A pressure sensor and method for adaptively adjusting a lever arm

Abstract

The present invention discloses a pressure sensor and method for adaptively adjusting a lever arm, comprising a strain sensor, a drive unit, and a control unit. The strain sensor is located between a first flange plate and a second flange plate, with one end of the strain sensor bottom connected to the second flange plate and spaced apart. A strain gauge is provided on the side of the strain sensor. The top of the strain sensor is connected to the bottom of the first flange plate using a reciprocating screw structure, with the reciprocating direction being the length of the strain gauge. The drive unit is connected to the screw in the reciprocating screw structure. The control unit includes a data processing unit and a digital-to-analog conversion unit. The input end of the data processing unit is connected to the output end of the strain gauge, the data processing unit is connected to the digital-to-analog conversion unit, and the output end of the data processing unit is connected to the signal input end of the drive unit. The force arm of the pressure sensor can be changed, thereby controlling the range of the pressure sensor output signal and improving the sensitivity of the pressure sensor.

Description

Technical Field

[0001] The invention belongs to the field of pressure detection and relates to a pressure sensor and a method for adaptively adjusting a force arm. Background Art

[0002] As the market demand for pressure sensors increases, so do the requirements for them. Traditional pressure sensors measure pressure by measuring the deformation of elastic elements. However, due to the limitations of elasticity, the output signal pressure of the pressure sensor when subjected to pressure is usually within a fixed range and the sensitivity is fixed, which cannot meet the pressure measurement requirements in various application scenarios. Summary of the Invention

[0003] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a pressure sensor and method with adaptive adjustment of the lever arm, which can change the lever arm of the pressure sensor, thereby controlling the range of the pressure sensor output signal and improving the sensitivity of the pressure sensor.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A pressure sensor with an adaptively adjustable force arm comprises a first flange plate, a strain sensor, a second flange plate, a drive unit and a control unit;

[0006] The strain sensor is located between the first flange plate and the second flange plate. One end of the bottom of the strain sensor is connected to the second flange plate and the two are spaced apart. A strain gauge is provided on the side of the strain sensor. The top of the strain sensor is connected to the bottom of the first flange plate using a reciprocating screw structure. The reciprocating direction is the length direction of the strain gauge. The drive unit is connected to the screw in the reciprocating screw structure.

[0007] The control unit includes a data processing unit and a digital-to-analog conversion unit. The input end of the data processing unit is connected to the output end of the strain gauge, the data processing unit is connected to the digital-to-analog conversion unit, and the output end of the data processing unit is connected to the signal input end of the drive unit.

[0008] Preferably, the reciprocating screw structure includes a screw rod, a slider and a slide rail, the slide rail is located at the top of the strain sensor, the top of the slider is connected to the bottom of the first flange plate, the bottom of the slider is slidably connected to the slide rail, the screw rod is arranged outside the strain sensor, the end of the screw rod is connected to the drive unit, and the screw rod is threadedly connected to the slider, and the direction of the screw rod and the direction of the slide rail are both the length direction of the strain gauge.

[0009] Furthermore, the driving unit adopts an electric motor.

[0010] Furthermore, a screw flange plate is installed on the motor, the screw flange plate is fixed to the end of the strain sensor, the motor output shaft passes through the screw flange plate, and the free end of the motor output shaft is connected to the screw end using a coupling.

[0011] Furthermore, a first pad is provided between the first flange plate and the slider.

[0012] Furthermore, the top of the first cushion block is fixed to the first flange plate by screws, and the bottom of the first cushion block is fixed to the slider by screws.

[0013] Furthermore, a second gasket is provided between one end of the bottom of the strain sensor and the second flange plate.

[0014] Furthermore, the digital-to-analog conversion unit adopts an ADC module.

[0015] Furthermore, the data processing unit adopts MCU.

[0016] A method for adaptively adjusting the lever arm of the pressure sensor includes the following steps:

[0017] The object to be measured is placed on the first flange plate. The strain gauge collects the deformation of the object and transmits it to the data processing unit. The data processing unit calculates the analog signal generated by the current deformation. The digital-to-analog conversion unit converts the current output signal into a digital signal, which is the measured pressure data.

