibration-damping material that is attached to the back surface of the metal plate to suppress the transmission of vibrations in the direction from the metal plate toward the sensor unit, and a holder that is positioned and attached to the vibration-damping material and to which the bracket is attached. [Effects of the Invention]

[0006] The present invention can accurately position the bracket and the vibration-damping material. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a perspective view of a sensor assembly according to one embodiment. [Figure 2] FIG. 10 is a schematic diagram showing an example of mounting a sensor assembly. [Figure 3] FIG. 2 is an exploded perspective view of the sensor assembly. [Figure 4] FIG. 7 is a cross-sectional view taken along line IV-IV shown in FIG. 6. [Figure 5] FIG. 2 is a perspective view of a bracket and a spring holding portion. [Figure 6] FIG. 1 is a front view of a sensor assembly attached to a metal plate. [Figure 7] FIG. 2 is a rear view of the sensor assembly. [Figure 8] FIG. 10 is an explanatory diagram illustrating how the sensor part is attached to the holder. DETAILED DESCRIPTION OF THE INVENTION

[0008] An embodiment of the present disclosure will be described below. (Sensor assembly 1) As shown in FIG. 1, the sensor assembly 1 is attached and fixed to the rear surface of a predetermined metal plate 2. The sensor assembly 1 detects surrounding objects 3 based on communication signals transmitted and received via the metal plate 2. In this way, the sensor assembly 1 wirelessly detects surrounding objects 3. The sensor assembly 1 is, for example, an ultrasonic sensor that uses ultrasonic waves as the wireless communication signal.

[0009] The sensor assembly 1 transmits a transmission wave Sa to the surroundings via the metal plate 2. If an object 3 is present around the metal plate 2, the transmission wave Sa is reflected by the object 3. The sensor assembly 1 detects the object 3 based on a reflected wave Sb of the transmission wave Sa reflected by the object 3. The sensor assembly 1 detects, for example, the presence or absence of the object 3 and the distance to the object 3.

[0010] (Example of sensor assembly 1 installation) As shown in FIG. 2, the sensor assembly 1 is used in, for example, a vehicle 5. Specifically, the sensor assembly 1 is attached and fixed to the back surface of a door panel 6, which is a metal plate 2. The sensor assembly 1 detects an object 3 present in the surrounding area while the vehicle 5 is traveling, for example. Note that the sensor assembly 1 is not limited to being used in the vehicle 5, and may also be used in, for example, a charging device for the vehicle 5 or roadway facilities. Furthermore, the metal plate 2 is preferably a flat design plate 7 that can be seen from the outside as a design.

[0011] (Main part of sensor assembly 1) 3 and 4, the sensor assembly 1 has a sensor component 9 as a group of components that detect the object 3. The sensor component 9 has, for example, a sensor unit 10 that senses the object 3, a bracket 11 that houses the sensor unit 10, and a pressing mechanism 12 that presses the sensor unit 10 from behind to bring it into close contact with the metal plate 2. The sensor component 9 is constructed by assembling the sensor unit 10 and the pressing mechanism 12 to the bracket 11.

[0012] The sensor unit 10 accommodates various sensor elements within a housing. The sensor unit 10 has a body portion 14 forming a large diameter portion, a tip portion 15 disposed at the tip of the body portion 14, and a connector portion 16 to which an external cable (not shown) is electrically connected. The body portion 14 forms the main body portion of the sensor unit 10. The body portion 14 is formed, for example, in a cylindrical shape and is housed inside the bracket 11. The tip portion 15 is formed in a cylindrical shape with a smaller diameter than the body portion 14. The tip portion 15 is disposed so that a detection surface 17 at the tip is in close contact with the rear surface of the metal plate 2.

[0013] (Pressing mechanism 12) 3 and 4, the pressing mechanism 12 includes, for example, a spring 19, a pusher 20, and a spring holder 21. The spring 19 is disposed between the pusher 20 and the spring holder 21, and is, for example, a tapered spring. The spring 19 is positioned by a bulge 22 formed inside the pusher 20.

