CN116338698A

CN116338698A - Concealed ultrasonic sensor and device thereof

Info

Publication number: CN116338698A
Application number: CN202111598508.2A
Authority: CN
Inventors: 陈富; 杨顺钊; 韩赟
Original assignee: Audiowell Electronics Guangdong Co ltd
Current assignee: Audiowell Electronics Guangdong Co ltd
Priority date: 2021-12-24
Filing date: 2021-12-24
Publication date: 2023-06-27

Abstract

The application relates to a concealed ultrasonic sensor and a device thereof, comprising: the shell is internally provided with a piezoelectric ceramic piece; the shell is concavely provided with an inner cavity, and the piezoelectric ceramic piece is arranged in the inner cavity; the shell is provided with a first part and a second part, the first part is connected with the second part, and the inner cavity is communicated with the first part and the second part; the first part is provided with an end face and a connecting face opposite to the end face, and the connecting face is connected with the second part; the first part is cut from the end face to the connecting face, the cut surface of the first part is trapezoid, and the direction from the end face to the connecting face is gradually enlarged. Compared with the traditional cylindrical ultrasonic sensor, the ultrasonic sensor has the advantages that the installation of the external object with the plane can be matched, and the installation of the external object with the curved surface can be compatible.

Description

Concealed ultrasonic sensor and device thereof

Technical Field

The application relates to the technical field of ultrasonic sensors, in particular to a concealed ultrasonic sensor and a device thereof.

Background

When the ultrasonic sensor is installed, a hole is formed in a car door or a bumper to expose a probe, and a vibration working face of the probe is directly contacted with air to ensure effective transmission of ultrasonic signals. Ultrasonic sensors are assigned to driver assistance devices and provide information about the vehicle environment. Driver assistance devices, such as parking assistance systems, systems for blind spot monitoring, systems for distance maintenance, lane monitoring systems, brake assistance systems, etc. However, such ultrasonic sensors are mounted on a vehicle door or bumper without being covered, are arranged in continuous grooves or through openings in the vehicle door or bumper, and are externally visible. The whole appearance of the car body is affected by the perforation on the bumper or the car door, and the safety and reliability of the bumper and the car door can be reduced to a certain extent by the perforation. Meanwhile, in order to facilitate the installation of the ultrasonic sensor, the aperture diameter of the opening is generally larger than the outer diameter of the ultrasonic sensor, and the ultrasonic sensor is wrapped by a rubber sleeve and assembled on a vehicle door or a bumper.

The traditional concealed ultrasonic sensor has strict requirements on the assembly position. When the ultrasonic sensor is assembled, the ultrasonic sensor is required to be contacted with a vehicle door or a bumper in a flat position, and the vehicle door or the bumper cannot have radian. The mounting environment requirement reduces the position selectivity of the sensor mounting, increases the cost of the assembly process and the assembly working hours, and has larger mounting limitation. Meanwhile, in the practical use of the ultrasonic sensor, because the limitation of a vehicle door (a bumper) can generate interference clutter, clutter signals are mixed in conventional signals to form misjudgment and misinformation, and the driving safety is seriously influenced.

Disclosure of Invention

In order to overcome the problems in the related art, the application provides a hidden ultrasonic sensor and a device thereof, wherein the hidden ultrasonic sensor can be suitable for curved surface installation, a corresponding assembled vehicle door or bumper does not need to be provided with holes, signals are stable in the use process, and clutter interference is shielded.

A first aspect of the present application provides a concealed ultrasonic sensor comprising: the shell is internally provided with a piezoelectric ceramic piece; the shell is concavely provided with an inner cavity, and the piezoelectric ceramic piece is arranged at the bottom of the inner cavity; the shell is provided with a first part and a second part, the first part is connected with the second part, the first part and the second part are integrally formed, and the inner cavity is communicated with the first part and the second part; the first part is provided with an end face and a connecting face opposite to the end face, and the connecting face is connected with the second part; the first part is cut along the direction from the end face to the connecting face, the cut surface of the first part is trapezoid, the direction from the end face to the connecting face is gradually enlarged, and the piezoelectric ceramic piece is arranged in the direction close to the end face. Compared with the traditional cylindrical ultrasonic sensor, the ultrasonic sensor has the advantages that the installation of the planar metal plate is matched, and the installation of the curved metal plate can be compatible.

