| 摘要 |
PURPOSE:To obtain a positioning member which does not cause deviation between a mechanical carriage position and an electrical control signal, is easy to control, and is prevented of malfunction owing to contact failure by providing an electric contact function to a mechanical contact for determining a reference position. CONSTITUTION:A carriage 2 is lifted and moved from a reference position to a desired position by a lifting member 8 which is driven by an electric motor 12. When this member 8 is lowered, the leading end part 15b of a sliding bar 15 for positioning descends together with the carriage 2 and abuts on the top surface 24a of a connecting bar 24 of a dustproof block, by which the reference position of the carriage is mechanically determined; at the same time, the leading end part 15b and the top surface 24a also provide an electrical contact function of the control circuit for the motor 12 and therefore to motor 12 stops and the carriage 2 is automatically positioned to the reference position. With this constitution, the positioning device which does not cause any deviation between the mechanical carriage position and the electrical control signal, is automatic, is easy to control and is prevented from malfunction owing to the contact failure by dustproof operation is provided. |
