Method for realizing long-distance signal transmission of absolute value encoder

Abstract

The invention discloses a method for realizing long-distance signal transmission of an absolute value encoder, which comprises the following steps of: 1) installing an SSI + decoder of the absolute type encoder on site, and reading and setting an initial position value of the encoder through upper computer software; 2) connecting to an X5 end of a decoder through a USB (Universal Serial Bus) to 485 line; (3) upper computer software in the computer is opened, a serial port is opened, the current position of the encoder is obtained, and real-time position data of the encoder can be read; (4) after programming is finished, the set initial position value, the single-circle resolution ratio and the number of circles of multiple circles are all stored in the encoder chip until data are changed next time; and (5) an X5 port can be externally connected with an RS485 display instrument and is used for displaying the position data of the current encoder in real time. By means of the absolute encoder SSI and the decoder, the farthest transmission distance can reach 350 m, data are stable and reliable, and linearity is good.

Description

Technical Field

[0001] The invention relates to the field of encoder signal transmission, and in particular to a method for realizing long-distance transmission of absolute encoder signals. Background Art

[0002] In existing encoders, the clock frequency of encoder communication of SSI communication protocol is between 100kHz and 1MkHz. The transmission distance is inversely proportional to the clock frequency. When the clock frequency is 1MHz, the transmission distance is only about 50m. When the clock frequency is 10KHz, the safe transmission distance is about 200m. In addition, the data delay is serious.

[0003] The installation location of the tilt and probe encoder on the top of the blast furnace is about 300m away from the central control room. The real-time data feedback from the encoder to the central control DCS module cannot be guaranteed, and the material level regulating valve actuator with closed-loop control cannot achieve real-time control. This fluctuation will cause catastrophic failures in the stability of fuel supply. Ensuring the stability of the sensor feedback signal is an important part of production quality assurance.

[0004] Therefore, it is necessary to develop new methods for long-distance transmission of encoder signals to improve data stability. Summary of the invention

[0005] Purpose of the invention: In view of the shortcomings and defects of the prior art, the present invention provides a method for realizing long-distance transmission of absolute encoder signals. Through the absolute encoder SSI + decoder method, the transmission distance can reach up to 350m, the data is stable and reliable, and the linearity is relatively good.

[0006] Technical solution: A method for realizing long-distance transmission of absolute encoder signals of the present invention is characterized by comprising the following steps:

[0007] 1) Install the absolute encoder SSI + decoder on site, and read and set the encoder's starting position value through the host computer software;

[0008] 2) Connect to the decoder X5 terminal through a USB to 485 cable;

[0009] 3) Open the host computer software in the computer, open the serial port, obtain the current position of the encoder, and then read the real-time position data of the encoder;

[0010] 4) After programming, the set starting position value, single-turn resolution, and multi-turn number of turns will be stored in the encoder chip until the next data change;

[0011] 5) The X5 port can be connected to an RS485 display instrument to display the current encoder position data in real time.

[0012] The decoder is provided with X1, X2, X3, X4 and X5 ports.

[0013] Wherein, the decoder is respectively connected with the absolute encoder SSI, the power module, the PLC control module and the display instrument.

[0014] Wherein, the absolute encoder SSI comprises a Hall magnetic chip, a magnet, an optical code disk and an encoder shaft which are connected in sequence.

[0015] Wherein, the optical code disc is provided with an optical scanner and an infrared light emitting tube.

[0016] Wherein, the absolute encoder SSI includes a single-turn part and a multi-turn part.

[0017] Among them, the single-turn part of the absolute encoder SSI: through the principle of infrared optical scanning, the light-transmitting slits pre-engraved on the glass grating form a binary or Gray code data channel at 360 degrees, which is optically scanned to form position information one by one, and is converted into electrical signal output. The MCU calculates the position signal output and converts it into various standard communication protocol circuit outputs.

[0018] Among them, the multi-turn part of the absolute encoder SSI: the encoder's main shaft meshes with the gear of the same modulus, the gears are arranged according to different speed ratios, the gears are equipped with permanent magnets, and the corresponding position of the circuit board is affixed with a Hall magnetic chip. By rotating the encoder main shaft, the position beyond 360 degrees will be rotated by the gear meshing with it, and the position data will be captured by the Hall chip.

[0019] The decoder converts the absolute encoder SSI through FPGA into a parameterizable form through PC software. The decoder programs the encoder, sets the zero point, the resolution, and adjusts the counting direction.

[0020] Wherein, the absolute encoder SSI adopts synchronous serial communication, and FPGA transcodes to adopt Parallel parallel communication.

[0021] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: the present invention can make the transmission distance reach up to 350m through the absolute encoder SSI + decoder, the data is stable and reliable, and the linearity is relatively good. The present invention improves the structure and protection level of the product and adopts the C / S debugging method to achieve a faster installation and debugging method. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of the present invention;

[0023] Figure 2 It is a structural schematic diagram of a decoder of the present invention;

[0024] Figure 3 It is a structural schematic diagram of the absolute encoder of the present invention;

[0025] Figure 4 is a structural block diagram of a decoder of the present invention;

[0026] In the figure, 1 is a Hall magnetic chip; 2 is a magnet; 3 is an optical scanner; 4 is an optical code disk; 5 is an encoder shaft; and 6 is an infrared light-emitting tube. DETAILED DESCRIPTION

[0027] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and specific implementation methods.

