MULTI-TURN ABSOLUTE ENCODER, METHOD FOR DETECTING ROTATION SPEED OF MULTI-TURN ABSOLUTE ENCODER, AND COMPUTER RECORDING MEDIUM RECORDING SAME

摘要

The present invention discloses a multi-turn absolute encoder and a method for detecting the rotation speed of a multi-turn absolute encoder. The multi-turn absolute encoder according to the present invention includes a gear including a main shaft and at least one minor shaft having teeth engaged with the teeth of the main shaft, at least one magnetic sensor detecting a change in the magnetic force of at least one bipolar magnet provided on each of the main shaft and the at least one minor shaft, a database storing a lookup table index-indicating the relationship between the rotation speeds of the main shaft and the at least one minor shaft in a range of the least common multiple of the number of teeth of the main shaft and the number of teeth of the at least one minor shaft, an angle detection unit calculating an absolute angle of each shaft by a triangle wave by using the magnetic force change detected by the at least one magnetic sensor as each shaft rotates, a minor shaft rotation speed detection unit detecting the rotation speed of the at least one minor shaft by using the magnetic force change detected by the at least one magnetic sensor, and a main shaft rotation speed calculation unit detecting the absolute angle at a specific time point of each shaft from the triangular wave, detecting the relative rotation speed of the main shaft from the relationship with each minor shaft by using the number of gear teeth of each shaft and the absolute angle at the specific time point of each shaft, and detecting the absolute rotation speed of the main shaft from the lookup table by using the detected main shaft rotation speed as an index. According to the present invention, the relative rotation angle of the main shaft is calculated stepwise, and thus the relative rotation speed of the main shaft can be easily obtained. As a result, it is possible to easily calculate the absolute rotation speed of the main shaft and the index of the lookup table.;COPYRIGHT KIPO 2018