Ultrasonic server device and vehicle

Abstract

To provide an ultrasonic sensor device having a wide horizontal directivity and an extremely narrow vertical directivity.SOLUTION: An ultrasonic sensor is provided with a bottomed cylindrical case. The case includes a first thin wall section, a first thick wall section having a first protrusion, a second thin wall section, and a second thick wall section having a second protrusion. The first and second thin wall sections face each other. The first and second thick wall sections face each other. All or a part of the first and second protrusions is curved in line symmetry with respect to an X axis. DX is equal to or longer than 20.5% of B and DY is equal to or longer than 34.1% of B, DX representing the lengths of the first and second protrusions on the X axis, DY representing the lengths on a Y axis at midpoints of the lengths of the first and second protrusions on the X axis, and B representing the length of opening from the first thin wall section to the second thin wall section.SELECTED DRAWING: Figure 5A

Description

Technical Field

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[0001] The present disclosure relates to an ultrasonic sensor device that transmits or receives ultrasonic waves, or both, and a vehicle.

Background Art

[0002] Conventionally, for example, an ultrasonic sensor attached to the rear end of a vehicle to detect obstacles behind the vehicle is known (for example, Patent Document 1).

[0003] The ultrasonic sensor in Patent Document 1 includes a bottomed cylindrical case, a piezoelectric element, a pair of lead wires, and a filler. The piezoelectric element is installed on the inner bottom surface of the case, and the filler seals the case. The pair of lead wires supplies power to the piezoelectric element. The inner diameter of the bottomed cylindrical case has two facing protrusions, and each protrusion has a tip.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The problem to be solved by the present disclosure is to provide an ultrasonic sensor device having a wide directivity in the horizontal direction and an extremely narrow directivity in the vertical direction.

Means for Solving the Problems

[0006] An ultrasonic sensor device according to one aspect of the present disclosure comprises a bottomed cylindrical case. The case has a first thin wall portion formed along the inner wall surface of the case, a first thick wall portion having a first projection protruding from the inner wall surface of the case toward the internal space of the case, a second thin wall portion formed along the inner wall surface of the case, and a second thick wall portion having a second projection protruding from the inner wall surface of the case toward the internal space of the case. In a cross-section parallel to the inner bottom surface of the case, the first thin wall portion and the second thin wall portion face each other, and the first thick wall portion and the second thick wall portion face each other. The X-axis is defined as the direction passing through the center of the case and for which wide-angle directivity is desired in the directivity characteristics of the ultrasonic sensor device. The Y-axis is defined as the direction passing through the center of the case and for which narrow-angle directivity is desired in the directivity characteristics of the ultrasonic sensor device. All or part of the first projection and the second projection have a curved shape that is symmetric with respect to the X-axis. Let DX be the length of the first protrusion and the second protrusion along the X-axis, and DY be the length of the Y-axis at the midpoint of the lengths of the first and second protrusions along the X-axis. In the internal space of the case, when the opening length from the first thin wall to the second thin wall is B, DX has a length of 20.5% or more of B, and DY has a length of 34.1% or more of B. [Brief explanation of the drawing]

[0007] [Figure 1A] This is a perspective view of the ultrasonic device in this embodiment. [Figure 1B] This is a cross-sectional view of the ultrasonic device in this embodiment. [Figure 1C] This is a cross-sectional view of a cross-section perpendicular to the cross-section in Figure 1B in this embodiment. [Figure 2A] This is a top view of the case of the ultrasonic device in this embodiment. [Figure 2B] This is a side view of the case of the ultrasonic device in this embodiment. [Figure 2C] This is a front view of the case of the ultrasonic device in this embodiment. [Figure 2D] This is a perspective view of the case of the ultrasonic device in this embodiment. [Figure 3]This is a cross-sectional view of the case of the ultrasonic device in this embodiment. [Figure 4A] This is a block diagram of the ultrasonic sensor in this embodiment. [Figure 4B] This is a block diagram of another ultrasonic sensor of this embodiment. [Figure 4C] This is a schematic diagram of a vehicle equipped with an ultrasonic sensor according to this embodiment. [Figure 5A] This is a perspective view of the ultrasonic device in a modified example 1 of this embodiment. [Figure 5B] This is a cross-sectional view of an ultrasonic device in a modified example 1 of this embodiment. [Figure 6A] This is a perspective view of the ultrasonic device in a modified example 2 of this embodiment. [Figure 6B] This is a cross-sectional view of an ultrasonic device in a modified example 2 of this embodiment. [Modes for carrying out the invention]

[0008] The embodiments of this disclosure will be described below with reference to the drawings.

