Photographic Developing Apparatus

Abstract

Developing apparatus for the rapid development of photographic silver halide elements, e.g., sheets or plates, having a series of spaced solution-applying plates having (1) a plurality of spaced slots of small cross-section for supplying photographic treating solutions to the surface of the applying plates and to a single surface of the photographic elements passed across the applying plates, and (2) a collection and storage tray for receiving excess solution flowing over the edges of the plates. Between the applying plates are pressure or squeegee rolls for removing expended solutions, drip pans for the solutions, cover plates extending over the applying plates and flexible sealing strips at the entrance and exit lips of the cover plates, which strips are adapted to press against the back surface of the photographic elements. Metering weirs control the rate at which treating solution is expended. The apparatus can have a self-threading drying chamber adjacent the final solution applying plate.

Parent Case Text

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. Patent application Ser. No. 79,214 riled on Oct. 8, 1970, now abandoned, and is a continuation-in-part of Assignee's copending application R. H. Beck, Ser. No. 886,618, Dec. 19, 1969, now Pat. No. 3,635,144.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to apparatus for continuous processing of exposed photographic films.

2. Description of the Prior Art

There are many types of photographic developing and fixing apparatus for continuous processing of exposed photographic films and papers. They differ widely in construction. Many have developing, fixing, and washing tanks.

Pask, U.S. Pat. No. 2,419,853, Apr. 29, 1947, discloses such an apparatus for applying developing solution to a moving film, the solution-applying plate has a plurality of perforations for applying processing solution to the film.

The fixed blocks over the film prevent observation and ready access to the film during development and there are no sealing strips and no slits in the solution applying plate as in the apparatus of the present application.

Wright, U.S. Pat. No. 3,027,821, Apr. 3, 1962, discloses a developing apparatus having a developer applying plate with a narrow central slit for feeding solution to the surface of the plate.

Joggling means is required to maintain a smooth flow to the plates and there are no sealing strips as in the photographic apparatus of the present application.

Wright, U.S. Pat. No. 3,192,846, July 6, 1965, discloses sucy an apparatus having inlet slots in the solution applying plate. There are no sealing strips and there is no reservoir for maintaining a smooth flow of solution to the plates.

SUMMARY OF THE INVENTION

The photographic treating apparatus of this invention comprises a series of spaced, separate, treating solution-applying units and means positioned between the solution-applying units for transporting a photographic element along a path extending through the units and for removing excess treating solution from such photographic elements, each solution- applying unit having:

1. solution-applying means positioned below said path for applying treating solution to only the surface of such photographic element adjacent said solution-applying means, said solution-applying means consisting solely of a single horizontal solution-applying plate, with a plurality of spaced slots of small cross sections, positioned below said path;

2. means for supplying treating solution to the upper surface of said plate with a force sufficient to support the photographic element over said plate and to allow the treating solution to be applied to only the surface of such photographic element adjacent said plate; and

3. a sealed collection and storage container containing said plate and comprising a tray disposed beneath said plate for receiving excess treating solution flowing over the edges of said plate, and a cover disposed above said plate, said container having entrance and exit orifices located at the level of said plate and in said path for receiving such photographic film, and flexible sealing strips attached to said container at the entrance and exit orifices to prevent oxidation of the treating solution and to facilitate self-threading of the photographic element through the apparatus.

The sealing strip of the exit end of the tray may coact with a weir on the lip of the tray.

There may also be provided: tanks for the treating solution; means for recirculating the treating solution from the storage tray to the supplying slots; solution-controlling means, comprising metering weirs coacting with exit sealing strips to control the rate of removal of expanded solution, solution level sensors (not shown) in the collection and storage tray; and gravity or pump means for adding new solution. The solution received in the drip pans can, if desired, be recirculated to the solution-applying plates. The transport and solution-removing means may be pressure rollers disposed between each solution-applying unit through which the photographic element passes. Beneath the rollers are drip pans for receiving excess solution. As any treated elements pass from the final treating solution and pressure rollers, they can pass into a self-threading dryer through which heated air flows or is applied by means of air jets.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an elevation with parts in section of the photographic treating apparatus.

FIG. 2 is a elevation of a pair of solution-applying plates showing collection and storage trays, solution tanks, pump, drip trays, and a recovery tank.

