An eddy current sensor with automatic calibration function

Abstract

The invention discloses an eddy current sensor with an automatic calibration function, which relates to the technical field of eddy current sensors and comprises a motor and a shell, wherein the shell is arranged on a driving shaft of the motor, an excitation coil, a receiving coil and an ASIC circuit are arranged in the shell, a calibration device is arranged outside the motor, and the calibration device comprises: a fan and a rotating body, and when a displacement plate moves, the excitation coil, the receiving coil and the ASIC circuit in the shell cooperate with each other, so that the amplitude and polarity of an output voltage signal change with the position of the displacement plate, and then the position information of the displacement plate can be obtained, thereby realizing the static calibration of the eddy current sensor, and a toggle rod impacts against a sawtooth to generate vibration through the impact, so that the excitation coil, the receiving coil and the ASIC circuit in the shell cooperate with each other, so as to realize the function of dynamic calibration of the eddy current sensor.

Description

Technical Field

[0001] The invention relates to the technical field of eddy current sensors, in particular to an eddy current sensor with an automatic calibration function. Background Art

[0002] The important role of sensor technology in social development With the rapid development of science and technology, the testing and control technology of non-physical quantities has been more and more widely used in aerospace, aviation, transportation, metallurgy, machinery manufacturing, petrochemical, light industry, technical supervision and testing and other technical fields, and is also gradually introduced into people's daily life; the eddy current sensor adopts the principle of induced eddy current. When the coil with high-frequency current is close to the metal to be measured, the high-frequency electromagnetic field generated by the high-frequency current on the coil will generate an induced current on the metal surface, which is called eddy current in electromagnetics; the eddy current effect is related to the distance between the metals to be measured and the parameters such as conductivity, magnetic permeability, geometric shape and size of the coil, and current frequency; the distance change between the metal to be measured and the sensor probe can be converted into voltage or current change through the circuit; the eddy current sensor is based on this principle to measure the displacement, vibration and other parameters of the metal object; the eddy current sensor can measure the relative displacement between the metal conductor to be measured and the surface of the sensor probe in a non-contact manner, and is a non-contact linear measurement tool;

[0003] Existing eddy current sensors usually perform measurements directly without a self-calibration function. If calibration is required, the eddy current sensor needs to be disassembled to prevent calibration on dedicated testing equipment, which is a time-consuming and labor-intensive process. Summary of the invention

[0004] The object of the present invention is to provide an eddy current sensor with an automatic calibration function to solve the problems raised in the prior art.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] An eddy current sensor with an automatic calibration function comprises a motor and a shell, wherein the shell is arranged on the driving shaft of the motor, an excitation coil, a receiving coil and an ASIC circuit are arranged inside the shell, and a calibration device is arranged outside the motor, wherein the calibration device comprises: a fan and a rotating body.

[0007] Preferably, the fan is arranged outside the motor, a micro motor is arranged on one side of the motor, a driving shaft of the micro motor is connected to the fan, and a magnet is arranged at the end of the blade of the fan.

[0008] Preferably, the rotating body includes: a drive ring, which is arranged on a side of the motor away from the shell, the drive ring is rotatably connected to the outside of the motor, a magnetic block is arranged inside the drive ring, and the magnetic poles of the magnet on the side opposite to the magnetic block are opposite.

[0009] Preferably, a toggle ring is provided on the side of the driving ring close to the shell, and the toggle ring is composed of a plurality of toggle rods and a rotating ring, a plurality of springs are provided between the rotating ring and the driving ring, a plurality of the toggle rods are provided on the side of the rotating ring away from the driving ring, and a plurality of the toggle rods are arranged around the axis of the rotating ring.

[0010] Preferably, a serrated ring is provided on the side of the toggle ring away from the driving ring, the serrated ring is rotatably connected to the motor, a plurality of saw teeth are provided on the side of the serrated ring close to the toggle rod, the plurality of saw teeth are arranged around the axis of the serrated ring, and a plurality of round rods are provided on the side of the serrated ring away from the saw teeth, the plurality of round rods are arranged around the axis of the serrated ring.

[0011] Preferably, a fixing ring is provided on one side of the sawtooth ring close to the shell, and a displacement plate is provided between the fixing ring and the shell.

