US 3610131 A
Description (OCR text may contain errors)
7 HANS-DIETER FRICK 3,610,131
.MAGHINE FOR LIQUID TREATMENT OF PHOTOGRAPHIG FILMS 0R 'I'HH [JIKIJ 3 Shoots-Shoot 1 Filed June 17, 1968 INVENTOR.
Oct. 5, 1971 HANS'DIETER FRICK L MACHINE FOR LIQUID TREATMENT OF PIIOTOGRAPHIC FILMS OR THE L'IKIC Filed June 17, 1968 77 37A 34' 2 41 35A 40 37c 31' 376331; 24"
3 Shocts-Jheot 2 cINVENTOR. HANS-DIETER FRI K PETERD HUBER DAWI OWITSCH lNAND-LEONHARD SCHOUTEDEN A KOCOUREK RD POSCH WOLFGANG VlEHRlNG BY "mil [0! 31'6"!!- til/or 1971 HANS-DIETER FRICK ETA!- 3,610,131
MACHINE FOR LIQUID TREATMENT OF PHOTOGRAPHEO FILMS OR THE LIKE Filed June 1.7, 1968 3 Sheets-Sheet 5 Fig.5
ER DAWID NAND-LEONHARD SCHOUTEDEN United States Patent ofi s 3,610,131 Patented Oct. 5, 1971 Int. Cl. G03d 3/12 US. CI. 9594 8 Claims ABSTRACT OF THE DISCLOSURE A developing machine for exposed photographic films has a series of tanks each of which accommodates a chamber consisting of upper and lower containers de fining between themselves a channel wherein the films advance during travel through the respective tank. The containers have orifices which discharge liquid into the re spective channels in such a way that the liquid flows counter to the direction of film travel and forms streams at both sides of films. The orifices are circular holes or elongated slits and their cross-sectional area may be fixed or adjustable. The orifices are adjacent to the film discharging ends of the respective channels.
BACKGROUND OF THE INVENTION The present invention relates to machines for treating sheet-like workpieces with liquids, and more particularly to improvements in developing machines for exposed photographic film or the like. Still more particularly, the invention relates to improvements in machines wherein travelling sheets of film or like sheet material are treated by contact with liquid streams.
In presently known developing machines, sheets or rolls of films are transported lengthwise and the liquid is caused to flow along both sides of the film but at a higher speed. In this way, the liquid streams facilitate the entry of the leading end of the film into and its advance through the machine. A drawback of such machines is that, in order to complete the treatment within a reasonably short period of time, the speed of the liquid streams must be much higher than the speed of film. This can be achieved by subjecting the liquids to substantial pressure by resorting to large pumps or analogous liquid displacing devices. More over, the pumps must circulate large quantities of liquids which is undesirable because the machine is bulky and particularly because the developer is sensitive to oxidation. Any reduction in the speed of liquid streams necessarily entails a reduction in the speed of film travel because the rate at which the film is developed depends on the diiference in the speeds of liquid and film.
SUMMARY OF THE INVENTION It is an object of our invention to provide a machine which can be utilized for developing of exposed photographic films and wherein the circulation of liquids which are brought into contact with films can be eifected with simpler apparatus and with savings in energy.
Another object of the invention is to provide a machine of the just outlined character which can complete the treatment of travelling films within shorter periods of time than presently known machines.
A further object of the invention is to provide a machine which can subject travelling films or like sheet-like workpieces to a series of successive treatments and wherein both sides of each workpiece are treated with the same intensity.
An additional object of the invention is to provide a machine wherein the liquids which treat the workpieces contribute to proper guidance of workpieces during travel toward and past one or more treating stations.
An ancillary object of the invention is to provide a machine which can treat photographic films in rapid sequence, wherein the intensity of treatment can be regulated with a desired degree of precision, and wherein the liquids which are likely to oxidize are protected from excessive contact with air in a novel and improved way.
Still another object of the instant invention is to provide the above outlined machine with novel means for regulating the rate of fiow of liquids which come into contact with workpieces and to further provide the machine with novel means for recirculating such liquids into renewed contact with workpieces.
A further object of the invention is to provide a machine which can be adjusted to accommodate and treat workpieces of different thickness, length and/ or width and which requires a minimum of supervision.
