| 摘要 |
1437034 Flashing lamp intensity control EXXON RESEARCH & ENG CO 14 May 1973 [17 May 1972] 01717/76 Divided out of 1437033 Heading G1A A flashing lamp control arrangement comprises lamp means 1, 2 emitting light at two intensity levels (i.e a single dual-filament lamp or two separate lamps), a pulse generator 3 arranged to intermittently supply power to the lamp means to cause flashing thereof, a photo-conductive detector 5 monitoring the ambient light level and causing a transistorized switching circuit 4 to switch the lamp means to the high intensity level when the ambient level rises above a predetermined threshold (i.e. during the day) and to a low intensity level when the ambient level is below the threshold (i.e. during the night). The pulse generator may be an oscillator or an astable multi-vibrator as detailed in Fig. 2 (not shown). Detector 5 may be a Cd S or Cd Se device. |