[0014] A plurality of guide protrusions 23 are formed on the outer surface of the pusher 20 to guide the movement of the pusher 20 in the axial direction (the X-axis direction in FIG. 3, etc.) inside the bracket 11. The plurality of guide protrusions 23 are arranged around the center of the pusher 20 at predetermined intervals.

[0015] As shown in Fig. 5, spring holding portion 21 is formed in the shape of a cap that closes the end face of bracket 11. A plurality of (three in this example) protrusions 24 (only two are shown in Fig. 5) are formed inside spring holding portion 21 and engage with bracket 11 to prevent spring holding portion 21 from coming off. The plurality of protrusions 24 are arranged around the center of spring holding portion 21 at predetermined intervals.

[0016] (Bracket 11) 3 to 5, bracket 11 has a bracket main body 26 that houses sensor unit 10 therein. Bracket main body 26 is formed, for example, in a substantially cylindrical shape without a bottom. Bracket main body 26 houses sensor unit 10 in an internal housing portion 27 so that it can slide in the axial direction of bracket main body 26 (the X-axis direction in FIG. 3, etc.).

[0017] 3 and 5, bracket 11 has guide portions 28 that guide linear movement of pusher 20 in the axial direction (X-axis direction in FIG. 3, etc.). In this example, guide portions 28 have a shape that bulges out a predetermined amount from the outer peripheral surface of bracket main body 26, and have groove shapes therein into which guide protrusions 23 of pusher 20 are slidably fitted. Each of the multiple guide protrusions 23 of pusher 20 is fitted movably in the axial direction (X-axis direction in FIG. 3, etc.) to a guide portion 28 that constitutes a set of multiple guide portions 28 formed on bracket 11.

[0018] A recessed portion 29 having a shape lower than the guide portion 28 is formed on the outer peripheral surface of the bracket 11. The recessed portion 29 is disposed between adjacent guide portions 28 in the circumferential direction of the bracket 11. Each of the guide portions 28 is formed with a notch 30 into which the protrusion 24 of the spring holding portion 21 is engaged.

[0019] When attaching spring retaining portion 21 to bracket 11, first, spring retaining portion 21 is inserted toward the back of bracket 11 while aligning protrusion 24 of spring retaining portion 21 with recessed portion 29 of bracket 11. Next, spring retaining portion 21 is rotated in one circumferential direction, so that protrusion 24 enters notch 30 through slit portion 31 formed in the side wall of guide portion 28. Then, spring retaining portion 21 moves in the opposite insertion direction due to the biasing force of spring 19, and protrusion 24 engages with notch 30, thereby fixing spring retaining portion 21 to bracket 11.

[0020] (damping material 34) 3 and 4, the sensor assembly 1 includes a damping material 34 that suppresses transmission of vibrations in the direction from the metal plate 2 toward the sensor unit 10 (the direction of arrow F in FIG. 4, etc.). The damping material 34 is attached to the back surface of the metal plate 2. In this example, the damping material 34 is disposed between the metal plate 2 and the bracket 11, thereby suppressing transmission of vibrations from the metal plate 2 to the sensor unit 10. The damping material 34 is formed in a sheet shape. The damping material 34 has an opening 35 that allows the sensor unit 10 to reach the metal plate 2. The opening 35 is disposed, for example, in the center of the damping material 34.

[0021] The vibration-damping material 34 has a raised portion 36 that is disposed in the center of the vibration-damping material 34 and that protrudes toward the bracket 11, and a substantially circular flat portion 37 that is disposed around the raised portion 36. The raised portion 36 has an opening hole 35 disposed in the center and is formed to protrude a predetermined amount from the flat portion 37. The flat portion 37 is brought into close contact with the metal plate 2 when the sensor assembly 1 is attached to the metal plate 2.

[0022] The damping material 34 is made of, for example, a soft material. For example, a butyl sheet is used as the damping material 34. The butyl sheet may be, for example, a sheet to which butyl has been added. In the case of a butyl sheet, the damping material 34 can be attached to the rear surface of the metal plate 2 due to its own adhesiveness.

[0023] 6, the damping material 34 is formed in a circular shape when viewed from the front from the inside of the metal plate 2. The sensor component 9 and the damping material 34 are arranged coaxially. The sensor component 9 is arranged in the center of the damping material 34. As a result, the distance from the center of the sensor component 9 to the periphery of the damping material 34 is the same at all positions.