[0009] (Embodiment) Ideally, ultrasonic sensors should have a wide horizontal transmission and reception range for ultrasonic waves, allowing them to detect obstacles far from the vehicle, while also having a narrow vertical directivity to avoid detecting reflections from the ground or ceiling.

[0010] However, with conventional ultrasonic sensors, increasing the ultrasonic output to detect obstacles at long distances from the rear of a vehicle also increases the vertical detection range, leading to the detection of reflections from the ground and ceiling. There is a need for an ultrasonic device that improves upon this issue, possessing a wide horizontal directivity and an extremely narrow vertical directivity.

[0011] In the past, in such an ultrasonic device, for example, when the horizontal half-value angle is 63 degrees or more, it was desirable that the vertical half-value angle be 35 degrees or less, and when the horizontal half-value angle is 80 degrees or more, the vertical half-value angle be 41 degrees or less. That is, it was required to achieve a flatness ratio (horizontal half-value angle ÷ vertical half-value angle) of 2 or more.

[0012] However, in recent years, there has been an increasing number of cases where further improvement in the flatness ratio is required. For example, there are many cases where a flatness ratio of 2.5 or more and a vertical half-value angle of 35 degrees or less are required. Thus, there is a need to provide an ultrasonic device that can achieve a wider directivity in the horizontal direction and a narrower directivity in the vertical direction.

[0013] FIG. 1A is a perspective view of an ultrasonic device 11 in an embodiment. FIG. 1B is a cross-sectional view of the ultrasonic device 1 for the embodiment. FIG. 1C is a cross-sectional view taken perpendicular to the cross-section of FIG. 1B in the embodiment. In FIG. 1A, the dashed line is a hidden line indicating a portion that is not visible.

[0014] The ultrasonic device 11 of the present disclosure includes a bottomed cylindrical case 12, a piezoelectric element 13, a lead wire 14, and a filler 15. The piezoelectric element 13 is installed on the inner bottom surface of the case 12. The lead wire 14 is connected to the piezoelectric element 13. The filler 15 seals the case 12.

[0015] The case 12 has a first thin-wall portion 21A and a first thick-wall portion 22A. The first thin-wall portion 21A is formed along the inner wall surface of the case 12. The first thick-wall portion 22A has a first protruding portion 24A that protrudes from the inner wall surface of the case 12 toward the internal space of the case 12.

[0016] Case 12 has a bottomed cylindrical shape and has a bottom portion 16 and a cylindrical portion 17. Case 12 is made of a metal such as aluminum. The bottom portion 16 is a vibrating surface that emits ultrasonic waves and has an inner bottom surface 19 and an outer bottom surface 20. The cylindrical portion 17 has a pair of opposing thin wall portions 21 and a pair of opposing thick wall portions 22. That is, in Figure 1A, the cylindrical portion 17 has a first thin wall portion 21A and a second thin wall portion 21B. The first thin wall portion 21A and the second thin wall portion 21B are formed along the inner wall surface of Case 12.

[0017] Furthermore, the cylindrical portion 17 has a first thick wall portion 22A and a second thick wall portion 22B. The first thick wall portion 22A has a first projection 24A that protrudes from the inner wall surface of the case 12 toward the internal space of the case 12. The second thick wall portion 22B has a second projection 24B that protrudes from the inner wall surface of the case 12 toward the internal space of the case 12.

[0018] The outer shape of the first projection 24A includes a first ellipse 25A with its center point 28A, and has a shape in which a first tangent line 26A-1 that contacts the ellipse 25A at a point 27A-1 and a second tangent line 26A-2 that contacts the first ellipse 25A at a point 27A-2 spread outwards toward the outer circumference.

[0019] The outer shape of the second projection 24B includes a second ellipse 25B with its center point 28B, and has a shape in which the first tangent line 26B-1, which is tangent to the second ellipse 25B at point 27B-1, and the second tangent line 26B-2, which is tangent to the second ellipse 25B at point 27B-2, widen toward the outer circumference.

