JP7851782B2 - Mounting unit and sensor unit - Google Patents

Description

This disclosure relates to a mounting unit and a sensor unit.

Patent Document 1 describes a structure for mounting an ultrasonic sensor on a vehicle. In this structure, the ultrasonic sensor is mounted on a front bumper made of a metal plate. The front bumper is provided with mounting holes for attaching the ultrasonic sensor. A bezel is inserted through the mounting holes, and in this state, a retainer is sandwiched between the bezel and the front bumper. The ultrasonic sensor is attached to the front bumper via the bezel and retainer. The retainer has an elastic portion, which is a cantilevered leaf spring portion extending from the retainer body, and this elastic portion abuts against the back surface of the front bumper.

Japanese Patent Publication No. 2021-173560

Incidentally, sonar sensors generate ultrasonic waves by vibrating their microphone surface and measure the distance to obstacles by receiving the ultrasonic waves that bounce back after hitting an obstacle. By mounting multiple sonar sensors, the exact location of obstacles can be determined. Sonar sensors have a fixed ultrasonic wave irradiation range, and to ensure detection performance according to the design specifications, it is necessary to hold the sonar sensor in the optimal mounting position. However, holding a sonar sensor alone is difficult, so it is conceivable to attach a dedicated sensor holding component (retainer) to the mounting component, such as a bumper, and hold the sonar sensor through this component.

On the other hand, mounting sonar sensors on metal parts may lead to false detections and compromise performance. This is partly because vibrations from the side of the sonar sensor's microphone are transmitted to metal parts that are less susceptible to vibration damping, causing reflections that can be received by sensors adjacent to the ultrasonic sensor. In particular, the vibration transmission speed of metal parts is approximately 15 times faster than that of air. Therefore, the vibrations of metal parts are detected before obstacles are detected by air vibrations, leading to a significant increase in false detections.

In the structure described in Patent Document 1, the elastic portion extending from the retainer body is in contact with the front bumper, which is made of a metal plate. Therefore, there is a risk that vibrations may be transmitted to the metal front bumper via the retainer. Thus, further consideration is needed to suppress false detections and ensure detection performance.

Therefore, this disclosure aims to provide a mounting unit and a sensor unit capable of ensuring detection performance.

The mounting unit according to this disclosure is a mounting unit for mounting a sonar sensor on a plate-shaped metal part of a vehicle, comprising: a resin plate to which the sonar sensor is attached and which is fixed to the metal part; and a rubber cushion provided on the resin plate. The metal part has a first opening formed therein. The resin plate has a main body portion inserted into the first opening of the metal part and a fixing portion for fixing the main body portion to the metal part. The main body portion includes a first surface to which the sonar sensor is attached, a second surface opposite to the first surface which includes a facing region that faces the metal part when the main body portion is inserted into the first opening of the metal part, and a second opening that exposes the microphone surface of the sonar sensor attached to the first surface to the second surface. The rubber cushion is provided on the second surface so as to be interposed between the facing region and the metal part when the unit is inserted.

This mounting unit includes a resin plate fixed to a metal component. The sonar sensor is attached to the first surface of the main body of the resin plate, and the microphone surface of the sonar sensor is exposed to the second surface opposite the first surface through a second opening in the main body. Therefore, when the sonar sensor is attached to the resin plate and the main body of the resin plate is inserted into the first opening of the metal component, the microphone surface of the sonar sensor is exposed to the outside of the metal component through the first and second openings. This enables the transmission of ultrasonic waves to the outside of the metal component and the reception of ultrasonic waves from the outside of the metal component. In particular, in this mounting unit, when the main body of the resin plate is inserted into the first opening of the metal component, a rubber cushion is interposed between the opposing region of the second surface of the resin plate and the metal component. In other words, with this mounting unit, at least a resin plate with excellent vibration damping properties and a rubber cushion are interposed between the sonar sensor and the metal component. Therefore, false detections due to vibrations from the sonar sensor being transmitted to the metal component are suppressed, and detection performance is ensured. In other words, this mounting unit makes it possible to suitably mount sonar sensors on metal parts where mounting sonar sensors was previously difficult.

