| 摘要 |
PURPOSE:To eliminate the response delay to use the two-wire photoelectric switch for AC and DC, by connecting the connection point between the transistor and the constant-voltage element to the light projecting and receiving circuit side of the current limiting resistance and by providing a diode bridge between power supply lines. CONSTITUTION:When the output signal becomes ''H'', transistors 17 and 20 are turned on, and a current is flowed through transistor 20, and therefore, a large current is flowed to load 23. Meanwhile, since a sufficient current cannot be supplied to light projecting and receiving circuit 20 through resistance 14, a current is supplied to light projecting and receiving circuit 10 and capacitor 13 directly from the cathode of the Zener diode through no resistance 14. When the output signal becomes ''L'', transistors 17 and 20 are turned off immediately. Since diode bridge 21 and smoothing capacitor 13 are provided, this switch is used for the AC power source as well as the DC power source. |
