| 摘要 |
PURPOSE:To adjust easily the position, speed and pressing force of the plunger with very good precision and to enable to always perform a resin sealing of high quality by a method wherein the plunger is made to drive by the motor and a resin is injected and pressed. CONSTITUTION:When a plunger motor 50 is made to revolve, the turning force thereof is transmitted to a ball screw 43 through a bevel gear pair 50b and 43a and a nut 42a to screw in the ball screw 43, that is, a plunger 42, is made to ascend. Accordingly, a resin 41 to be placed on the upper part of the plunger 42 is injected on the lead frame be placed at the prescribed position on a bottom force 15. At this time, as a constant torque limitation is being made on the side of the motor 50, the plunger motor 50 stops its revolution when the pressing force of the plunger 42 reaches the prescribed pressure. There, the stop of revolution of the plunger motor 50, that is, the stop of the plunger 42, is detected and a resin sealing of the top and bottom forces is performed while the pressing force of the plunger is held for a constant time from the point when the stop of the plunger is detected. |