Here, if water accumulates between the sonar sensor and the metal component, the vibration transmission speed increases, raising the risk of false detection. Therefore, to suppress false detections and ensure detection performance, it is desirable to create an environment where moisture is less likely to penetrate between the sonar sensor and the metal component.

Therefore, in the mounting unit according to this disclosure, the opposing region has an annular shape, and the rubber cushion is formed in a frame shape and provided around the entire circumference of the opposing region, filling the space between the opposing region and the metal component when inserted. In this case, the intrusion of moisture between the resin plate and the metal component is suppressed. Thus, false detections are further suppressed, and detection performance is reliably ensured.

In the mounting unit according to this disclosure, the opposing region includes a first region facing the inner surface of the first opening in the inserted state, and a second region extending from the first region in a direction intersecting the first region, facing the plate surface of the metal part on the outside of the first opening in the inserted state. The rubber cushion may include a cylindrical portion inserted into the first opening together with the main body in the inserted state and interposed between the first region and the inner surface, and a flange portion provided on the cylindrical portion so as to protrude to the outside of the cylindrical portion and interposed between the second region and the plate surface in the inserted state. In this case, the rubber cushion described above can be reliably constructed.

In the mounting unit according to this disclosure, the flange portion may include a protrusion that extends outward from the second region. In this case, the flange portion of the rubber cushion protrudes from the opposing region of the second surface of the resin plate. Therefore, water retention between the opposing region of the resin plate and the metal component is reliably suppressed.

The sensor unit according to this disclosure comprises one of the above-described mounting units, a retainer attached to the first surface, and a sonar sensor held by the retainer and attached to the first surface via the retainer, with its microphone surface exposed to the second surface through a second opening. This sensor unit includes the above-described mounting unit. Therefore, false detections caused by vibrations from the sonar sensor being transmitted to the metal part are suppressed, and detection performance is ensured. Furthermore, it becomes possible to suitably mount the sonar sensor on the metal part.

The sensor unit according to this disclosure may include a cushioning ring attached to the side of the microphone so as to surround the side of the microphone connected to the microphone surface of the sonar sensor. In this case, the cushioning ring dampens vibrations emanating from the side of the microphone, thereby suppressing the propagation of such vibrations to other parts via the retainer. Therefore, detection performance can be reliably ensured, and the sonar sensor can be more suitably mounted on metal parts.

This disclosure provides an onboard unit and a sensor unit capable of ensuring detection performance.

Figure 1 is a perspective view showing how the mounting unit according to this embodiment is mounted on a metal component. Figure 2 is an exploded perspective view of the sensor unit equipped with the mounting unit shown in Figure 1. Figure 3 is a cross-sectional view showing the sensor unit shown in Figure 2 mounted on a metal component. Figure 4 is a perspective view showing the various parts of the mounting unit shown in Figure 1.

The following description of one embodiment will be given with reference to the drawings. In the following description of the drawings, the same or equivalent elements will be denoted by the same reference numerals, and redundant explanations may be omitted. Furthermore, each figure may show a Cartesian coordinate system defined by a first axis indicating the first direction D1, a second axis indicating the second direction D2, and a third axis indicating the third direction D3. For example, the first direction D1 and the second direction D2 are two intersecting horizontal directions, and the third direction D3 is a vertical direction intersecting the first direction D1 and the second direction D2.

Figure 1 is a perspective view showing the mounting unit according to this embodiment mounted on a metal component. Figure 2 is an exploded perspective view of the sensor unit equipped with the mounting unit shown in Figure 1. Figure 3 is a cross-sectional view of the sensor unit shown in Figure 2 mounted on a metal component. Figure 4 is a perspective view showing various parts of the mounting unit shown in Figure 1.

As shown in Figures 1-4, the sensor unit 1 is equipped with a sonar sensor 50 that transmits and receives ultrasonic waves, and is mounted on a plate-shaped metal part A. The metal part A is, for example, a rear bumper of a vehicle such as a truck, and is a sheet metal part. The metal part A has multiple openings (first openings) Ah formed through it (only one is shown in the figure). The multiple openings Ah are arranged spaced apart from each other along the second direction D2.