[0018] At the same time, the data processing unit calculates the signal-to-noise ratio of the current output signal and determines whether the current signal-to-noise ratio value is within a normal range. If the signal-to-noise ratio exceeds the set range, the data processing unit controls the drive unit to drive the reciprocating screw structure to move the first flange plate toward the fixed end of the strain sensor, thereby reducing the force arm of the pressure sensor until the signal-to-noise ratio reaches the set range.

[0019] If the signal-to-noise ratio is less than the set range, the data processing unit controls the drive unit to drive the reciprocating screw structure to move the first flange plate toward the loading end of the strain sensor, reducing the force arm of the pressure sensor until the signal-to-noise ratio reaches the set range.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] In this application, the top of the strain sensor is connected to the bottom of the first flange plate through a reciprocating screw structure, and the driving unit is connected to the screw in the reciprocating screw structure. The driving unit drives the reciprocating screw structure to move the first flange plate back and forth between the loading end and the fixed end on the strain sensor, thereby adjusting the force arm size of the pressure sensor. The strain gauge collects the deformation variable generated by the current object and transmits it to the data processing unit. The data processing unit calculates the analog signal generated by the current deformation variable, and the digital-to-analog conversion unit converts the current output signal into a digital signal, which is the measured pressure data; at the same time, the signal-to-noise ratio of the current output signal is calculated by the data processing unit, and it is determined whether the current signal-to-noise ratio value is within the normal range. If the signal-to-noise ratio is large, it will cause signal distortion and affect the measurement accuracy of the pressure sensor. It is necessary to change the signal-to-noise ratio of the pressure sensor by reducing the force arm of the pressure sensor. If the signal-to-noise ratio is small, the noise interference is too large, and it is necessary to increase the force arm of the pressure sensor to enhance the signal, thereby changing the output signal and improving the sensitivity of the pressure sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a front view of the pressure sensor structure with an adaptively adjustable lever arm according to the present invention;

[0023] Figure 2 This is a rear view of the pressure sensor structure of the adaptive adjustment lever arm of the present invention;

[0024] Figure 3 Schematic diagram of the internal structure of the control unit of the present invention;

[0025] Figure 4 It is a structural schematic diagram of the pressure sensor adjustment process of the present invention;

[0026] Figure 5 FIG. 1 is a schematic diagram of the internal principle of the strain gauge 5 of the pressure sensor of the present invention during movement.

[0027] 1-first flange plate, 2-slider, 3-slide rail, 4-strain sensor, 5-strain gauge, 6-second flange plate, 7-first cushion block, 8-second cushion block, 9-motor, 10-screw flange plate, 11-control unit, 12-ADC module, 13-MCU. DETAILED DESCRIPTION

[0028] The embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and are not to be construed as limiting the present invention.

[0029] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like, indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present invention pertains. The terms "installed", "connected", and "connected" should be understood in a broad sense, for example, they can be fixedly connected, detachably connected, or integrally connected; they can be mechanically connected, electrically connected, or able to communicate with each other; they can be directly connected, or indirectly connected through an intermediate medium, or they can be internally connected between two elements or an interactive relationship between two elements. The term "and / or" used herein includes any and all combinations of one or more related listed items. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0031] The disclosure below provides many different embodiments or examples for realizing different structures of the present invention. In order to simplify the disclosure of the present invention, the components and settings of specific examples are described below. Of course, they are merely examples and are not intended to limit the present invention. In addition, the present invention may repeat reference numbers and / or reference letters in different examples. Such repetition is for the purpose of simplicity and clarity and does not in itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present invention provides examples of various specific processes and materials, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0032] The embodiment of the present application provides a schematic diagram of the structure of a pressure sensor for adaptively adjusting the lever arm, as shown in FIG. Figure 1 、 Figure 2Shown are the front and rear views of a pressure sensor with an adaptively adjustable force arm. The pressure sensor mainly includes: a first flange plate 1, a slider 2, a slide rail 3, a strain sensor 4, a strain gauge 5, a second flange plate 6 and a drive structure.

[0033] The strain gauge 5 is attached to the side of the strain sensor 4 by adhesive bonding. A groove is provided in the strain sensor 4 corresponding to the strain gauge 5 , and the strain gauge 5 is arranged in the groove.

[0034] The slide rail 3 is mounted on top of the strain sensor 4 and fixed with screws. The slider 2 is slidably connected to the top of the slide rail 3. The first flange plate 1 and the second flange plate 6 are respectively mounted above and below the strain sensor 4 to place the object to be measured.

