Knock sensor

Abstract

The utility model discloses a knock sensor, which belongs to the technical field of sensors and comprises a shell, a knock sensor core, a knock sensor core and a knock sensor core, the piezoelectric film is arranged in the accommodating cavity; the PCBA board is limited in the accommodating cavity, and the PCBA board is used for pressing the piezoelectric film on the bottom surface of the accommodating cavity, so that the piezoelectric film is attached to the bottom surface of the accommodating cavity; the piezoelectric film is configured to generate piezoelectric signals according to vibration of the shell, the PCBA board is electrically connected with the piezoelectric film, the PCBA board is configured to process the piezoelectric signals to generate detection signals and transmit the detection signals, and the knocking sensor has the advantages of being high in sensitivity and accuracy.

Description

Technical Field

[0001] This utility model relates to the field of sensor technology, and in particular to a tapping sensor. Background Technology

[0002] Current electrical appliances are typically controlled via buttons. When a user presses a button, the button sends a signal to the appliance, which then performs the corresponding action. However, with the continuous upgrading and improvement of electrical appliances, the function of controlling appliances by tapping them has gradually emerged. Therefore, how to detect the vibration signal when appliances are tapped is a technical problem that urgently needs to be solved. Utility Model Content

[0003] The purpose of this invention is to provide a tapping sensor to solve the above-mentioned problems.

[0004] To achieve this objective, the present invention adopts the following technical solution:

[0005] A tap sensor, comprising:

[0006] A housing, the interior of which is formed a cavity;

[0007] A piezoelectric thin film, wherein the piezoelectric thin film is disposed within the cavity;

[0008] PCBA board, wherein the PCBA board is confined within the cavity, and the PCBA board presses the piezoelectric film onto the bottom surface of the cavity so that the piezoelectric film is in contact with the bottom surface of the cavity;

[0009] The piezoelectric film is configured to generate a piezoelectric signal based on the vibration of the housing. The PCBA board is electrically connected to the piezoelectric film and is configured to process the piezoelectric signal to generate a detection signal and transmit the detection signal.

[0010] Preferably, the inner wall of the cavity is provided with multiple retaining teeth, which together restrict the PCBA board within the cavity.

[0011] Preferably, the bottom of the cavity is provided with a vibration relief groove, which corresponds to a portion of the piezoelectric film.

[0012] Preferably, one end of the piezoelectric film is provided with a pin, and the piezoelectric film is electrically connected to the PCBA board through the pin. The pin is bent downward and forms a certain angle with the PCBA board. The PCBA board applies force to the pin to press the piezoelectric film onto the bottom surface of the cavity.

[0013] Preferably, the PCBA board is provided with a signal transmission module, through which the PCBA board transmits the detection signal to external electrical equipment.

[0014] Preferably, the housing has a connecting portion on at least one side, and the housing is fixed to an external electrical device through the connecting portion.

[0015] Preferably, the PCBA board has asymmetrical notches, and the cavity is provided with limiting strips that correspond one-to-one with the notches.

[0016] Preferably, the device further includes a potting compound used to fix the PCBA board and the piezoelectric film within the cavity.

[0017] Preferably, the signal transmission module is a terminal block.

[0018] Preferably, the angle between the pin and the PCBA board is 1° to 20°.

[0019] One embodiment of this utility model has the following beneficial effects:

[0020] 1. When external vibrations are transmitted to the housing, since the piezoelectric film is in contact with the bottom surface of the cavity, the vibration of the housing is transmitted to the piezoelectric film through the bottom surface of the cavity. When the piezoelectric film vibrates, it generates a piezoelectric signal. The PCBA board processes the electrical signal into a detection signal and transmits the detection signal outward.

[0021] 2. By pressing the piezoelectric film onto the bottom surface of the cavity through the PCBA board, the structure of the impact sensor can be made more compact and the overall size smaller, which is beneficial to the space utilization of electrical equipment. In addition, the piezoelectric film can be directly soldered onto the PCBA board, thereby reducing the use of wires and lowering costs. Furthermore, since the piezoelectric film is directly connected to the PCBA board, the signal transmission distance is reduced, resulting in less signal interference and loss.

[0022] 3. By placing both the piezoelectric film and the PCBA board within the cavity of the housing, the impact sensor is integrated into a single unit, making installation more convenient. Attached Figure Description

[0023] The accompanying drawings further illustrate the present invention, but the content of the drawings does not constitute any limitation on the present invention.

