GB449723A - An improved photographic developing machine - Google Patents

Abstract

449,723. Photographic developing- apparatus. RADIO CORPORATION OF AMERICA, 30, Rockfeller Plaza, New York, U.S.A. Aug. 20, 1935, No. 23378. Convention date, Aug. 31, 1934. [Class 98 (ii)] In a photographicdeveloping-machine, the space above the liquid in the developing tank is maintained at less than atmospheric pressure in order to eliminate excessive oxidation of the developing liquid. The film F passes into the tank 1, under an idle roller 2<1>, and upwards into the developing chamber 3, over an idle roller 4 supported from a float 5 in the liquid, and under a further idle roller 2 to the driving sprocket 10. At the upper end of each developing chamber are two pipes 6, 7 connected to manifolds 8, 9, the pipe 6 extracting liquid from the tank and the pipe 7 maintaining reduced pressure above the liquid and removing air or gas bubbles trapped by the film or produced during development. If the driving sprockets are normally immersed in the fluid, they are made of corrosion-resisting material. A single tank and a common supporting float may be used to accommodate the films during development. The rollers may also be on a single shaft. The tank 1 is preferably in the form of a hinged trough (Fig. 5) pivoted at 22 to a bracket 21 and held at the other side by a member 23 and catch 24. The tank can then be released and swung down to empty its contents into a trough 25 below and so permit scrubbing of the tank 1 and chambers 3.