GB1034563A - Improvements in or relating to photographic developing apparatus - Google Patents

Abstract

1,034,563. Photographic developing apparatus. W. ZINDLER. March 18,1964 [April 1, 1963], No. 11455/64. Heading G2A. [Also in Division G1] A photographic developing apparatus has means for guiding a photographic sheet along the liquid surface so that only one side is wetted, the apparatus also having a constant liquid level arrangement comprising a supply container connected to both the bath of liquid and to a reserve tank. In the form shown, the bath 1 containing the developing liquid has a number of web members 6 extending across its lower part. The generally flat upper edges 15 of these webs define the position of the liquid surface. Photographic sheets to be developed are fed into an inlet 2, whence they are guided across webs 6 so that they are wetted on their under side only. They are then guided out of the apparatus through an outlet 3 and between transport rollers 4, 5. If a transfer process is to be effected, a second inlet 28 is provided, through which a copy sheet can be inserted and passed below the bath 1, so that it has a completely dry path until it meets the negative and they are pressed together between rollers 4, 5. A supply container 8 is provided within the bath 1, its walls 9, 10, 11 being parallel to the bath and web members. A short pipe 12 extends downwards from the base 11 to below the liquid level in the bath. Another pipe 13 extends downwards to just above the edges 15 of the web members, and upwards into the supply container 8 almost to its top wall 17. A much wider pipe 19 connects the lower part of the container 8 to a reserve tank 20 situated below the apparatus. A connecting pipe 26 joins pipe 19 directly to the bath. Tank 20 is flexible, and can be compressed by a movable plate 23. When plate 23 is raised, tank 20 is compressed and the liquid forced upwards into both container 8 and bath 1. As soon as the liquid level in the bath reaches the bottom of pipe 13 it can rise no further. During use, if the liquid level of the bath falls slightly due to the amount carried away by the passage of the film sheets, it is automatically restored by replenishing liquid from the full supply container 8. When use of the apparatus is no longer required, plate 23 is lowered again, and the liquid flows back into tank 20 through both pipes 19 and 26, so that container 8 and bath 1 are both completely empty.