Title:
OVER-LOAD DETECTING APPARATUS AND INCANDESCENCE LAMP CONTROL APPARATUS
Document Type and Number:
Japanese Patent JP3300173
Kind Code:
B2
Abstract:
PURPOSE: To provide an over-load detecting apparatus and an incandescence lamp control apparatus which can detect an overcurrent by cancelling variation of an input power supply voltage through detection of over-current through a DC circuit.
CONSTITUTION: A momentary value of a commercial power supply voltage 1 is detected with a momentary value detecting circuit 2 and a load current i is converted into a voltage by a current transformer 6 and is then guided to an over-current detector 3. The over-current detector 3 detects an over-current depending on that an output voltage v of the current transformer 6 is equal to or higher than the threshold value vth or not when the momentary value has reached the predetermined voltage and outputs the result to a phase control circuit 7. In the phase control circuit 7, a gate control signal is outputted to a triac 5 so that an incandecence lamp 4 controlled to light with a half-wave when the over-current is detected.
Inventors:
Yukinobu Ogawa
Koichiro Sakai
Koichiro Sakai
Application Number:
JP24639894A
Publication Date:
July 08, 2002
Filing Date:
October 12, 1994
Export Citation:
Assignee:
Kuroi Denki Co., Ltd.
International Classes:
G01R19/165; G05F1/10; G05F1/455; H02H9/02; H05B39/04; (IPC1-7): H02H9/02; G01R19/165; G05F1/10; G05F1/455; H05B39/04
Domestic Patent References:
| JP62100666A | ||||
| JP7272869A |
Attorney, Agent or Firm:
Hisao Komori