[0035] A pad is provided in the pressure sensor for buffering the pressure when measuring an object, including a first pad 7 and a second pad 8. The first pad 7 is located between the first flange plate 1 and the slider 2. The top of the first pad 7 is fixed to the first flange plate 1 by screws, and the bottom is fixed to the slider 2 by screws. According to the above-mentioned fixed structure, the first flange plate 1, the first pad 7 and the slider 2 are connected as a whole. Since the slider 2 is slidably connected above the slide rail 3, the whole can be adjusted and moved through the slide rail 3. The position of the slider 2 on the strain sensor 4 is the loading end of the strain sensor 4.

[0036] The second pad 8 is located between the second flange plate 6 and the strain sensor 4, wherein the top screw of the second flange plate 6 is fixed to the bottom of the second pad 8, and the top of the second pad 8 is fixed to the bottom of one end of the strain sensor 4. This connection position serves as the fixed end of the strain sensor 4, and the top of the strain sensor 4 is fixedly connected to the slide rail 3. According to the above-mentioned fixed structure, the second flange plate 6, the second pad 8, the strain sensor 4 and the slide rail 3 are connected as one.

[0037] The drive structure includes a drive unit and a control unit 11. In this embodiment, the drive unit is a motor 9, which is used to control the movement of the slider 2 on the slide rail 3. The control unit 11 is connected to the motor 9, which is equipped with a screw flange plate 10. The screw flange plate 10 is fixed to the end of the strain sensor 4 and is not connected to the first flange plate 1, the first cushion block 7, and the slider 2. The output shaft of the motor 9 passes through the screw flange plate 10. The free end of the motor 9 output shaft is connected to a screw through a coupling. The screw is arranged outside the strain sensor 4 and is threadedly connected to the slider 2. The direction of the screw is consistent with the direction of the slide rail 3. The screw, slider 2, and slide rail 3 form a reciprocating screw structure. The rotation of the motor 9 controls the linear movement of the slider 2 along the slide rail 3, thereby changing the position of the slider 2 on top of the strain sensor 4.

[0038] like Figure 3The figure shows the internal schematic diagram of the control unit 11. The control unit 11 includes a data processing unit and a digital-to-analog conversion unit. The digital-to-analog conversion unit is an ADC module 12 (Analog-to-digital converter) module, which is used to convert the analog output signal of the pressure sensor when it is subjected to pressure into a digital signal. In this embodiment, the data processing unit is an MCU 13 (Microcontroller Unit), which can also be a microcontroller, etc., and is not specifically limited in this embodiment. The input end of MCU 13 is connected to the output end of strain gauge 5, and MCU 13 is connected to ADC module 12. The output end of MCU 13 is connected to the signal input end of motor 9. MCU 13 is used to control the movement of motor 9 and also processes the output signal of the pressure sensor to adaptively adjust the force arm.

[0039] According to the above-mentioned embodiment, a pressure sensor with an adaptively adjustable lever arm is proposed. The specific implementation principle includes the following steps: an object to be measured is placed on the first flange plate 1 of the pressure sensor, a strain gauge 5 collects the deformation generated by the current object and transmits it to the control unit 11, an MCU 13 in the control unit 11 calculates the analog signal generated by the current deformation, and an ADC module 12 converts the current output signal into a digital signal, which is the measured pressure data. Simultaneously, the MCU 13 calculates the signal-to-noise ratio of the current output signal, which is the ratio of signal to noise. It also determines whether the current signal-to-noise ratio value is within a normal range. If the signal-to-noise ratio is large and exceeds the set range, it will cause signal distortion and affect the measurement accuracy of the pressure sensor. It is necessary to change the signal-to-noise ratio of the pressure sensor by reducing the lever arm of the pressure sensor. The MCU 13 controls the rotation of the motor 9, which drives the slider 2 along the slide rail 3 toward the fixed end of the strain sensor 4 through the screw until the signal-to-noise ratio reaches the set range.

[0040] If the signal-to-noise ratio is low, outside the set range, then the noise interference is excessive, and the pressure sensor's lever arm needs to be increased to enhance the signal, thereby changing the output signal and improving the pressure sensor's sensitivity. At this point, MCU 13 controls motor 9 to rotate, driving slider 2 along rail 3 via the lead screw toward the opposite end of the fixed end of strain sensor 4 until the signal-to-noise ratio reaches the set range.

