US3517600A - Apparatus for processing photographic materials - Google Patents

Description

J1me 1970 b. s. WOOLLACOTT 3, 1

APPARATUS FOR PROCESSING PHOTOGRAPHIC MATERIALS 7 Sheets-Shae? 1 Filed June 5. 1968 lnvenlor LERRIQK SUN NVCKS (1)4) 01+ B 5T1- y Attorneys June 30, 1970 D. s. WOOLLACOTT 3,517,500

APPARATUS FOR PROCESSING PHOTOGRAPHIC MATERIALS 7 Sheets-Sheet 2 Filed June 5. 1968 Inventor --x4 --x5 x2 05R 11 LK SUN fink/ 5 LOLRDLL A 607'? y 4n, v- Attorneys June 30, 1970 D. s. WOOLLACOTT 3,517,500

APPARATUS FOR PROCESSING PHOTOGRAPHIC MATERIALS Filed June 5, 1968 7 SheetsSh eet 5 Inventor DER!!! SUA/A/UC/KS we ACO TT MM 5% MM v Attorneys June 30, 1970 D. s. WOOLLACOTT APPARATUS FOR PROCESSING PHOTOGRAPHIC MATERIALS Filed June 5. 1968 7 Sheets-Sheet 4 Inventor OHM/ck Sumw zs UJOOu/QQOTT a." Home y 5 Mai June 30, 1970 o. s. WOOLLACOTT 3,517,600

APPARATUS FOR PROCESSING PHOTOGRAPHIC MATERIALS )i'afmheJai /076 lnvenlor Dam/m S g/WW5 Luca/mow tlorneys June 30, 1970 D, s. WOOLLACOTT 3,517,600

APPARATUS FOR PROCESSING PHO'I'QGRAPHIC MATERIALS Filed June 5. 1968 v Sheets-Sheet e fig-i- Invenlor DERRICK SWMKS Maw/m7? y MM,

Uorne y s APPARATUS FOR PROCESSING PHOTOGRAPHIC MATERIALS Filed June 5, 1968 June 30, 1970 D. s. WOOLLACOTT 7 Sheets-Sheet '7 I nvenlor I DERfl/Gk Sumucxs woumrr' y r Attorneys United States Patent APPARATUS FOR PROCESSING PHOTOGRAPHIG MATERIALS Derrick Sunnucks Woollacott, Kent, England, assignor to Derrick Suuuucks Woollacott, Kent, Roland Albert Pargeter, Hove, Sussex, Charles Christopher Keith, Lingfield, Surrey, and David Evans, London, England Filed June 5, 1968, Ser. No. 734,781

Claims priority, application Great Britain, June 8, 1967,

Int. Cl. G03d 3/06 US. Cl. 95-89 13 Claims ABSTRACT OF THE DISCLOSURE An apparatus for processing photographic material such as prints or film. The material is placed in a lightproof container which is fitted onto the remainder of the apparatus, a vertical feed pipe extending upwardly in the container. When the apparatus is switched on, water and chemicals which are maintained accurately at the desired temperature and pumped in turn up the feed pipe, strike the top of the container and cascade over the material, are returned to the pump and recirculated.

The present invention relates to a method and apparatus for processing photographic materials, such as prints, films or transparencies and is particularly concerned with an apparatus for processing in a relatively inexpensive manner a single black and white or colour print, or small runs of a few such prints.

Previously it has been necessary either to carry out the necessary chemical reactions on photographic prints by placing them by hand in various dishes of treating solution, in a dark room, by feeding them through an expensive semi-automatic drum-type treatment apparatus, or using a continuous automatic processing machine. For this reason, one off colour prints tend to be extremely expensive.

It is an object of the present invention to overcome the above disadvantages.

According to the present invention, there is provided an apparatus for processing photographic sheet or film material, such apparatus comprising a processing chamber, a light-proof container for the material releasably mountable on said processing chamber, a pump communicating with said processing chamber, a feed pipe connected to the outlet of the pump, and extending substantially vertically upwardly with it open upper end located a short distance below the upper interior surface of the container, a drain to the light-proof container adapted to return liquid from the container to the processing chamber for recirculation and means for selectively feeding chemicals and rinsing water at a desired temperature, to said processing chamber.