FIG. 3 is a plan view of the upper section of a solution-applying plate with the reservoir supplying inlet in dashed outline.

FIG. 4 is an elevation of a portion of the cover plate and solution-applying plates and associated members.

FIG. 5 is a section taken along line 5--5 of FIG. 4.

FIG. 6 is a plan view of an air flotation dryer plate.

FIG. 7 is an end elevation of the drying chamber with parts in section of the plenum chambers.

FIG. 8 is a schematic view of a suitable electrical circuit for the apparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to the drawings, wherein the same reference numerals are used throughout the several figures, the apparatus has a horizontal frame 1 with end rails 2, side rails 3, crossbars 4 and a suitable angle iron or lengthwise bracket 5 and legs 6.

Disposed in collection and storage trays, which are supported, e.g., by the angle irons near their side edges, are solution-applying plates 7. These plates have an upper section 8 and a lower section 9. The upper section has a plurality of spaced inclined slots 10 of small cross-section. The lower section of the plate 7 has formed in its upper surface a reservoir 11 with an inlet 15 which can be centrally disposed.

The apparatus is provided with collection and storage trays 30 which have a suitable outlet to which is attached outlet pipe 31. Solution passes from the outlet through pump 32 and pipe 33 which is connected to inlet 15 in plate section 9.

A cover 21 (preferably transparent) for the solution-applying unit has a slightly raised central portion, the side edges 22 being flat (not shown) and resting on the surface edges of collection and storage tray 30. The cover has a deflecting entrance lip to direct passage of photographic film over the surface of plate section 8. The rear portion of the cover has a similar deflecting exit lip. Attached to the deflecting front and exit lips, respectively, are flexible sealing strips 25 and 25'. These sealing strips extend across the entire width of the cover and seal the entrance and exit from the trays 30 to prevent deterioration of the treating solution. The bottom parts of the sealing strips are free and in contact with the back surface of any photographic element W passing through the apparatus.

Metering weirs 12 are formed by ridged plate 13 disposed on and fastened to the exit lip of the tray 30. The metering wier 12 area is determined by the geometry of the ridges 14. The weir area is calculated to allow the expenditure of a predetermined, amount of solution adhering to the surface of the treated photographic element. Solution is expended at a controlled rate directly proportional to the surface area of treated photographic element.

A solution supply tank 37 is in communication with the collection and storage tray via tube 34 and pump 35. A solution level sensor (not shown) in the collection and storage tray controls pump 35. When the solution level falls below a predetermined level in the collection and storage tray, the solution level sensor starts pump 35 and new solution is supplied to the tray 30 via tube 34.

Between adjacent solution-applying plates are drip trays 39 to which there are attached drain tubes 40 which transport solution to a drain or receptacle 32.

At the end of the solution-applying section of the apparatus, there can be disposed a drier 41 having an upper plenum chamber 42 provided with exit duct 43. Lower plenum chamber 44 is below the upper chamber and an air inlet duct 45 is disposed below chamber 44. Upper and lower plenum chambers house air flotation dryer plates 46 and 46' in an opposed relationship. Plates 46 and 46' have a plurality of small orifices 47 spaced over their surfaces. A positive pressure drop of one-half inch of water or greater across the orifices floats the photographic element through the drying chamber. The air flotation drying chamber allows self-threading of a continuous photographic element or automatic drying of discrete sheets of photographic element.

Near the entrance end of the first solution --(e.g., developer solution) applying unit are transport rollers 50 and 50' which contact the photographic film and propel it forward. These transport rollers have shafts 52 on which are fixed suitable sprocket 53 which are driven by chain 54 passing around said sprockets and around idler sprockets 55 and 56 near the respective ends of the apparatus. The chain also meshes with driving sprockets 57 on reducing gear 58 of drive motor 59. The chain also meshes with and drives suitable sprockets which are attached to biased pressure or squeegee rollers 60 and 61 at the end of each solution-applying plate.

With reference to the wiring diagram of FIG. 6, the processing apparatus of this invention can be provided with six motors (M).

Motor M1 activates a pump for circulating developer solution, as shown in FIG. 2.

