Patent GB-1201469-A (GB)
Title: Apparatus for processing photographic material
Inventor: WOOLLACOTT DERRICK SUNNUCKS
IPC: G03D3/00
Filed: 1967-06-08
Abstract: 1,201,469. Photographic processing apparatus; time control of electric circuits. D. S. WOOLLACOTT, R.A. PARGETER, C.C. KEITH and D. EVANS. June 7, 1968 [June 8, 1967], No.26539/67. Headings G2A and G3T. Photographic Processing. Water, in a tank 1 and chemicals, in cylinders X, are selectively fed through solenoid-controlled valves 16, X1- X10 Fig.8 into a chamber 13; are pumped by a pump 102 up a feed pipe 24 into a removable, light-tight container, such as 33, Fig.4, containing film; and return to chamber 13 through a drain tube 25 for re-circulation. Liquid passes into container 33 through a tube 36, encounters film (not shown), and passes out through slots 42 and a light trap comprising slotted plates 35. For reversal processes, a conical reflector 59 is provided and a lamp housing 54, Fig.6 (not shown); illuminates through a window 48 on operation of a shutter 49. An alternative chamber 63, Fig.7 (not shown) has a spiral retainer (67) for roll film and another chamber 75, Fig.10 (not shown) has opposing slotted walls (77) to retain cut film or hangers Fig.11 (not shown) each supporting a roll film. A circuit Fig. 9 (not shown) maintains the temperature and water depth in tank 1 by means of solenoid-controlled hot and cold water valves (2, 3) and immersion heaters (4, 5), controlled by probes 6, 7, 8 and a thermometer (10). The valves X1-X10, 16 are selectively opened by microswitches M1-M10, M16 operated by cams on timer clocks T 1 -T 3 . In operation, valve 16 is opened and water flows into chamber 13, switching on the pump 102 when the level reaches a probe 23. The water may overflow through a tube 27. A timer (T 1 -T 3 ) then operates a microswitch (M1-10, 16) to switch off valve 16 and pump 102 and open a drainage valve 20. The timers repeat this process circulating each chemical and water (for rinsing) when required. When chemicals flow into chamber 13, the valves X1-X10 close when the level of chemical reaches a probe 26 (see also Fig.9). Time Control. Fig. 8 cams on timer clocks T1-T3 operate microswitches M1-M10, M16 (for selectively operating liquid supply valves X1-X10 and 16) and also operate microswitches TM1-TM5 such that at the end of its period of operation, each clock triggers the next clock. A switch S, determines which of the two identical circuits illustrated is energized. When starter button 110 energizes clock T1, a cam on the clock trips switch TM1 from A to B which deenergizes a relay R10 so that current flows to the switches M1-M5 and M16. Near the end of its period, clock T1 trips switch TM2 from C to D, thus starting clock T2 which trips switch TM3 from E to F. At the end of its period clock T1 trips switch TM1 back to B thus maintaining current flow to clock T2 when the latter trips switch TM2 back to C. Similarly, near the end of its period, clock T2 trips switch TM4 from G to H, thus starting clock T3 which trips switch TM5 from J to K. Thus when clock T2 finishes and trips switch TM3 back to E, clock T3 receives current via switches TM3, TM5. The microswitches M1 to M5 and M16 are selectively operated by cams on the clocks during this cycle.