US3852789A

US3852789A - Rapid access graphic arts film processor

Info

Publication number: US3852789A
Application number: US00365945A
Authority: US
Inventors: H Russell; W Hamilton; J Royston; G Stone; J Lin
Original assignee: Logetronics Inc
Current assignee: AFP ACQUISITION Corp
Priority date: 1973-06-01
Filing date: 1973-06-01
Publication date: 1974-12-03
Anticipated expiration: 1991-12-03
Also published as: GB1458095A; CH584915A5; NL7406788A; CA1019614A; JPS5017839A; JPS5426170B2

Abstract

A graphic arts film processor for rapidly processing large sheets of graphic arts films is disclosed. The processor uses transport modules having a plurality of rollers and cooperating belts arranged in semi-circular arcs. The film transport path defines a semicircular arc through each tank of processing fluid. The film enters and exits each tank of processing fluid along a tangent to each arc. A spray system is provided for increasing the circulation of the developer solution around the rollers during passage of the film through the last half of the developing module. The belt module is arranged to compensate for roller deflection. A belt tensioning mechanism cooperates with fixed reference points for the rollers to ensure that each roller turns about its true axis of rotation. The belts and rollers are driven in synchronism with one another in a common direction to thereby transport the film through the processing fluids.

Description

United StatesPatent 11 1 Russell et al. I

1451 Dec. 3, 1974 I RAPID ACCESS GRAPHIC ARTS FILM PROCESSOR [73] Assignee: LogEtronics lnc., Springfield, Va.

22 Filed: Junel, 1973 21] Appl.No.:36'5,945

Fairbanks et al 226/1 71 X 3.678.843 7/1972 Kohlcr ct ail. .1 95/94 R Primary E.\'aminer-Fred L. Braun Atrorney. Agent, or Firm-Elliott l. Pollock 57 ABSTRACT.

A graphic arts film processor for rapidly processing large sheets of graphic arts films is disclosed. The processor uses transport modules having a plurality of rollers and cooperating belts arranged in semi-circular arcs. The film transport path defines a semicircular are through each tank of processing fluid. The film enters and exits each tank of processing fluid along a tangent to each arc. A spray system is provided for increasing the circulation of the developer solution around the rollers during passage of the film through the last half of the developing module. The 'belt module is arranged to compensate for roller deflection. A belt tensioning mechanism cooperates with fixed reference pointsfor the rollers to ensure that each roller turns about its true axis of rotation. The belts and rollers are driven in synchronism with one another in a common direction to thereby transport the film through the processing fluids.

'10 Claims, 12 Drawing Figures PATENTELEEC sum gm 1 or a MJSNBG RAPID ACCESS GRAPHIC ARTS FILM PROCESSOR BACKGROUND OF THE INVENTION distribution patterns and'special developers. During the past two decades,- the introduction of graphic arts films with hardened emulsions and special developers has outdated the hand processing of film. Machine processing increases productivity, which leaves the operator free to concentrate uponexposure of the sensitized ma terial without having to be concerned over standardizing development, fixing, washing and drying procedures.

Graphic arts films and developers make use of the principle of infectious development wherein certain developing agents can form, during use, oxidation prod ucts which are powerful development accelerators. In conventional film developers, these oxidation products are quickly inactivated by reaction with the large amount of sulfite included as a preservative. However, in lithographic films, the concentration of sulfite is regulated and controlled. Thus, accelerators present in the solution encourage an appreciable boost inthe development rate, and grains which have not received grains. Since precision and image resolution are of utmost importance in the graphic arts industry, it is necessary to impose exact control on the developer constituents and the processing of the film.

In machine processing of graphic arts-films, bromide drag or adjacency effect impairs the consistency and quality of development. This problem usually occurs where large, heavily exposed areas on the negative are in close proximity to lightly exposed shadow dot detail. Because of the linear direction of film transport, the resulting agitation of the developer tends to occur only in that direction. The developer becomes exhausted, and an excessive amount of potassium bromide is liberated, remaining in the area as a result of the lack of cross-linear agitation. The bromide then acts as a restrainer and, wherever it is in contact with the film emulsion, retards any further reduction of silver to the metallic state.

When it-is desired toimprove the production rate of a film processor havinga given developing path length it becomes necessary to increase thefilm transport velocity in order to lower the machine throughput time. Such action reduces the amount of time spent by the film in the developing fluid and thus necessitates a compensatory increasein the temperature of the developing fluid in order to maintain the desired level of development activity. ltmay also result'in more rapidoxidation and exhaustion of the chemistry.

While a short transport path length will achieve a short throughput time, the achievement ofthis result presents serious problems. For example, asdevelopmentactivity is increased to achieve rapid processing, the amount of time spent by the film in traversing the in-air crossover path between the fluids in the developing and fixing tanks tends to result in degradation of both the image quality and contrast because such inair image development is performed with carried-over developer which quickly becomes oxidized and exhausted. This oxidation decreases the normal developer activity and increases the tendency to develop fog.

smaller effect on the image quality. Additionally,these films are intended to produce and promote higher than normal developer absorbtion through emulsion swelling', which results in the availability of added developer in the emulsion.