[0024] Figure 1 This is a three-dimensional structural diagram of one embodiment of the present utility model;

[0025] Figure 2 This is a cross-sectional structural schematic diagram of one embodiment of the present invention;

[0026] Figure 3 This is a front view schematic diagram of the connection between the piezoelectric film and the PCBA board according to one embodiment of the present invention;

[0027] Figure 4 This is a bottom view schematic diagram of the connection between the piezoelectric film and the PCBA board in one embodiment of this utility model;

[0028] Figure 5 This is a three-dimensional structural diagram of the housing according to one embodiment of the present utility model;

[0029] In the attached diagram: 1-housing, 11-cavity, 12-tooth, 13-vibration clearance groove, 14-connecting part, 15-limiting strip, 2-piezoelectric film, 21-pin, 3-PCBA board, 31-notch, 32-terminal. Detailed Implementation

[0030] The embodiments of this utility model are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model. In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting this utility model. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this utility model, "multiple" means two or more, unless otherwise explicitly specified.

[0031] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows for communication; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0032] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0033] The following disclosure provides many different embodiments or examples for implementing various structures of this invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of the invention. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, examples of various specific processes and materials are provided in this invention, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0034] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.

[0035] One type of tapping sensor in this embodiment, such as Figure 1-5 As shown, it includes:

[0036] The housing 1 has a cavity 11 formed inside it;

[0037] A piezoelectric film 2 is disposed within the cavity 11;

[0038] PCBA board 3, the PCBA board 3 is confined within the cavity 11, and the PCBA board 3 presses the piezoelectric film 2 against the bottom surface of the cavity 11 so that the piezoelectric film 2 is in contact with the bottom surface of the cavity 11;

[0039] The piezoelectric film 2 is configured to generate a piezoelectric signal based on the vibration of the housing 1. The PCBA board 3 is electrically connected to the piezoelectric film 2, and the PCBA board 3 is configured to process the piezoelectric signal to generate a detection signal and transmit the detection signal.

[0040] In practical use, the tapping sensor of this invention is installed on the inner wall of the tapping area of ​​the electrical appliance, such as the inner wall of the appliance's panel or the inner wall of its casing. The specific installation location depends on the specific appliance and the function to be achieved. Taking a built-in dishwasher as an example, in order to achieve a better overall effect with the cabinet, the built-in dishwasher can eliminate the door handle. When the panel of the built-in dishwasher is tapped, the door panel is automatically pushed out at a certain angle. Therefore, it is necessary to detect the tapping signal at the panel of the built-in dishwasher. Thus, the tapping sensor can be fixed to the inner wall of the panel of the built-in dishwasher. When the panel of the built-in dishwasher is tapped, the vibration of the panel is transmitted to the housing 1 of the tapping sensor, thereby accurately detecting the tapping signal of the panel. Embodiments of this invention applied to other electrical appliances are not described in detail.

[0041] When external vibrations are transmitted to the housing 1, since the piezoelectric film 2 is in contact with the bottom surface of the cavity 11, the vibration of the housing 1 is transmitted to the piezoelectric film 2 through the bottom surface of the cavity 11. When the piezoelectric film 2 vibrates, it generates a piezoelectric signal. The PCBA board 3 processes the electrical signal into a detection signal and transmits the detection signal outward. For example, the PCBA board 3 actively sends the detection signal to an external electrical device, or the external electrical device actively acquires the detection signal from the PCBA. In this invention, the piezoelectric film 2 is pressed into the cavity 11 by the PCBA board 3. The bottom surface of the device allows for a more compact structure and smaller overall size of the impact sensor, which is beneficial for space utilization in electrical equipment. In addition, the piezoelectric film 2 can be directly soldered onto the PCBA board 3, thereby reducing the use of wires and lowering costs. Furthermore, since the piezoelectric film 2 and the PCBA board 3 are directly connected, the signal transmission distance is reduced, resulting in less signal interference and loss. Moreover, this invention places both the piezoelectric film 2 and the PCBA board 3 within the cavity 11 of the housing 1, making the impact sensor an integrated structure that is more convenient to install.