Briefly outlined, the invention is embodied in a machine which can be utilized for treatment of sheet-like workpieces, particularly for developing, fixing and washing of exposed photographic films. The machine comprises transporting means for advancing workpieces in a predetermined direction along a predetermined path which is preferably located in a substantially horizontal plane, a treating chamber defining an elongated channel through which the workpieces advance during travel along the path and comprising portions flanking the channel from above and below and each having at least one orifice which directs a stream of liquid into the channel so that the liquid flows along the respective side of the workpiece in the channel and counter to the direction of travel of workpieces, and means for supplying liquid to the chamber.
The chamber is preferably mounted in a tank which collects liquid that issues from the channel so that the thus collected liquid can be withdrawn by the aforementioned supplying means for recirculation through the chamber. The tank may be sealed against entry of air, particularly if the liquid tends to oxidize on contact with air, or the supply of liquid in the tank can be shielded from air by a floating lid.
Each portion of the chamber may be provided with one or more elongated slit-shaped orifices or with one or more rows of circular or short slit-shaped orifices. If each portion of the chamber comprises a single orifice or a single row of orifices, such orifices are preferably provided close to the discharge end of the channel so that liquid issuing from such orifices can treat the workpieces during flow through the major part of the channel prior to issuing at the intake end of the channel to be collected in the bottom zone of the tank.
The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved machine itself, however, both as to its construction and its mode of operation, together with additional features and advantages thereof, will be best understood upon perusal of the following detailed description of certain specific embodiments with reference to the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal vertical sectional view of a developing machine which embodies one form of the invention;
FIG. 2 is an enlarged fragmentary perspective view of a container forming part of a treating chamber in the machine of FIG. 1;
3 'FIG. 3 is a fragmentary longitudinal vertical sectional view of a second developing machine;
FIG. 4 is a plan view of a container in the machine of FIG. 3, with certain of its parts omitted; and
FIG. is a vertical sectional view as seen in the direction of arrows from the line VV of FIG. 4.
DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 illustrates a portion of a developing machine which comprises a vessel 1 whose width exceeds somewhat the maximum width of film 2 to be processed in the machine. The distance between the axes of succes- I sive pairs of transporting rolls 3, 4 is somewhat less than the length of shortest films which are to be treated during travel through the vessel. The speed at which the film is transported depends on the time required for treatment in successive portions of the vessel 1. This vessel is provided with two transversely extending vertical partitions 1a, 1b which extend from the bottom wall of the vessel and close to the path for the film 2. It can be said that the vessel 1 is composed of three tanks 1A, 1B, 1G in the first of which the film is treated by a liquid developer, in the second of which the film undergoes treatment by contact with a fixing bath, and in the third of which the film is treated with water. The bottom portions of tanks 1A-1C are respectively provided with outlets 1c, 1d, 1e.
The vessel 1 preferably consists of synthetic plastic material and each of its tanks accommodates two pairs of transporting rolls 3, 4. These pairs of rolls are adjacent to the intake and discharge ends of the respective tanks. The means for driving the rolls 3 and 4 comprises a gear train including two meshing gears for each pair of rolls 3, 4 and a feed screw or worm shaft 3A which is driven by a motor (not shown) and extends along one side wall of the vessel. The shaft 3A transmits torque to all of the gears. It is desirable to bias the rolls 3, 4 of each pair against each other, for example, by mounting the shaft or bearing of at least one roll for movement toward and away from the shaft or hearing of the other roll and by placing a prestressed endless helical spring around such shafts or bearings.
A platform or table 5 is mounted at the outer side of the vessel 1 adjacent to and below the inlet of the first tank 1A to serve as a support for exposed film 2 and to guide the film into the nip between the first transporting rolls 3, 4. The leading edge of film 2 can be pushed toward the adjoining rolls 3, 4 and the film is thereupon automatically transported through the tanks 1A1C and is discharged from the vessel 1. The last tank 1C is adjacent to a drier 6 which defines a horizontal path for treated film and accommodates several pairs of transporting rolls 7, 8 as well as nozzles 3 which blow air against both sides of the film. A similar drier is disclosed in the copending application Ser. No. 566,691 filed July 20, 1966 by Keller et al. and, now Pat. No. 3,438,140, assigned to the same assignee.