Preferably, the second portion has a square cross section, in the same direction as the first portion. Providing convenient conditions for the fixation and installation of the ultrasonic sensor.

Preferably, the housing is made of a high-rigidity material, the sound velocity of the high-rigidity material is 5000-18000 m/s, and the density of the high-rigidity material is 6.5-8.5 g/cm3. And the high-rigidity material is adopted to reduce the ultrasonic transmission loss between the vibration surface and the metal matching surface of the sensor, so that the signal transmission efficiency is improved. The sound velocity of the high-rigidity material is 5000-18000 m/s, the density of the high-rigidity material is 6.5-8.5 g/cm < 3 >, the transmission energy loss of sound waves is minimum, and the echo signal is maximum.

Preferably, the ratio of the diameter d1 of the end face to the diameter d2 of the connecting face is d 1/d2=1: 1 to 1:5. the ratio of the diameters can be adjusted in the range according to actual needs, and the method can be suitable for installation environments of curved car doors or bumpers with different bending degrees.

A second aspect of the present application provides a concealed ultrasonic sensor apparatus comprising: the hidden ultrasonic sensor is sleeved with a fixed rubber sleeve at the outer side, the end face of the hidden ultrasonic sensor is exposed out of the fixed rubber sleeve, a matching layer is arranged on the end face of the hidden ultrasonic sensor, and the matching layer is connected with an external object; part of the fixing rubber sleeve is fixed on a fixing piece, the fixing piece is provided with a cavity, the cavity is connected with an opening, part of the fixing rubber sleeve is arranged in the cavity, other parts of the fixing rubber sleeve are exposed out of the fixing piece through the opening, the fixing rubber sleeve is provided with a top surface, and the top surface is connected with an external object. The device is applicable to being installed inside metal bumper or metal door intermediate layer, carries out range finding or obstacle discernment through the ultrasonic wave penetrating metal layer, avoids metal bumper or door trompil. Meanwhile, the concealed ultrasonic sensor adopts a trapezoid design, and can be suitable for installation environments of curved car doors or bumpers with different bending degrees.

Preferably, the fixing gum cover is provided with an abutting part, a fixing part and a connecting part for connecting the abutting part with the fixing part, the abutting part abuts against the external object, the fixing part is arranged in the cavity, and the connecting part abuts against the opening. So that the concealed ultrasonic sensor is effectively fixed in the fixing piece under the action of the fixing rubber sleeve.

Preferably, the outer side of the abutting portion is a circumference. The abutting part can be tightly contacted with an external object, residual vibration is reduced, the sensor is prevented from being affected and interfered by other vibration, and the accuracy of the device is ensured.

Preferably, the vibration-stopping pad is sleeved on the outer side of the fixed rubber sleeve, and the vibration-stopping pad is in contact with the external object. The vibration-stopping pad reduces residual vibration or transmission of other vibration in the environment, reduces interference and ensures the accuracy of signal transmission and reception.

Preferably, the concealed ultrasonic sensor is connected with filling cotton made of multi-suction material, and the filling cotton is arranged in the cavity. The device is used for absorbing ultrasonic waves emitted by the hidden ultrasonic sensor after vibration and eliminating interference signals of the emitted ultrasonic waves.

Preferably, a void area between the outer side of the housing and the external object is filled with the fixing gum cover. The clutter interference can be effectively reduced through the inhibition and the buffering of the fixed rubber sleeve.

The technical scheme that this application provided can include following beneficial effect:

1. the matching layer is used for bonding the concealed ultrasonic sensor and the metal plate, so that the open pore installation of the vehicle door or the bumper is avoided, and the installation requirement of the assembly without the open pore is met.

2. The concealed ultrasonic sensor is designed by adopting a trapezoid structure, so that the area of the concealed ultrasonic sensor in mounting contact with a metal plate is smaller, the concealed ultrasonic sensor is suitable for mounting a curved surface of a bumper or a vehicle door with radian, and can be suitable for mounting various vehicle doors with large radians or bumpers.