[0024] (Holder 39) 3 and 4, the sensor assembly 1 includes a holder 39 that is integrated with the damping material 34 and to which the bracket 11 can be attached. The holder 39 in this example is positioned and attached to the damping material 34, and the bracket 11 is attached to it. The holder 39 is made of, for example, a hard material. The holder 39 is disposed, for example, in the center of the damping material 34. In other words, the holder 39 is disposed coaxially with the damping material 34.

[0025] The holder 39 has a base 40 that is sandwiched between the metal plate 2 and the vibration-damping material 34. The base 40 has a planar shape. The holder 39 has a holder hole 41 that is positioned coaxially with the opening hole 35 when attached to the vibration-damping material 34. In this example, the base 40 is formed in an annular shape by having the holder hole 41 in the center. The holder hole 41 is formed in a circular shape, similar to the opening hole 35 of the vibration-damping material 34. The sensor unit 10 is exposed to the metal plate 2 through the opening hole 35 and the holder hole 41, and is thereby in close contact with the metal plate 2.

[0026] The holder 39 has a positioning protrusion 42 for positioning the holder 39 relative to the vibration-damping material 34. In the present example, the positioning protrusion 42 protrudes from at least a portion of the periphery of the holder hole 41 and is fitted into the opening hole 35 of the vibration-damping material 34. The positioning protrusion 42 in the present example is disposed over the entire periphery of the holder hole 41, and is thus formed in a circumferential shape.

[0027] As shown in Fig. 7, the base 40 of the holder 39 is housed in a housing portion 36a formed inside the raised portion 36 of the vibration-damping material 34. A predetermined gap W is provided between the inner circumferential surface of the holder hole 41 and the tip end 15 of the sensor unit 10. The gap W is formed over the entire circumferential area centered on the tip end 15 of the sensor unit 10. The gap W is provided to separate the tip end 15 of the sensor unit 10 from the holder hole 41 in order to ensure the detection accuracy of the sensor unit 10.

[0028] (Interposition member 43) 3 and 7, the sensor assembly 1 includes an interposing member 43 disposed between the metal plate 2 and the holder 39 to press the holder 39 against the vibration-damping material 34. The interposing member 43 is formed in a ring shape with a hole in the center for passing the sensor unit 10 through. The interposing member 43 is disposed between the base 40 of the holder 39 and the metal plate 2. The interposing member 43 is preferably, for example, double-sided tape 43a. In the case of double-sided tape 43a, the interposing member 43 is preferably formed to have a sufficient area to ensure a sufficient adhesive area with the metal plate 2.

[0029] (Bracket support part 44) 3 and 4, the holder 39 has a bracket support portion 44 disposed to penetrate the vibration-damping material 34 in order to support the bracket 11. The bracket support portion 44 is inserted into a through-hole 34a formed in the vibration-damping material 34 and reaches the bracket 11. In this example, the bracket 11 is fixed to the bracket support portion 44. The bracket support portion 44 is a protrusion extending from the base 40, and multiple bracket support portions 44 (four in this example) are formed. The bracket support portion 44 is disposed at a position on the base 40 radially outward of the positioning protrusions 42.

[0030] (locking mechanism 45) 3 and 4, a locking mechanism 45 that fixes the bracket 11 to the holder 39 is provided between the bracket 11 and the bracket support portion 44. The locking mechanism 45 fixes the bracket 11 to the holder 39 by engaging a protrusion 48 formed on one of the bracket 11 and the bracket support portion 44 with a recess 47 formed on the other of the bracket 11 and the holder 39. In this example, the protrusion 48 is formed on the bracket support portion 44, and the recess 47 is formed on the bracket 11.

[0031] The protrusions 48 are formed on each bracket support portion 44 and are arranged on the inner surface of the bracket support portion 44. The recesses 47 are holes that penetrate the recessed portion 29 of the bracket 11. A plurality of pairs of bracket support portion 44 and recesses 47 are arranged at predetermined intervals around the center of the sensor component 9.