A sensor unit 1 (i.e., a sonar sensor 50) is attached to each of the multiple openings Ah on the metal part A. Therefore, multiple sensor units 1 are mounted on the metal part A, arranged spaced apart from each other along the second direction D2 (only one is shown in the illustration). This allows the vehicle to detect obstacles and measure the distance to and position of the obstacles. Here, we will describe one of the multiple sensor units 1.

The sensor unit 1 comprises a mounting unit 30, a retainer 40, a sonar sensor 50, and a cushioning ring 54. The sonar sensor 50 includes a cylindrical sensor body 51 and a housing 52 provided at the base end of the sensor body 51. The sensor body 51 has a microphone surface 53 that emits ultrasonic waves at the end opposite the housing 52. The sensor body 51 also has a microphone side (not shown) connected to the microphone surface 53 around its periphery. The cushioning ring 54 is attached to the microphone side so as to surround it.

The mounting unit 30 includes a resin plate 10 and a rubber cushion 20. The resin plate 10 includes a main body portion 11 and a fixing portion 12. The main body portion 11 includes a flat bottom wall portion 13, a rectangular frame-shaped inner wall portion 14 erected on the outer edge of the bottom wall portion 13, a rectangular frame-shaped outer wall portion 15 provided outside the inner wall portion 14 and larger than the inner wall portion 14, and a connecting portion 16 connecting the inner wall portion 14 and the outer wall portion 15.

As a result, steps are formed in the main body 11 between the bottom wall 13 and the inner wall 14, and between the inner wall 14 and the outer wall 15, so that the bottom wall 13 protrudes furthest outward (recesses inward). A circular opening (second opening) 13h is formed in the bottom wall 13, penetrating it. A pair of fixing parts 12 are provided so as to protrude outward from the outer wall 15, in the portion of the outer wall 15 facing the opening 13h in the second direction D2. A circular through-hole 12h (reference hole) is formed in one of the pair of fixing parts 12, and an elongated through-hole 12i (sub-reference hole) is formed in the other of the pair of fixing parts 12. The circular through-hole 12h is formed in a circular shape when viewed from the first direction D1, and the elongated through-hole 12i is formed so as to be relatively longer in the second direction D2 than in the third direction D3 when viewed from the first direction D1.

The main body 11 includes an inner surface (first surface) 11s and an outer surface (second surface) 11r opposite to the inner surface 11s. The inner surface 11s is the surface to which the sonar sensor 50 is attached (via the retainer 40). The inner surface 11s is composed of the bottom wall 13, the inner wall 14, the outer wall 15, and the inner surface of the connecting portion 16. The outer surface 11r is composed of the bottom wall 13, the inner wall 14, the outer wall 15, and the outer surface of the connecting portion 16. The opening 13h allows the sensor body 51 of the sonar sensor 50 to be inserted when the sonar sensor 50 is attached to the inner surface 11s, exposing the microphone surface 53 of the sonar sensor 50 to the outer surface 11r.

On the inner surface 11s, in the portion corresponding to the inner surface of the bottom wall 13, a group of reference lines LG is provided on both sides of the opening 13h in the third direction D3. The group of reference lines LG provides a guideline for the mounting position (orientation) when attaching the sonar sensor 50 to the inner surface 11s.

Each of the reference line groups LG includes a reference line L1 extending linearly along the second direction D2, and a pair of reference lines L2 that intersect reference line L1 at its center and extend linearly. Each of the pair of reference lines L2 is inclined with respect to reference line L1, as if rotated by a predetermined angle in both the forward and reverse directions around the center of reference line L1. Within each pair of reference line groups LG, the reference lines L1 and the reference lines L2 inclined in the same direction are approximately parallel to each other.

Therefore, when attaching the sonar sensor 50 to the inner surface 11s via the retainer 40, the mounting position (orientation) of the sonar sensor 50 can be defined by aligning the outer edge of the retainer 40 in the third direction D3 with a pair of substantially parallel reference lines L1. Furthermore, when attaching the sonar sensor 50 to the inner surface 11s via the retainer 40, a certain level of mounting accuracy can be ensured by ensuring that the outer edge of the retainer 40 in the third direction D3 falls within the range between the pair of reference lines L2.

