| 摘要 |
<p>1,139,000. Multiple flash bulbs. PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd. June1, 1967 [June 4, 1966], No.25266/67. Heading G2L. [Also in Division H1] In a flash unit for successively firing a number of flash bulbs in which the firing of one bulb actuates a switch to make the next bulb ready for firing, each switch is spaced from the surface of the associated lamp and comprises a switching member which becomes low-ohmic solely as the result of the radiant heat produced by firing the lamp, and connects the electrodes of the switch to make the next lamp ready for operation. The unit consists of a flat casing enclosing the bulbs in recesses, a reflector formed as a single unit and a transparent cover. All the lamps are connected to a common lead 35, Fig. 3. The first lamp 15 is connected to a second lead 65 and the succeeding lamps 17-23 to leads 49-55 connected through switches 57-63 to the lead 65. In one form of switch, the leads 47-65 provided with parts 75, Fig.4 of low melting point metal e.g. Wood's alloy, Lipowitz alloys, Newton alloys or Rose alloys, separated by an insulating layer 77, e.g. of colophony, from a similar metal strip 79. The heat of firing of the bulb melts the parts 75, 77, 79 bridging the leads 49, 75. In a modification, the leads are connected by a compound of a noble metal, e.g. silver oxide, in an organic binder, e.g. polyvinyl resin, which is decomposed by the heat of firing the bulb to form a conducting metal layer.</p> |
