| 摘要 |
PURPOSE:To enable a ventilating roof to be controlled easily and securely by an user by providing an electronic by-pass switch stage so as to by-pass a position switch automatically for drawing a cover from a prescribed cover position when a manual switch device operates. CONSTITUTION:At the closing position of a cover 17 with a switch SS open, switches S1 and S3 are in a switch position 0, and a switch S2 is in a position 1. When a manual switch SR is closed, positive potential of the positive pole of power supply 33 reaches an input 35 of a by-pass switch state 34 through the switch SR and the position switch S3. Thus, a series circuit which consists of a capacitor C1 and a resistor R1 and forms the dynamic input circuit of the switch stage 34 sends a short positive pulse to the base of a transistor T1 as a set signal. T1 output is formed with LOW coupled to the input of a transistor T2 through a resistor R7. On the other hand, T2 output is formed with High reaching the base of a T3 through a resistor R6, so that T3 is conducted and an electric motor 18 rotates. |
