A high-frequency sensor for material identification

Abstract

This utility model relates to a high-frequency sensor for material identification, comprising a shell, an inner shell, a piezoelectric vibrator, and a matching layer. The inner shell has a conical section in its middle, with the lower inner diameter of the conical section being larger than the upper inner diameter. The piezoelectric vibrator is disposed within the conical section of the inner shell. A negative electrode solder joint is located on the upper end face of the piezoelectric vibrator, and a positive electrode solder joint is located on the lower end face. The positive and negative electrode solder joints are connected to corresponding positive and negative electrode pins via leads. Inside the inner shell, an adhesive backing is provided below the piezoelectric vibrator. Inside the outer shell, an epoxy potting layer fills the lower cavity of the inner shell. The matching layer is disposed above the piezoelectric vibrator, and a focusing surface is provided on its upper end face. This utility model, through the focusing surface on the upper end face of the matching layer, focuses the ultrasonic waves emitted by the high-frequency sensor, improving the sensor's sensitivity without increasing residual vibration, avoiding the superposition of residual vibration and multiple echo signals, and ensuring the accuracy of material identification.

Description

Technical Field

[0001] This utility model relates to the field of ultrasonic sensor technology, and in particular to a high-frequency sensor for material identification. Background Technology

[0002] Robotic vacuum cleaners typically use ultrasonic high-frequency sensors for material identification, especially when identifying floor materials. These sensors require extremely high sensitivity (echo intensity). In traditional technologies, increasing the sensitivity of high-frequency sensors often introduces unwanted vibrations, commonly known as residual vibrations, which can impair the sensor's recognition capabilities.

[0003] Ultrasonic sensors emit ultrasonic signals of a certain frequency and receive echo signals. Due to the differences in the absorption and reflection of ultrasonic waves by different materials, the ground material is determined by the intensity of the echo signal received. However, as the frequency increases, the time for the measured object to return the echo signal becomes shorter. In extreme cases, the echo signal arrives before the residual vibration of the ultrasonic sensor itself has ended. The superposition of the residual vibration and the echo signal affects the accuracy of material identification. Therefore, existing high-frequency sensors need to be improved. Utility Model Content

[0004] The purpose of this invention is to solve the problem described in the background art of existing high-frequency sensors where the return echo signal and residual vibration signal are superimposed, affecting the accuracy of distance measurement, and to provide a high-frequency sensor for material identification.

[0005] To achieve the above objectives, this utility model provides the following technical solution: A high-frequency sensor for material identification includes a shell, an inner shell, a piezoelectric vibrator, and a matching layer. The inner shell has a conical section in its middle, with the lower inner diameter of the conical section being larger than the upper inner diameter. The piezoelectric vibrator is disposed within the conical section of the inner shell. A negative electrode solder joint is located on the upper end face of the piezoelectric vibrator, and a positive electrode solder joint is located on the lower end face. The positive and negative electrode solder joints are connected to corresponding positive and negative electrode pins via leads. Inside the inner shell, an adhesive backing is provided below the piezoelectric vibrator. Inside the outer shell, an epoxy potting layer fills the lower cavity of the outer shell below the inner shell. The matching layer is disposed above the piezoelectric vibrator, and a focusing curved surface is provided on its upper end face. A stepped surface is provided on the upper part of the outer shell, with the upper radius of the stepped surface being larger than the lower radius. A damping material is filled between the cavity above the stepped surface and the upper outer wall of the outer shell. The positive and negative electrode pins extend through the epoxy potting layer to the outside of the outer shell.

[0006] In the above scheme, the focusing surface is a concave surface. With this setting, the ultrasonic wave emission is focused by the concave surface, resulting in a smaller ultrasonic angle. During detection, multiple echo reflections reduce the loss of acoustic energy, thereby improving the sensor's sensitivity without increasing residual vibration.