The tanks 1A, 1B, 1C respectively accommodate novel treating chambers 10, 11 and 12 each of which comprises two mirror symmetrical portions or containers one of which is shown in greater detail in FIG. 2. This illustration shows the lower container a of the first treating chamber 10. The container 10a is connected with a supply conduit 10b which feeds thereto liquid developer from a pump 100. The pump 10c draws liquid developer from the outlet 10 of the tank 1A. Thus, the liquid circulates in a closed path from the pressure side of the pump 100, into the container 10a by way of the supply conduit 10b, into the tank 1A, and to the suction side of the pump by way of the outlet 1c. The pump 10c can also supply liquid developer to the upper container 10a of the chamber 10 or the container 10a may receive liquid developer from a separate pump which also draws liquid from the tank 1A. It is clear that the machine may be equipped with a regenerating unit (shown at 10d in FIG.
4 1) which admits to the liquid chemicals at a rate proportional to the rate at which the exposed film is transported through the tank 1A. The top of the vessel 1 is preferably closed by a cover 13 provided with openings or cutouts for supply conduits and other parts which extend from the interior of the vessel.
The container 10a has an undulate top portion or panel 15 whose undulations extend transversely of the direction of film travel and are mirror symmetrical to those formed by the top panel 15' of the upper container 10a. The panels 15, 15a define between themselves an elongated channel lSA whose height varies gradually between a maximum height (between two valleys) and a minimum height (between two hills). In the illustrated embodiment, each of the panels 15, 15' is formed with three valleys and the panels together define four constrictions in the channel 15A including two outermost constrictions and two intermediate constrictions.
The panel 15 has two lines or rows of orifices 17 whose axes are normal or nearly normal to the surrounding portions of the panel and which discharge streams of liquid developer into the channel 15A. The orifices 17' of the panel 15' are mirror symmetrical to the orifices 17 with reference to the plane of the film 2. The orifices 17, 17' are provided upstream of the second and fourth constrictions in the channel 15A, i.e., in such portions of the panels 15, 15' which slope toward the plane of the film 2. It will be seen that the orifices 1'7, 17' discharge liquid developer in a direction which has a component in a horizontal plane and is counter to the direction of film advance. The deforming action of streams which issue from the orifices 17 and impinge against the underside of the film 2 is compensated for by the deforming action of streams which issue from the orifices 17'.
The front, rear and bottom panels of the container 10a shown in FIG. 2 are formed by a one-piece U-shaped body 14 of synthetic plastic material whose edges are welded to the top panel 15 and to two fiat lateral panels 16 (only one shown in FIG. 2). The top edges of the panels 16 extend beyond the crests of the panel 15 by a distance which is about of an inch so that, when the lateral panels of the upper container 10a are placed against the lateral panels 16 of the container 10a, they form two continuous barriers along the sides of the channel 15A and insure that the constrictions of the channel 15A are wide enough (about of an inch) to permit passage of thicker or thinner films and of layers of developing liquid along both sides of the film (but in the opposite direction). As stated above, the rows of orifices 17, 17' are located upstream of the adjoining constrictions in the channel 15A. The U- shaped part 14 of the lower container 10a rests on projections (not shown) which extend inwardly from the side walls of the tank 1A. The upper container 10a rests on the lateral panels 16 of the container 10a.
In the machine of FIGS. 1 and 2, the orifices 17, 17' are of circular outline and have a diameter of about ,5 of an inch. The distance between the orifices of a row is about of an inch, i.e., about ten times the diameter of an orifice. However, it is equally within the purview of the invention to provide the panel 15 and/or 15' with orifices in the form of slits which extend transversely of the direction of film travel, to provide such panels with circular and slitshaped orifices, and/or to stagger the orifices of each row in the direction of film travel.
The liquid developer which issues from the orifices -17, 17' flows in the channel 15A toward the platform 5 and is intercepted by a trough 18 located below the first pair of transporting rolls 3, 4. The trough 18 has a pipe 19 which discharges the liquid into the bottom zone of the tank 1A. The aforementioned supply conduit 10b for the lower container 10a preferably extends along one of the lateral panels 16 and through an opening or cutout in the cover 13.
Good results were achieved with containers having a width of about 16 inches, rows of orifices with a diameter of about of an inch, and with liquid developer which was maintained at a pressure of about one-half atmosphere above atmospheric pressure. The films were developed rapidly and with very satisfactory uniformity.