[0032] (Operation of the embodiment) Next, the operation of the sensor assembly 1 of this embodiment will be described. 8, the bracket 11 of the sensor component 9 is attached and fixed to the holder 39 which is aligned with and fixed to the vibration-damping material 34. In this way, since the bracket 11 of the sensor component 9 is attached to the holder 39 whose position is determined with precision relative to the vibration-damping material 34, the position of the bracket 11 with respect to the vibration-damping material 34 is also determined with precision. Therefore, it is possible to position the bracket 11 and the vibration-damping material 34 with precision.

[0033] Moreover, the holder 39 supports the bracket 11 by means of a bracket support portion 44 that penetrates the vibration-damping material 34. Specifically, the bracket support portion 44 is inserted into a through-hole 34a formed in the vibration-damping material 34 so as to reach the bracket 11, and the bracket 11 is fixed by a protrusion 48 of this bracket support portion 44. For this reason, the shape of the bracket 11 does not need to be a shape in which the tips of the legs extending radially outward from the center of the bracket 11 are fixed to the metal plate 2 by a tape member. This allows the bracket 11 to be made smaller.

[0034] 4, the holder 39 is attached to the metal plate 2 by interposing an interposing member 43 between the metal plate 2 and the holder 39. In this way, the interposing member 43 is disposed between the metal plate 2 and the holder 39, making it possible to reduce the likelihood of a gap being formed between the metal plate 2 and the holder 39. In addition, the thickness of the interposing member 43 makes it possible to press the holder 39 against the vibration-damping material 34. Therefore, the position of the holder 39 is determined with high precision, which contributes to improving the positional precision between the bracket 11 and the vibration-damping material 34.

[0035] Incidentally, since the metal plate 2 is a decorative plate 7 having a design feature, it is not possible to form structures such as protrusions for fixing the sensor assembly 1. However, in this example, the sensor assembly 1 is fixed to the metal plate 2 by utilizing the adhesiveness of the vibration-damping material 34 and by using double-sided tape 43a as the interposing member 43, so there is no need to form structures on the metal plate 2 for fixing the sensor assembly 1. Therefore, it is possible to firmly fix the sensor unit 10 to the metal plate 2 without using a method for forming structures such as protrusions on the metal plate 2.

[0036] In addition, in this example, the sensor assembly 1 is provided with a locking mechanism 45 for fixing the bracket 11 to the holder 39. Therefore, the bracket 11 is firmly fixed to the holder 39 by the locking mechanism 45. This makes it possible to make the bracket 11 less likely to fall off the holder 39, and further makes it possible to make it less likely that the bracket 11 will rattle relative to the holder 39.

[0037] (Effects of the embodiment) According to the sensor assembly 1 of the above embodiment, the following effects can be obtained. (1) The sensor assembly 1 includes a bracket 11 that houses the sensor unit 10, a vibration-damping material 34 that is attached to the back surface of the metal plate 2 to suppress the transmission of vibrations in the direction from the metal plate 2 toward the sensor unit 10, and a holder 39 that is positioned and attached to the vibration-damping material 34 and to which the bracket 11 is attached.

[0038] According to this configuration, the bracket 11 of the sensor assembly 1 is attached and fixed to the holder 39, which is positioned and attached to the vibration-damping material 34. Therefore, since the bracket 11 of the sensor assembly 1 is attached to the holder 39, which is positioned with high precision relative to the vibration-damping material 34, the positions of the bracket 11 and the vibration-damping material 34 are also determined with high precision. Therefore, the bracket 11 and the vibration-damping material 34 can be positioned with high precision.

[0039] (2) The sensor assembly 1 includes an interposing member 43 disposed between the metal plate 2 and the holder 39. With this configuration, the interposing member 43 disposed between the vibration-damping material 34 and the holder 39 eliminates any gap between the metal plate 2 and the holder 39, and presses the holder 39 against the vibration-damping material 34 to prevent rattling.

[0040] (3) The vibration-damping material 34 has an opening 35 that allows the sensor unit 10 to reach the metal plate 2. The holder 39 has a holder hole 41 that is positioned coaxially with the opening 35 when attached to the vibration-damping material 34. When the bracket 11 is attached to the holder 39, the sensor unit 10 is exposed to the metal plate 2 through the opening 35 and the holder hole 41, and is thereby in close contact with the metal plate 2. With this configuration, the vibration-damping material 34 is disposed around the entire periphery of the sensor unit 10, thereby improving the vibration resistance of the sensor unit 10.