[0007] In the above solution, the matching layer, piezoelectric vibrator, adhesive backing, and inner shell are integrally molded into an inner shell module. After the inner shell module is installed into the outer shell, the bottom is sealed with an epoxy potting layer, and the top is sealed with a shock-absorbing material. This design ensures that the matching layer, piezoelectric vibrator, adhesive backing, and inner shell are molded as a single unit, avoiding the need for a separate matching layer. If the matching layer were molded separately, a groove for the negative electrode solder joint on the upper part of the piezoelectric vibrator would need to be reserved. It is difficult to ensure that the size and position of the negative electrode solder joint on the piezoelectric vibrator are consistent, requiring the groove to have sufficient clearance relative to the solder joint. A large groove in the matching layer would result in a loss of some of the matching layer's functionality and a reduction in the sensor's sensitivity.

[0008] This invention offers several advantages: Firstly, the high-frequency sensor for material identification features a focusing surface on the upper surface of the matching layer. This design allows the ultrasonic waves emitted by the sensor to be focused through the concave surface, resulting in a smaller angle and less energy loss during multiple echo reflections. This enhances sensor sensitivity without increasing residual vibration, preventing the superposition of residual vibration and multiple echo signals, thus ensuring accurate material identification. Secondly, the high-frequency sensor integrates the inner shell, matching layer, piezoelectric vibrator, and adhesive backing into a single unit. Assembly with the outer shell requires only filling the lower part of the inner shell with an epoxy potting layer and the upper part with cushioning material. This design provides a more robust and airtight connection, further improving sensor sensitivity. Thirdly, the high-frequency sensor incorporates a conical section in the middle of the inner shell. Compared to existing designs that use limiting posts inside the shell, this simplifies the structure and facilitates the positioning of the piezoelectric vibrator, enabling sealing and fixing of the vibrator to the inner shell using adhesive backing. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of the structure of the high-frequency sensor for material identification according to this utility model.

[0010] The reference numerals in the figure are as follows: outer shell 1, stepped surface 11, inner shell 2, conical segment 21, piezoelectric vibrator 3, negative electrode solder joint 31, positive electrode solder joint 32, lead wire 33, positive electrode pin 34, negative electrode pin 35, matching layer 4, focusing surface 41, adhesive backing 5, epoxy potting layer 6, and shock-absorbing material 7. Detailed Implementation

[0011] The technical solution of this utility model will be clearly and completely described below through embodiments. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0012] like Figure 1 As shown, the high-frequency sensor for material identification of this utility model includes a shell 1, an inner shell 2, a piezoelectric vibrator 3, and a matching layer 4.

[0013] The outer shell 1 can be configured as a single-piece molded part consisting of two cylindrical sections. A stepped surface 11 is provided between the lower and upper cylindrical sections, and the inner diameter of the lower cylindrical section is smaller than that of the upper cylindrical section. The material of the outer shell 1 can be selected as a high-strength material as needed.

[0014] The inner shell 2 is a one-piece molded part, and a conical section 21 is provided in the middle of the inner shell 2. The lower inner diameter of the conical section 21 is larger than the upper inner diameter. The piezoelectric vibrator 3 is disposed inside the conical section 21 of the inner shell 2. A negative electrode solder joint 31 is provided on the upper end surface of the piezoelectric vibrator 3, and a positive electrode solder joint 32 is provided on the lower end surface of the piezoelectric vibrator 3. The positive electrode solder joint 32 and the negative electrode solder joint 31 are respectively connected to the corresponding positive electrode pin 34 and negative electrode pin 35 through the lead wire 33. Inside the inner shell 2, the piezoelectric vibrator 3 is provided with adhesive 5 below it. Inside the outer shell 1, the lower cavity of the outer shell 1 is filled with epoxy potting layer 6 below the inner shell 2. The matching layer 4 is disposed above the piezoelectric vibrator 3. The upper end surface of the matching layer 4 is provided with a focusing curved surface 41. The cavity above the stepped surface 11 and the upper outer wall of the outer shell 1 are filled with damping material 7. The positive electrode pin 34 and the negative electrode pin 35 extend through the epoxy potting layer 6 to the outside of the outer shell 1.

[0015] The focusing surface 41 is a concave surface, and its curvature can be adjusted as needed. With this setting, the ultrasonic wave emission is focused by the concave surface, resulting in a smaller ultrasonic angle. During detection, multiple echo reflections reduce the loss of sound wave energy, thereby improving the sensor's sensitivity without increasing residual vibration.