[0042] Furthermore, the inner wall of the cavity 11 is provided with a plurality of retaining teeth 12, which together restrict the PCBA board 3 within the cavity 11.

[0043] With this setup, multiple locking teeth 12 can be used to clamp the PCBA board 3 into the cavity 11, so that the PCBA board 3 can be firmly fixed in the cavity 11 and is not easy to loosen. It can also effectively press the piezoelectric film 2 onto the bottom surface of the cavity 11, preventing the piezoelectric film 2 from detaching from the bottom surface of the cavity 11 and affecting the accuracy of the detection.

[0044] Furthermore, the bottom of the cavity 11 is provided with a vibration relief groove 13, which corresponds to a portion of the piezoelectric film 2.

[0045] By setting a relief groove, part of the piezoelectric film 2 can be suspended in the relief groove, while the other part is attached to the bottom surface of the cavity 11. This allows the vibration of the housing 1 to be transmitted to the piezoelectric film 2 through the bottom surface of the cavity 11, so that the piezoelectric film 2 generates a piezoelectric signal. At the same time, it prevents the piezoelectric film 2 from being completely compressed and unable to respond to the vibration of the housing 1, thereby enabling more accurate detection of vibrations caused by knocking.

[0046] Furthermore, one end of the piezoelectric film 2 is provided with a pin 21, and the piezoelectric film 2 is electrically connected to the PCBA board 3 through the pin 21. The pin 21 is bent downward and forms a certain angle with the PCBA board 3. The PCBA board 3 applies force to the pin 21 to press the piezoelectric film 2 onto the bottom surface of the cavity 11.

[0047] The bottom surface of the PCBA board 3 has pads corresponding to the pins 21. The piezoelectric film 2 is soldered to the corresponding pads through the pins 21, thereby achieving electrical and mechanical connection with the PCBA board 3. At this time, the piezoelectric film 2 can not only transmit electrical signals with the PCBA board 3, but also form a certain mechanical connection structure. It should be noted that the pins 21 have a certain bending angle. When the PCBA board 3 is installed in the cavity 11, the pins 21 can be supported on the bottom surface of the cavity 11, and the PCBA board 3 applies downward pressure to the pins 21, thereby pressing the piezoelectric film 2 against the bottom surface of the cavity 11, so that the piezoelectric film 2 is in contact with the bottom surface of the cavity 11. This can effectively solve the problem that the bottom surface of the PCBA board 3 directly presses the piezoelectric film 2 too tightly or the piezoelectric film 2 cannot be fully in contact with the bottom surface of the cavity 11, thus affecting the detection accuracy. Understandably, the piezoelectric film 2 needs to generate piezoelectricity through deformation. Signals, such as bending, are highly sensitive to the piezoelectric film 2. Due to the certain processing error in the thickness of the PCBA board 3, if the thickness of the PCBA board 3 is too large, the piezoelectric film 2 will be firmly pressed against the bottom surface of the cavity 11, which will cause the piezoelectric film 2 to lose the space for deformation, thereby greatly reducing the accuracy of detection, or even making it impossible to detect the vibration generated by the knock. Similarly, if the PCBA board 3 is too thin, the piezoelectric film 2 may not be able to fully adhere to the bottom surface of the cavity 11, thus making it difficult to respond to the vibration of the shell 1, and the detection sensitivity of the vibration signal will be greatly reduced. Therefore, this utility model cleverly bends the pin 21 of the piezoelectric film 2 at a certain angle, and applies force to the pin 21 through the PCBA board 3. The elasticity of the pin 21 is used to press the piezoelectric film 2 against the bottom surface of the cavity 11. The pin 21 can absorb the processing error of the PCBA board 3, thereby making it sensitive and accurate in responding to the vibration of the shell 1.

[0048] Furthermore, the PCBA board 3 is provided with a signal transmission module, through which the PCBA board 3 transmits the detection signal to external electrical equipment.

[0049] The signal transmission module enables communication between PCBA board 3 and external electrical devices, thereby transmitting detection signals to the external electrical devices. The signal transmission module can be any module capable of transmitting signal data, such as Bluetooth module, infrared module, NFC module, terminal block 32, Zigbee module, or WIFI module, etc.

[0050] Furthermore, the housing 1 has a connecting portion 14 on at least one side, and the housing 1 is fixed to an external electrical device through the connecting portion 14.

