ABSOLUTE ENCODER AND METHOD FOR GENERATING CURRENT POSITION OF ABSOLUTE ENCODER

摘要

PURPOSE:To prevent the positional deviation in the start-up of an encoder by monitoring the rotational speed in a circuit within an absolute encoder, prohibiting generation of the current position when the number of revolution is a prescribed value or over, and generating the prescribed value by the edge of a prescribed signal only one time when the number of revolution is the prescribed value or under. CONSTITUTION:When the prescribed value is preliminarily set by the edge of the bit of the lowest digit (six-bit here) of the resolution during the restoration, the maximum possible critical rotational speed 2 is set where no positional deviation is generated. The b6 edge setting impossible region 3 and the b6 edge setting possible region 4 are provided across this critical rotational speed 2 to monitor the rotational speed by the operating circuit of the encoder. At the points A1, B1 and C1, the data on the output position at the edge position are not reset, while at the point F1, the value equivalent to the edge position is reset as the data on the output position. The data on the output position are on the maximum resolution level from this time point. The data on the output position are not reset even at the point G1.