Title:
SWITCH ON/OFF CONDITION DETECTING DEVICE
Document Type and Number:
Japanese Patent JPH01166425
Kind Code:
A
Abstract:
PURPOSE:To prevent an error detection of switch ON/OFF condition by composing the device with a power circuit for detection, a breaking device of the current flowing in a DC voltage through this circuit, and a current detecting device to detect the ON/OFF condition by detecting a current from a detection voltage. CONSTITUTION:This detecting device is composed of a diode 5, a cell 6, a photocoupler 7, and resistances 8 and 9 to limit the current. The cell 6 is to apply a voltage to detect the opening and closing condition other than a DC voltage applying from a low voltage power source circuit 1 to an interlock switch 2, and the diode 5 and a luminous diode 7a break the current flowing from the diode 5 through the circuit of the resistance 8 by the output voltage of the low voltage power source circuit 1. And the photocoupler 7 detects the opening and closing condition of the switch 2 by detecting the current flow by the voltage of the cell 6 responding to the ON/OFF condition of the switch 2. In such a composition, the ON/OFF condition of the switch 2 can be detected directly accurately, and the trouble of error detection is eliminated.
Inventors:
KUSANO AKIHISA
Application Number:
JP32271587A
Publication Date:
June 30, 1989
Filing Date:
December 22, 1987
Export Citation:
Assignee:
CANON KK
International Classes:
H01H9/54; (IPC1-7): H01H9/54
Attorney, Agent or Firm:
Kato Taku