Unfortunately, these films do not function'in this way when they are intermixed with other films and/or developers. In designing a graphic arts processor which is compatible with a wide variety of films and processing chemistry, it is necessary to take other measures to reduce :bromide drag and the crossover effect.

In addition to the problems created by increasing the throughput or processing rate of a graphic arts processor, other difficulties are created in attempting to prothe oxidation products from adjacent developing cess sheets of extra wide graphic arts film. As the film width increases, the tr ansportwidth must also be increased, and this introduces new mechanical design problems. In wide film all roller processors the lack of roller straightness may become a major problem. The degree of roller deflection can, in some cases, actually exceed the thickness of the graphic arts film being processed, and this results in uneven pressure over the surface of the film as it is being developed. This" uneven pressure not only causes non-uniform development through pressure sensitization, but also varies the amount of agitation and developer action on the surface of the film.

ln roller-belt transport systems, this problem may be alleviated to some extent since the belts are tensioned against the rollers along the entire length'of the rollers. However, when the arrangement of rollers and belts is changed to shorten the path length through the developing solution, the problem of roller deflection assurnes new importance. Again, it is necessary to provide means for compensating for roller deflection to ensure that the pressure between the belts and rollers will remain uniform and consistent along the entire length of the rollers.

THE PRIOR ART ber of different matched chemistries and films; and

even systems which match the machine, the chemistry, and the film in an effort to achieve optimum results. However, it is desired to design processing machines which. will accept a wide range of graphic arts films, and different developer chemistries.

SUMMARY or THE INVENTION The present invention is intended for use in the rapid processing of extremely wide sheets of graphic arts film. The machine uses a plurality of belts androllers arranged to define a film path through the processor modules. A first transport section has a plurality of rollers mounted therein which define one side of a horizontal film transport path. This path is generally arcuate and defines a chord to middle ordinate ratio for the arc of at least 1 to l and preferably 2 to l or 3 to l. A

second transport section has a plurality of endless belts arranged below the roller section to define the other side of the film transport path. A tensioning means is create a hammock for the rollers and urge them upward against specific positional reference points. A plurality of reactor rolls are provided to define reference points for'the extra long rollers used in an extra wide film processor. Additionally. means are provided for increasing the circulation of the photographic solution in the developer tank to remove the reaction products from the-surface of the film and replace them with uniform developer solution. Specifically, the processing solution is circulated transversely of the rollers to provide fluid motion along the length of the rollers in addition to the linear agitation inherent in a roller processor. This transverse circulation is concentrated over an appropriate part of the development cycle to ensure that the processor is capable of developing all types of graphic arts films including those intended for rapid processing, and thos for which specialv compensation must be made to minimize the crossover effect.

The use ofa plurality of belts as a hammock to support the rollers obviates the problems caused by roller deflection. Thus, under tensioning, the belts provide constant pressure against each roller along its entire length in small increments, thereby distributing the amount of counter-pressure needed to compensate for roller deflection.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagrammatical and elevation view of the developer and fixer tanks of the present invention.

FIG. 2 is a diagrammatic view of the film path through the processor illustrating the crossover path.

FIG. 3 is :a sensitometric curve illustrating the contrast degradation resulting fromthe crossover effect.

FIG. 4 is a cross sectional view of .the spray means of the present invention. 1 I

FIG. 5 isa side view and partial cross section of the spray means of the present invention.

FIG. 6 is an isometric view of the spray rollers of the'present invention.

FIG. 7.is an isometric view of a transport section illustrating the belts and rollers with reactor rolls.

FIG. 8' is a top view of the drive means for rotating the belts and rollers.

FIG. 9'is a diagrammatic elevation viewofthe drive means of the present invention.

means and FIG. 10 is a diagrammatic view of an alternate means for driving the belts and rollers of the present invention.

FIG. 11 is a top view of the alternate means for driving the belts and rollers.

FIG. 12 is an exploded isometric view of the retarder tensioning means.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 illustrates in an elevation and diagrammatic view the film processor of the present invention including a developing tank 11 and a fixing tank 12. It is understood that in a conventional fllm processor a third tank would be added for washing, and a dryer would be added for drying the film. In the developing tank 11, a first transport section has mounted therein a plurality of rollers 13-19. These rollers are elongated hollow tubes fabricated of acrylic plastic or mica filled phenolic resin. Although the rollers could be fabricated from any inert material, it has been found that acrylic plastic will provide a relatively rigid and inexpensive roller for use in a film processor. The ends of these hollow tubes receive press-fitted plugs which seal the tubes and provide receptacles for press-fitted stainless steel shafts. These shafts are then journaled in plastic inserts mounted in end plates (not shown) for the first transport section.

