A self-resetting linear displacement sensor with wake-up function

Abstract

The embodiment of the present invention discloses a self-resetting linear displacement sensor with a wake-up function. The sensor includes: a structural housing, a magnetic moving shaft assembly, a reset spring, a limit cap, a fixing screw and a circuit board; wherein the reset spring is sleeved on the outside of the structural housing and the magnetic moving shaft assembly; the magnetic moving shaft assembly is slidably installed inside the structural housing; the limit cap is installed on the magnetic moving shaft assembly through a fixing screw, so that the reset spring is subjected to a pre-tightening force; the circuit board is installed at the bottom of the structural housing; the magnetic moving shaft assembly includes a magnet, and the circuit board includes a magnetoresistive chip and a micro-control unit, and the magnetoresistive chip is used to output a measurement signal to the micro-control unit according to the relative position with the magnet, so that the micro-control unit calculates the displacement change of the limit cap according to the measurement signal. Thus, the function of automatic reset is realized, and at the same time, the overall installation and measurement are convenient, the volume is small, and it is easy to operate, which can meet the displacement detection needs of small-volume structures.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of displacement detection technology, and in particular to a self-resetting linear displacement sensor with a wake-up function. Background Art

[0002] Most displacement sensors on the market currently use a winding moving iron core to change the magnetic resistance. Some use a special process to apply DAP resistor slurry on an insulator, heat it to polymerize it into a resistor film, or hot-press DAP resistor powder into a solid body formed in a groove of an insulating substrate as a resistor. However, no matter which method is used, the test position is reset by relying on the external structure of the sensor, and the initial test position cannot be automatically restored. In addition, the existing product structure is large in size, high in cost, complex in installation structure, and has high requirements for installation accuracy. At the same time, there is no sleep and wake-up mode, and it cannot be applied to battery-powered applications. Summary of the invention

[0003] The embodiment of the present invention provides a self-resetting linear displacement sensor with a wake-up function to solve the problems of displacement sensors currently on the market being large in size, complex to install, the displacement measurement axis having to be passively fixed, being unable to automatically reset, and being unable to use battery power.

[0004] The embodiment of the present invention provides a self-resetting linear displacement sensor with a wake-up function, the sensor comprising: a structural housing, a magnetic moving shaft assembly, a reset spring, a limit cap, a fixing screw and a circuit board; wherein,

[0005] The reset spring is sleeved on the outside of the structural housing and the magnetic movable shaft assembly; the magnetic movable shaft assembly is slidably mounted inside the structural housing; the limit cap is mounted on the magnetic movable shaft assembly through the fixing screw, so that the reset spring is subjected to a pre-tightening force; the circuit board is mounted on the bottom of the structural housing;

[0006] The magnetic movable axis assembly includes a magnet, and the circuit board includes a magnetoresistive chip and a microcontroller unit. The magnetoresistive chip is used to output a measurement signal to the microcontroller unit according to its relative position with the magnet, so that the microcontroller unit calculates the displacement change of the limit cap according to the measurement signal.

[0007] Optionally, the magnetic movable axis assembly further includes a sliding positioning structure, the interior of the structural shell includes a sliding structure groove, and the sliding positioning structure and the sliding structure groove are suitably slidably matched.

[0008] Optionally, the micro control unit is used to perform nonlinear calibration and temperature compensation on the measurement signal to calculate the displacement change.

[0009] Optionally, the micro control unit is used to control the stop of power supply to the magnetoresistive chip if the sensor is in a zero position state for more than a preset time, so as to put the sensor into a sleep state.

[0010] Optionally, the structural housing includes two electrically conductive connecting pins connected to the circuit board, the electrically conductive connecting pins include a short-circuit point, the magnetic movable axis assembly also includes a short-circuit wake-up structure, and the microcontroller unit is also used for when the sensor is in a sleep state, if the magnetic movable axis assembly is moved by an external force, so that the two ends of the short-circuit wake-up structure are respectively connected to the two short-circuit points to form a short-circuit switch signal, then the power supply of the magnetoresistive chip is restored to enable the sensor to enter a working state.

