A non-contact magnetic positioning encoder for a rectification system

Abstract

The present invention belongs to the technical field of automation control applications, and particularly relates to a non-contact magnetic positioning encoder for a deviation rectification system. By setting a reduction gear device and an encoder circuit board, the rotation of the motor shaft drives the reduction gear set to rotate at a reduced speed. Then, the output shaft of the reduction gear set and the electromagnet rotate synchronously. The magnetic chip determines the change in the position of the motor lead screw by sensing the change in the magnetism of the electromagnet. This position change is transmitted to the encoder for recording and storage. By limiting the stroke range of the deviation rectification actuator through the stored encoder position value, the hard contact between the lead screw nut on the deviation rectification actuator and the mechanical limit is avoided, thereby protecting the lead screw, as well as the motor and the motor drive, from being stuck by the mechanical limit and burned out due to stalling. This non-contact magnetic positioning encoder for the deviation rectification system has high limit accuracy, is installed at the rear end of the motor, has a compact structure, occupies a small space, and is very convenient to disassemble and assemble.

Description

Technical Field

[0001] The present invention belongs to the technical field of automation control applications, and particularly relates to a non-contact magnetic positioning encoder for a rectification system. Background Art

[0002] An encoder is a device that compiles signals or data and converts them into signal forms that can be used for communication, transmission, and storage. The encoder converts angular displacement or linear displacement into an electrical signal. The former is called a code disk, and the latter is called a code scale. According to the reading method, encoders can be divided into two types: contact type and non-contact type; according to the working principle, encoders can be divided into incremental type and absolute type: the incremental encoder converts displacement into a periodic electrical signal, and then converts this electrical signal into a counting pulse, and uses the number of pulses to represent the magnitude of the displacement; each position of the absolute encoder corresponds to a definite digital code, so its indication value is only related to the starting and ending positions of the measurement, and has nothing to do with the intermediate process of the measurement.

[0003] In the application of the rectification system, the motors on the rectification actuators generally adopt the structure of a DC brushed motor plus a ball screw, and positioning encoders are not installed on the motors. When the screw runs to both ends, mechanical limit methods are used to prevent the screw nut from running out of the effective range of the screw. Since the screw hits the mechanical limit devices at both ends every time it runs to both ends, it is easy to damage the screw until it is scrapped prematurely. If the motor stalls, phenomena such as motor burnout and driver burnout are also likely to occur, greatly reducing the service life of the motor.

[0004] Another method is to externally install a limit switch or a travel switch on the rectification actuator for limiting. The limit switch or the travel switch is installed outside the rectification actuator. Through the telescopic movement of the screw, the mechanical parts are driven to block the limit switch to cut off the power supply of the motor so that the motor stops, or a start / stop signal is given to the motor to start or stop the motor. Due to the limited sensing range of the limit switch, the positioning accuracy of the motor is greatly limited, and the installation of the limit switch is restricted by the installation site, the installation is relatively troublesome, and it also occupies a certain installation space. Summary of the Invention

[0005] In order to overcome the above technical problems, the present invention provides a non-contact magnetic positioning encoder for a rectification system. By setting a reduction gear device and an encoder circuit board, after the motor shaft is decelerated by the reduction gear set, the magnetic chip determines the change in the stroke position of the ball screw by sensing the change of the electromagnet, and conducts the signal to the encoder circuit board. The encoder limits the stroke range of the rectification actuator, and can effectively protect the ball screw and the motor.

[0006] The technical solution for achieving the above object is:

[0007] The present invention provides a non-contact magnetic positioning encoder for a rectification system, which includes a reduction gear device and a circular encoder circuit board. The reduction gear device is fixedly connected to the encoder circuit board through copper posts with bolts, and there are at least 3 copper posts.

[0008] The reduction gear device includes a circular reduction gear base sleeved outside the motor shaft. There is no contact between the reduction gear base and the motor shaft, and the reduction gear device is fixed to the motor tail end through the reduction gear base.

[0009] The diameter of one end of the reduction gear base connected to the motor is the same as the motor diameter. The end of the reduction gear base far from the motor is provided with a circular step, and the diameter of the circular step is larger than the diameter of the encoder circuit board and smaller than the motor diameter.

[0010] A reduction gear set is embedded at the end of the reduction gear base with the circular step. The reduction gear set is connected to the reduction gear base through bolts, and the diameter of the reduction gear set is smaller than the diameter of the encoder circuit board.

[0011] The reduction gear set is a multi-stage reduction gear set meshing with the motor shaft.

[0012] A transition copper sleeve is sleeved on the output shaft of the reduction gear set, and the copper sleeve is embedded on the output shaft of the reduction gear set. The copper sleeve protrudes from the output shaft of the reduction gear set to form a groove, and an electromagnet with the same size as the groove is embedded in the groove.

[0013] A magnetic chip is provided on the side of the encoder circuit board close to the motor, and semiconductor carriers or conductor carriers are provided inside the magnetic chip.

[0014] A further setting of the present invention is that the reduction gear set meshes with the motor shaft.