While the apparatus is particularly suitable for processing prints, by forming the processing container suitably, the apparatus can be used to process roll film, sheet film and transparencies and the container may be fitted with a lighting arrangement to carry out colour reversal in the container.

It will be appreciated that it is necessary only to insert the photographic material into the container in the dark room, and the container may then be brought into the light and fitted to the processing chamber, and the remainder of the processing effected in the light.

In order that the invention may more readily be understood, the following description is given, merely by Way of example, reference being made to the accompanying drawings, in which:

3,517,600 Patented June 30, 1970 FIG. 1 is a perspective view of one embodiment of apparatus according to the invention;

FIG. 2 is a schematic part side elevation in section of this embodiment of apparatus;

FIG. 3 is a part section on the line IIIIII of FIG. 2;

FIG. 4 is a section through one form of container securable to the apparatus of FIGS. 1 to 3;

FIG. 5 is a top plan view of the container of FIG. 4;

FIG. 6 is a light source attachment for the container of FIGS. 4 and 5;

FIG. 7 is a section through an alternative form of container;

FIG. 8 is a circuit diagram of the programming circuit of the apparatus;

FIG. 9 is a circuit diagram of the heating apparatus;

FIG. 10 is a perspective view of a further form of container; and

FIG. 11 is a solid hanger for use in the container of FIG. 10.

Referring now to FIGS. 1, 2 and 3 of the drawings, the apparatus illustrated therein comprises a tank 1 preferably formed of a plastics material, the tank containing ten vertically extending cylindrical vessels X. In order to fill the tank with water, the latter is provided with a cold water inlet pipe 1A and a hot water inlet pipe 13. The tank is further provided with an overflow 1C. The flow of water through the pipes 1A and 1B is controlled by solenoid operated valves 2 and 3 respectively, and also by stop cocks 1.1 and 12 respectively.

At the lower end of the tank 1 are two electrical immersion heaters 4 and 5, one of these being a one kilo watt heater and the other a two kilowatt heater. Within the tank there are mounted, to extend to various depths,

three electric probes 6, 7 and 8. Also mounted in the I,

tank is an electrical agitator 9 and an electric contact thermometer 10. Extending downwardly from the bottom of each of the vessels X is a chemical supply pipe each of these supply pipes including an electrically operated solenoid 'valve X1, X2 X9, X10. When one of these valves X1, X2 X9, X10 is open, it will supply liquid chemical from the associated vessel X to a chute 14. Also extending into the top of chute 14 is a wash supply pipe 101 which is provided with an electrically operated solenoid valve 16. When this valve is open, water from the tank .1 flows to a distributor pipe 15 and to a conduit 30 to be described later. The distributor pipe 15 is generally U-shaped in plan, as can be seen from FIG. 3, and is perforated at its lower edge so that the whole of the chute 14 is washed with water when the valve 16 is open.

As can be seen from FIGS. 2 and 3, the chute 14 disgorges into a processing housing 13, a baffie 17 being arranged to cause the solution of water to swirl around the cylindrical wall of the housing 13 in an anticlockwise direction as viewed in FIG. 3. The bottom wall of housing 13 slopes downwardly away from the chute towards a pump housing or sump 18 and liquid therein can flow firstly to a pump 102, secondly to a waste valve 20 and thirdly into a probe housing 19. A process housing overflow 27, the upper end of which extends above the top of pump housing 18, opens downwardly into a common drain with a drain pipe 29, connected to drain valve 20.

Mounted within the probe housing 19 are a common probe 21 at the lower end of the probe housing, and three probes 22, 23 and 26 which extend to ditferent levels within the housing. Their height can be adjusted by grub screw clamps held by the cover 32 of housing 19. As can be seen from FIG. 3, this cover 32 includes a three-legged slot 32A which has one leg extending between each adjacent pair of probes, to reduce any electrical leakage caused by condensation on the lid. At about its mid-height,

the probe housing 19 includes a flushing pipe 31, which is connected by means (not shown) to the conduit 30 referred to earlier. Flushing pipe 31 extends around the interior of the probe housing 19 and is provided with apertures so that flushing water can flow down the inner walls of the probe housing 19 when valve 16 is open.