The undulations of panels 15, 15' contribute to rigidity of the containers a, 10a which is important to insure that the containers undergo negligible deformation when they accommodate pressurized liquid. In other words, the width of constrictions in the channel A changes very little or not at all, even in the regions substantially midway between the lateral panels 16. Furthermore, each chamber can be readily cleaned because the containers 10a, 1011' are separable from each other so that the orifices 17, 17 are accessible for periodic inspection and/ or cleaning. Simplicity, ruggedness, low cost, reliability and compactness are but a few of several advantageous features of the improved developing machine.
The intercepting trough 18 serves the purpose of reducing contact between liquid developer and surrounding air. It is well known that the developer is sensitive to oxidation and, in the absence of the trough 18 and its pipe 19, liquid issuing from the upstream end or intake end of the channel 15A would be in long-lasting contact with air prior to entering the bottom zone of the tank 1A. Such large-area contact between air and liquid developer would cause excessive oxidation. The trough 18 resembles a hopper or funnel and its cross-sectional area diminishes toward the upper end of the pipe 19. This trough intercepts liquid which flows countercurrent along both sides of the film, i.e., also such liquid which is discharged by the upper orifices 17'. On entering the trough 18, the liquid forms a rather thick stream so that the area of contact with air is reduced to a minimum. It is preferred to provide a readily separable connection between the trough 18 and the container 10:: and/ or 10a or between the trough and the tank 1A. The top panel 15 of the lower container 10:: preferably extends rearwardly beyond the U-shaped body 14 and is located directly above the open upper end of the trough 18. The contact between air and liquid developer can be reduced still further if the tank 1A accommodates a floating lid or swimmer which rests on top of the body of liquid in the bottom zone of the tank. The dimensions of the swimmer 20 preferably approximate the dimensions of the space in the tank 1A below the lower container 100. This swimmer has an aperture which accommodates the pipe 19 with sufficient clearance to permit upward and downward movements of the swimmer, depending on the level of liquid in the tank 1A.
Another mode of preventing premature oxidation of developer is to form the tank 1A as an airtightly sealed plenum chamber and to fill the space above the liquid developer with nitrogen or other protective gas. This modification is indicated diagrammatically in FIG. 1 which shows a pipe 20A connected to the tank 1A and to a source 20B of protective gas. It was found that the gas prevents penetration of oxygen into the tank 1A even if the pressure of such gas exceeds very slightly the pressure of the surrounding atmosphere. In order to maintain such slight overpressure, the pipe 20A contains an adjustable valve 20C which admits small quantities of gas from the source 20B. The valve 20C is preferably a solenoid-operated valve which may be connected in series with the motor for the pump 100 so that it opens in automatic response to admission of liquid developer into the container 10a.
In accordance with a further modification of the present invention, the film 2 can be conveyed or transported along a substantially U-shaped path by means of transporting elements which are immersed in the liquid developer. The intensity of developing action is then reduced but is compensated for by longer-lasting contact between the film and liquid developer because the film travels along a U- shaped path.
The manner in which the film is treated by a fixer in the tank 1B and by water in the tank 10 is the same as described in connection with the tank 1A and its chamber 10.
An important advantage of our machine is that the relative speed between the liquid streams and the films 2 is very high even though the liquid streams need not be conveyed at a high speed. This is due to the fact that the liquid flows counter to the direction of film travel. Since the relative speed between the films and liquid is high even if the speed of the liquid streams is low, the machine can operate properly with pumps whose output is low. Furthermore, the upper and lower containers of the treating chambers 10, 11 and 12 can define relatively short channels because the films are subjected to intensive treatment by liquid streams which fiow counter to the direction of film travel. If the channels are relatively long, the rate of film transport can be increased well beyond the rate which is permissible in presently known machines wherein the liquid flows in the direction of film travel.
Another advantage of our machine is that the width of channels between the containers of the treating chambers 10, 11, 12 varies continuously. This is particularly important in the first tank 1A because the undulate surfaces of panels 15, 15 insure repeated and very intensive mixing of ingredients in the liquid developer. Furthermore, and as mentioned above, the paels 15, 15' insure very satisfactory guidance of workpieces through the respective channels. The streams issuing from the first two rows of orifices 17, 17 center the leading edge of the film 2 in the channel 15A as soon as the film enters by way of the intake end of the channel and is thereupon conveyed midway between the panels 15, 15 so that each of its sides is treated with the same degree of intensity.