3. The high-rigidity concealed ultrasonic sensor shell is contacted with the vehicle door or the bumper through the matching layer, so that the energy loss of ultrasonic waves in the transmission process can be reduced, and the detection capability and the signal transmission efficiency are enhanced.

4. The outside of trapezoidal hidden ultrasonic sensor wraps up with fixed gum cover, and unnecessary space area makes the received signal more stable after fixed gum cover fills, reduces the erroneous judgement that causes because of clutter interference.

5. Inside the fixing piece and near the sealing surface of the hidden ultrasonic sensor are filled cotton made of porous sound-absorbing materials, and after absorption, ultrasonic waves are emitted, so that misjudgment caused by the emitted sound waves is eliminated.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.

Drawings

The foregoing and other objects, features and advantages of the application will be apparent from the following more particular descriptions of exemplary embodiments of the application as illustrated in the accompanying drawings wherein like reference numbers generally represent like parts throughout the exemplary embodiments of the application.

FIG. 1 is a schematic structural view of a concealed ultrasonic sensor and apparatus thereof according to an embodiment of the present application;

FIG. 2 is an exploded schematic view of a concealed ultrasonic sensor and apparatus thereof shown in an embodiment of the present application;

FIG. 3 is a schematic view of a portion of a concealed ultrasonic sensor and apparatus thereof according to an embodiment of the present application;

FIG. 4 is a schematic structural view of a housing of a concealed ultrasonic sensor shown in an embodiment of the present application;

fig. 5 is a schematic structural view of a concealed ultrasonic sensor according to an embodiment of the present invention.

Matching layer 3 of housing 1

Inner cavity 11 fixing piece 4

First portion 12 cavity 41

End face 121 opening 42

Vibration-damping pad 5 with connection surface 122

The second portion 13 has a central through hole 51

Piezoelectric ceramic piece 14 filled with cotton 6

External object 7 of fixed rubber sleeve 2

Top surface 21 obstacle 8

The abutment 22 emits sound waves 9

The fixing portion 23 reflects the acoustic wave 10

Connection portion 24

Detailed Description

Preferred embodiments of the present application will be described in more detail below with reference to the accompanying drawings. While the preferred embodiments of the present application are shown in the drawings, it should be understood that the present application may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

The terminology used in the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. As used in this application and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any or all possible combinations of one or more of the associated listed items.

It should be understood that although the terms "first," "second," "third," etc. may be used herein to describe various information, these information should not be limited by these terms. These terms are only used to distinguish one type of information from another. For example, a first message may also be referred to as a second message, and similarly, a second message may also be referred to as a first message, without departing from the scope of the present application. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present application, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.

The following describes the technical scheme of the embodiments of the present application in detail with reference to the accompanying drawings.

Ultrasonic sensors are sensors that convert ultrasonic signals into other energy signals (typically electrical signals). Ultrasonic waves are mechanical waves with vibration frequencies higher than 20 kHz. It has the characteristics of high frequency, short wavelength, small diffraction phenomenon, good directivity, capability of being used as rays to directionally propagate, and the like. The penetration of ultrasound into liquids, solids is great, especially in solids that are opaque to sunlight. The ultrasonic waves can be obviously reflected to form a reflected echo when encountering impurities or interfaces, and the Doppler effect can be generated when the ultrasonic waves collide with a living body. Ultrasonic sensors are widely used in industry, national defense, biomedical science, automobile assisted driving, and the like.

