| 摘要 |
PURPOSE:To decrease moment which guide means receives from a beam thereby to enable accurate linear traveling with decreased friction and wear, by interposing an elastic member between the beam and guide means. CONSTITUTION:A ball screw 11 and a motor 13 connected by a coupling 12 constitute drive means. A beam 10 and slide units 15, 16 engaged with guide means disposed on both sides of the beam 10 form a portal traveling member, wherein the units 15, 16 are adapted to travel along rails 21, 22 on a base 20. The slide unit 15 at one end of the beam 10 which is in a longer distance from the nut member 14 for the ball screw 11 is connected with the beam 10 by a plate spring 17 interposed therebetween. When the motor 13 is driven and a driving force is transmitted to the beam 10 by means of the rotation of the ball screw, the beam 10 is caused to travel, accelerate, or decelerate. Then, by virtue of the plate spring 17 interposed, a decrease magnitude of moment is excerted on the unit 15 or the rail 21. |