[0051] During installation, the connecting part 14 is mechanically connected to the external electrical device by means of screws, rivets, welding, etc. This not only fixes the impact sensor, but also makes the fixed connection a rigid connection, which can effectively transmit the vibration generated when the electrical device is hit to the housing 1, thereby enabling more sensitive and accurate detection of the impact action on the electrical device.

[0052] Furthermore, the PCBA board 3 is provided with an asymmetrical notch 31, and the cavity 11 is provided with a limiting strip 15 corresponding to the notch 31.

[0053] This design helps prevent mistaken installation of the PCBA board 3 into the cavity 11.

[0054] Furthermore, it also includes a potting compound used to fix the PCBA board 3 and the piezoelectric film 2 within the cavity 11.

[0055] Encapsulating adhesive can provide better fixation, prevent PCBA board 3 from loosening, and also provide excellent sealing effect, thus providing dustproof, moisture-proof and corrosion-proof effects.

[0056] Furthermore, the signal transmission module is a terminal block 32.

[0057] Using terminal block 32 can simultaneously power PCBA board 3 and transmit signals.

[0058] Furthermore, the angle between the pin 21 and the PCBA board 3 is 1° to 20°.

[0059] When the pin 21 is made of different materials, its elasticity is different. The bending angle of the pin 21 can be set according to the specific material. It can be understood that when the angle between the pin 21 and the PCBA board 3 is less than 1°, the pin 21 is difficult to press the piezoelectric film 2 onto the bottom surface of the cavity 11 due to the small angle. When the angle between the pin 21 and the PCBA board 3 is greater than 20°, the bending angle is too large, which will generate greater stress on the solder joint between the pin 21 and the PCBA board 3, which is easy to cause desoldering. Preferably, the angle between the pin 21 and the PCBA board 3 is 3° to 10°.

[0060] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of this utility model. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0061] The technical principles of this utility model have been described above with reference to specific embodiments. These descriptions are merely for explaining the principles of this utility model and should not be construed as limiting the scope of protection of this utility model in any way. Based on this explanation, those skilled in the art can readily conceive of other specific embodiments of this utility model without inventive effort, and these equivalent modifications or substitutions are all included within the scope defined by the claims of this application.

Claims

1. A tapping sensor, characterized in that, include: A housing, the interior of which is formed a cavity; A piezoelectric thin film, wherein the piezoelectric thin film is disposed within the cavity; PCBA board, wherein the PCBA board is confined within the cavity, and the PCBA board presses the piezoelectric film onto the bottom surface of the cavity so that the piezoelectric film is in contact with the bottom surface of the cavity; The piezoelectric film is configured to generate a piezoelectric signal based on the vibration of the housing. The PCBA board is electrically connected to the piezoelectric film and is configured to process the piezoelectric signal to generate a detection signal and transmit the detection signal.

2. The tapping sensor according to claim 1, characterized in that, The inner wall of the cavity is provided with multiple retaining teeth, which together restrict the PCBA board within the cavity.

3. The tapping sensor according to claim 1, characterized in that, The bottom of the cavity is provided with a vibration relief groove, which corresponds to a portion of the piezoelectric film.

4. A tapping sensor according to claim 1, characterized in that, One end of the piezoelectric film is provided with a pin, and the piezoelectric film is electrically connected to the PCBA board through the pin. The pin is bent downward and forms a certain angle with the PCBA board. The PCBA board applies force to the pin to press the piezoelectric film onto the bottom surface of the cavity.

5. A tapping sensor according to claim 1, characterized in that, The PCBA board is equipped with a signal transmission module, through which the detection signal is transmitted to external electrical equipment.

6. A tapping sensor according to claim 1, characterized in that, The housing has a connecting portion on at least one side, and the housing is fixed to an external electrical device through the connecting portion.

7. A tapping sensor according to claim 1, characterized in that, The PCBA board has asymmetrical notches, and the cavity is provided with limiting strips that correspond one-to-one with the notches.

8. A tapping sensor according to claim 1, characterized in that, It also includes a potting compound used to fix the PCBA board and the piezoelectric film within the cavity.

9. A tapping sensor according to claim 5, characterized in that, The signal transmission module is a terminal block.

10. A tapping sensor according to claim 4, characterized in that, The angle between the pin and the PCBA board is 1° to 20°.

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