Liquid pumped by pump 102 flows upwardly through a feed pipe 24 which is concentrically arranged with respect to a drain tube 25, feed pipe 24 and drain tube 25 extending to just above the level of a processing deck 103. Drain tube 25 extends to the bottom of the processing housing 13 and is provided with a cut out portion 28 located at the angular position thereof opposite the processing housing overflow 27. Centering of the tube 24 in the tube 25 is effected by a spider 24A which carries, around feed tube 24, a gasket 41.

Turning now to FIG. 4, there is illustrated a first form of processing container 33 which comprises a vertical cylindrical outer wall having a concentric intermediate tube 34 centered therein by a downwardly convergent annular wall 38 and a lower annular disc 39. A concentric inner tube 36 is centered in the container 34 by the upper wall 37 of intermediate tube 34, and by three discs 35. Each of these discs is provided with diametrally opposite slots 35A, the slots 35A of the central disc 35 being offset by 90 with respect to those of the upper and lower discs. Immediately above the annular wall 38, intermediate tube 34 is formed with drain slots 42. When the container 33 is in daylight, light is precluded from entering the interior through the bottom of intermediate tube 34 by the positioning of the slots in discs 35 and the positioning of the slots 42. At its lower end, inner tube 36 is surrounded by a sleeve 40, which abuts the lower disc 35, and is of a diameter to fit snugly over feed pipe 24, the cylindrical outer wall of container 33 engaging within drain tube 25.

At its upper end, container 33 is provided with a downwardly divergent peripheral rim 45 over which clip legs 44 of a container lid 43. Extending between the upper annular wall of lid 43 and an inner annular wall 43A is an annular gasket of compressible material. The upper surface of the lid is provided with a pivoted lifting handle 53 and an annular groove 55, while a window 48 in the centre of the lid may be closed by a shutter 49, which pivots about a pin 50, and is constrained in its movement between a fully open position, when a locating pin 51 is at one end of a slot 52, and a fully closed position, when the locating pin is at the other end of such slot (see FIG.

Mountable on top of the lid 43 is a light housing 54, the lower edge of which can engage in the groove 55. Housing 54 has a mounting for a photoflood lamp 60, the upper wall of the housing 54 including ventilation holes 58. Light is prevented from passing in or out through these ventilation holes by two discs 56 and 57.

For certain purposes, a conical reflector 59, having a central tubular stem 59A may be positioned within the container 33 by slipping the stem 59A over tube 36 so that its lower end abuts the upper wall 37 of intermediate wall 34. Reflector 59 is graded from black at the apex to white at the base, and this grading may be done with black rings painted on its surface, the rings being closer together at the apex and being spaced further apart nearer the base.

In FIG. 7 there is illustrated a further form of container suitable for the treatment of roll film. This container 63 is substantially cylindrical and is provided with a removable lid 62. The lower wall of the container 63 has a central aperture in which is located a vertical annular weir 68. Mounted by means of a spider 70, within the annular weir 68, is a sleeve 69 similar to the sleeve 40 of the container of FIG. 4, this sleeve 69 again being of a size to engage snugly over the upper end of feed tube 24, while the lower end of annular weir 68 can engage within drain tube 25 when the housing 63 is lowered onto the processing deck 103.

Removably mounted within the container 63 is an assembly comprising a vetrically extending feed tube 61 which is open at the top and bottom, and is surrounded by a bleed tube 66 open only at its bottom, this in turn being surrounded by an open bottomed syphon tube 64. Immediately above the top wall of syphon tube 64, the bleed tube 66 is provided with bleed holes 65, while a spiral 67 extends outwardly from the side wall of syphon tube 64. The spiral 67 consists of two horizontal walls provided with facing spiral ribs, and below the spiral is an annular block 71. If desired, the lid 62 may be provided with a movable shutter and detachable light source as previously described with reference to FIGS. 4, 5 and 6.