Referring to fig. 1, 2 and 3, an embodiment of the present application shows a concealed ultrasonic sensor and a device thereof, which are applied to the field of automobile auxiliary driving and are concealed ultrasonic sensors with complex installation. The structure is suitable for being installed inside a metal bumper or a metal car door interlayer, and distance measurement or obstacle 8 recognition is carried out by penetrating through a metal layer through ultrasonic waves, so that the metal bumper or car door is prevented from being perforated. The concealed ultrasonic sensor comprises: the shell 1, be equipped with piezoceramics piece in the shell 1, this piezoceramics piece is electrified and is produced vibration, produces ultrasonic signal, begins work. The concealed ultrasonic sensor emits sound waves 9, reflects sound waves 10 after encountering an obstacle 8, receives the reflected sound waves 10 and processes the reflected sound waves 10. In this embodiment, the concealed type ultrasonic sensor is a closed type ultrasonic sensor commonly called an ultrasonic probe, the piezoelectric ceramic plate 14 is disposed in a closed cavity, and vibration of the piezoelectric ceramic plate 14 is transmitted through vibration of the housing 1. An ultrasonic probe is a device that transmits and receives ultrasonic waves during ultrasonic detection. The performance of the probe directly affects the characteristics of the ultrasonic waves and affects the detection performance of the ultrasonic waves. The probe used in ultrasonic detection is a transducer which utilizes the piezoelectric effect of materials to realize electric energy and acoustic energy conversion. The key component in the probe is the wafer, which is a single or multi-crystalline sheet with piezoelectric effect, which is used to convert electrical and acoustic energy into each other. In this embodiment, the wafer is a piezoelectric ceramic wafer. The working principle of the ultrasonic probe is as follows: 1. ultrasonic waves are transmitted and received by the piezoelectric effect. 2.640V alternating voltage is applied to the silver layer of the piezoelectric wafer, so that two metal polar plates with the same area and a certain distance are respectively provided with the same amount of heterogeneous charges to form an electric field, the electric field force exists when the electric field exists, the piezoelectric wafer is positioned in the electric field, deformation occurs under the action of the electric field force, and the deformation effect occurs under the action of the alternating electric field force, which is called reverse piezoelectric effect, and is also the process of transmitting ultrasonic waves. 3. The ultrasonic wave is mechanical wave, the mechanical wave is generated by vibration, the ultrasonic wave finds out that the defect causes the defect vibration, part of the defect vibration returns along the original path, and the ultrasonic wave has certain energy and then acts on the piezoelectric crystal, so that the piezoelectric crystal generates an alternating electric field under the action of alternating pulling and pressure, and the effect is called positive piezoelectric effect and is a process of receiving the ultrasonic wave. The positive and negative piezoelectric effects are collectively referred to as piezoelectric effects.

Referring to fig. 4, in some embodiments, the housing 1 is concavely provided with an inner cavity 11, and a piezoceramic sheet 14 is disposed at the bottom inside the inner cavity 11. In this embodiment, the housing 1 is provided with a first portion 12 and a second portion 13, the first portion 12 and the second portion 13 are connected with each other, the first portion 12 and the second portion are integrally formed, the inner cavity 11 is communicated with the first portion 12 and the second portion 13, and the piezoelectric ceramic plate 14 is disposed in the first portion 12. In this embodiment, the inner cavity 11 is a circular groove with a uniform inner diameter, and is cylindrical, and the circular groove is concavely formed on the first portion 12 through the second portion 13, and does not penetrate the first portion 12, and the piezoceramic sheet 14 is disposed on the bottom of the first portion 12. The round groove is arranged to be consistent in inner diameter, so that the setting and fixing of internal components are facilitated, and meanwhile, the sensitivity and the stability of signals of the concealed ultrasonic sensor are guaranteed.

Referring to fig. 3, 4 and 5, in some embodiments, the first portion 12 is provided with an end surface 121 and a connection surface 122 opposite to the end surface 121, the end surface 121 is a vibration surface, the piezoelectric ceramic sheet 14 is disposed in a direction approaching the end surface, and the connection surface 122 is connected to the second portion 13. The first portion 12 is cut in a direction from the end surface 121 toward the connection surface 122, and is vertically cut, and the cut surface of the first portion 12 is trapezoidal, that is, the direction from the end surface 121 toward the connection surface 122 becomes gradually larger. In this embodiment, the end surface 121 and the connection surface 122 are both circular planar surfaces.

Referring to fig. 3 and 4, in some embodiments, the second portion 13 may have a square cross-section, as the first portion 12 is cut in the same direction, i.e., perpendicular from the end surface 121 to the connecting surface 122. In this embodiment, the second portion 13 has a rectangular cross section, and in other embodiments, the cross section may be other square. In this embodiment, the second portion 13 has a rectangular cross section, i.e. the second portion 13 is cylindrical for easy fixing and mounting.