[0011] Optionally, the short-circuit wake-up structure includes a short-circuit support spring, and two sliding steel balls connected to both ends of the short-circuit support spring, and the short-circuit point specifically forms the short-circuit switch signal through the sliding steel balls.

[0012] Optionally, the circuit board further includes two short-circuit electrical connection points, which are respectively used to connect to the two electrical conduction connection pins to transmit the short-circuit switch signal to the micro control unit.

[0013] Optionally, the preset duration is set according to an application scenario.

[0014] Optionally, the sensor further includes a circuit board protection cover, which is detachably connected to the bottom of the structural housing to fix the circuit board.

[0015] Optionally, the circuit board further includes a plurality of sensor output connecting pins, and the sensor output connecting pins extend from reserved holes on the circuit board protection cover to output the displacement change to the outside.

[0016] The embodiment of the present invention provides a self-resetting linear displacement sensor with a wake-up function, including a structural housing, a magnetic moving shaft assembly, a reset spring, a limit cap, a fixing screw and a circuit board, wherein the reset spring is sleeved on the outside of the structural housing and the magnetic moving shaft assembly, the magnetic moving shaft assembly can be slidably installed inside the structural housing, the limit cap is installed on the magnetic moving shaft assembly through the fixing screw, so that the reset spring receives a pre-tightening force, and the circuit board is installed at the bottom of the structural housing. The magnetic moving shaft assembly includes a magnet, and the circuit board includes a magnetoresistive chip and a micro-control unit. The magnetoresistive chip can be used to output a measurement signal to the micro-control unit according to the relative position with the magnet, and the micro-control unit can calculate the displacement change of the limit cap according to the measurement signal. By using the reset spring, the sensor can realize the function of automatic reset, and at the same time, the magnetoresistive chip is used to integrate the magnet and the magnetoresistive chip into an integral structure, and the micro-control unit is used for calculation, so that the overall installation and measurement are convenient, the volume is small, and it is easy to operate, which can meet the displacement detection needs of small volume structures. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic diagram of the structure of a self-resetting linear displacement sensor with a wake-up function provided in Embodiment 1 of the present invention;

[0018] Figure 2 This is a schematic diagram of assembling a self-resetting linear displacement sensor with a wake-up function provided in Embodiment 1 of the present invention;

[0019] Figure 3 A schematic diagram of the structure of a circuit board provided in Embodiment 1 of the present invention;

[0020] Figure 4 A schematic diagram of the structure of the structural housing provided in the first embodiment of the present invention;

[0021] Figure 5 This is a schematic diagram of the structure of the wake-up function provided in Embodiment 1 of the present invention. DETAILED DESCRIPTION

[0022] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0023] It should be mentioned before discussing the exemplary embodiments in more detail that some exemplary embodiments are described as processes or methods depicted as flow charts. Although the flow charts describe the steps as sequential processes, many of the steps therein can be implemented in parallel, concurrently or simultaneously. In addition, the order of the steps can be rearranged. The process can be terminated when its operation is completed, but can also have additional steps not included in the accompanying drawings. The process can correspond to a method, function, procedure, subroutine, subprogram, etc.

[0024] Embodiment 1

[0025] Figure 1 This is a schematic diagram of the structure of a self-resetting linear displacement sensor with a wake-up function provided in Embodiment 1 of the present invention. Figure 2 This is a schematic diagram of the assembly of a self-resetting linear displacement sensor with a wake-up function provided in Embodiment 1 of the present invention. This embodiment is applicable to the case where a displacement sensor is used for displacement measurement. Figure 1 and Figure 2 As shown, the sensor includes: a structural shell 100, a magnetic movable axis assembly 200, a reset spring 300, a limit cap 400, a fixing screw 500 and a circuit board 600; wherein the reset spring 300 is sleeved on the outside of the structural shell 100 and the magnetic movable axis assembly 200; the magnetic movable axis assembly 200 is slidably installed in the interior of the structural shell 100; the limit cap 400 is installed on the magnetic movable axis assembly 200 through the fixing screw 500, so that the reset spring 300 is subjected to a pre-tightening force; the circuit board 600 is installed at the bottom of the structural shell 100; the magnetic movable axis assembly 200 includes a magnet, and the circuit board 600 includes a magnetoresistive chip and a micro control unit, wherein the magnetoresistive chip is used to output a measurement signal to the micro control unit according to the relative position with the magnet, so that the micro control unit calculates the displacement change of the limit cap according to the measurement signal.