[0020] Here, the first thin-walled section 21A and the second thin-walled section 21B are collectively referred to as the thin-walled section 21. The first thick-walled section 22A and the second thick-walled section 22B are collectively referred to as the thick-walled section 22. The first protrusion 24A and the second protrusion 24B are collectively referred to as the protrusion 24. The first ellipse 25A and the second ellipse 25B are collectively referred to as the ellipse 25. The center point 28A of the first ellipse and the center point 28B of the second ellipse are collectively referred to as the center point 28 of the ellipse. The first tangent 26A-1 and the second tangent 26A-2 of the first ellipse 25A and the first tangent 26B-1 and the second tangent 26B-2 of the second ellipse 25B are collectively referred to as the tangent 26.

[0021] The thin-walled section 21 is a part with a relatively thin wall thickness, and has a substantially arc shape with a substantially constant wall thickness. Here, it is desirable that the thickness of the thin-walled section 21 be within a range of ±10% or less of the average thickness of the thin-walled section 21.

[0022] The piezoelectric element 13 is an ultrasonic vibration source fixed to the inner bottom surface 19 of the case 12, and has a piezoelectric body (not shown) and electrodes (not shown) provided on both sides thereof. A pair of lead wires 14 are made of conductors. Electrodes (not shown) are formed on both sides of the piezoelectric element 13. At least one of the lead wires 14 is connected to one electrode of the piezoelectric element 13. Power is supplied to the piezoelectric element 13 by the pair of lead wires 14.

[0023] The filler 15 is made of a resin material such as foamed silicone resin, and seals the piezoelectric element 13 inside the case 12.

[0024] Next, the structure of case 12 will be explained using Figures 2A to 2D and Figure 3. Figure 2A is a top view of case 12 of the ultrasonic device 11 in the embodiment. Figure 2B is a side view of case 12 of the ultrasonic device 11 in the embodiment.

[0025] Figure 2C is a front view of the case 12 of the ultrasonic device 11 in the embodiment. Figure 2D is a perspective view of the case 12 of the ultrasonic device 11 in the embodiment. Figure 3 is a cross-sectional view of the case 12 of the ultrasonic device 11 in the embodiment. Figure 3 substantially coincides with a cross-sectional view of the cylindrical portion 17 of the case 12 when the case 12 is cut by a plane parallel to the inner bottom surface 19.

[0026] As shown in Figures 2A and 1C, case 12 has a center point 23. Also, as shown in Figures 1A, 2A to 2C, the X, Y, and Z directions are defined in the ultrasonic device 11.

[0027] In Figure 2A, the location where the piezoelectric element 13 is positioned on the inner bottom surface 19 of case 12 is indicated by a rectangular dashed line. The piezoelectric element 13 is positioned so that the center of the inner bottom surface 19 of case 12 and the center of the piezoelectric element 13 are approximately coincident.

[0028] As shown in Figure 3, the dimensions of the case 12 are expressed as follows: the outer diameter A of the cylindrical portion 17, the opening length B of the thin-walled portion 21, the minimum opening length C of the thick-walled portion 22, the wall thickness D of the thin-walled portion 21, the X-direction diameter DX of the ellipse of the thick-walled portion 22, the Y-direction diameter DY of the ellipse of the thick-walled portion 22, and the X-direction length LC from the point of contact 27 where the ellipse 25 and the tangent line 26 touch to the ellipse's center line.

[0029] Figure 4A is a block diagram of the ultrasonic sensor 30 of this embodiment. Figure 4B is a block diagram of another ultrasonic sensor 30 of this embodiment. The ultrasonic sensor 30 comprises an ultrasonic device 11, a transmitting circuit 71, and a housing case 73. The ultrasonic device 11 is used as an ultrasonic transducer. The transmitting circuit 71 drives the ultrasonic device 11 and generates ultrasonic waves. The housing case 73 holds the ultrasonic device 11 and the transmitting circuit 71.

[0030] Here, as shown in Figure 4B, the housing case 73 may hold only the ultrasonic device 11. In other words, the housing case 73 only needs to be configured to hold at least the ultrasonic device 11.

[0031] Figure 4C is a schematic diagram of a vehicle 31 equipped with the ultrasonic sensor 30 of this embodiment. The ultrasonic sensor 30 emits ultrasonic waves and receives reflected ultrasonic waves to detect the presence of obstacles around the vehicle 31 and to detect the distance to the obstacles.

