GB1156463A - Improvements relating to Photographic Processing apparatus - Google Patents

Abstract

1,156,463. Photographic processing apparatus; cameras. INTERNATIONAL POLAROID CORP. Nov.22, 1966 [Nov.26, 1965], No.52277/66. Heading G2A. A camera with built-in processing apparatus producing colour prints by diffusion transfer is closely similar to the type disclosed in Specification 1, 156, 464, a photo-sensitive imagerecording sheet 52 being fed by guide 143 and driven rollers 140,142 to follow a U-shaped path through processing liquid 98 while, after a delay, an image-receiving sheet 54 is fed by roller 149 and curved guide 148 to deflect and contact the end of sheet 52 issuing from liquid 98 whereby the two sheets are drawn through and compressed by rollers 144, 148. Sheets 52, 54 are stored in two face-to-face stacks in pack 50, sheets 52 being advanced from the pack by shoes 114 having plastics foam surfaces to frictionally engage the foremost sheet. The shoes are carried on arms (116, Fig. 4, not shown), pivoting on a shaft (118) mounted between brackets (120) slidable on tracks (122). In the disengaged position, ends (126) of arms (116) are pressed against members (127) to raise the shoes against spring (124). Rotation of hand-crank (46) slides brackets (120) along their tracks through links (128) and a gear and lever system, and the shoes advance one sheet. Rotation of crank (46) also makes the exposure and starts the processing cycle, the end of the stroke switching on electric motor (160) driving the rollers and cams of a control system, Fig. 3 (not shown). Cam (159) pivots arm (152) through push-rod (156) whereby friction-plate (82) is displaced downwardly to advance one imagereceiving sheet (54). The period of processing in liquid 98 is variable by changing the motor speed, or in a manually-driven version, by adjusting the speed governor. To ensure operation of the camera in an upright position only, a position-sensitive switch is included in the motor circuit. The batteries may operate a heater for temperature control of liquid 98 and may also operate a timer giving a signal when the sheets 52, 54 may be separated. In a modification, curved guide 148 is of deformable plastics and presses sheet 54 into driving contact with roller 149 when released from a disengaged position by a cam-operated tripping arm when the sheet reaches a predetermined position.