[0041] According to the above working principle, when the signal-to-noise ratio of the pressure sensor is not within the normal range, the force arm of the pressure sensor needs to be adjusted. The specific adjustment process includes: controlling the motor 9 through the MCU13 in the control unit 11, and the motor 9 controls the movement of the slider 2. In this embodiment, the movement of the slider 2 will cause the force arm to change, thereby changing the signal-to-noise ratio of the pressure sensor when the same object is subjected to force, adjusting the output signal, and thereby improving the sensitivity of the pressure sensor during operation.

[0042] According to the working principle of the pressure sensor in the above embodiment, Figure 4 The figure shows the structure of the sensor movement process. The motor 9 drives the slider 2, the first flange plate 1, and the first pad 7 to move along the slide rail 3. Figure 3 The current position shown, the force arm of the pressure sensor changes.

[0043] In this embodiment, move to Figure 4 When the position is Figure 5 The figure shows a schematic diagram of the specific internal principle of the strain gauge 5. The length of the strain gauge 5 of the pressure sensor is L, that is, when the pressure sensor slider 2 is in the initial position, the length of the strain gauge 5 is the force arm L1. When a pressure F is applied to the pressure sensor, the deformation variable X1 of the strain gauge 5 caused by F is L1tanα, where α is the angle between the strain gauge 5 before and after the deformation when the force arm length is L1. The voltage value V1 output by the pressure sensor under the current deformation can be obtained. The slider 2 is moved from the original position by ΔL by the motor 9. At this time, the force arm length of the strain gauge 5 is L2, L2=L1-ΔL. Then a force F of the same magnitude is applied to the pressure sensor. At this time, the deformation variable X2 of the strain gauge 5 caused by F is L2tanβ, where β is the angle between the strain gauge 5 before and after the deformation when the force arm length is L2. The voltage value V2 output by the pressure sensor under the current deformation can be obtained.

[0044] According to the lever principle, if the same equilibrium condition needs to be achieved, the vector product of the two forces and their lever arms should be the same according to the formula F×L1=F×L2. If the deformation of the strain gauge 5 is required to be the same, then when the slider 2 moves and the lever arm decreases, a larger force must be applied. In the above embodiment, the two applied forces are both F, but the lever arm length L1>L2, which means X1>X2, that is, the deformation under the same force decreases after the slide rail 3 moves, so V1≠V 2， Therefore, when the same force is applied twice, the voltage signal transmitted by the pressure sensor in this application is different. That is, the output signal is different after adjusting the lever arm, thus achieving the purpose of changing the output signal range of the pressure sensor by adjusting the lever arm.

[0045] To sum up, the adaptively adjustable pressure sensor proposed in this application controls the motor 9 to drive the slider 2 to move, thereby changing the force arm of the pressure sensor when the pressure sensor is subjected to the same pressure, thereby changing the range of the pressure sensor output signal and improving the sensitivity of the pressure sensor.

[0046] The present application proposes a pressure sensor with an adaptively adjustable force arm, wherein the strain gauge 5 is glued into the strain sensor 4; the slide rail 2 and the strain sensor 4 are fixed by screws; the slider 2 is located above the slide rail 3; a drive unit is installed on the slider 2, and the movement of the slider 2 on the slide rail 3 is controlled by the drive unit. When the pressure sensor is subjected to pressure, the digital-to-analog conversion unit is used to convert the analog signal output by the pressure sensor into a digital signal, and the data processing unit is used to control the drive unit and process the pressure sensor data, and adaptively change the force arm of the pressure sensor according to the signal output by the pressure sensor, thereby controlling the range of the pressure sensor output signal and improving the sensitivity of the pressure sensor.

[0047] The serial numbers of the above embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0048] In the above embodiments of the present application, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, please refer to the relevant description of other embodiments.

[0049] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only exemplary. For example, the division of the units can be a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0050] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0051] The above is only a preferred embodiment of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

[0052] It should be understood that the above description is for illustration and not for limitation. Many embodiments and many applications beyond the examples provided will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of this patent should not be determined with reference to the above description, but rather with reference to the preceding claims and the full scope of equivalents to which such claims are entitled. For the purpose of completeness, all articles and references, including disclosures of patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein from the preceding claims is not a disclaimer of such subject matter, nor should it be considered that the applicants did not consider such subject matter to be part of the disclosed inventive subject matter.