In the operation of the above described apparatus various processing chemicals are loaded in solution into the containers X in tank 1. The tank 1 is filled with water and is maintained accurately at the desired temperature by firstly adjusting the flow through the cold and hot inlet valves 2 and 3 and also by use of the heaters 4 and 5 as desired. As will be described later, water is repeatedly drawn off from the tank 1 through water supply pipe 101 and this water has to be replenished and at the same time has to maintain the temperature in the tank at the desired value, the circuit for effecting this control being illustrated in FIG. 9. Current is taken from a transformer 104 and is rectified by a full wave rectifier 105 having a large smoothing capacitor 106 connected across its output terminals. The negative terminal of the rectifier is connected to the common probe 6 in tank 1 and the common probe 21 in probe housing 19. Contacts 7 and 8 in tank 1 are connected to contact R4A of a relay R4 which is operated when the level of water in tank 1 is above probes 7 and 8 via a transistor TR4.

The thermometer 10 is of a standard construction and includes a control arrangement 107 which is such that if the temperature of the water in the tank 1 falls below a predetermined value, the heater 4 is connected in the circuit, and when the temperature rises to the maximum desired value, the heater 4 is disconnected and an indicator light 108 shows that the water in tank 1 is of the desired temperature. Connected across the heater 4 and indicator light 108 are the coils of hot and cold water inlet valve 3 and 2 respectively, these being connected via the heavy duty contacts RSA and RSB of a relay R5, which is operated by contact R4B when relay R4 is itself not operating. Relay R5 also includes a contact R5C which closes and opens the circuit to the motor of the stirrer 9. Thus, if the water level in tank 1 falls below the level of probe 7, transistor TR4 ceases to conduct and the contacts R4A and R4B open to the position illustrated in FIG. 9. This de-energises relay R5, so that its contacts are in the position illustrated in the figure, and water is drawn into the tank 1 via valve 2 or valve 3, depending upon whether the temperature in the tank sensed by thermometer 10 is above or below the desired value. At the same time the stirrer 9 is operated to stir the water in the tank 1. When the water reaches the level of probe 8, transistor TR4 conducts so that relay R4 closes its contacts thus shutting off valve 2 or valve 3 and stopping operation of the stirrer 9. Since one contact R4A effectively connects probes 7 and 8, transistor TR4 will conduct until such time as the level again drops below probe 7.

A separate control circuit to be described later opens the valves X1, X2 X9, X10 and valve 16, in turn,

as prescribed by a preset programme, so that chemical solution or water falls through chute 14 into the processing housing 13. When the level in this housing is sufiiciently high to control probe 23, current passes via transistor TRl to operate relay R1, to close contact RlA which operates the pump 102, and to close contact RlB which locks in the lowermost probe 22 in probe housing 19'. When the level of liquid in housing 19 reaches probe 26, current is fed via amplifier transistor TR2 to operate a relay R2. When this is operated, its slave relay R3 is actuated, this disconnecting the solenoid operated valves X1 to X10 and 16. With the pump operating, the level within the probe housing 19 may well fall again as the liquid is forced up feed tube 24 into the container 33. In order to prevent the pump from running dry, transistor TR2 and therefore relays R2 and R3 will be disconnected if the level falls below probe 26, thus allowing valves X1 to X10 and 16 to open to supply more chemical or water to the processing housing 13.

Turning now to the control circuit illustrated in FIG. 8, there are illustrated two identical circuits which are connected to the mains alternatively, depending upon the position of the selector switch S1. In order to save repetition, only one of these circuits need be described. Assuming therefore that the selector switch S1 is in the uppermost position, the circuit on the left will be connected to the mains. When these circuits are completed through switch S2, the switch is in the process position. When the circuits are broken the switch S2 is in the flush position for cleaning the machine after processing. The mains line is taken to one common connection of switch S1, while the other common connection of S1 is taken tothe coil of waste solenoid valve 20 and the coil of a relay R7. If the selector S1 is switched to energise relay R8, the lefthand side of the circuit diagram would be the programme in the circuit, while if the selector S1 was switched to the opposite direction to energise relay R9, the right-hand side of the circuit diagram would be operated.

Assuming that the switch has been selected to connect relay R8, relays R8 and R10 will energise together. Relay R10 will break the circuit through six microswitches M1 to M5 and M16 for controlling valves X1 to X5 and valve 16, by opening contact RA; by opening contact R10B it will also break the circuit to the pump speed control 109 through which current may be passed, via relay contacts R7A and R1A to the pump 102. At the same time relay R8 will close contacts RSA and R8B, which supply current to contact R10A, and will also have closed contact RSC which derives its current via contact R10B. The current for energising relay R10 flows via timer microswitches TM1, TM3, TMS and process switch S2.