The resin plate 10 described above is fixed to the metal part A by fixing the fixing portion 12 to the fixing portion A1 provided on the plate surface As of the metal part A. More specifically, the metal part A is provided with a pair of hat-shaped bracket fixing portions A1 (for example, by welding), and the fixing portion 12 and fixing portion A1 are overlapped so that the round through-hole 12h of the fixing portion 12 aligns with the hole A1h of one of the fixing portions A1.

In this state, the fastening members (e.g., tapping screws) A3, which are inserted through the round through-hole 12h and the elongated through-hole 12i, are fastened (e.g., screwed) to the fastened members (e.g., grommets) A2, which are inserted through the holes A1h of the pair of fixing parts A1. This fastens the fixing part 12 to the fixing part A1, and the main body 11 and the resin plate 10 are fixed to the metal part A. At this time, a portion of the resin plate 10 is inserted into the opening Ah of the metal part A. Here, the bottom wall portion 13 of the main body 11 is inserted into the opening Ah and positioned within the opening Ah. Hereafter, this state in which the main body 11 is inserted into the opening Ah will simply be referred to as the "inserted state."

The outer surface 11r of the main body 11 includes a facing region 17 that faces the metal part A in the inserted state. The facing region 17 includes a first region 17a that faces the inner surface Ahs of the opening Ah of the metal part A in the inserted state, and a second region 17b that extends from the first region 17a in a direction intersecting the first region 17a and faces the plate surface As of the metal part A outside the opening Ah in the inserted state. The first region 17a is a rectangular cylindrical region extending along the first direction D1, and the second region 17b is a rectangular annular region extending along the second direction D2 and the third direction D3.

The rubber cushion 20 is provided on the outer surface 11r of the main body 11 so as to be interposed between the opposing region 17 and the metal part A when inserted. The rubber cushion 20 is adhered to the outer surface 11r, for example, by double-sided tape. The rubber cushion 20 is formed in a rectangular frame shape and is provided around the entire circumference of the opposing region 17. More specifically, the rubber cushion 20 includes a rectangular cylindrical portion 21 and a rectangular annular flange portion 22. The rubber cushion 20 can be adhered to the outer surface 11r at the flange portion 22.

The cylindrical portion 21 is positioned to surround the bottom wall portion 13 when the rubber cushion 20 is provided on the outer surface 11r of the main body portion 11 (in other words, the bottom wall portion 13 is positioned inside the cylindrical portion 21). The flange portion 22 is provided on the cylindrical portion 21 so as to protrude from its end to the outside of the cylindrical portion 21. The rubber cushion 20 is formed in an L-shape in cross-section by the cylindrical portion 21 and the flange portion 22.

The cylindrical portion 21, in the inserted state, is inserted into the opening Ah of the metal part A together with the main body portion 11 (bottom wall portion 13) of the resin plate 10, and is interposed between the first region 17a of the opposing region 17 and the inner surface Ahs of the opening Ah. The flange portion 22, in the inserted state, is interposed between the second region 17b of the opposing region 17 and the plate surface As of the metal part A. In particular, the flange portion 22 includes a protruding portion 23 that extends around the entire circumference of the second region 17b and protrudes outward from the second region 17b. When the resin plate 10 is fixed to the metal part A, the rubber cushion 20 is pressed between the resin plate 10 and the metal part A and elastically deformed. As a result, the rubber cushion 20 contacts both the metal part A and the resin plate 10 (main body portion 11) and fills the space between them almost completely without gaps.

The retainer 40 includes a cylindrical sensor holding portion 41, a flat plate-shaped mounting portion 42 provided at one end of the sensor holding portion 41 and extending outward from the sensor holding portion 41, and an engaging portion 43 provided at the other end of the sensor holding portion 41. The sensor body 51 of the sonar sensor 50 is inserted into the sensor holding portion 41. The engaging portion 43 engages with an engaging portion 55 provided on the housing 52 of the sonar sensor 50 when the sensor body 51 is inserted into the sensor holding portion 41.