[0012] Preferably, a plurality of power chambers are provided on the fixed ring, a worm gear is provided in the power chamber, the worm gear is meshed with a round rod, the worm gear is rotationally connected to the power chamber, a crankshaft is connected to the worm gear, a piston rod is provided on the crankshaft, the other end of the piston rod passes through the fixed ring and is connected to a displacement plate, and the displacement plate is slidably connected to the motor.

[0013] Preferably, there is a gap between two adjacent toggle rods.

[0014] When the eddy current sensor needs to be calibrated, the controller first controls the micro motor in the motor to start, and the drive shaft of the micro motor drives the fan to rotate. During the rotation of the fan, several magnets are driven to rotate. Since a magnetic block is arranged inside the driving ring, and the magnetic poles of the magnet opposite to the magnetic block are opposite, when the magnet rotates, the magnetic force of the magnet attracts the magnetic block, and then the magnetic block generates a rotational force under the action of the magnet, and then the magnetic block drives the driving ring to rotate;

[0015] When the eddy current sensor needs to be statically calibrated, the controller controls the driving shaft of the micro motor to rotate clockwise, and then the driving ring also rotates clockwise. When the driving ring rotates, it drives the rotating ring to rotate clockwise, and when the rotating ring rotates, it drives several toggle rods to rotate. When the toggle rod rotates clockwise, it encounters the sawtooth, so that the sawtooth blocks the toggle rod, and then when the toggle rod rotates, it drives the sawtooth ring to rotate, and when the sawtooth ring rotates, it drives the round rod to rotate around the axis of the sawtooth ring. Since the round rod is meshed with the worm gear, the round rod drives the worm gear to rotate, and when the worm gear rotates, it drives the crankshaft to rotate, and when the crankshaft rotates, it drives the piston rod to move, and the piston rod drives the displacement plate to move along the axis of the motor. During the movement of the displacement plate, the excitation coil, the receiving coil and the ASIC circuit in the shell cooperate with each other, so that the amplitude and polarity of the output voltage signal change with the position of the displacement plate, and then the position information of the displacement plate can be obtained, thereby realizing the static calibration of the eddy current sensor;

[0016] When it is necessary to perform dynamic calibration on the eddy-current sensor, first control the micro motor to rotate clockwise to move the displacement plate, and then read the DC voltage output by the eddy-current sensor to make the installation voltage reach the specified value, and then control the micro motor to rotate counterclockwise through the controller, and then the fan drives the magnet to rotate counterclockwise, so that the drive ring also rotates counterclockwise under the action of the magnetic block, and the driving ring drives the toggle ring to rotate during the rotation of the driving ring. During the rotation of the toggle ring, the toggle rod contacts the surface of the sawtooth. Since the toggle rod rotates counterclockwise, the toggle rod will not be blocked by the sawtooth when rotating. When the toggle rod moves along the inclined surface of the sawtooth, the toggle rod is continuously squeezed by the sawtooth, and then the toggle ring moves to the side close to the driving ring, and then the rotating ring squeezes and rotates. The spring between the rotating ring and the driving ring, when the toggle rod moves to the top of the sawtooth slope, the toggle rod loses the squeezing force of the sawtooth slope, and then the toggle ring moves under the elastic force of the spring, and the toggle rod hits the sawtooth, and vibration is generated by the impact, so that the exciting coil, the receiving coil and the ASIC circuit in the shell cooperate with each other to realize the function of dynamic calibration of the eddy current sensor; because the shell, the displacement plate, and the toggle ring and the sawtooth ring that generate vibration are all arranged on the same axis, and then the shell, the displacement plate, and the toggle ring and the sawtooth ring that generate vibration are in a concentric state, thereby avoiding the need to first adjust the shell and the displacement plate, and the toggle ring and the sawtooth ring that generate vibration to a concentric state before calibration, thereby improving the efficiency of dynamic calibration and saving calibration time;

[0017] By utilizing the fan to rotate in two directions, clockwise or counterclockwise, the displacement of the displacement plate and the collision of the toggle rod with the sawtooth are respectively realized, thereby realizing the static automatic calibration and dynamic automatic calibration of the eddy current sensor respectively. There is no need to disassemble the eddy current sensor and then install it in a special calibration device for calibration, thereby saving the time for disassembly and installation and further improving the efficiency of the calibration.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. The fan is rotated in two directions, clockwise or counterclockwise, to achieve the displacement of the displacement plate and the collision of the toggle rod with the sawtooth, thereby achieving the static automatic calibration and dynamic automatic calibration of the eddy current sensor. There is no need to disassemble the eddy current sensor and then install it in a special calibration device for calibration, which saves the time of disassembly and installation and further improves the efficiency of calibration.