FIGS. 3 to 5 illustrate a portion of a second developing machine. The tank for liquid developer is shown at 101A; this tank accommodates a chamber which comprises two portions or containers 31, 31'. The means for transporting the film 21 lengthwise through the channel A between the containers 31, 31' comprises two pairs of transporting rolls 22, 23 and 24, 25. The lower rolls 23, 26 are fixed to gears (not shown) which mesh with gears 27, 28, and the gears 27, 28 are respectively rigid with sprocket wheels 27A, 28A driven by an endless chain 30 whose upper stretch travels along a horizontal rail or a like support 29. The chain 30 is driven by a suitable motor which is not shown in the drawing. The upper transporting rolls 22, 24 are driven by gears (not shown) which mesh with the companion gears of the lower rolls 23, 25 or rotate merely in response to frictional engagement with the lower rolls and/or film 21. The drive for the transporting rolls is preferably installed externally of the tank 101A. The chain 30 can be employed to drive only the transporting rolls of the tank 101A or to drive the transporting rolls of the adjoining tank or tanks corresponding to the tanks 1B, IQ of FIG. 1.
The containers 31, 31 are mounted in the space 26 between the two pairs of transporting rolls. The container 31 is mirror symmetrical to and is practically identical with the container 31'. The following part of this description will refer mainly to the lower container 31 with the understanding, however, that the upper container 31' is of identical or substantially identical design; its parts are denoted by similar numerals each followed by a prime.
The container 31 comprises a trough-shaped main body portion 31A which preferably consists of synthetic plastic material and is provided with a transversely extending internal partition 31a located between the front and rear panels 31f, 31d but closer to the front panel 31 In accordance with a presently preferred embodiment of the invention, the distance between the partition 31a and the front panel 317 is substantially half the distance between the partition 31a and rear panel 31a. The partition divides the interior of the container 31 into a compartment or duct 31b for liquid developer and an unused compartment 310 which is sealed against entry of developer. The compartment 310 is sealed from above by a top panel 32. It was found that the amounts of liquid developer which can be furnished by the compart ments or ducts 31b, 31b are amply sufficient to insure rapid treatment of film 21 which advances through the channel 115A.
The bottom portion of the duct 31b is bounded by a V-shaped surface 31c which defines a transversely extending groove. An insert 33of thin sheet metal has a portion which overlies the surface 31c and whose marginal portions are bent to form two transversely extending flaps. The material of the insert 33 is elastic and rustproof (for example, metallic sheet stock known as V4A). Combined deforming or anchoring means including one or more screws 34 is provided to secure the insert 33 to the main body portion 31A and to deform that portion of the insert which overlies the surface 31e. The screws 34 can be reached at the outer side of the container 31 to facilitate adjustment and hence the extent of deformation of the insert 33. When the screws 34 are tightened, that portion of the insert 33 which is adjacent to the front panel 31] pivots along the edge 33b and moves away from the front wall.
A second insert 35 of thin sheet metal is screwed or otherwise affixed to the top panel 32 at a level above the partition 31a. The unattached portion of the insert 35 extends forwardly, first in substantial parallelism with and thereupon toward the path for the film 21. The inserts 35, 35 define a constriction of the channel 115A and thereupon flare outwardly (away from the film path) to define with the adjoining flaps 33a, 33a of the inserts 33, 33' two transversely extending slit-shaped orifices 117, 117' which discharge liquid developer from the ducts 31b, 3112 into the channel 115A in such a way that the developer flows counter to the direction of film travel and along both sides of the film 21. The foremost end portions of the inserts 35, 35' make with the plane of film 21 an angle of about 25 degrees. These foremost portions are located past the bends 35a, 35a in the inserts 35, 35'. The length of overlap between the inserts 33, 35 and 33', 35' exceeds the height of orifices 117, 117'. The overlapping portions of these inserts are substantially parallel to each other. They insure that the liquid developer issues in predetermined directions and that the angle between the streams and the plane of film 21 remains substantially constant. The length of overlap between the inserts 33, 35 or 33, 35' does not exceed the distance between the bend 3511 or 35a and the intake end of the respective orifice 117 or 117'. If the flap 33a or 33a is pivoted in response to rotation of the screws 34 or 34', the width of the orifice 117 or 117' can be increased or reduced. Similar adjustments can be achieved by mounting the inserts 33, 33' or 35, 35' for movement toward and away from the plane of film 21. If the inserts 33, 33' are movable at right angles to the film plane, the planes of the front panels 31 31 are preferably normal to the film path.