This allows the retainer 40 to hold the sonar sensor 50. The retainer 40 is attached to the resin plate 10 by bonding (for example, by double-sided tape) its mounting portion 42 to the inner surface 11s of the main body portion 11 of the resin plate 10. In other words, the sonar sensor 50 is held by the retainer 40 and attached to the inner surface 11s of the resin plate 10 via the retainer 40, with the microphone surface 53 exposed to the outer surface 11r through the opening 13h of the resin plate 10.

For example, the retainer 40 may be made from a resin such as ABS. Also, for example, the resin plate 10 may be made from PP material, which easily converts vibration energy into thermal energy. Furthermore, for example, the rubber cushion 20 may be made from a material such as EPDM. The cushion ring 54 may be made from a material such as silicone.

As described above, the mounting unit 30 according to this embodiment includes a resin plate 10 fixed to the metal part A. The sonar sensor 50 is attached to the inner surface 11s of the main body portion 11 of the resin plate 10, and the microphone surface 53 of the sonar sensor 50 is exposed to the outer surface 11r opposite the inner surface 11s through the opening 13h of the main body portion 11. Therefore, by attaching the sonar sensor 50 to the resin plate 10 and inserting the main body portion 11 of the resin plate 10 into the opening Ah of the metal part A, the microphone surface 53 of the sonar sensor 50 is exposed to the outside of the metal part A through the openings 13h and Ah. This enables the transmission of ultrasonic waves to the outside of the metal part A and the reception of ultrasonic waves from the outside of the metal part A.

In particular, in the mounting unit 30, when the main body 11 of the resin plate 10 is inserted into the opening Ah of the metal part A, a rubber cushion 20 is interposed between the opposing region 17 of the outer surface 11r of the resin plate 10 and the metal part A. In other words, with the mounting unit 30, at least the resin plate 10, which has excellent vibration damping properties, and the rubber cushion 20 are interposed between the sonar sensor 50 and the metal part A. Therefore, false detections caused by vibrations from the sonar sensor 50 being transmitted to the metal part A are suppressed, and detection performance is ensured. In other words, with the mounting unit 30, it becomes possible to suitably mount the sonar sensor 50 on a metal part A where mounting the sonar sensor 50 was previously difficult.

Furthermore, in the mounting unit 30, the opposing region 17 has an annular shape, and the rubber cushion 20 is formed in a frame shape and is provided around the entire circumference of the opposing region 17. The rubber cushion 20 fills the space between the opposing region 17 and the metal part A when inserted. Therefore, the intrusion of moisture between the resin plate 10 and the metal part A is suppressed. Thus, false detections are further suppressed, and detection performance is reliably ensured.

Furthermore, in the mounting unit 30, the opposing region 17 includes a first region 17a that faces the inner surface Ahs of the opening Ah in the inserted state, and a second region 17b that extends from the first region 17a in a direction intersecting the first region 17a and faces the plate surface As of the metal part A on the outside of the opening Ah in the inserted state. The rubber cushion 20 includes a cylindrical portion 21 that is inserted into the opening Ah together with the main body 11 in the inserted state and interposed between the first region 17a and the inner surface Ahs, and a flange portion 22 provided on the cylindrical portion 21 so as to protrude to the outside of the cylindrical portion 21 and interposed between the second region 17b and the plate surface As in the inserted state. This ensures that the rubber cushion 20 described above can be reliably constructed.

Furthermore, in the mounting unit 30, the flange portion 22 includes a protruding portion 23 that extends outward from the second region 17b. Therefore, the flange portion 22 of the rubber cushion 20 protrudes from the opposing region 17 of the outer surface 11r of the resin plate 10. Consequently, water retention between the opposing region 17 of the resin plate 10 and the metal component A is reliably suppressed.

Furthermore, the sensor unit 1 according to this embodiment comprises the mounting unit 30 described above, a retainer 40 attached to the inner surface 11s, and a sonar sensor 50 that is held by the retainer 40 and attached to the inner surface 11s via the retainer 40, with its microphone surface 53 exposed to the outer surface 11r through the opening 13h. The sensor unit 1 includes the mounting unit 30 described above. Therefore, false detections caused by vibrations from the sonar sensor 50 being transmitted to the metal part A are suppressed, and detection performance is ensured. In addition, the sonar sensor 50 can be suitably mounted on the metal part A.