[0032] In Figure 1A, the ultrasonic device 11 is shown with the X and Y directions horizontal and the Z direction vertical. However, when installed on the vehicle 31, the ultrasonic device 11 is installed so that the Y direction is vertical (i.e., approximately vertical) and the X direction is horizontal (i.e., approximately horizontal).

[0033] In other words, the ultrasonic device 11 is installed so that its X and Z directions are approximately horizontal to the ground, and its Y direction is approximately vertical. Here, the Z direction is the direction in which the ultrasonic waves are transmitted or received.

[0034] By setting the direction of the ultrasonic device 11 and defining its shape in this way, it is possible to control the horizontal directivity while ensuring narrow directivity in the vertical direction.

[0035] Furthermore, the Z-direction may be angled slightly with respect to the horizontal direction of the vehicle 31. The Y-direction may also be angled slightly with respect to the vertical direction. In addition, the direction in which the ultrasonic waves are transmitted or received may be tilted slightly upward or downward from the horizontal.

[0036] Here, the directivity of the ultrasonic device 11 refers to the directivity of the ultrasonic receiving sensitivity when the ultrasonic device 11 is used to receive ultrasonic waves, and to the directivity of the ultrasonic radiation intensity when the ultrasonic device 11 is used to transmit ultrasonic waves.

[0037] Table 1 shows the evaluation results of the embodiments examined in this embodiment.

[0038] In Examples 1 to 50 shown in Table 1, the outer diameter A of the cylindrical portion 17 is 15.5 mm. The opening length B of the thin-walled portion 21 is 14.62 mm. The wall thickness D of the thin-walled portion 21 is 0.44 mm. The minimum opening length C of the thick-walled portion 22 is 6.6 mm. The diameter DX in the X direction of the ellipse 25 of the projection 24 of the thick-walled portion 22 is 2.0 mm or more and 8.0 mm or less, and the diameter in the Y direction is 3.0 mm or more and 9.0 mm or less. The tangent line 26 of the ellipse 25 forming the projection 24 has a point of contact 27 on the ellipse 25 at a distance (let's call this LC) of 0.8 mm in the X direction from the center line passing through the center point 28 of the ellipse 25.

[0039] However, if the contact point 27 cannot be located inside the thin wall portion 21 of the cylindrical portion 17, the shape of the protruding portion 24 shall be such that it is formed solely from the ellipse 25.

[0040] [Table 1]

[0041] Table 1 shows the dimensions of DX and DY for Case 12, and the vertical and horizontal beam angles and flatness (horizontal beam angle ÷ vertical beam angle) at half power (-6dB) relative to the maximum output when ultrasonic radiation is performed. In all cases from No. 1 to No. 50, the flatness exceeds 2.5, and examples with a flatness exceeding 2.5 are indicated as "G (Good)", while examples with a vertical beam angle of 35 degrees or less are indicated as "E (Excellent)". In other words, this indicates that the flatness is good simply because the ellipse 25 is included in the outer shape of the protrusion 24.

[0042] Table 2 is Table 1 rearranged with the DX and DY axes aligned.

[0043] [Table 2]

[0044] From (Table 2), it was found that the good directivity characteristic "E" depends on DX and DY. Good directivity angle characteristics can be obtained when DX is 3.0 mm or more, that is, it has a length of 20.5% or more of the opening length B of the thin wall portion 21, and DY is 5.0 mm or more, that is, it has a length of 34.1% or more of the opening length B of the thin wall portion 21.

[0045] Furthermore, when examining the distribution of "E", it was found that it is concentrated in the range of 2 mm, that is, 13.6% of the opening length B of the thin wall portion 21, mainly in the case where the relationship of a linear function where the slope of DY with respect to DX is 0.5 and the offset is 4.0 mm, that is, 27.3% of the opening length B of the thin wall portion 21, holds.

[0046] When expressed by a mathematical formula, a narrow-angle directivity in the vertical direction can be obtained when the relationship of DY - B×0.136 < (DX×0.5 + B×0.273) < DY + B×0.136 is satisfied.