Referring to fig. 3 and 4, in some embodiments, the casing 1 is made of a material with high rigidity, such as stainless steel, alloy steel, carbon steel, and the like, and has close sound velocity and density, so as to reduce the transmission loss of ultrasonic waves between the vibration surface and the metal matching surface of the sensor, and improve the signal transmission efficiency. In this embodiment, the sound velocity of the high-rigidity material is 5000-18000 m/s, the density is 6.5-8.5 g/cm3, the transmission energy loss of sound waves is minimum, and the echo signal is maximum.

In order to keep the transmission and reception losses low, the transmission surface of the ultrasonic sensor must be mechanically firmly connected to the bumper or a loss-free coupling element must be formed between the transmission surface of the ultrasonic sensor and the bumper. Referring to fig. 3 and 4, the housing 1 of the concealed ultrasonic sensor adopts a trapezoidal design with a narrow top and a wide bottom, and compared with the traditional cylindrical ultrasonic sensor, the concealed ultrasonic sensor can adapt to the installation of a planar external object 7 and also can be compatible with the installation of the curved external object 7. The ratio between the upper bottom/lower bottom diameters (i.e., the diameter of end face 121/the diameter of connecting face 122) of the conventional concealed ultrasonic sensor is fixed to d1/d2=1: 1, the ability to accommodate curved surface installations is limited. In the case 1 of the concealed type ultrasonic sensor in the present embodiment, the ratio of the diameter d1 of the end surface 121 to the diameter d2 of the connection surface 122 is d 1/d2=1: 1 to 1:5. can be found at d 1/d2=1: 1 to 1:5, the device can be suitable for installing curved surface external objects 7 with different bending degrees, and the selection range of the installation positions of the safety bars or the doors is wide. The concealed ultrasonic sensor is designed by adopting a trapezoid structure, so that the area of installation contact with an external object 7 is smaller, the concealed ultrasonic sensor is suitable for installation of a curved surface of a bumper or a vehicle door with radian, and can be suitable for installation of various vehicle doors with large radians or bumpers. In this embodiment, the end face 121 is a transmission surface of the ultrasonic sensor.

Referring to fig. 1 and 2, a device using the hidden ultrasonic sensor comprises the hidden ultrasonic sensor, wherein a fixed rubber sleeve 2 is sleeved outside the hidden ultrasonic sensor, an end face 121 is exposed out of the fixed rubber sleeve 2, a matching layer 3 is arranged on the end face 121, and the matching layer 3 is connected with an external object 7. In this embodiment, the matching layer 3 is a lossless coupling element. Part of the fixed rubber sleeve 2 is fixed on a fixing piece 4, the fixing piece 4 is provided with a cavity 41, the cavity 41 is connected with an opening 42, part of the fixed rubber sleeve 2 is arranged in the cavity 41, other parts of the fixed rubber sleeve 2 are exposed out of the fixing piece 4 through the opening 42, the fixed rubber sleeve 2 is provided with a top surface 21, and the top surface 21 is connected with an external object 7. In this embodiment, the external object 7 is a metal bumper or a metal door sandwich of a vehicle. The matching layer 3 is used for bonding the concealed ultrasonic sensor and the metal bumper or the metal door interlayer of the vehicle, so that the installation of a door or a bumper opening is avoided, and the installation requirement of an assembly non-opening is met. In this embodiment, the matching layer 3 is also disposed in the fixing rubber sleeve 2, so that the fixing rubber sleeve 2 directly abuts against the external object 7, and interference of residual vibration and noise is reduced.

Referring to fig. 1 and 2, the fixing gum cover 2 includes an abutting portion 22, a fixing portion 23, and a connecting portion 24 connecting the abutting portion 22 and the fixing portion 23. In this embodiment, the abutting portion 22 abuts against the external object 7, the fixing portion 23 is disposed in the cavity 41, and the connecting portion 24 abuts against the edge of the opening 42, so that the first portion 12 of the concealed type ultrasonic sensor is exposed to the outside of the fixing member 4, and the second portion 13 is disposed in the cavity 41. Because the housing 1 of the concealed ultrasonic sensor is narrow at the upper part and wide at the lower part, the opening 42 clamps the housing, the narrow part at the upper part is exposed outside the opening 42, and the wide part at the lower part is arranged in the cavity 41. In this embodiment, the inner wall of the fixed rubber sleeve 2 is designed according to the shape of the casing 1, so that the concealed ultrasonic sensor is tightly covered, and residual vibration is not generated in the vibration process to interfere with the transmission of signals.