[0015] A further setting of the present invention is that there is no relative movement between the electromagnet and the output shaft of the reduction gear set.

[0016] A further setting of the present invention is that the magnetic chip is non-contact, parallel and coaxial with the electromagnet, and the distance between the magnetic chip and the electromagnet is 0.4 mm to 0.6 mm.

[0017] A further setting of the present invention is that only the N pole or the S pole of the electromagnet is close to the magnetic chip.

[0018] A further setting of the present invention is that the magnetic chip is electrically connected to the encoder circuit board.

[0019] In a further setting of the present invention, the AD sampling bit number of the encoder chip in the encoder circuit board is 14 bits, and after being converted into digital quantity, it is output through the SPI port.

[0020] Beneficial effects: The difference between the present invention and the prior art is that the non-contact magnetic positioning encoder of the deviation correction system provided by the present invention, by setting a reduction gear device and an encoder circuit board, the rotation of the motor rotating shaft drives the reduction gear set to rotate at a reduced speed, the output shaft of the reduction gear set drives the electromagnet to rotate synchronously, and the magnetic chip senses the magnetic change of the electromagnet to determine the change of the position. This position change is transmitted to the encoder for recording and storage. By the saved encoder position value, the stroke range of the deviation correction actuator is positioned, avoiding the hard contact between the screw nut on the deviation correction actuator and the mechanical limit, thus protecting the screw rod, and also protecting the motor and the motor drive from being stuck by the mechanical limit and burned out due to blocked rotation. By this way, the movement stroke of the motor ball screw can be restricted to achieve a very high limit accuracy; in addition, the non-contact magnetic positioning encoder of the deviation correction system is installed at the rear end of the motor, with a compact structure, small occupied space, and very convenient disassembly and assembly. Description of the Drawings

[0021] Figure 1 It is a partial cross-sectional schematic view of the non-contact magnetic positioning encoder of the deviation correction system. Detailed Embodiments

[0022] The present invention will be further described below in conjunction with the drawings and specific embodiments.

[0023] Refer to Figure 1 As shown, the present invention provides a non-contact magnetic positioning encoder for a deviation correction system, including a reduction gear device 2 and a circular encoder circuit board 3. The reduction gear device 2 and the encoder circuit board 3 are fixedly connected by three copper columns 4 with bolts (two are shown in the figure), and the three copper columns 4 are evenly distributed on the encoder circuit board 3 at an interval of 120 degrees:

[0024] The reduction gear device 2 includes a circular reduction gear base 21 sleeved outside the motor rotating shaft 5. There is no contact between the reduction gear base 21 and the motor rotating shaft 5. The reduction gear device 2 is fixed at the tail end of the motor 1 through the reduction gear base 21 to support the entire magnetic positioning encoder device;

[0025] The diameter of one end of the reduction gear base 21 connected to the motor 1 is the same as the diameter of the motor 1. A circular step 26 is provided at one end of the reduction gear base 21 away from the motor 1. The diameter of the circular step 26 is larger than the diameter of the encoder circuit board 3 and smaller than the diameter of the motor 1;

[0026] One end of the reduction gear base 21 with a circular step 26 is embedded with a reduction gear set 22. The reduction gear set 22 is connected to the reduction gear base 21 by bolts. The diameter of the reduction gear set 22 is smaller than the diameter of the encoder circuit board 3.

[0027] The reduction gear set 22 is a multi-stage reduction gear set meshed with the motor shaft 5.

[0028] A transition copper sleeve 24 is sleeved on the output shaft 23 of the reduction gear set 22. The copper sleeve 24 is embedded on the output shaft of the reduction gear set 22. The copper sleeve 24 protrudes from the output shaft 23 of the reduction gear set 22 to form a groove, and an electromagnet 6 with the same size as the groove is embedded in the groove.

[0029] On one side of the encoder circuit board 3 close to the motor 1, there is a magnetic chip 7. Inside the magnetic chip 7, there are semiconductor carriers or conductor carriers.

[0030] Preferably but not limited to, the reduction gear set 22 meshes with the motor shaft 5.

[0031] Preferably but not limited to, the electromagnet 6 has no relative movement with the output shaft 23 of the reduction gear set 22, that is, the rotation speed of the electromagnet 6 is the same as the speed of the motor shaft 5 after being reduced by the reduction gear set 22, that is, the same as the speed of the output shaft 23 of the reduction gear.

[0032] Preferably but not limited to, the magnetic chip 7 is non-contact, parallel and coaxial with the electromagnet 6, and the distance between the magnetic chip 7 and the electromagnet 6 is 0.5 mm.

[0033] Preferably but not limited to, only the N pole or S pole of the electromagnet 6 is close to the magnetic chip 7.

[0034] Preferably but not limited to, the magnetic chip 7 is electrically connected to the encoder circuit board 3.

[0035] Preferably but not limited to, the AD sampling bit number of the encoder chip in the encoder circuit board 3 is 14 bits, and after being converted into digital quantity, it is output through the SPI port.