[0047] (Modification Example 1) Note that the outer shapes of the first protruding portion 24A and the second protruding portion 24B are not limited to ellipses. As shown in FIGS. 5A and 5B, they may be parabolas. The first tangent line 26C-1 and the second tangent line 26C-2 of the parabola have a shape that spreads toward the outer periphery. Here, the outer shapes of the first protruding portion 24A and the second protruding portion 24B may be quadratic curves, the outer shape may be a circle, or the outer shapes of the first protruding portion 24A and the second protruding portion 24B may be hyperbolas. Also, at least one of the outer shapes of the first protruding portion 24A and the second protruding portion 24B may be a quadratic curve shape.

[0048] (Modification Example 2) Also, the tips of the first protruding portion 24A and the second protruding portion 24B may be flat. In FIGS. 6A and 6B, the protruding portion tip portions 40A and 40B of the protruding portions 24A and 24B are flat, and the protruding portion side wall portions 41A-1, 41A-2 and 41B-1, 41B-2 of the protruding portions 24A and 24B may be quadratic curves 25A and 25B, and cases of circles, ellipses, hyperbolas, or parabolas are considered. Also, there may be a case where the lead wire 14 is joined to the protruding portion 24A or the protruding portion 24B.

[0049] In this embodiment, the thickness of the first thick wall portion 22A and the second thick wall portion 22B does not change in the Z direction of the ultrasonic device 11, but the disclosure is not limited thereto. In the ultrasonic device of this disclosure, the thickness of the thick wall portion may change along the Z direction, or the thick wall may disappear along the Z direction. It is sufficient that at least a portion of the ultrasonic device in the Z direction forms a thick wall portion.

[0050] The ultrasonic device of this disclosure comprises a bottomed cylindrical case 12, a piezoelectric element 13, lead wires 14, and a filler material 15. The piezoelectric element 13 is installed on the inner bottom surface 19 of the case 12. The lead wires 14 are connected to the piezoelectric element 13. The filler material 15 seals the case 12.

[0051] Case 12 has a first thin wall portion 21A, a first thick wall portion 22A, a second thin wall portion 21B, and a second thick wall portion 22B. The first thin wall portion 21A and the second thin wall portion 21B are formed along the inner wall surface of case 12. The first thick wall portion 22A has a first projection 24A that protrudes from the inner wall surface of case 12 toward the internal space of case 12. The second thick wall portion 22B has a second projection 24B that protrudes from the inner wall surface of case 12 toward the internal space of case 12.

[0052] Furthermore, the first thick wall portion 22A has a first projection 24A that protrudes from the inner wall surface of the case 12 toward the internal space of the case 12, and the second thick wall portion 22B has a second projection 24B that protrudes from the inner wall surface of the case 12 toward the internal space of the case 12.

[0053] The outer shape of the first projection 24A includes the first ellipse 25A, and its first tangent 26A-1 and second tangent 26A-2 have a shape that widens toward the outer circumference. The outer shape of the second projection 24B includes the second ellipse 25B, and its first tangent 26B-1 and second tangent 26B-2 have a shape that widens toward the outer circumference.

[0054] Assume the direction for obtaining wide directivity is the X direction, and the direction for obtaining narrow directivity is the Y direction. Let the diameter in the X direction of ellipse 25A or ellipse 25B be DX, the diameter in the Y direction be DY, and the opening length of the thin-walled portion 21 be B. Then, DX has a length of 20.5% or more of B, and DY satisfies a length of 34.1% or more of B.

[0055] Furthermore, when DX and DY satisfy the relationship of DY - B×0.136 < (DX×0.5 + B×0.273) < DY + B×0.136, a narrower directivity in the Y direction can be obtained.

[0056] As described above, the ultrasonic device 11 of the present embodiment has a piezoelectric element 13 on the inner bottom surface 19 of the bottomed cylindrical case 12. And in a cross-section parallel to the inner bottom surface 19 of the case 12, the cylindrical portion 17 of the case 12 has a thin-walled portion 21 whose inner wall surface is a substantially arc shape centered on the center point 23 of the case 12, and a thick-walled portion 22 having a thickness thicker than that of the thin-walled portion 21 and whose inner wall surface protrudes toward the inner space of the case.