Motor M2 activates a pump like 32 for circulating a treating solution.

Motor M3 corresponds to driving motor 59 of FIG. 1.

Motor M4 (not shown in FIG. 1) drives a blower for supplying hot air through entrance duct 45.

Motor M5 drives a suitable ventilating fan (not shown) for passing air over the processing machine.

Motor M6 activates a pump for supplying new developer solution.

Motor M7 activates a pump for supplying new treating solution.

Each of the motors are activated by closing the main switch shown in the wiring diagram, except M6. The main switch also controls the current for three heaters, one of which heats air that is introduced into dryer 41.

Motor M6 is controlled by the solution level sensor.

Additional heaters (not shown) for raising the temperature of the developing solution and the bleaching solution, respectively, are activated by current controlled by the main switch. By inserting suitable thermostats in the developer and bleaching solution, their respective temperatures can be controlled.

The operation of the apparatus is obvious from the drawings and the above description. When the main switch of the floating film processing apparatus of this invention is closed, the developer-circulating and treating solution circulating pumps begin to circulate the solutions through the respective solution-applying plates. Simultaneously, air is supplied by means of a blower to the dryer. Power is simultaneously supplied to the heaters for the processing solutions.

The drive motor 59 starts the transport rolls and idler sprockets to turn in synchronism. The ventilating fan is activated by its motor and removes heat from the motors and the dryer.

After startup, when the solutions and dryer are at a suitable temperature, the photographic film or paper W can be introduced into the machine. If desired, electrical interlocks can be provided so as to delay operation of the transport motor unitl the temperatures are at the desired degree.

Various parts of the apparatus can be made of stainless steel or other non-corrosive metal alloy, or made of suitable resins or polymers, e.g., phenol formaldehyde resins, polyethylene, etc., that are resistant to heat and chemicals.

In particular, the upper and lower sections 8 and 9 of the solution-applying plates can be vacuum molded from acrylic resin or other plastic material or sheets, and reinforced, if necessary, to provide the desired rigidity. They can be fastened at their interface with a plastic cement or by screws or other suitable fasteners.

The apparatus of this invention has the advantage that it is simple and dependable.

Claims

What is claimed is:

1. An apparatus for treating a photographic element which comprises a series of spaced, separate, treating solution-applying units and means positioned between the solution-applying units for transporting a photographic element along a path extending through the units and for removing excess treating solution from such photographic elements, each solution applying unit having:

a. solution-applying means positioned below said path for applying treating solution to only the surface of such photographic element adjacent said solution-applying means, said solution-applying means consisting solely of a single horizontal solution-applying plate, with a plurality of spaced slots of small cross sections, positioned below said path;

b. means for supplying treating solution to the upper surface of said plate with a force sufficient to support the photographic element over said plate and to allow the treating solution to be applied to only the surface of such photographic element adjacent said plate; and

c. a sealed collection and storage container containing said plate and comprising a tray disposed beneath said plate for receiving excess treating solution flowing over the edges of said plate, and a cover disposed above said plate, said container having entrance and exity orifices located at the level of said plate and in said path for receiving such photographic film, and flexible sealing strips attached to said container at the entrance and exit orifices to prevent oxidation of the treating solution and to facilitate self-threading of the photographic element through the apparatus.

2. An apparatus according to claim 1, wherein the sealing strip at the exit orifice coacts with a weir on the lip of the tray.

3. An apparatus according to claim 1, wherein the cover is transparent.

4. An apparatus according to claim 1 having a tank for treating solution.

5. An apparatus according to claim 1, wherein the slots pass through the plate at less than a 90.degree. angle.

6. An apparatus according to claim 1 which is provided with means for recirculating solution in the tray to the solution applying plate.

7. An apparatus according to claim 1 wherein said transport and solution-applying means comprise a plurality of pressure rollers between the solution-applying units through which the element passes.

8. An apparatus according to claim 7 further comprising a drip pan disposed beneath the pressure rollers to receive excess solution.

9. An apparatus according to claim 1 having a drying chamber adjacent the final solution-applying unit.

10. An apparatus according to claim 9 wherein said drying chamber has flotation drier plates with a plurality of small orifices for drying air, such photographic elements being adapted to pass between the plates while being supported by the drying air.