[0020] 2. When the sawtooth ring rotates, it drives the round rod to rotate around the axis of the sawtooth ring. Since the round rod is meshed with the worm gear, the round rod drives the worm gear to rotate. When the worm gear rotates, it drives the crankshaft to rotate. When the crankshaft rotates, it drives the piston rod to move. The piston rod drives the displacement plate to move along the axis of the motor. During the movement of the displacement plate, the excitation coil, receiving coil and ASIC circuit in the shell cooperate with each other, so that the amplitude and polarity of the output voltage signal change with the position of the displacement plate, and then the position information of the displacement plate can be obtained, thereby realizing the static calibration of the eddy current sensor.

[0021] 3. When the toggle rod moves to the top of the sawtooth slope, the toggle rod loses the squeezing force of the sawtooth slope, and then the toggle ring moves under the action of the elastic force of the spring, and the toggle rod hits the sawtooth, generating vibration through the impact, so that the excitation coil, the receiving coil and the ASIC circuit in the shell cooperate with each other to realize the function of dynamic calibration of the eddy current sensor; because the shell, the displacement plate, and the toggle ring and the sawtooth ring that generate vibration are all arranged on the same axis, and then the shell, the displacement plate, and the toggle ring and the sawtooth ring that generate vibration are in a concentric state, thereby avoiding the need to first adjust the shell and the displacement plate, and the toggle ring and the sawtooth ring that generate vibration to a concentric state before calibration, thereby improving the efficiency of dynamic calibration and saving calibration time. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A perspective view of the present invention;

[0023] Figure 2 is a schematic diagram of the structure of the displacement device;

[0024] Figure 3 It is a schematic diagram of the internal structure of the present invention;

[0025] Figure 4 It is an internal front view of the present invention;

[0026] Figure 5 It is a schematic diagram of the structure of the fixed ring and the displacement plate;

[0027] Figure 6 It is a structural schematic diagram of the toggle ring;

[0028] Figure 7 It is a structural schematic diagram of a sawtooth ring;

[0029] In the figure: 1. motor; 11. housing;

[0030] 2. Verification device; 21. Fan; 22. Rotating body; 23. Driving ring; 24. Toggle ring; 241. Toggle rod; 242. Rotating ring; 25. Sawtooth ring; 251. Sawtooth; 252. Round rod; 26. Fixed ring; 261. Power chamber; 262. Worm gear; 263. Crankshaft; 264. Piston rod; 27. Displacement plate. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] Example: Figure 1-Figure 7 As shown, the present invention provides a technical solution of an eddy current sensor with an automatic calibration function, including a motor 1 and a shell 11, wherein the shell 11 is arranged on the driving shaft of the motor 1, an excitation coil, a receiving coil and an ASIC circuit are arranged in the shell 11, and a calibration device 2 is arranged outside the motor 1, and the calibration device 2 includes: a fan 21 and a rotating body 22.

[0033] As a specific embodiment of the present invention, the fan 21 is arranged outside the motor 1, a micro motor is arranged on one side of the motor 1, a driving shaft of the micro motor is connected to the fan 21, and a magnet is arranged at the end of the blade of the fan 21.

[0034] As a specific embodiment of the present invention, the rotating body 22 includes: a drive ring 23, the drive ring 23 is arranged on the side of the motor 1 away from the housing 11, the drive ring 23 is rotatably connected to the outside of the motor 1, and a magnetic block is arranged inside the drive ring 23, and the magnetic poles of the magnet on the side opposite to the magnetic block are opposite.

[0035] As a specific embodiment of the present invention, a toggle ring 24 is provided on the side of the driving ring 23 close to the shell 11, and the toggle ring 24 is composed of a plurality of toggle rods 241 and a rotating ring 242. A plurality of springs are provided between the rotating ring 242 and the driving ring 23, and a plurality of the toggle rods 241 are provided on the side of the rotating ring 242 away from the driving ring 23. The plurality of the toggle rods 241 are arranged around the axis of the rotating ring 242.