The ducts 31b, 31b are accessible for cleaning in re sponse to removal of the inserts 35, 35'. The edges of the panels 31d, 31f and 31d, 31]" extend beyond the respective top panels 32, 32' (in a direction toward the film 21) to form two additional constrictions at the two ends of the channel 115A. The width of these constrictions is less than that of the constriction between the inserts 34, 35'.
The main body portion 31A of the upper container 31' carries a doctor blade or wiper 41 which extends close to the periphery of the transporting roll 22 and is secured to the container 31 by a plate 35A and one or more screws 40. The wiper 41 preferably consists of elastic synthetic plastic material and its purpose is to remove liquid developer from the roll 22.
FIG. 4 shows the container 31 from above with the inserts 33, 35 omitted. This illustration further shows a portion of the means for supplying liquid developer to the compartment or duct 31b. Tapped holes 31g and 3111 are provided in the main body portion 31A to accept screws which hold the top panel 32 (not shown). The
screw which enters the hole 31h simultaneously holds the insert 35. The tapped hole 311' receives one of the screws 34 for the insert 33.
The liquid supplying means includes a rectangular part of the main body portion 31A which accommodates a plastic block 36 of rectangular outline provided with a large-diameter passage 36a extending at right angles to the plane of film 21. This passage 36a is formed in the central portion of the block 36 and communicates with a radially extending port or passage 36b of identical diameter. The port 36b communicates with one end of the duct 31b by way of a suitable cutout which extends longitudinally of the container 31. The block 36 also serves as a means for preventing entry of liquid developer into the compartment 31c. The bottom panel of the main body portion 31A has a passage 31k which communicates with the passage 36a. The passage 31k in the bottom Wall of the main body portion 31A has a diameter which is considerably less than that of the passage 36a in the block 36' (see FIG. 5).
The remaining parts of the supplying means for liquid developer are shown in FIG. 5. The tank 101A has a bottom wall 42 provided with a hole 42a for a supply conduit 37. The conduit 37 has a shoulder 37a which abuts against the bottom wall 42. That portion of the conduit 37 which extends downwardly and beyond the hole 42a is threaded, as at 37b, to take a nut 38 which fixes the conduit in requisite position with reference to the tank 101A. The lower end portion of the conduit 37 is connected with a liquid-circulating pump by means of a hose, not shown. Such pump corresponds to the pump shown in FIG. 1.
The upper end portion of the supply conduit 37 has a counterbore 37c for a thin-walled sleeve 39 which is glued to the conduit and has two cutouts 39b, 39b which respectively register with ports 36b, 36b. The external diameter of the sleeve 39 equals the diameters of passages 36a, 36a in the blocks 36, 36. The lower container 31 surrounds the sleeve 39 and rests on the top face of the supply conduit 37. The container 31 rests on top of the container 31, i.e., the blocks 36, 36' a=but against each other and these blocks thus determine the width of aforementioned constrictions between the panels 31d, 31d and 31 31f. The passage 31k accommodates the stem of a screw 43 which meshes with a plug 39a in the upper end of the sleeve 39 and holds the blocks 36, 36' against movement away from each other.
The liquid developer fiows upwardly through the supply conduit 37 and through cutouts 39b, 39b of the sleeve 39 to enter the ducts 31b, 31b by way of the ports 36b, 36b. The cutouts 39b, 39b may but need not be of identical size. Their size depends on whether it is desired to supply to the ducts 31b, 31b equal or different quantities of liquid developer per unit of time. The sleeve 39 may accommodate a fitting angularly and/or axially adjustable metering sleeve (not shown) which can overlie larger or smaller portions of cutouts 39b, 39b to thus regulate the rate of liquid admission to the ducts 31b, 31b. Such metering sleeve can be provided with a relatively wide slot or cutout in the region of the upper cutout 39b and with a smaller-diameter portion in the region of the cutout 39b to insure that the liquid develops a pressure head before it enters the duct 31b and/or 31b.
