Ultrasonic sensor head and ultrasonic sensor

Abstract

The present invention discloses a sensor head for an ultrasonic sensor and an ultrasonic sensor having the sensor head; the sensor head includes a flat transceiver and a cylindrical support; the transceiver is a circular structure with a diameter the same as the radial cross-sectional diameter of the support, and the transceiver is located at the top of the support; two through slots are provided on the support and near the transceiver, the through slots passing through the body of the support, the length direction of the through slots being provided along the circumference of the support, and the two through slots being symmetrically arranged relative to the central axis of the support. The sensor head of the present invention narrows the detection angle in a certain direction according to the needs of use. When used for distance detection in motor vehicles, it can increase the detection distance, which is of great significance for the application of ultrasonic sensors in low-speed automatic driving and automatic parking, as well as in the collision avoidance of trucks, buses, and engineering vehicles.

Description

Technical Field

[0001] The present invention relates to the technical field of ultrasonic sensors, and in particular to a sensor head for an ultrasonic sensor and an ultrasonic sensor having the sensor head. Background Art

[0002] Ultrasonic sensors are devices that convert signals from other energy sources into the required ultrasonic signal or energy. Ultrasonic sensors used in automotive collision avoidance primarily utilize piezoelectric transducers. During operation, the ECU generates a pulse signal with a frequency of 4-32 cycles, based on the sensor's frequency and actual operating requirements. This signal's frequency matches the sensor's frequency. A pulse amplifier circuit then generates a high-voltage pulse for the ultrasonic sensor, which then emits an ultrasonic wave. When the ultrasonic signal encounters an obstacle, it reflects back and is received by the sensor. The receiving amplifier circuit amplifies the signal and transmits it to the ECU, which analyzes the signal to detect the distance to the obstacle.

[0003] Traditional ultrasonic sensors used in motor vehicles have been mainly used to detect obstacles within 4.5 meters to help drivers avoid collisions. However, with the rapid technological changes in the automotive field, higher requirements have been placed on ultrasonic sensors, that is, they need to measure farther.

[0004] Combine Figure 6 The existing ultrasonic sensors have a vertical beam angle (detection angle) of about 50 degrees. If used for long-distance detection, it is easy to detect the ground or gravel and produce false alarms. Therefore, the existing ultrasonic sensors cannot accurately detect obstacles at a long distance. Summary of the Invention

[0005] The first object of the present invention is to provide a sensor head for an ultrasonic sensor, which solves the problem that the ultrasonic sensor cannot accurately detect distant obstacles due to the wide angle of the ultrasonic waves emitted. The first object of the present invention is achieved by the following technical solutions:

[0006] A sensor head for an ultrasonic sensor comprises a flat transceiver for receiving and sending signals and a cylindrical support portion; the transceiver is a circular structure having a diameter the same as a radial cross-sectional diameter of the support portion, and the transceiver is located at the top end of the support portion; the sensor head is characterized in that two through grooves are provided on the support portion and near the transceiver, the through grooves passing through the body of the support portion, the length direction of the through grooves being provided along the circumference of the support portion, and the two through grooves being symmetrically arranged relative to the central axis of the support portion.

[0007] Specifically, the diameter of the support portion is between φ12 and φ16 mm; the straight length L of the through groove is between 5 and 10 mm; and the width H of the through groove is between 0.5 and 2 mm.

[0008] Preferably, the straight line length L is 8 mm.

[0009] Preferably, the width H is 1 mm.

[0010] Specifically, the support portion and the transceiver portion are an integrally formed structure.

[0011] The second object of the present invention is to provide an ultrasonic sensor using the sensor head described in the technical solution of the first object; the second object of the present invention is achieved by the following technical solution:

[0012] An ultrasonic sensor comprises a sensor body, a piezoelectric device, and a PCB board; the PCB board is arranged inside the sensor body and has a plurality of electronic components thereon; the PCB board is electrically connected to the piezoelectric device; it is characterized in that it also includes the sensor head described in the first technical solution, the sensor head is mounted on the end of the sensor body; the piezoelectric device is closely attached to the inner side of the transceiver portion of the sensor head.

[0013] Specifically, the piezoelectric device is attached to the inner side of the transceiver.

[0014] Furthermore, it also includes a protective cover, which is arranged on the sensor head and covers the through groove.

[0015] Furthermore, the ultrasonic sensor also has a probe electrically connected to the outside, and the probe is electrically connected to the PCB board.

[0016] Preferably, the interior of the ultrasonic sensor is filled with waterproof glue.

