Electronic photoflash unit having remote control device transmitter function

Claim 1

An electronic photoflash unit having functions as a remote control light transmitter and as a photoflash for flash photography, comprising: a flash discharge tube; a main capacitor for providing a discharge current to energize said flash discharge tube; a trigger circuit connected to trigger the energization of said flash discharge tube causing discharge by said main capacitor; a switching circuit connected to deenergize the radiation from the flash discharge tube; a delay circuit selectively connected for actuating said switching circuit after a regulated time interval measured from the initiation of radiation from said flash discharge tube; interlocking switch means provided in one of said switching circuit and said delay circuit, and having contacts for permitting the operation of said switching circuit by the output of said delay circuit when said photoflash unit is dismounted from said camera and for preventing the operation of said switching circuit by the output of said delay circuit when said photoflash unit is mounted on said camera; and an accessory shoe having a slidable insulator member which is spring loaded outwardly thereof, wherein the accessory shoe is receivable in an accessory clip on a camera, and wherein said contacts of said interlocking switch means are separated from said slidable member and disposed in a closed position when the accessory shoe is disconnected from the accessory clip, and, when the accessory shoe is fixed in the accessory clip, said slidable member is displaced so as to engage with said interlocking switch means to hold said contacts in an open position.