| 摘要 |
PURPOSE:To obtain a high preciseness length measuring apparatus, by fixing a length measuring scale to the mount reference surface formed to a case under pressure by an elastic member through a lubricating member. CONSTITUTION:A lubricating member 3 is inserted between a length measuring scale 1 and a case 2, and the scale 1 is pressed and held to the mount surface 6 of the case 2 in the side opposite to the member 3 by the elastic member 4 provided between the scale 1 and the case 2. A detection head 8 has the light source provided to one graduation surface of the scale 1 and the index scale and light receiving element provided to the other graduations surface thereof and is constituted of a detection part 8a moving to the direction vertical to the surface of paper in opposed relation to the graduations surface, the base part 8b fixed to the other 11 of an article to be measured and the arm part 8c connected the detection part 8a and the base part 8b. When temp. change is generated, the length of the scale 1 changes but the scale 1 slides along the surface of the member 3 and receives no effect of the case 2. Therefore, measuring accuracy becomes stable. |