Furthermore, the sensor unit 1 includes a cushioning ring 54 mounted on the side of the microphone, surrounding the side of the microphone connected to the microphone surface 53 of the sonar sensor 50. Therefore, the cushioning ring 54 attenuates vibrations emanating from the side of the microphone, thereby suppressing the propagation of these vibrations to other components via the retainer 40. This ensures reliable detection performance and allows for a more suitable mounting of the sonar sensor 50 on metal components.

The above embodiments describe one form of the mounting unit and sensor unit according to this disclosure. Therefore, the mounting unit and sensor unit according to this disclosure may be modified in any way as described above.

For example, the manner in which the metal part A and the resin plate 10 are fixed, and the manner in which the rubber cushion 20 and retainer 40 are attached to the resin plate 10, are not limited to those described above, but can be any manner. As one example, the rubber cushion 20 and retainer 40 may be fixed to the resin plate 10 by fitting.

Furthermore, in the above embodiment, the flange portion 22 of the rubber cushion 20 had a protruding portion 23 that projected outward from the area where the second region 17b of the opposing region 17 of the resin plate 10 and the metal part A faced each other. However, from the viewpoint of filling the space between the second region 17b of the opposing region 17 of the resin plate 10 and the metal part A, the protruding portion 23 is not essential. In this case, for example, the end of the flange portion 22 and the end of the second region 17b may be configured to be flush. Moreover, if the possibility of moisture intrusion is low, the end of the flange portion 22 may be recessed relative to the end of the second region 17b.

1…Sensor unit, 10…Resin plate, 11…Main body, 11s…Inner surface (first surface), 11r…Outer surface (second surface), 12…Fixing part, 13h…Opening (second opening), 20…Rubber cushion, 21…Cylindrical part, 22…Flange part, 23…Protruding part, 30…Mounting unit, 40…Retainer, 50…Sonar sensor, 54…Cushion ring, A…Metal part, As…Plate surface, Ah…Opening (first opening), Ahs…Inner surface.

Claims (3)

A mounting unit for attaching a sonar sensor to a plate-shaped metal part of a vehicle,
A resin plate to which the sonar sensor is attached and which is fixed to the metal part,
A rubber cushion provided on the aforementioned resin plate,
Equipped with,
The aforementioned metal part has a first opening formed therein.
The aforementioned resin plate is
The main body portion is inserted into the first opening of the metal part,
A fixing part for fixing the main body to the metal part,
It has,
The main body is,
The first surface on which the sonar sensor is attached,
A second surface which is the surface opposite to the first surface and includes a facing region that faces the metal part when the main body is inserted into the first opening of the metal part,
A second opening that exposes the microphone surface of the sonar sensor mounted on the first surface to the second surface,
Includes,
The rubber cushion is provided on the second surface so as to be interposed between the opposing region and the metal component in the inserted state.
The opposing region has an annular shape ,
The rubber cushion is formed in a frame shape and is provided around the entire circumference of the opposing region, filling the space between the opposing region and the metal part in the inserted state.
The opposing region is,
In the insertion state, the first region facing the inner surface of the first opening,
A second region extending from the first region in a direction intersecting the first region, and in the inserted state, facing the plate surface of the metal part outside the first opening,
Includes,
The aforementioned rubber cushion is
In the aforementioned insertion state, a cylindrical portion is inserted into the first opening together with the main body and interposed between the first region and the inner surface,
A flange portion is provided on the cylindrical portion so as to protrude to the outside of the cylindrical portion, and is interposed between the second region and the plate surface in the inserted state,
Includes,
The flange portion includes a projection that protrudes outward from the second region.
The first surface is provided with a group of reference lines that provide a guideline for the mounting position when attaching the sonar sensor to the first surface.
The installed unit. The mounting unit according to claim 1 ,
A retainer attached to the first surface,
The sonar sensor is held by the retainer and attached to the first surface via the retainer, with the microphone surface exposed to the second surface through the second opening,
A sensor unit equipped with the following features. The sonar sensor is equipped with a cushioning ring attached to the side of the microphone so as to surround the side of the microphone connected to the microphone surface of the sonar sensor.
The sensor unit according to claim 2 .