[0041] (4) The holder 39 has a positioning protrusion 42 that protrudes from at least a portion of the periphery of the holder hole 41 and is fitted into the opening 35 of the vibration-damping material 34. With this configuration, the positioning protrusion 42 enables the holder 39 to be aligned with the vibration-damping material 34 with high precision. This further contributes to aligning the bracket 11 and the vibration-damping material 34 with high precision.

[0042] (5) The holder 39 has a bracket support portion 44 that is disposed to penetrate the vibration-damping material 34 in order to support the bracket 11. With this configuration, it is possible to support the bracket 11 at a position radially inside the vibration-damping material 34. Therefore, the bracket 11 does not need to have a shape that is supported by the metal plate 2 by arms that extend radially outward, for example. Therefore, because the bracket 11 has a shape that does not have arms, the size of the bracket 11 can be reduced.

[0043] (6) A locking mechanism 45 is provided between the bracket 11 and the bracket support portion 44. The locking mechanism 45 fixes the bracket 11 to the holder 39 by engaging a protrusion 48 formed on one of the bracket 11 and the bracket support portion 44 with a recess 47 formed on the other of the bracket 11 and the bracket support portion 44. This configuration makes it possible to firmly fix the bracket 11 to the holder 39 using the locking mechanism 45, making it difficult for the bracket 11 to fall off the holder 39.

[0044] (7) The sensor assembly 1 includes a pressing mechanism 12 that presses the sensor unit 10 from the rear side when the sensor unit 10 and the holder 39 are assembled, thereby bringing the sensor unit 10 into close contact with the metal plate 2. With this configuration, the pressing mechanism 12 presses the sensor unit 10 against the metal plate 2, enabling accurate communication of the sensor unit 10 via the metal plate 2. This contributes to improving the detection accuracy of the sensor unit 10.

[0045] (8) The metal plate 2 is a planar decorative plate 7 that is visible from the outside as a design. The sensor unit 10 in this example is fixed to the metal plate 2 by utilizing the adhesiveness of the vibration-damping material 34 and the adhesiveness of the double-sided tape 43a. Therefore, it is not necessary to provide the metal plate 2 with a shape or structure for fixing the sensor assembly 1 to the metal plate 2. Therefore, even if a decorative plate 7 that cannot be formed with a shape or structure that affects the design is used as the metal plate 2, the sensor unit 10 can be securely attached to the decorative plate 7.

[0046] (Other embodiments) This embodiment can be modified as follows: This embodiment and the following modifications can be combined and implemented within the scope of technical compatibility.

[0047] The shape of the vibration-damping material 34 is not limited to a circular shape, and may be changed to another shape, such as a square shape. The vibration-damping material 34 does not necessarily have to be adhesive, and may be made of a non-adhesive material. In this case, it is preferable to use double-sided tape 43a for the interposing member 43, and to fix the sensor assembly 1 to the metal plate 2 with the double-sided tape 43a.

[0048] The vibration-damping material 34 may have a shape that does not have the protrusions 36. The interposing member 43 may be a member other than tape. The interposing member 43 may be omitted.

[0049] The opening hole 35 and the holder hole 41 do not necessarily have to be disposed at the center when viewed from the front of the sensor assembly 1, but may be disposed at a position other than the center. The positioning protrusion 42 is not limited to a structure in which it is engaged with the opening 35 of the vibration-damping material 34. For example, a slit may be formed at a predetermined position in the vibration-damping material 34, and the positioning protrusion 42 may be engaged with this slit.

[0050] The positioning protrusion 42 is not limited to a ring-shaped protrusion, but may be, for example, a tongue-shaped protrusion. A plurality of positioning protrusions 42 may be formed.

[0051] The positioning protrusion 42 may be omitted. The number of bracket support portions 44 is not limited to a plurality, and may be only one. The bracket support portion 44 may be modified into various shapes as appropriate as long as it is capable of supporting the bracket 11.