If start button 110 is momentarily pressed, relay R11 is energised and locks itself in the energised condition via its own contacts R11A and R11C. At the same time current is fed via contact R11B to timer clock T1.

Microswitches M1 to M5 and M16 are controlled by cams on the timer clocks T1 to T3. The cams on the clocks may be cut to one half minute, and the first clock arranged to trigger the second clock, and the second clock arranged to trigger the third clock.

When timer clock T1 is energised as previously indicated, a cam carried thereby changes timer microswitch TM1 from the position A to position B, which firstly deenergises relays R10 and R11 and secondly supplies current to the timer T1 directly for four minutes. In the last few seconds of this operation, timer T1 trips microswitch TM2 from position C to position D which starts clock T2. Once clock T2 has started one of its cams trips microswitch TM3 from position E to position F, and at the end of its predetermined time, clock T1 trips switch TM1 back to position A thus maintaining the flow of current to clock T2, and at the same time clock T1 trips switch TM2 back to position C. Similarly when clock T2 is nearly at the end of its cycle, it trips switch TM4 to start clock T3 which in turn moves switch TMS to position K, so that when clock T2 finishes and trips TM3 back to position E, clock T3 receives its current via switches TM3 and TM5.

As indicated above, starting of clock T1 de-energises relay R10 so that current can flow through the microswitches M1 to M5 and M16 and via the waste valve 20 and relay R7. As soon as one of the cams on one of the timers opens one of the microswitches to operate a valve X1 to X5, or valve 16, current is cut off from waste valve 20 and also from relay R7. Thus the contact of relay R7 moves to the position illustrated in FIG. 8, and as soon as the level in probe chamber 19 reaches probe 23, relay R1 operates to close contact RlA and start pump 102.

The microswitches M1 to M5, M16 and TM1 t0 TMS continue to operate until the cycle is completed. At the completion of the cycle, all the microswitches are in the position illustrated in FIG. 8 and relay R10 is again energised, breaking the circuit to the waste valve 20 and to the pump 102. Relays R8 and R10 remain energised until S1 is switched off. In order to flush the apparatus after a process has been completed, switch S2 is broken, which breaks the circuit to relay R10, to allow current to flow through the valve microswitches to the waste valve 20 and relay R7. The circuit is then interrupted by a thirty second timer (not shown) between the microswitch M5 and M16, this timer energising the valve 16 and simultaneously breaking the circuit to the valve 20 and relay R7 This permits water to flow into the apparatus, and allows pump 102 to wash away any solutions left behind at the end of the previous process. Switch S2 is then switched back to the closed position, which again makes the circuit to relay R10.

In use of the above described apparatus to treat a colour print, the print paper is fitted around the inner surface of the walls of the container 33 with its emulsion side innermost, while in a dark room, and the lid 43 is put in place. The print may be held in position by the annular wall 43A and by pins on the inner surface of the cylindrical wall or by means of a vertically extending elongate U-section spring clip, which is engaged between the adjacent edges of the print to tend to expand the print against the container wall. Assuming that one does not wish to effect a colour reversal, the conical reflector 59 is omitted, and the shutter 49 is closed, or a lid having no aperture 48 therein is used. The print in the container 33 is completely sealed from the light, and can be taken out of the dark room and placed on the machine, with the sleeve 40 engaged over the feed pipe 24.