[0016] The matching layer 4, piezoelectric vibrator 3, adhesive backing 5, and inner shell 2 are integrally molded into an inner shell module. After the inner shell module is installed into the outer shell, the bottom is sealed by an epoxy potting layer 6, and the top is sealed by a shock-absorbing material 7. With this design, the matching layer 4, piezoelectric vibrator 3, adhesive backing 5, and inner shell 2 are molded as a whole, avoiding the need for the matching layer 4 to be molded separately. If the matching layer 4 were molded separately, a groove for the negative electrode solder point 31 on the upper part of the piezoelectric vibrator 3 would need to be reserved. It is difficult to make the size and position of the negative electrode solder point 31 of the piezoelectric vibrator 3 consistent, which would require the groove to have a margin relative to the negative electrode solder point 31. If the groove of the matching layer 4 is too large, some of the function of the matching layer 4 will be lost, reducing the sensitivity of the sensor.

[0017] In this invention, a high-frequency sensor for material identification is used such that the positive pin 34 and the negative pin 35 are connected to the corresponding circuit board and installed on a robotic vacuum cleaner. When the piezoelectric vibrator 3 is powered on, it emits a high-frequency ultrasonic signal to identify the material of objects encountered on the ground during the sweeping process, so as to clean according to the identified material.

[0018] This invention relates to a high-frequency sensor for material identification. A focusing surface is provided on the upper surface of the matching layer. This focusing surface design allows the ultrasonic waves emitted by the high-frequency sensor to be focused through the concave surface, resulting in a smaller ultrasonic angle. During multiple echo reflections during detection, less sound wave energy is lost, thus improving the sensor's sensitivity without increasing residual vibration. This avoids the superposition of residual vibration and multiple echo signals, ensuring the accuracy of material identification. The high-frequency sensor for material identification integrates the inner shell, matching layer, piezoelectric vibrator, and adhesive backing into a single unit. When assembling with the outer shell, only an epoxy potting layer needs to be filled at the bottom of the inner shell, and a cushioning material at the top of the outer shell. This design makes the overall connection of the high-frequency sensor more robust, provides better sealing, and improves the sensor's sensitivity. The high-frequency sensor for material identification also features a conical section in the middle of the inner shell. Compared to existing technologies that use limiting posts inside the shell, this simplifies the structure and facilitates the positioning of the piezoelectric vibrator, allowing for sealing and fixing of the piezoelectric vibrator to the inner shell using the adhesive backing.

[0019] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high frequency sensor for material identification, characterized in that The device includes an outer shell, an inner shell, a piezoelectric vibrator, and a matching layer. The inner shell has a conical section in the middle, with the lower inner diameter of the conical section being larger than the upper inner diameter. The piezoelectric vibrator is located inside the conical section of the inner shell. A negative electrode solder joint is located on the upper end face of the piezoelectric vibrator, and a positive electrode solder joint is located on the lower end face of the piezoelectric vibrator. The positive and negative electrode solder joints are connected to the corresponding positive and negative electrode pins via leads. Inside the inner shell, there is an adhesive backing below the piezoelectric vibrator. Inside the outer shell, the lower cavity of the outer shell is filled with an epoxy potting layer. The matching layer is located above the piezoelectric vibrator, and a focusing curved surface is located on the upper end face of the matching layer. A stepped surface is located on the upper part of the outer shell, with the upper radius of the stepped surface being larger than the lower radius. A damping material is filled between the cavity above the stepped surface and the upper outer wall of the outer shell. The positive and negative electrode pins extend through the epoxy potting layer to the outside of the outer shell.

2. The high frequency sensor for material identification according to claim 1, characterized in that: The focusing surface is a concave surface.

3. The high-frequency sensor for material identification according to claim 1, characterized in that: The matching layer, piezoelectric vibrator, adhesive backing, and inner shell are integrally formed into an inner shell module. After the inner shell module is installed into the outer shell, the bottom is filled and sealed by an epoxy potting layer, and the top is filled and sealed by a shock-absorbing material.

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