Patent ID: 9175986
Filing Date: 2015-11-03
Classification: G01D

Abstract:
1. A separate linear encoder comprising: a scale provided with a main track; a detection head including a main detection portion to read the main track, and being relatively movable to the scale, an angle detection track arranged in parallel with the main track on the scale, an auxiliary detection portion to read the angle detection track, included in the detection head; a first calculation device to obtain a yaw angle of the detection head with respect to the scale based on a gap between the main detection portion and the auxiliary detection portion, and based on a difference amount between a position value of the main track detected by the main detection portion and a position value of the angle detection track detected by the auxiliary detection portion; a second calculation device to obtain a signal strength based on an output signal from the main detection portion; and a display device to display relationships between a plurality of yaw angles and signal strengths corresponding to the respective yaw angles.