[0036] As a specific embodiment of the present invention, a sawtooth ring 25 is provided on the side of the toggle ring 24 away from the driving ring 23, and the sawtooth ring 25 is rotatably connected to the motor 1. A plurality of saw teeth 251 are provided on the side of the sawtooth ring 25 close to the toggle rod 241, and the plurality of saw teeth 251 are arranged around the axis of the sawtooth ring 25. A plurality of round rods 252 are provided on the side of the sawtooth ring 25 away from the saw teeth 251, and the plurality of round rods 252 are arranged around the axis of the sawtooth ring 25.

[0037] As a specific implementation of the present invention, a fixing ring 26 is disposed on a side of the sawtooth ring 25 close to the housing 11 , and a displacement plate 27 is disposed between the fixing ring 26 and the housing 11 .

[0038] As a specific embodiment of the present invention, a plurality of power chambers 261 are provided on the fixing ring 26, a worm gear 262 is provided in the power chamber 261, the worm gear 262 is meshed with the round rod 252, the worm gear 262 is rotationally connected to the power chamber 261, a crankshaft 263 is connected to the worm gear 262, a piston rod 264 is provided on the crankshaft 263, the other end of the piston rod 264 passes through the fixing ring 26 and is connected to the displacement plate 27, and the displacement plate 27 is slidably connected to the motor 1.

[0039] As a specific implementation of the present invention, there is a gap between two adjacent toggle rods 241 .

[0040] Working principle of the present invention:

[0041] When the eddy current sensor needs to be calibrated, the controller first controls the micro motor in the motor 1 to start, and the driving shaft of the micro motor drives the fan 21 to rotate. During the rotation of the fan 21, several magnets are driven to rotate. Since a magnetic block is arranged inside the driving ring 23, and the magnetic poles of the magnet opposite to the magnetic block are opposite, when the magnet rotates, the magnetic force of the magnet attracts the magnetic block, and then the magnetic block generates a rotational force under the action of the magnet, and then the magnetic block drives the driving ring 23 to rotate;

[0042] When the eddy current sensor needs to be statically calibrated, the controller controls the drive shaft of the micro motor to rotate clockwise, and then the drive ring 23 also rotates clockwise. When the drive ring 23 rotates, it drives the rotating ring 242 to rotate clockwise. When the rotating ring 242 rotates, it drives several toggle rods 241 to rotate. When the toggle rod 241 rotates clockwise, it encounters the sawtooth 251, so that the sawtooth 251 blocks the toggle rod 241. Then, when the toggle rod 241 rotates, it drives the sawtooth ring 25 to rotate. When the sawtooth ring 25 rotates, it drives the round rod 252 to rotate around the axis of the sawtooth ring 25. 52 meshes with the worm gear 262, and then the round rod 252 drives the worm gear 262 to rotate, and when the worm gear 262 rotates, it drives the crankshaft 263 to rotate, and when the crankshaft 263 rotates, it drives the piston rod 264 to move, and the piston rod 264 drives the displacement plate 27 to move along the axis of the motor 1. During the movement of the displacement plate 27, the excitation coil, the receiving coil and the ASIC circuit in the housing 11 cooperate with each other, so that the amplitude and polarity of the output voltage signal change with the position of the displacement plate 27, and then the position information of the displacement plate 27 can be obtained, thereby realizing the static calibration of the eddy current sensor;

