Patent GB-1466318-A (GB)
Title: Method and apparatus for processing elongated photographic films
IPC: G03D3/13
Filed: 1974-09-10
Abstract: 1466318 Processing photographic films I MORI 10 Sept 1974 [29 Sept 1973] 39478/74 Heading G2X Films are processed by feeding the film to a film transfer unit 1 which moves the film sequentially through a developing bath 2, a fixing bath 3 and washing baths 4, 5 to a drying chamber 6, Fig. 1, the unit 1 comprising paired film feed rollers 100 ... 110, Fig. 2, which are first simultaneously rotated at a uniform speed until the leading end of the film reaches the last pair of rollers then stopped, and then reactuated sequentially in pairs at predetermined time lags to form loops of draped film successively in the baths. The unit 1 is driven by an electric motor 8 through gears 9, and film guides 111 ... 114 having freely rotatable guide rolls are provided with upwardly extending rods 115 ... 118 with conical flanges 123 ... 126 which are engageable with a control plate when the film feed rollers are simultaneously rotated at a uniform speed but which are disengaged from the control plate to lie on the film so as to drop by gravity when the film loops are being formed. The pairs of film feed rollers 101 ... 110 are biased towards each other by spring belts (131) extending round pulleys (129, 130) associated with the rollers, Fig. 3 (not shown). A control mechanism for the film transfer unit 1, Fig. 6, comprises a control plate 301, a spring- biased cam rod 302 with a ratchet 304 and a reciprocable rod 303 having a pawl 305 for engaging the ratchet, the rod 303 being spring-biased against a cam 309. A main driving gear 310 drives transmission gears 311 interconnected by idlers 312, the gears 311 being connectable to the film feed rollers 101 ... 110 through gears 313, a spline wheel (318), Fig. 7 (not shown), forming a sliding clutch being engageable with internal splines in each pair of the gears 311 and 313 when these are to be inter-connected. Each spline wheel is mounted on a a spring-biased longitudinally slidable shaft 314 carrying members (319) which pass through slots 327 in the control plate 301 and have projections 326 for engaging notches 330 ... 334 in the cam rod 302. Openings 322 in the control plate 301 receive the rods 115 ... 118 and have springs 323 for engaging the conical flanges 123 ... 126. A shaft 347 rotatable by a knob (346) has fixedly mounted on it an eccentric cam 328 for moving the control plate 301, and a cam 340 for controlling movement of the rod 303, and an arm 335 has rotational movement relative to the shaft 347 limited by pins 337 and 348. To set the mechanism for straight feed of the film the shaft 347 is rotated 90 degrees clockwise, Fig. 8 (not shown), whereby rod 303 is pressed by springs 344 and 345 to engage the pawl 305 with the ratchet 304. Arm 335 is rotated to move the cam rod 302 to the right and the control plate 301 is moved to engage the springs 323 with the conical flanges on the rods 115-118 and to engage all of the clutch spline wheels (318) so that the film feed rollers are driven synchronously, the projections 326 all engaging in their respective notches 330 ... 334 in the cam rod 302. To set the mechanism for forming the film loops the shaft 347 is rotated 180 degrees anti-clockwise, Fig. 10 (not shown), whereby the cam rod 302 is moved to the left with the projections 326 lying outside the notches 330 ... 334. The pawl 305 is engaged with the right hand end of the ratchet 304, the film guides 111 ... 114 are lying on the film, and the clutch spline wheels (318) are disengaged so that the film feed rollers cannot rotate. Upon actuation of the drive the cam 309 reciprocates the rod 303 which causes the pawl 305 to stepmove the cam rod 302 to the right to sequentially engage the projections 326 with their respective notches 330 ... 334 so as to cause sequential engagement of the clutch spline wheels (318) and so sequential rotation of the pairs of film feed rollers 101 ... 110. The mechanical control mechanism may be replaced by electrical control. The baths 2, 3, 4, 5 are fed through pipes 11, 12, 13 via circulating pumps 16, 17 and make-up valves 14, 15, and an overflow 18 is provided for the spent solution. An electric motor 20 drives a fan 21 supplying air to the drying chamber 6, the air flowing into the chamber 6 through passages 22 and out through a discharge 23. The film feed roller pairs may be staggered vertically. In another embodiment, Figs. 4 and 5 (not shown), the film guides are in the form of pairs of spaced plates each pair providing between them a slot for the passage of the film, the plates being movable between a horizontal position in which the film is straight fed through the film feed rollers, and a lower vertical position in which the film is led into the associated bath.