[0017] Beneficial technical effects of the present invention:

[0018] The ultrasonic sensor head of this invention features a slotted support, which modifies the vibration mode of the transceiver in a specific direction, thereby narrowing the ultrasonic sensor's detection angle. When used for distance detection in motor vehicles, this ultrasonic sensor increases its detection range by narrowing the detection angle in the vertical direction without causing false alarms due to ground contact. This holds significant potential for ultrasonic sensor applications in low-speed autonomous driving and automated parking, as well as collision avoidance for trucks, buses, and construction vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A perspective view of the sensor head of the present invention is given.

[0020] Figure 2 A side view of the sensor head of the present invention is given.

[0021] Figure 3 A cross-sectional view of the sensor head of the present invention is given.

[0022] Figure 4 A cross-sectional view of an ultrasonic sensor according to the present invention is given.

[0023] Figure 5 An exploded diagram of the ultrasonic sensor of the present invention is given.

[0024] Figure 6 A diagram of the detection angle in the vertical direction of a motor vehicle using an ultrasonic sensor of the prior art is given.

[0025] Figure 7 The target detection range in the vertical direction of a motor vehicle to which the ultrasonic sensor of the present invention is applied is given.

[0026] Figure 8 A diagram of the detection angle in the vertical direction of a motor vehicle to which the ultrasonic sensor of the present invention is applied is given.

[0027] Figure 9 A schematic diagram of the detection range of a motor vehicle using the ultrasonic sensor of the present invention during automatic parking is provided.

[0028] Figure 10 A schematic diagram of the detection range of a motor vehicle using the ultrasonic sensor of the present invention during low-speed driving is provided.

[0029] Figure 11 A simulation diagram of the detection angle of an ultrasonic sensor in the prior art is given.

[0030] Figure 12 The detection angle waveform diagram of the ultrasonic sensor in the prior art is given.

[0031] Figure 13 A simulation diagram of the detection angle of the ultrasonic sensor of the present invention is given.

[0032] Figure 14 The detection angle waveform diagram of the ultrasonic sensor of the present invention is given. DETAILED DESCRIPTION

[0033] In order to more clearly understand the technical solution of the present invention, the present invention is further described below with reference to the accompanying drawings and specific embodiments.

[0034] It should be noted that, unless otherwise specified, all technical and scientific terms used in this solution have the same meanings as commonly understood by ordinary technicians in the technical field to which this solution belongs.

[0035] In this solution, unless otherwise specified, directional words such as "up, down, vertical, axis, front, back" are usually used with reference to the directions shown in the accompanying drawings, but the above directional words are not used to limit this solution.

[0036] Combine Figure 4 、 5 This embodiment provides an ultrasonic sensor, including a sensor body 40, a sensor head 10, a piezoelectric device 20, a protective cover 30, and a PCB 50. The sensor head 10 is mounted at the end of the sensor body 40. The PCB 50 is disposed within the sensor body 40 and has several electronic components thereon. The piezoelectric device 20 is mounted within the sensor head 10 and is electrically connected to the PCB 50. The ultrasonic sensor also includes a probe 51 for external electrical connection, which is electrically connected to the PCB 50. The protective cover 30 is mounted on the sensor head 10.

[0037] Combine Figures 1 to 3 The sensor head 10 provided by the present invention includes a flat-plate transceiver 11 and a cylindrical support portion 12; the transceiver 11 is a circular structure, and its diameter is the same as the radial cross-sectional diameter of the support portion 12. The transceiver 11 is located at the top end of the support portion 12, and the support portion 12 is used to support the transceiver 11. The support portion 12 and the transceiver 11 are an integrally molded structure. The transceiver 11 is located at the end of the ultrasonic sensor and is used to transmit ultrasonic signals outward and receive echo signals.

[0038] Two through-slots 13 are defined on the support portion 12 near the transceiver 11. These slots 13 extend through the support portion 12, extending along its circumference and symmetrically about its central axis. The angle of the ultrasonic waves emitted by the sensor head 10 is controlled by controlling the length L of the slots 13. A protective cover 30 covers the slots 13, preventing them from being exposed.

[0039] In this embodiment, the piezoelectric device 20 is a piezoelectric ceramic piece, and the piezoelectric device 20 is adhesively fixed to the inner side of the transceiver portion 11 of the detection head.

[0040] In some specific embodiments, the sensor head 10 has a natural vibration frequency of approximately 51KHz and a natural vibration mode. When a driving pulse signal consistent with the natural vibration frequency of the sensor head 10 is applied to the piezoelectric device 20, the piezoelectric device 20 will deform and drive the sensor head 10 to generate a vibration with a peak value of approximately 500 nanometers through adhesive coupling; of course, different diaphragm structures have different vibration modes.

