A pair of fixed arc electrodes (30a), (30b) are arranged facing each other within a sealed container that is filled with arc-extinguishing gas 1. There are provided: a compression puffer chamber (12) for accumulating pressurized gas (35) that is obtained by elevating the pressure of the arc-extinguishing gas (1); and an insulated nozzle (32) that directs the pressurized gas (35) towards the arc discharge (7) from the compression puffer chamber (12). A buffer chamber (36) is provided, in which hot exhaust gas (20) generated by the heat of the arc discharge (7) is temporarily accumulated. A pressurized gas through-flow space (43) is provided, communicating with the compression puffer chamber (12) . In the pressurized gas through-flow space (43), an opening/closing section (41) prevents inflow of hot exhaust gas (20) by assuming a closed condition during the earlier half of the current interruption period, and in the latter half of the current interruption period the opening/closing section 41 is opened to allow flow of pressurized gas (35).

Gas-blast circuit breaker

PURPOSE:To reduce impact force by stepwise applying writing pressure power when writing pressure is applied to a pencil pen. CONSTITUTION:When a pencil pen 1 is present at an landing point, stepwise writing pressure power rising gradually is applied and, at first, writing pressure power about half power obtaining desired writing pressure is applied. At this time, the impact force to the pencil pen 1 becomes intstantaneously large but it becomes far smaller than that of a conventional apparatus and, thereafter, predetermined writing pressure power D is applied in order to obtain proper writing pressure. As a means for applying writing pressure power, an ROM storing a predetermined writing pressure applying pattern is provided in a control circuit 4 and a processor reads the stored program of the ROM and controls the pen up-and-down moving circuit and actuator 32 of the next stage to apply writing pressure. By this method, the impact force received by the pencil pen 1 is reduced.

Morigami Keigo

Papers

Buffer gas breaker