[0036] Specifically, the rotation of the motor 1 drives the reduction gear set 22 to rotate at a reduced speed. The output shaft 23 of the reduction gear set 22 drives the electromagnet 6 to rotate synchronously. The magnetic chip 7 determines the change in the stroke position of the ball screw of the motor 1 by sensing the change of the electromagnet 6, and can record and save the limit position points of the change in the stroke position of the ball screw. Furthermore, the stroke range of the deviation rectification actuator is limited by the data saved by the encoder, avoiding the hard contact between the ball screw nut on the deviation rectification actuator and the mechanical limit, thereby protecting the ball screw, as well as the motor 1 and the motor drive device from being stuck by the mechanical limit and burned out due to stalling. In addition, the non-contact magnetic positioning encoder of this deviation rectification system is installed at the end of the motor 1, with a compact structure, small occupied space, and very convenient disassembly and assembly of the entire magnetic positioning encoder.

[0037] The working principle of the magnetic chip is as follows: Utilizing the magnetoresistance effect, the carriers of the current-carrying conductor or semiconductor carriers inside the magnetic chip 7 are deflected or generate spiral motion due to the Lorentz force of the electromagnet 6, resulting in a change in the potential difference inside the substance (macroscopically manifested as the corresponding change in the electromagnetic resistance value inside the magnetic chip with the change of the external magnetic field). Furthermore, a signal is conducted to the encoder circuit board 3, and the encoder circuit board 3 processes this signal, including recording and saving the signal, and can also be encoded as needed. Conversely, it restricts the rotation of the electromagnet 6 at the end of the output shaft 23, thereby restricting the movement of the motor rotating shaft 5 and the ball screw of the motor 1, enabling the ball screw of the motor 1 to continuously move in a reciprocating motion within the set stroke range, achieving the purpose we need, that is, restricting the stroke range of the ball screw through this non-contact magnetic positioning encoder. Limiting the movement stroke of the motor ball screw in this way can achieve a very high limit accuracy.

[0038] The above specific implementation manners are only preferred embodiments of this creation, and are not intended to limit this creation. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of this creation shall be included within the protection scope of this creation.

Claims

1. A non-contact magnetic positioning encoder for a rectification system, comprising a reduction gear device and a circular encoder circuit board. The reduction gear device and the encoder circuit board are fixedly connected by copper posts with bolts. It is characterized in that: The reduction gear device includes a circular reduction gear base sleeved outside the motor shaft. There is no contact between the reduction gear base and the motor shaft. The reduction gear device is fixed to the end of the motor through the reduction gear base. The diameter of one end of the reduction gear base connected to the motor is the same as the diameter of the motor. A circular step is provided at the end of the reduction gear base away from the motor. The diameter of the circular step is larger than the diameter of the encoder circuit board and smaller than the diameter of the motor. A reduction gear set is embedded at the end of the reduction gear base with the circular step. The reduction gear set is connected to the reduction gear base by bolts. The diameter of the reduction gear set is smaller than the diameter of the encoder circuit board. The reduction gear set is a multi-stage reduction gear set meshed with the motor shaft. A transition copper sleeve is sleeved on the output shaft of the reduction gear set. The copper sleeve is embedded on the output shaft of the reduction gear set. The copper sleeve protrudes from the output shaft of the reduction gear set to form a groove, and an electromagnet with the same size as the groove is embedded in the groove. A magnetic chip is provided on the side of the encoder circuit board close to the motor. Semiconductor carriers or conductor carriers are provided inside the magnetic chip. The magnetic chip is electrically connected to the encoder circuit board. The magnetic chip determines the change in the stroke position of the rectification actuator by sensing the change of the electromagnet, and conducts the signal to the encoder circuit board to limit the stroke range of the rectification actuator by recording and saving the limit position points of the change in the stroke position of the rectification actuator. Among them, the encoder circuit board is encoded as needed to limit the rotation of the electromagnet at the end of the output shaft, and further limit the movement of the motor shaft and the motor ball screw, so that the ball screw of the motor makes a reciprocating movement within the stroke range between the set limit position points.

2. A non-contact magnetic positioning encoder for a rectification system as described in claim 1, It is characterized in that: The reduction gear set is meshed with the motor shaft.

3. A non-contact magnetic positioning encoder for a rectification system as described in claim 1, It is characterized in that: There is no relative movement between the electromagnet and the output shaft of the reduction gear set.

4. A non-contact magnetic positioning encoder for a rectification system as described in claim 1, It is characterized in that: The magnetic chip is non-contact, parallel and coaxial with the electromagnet, and the distance between the magnetic chip and the electromagnet is 0.4 mm to 0.6 mm.

5. A non-contact magnetic positioning encoder for a rectification system as described in claim 1, It is characterized in that: Only the N pole or the S pole of the electromagnet is close to the magnetic chip.

6. A non-contact magnetic positioning encoder for a rectification system as described in claim 1, It is characterized in that: The AD sampling bit number of the encoder chip in the encoder circuit board is 14 bits, and after being converted into digital quantity, it is output through the SPI port.

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