Photographic camera with contact arrangement in the accessory shoe and at other places of the camera

Claim 1

IN A PHOTOGRAPHIC CAMERA HAVING AN ELECTRICAL CIRCUIT ARRANGEMENT WITH A SHUTTER SYNSHRONIZING SWITCH INCLUDING A PAIR OF ELECTRICALLY CONNECTABLE POLES AND AN ELECTRICAL SOCKET INCLUDING A PAIR OF TERMINALS, EACH TERMINAL CONNECTED TO REPECTIVE SWITCH POLES, THE SOCKET HAVING MEANS TO RECEIVE THE CONNECTOR OF A FLASH ATTACHEMENT HAVING A LAMP IGNITION VOLTAGE TO APPLY THE VOLTAGE AT THE SWITCH POLES, THE IMPROVEMENT COMPRISING: (A) AN ACCESSORY SHOE IN THE CIRCUIT ARRANGEMENT AND INCLUDING AN ELECTRICALLY CONDUCTIVE BASE MEMBER CONNECTED TO ONE SOCKET TERMINAL AND THE RESPECTIVE SWITCH POLE, THE BASE MEMBER DEFINING A CENTRAL OPENING AND HAVING INWARDLY EXTENDING ENDS DEFINING RETAINING CHANNELS TO RELEASABLY RETAIN A CONNECTING FOOT OF A CAMERA ATTACHMENT, (B) A CONTACT MEMBER OF ELECTRICALLY CONDUCTIVE MATERIAL DISPOSED WITHIN THE BASE MEMBER OPENING AND ELECTRICALLY INSULATIVE MATERIAL SEPARATING THE CONTACT MEMBER AND THE BASE MEMBER, (C) A RESILIENT PLATE SPRING OF ELECTRICALLY CONDUCTIVE MATERIAL HAVING ONE END FIXED TO THE CONTACT MEMBER AND THE OTHER END DISPOSED BELOW AND SPACED FROM THE BASE MEMBER AT ONE CHANNEL, (D) AN ELECTRICAL LEAD CONNECTED TO THE OTHER SOCKET TERMINAL AND RESPECTIVE SWITCH POLE AND NORMALLY SPACED FROM THE SAID OTHER END OF THE PLATE SPRING TO INTERRUPT THE ELECTRICAL CIRCUIT TO THE ACCESSORY SHOE AND PREVENT VOLTAGE APPLIED THROUGH THE SOCKET FROM BEING EFFECTIVE AT THE BASE MEMBER AND CONTACT MEMBER, AND (E) A SLIDABLE, ELECTRICALLY INSULATIVE STUD FIXED TO THE SAID OTHER END OF THE PLATE SPRING AND HAVING A PORTION PASSING THROUGH THE BASE MEMBER INTO THE SAID ONE CHANNEL AND POSITIONED FOR DOWNWARD SLIDING MOVEMENT ONLY UPON USE OF THE ACCESSORY SHOE BY INSERTION OF AN ACCESSORY FOOT TO MOVE THE SPRING INTO ENGAGEMENT WITH THE LEAD AND ELECTRICALLY CONNECT THE CONTACT MEMBER WITH THE OTHER SOCKET TERMINAL AND RESPECTIVE SWITCH POLE, THEREBY COMPLETING THE CIRCUIT FOR THE ACCESSORY SHOE AND APPLY VOLTAGE TO THE BASE MEMBER AND CONTACT MEMBER ONLY WHEN THE SHOE IS BEING USED.