[0057] By including the ellipse 25 in the shape of the protruding portion 24, it becomes possible to design a directivity that exceeds the conventional directivity level. As a result, while ensuring a wide directivity in the X direction, an extremely narrow directivity can be realized in the Y direction. By equipping the vehicle 31 with the ultrasonic sensor 30 provided with the ultrasonic device 11 as an ultrasonic transducer and using it for detecting obstacles, the influence due to reflection from the road surface or reflection from the ceiling of a garage or the like can be reduced, and detection with a wide directivity in the horizontal direction becomes possible.

[0058] For example, obstacles behind the vehicle can be accurately detected. Further, when a narrower directivity in the Y direction is required, it is desirable that the diameter DX in the X direction of the ellipse 25 has a length of 20.5% or more of the opening length B of the thin-walled portion 21, and the diameter DY in the Y direction has a length of 34.1% or more of the opening length B of the thin-walled portion 21.

[0059] Also, when DX and DY satisfy the relationship of DY - B×0.136 < (DX×0.5 + B×0.273) < DY + B×0.136, a narrower directivity in the Y direction can be obtained.

[0060] In this embodiment, the thickness of the thin wall portion 21 is set to be approximately constant, but it is not necessary for it to be approximately constant. For example, the thickness of the thin wall portion 21 may be sloped. With the above configuration, the ultrasonic device and ultrasonic sensor of this disclosure have a wide directivity in the horizontal direction while having an extremely narrow directivity in the vertical direction. [Explanation of Symbols]

[0061] 11 Ultrasonic devices 12 cases 13 Piezoelectric element 14 Lead wires 15 Filler 16 Bottom 17 Cylinder part 19 Inner bottom surface 20 Outer bottom surface 21 Thin wall section 21A First thin wall section 21B Second thin wall section 22 Thick wall section 22A First thick wall section 22B Second thick wall section 23 Center point 24 Protrusion 24A First protrusion 24B Second protrusion 25 Ellipses 25A The first ellipse 25B The second ellipse 26 tangent 26A-1, 26B-1 First tangent 26A-2, 26B-2 First tangent 27 contacts 27A-1 Contact 27B-1 Contact 28A-1 Contact 28B-1 Contact 28 Ellipse center point 28A The center point of the first ellipse 28B Second ellipse center point 30 Ultrasonic Sensors 31 vehicles 71 Transmitter Circuit 73 Housing Cases A outer diameter B Opening length C Minimum opening length D wall thickness DX diameter DY diameter

Claims

1. It has a bottomed cylindrical case, The case comprises a first thin wall portion formed along the inner wall surface of the case, A first thick wall portion having a first projection that protrudes from the inner wall surface of the case toward the internal space of the case, A second thin wall portion formed along the inner wall surface of the case, An ultrasonic sensor device having a second thick wall portion having a second protrusion that projects from the inner wall surface of the case toward the internal space of the case, In a cross-section parallel to the inner bottom surface of the case, the first thin wall portion and the second thin wall portion face each other, and the first thick wall portion and the second thick wall portion face each other. The X-axis is defined as the direction passing through the center of the case and determining the directionality of the ultrasonic sensor device to be wide-angle directivity, and the Y-axis is defined as the direction passing through the center of the case and determining the directionality of the ultrasonic sensor device to be narrow-angle directivity. All or part of the first projection and the second projection have a curved shape that is symmetrical with respect to the X-axis. Let DX be the length of the first and second protrusions on the X-axis, and let DY be the length on the Y-axis at the midpoint of the lengths of the first and second protrusions on the X-axis. In the internal space of the case, when the opening length from the first thin wall portion to the second thin wall portion is B, DX has a length of 20.5% or more of B, and DY has a length of 34.1% or more of B. Ultrasonic sensor device.

2. The shapes of the first and second protrusions include a curve symmetric with respect to the X-axis and two tangent lines that are tangent to the curve symmetric with respect to the X-axis, wherein the two tangent lines extend toward the outer circumference of the case. The ultrasonic sensor device according to claim 1.

3. The aforementioned DX and the aforementioned DY The relationship DY - B × 0.136 < (DX × 0.5 + B × 0.273) < DY + B × 0.136 is satisfied. The ultrasonic sensor device according to claim 1.

4. The curve that is symmetric with respect to the aforementioned x-axis is either a parabola, a quadratic curve, or a circle. The ultrasonic sensor device according to claim 1.

5. The ultrasonic sensor device comprises the device described in any one of claims 1 to 4. vehicle.

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