[0026] Specifically, Figure 1 and Figure 2As shown, the top of the structural housing 100 may include a columnar protrusion, and the reset spring 300 may be mounted on the outside of the columnar protrusion so that one end thereof may abut against the structural housing 100. Furthermore, a groove matching the reset spring 300 may be provided at the abutting position on the structural housing 100 to achieve better fixation of the reset spring 300. The magnetic moving shaft assembly 200 may be slidably mounted inside the structural housing 100, specifically, it may slide along the columnar protrusion. Accordingly, the reset spring 300 is also mounted on the outside of the magnetic moving shaft assembly 200. One end of the magnetic moving shaft assembly 200 extending into the interior of the structural housing 100 may be stuck against the interior of the structural housing 100, thereby limiting the magnetic moving shaft assembly 200 from sliding out. The limit cap 400 is installed on the side of the magnetic movable axis assembly 200 away from the structural shell 100 through a fixing screw 500, and can be used to receive external force to generate displacement. On the other hand, the other end of the reset spring 300 can be against the limit cap 400. Then, when the sensor does not have any measured displacement, the relative position of the limit cap 400 and the structural shell 100 can provide a certain pre-tightening force for the reset spring 300.

[0027] like Figure 3 As shown, the circuit board 600 includes a magnetoresistive chip 620 and a microcontroller unit (MCU) 630, and both can be arranged on the substrate 610. The circuit board 600 is installed at the bottom of the structural housing 100, and a magnet is arranged in the magnetic movable shaft assembly 200. In the sliding process of the magnetic movable shaft assembly 200, the relative position between the magnet and the magnetoresistive chip 620 will change, and the magnetic field strength around the magnetoresistive chip 620 will also change, so that the output of the magnetoresistive chip 620 can be changed. Then the implementation principle of the sensor can be: when the sensor does not have any measured displacement, the reset spring 300, due to the preload force, gives a certain support force to the limit cap 400, and the displacement detection amount is in the initial zero position state; when the external pressure applied to the limit cap 400 is greater than the preload force, the magnetic movable shaft assembly 200 begins to change its position, and the output of the magnetoresistive chip 620 has a certain relationship with the above relative position, then the microcontroller unit 630 can be used to calculate the displacement change of the limit cap 400 according to the measurement signal output by the magnetoresistive chip 620. At the same time, since the reset spring 300 is subjected to a pre-tightening force, when the applied external pressure decreases or disappears, the magnetic movable shaft assembly 200 can automatically return or reset, thereby forming a self-resetting displacement sensor.

[0028] On the basis of the above technical solution, optionally, Figure 2 and Figure 4As shown, the magnetic movable axis assembly 200 also includes a sliding positioning structure 210, and the interior of the structural shell 100 includes a sliding structure groove 110. The sliding positioning structure 210 and the sliding structure groove 100 are appropriately slidably matched, so that the magnetic movable axis assembly 200 can be fixed and slid inside the structural shell 100, thereby further simplifying the installation, making the whole more stable and achieving better measurement effects.

[0029] On the basis of the above technical solution, optionally, the microcontroller unit is used to perform nonlinear calibration and temperature compensation on the measurement signal to calculate the displacement change. By performing nonlinear calibration and temperature compensation on the measurement signal output by the magnetoresistive chip by the microcontroller unit, a calibration method for linear measurement of the relative position change between the magnet and the magnetoresistive chip can be obtained, thereby obtaining a linear displacement sensor for the position change of the limit cap 400, which can respond to high-frequency reciprocating measurement requirements.