[0041] The PCB board 50 is loaded with a driving circuit for driving the piezoelectric device 20 to vibrate. The specific circuit structure can use the circuit structure commonly used in the prior art, and the details will not be repeated here.

[0042] The size of the sensor head of the ultrasonic sensor currently available on the market (the radial cross-sectional diameter of the support portion 12) is between φ12 and φ16 mm; in one embodiment, the slot length L of the through slot 13 is 5 to 10 mm, where the slot length L is a straight length, not an arc length; the width H of the barrel slot 13 is 0.5 to 2 mm.

[0043] Combine Figure 7 When the ultrasonic sensor of the present invention is applied to a motor vehicle, in order to extend the detection distance (target detection range) and reduce false positives, the detection angle of the motor vehicle in the vertical direction needs to be narrowed. In this embodiment, when the slot length L is 8 mm, the detection angle of the ultrasonic sensor of the sensor head 10 in a certain direction (for example, the vertical direction) is narrowed to 20 degrees. Figure 8 A diagram of the detection angle of a motor vehicle in the vertical direction using this embodiment is given. In a specific embodiment, the width H of the slot is 1 mm, which can make the slotting process operation more convenient.

[0044] Preferably, the interior of the ultrasonic sensor is filled with waterproof glue so that the ultrasonic sensor itself has a waterproof function.

[0045] refer to Figure 11 、 12 The existing ultrasonic sensor has no slots, so the vibration mode of the transceiver 11 of the sensor head 10 is isotropic and its vibration area is nearly circular. Figure 13 、 14 The slot arrangement of the present application is equivalent to changing the original vibration mode within the influence area of the through-slot 13, thereby optimizing the vibration area into an elliptical structure. By adjusting the position of the ultrasonic sensor during use, the ultrasonic sensor's transmission angle in a certain direction can be narrowed. For example, adjusting the ultrasonic sensor's position so that the length of the through-slot 13 is arranged horizontally can narrow the ultrasonic sensor's detection angle in the vertical direction.

[0046] The ultrasonic sensor of the present invention is used for distance detection of motor vehicles, which can increase the detection distance and will not detect the ground and cause false alarms. It is very useful for the application of ultrasonic sensors in low-speed automatic driving (refer to Figure 10 ) and automatic parking (reference Figure 9 ) and the collision avoidance of trucks, buses and engineering vehicles are of great significance.

[0047] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements that fall within the spirit and principles of the present invention and do not involve inventive steps shall be included within the scope of protection of the present invention.

Claims

1. A sensor head for an ultrasonic sensor, comprising a flat transceiver for receiving and transmitting signals and a cylindrical support; the transceiver is a circular structure having a diameter equal to a radial cross-sectional diameter of the support, and the transceiver is located at the top of the support; characterized in that: Two through grooves are provided on the support portion and near the transceiver portion for optimizing the vibration area of the transceiver portion into an elliptical structure. The through grooves pass through the body of the support portion, and the length direction of the through grooves is along the circumference of the support portion. The two through grooves are symmetrically arranged relative to the central axis of the support portion. The angle of the ultrasonic wave emitted by the sensor head is controlled by controlling the slot length of the through grooves.

2. The sensor head according to claim 1, wherein: The diameter of the support portion is between φ12 and φ16 mm; the straight length L of the through slot is between 5 and 10 mm; and the width H of the through slot is between 0.5 and 2 mm.

3. The sensor head according to claim 2, wherein: The straight line length L is 8 mm.

4. The sensor head according to claim 2, wherein: The width H is 1 mm.

5. The sensor head according to any one of claims 1 to 4, characterized in that: The supporting portion and the transceiver portion are an integrally formed structure.

6. An ultrasonic sensor comprising a sensor body, a piezoelectric device, and a PCB; the PCB is disposed inside the sensor body and has a plurality of electronic components thereon; the PCB is electrically connected to the piezoelectric device; and is characterized in that: It also includes the sensor head according to any one of claims 1 to 5, wherein the sensor head is installed at the end of the sensor body; and the piezoelectric device is closely attached to the inner side of the transceiver of the sensor head.

7. The ultrasonic sensor according to claim 6, characterized in that The piezoelectric device is attached to the inner side of the transceiver.

8. The ultrasonic sensor according to claim 6, wherein: It also includes a protective cover, which is arranged on the sensor head and covers the through slot.

9. The ultrasonic sensor according to any one of claims 6 to 8, characterized in that: The ultrasonic sensor further comprises a probe electrically connected to the outside, and the probe is electrically connected to the PCB board.

10. The ultrasonic sensor according to claim 9, characterized in that The interior of the ultrasonic sensor is filled with waterproof glue.

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