Claims

1. A pressure sensor with an adaptively adjustable lever arm, characterized in that: It comprises a first flange plate (1), a strain sensor (4), a second flange plate (6), a drive unit and a control unit (11); The strain sensor (4) is located between the first flange plate (1) and the second flange plate (6), one end of the bottom of the strain sensor (4) is connected to the second flange plate (6) and is arranged at intervals, a strain gauge (5) is arranged on the side of the strain sensor (4), the top of the strain sensor (4) is connected to the bottom of the first flange plate (1) by a reciprocating screw structure, the reciprocating direction is the length direction of the strain gauge (5), and the drive unit is connected to the screw in the reciprocating screw structure; The control unit (11) includes a data processing unit and a digital-to-analog conversion unit, wherein the input end of the data processing unit is connected to the output end of the strain gauge (5), the data processing unit is connected to the digital-to-analog conversion unit, and the output end of the data processing unit is connected to the signal input end of the drive unit.

2. The pressure sensor with adaptive adjustment of the lever arm according to claim 1, characterized in that: The reciprocating screw structure includes a screw, a slider (2) and a slide rail (3), the slide rail (3) is located at the top of the strain sensor (4), the top of the slider (2) is connected to the bottom of the first flange plate (1), the bottom of the slider (2) is slidably connected to the slide rail (3), the screw is arranged outside the strain sensor (4), the end of the screw is connected to the drive unit, and the screw is threadedly connected to the slider (2), and the direction of the screw and the direction of the slide rail (3) are both the length direction of the strain gauge (5).

3. The pressure sensor with adaptive adjustment of the lever arm according to claim 2, characterized in that: The driving unit adopts a motor (9).

4. The pressure sensor with adaptively adjustable lever arm according to claim 3, characterized in that: A screw flange plate (10) is installed on the motor (9), the screw flange plate (10) is fixed to the end of the strain sensor (4), the output shaft of the motor (9) passes through the screw flange plate (10), and the free end of the output shaft of the motor (9) is connected to the end of the screw by a coupling.

5. The pressure sensor with adaptively adjustable lever arm according to claim 2, characterized in that: A first cushion block (7) is provided between the first flange plate (1) and the slider (2).

6. The pressure sensor with adaptively adjustable lever arm according to claim 5, characterized in that: The top of the first pad (7) is fixed to the first flange plate (1) by screws, and the bottom is fixed to the slider (2) by screws.

7. The pressure sensor with adaptively adjustable lever arm according to claim 1, characterized in that: A second cushion block (8) is provided between one end of the bottom of the strain sensor (4) and the second flange plate (6).

8. The pressure sensor with adaptively adjustable lever arm according to claim 1, characterized in that: The digital-to-analog conversion unit adopts an ADC module (12).

9. The pressure sensor with adaptively adjustable lever arm according to claim 1, characterized in that: The data processing unit adopts MCU (13).

10. A method for adaptively adjusting the lever arm of a pressure sensor according to any one of claims 1 to 9, characterized in that: The following processes are included: The object to be measured is placed on the first flange plate (1), and the strain gauge (5) collects the deformation variable generated by the current object and transmits it to the data processing unit. The data processing unit calculates the analog signal generated by the current deformation variable, and the digital-to-analog conversion unit converts the current output signal into a digital signal, which is the measured pressure data; At the same time, the data processing unit calculates the signal-to-noise ratio of the current output signal and determines whether the value of the current signal-to-noise ratio is within a normal range. If the signal-to-noise ratio exceeds the set range, the data processing unit controls the drive unit to drive the reciprocating screw structure to move the first flange plate (1) toward the fixed end of the strain sensor (4), thereby reducing the force arm of the pressure sensor until the signal-to-noise ratio reaches within the set range. If the signal-to-noise ratio is less than the set range, the data processing unit controls the drive unit to drive the reciprocating screw structure to move the first flange plate (1) toward the loading end of the strain sensor (4), thereby reducing the force arm of the pressure sensor until the signal-to-noise ratio reaches the set range.

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