[0030] On the basis of the above technical solution, optionally, the microcontroller unit is used to control the stop of power supply to the magnetoresistive chip if the sensor is in the zero position state for more than a preset time, so that the sensor enters a dormant state. Specifically, when the sensor is in the initial zero position state, the time for stopping using the sensor can be counted by the timer in the microcontroller unit. Among them, optionally, the preset time is set according to the application scenario, and can be specifically 10-120 seconds. For example, if a time period is set to 30 seconds, when the set period is reached, the microcontroller unit can issue an instruction to cut off the power supply to the magnetoresistive chip and reduce the power consumption of the microcontroller unit, so that the entire sensor is in a dormant state, that is, a power saving mode. When no measurement is performed, the power saving mode can be used to save power, which is more suitable for battery-powered scenarios.

[0031] Further optional, such as Figure 4 and Figure 5 As shown, the structural housing 100 includes two electrical connection pins 120 connected to the circuit board 600, and the electrical connection pins 120 include a short-circuit point 121. The magnetic movable axis assembly 200 also includes a short-circuit wake-up structure. The microcontroller unit is also used for restoring the power supply of the magnetoresistive chip to enable the sensor to enter a working state when the magnetic movable axis assembly 200 is in a dormant state and the two ends of the short-circuit wake-up structure are respectively connected to the two short-circuit points 121 to form a short-circuit switch signal during the movement of the magnetic movable axis assembly 200 under the action of an external force. Figure 3As shown, the circuit board 600 further includes two short-circuit electrical connection points 611, which are respectively used to connect to the two electrical conduction connection pins 120 to transmit the short-circuit switch signal to the micro control unit 630. Specifically, the switch signal of a special mechanical structure design can be used to set a program inside the micro control unit 630 to achieve a self-mechanical structure wake-up function, which can be switched between the sleep state and the working state. The user can also further save energy by adjusting the time of various modes to meet the needs of use in more occasions. Specifically, two electrically conductive connecting pins 120 can be set in the structural shell 100, which can be connected to the circuit board 600 through the short-circuit electrical connection point 611, so that a signal can be transmitted to the micro control unit 630. A short-circuit point 121 for the wake-up function can be set on the electrically conductive connecting pin 120, which can be formed by an inward recess. When the magnetic movable axis assembly 200 is moved a certain distance from the initial position by an external force, the short-circuit wake-up structure thereon can be connected and conducted with the short-circuit point 121, and a short-circuit switch signal can be formed through the two electrically conductive connecting pins 120 and transmitted to the micro control unit 630. After the micro control unit 630 receives the short-circuit switch signal, the sensor can be restored to the working state through internal settings.

[0032] Further optional, such as Figure 5 As shown, the short-circuit wake-up structure includes a short-circuit support spring 221, and two sliding steel balls 222 connected to both ends of the short-circuit support spring 221. The short-circuit point 121 specifically forms the short-circuit switch signal through the sliding steel balls 222. Specifically, the short-circuit support spring 221 can play a supporting role to make it easier for the two sliding steel balls 222 to contact and conduct with the short-circuit point 121, and can also play a buffering role, so as not to affect the sliding of the magnetic moving axis assembly 200. When the magnetic moving axis assembly 200 is moved a certain distance from the initial position by an external force, the sliding steel ball 222 is connected to the short-circuit point 121, and the short-circuit switch signal can be formed through two electrically conductive connecting pins 120, two sliding steel balls 222 and the short-circuit support spring 221 and transmitted to the micro control unit 630.

[0033] On the basis of the above technical solution, optionally, Figure 1 and Figure 2 As shown, the sensor also includes a circuit board protection cover 700, which is detachably connected to the bottom of the structural shell 100 and is used to fix the circuit board 600, so that the circuit board 600 is wrapped between the structural shell 100 and the circuit board protection cover 700 to play a fixing and protective role. At the same time, through the detachable connection method, it is also more convenient to complete the assembly process of the entire sensor from the bottom of the structural shell 100.

[0034] Further optional, such as Figure 3 As shown, the circuit board 600 also includes a plurality of sensor output connection pins 640 ( Figure 3 In the figure, four sensor output connection pins 640 are shown as an example. The sensor output connection pins 640 extend from the reserved holes on the circuit board protection cover 700 to output the displacement change to the outside, so that the calculated displacement change can be better utilized.