[0043] When it is necessary to perform dynamic calibration on the eddy current sensor, the micro motor is first controlled to rotate clockwise so that the displacement plate 27 moves, and then the DC voltage output by the eddy current sensor is read, so that the installation voltage reaches the specified value, and then the micro motor is controlled by the controller to rotate in the counterclockwise direction, and then the fan 21 drives the magnet to rotate counterclockwise, so that the drive ring 23 also rotates counterclockwise under the action of the magnetic block, and the driving ring 23 drives the toggle ring 24 to rotate during the rotation of the driving ring 23. During the rotation of the toggle ring 24, the toggle rod 241 contacts the surface of the sawtooth 251. Since the toggle rod 241 rotates counterclockwise, the toggle rod 241 will not be blocked by the sawtooth 251 when rotating. When the toggle rod 241 moves along the inclined surface of the sawtooth 251, the toggle rod 241 is continuously squeezed by the sawtooth 251, and then the toggle ring 24 moves to the side close to the driving ring 23, and then the rotating ring 242 squeezes the rotating ring The spring between the toggle rod 242 and the drive ring 23, when the toggle rod 241 moves to the top of the inclined surface of the sawtooth 251, the toggle rod 241 loses the squeezing force of the inclined surface of the sawtooth 251, and then the toggle ring 24 moves under the action of the elastic force of the spring, and the toggle rod 241 hits the sawtooth 251, and vibration is generated by the impact, so that the excitation coil, the receiving coil and the ASIC circuit in the shell 11 cooperate with each other to realize the function of dynamic calibration of the eddy current sensor; because the shell 11, the displacement plate 27, and the toggle ring 24 and the sawtooth ring 25 that generate vibration are all arranged on the same axis, and then the shell 11, the displacement plate 27, and the toggle ring 24 and the sawtooth ring 25 that generate vibration are in a concentric state, thereby avoiding the need to first adjust the shell 11 and the displacement plate 27, and the toggle ring 24 and the sawtooth ring 25 that generate vibration to a concentric state before calibration, thereby improving the efficiency of dynamic calibration and saving calibration time.

[0044] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. An eddy current sensor with automatic calibration function, characterized in that: The invention comprises a motor (1) and a housing (11), wherein the housing (11) is arranged on a driving shaft of the motor (1), an excitation coil, a receiving coil and an ASIC circuit are arranged inside the housing (11), and a verification device (2) is arranged outside the motor (1), wherein the verification device (2) comprises: a fan (21) and a rotating body (22); The rotating body (22) comprises: a driving ring (23); a toggle ring (24) is arranged on a side of the driving ring (23) close to the housing (11); the toggle ring (24) is composed of a plurality of toggle rods (241) and a rotating ring (242); a sawtooth ring (25) is arranged on a side of the toggle ring (24) away from the driving ring (23); the sawtooth ring (25) is rotatably connected to the motor (1); a plurality of saw teeth (251) are arranged on a side of the sawtooth ring (25) close to the toggle rod (241); A plurality of round rods (252) are arranged on a side away from the sawtooth (251), a fixed ring (26) is arranged on a side of the sawtooth ring (25) close to the housing (11), a displacement plate (27) is arranged between the fixed ring (26) and the housing (11), a plurality of power chambers (261) are arranged on the fixed ring (26), a worm gear (262) is arranged in the power chamber (261), a crankshaft (263) is connected to the worm gear (262), and a piston rod (264) is arranged on the crankshaft (263); The fan (21) is arranged outside the motor (1), a micro motor is arranged on one side of the motor (1), a driving shaft of the micro motor is connected to the fan (21), and a magnet is arranged at the end of a blade of the fan (21); The drive ring (23) is arranged on a side of the motor (1) away from the housing (11), the drive ring (23) is rotatably connected to the outside of the motor (1), a magnetic block is arranged inside the drive ring (23), and the magnetic poles of the side of the magnet opposite to the magnetic block are opposite; A plurality of springs are arranged between the rotating ring (242) and the driving ring (23); a plurality of the toggle rods (241) are arranged on a side of the rotating ring (242) away from the driving ring (23); and the plurality of the toggle rods (241) are arranged around the axis of the rotating ring (242).

2. The eddy current sensor with automatic calibration function according to claim 1, characterized in that: A plurality of the saw teeth (251) are arranged around the axis of the saw tooth ring (25), and a plurality of the round rods (252) are arranged around the axis of the saw tooth ring (25).

3. The eddy current sensor with automatic calibration function according to claim 1, characterized in that: The worm gear (262) is meshed with the round rod (252), the worm gear (262) is rotationally connected to the power chamber (261), the other end of the piston rod (264) passes through the fixing ring (26) and is connected to the displacement plate (27), and the displacement plate (27) is slidably connected to the motor (1).

4. The eddy current sensor with automatic calibration function according to claim 3, characterized in that: There is a gap between two adjacent toggle rods (241).

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