[0052] The bracket support portion 44 may be formed integrally with the positioning protrusion 42. In this way, the function of supporting the bracket 11 and the function of positioning the holder 39 relative to the vibration-damping material 34 may be achieved by a single shape.

[0053] The bracket support portion 44 is not limited to a structure in which the bracket 11 is fixed to the holder 39 by the protrusions 48, and may be a structure in which the bracket 11 is fixed to the holder 39 by press-fitting, for example. Furthermore, the structure in which the bracket support portion 44 fixes the bracket 11 to the holder 39 may use various structures such as a snap fit.

[0054] The holder 39 may be shaped so as to be attached to the edge of the vibration damping material 34 . The pressing mechanism 12 is not limited to a structure using a metal spring 19, but may be a structure using a resin spring. Also, the spring 19 is not limited to a coil spring, but may be a leaf spring.

[0055] The pressing mechanism 12 may be modified as appropriate to have another structure, such as a structure in which the pusher 20 is omitted or a structure in which a cap is provided. The metal plate 2 does not necessarily have to be made entirely of metal, but may be, for example, a member in which a metal layer is formed on the surface of resin.

[0056] The sensor unit 10 is not limited to a structure in which it is in close contact with the metal plate 2 through the holes in the damping material 34 and the holder 39. For example, it may be a structure in which it extends radially outward from the damping material 34 and protrudes from the periphery of the damping material 34, and the protruding portion is in close contact with the metal plate 2.

[0057] The communication signal used in the sensor assembly 1 is not limited to ultrasonic waves, and other signals such as radio waves may also be used. The sensor assembly 1 may be used in equipment or devices other than vehicles.

[0058] While the present disclosure has been described with reference to the embodiments, it is understood that the present disclosure is not limited to those embodiments or structures. The present disclosure also encompasses various modifications and equivalent modifications. In addition, various combinations and forms, including only one element, more than one element, or less than one element, are also within the scope and spirit of the present disclosure. [Explanation of symbols]

[0059] 1...sensor assembly, 2...metal plate, 3...object, 7...design plate, 10...sensor unit, 11...bracket, 12...pressure mechanism, 34...vibration damping material, 35...opening hole, 39...holder, 41...holder hole, 42...positioning protrusion, 43...intervening member, 44...bracket support portion, 45...locking mechanism, 47...recess, 48...protrusion, Sa...transmitted wave, Sb...reflected wave.

Claims

1. A sensor assembly that transmits a transmission wave from a sensor unit disposed in close contact with a rear surface of a metal plate to a surrounding area through the metal plate, and detects an object based on a reflected wave of the transmission wave reflected by the object, a bracket that houses the sensor unit; a vibration-damping material attached to a rear surface of the metal plate to suppress transmission of vibrations in a direction from the metal plate toward the sensor unit; a holder that is positioned and attached to the vibration-damping material and to which the bracket is attached.

2. The sensor assembly according to claim 1 , further comprising an interposition member disposed between the metal plate and the holder.

3. the damping material has an opening that allows the sensor unit to reach the metal plate; the holder has a holder hole that is positioned coaxially with the opening hole when attached to the vibration-damping material, The sensor assembly according to claim 1 , wherein when the bracket is attached to the holder, the sensor unit is exposed to the metal plate through the opening hole and the holder hole, thereby being in close contact with the metal plate.

4. 4. The sensor assembly according to claim 3, wherein the holder has a positioning protrusion that protrudes from at least a portion of the periphery of the holder hole and is fitted into the opening hole of the vibration damping material.

5. The sensor assembly according to claim 1 , wherein the holder has a bracket support portion disposed through the vibration-damping material to support the bracket.

6. 6. The sensor assembly of claim 5, wherein a locking mechanism is provided between the bracket and the bracket support portion, which fixes the bracket to the holder by engaging a protrusion formed on one of the bracket and the bracket support portion with a recess formed on the other of the bracket and the bracket support portion.

7. 2. The sensor assembly according to claim 1, further comprising a pressing mechanism that presses the sensor unit from a rear surface to bring the sensor unit into close contact with the metal plate when the sensor unit and the holder are assembled together.

8. The sensor assembly according to claim 1 , wherein the metal plate is a flat design plate that is visible from the outside as a design.

Images