Referring to fig. 1 and 2, in the present embodiment, the fixing rubber sleeve 2 is made of soft material, and the outer side of the abutting portion 22 is a circumference, which is favorable for deformation of the abutting portion 22, so that the abutting portion 22 is in close contact with the external object 7, and can adapt to the external objects 7 with different shapes and ensure that the external objects can be in close contact. In other embodiments, the abutment 22 may be provided with a special fit according to the shape of the external object 7. Is reliably arranged on the external object 7 and does not impair the performance of the sensor.

Referring to fig. 1 and 2, the outer sleeve of the fixed rubber sleeve 2 is also provided with a vibration-stopping pad 5, the vibration-stopping pad 5 is in contact with an external object 7, residual vibration is reduced, and meanwhile interference of external vibration on the concealed ultrasonic sensor is reduced. In this embodiment, the vibration-damping pad 5 is ring-shaped and has a central through hole 51, and the fixing rubber sleeve 2 passes through the central through hole 51 and is in close contact with the central through hole 51, so as to reduce residual vibration and reduce interference and influence caused by the transmission of vibration of the external object 7. The vibration-damping pad 5 is a flexible body that can be deformed according to the shape of the external object 7, so that the vibration-damping pad 5 can be in close contact with the external object 7 while increasing the flexibility of the vibration-damping pad 5.

Referring to fig. 1 and 2, the concealed ultrasonic sensor is connected with a filling cotton 6 made of a multi-suction material, and the filling cotton 6 is arranged in the cavity 41. In this embodiment, when the concealed ultrasonic sensor is installed in the fixing piece 4, a region, close to the sealing surface of the concealed ultrasonic sensor, inside the fixing piece 4 is filled with filling cotton 6 made of porous sound absorbing materials, and the filling cotton is used for absorbing ultrasonic waves emitted by the concealed ultrasonic sensor after vibration, and eliminating interference signals of the ultrasonic waves after vibration. The size of the filling cotton 6 is matched with the performance of the concealed ultrasonic sensor, the thickness is distributed at 1-5 mm, and the thickness of the filling cotton 6 can be adjusted by the frequency of the concealed ultrasonic sensor. In some embodiments, the filling cotton 6 is made of EPDM, dacron fiber, polyester fiber, and other porous and compact fluffy materials. In this embodiment, the filling cotton 6 fills the area of the sealing surface of the concealed type ultrasonic sensor and is in interference fit with the inside of the cavity 41.

Referring to fig. 1 and 2, in some embodiments, the device of the concealed ultrasonic sensor is assembled inside a vehicle door or a bumper, and a gap area between the outer side of a housing 1 adopting a trapezoidal design and the inside of the vehicle door or the bumper is filled with a fixed rubber sleeve 2, so that a received signal is more stable, and misjudgment caused by clutter interference is reduced. The clutter interference can be effectively reduced through the inhibition and the buffering of the fixed rubber sleeve 2. In some embodiments, the fixing rubber sleeve 2 can be made of conventional silicone rubber in the market, the density is 0.9-1.3 g/cm3, and the hardness is 30-60 HD.

Referring to fig. 1 and 2, the device of the concealed ultrasonic sensor is assembled in a vehicle door or a bumper, and the end surface 121 of the housing 1 is bonded to a portion to be mounted by using the matching layer 3. The device of the concealed ultrasonic sensor meets the requirement of non-drilling installation, and a car door or a bumper does not need to be provided with holes. The casing 1 adopts a trapezoidal design, and compared with the traditional hidden ultrasonic sensor, the vibration working surface (namely the end surface 121) of the hidden ultrasonic sensor reduces the relative area with a vehicle door or a bumper, and can be simultaneously matched with the installation of an arc surface and a plane external object 7.

1. the matching layer 3 is used for bonding the concealed ultrasonic sensor and the external object 7, so that the open pore installation of the vehicle door or the bumper is avoided, and the assembly non-open pore installation requirement is met.