Assuming now that the tank 1 is full of water at the correct temperature, and all of the vessels X are also filled with the correct chemicals, the selector switch is moved to the programme required, the neon 111 lighting up to indicate that this programme has been selected. As described previously, the microswitches are operated in turn so that first of all valve 16 opens and water passes down through tube 101 and flows via distributor pipe 15 to wash completely the walls of chute 14. When the water in chamber 19 has reached probe 23, relay R1 closes contacts RlA and RlB and the water continues to rise and overflows through tube 27. With the relay contact RIA closed, motor 102 starts and pumps the water through feed pipe 24 and up through inner tube 36. The water impinges on the flat lower surface of the lid and runs radially upwardly and cascades down the emulsion face of the print and is collected by a wall 38 to flow through the slot 42 and slots 35A, back down drain tube 25 into chamber 13 where it is recycled by the pump 102. The cam on one of the timers then releases the microswitch M16, 50 that the circuit is made through the solenoid of drain valve 20 which opens, and relay R7 is actuated, so that the pump 102 is switched oil. The timer cams are spaced so as to give sufficient time for all of the water to drain from container 33 and from housing 13. The same operation is repeated, the valve X1 opening instead of valve 16. As before, when the chemical in chamber 19 has reached probe 23, relay R1 closes contacts R1A and RIB and the chemical continues to rise until it touches probe 26, whereupon relay R2 operates this in turn operating relay R3, the contact R3A of which disconnects the solenoid of valve X1. As before the pump starts when the liquid reaches probe 23 and recirculates the chemical. The length of the recirculating period of the pump 102 is determined by the appropriate cam on the timer to give the desired processing time for this chemical. Then, in turn, each of the chemicals ispassed through, with water being circulated between each chemical, when necessary for washing purposes. As indicated previously, the water also passes via connections 30 and 31 to wash out the probe chamber 19. When the cycle of operations has finally been completed, the container 33 may be removed and the print which has been completely treated can be removed from the container 33.

When it is desired to produce a reversal process where a light source is required i.e. when it is desired to make colour prints direct from colour transparencies, the material is fitted within the container 33, in the dark room, to extend around the walls of the container and the conical reflector 59 is slipped into place on the central tube 36. When the lid 43 has been placed on top and the shutter closed, the light housing 54 is mounted on the lid to engage in the annular groove 55 and the shutter opened. A microswitch (not shown) on the controller then turns the lamp 60 on at and for the appropriate time. The graduated conical reflector 59 produces an even distribution of the light over the sensitised material of the transparency.

When it is desired to process roll film, the container of FIG. 7 may be used. The removable assembly within the container 63 is removed and the film inserted into the spiral 67 in the dark room, the assembly fitted back into the container 63 and the lid placed on the top again in the dark room. The container 63 is then fitted onto the feed pipe 24 as previously discussed and the machine operated in the manner indicated earlier. When this form of container is used, water or chemical flows up through the tube 61 impinges on the lid 62 and runs down the sides of the container 63. The level of the water within the container steadily rises and the film is thus treated on both faces. Air which is displaced, during rising of the liquid, is forced out through slots 65 and when the level of liquid reaches the top of the annular weir 68, it will be syphoned out down the inside of the Weir and will be fed back to the processing housing 13 for recycling. Thus the level of liquid will not rise above the top of the spiral.

If it is desired to treat sheet or cut film, the container of FIG. is used, this in many ways being similar to the container of FIG. 7. The container of FIG. 10 has an outer wall 75 and includes a sypho-ning arrangement which is identical to that of FIG. 7, the feed tube, slots and syphon housing being indicated by reference numerals 61A, 65A and 64A respectively. Also mounted within the container 75 is a block 76, which simply reduces the volume of the container 75 and a pair of mounting guides 77, only one of which is shown, the other being a mirror image. The mounting guides include facing vertical slots 78 and a smaller number of horizontal slots 79. The sheet film is slid down into the slots 78, the guides being so spaced that the sheets are slightly bowed so that they may be evenly spaced without touching one another.

If it is desired to process a number of roll films, each film may be wound onto a hanger as illustrated in FIG. 11. The hanger includes an essentially solid body 80 with outwardly extending support bars 81 and channels in its outer surface. The film 82 is held in position on the body 80 by spring clips 83. The hanger is supported in tank 75 by engagement of the support rods 81 in grooves 79. By this means a number of films may be supported within the container and treated at one time.

It is proposed to provide facilities for constantly maintaining the vessels X full of their respective chemicals. This may be achieved by supplying, for example, under the processing deck, ten sockets to receive bottles of the chemical solution, and a pump for each socket controlled by a level indicator in the associated vessel X.

The amount of each solution admitted during each of the processing cycles is dependent upon the size of the container placed on the apparatus and sleeve tubes may be provided to reduce the diameter of the feed pipe 24 in the processing housing to reduce the chemical in circuit for the smaller containers. Similarly the shape and size of the chute 14 may be varied to suit the number of valves and processes required, and the valves X1 to X10 and 16 may be staggered in a V-formation to permit an equal amount of each solution entering the housing 13 to compensate for the width of the chute 14.