[0028] The method for realizing long-distance transmission of absolute encoder signals of the present invention comprises the following steps:

[0029] 1) Install the absolute encoder SSI + decoder on site, and read and set the encoder's starting position value through the host computer software;

[0030] 2) Connect to the decoder X5 terminal through a USB to 485 cable;

[0031] 3) Open the host computer software in the computer, open the serial port, obtain the current position of the encoder, and then read the real-time position data of the encoder;

[0032] 4) After programming, the set starting position value, single-turn resolution, and multi-turn number of turns will be stored in the encoder chip until the next data change;

[0033] 5) The X5 port can be connected to an RS485 display instrument to display the current encoder position data in real time.

[0034] The decoder of the present invention is provided with X1, X2, X3, X4 and X5 ports. The decoder is respectively connected with the absolute encoder SSI, the power module, the PLC control module and the display instrument. The decoder converts the absolute encoder SSI into parameters that can be parameterized through PC software through FPGA, and the decoder programs the encoder, sets the zero point, the resolution and adjusts the counting direction.

[0035] The absolute encoder SSI of the present invention comprises a Hall magnetic chip 1, a magnet 2, an optical code disk 4 and an encoder shaft 5 connected in sequence. An optical scanner 3 and an infrared light-emitting tube 6 are arranged on the optical code disk 4. The absolute encoder SSI comprises a single-turn part and a multi-turn part. The single-turn part of the absolute encoder SSI: through the principle of infrared optical scanning, the light-transmitting slits pre-engraved on the glass grating form a binary or Gray code data channel at 360 degrees, so that they are optically scanned to form position information one by one, which are converted into electrical signal outputs one by one, and the position signals output by the MCU are calculated in and out, and converted into various standard communication protocol circuit outputs. The multi-turn part of the absolute encoder SSI: the gears with the same modulus are meshed with the encoder's main shaft, and the gears are arranged according to different speed ratios. The gears are equipped with permanent magnets, and the corresponding position circuit board is affixed with a Hall magnetic chip. By rotating the encoder main shaft, the position beyond 360 degrees will be rotated by the gears meshed with it, and the Hall chip will capture the position data. The absolute encoder SSI uses synchronous serial communication, and FPGA transcoding uses parallel communication.

[0036] The present invention can make the transmission distance reach up to 350m through the absolute encoder SSI+decoder mode, the data is stable and reliable, and the linearity is relatively good. The present invention improves the structure and protection level of the product and adopts the C / S debugging mode to achieve a faster installation and debugging mode.

Claims

1. A method for realizing long-distance transmission of absolute encoder signals, characterized in that: The steps include: 1) Install the absolute encoder SSI + decoder on site, and read and set the encoder's starting position value through the host computer software; 2) Connect to the decoder X5 terminal through a USB to 485 cable; 3) Open the host computer software in the computer, open the serial port, obtain the current position of the encoder, and then read the real-time position data of the encoder; 4) After programming, the set starting position value, single-turn resolution, and multi-turn number of turns will be stored in the encoder chip until the next data change; 5) The X5 port can be connected to an RS485 display instrument to display the current encoder position data in real time.

2. The method for realizing long-distance transmission of absolute encoder signals according to claim 1, characterized in that: The decoder is provided with X1, X2, X3, X4 and X5 ports.

3. The method for realizing long-distance transmission of absolute encoder signals according to claim 1, characterized in that: The decoder is respectively connected with the absolute encoder SSI, the power module, the PLC control module and the display instrument.

4. The method for realizing long-distance transmission of absolute encoder signals according to claim 1, characterized in that: The absolute encoder SSI comprises a Hall magnetic chip (1), a magnet (2), an optical code disk (4) and an encoder shaft (5) which are connected in sequence.

5. The method for realizing long-distance transmission of absolute encoder signals according to claim 4, characterized in that: The optical code disk (4) is provided with an optical scanner (3) and an infrared light-emitting tube (6).

6. The method for realizing long-distance transmission of absolute encoder signals according to claim 1, characterized in that: The absolute encoder SSI comprises a single-turn part and a multi-turn part.

7. The method for realizing long-distance transmission of absolute encoder signals according to claim 6, characterized in that: The single-turn part of the absolute encoder SSI: through the principle of infrared optical scanning, the light-transmitting slits pre-engraved on the glass grating form a binary or Gray code data channel at 360 degrees, which is optically scanned to form position information, which is converted into electrical signal output. The MCU calculates the position signal output and converts it into various standard communication protocol circuit outputs.

8. The method for realizing long-distance transmission of absolute encoder signals according to claim 6, characterized in that: The multi-turn part of the absolute encoder SSI described above: the encoder's main shaft meshes with a gear of the same modulus, the gears are arranged according to different speed ratios, the gears are equipped with permanent magnets, and a Hall magnetic chip is attached to the circuit board at the corresponding position. By rotating the encoder main shaft, the position beyond 360 degrees will be rotated by the meshed gear, and the Hall chip will capture the position data.

9. The method for realizing long-distance transmission of absolute encoder signals according to claim 1, characterized in that: The decoder converts the absolute encoder SSI through FPGA into a code that can be parameterized through PC software. The decoder programs the encoder, sets the zero point, the resolution, and adjusts the counting direction.

10. The method for realizing long-distance transmission of absolute encoder signals according to claim 9, characterized in that: The absolute encoder SSI adopts synchronous serial communication, and FPGA transcodes to adopt Parallel parallel communication.

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