2. The concealed ultrasonic sensor is designed by adopting a trapezoid structure, so that the area of the concealed ultrasonic sensor in mounting contact with an external object 7 is smaller, the concealed ultrasonic sensor is suitable for mounting a curved surface of a bumper or a vehicle door with radian, and can be suitable for mounting various vehicle doors with large radians or bumpers.

3. The high-rigidity concealed ultrasonic sensor shell 1 is contacted with a vehicle door or a bumper through the matching layer 3, so that the energy loss of ultrasonic waves in the transmission process can be reduced, and the detection capability and the signal transmission efficiency are enhanced.

4. The outside of trapezoidal hidden ultrasonic sensor wraps up with fixed gum cover 2, and unnecessary space area makes the received signal more stable after fixed gum cover 2 fills, reduces the erroneous judgement that causes because of clutter interference.

5. Inside the fixing piece 4 and near the sealing surface of the hidden ultrasonic sensor, a filling cotton 6 made of porous sound-absorbing materials is arranged, and after absorption, ultrasonic waves are emitted, so that misjudgment caused by the emitted sound waves is eliminated.

The embodiments of the present application have been described above, the foregoing description is exemplary, not exhaustive, and not limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the various embodiments described. The terminology used herein was chosen in order to best explain the principles of the embodiments, the practical application, or the improvement of technology in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A concealed ultrasonic sensor comprising:

the shell is internally provided with a piezoelectric ceramic piece; the shell is concavely provided with an inner cavity, and the piezoelectric ceramic piece is arranged at the bottom of the inner cavity; the shell is provided with a first part and a second part, the first part is connected with the second part, the first part and the second part are integrally formed, and the inner cavity is communicated with the first part and the second part;

the first part is provided with an end face and a connecting face opposite to the end face, and the connecting face is connected with the second part; the first part is sectioned from the end face to the connecting face, the sectioned surface of the first part is trapezoid, and the section of the first part gradually increases from the end face to the connecting face; the piezoelectric ceramic piece is arranged close to the end face direction.

2. The concealed ultrasonic sensor of claim 1 wherein: the second portion has a square cross section in the same direction as the first portion.

3. The concealed ultrasonic sensor of claim 1 wherein: the shell is made of a high-rigidity material, the sound velocity of the high-rigidity material is 5000-18000 m/s, and the density of the high-rigidity material is 6.5-8.5 g/cm < 3 >.

4. The concealed ultrasonic sensor of claim 1 wherein: the ratio of the diameter d1 of the end face to the diameter d2 of the connecting face is d 1/d2=1: 1 to 1:5.

5. a concealed ultrasonic sensor apparatus comprising:

the hidden ultrasonic sensor according to any one of claims 1-4, wherein a fixed rubber sleeve is sleeved outside the hidden ultrasonic sensor, the end face is exposed out of the fixed rubber sleeve, a matching layer is arranged on the end face, and the matching layer is connected with an external object;

part of the fixing rubber sleeve is fixed on a fixing piece, the fixing piece is provided with a cavity, the cavity is connected with an opening, part of the fixing rubber sleeve is arranged in the cavity, other parts of the fixing rubber sleeve are exposed out of the fixing piece through the opening, the fixing rubber sleeve is provided with a top surface, and the top surface is connected with an external object.

6. The concealed ultrasonic sensor apparatus of claim 5 wherein: the fixed gum cover is equipped with butt portion, fixed part, connection butt portion with the connecting portion of fixed part, butt portion with the external object butt, fixed part locates in the cavity, connecting portion with the opening butt.

7. The concealed ultrasonic sensor apparatus of claim 6 wherein: the outer side of the abutting part is a circumference.

8. The concealed ultrasonic sensor apparatus of claim 5 wherein: the vibration-stopping pad is sleeved on the outer side of the fixed rubber sleeve and is contacted with an external object.

9. The concealed ultrasonic sensor apparatus of claim 5 wherein: the hidden ultrasonic sensor is connected with filling cotton made of multi-suction materials, and the filling cotton is arranged in the cavity.

10. The concealed ultrasonic sensor apparatus of claim 5 wherein: and a gap area between the outer side of the shell and the external object is filled by the fixed rubber sleeve.