[0035] The embodiment of the present invention provides a self-resetting linear displacement sensor with a wake-up function, including a structural housing, a magnetic moving shaft assembly, a reset spring, a limit cap, a fixing screw and a circuit board, wherein the reset spring is sleeved on the outside of the structural housing and the magnetic moving shaft assembly, the magnetic moving shaft assembly can be slidably installed inside the structural housing, the limit cap is installed on the magnetic moving shaft assembly through the fixing screw, so that the reset spring receives a pre-tightening force, and the circuit board is installed at the bottom of the structural housing. The magnetic moving shaft assembly includes a magnet, and the circuit board includes a magnetoresistive chip and a micro-control unit. The magnetoresistive chip can be used to output a measurement signal to the micro-control unit according to the relative position with the magnet, and the micro-control unit can calculate the displacement change of the limit cap according to the measurement signal. By using the reset spring, the sensor can realize the function of automatic reset, and at the same time, the magnetoresistive chip is used to integrate the magnet and the magnetoresistive chip into an integral structure, and the micro-control unit is used for calculation, so that the overall installation and measurement are convenient, the volume is small, and it is easy to operate, which can meet the displacement detection needs of small volume structures.

[0036] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A self-resetting linear displacement sensor with a wake-up function, characterized in that: include: Structural housing, magnetic moving shaft assembly, return spring, limit cap, fixing screw and circuit board; wherein, The reset spring is sleeved on the outside of the structural housing and the magnetic movable shaft assembly; the magnetic movable shaft assembly is slidably mounted inside the structural housing; the limit cap is mounted on the magnetic movable shaft assembly through the fixing screw, so that the reset spring is subjected to a pre-tightening force; the circuit board is mounted on the bottom of the structural housing; The magnetic movable axis assembly includes a magnet, and the circuit board includes a magnetoresistive chip and a microcontroller unit, wherein the magnetoresistive chip is used to output a measurement signal to the microcontroller unit according to a relative position with the magnet, so that the microcontroller unit calculates a displacement change of the limit cap according to the measurement signal; The microcontroller unit is used for controlling to stop supplying power to the magnetoresistive chip if the sensor is in a zero position state for more than a preset time, so that the sensor enters a dormant state; The structural housing includes two electrically conductive connecting pins connected to the circuit board, and the electrically conductive connecting pins include a short-circuit point. The magnetic movable axis assembly also includes a short-circuit wake-up structure. The microcontroller unit is also used for, when the sensor is in a sleep state, if the magnetic movable axis assembly is moved by an external force, so that the two ends of the short-circuit wake-up structure are respectively connected to the two short-circuit points to form a short-circuit switch signal, then the power supply of the magnetoresistive chip is restored to enable the sensor to enter a working state.

2. The self-resetting linear displacement sensor with wake-up function according to claim 1, characterized in that: The magnetic movable shaft assembly also includes a sliding positioning structure, the interior of the structural shell includes a sliding structure groove, and the sliding positioning structure and the sliding structure groove are appropriately slidably matched.

3. The self-resetting linear displacement sensor with wake-up function according to claim 1, characterized in that: The micro control unit is used to perform nonlinear calibration and temperature compensation on the measurement signal to calculate the displacement change.

4. The self-resetting linear displacement sensor with wake-up function according to claim 1, characterized in that: The short circuit wake-up structure includes a short circuit support spring and two sliding steel balls connected to both ends of the short circuit support spring. The short circuit point specifically forms the short circuit switch signal through the sliding steel balls.

5. The self-resetting linear displacement sensor with wake-up function according to claim 1, characterized in that: The circuit board also includes two short-circuit electrical connection points, which are respectively used to connect with the two electrical conduction connection pins to transmit the short-circuit switch signal to the micro control unit.

6. The self-resetting linear displacement sensor with wake-up function according to claim 1, characterized in that: The preset duration is set according to the application scenario.

7. The self-resetting linear displacement sensor with wake-up function according to claim 1, characterized in that: The sensor further comprises a circuit board protection cover, which is detachably connected to the bottom of the structural housing and is used to fix the circuit board.

8. The self-resetting linear displacement sensor with wake-up function according to claim 7, characterized in that: The circuit board also includes a plurality of sensor output connection pins, and the sensor output connection pins extend from reserved holes on the circuit board protection cover to output the displacement change amount to the outside.

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