GB152539A - Improvements in and relating to photographic cameras - Google Patents

Abstract

152,539. Terwiel, G. J. Nov. 26, 1919. Cameras with connected action between shuttcr and changing-mechanism. - Relates to cameras provided with means to prevent re-setting of the shutter till a new section of film is in position, the film then being locked till the shutter is operated. A locking pawl device with four arms 10, 11, 12, 13 is mounted on a stud screw 9 fixed to the casing, the arm 13 engaging in perforations 26 in the film and arm 12 engaging a ratchet-wheel 8 coupled to the unwinding-speol by means of pins. The arm 11 is actuated by a Bowden-wire connexion 15 to a push-button 20 to move arms 12, 13 out of engagement; the arm 10 then engages a latch 14 and can only be disengaged by winding up the film till a pin 8<a> on the ratchet 8 trips the latch 14. This allows arm 13 to press on the film so that arms 12 and 11 and consequently the push button 20 do not return to their original positions till the next perforation in the film comes under arm 13. The shutter is operated by a second Bowden-wire connexion 24 to the push-button 20 so that a further exposure cannot be made till the new film section is in position, since, till this is done, the button is in the depressed position.