| 摘要 |
PURPOSE:To uniformly apply a pressure even when a posture is changed and to enhance the reliability of connection strength by using a rotary pair which does not generate a restoring force even when the posture is displaced due to a centering operation ot a remote centering mechanism. CONSTITUTION:Bearings are used for rotary pairs 10-13 so that the pairs cannot generate a restoring force of a spring. Accordingly, if a parallel error exists between a die 18 and a base 5, the die 18 is turned around a center O structurally, and the parallel error is adjusted automatically. However, when the center of gravity 21 of a centering mechanism is displaced from a vertical line of the center O due to a change in a posture, the die 18 is tilted to a mechanical limit position if the die 18 is not brought into contact with the base 5. As a method to offset a moment due to the center of gravity and to maintain an initial posture of the die 18, an electric current is impressed on coils 27, 28 from an electric-current control circuit 23 in a state that the die is not pressurized; a balance of force is established at the center due to an action of a magnetic force of the coils 27, 28 and a magnet 29; when the die is tilted, a restoring force is actuated strongly; as a result, the initial posture can be maintained. By this setup, it is made possible to execute a more uniform pressurization operation. |