The operation of the machine which embodies the structure of FIGS. 3 to 5 is as follows:
The leading end of the film 21 is introduced between the transporting rolls 22, 23 which advance the film through the channel A and into the range of transporting rolls 24, 25. A pump (not shown) supplies liquid developer into the lower end of the conduit 37. The liquid enters the sleeve 39 and flows through the cutouts 39b, 39b and ducts 31b, 31b to enter the channel 115A by way of the orifices 117, 117 in a direction counter to that in which the film 21 is transported by the rolls 22-25. The film has a certain stiffness which suffices to insure that its leading end does not abut against the panel 32 or 32' as soon as it advances beyond the constriction between the rear panels 31d, 31d. Thus, the film is immediately flanked by two liquid streams which insure that the surfaces of the film remain out of contact with the containers 31, 31'. The constriction between the inserts 35, 35' serves to center the leading edge of film 21 in the corresponding portion of the channel 115A; such constriction (in the zone between the bends 35a, 35a) further prevents entry of the leading edge into one of the orifices 117, 117'. The edges of the flaps 33a, 330' are more distant from the film path than the bends 35a, 35a; this also contributes to proper guidance of the leading edge of film 21 past and beyond the orifices.
The liquid issues from the channel 115A in the space between the rear panels 31d, 31d and the wiper 41 insures that the liquid cannot flow all around the upper transporting roll 22. Such liquid descends into the bottom zone .of the tank 101A by flowing along the edges of the film 21.
Since the ducts 31b, 31b take up only a small portion of the volume of the containers 31, 31, the operation of this machine is very economical and the machine is set for operation within a short interval of time following admission of liquid into the lower end of the supply conduit 37. This is of particular importance when the liquid is a developing solution which has a tendency to oxidize on contact with air. The efliciency of the machine is much higher than that of machines wherein the liquid flows in the direction of film transport. It was further found that liquid which flows countercurrent to the direction of film travel does not interfere with the transport of film through the channel 115A.
It will be noted that each of the containers 31, 31' has a single orifice which is adjacent to the discharge end of the channel 115A (i.e., to that end at which the film issues from the channel). Furthermore, the size of the orifice 117 or 117' can be changed to convert the machine of FIGS. 3 to 5 for treatment of different types of films. The cross-sectional area and the orientation of the orifice or orifices, combined with the output of the pump, determines the strength and the direction of liquid flow in the respective channel. As stated before, the cross-sectional area of the orifices 117, 117' can be adjusted by way of the inserts 33, 33 and/or 35, 35. Such adjustability enables the operators to select the intensity of treatment as a function of the type of film as well as in dependency on the output of the pump which delivers liquid to the conduit 37. Furthermore, the orifices 11-7, 117 can be cleaned without necessitating removal of the inserts 33, 33- and/or 35, 35'. As a rule, impurities which might accumulate in the conduit 37, sleeve 39, blocks 36, 36', ducts 31b, 31b and/or orifices 117, 117' can be expelled by increasing the width of orifices to a maximum value and by mechanically removing impurities which are intercepted between the inserts 33, 35 or 33, 35.
Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features which fairly constitute essential characteristics of the generic and specific aspects of our contribution to the art and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the claims.
What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims:
1. In a machine for liquid treatment of sheet-like Workpieces, particularly for developing of exposed photographic films, a combination comprising transporting means for advancing workpieces along a predetermined path and in a predetermined direction; a treating chamber defining a channel through which the workpieces advance during travel along said path, said chamber comprising two hollow containers respectively located above and below said path and said containers including panels flanking said channel from above and from below and each having at of liquid into said channel so that the liquid flows along the respective side of the workpiece in said channel and counter to said predetermined direction, at least a portion of the interior of each of said containers being in communication with the respective orifice and said containers further having abutting lateral panels; tank means accommodating said chamber and arranged to collect liquid which issues from said channel; means for supplying liquid into said chamber, including means for withdrawing liquid from said tank means and conduit means for admitting the thus withdrawn liquid into said containers; a lid arranged to float upon and to substantially cover the liquid which accumulates in said tank means; and pipe means arranged to convey liquid from said channel into the bottom zone of said tank means, said pipe means extending with clearance through an aperture provided in said lid.
