Incremental magnetic induction bus type encoder for high-speed high-precision machine tool main shaft and electric main shaft

Abstract

The invention relates to an incremental magnetic induction bus type encoder for a high-speed high-precision machine tool main shaft and electric main shaft. The incremental magnetic induction bus type encoder comprises a measurement gear and a magnetic induction read head; a magnetic induction component, a signal conditioning circuit, a reference zero point comparator circuit and a FPGA (Field Programmable Gate Array) interpolation sub-division circuit are arranged in the magnetic induction read head; the magnetic induction component is installed to be tangent to the circumference of the measurement gear; the magnetic induction component performs non-contact scanning on the measurement gear to produce a sine and cosine orthogonal differential signal and a reference zero-point differential signal, after the sine and cosine orthogonal differential signal and the reference zero-point differential signal are conditioned through the signal conditioning circuit, the DC biased error, the amplitude error and the orthogonal-phase error of the sine and cosine orthogonal differential signal and the reference zero-point differential signal are corrected and compensated in real time by the FPGA interpolation subdivision circuit, thereby respectively generating a relative position value of a rotating angle of a rotating shaft with respect to the power-on moment and an absolute position value of the rotating angle of the rotating shaft with respect to the reference zero-point signal in combination with the reference zero-point comparator circuit; the mechanical transmission structure is simple, the machine tool main shaft positioning and the repeated positioning precision are improved, and the overall measurement precision and processing efficiency of a numerically-controlled machine tool are improved.

Description

technical field [0001] The present invention relates to an encoder (Encoder), in particular to a high-speed high-precision machine tool spindle, electric spindle magnetic induction incremental bus encoder, which can be widely used in the fields of numerical control machine tools, robots, elevators and industrial automation. Background technique [0002] An encoder is a sensor used to detect angle, position, speed and acceleration. It is a device that compiles and converts the angular displacement or linear displacement of mechanical rotation into an electrical signal that can be used for communication, transmission and storage. Precision measuring devices that combine machinery and electronics are widely used in many fields such as motors, automobiles, wind power, and robots. In terms of measurement function, encoders can be divided into incremental encoders (also called incremental encoders) and absolute encoders. From the measurement principle, encoders include photoelect...

AI Technical Summary

Problems solved by technology

[0014] In order to solve the technical problem of low encoder control accuracy and reliability in the prior art, the present invention provides a magnetic induction incremental bus encoder suitable for high-speed high-precision machine tool spindles and electric spindles. The encoder uses gear induction magnetic force lines The working principle is to perform non-contact scanning on the measuring gear to generate high-reliability sine-cosine quadrature differential signals and reference zero point differential signals. FPGA field programmable logic devices are used to realize high-precision interpolation and subdivision of sine-cosine signals. Combined with the reference zero point comparator circuit, the relative position value of the high line number relative to the rotation angle of the rotating shaft at the power-on moment and the absolute position value of the high line number relative to the rotating shaft rotation angle of the reference zero point signal are respectively generated inside the encoder. While reducing the complex mechanical transmission mechanism, the positioning and repeat positioning accuracy of the machine tool spindle are greatly improved, thereby improving the overall measurement accuracy and processing efficiency of the CNC machine tool

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