It will be appreciated that the invention provides a relatively inexpensive apparatus, which is capable of carrying out short runs using only small quantities of chemical and which is thus capable ofprinting at a much more economical rate than has hitherto been possible. An even and continuous agitation of the solutions is provided during the cycle by the solution flowing over the surface of the print and by the pumping action. Moreover, by the accurate control of the temperature of the chemicals, and the time of circulation of the chemicals through the processing container, an extremely accurate processing can be provided with results which have perfectly consistent colour balance. Furthermore large prints and murals can be produced in an apparatus which is relatively small.

I claim:

1. Apparatus for processing photographic sheet or film material, said apparatus comprising, in combination:

(a) a processing chamber;

(b) a light proof container releasably mountable on said processing chamber elfective to receive the material to be processed;

(c) an upper interior surface to said container;

(d) a pump communicating with said processing chamber and having a pump outlet;

(e) a feed pipe connected to said pump outlet and extending substantially vertically upwardly into said container;

(f) an open upper end to said feed pipe located a short distance below said upper interior surface to said container;

(g) drain means to said light proof container effective to return liquid from said container to said processing chamber for recirculation; and

(h) means for selectively feeding chemicals and rinsing water at a desired temperature to said processing chamber.

2. Apparatus as claimed in claim 1, wherein said processing chamber includes an open-topped drain tube communicating with the chamber interior, and an opentopped feed tube mounted within said drain tube and connected to said pump outlet.

3. Apparatus as claimed in claim 2, wherein said light proof container includes a depending tube effective to engage said drain tube, wherein said depending tube communicates with the interior of the container via a light trap, and wherein the feed pipe is carried by said depending tube, effective to engage said open-topped feed tube.

4. Apparatus as claimed in claim 3, wherein said container includes a removable lid and a transverse wall near the lower end thereof, wherein said depending tube is formed with slots immediately above said transverse wall and wherein said light trap includes a plurality of slotted plates in said dependening tube at a location below said transverse wall.

5. Apparatus as claimed in claim 4, and further comprising a housing containing a light source mountable on said lid, wherein said lid is provided with an openable-shutter, and wherein a conical reflector is mountable around said feed pipe.

6. Apparatus as claimed in claim 3, wherein said container has mounted therewithin a closed-topped, openbottomed syphon tube, surrounding and extending above said depending tube in spaced apart relation thereto, and wherein means is provided for mounting photographic sheet or film material exteriorly of said syphon tube.

7. Apparatus as claimed in claim 1, wherein said means for selectively feeding chemicals and rinsing water at a desired temperature, include a tank, a plurality of vessels for chemicals arranged in said tank, means for feeding water to said tank, outlet valve means associated with said tank for feeding water therefrom to said processing chamber, further outlet valve means for feeding chemicals from each of said vessels to said processing chamber, means for maintaining the temperature of the water in the tank substantially at the desired value and control means for selectively operating said valve means.

8. Apparatus as claimed in claim 7, wherein said means for filling the tank include a hot water conduit, a cold water conduit, valves controlling the flow of the water through said hot and cold water conduits, depth probes in said tank operatively associated with said valves, and a temperature sensitive device operatively associated with said valves effective to control the flow of hot or cold water into said tank to maintain the level and temperature of the water substantially at the desired value.

9. Apparatus as claimed in claim 8, and further comprising electrical heater means and a stirrer in said tank.

10. Apparatus as claimed in claim 7, wherein the control means include cam actuated microswitches and wherein the outlet valves are solenoid operated, said microswitches being effective to open and close said outlet valves.

11. Apparatus as claimed in claim 10, wherein the processing chamber includes depth probes effective to close said further outlet valves when the level of chemical in said processing chamber reaches a desired value.

12. Apparatus as claimed in claim 11, wherein said outlet valve means associated with said tank is connected to said processing chamber firstly via a distributor pipe and a chute and secondly via a spray device positioned to spray water over said depth probes in said processing chamber.

13. Apparatus as claimed in claim 12, wherein further outlet valve means are positioned to feed chemicals to said processing chamber via said chute.

References Cited NORTON ANSHER, Primary Examiner F. L. BRAUN, Assistant Examiner US. Cl. X.R.

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