2. In a machine for liquid treament of sheet-like workpieces, particularly for developing of exposed photographic films, a combination comprising transporting means for advancing workpieces along a predetermined path and in a predetermined direction; a treating chamber defining a channel through which the workpieces advance during travel along said path, said chamber comprising first and second containers respectively located above and below said path and having portions flanking said channel from above and having portions flanking said channel from least one liquid-discharging orifice for directing a stream of liquid into said channel so that the liquid flows along the respective side of a workpiece in said channel and counter to said predetermined direction, each of said containers further having an internal partition dividing its interior into a pair of compartments one of which communicates with the respective orifice, the volume of the other compartment of each of said pairs exceeding the volume of said one compartment and said containers further comprising means for sealing said other compartments from liquid; and means for supplying liquid to said one compartment of each of said containers.
3. A combination as defined in claim 2, wherein at least one of said orifices is an elongated slit extending transversely of said channel and wherein the respective container further comprises means for adjusting the eflective width of said slit, said adjusting means comprising a member detachably secured to the partition of the corresponding container.
4. In a machine for liquid treatment of sheet-like Workpleces, particularly for developing of exposed photographic films, a combination comprising transporting means for advancing workpieces along a predetermined path and in a predetermined direction; a treating chamber defining a channel through which the workpieces advance during travel along said path, said chamber comprising a pair of containers respectively located above and below said path and having portions flanking said channel from above and from below, each of said portions having at least one liquid-discharging orifice for directing a stream of liquid into said channel so that the liquid flows along the respective side of a workpiece in said channel and counter to said predetermined direction; tank means accommodating said containers; means for supplying liquid to said containers, including a substantially upright supply conduit extending upwardly through said tank means and arranged to feed liquid into passages provided in said containers in communication with the respective orifices, and a sleeve fitted into said conduit and extending into said containers to supply liquid to said passages, said sleeve having a closed end; and means for securing said containers to said conduit, including means for connecting the closed end of said sleeve to the upper one of said containers.
5. In a machine for liquid treatment of sheet-like workpieces, particularly for developing of exposed photographic film, a combination comprising transporting means for advancing workpieces along a substantially horizontal path and in a predetermined direction; a treating chamber defining a channel through which the workpieces advance during travel along said path, said channel having a receiving end and a discharging end located past said receiving end as considered in said predetermined direction and said chamber comprising portions flanking said channel from above and from below, each of said portions having at least one liquid-discharging orifice for directing a stream of liquid into said channel so that the liquid flows along the respective side of a workpiece in said channel and counter to said predetermined direction, all of said orifices being disposed nearer to said discharging end than to said receiving end and each thereof constituting an elongated slit extending transversely of said predetermined direction; means for supplying liquid to said chamber; and adjusting means for adjusting the effective width of at least one of said orifices, said chamber comprising two containers which are substantially mirror symmetrical with reference to the plane of said path and each of said portions forming part of a different one of said containers, said adjusting means comprising a pair of inserts flanking an orifice whose effective width is to be adjusted and means for moving at least a portion of at least one of said inserts with reference to the other insert to thereby change the efiective width of said last mentioned orifice.
6. A combination as defined in claim 5, wherein said 12 orifices are substantially mirror symmetrical to each other with reference to said plane.
7. A combination as defined in claim 5, wherein at least one of said inserts consists of elastic sheet material. 8. A combination as defined in claim 7, wherein said moving means is arranged to deform said one insert.
References Cited UNITED STATES PATENTS 3,413,904 12/1968 Friedel 9596 X 2,359,611 10/1944 Bolsey 9597 X 2,710,832 6/1955 Harr 9589 UX 3,143,056 8/ 1964 Limberger 9589 3,192,846 7/1965 Wright 9589 X 3,344,729 1 0/ 1967 Kitrosser 9589 3,348,526 10/1967 Neubauer 118410 3,372,630 3/1968 Schmidt 9594 3,405,626 10/1968 tFlCiShCl et al. 9594 3,405,627 10/ 1968 Day et al. 9594 3,461,788 8/1969 Tiger et al. 9589 X 3,461,843 8/1969 Noon 9589 X SAMUEL S. MATTHEWS, Primary Examiner 0 F. L. BRAUN, Assistant Examiner