Arranged around the first transport section is a second transport section which comprises a plurality of endless belts generally indicated at 20 which define therebetween a film transport path. The belts follow the radius of curvature defined by the rollers 13-19. In the present invention, the belts are mounted on a plurality of laterally spaced idler rollers arranged in a triangular configuration, such as those illustrated at 21-23. Each of the belts is tensioned by an idler roller 24 which is resiliently biased around pivot point 25 by means of tension arm 26. Thus each of the rollers 13-19 is supported along its entire length by a plurality of belts such as that illustrated at 20. These belts support the rollers and distribute the load of the rollers as r a plurality of small incremental loads.

point in the transport module, and has mounted thereon a plurality of reactor rolls 2835. These reactor rolls provide reference points to maintain the rotational position of each of the rollers 13l9. As the rollers are urged upwardly by the individual belts 20, they come into contact with the reactor roll means 27 which defines a pair of reference pointsfor each roller. These reference points are immediately adjacent the axis of rotation of the rollers to ensure that each roller rotates about its true axis of rotation and is not subject to roller deflectionrThe interaction of the belts and reactor rolls will be hereinafter discussed with respect to FIG. 7.

As asheet of graphic arts film 40 enters the processor, it is advanced by

feed rollers

41 and 42 into a plurality of laterally spaced deflector guides indicated at 43 which deflect the film downwardly between roller 13 and the belts 20. The film is fed into the film processor with the emulsion side up, and its first contact with either a belt or roller is below the surface of the processing fluid'indicated by numeral 44. The film is then lightly gripped between successive ones of the rollers 13-19 and the belts 20, with the emulsion side adjacent the rollers. It is advanced along the film path defined by the rollers and belts to an exit point between roller 19 and the belts 20.- During this period the rollers 13-19 act to gently agitate the developer on the emulsion surface of the film in the direction of linear transport. The spray means 45 provides for circulation of the developer in a lateral direction as will be hereinafter described. As the sheet of film 40a leaves the developing tank 11 its leading edge is deflected by baffle 145 to a pair of

squeegee rollers

46 and 47. The upper squeegee roller 46 is a solid stainless steel-pressure roller, while the lower roller 47 is comprised of a rubber covered stainless steel roller.

Rollers

46 and 47 remove the excess developer from the surface of film 40a to reduce the transfer of developing fluid to the fixing tank 12. After passing through the squeegee rollers 46-47 the film is then directed by a plurality of laterally spaced guides 48 into the transport path through the fixing fluid. The curved shapes of the

guides

43 and 48 are developed empirically, based on the assumption that film stiffness is always sufficient to permit the first one and a half linear inches of film back from the leading edge of each sheet to be essentially straight. Using this assumption, the curvatures of the guide edges are determined by effecting plots for each half inch increment of advance of the film leading edge. The curvature thus plotted or set is used to form the-contours of

guides

43 and 48 and enables a sheet of film to be transported from one tank to the next with only its leading edge in contact with the guide plates, with the remainder of the sheet being freely spaced from the guide edge. This avoids any scratching or marking of the sheet during its passage into or out of each tank, and minimizes encrustation of the guide plates, which might otherwise cause scratching as a result of thecrystallization of chemicals transferred to the guide plate edges from the surface of the film. 1

In the fixing tank 12 the transport path is defined by rollers 49-55, and a plurality of laterally spaced belts 56. Since the film is not pressure sensitive during fixing,

it is not essential to provide reactor rolls or reference points for theroller transport section mounted in this tank. After the film is transported through the fixing tank 12, it again passes through a pair of squeegee rollers (not shown) similar to

rollers

46 and 47 and is deflected into the wash tank by a set of laterally spaced baffles (not shown) similar to baffles 48.

The actual processing time for the film is adjustable, and may encompass approximately a 4 to 1 ratio.For rapid development it is possible to move a sheet of film throughthe developing, fixing and washing tanks, and the dryer, in a dry to dry elapsed time of approximately l minute- For films or processing techniques requiring extended "development, the drive means for the belts and rollers may be slowed to provide a four minute dry to dry processing time. If a one minute'time interval is metal 38 and the path length through the fixing fluid is indicated by the numeral 39. As was discussed previously, the crossover period has a significant effect on image quality in lithographic film processing. During this portion of the film travel, the film has on its surface a thin layer of developer, and has within the emulsion some of the developer chemistry. The surface layer of developer is rapidly exhausted and has no chance to be replenished by fresh developer since the film is out of solution. The rate of image development in tank 11 varies, depending upon the pH and concentration of the developing agents, the temperature of the solution, the processing time, and the speed and nature of the photographic emulsion. However, when the film leaves tank 11, the development rate will decrease during the crossover period, regardless of the reaction taking place in the path 37. As the carried-over developer be comes exhausted, an excessive amount of potassium bromide is liberated and acts as a restrainer to prevent any further reduction of silver to the metallic state. As a result, the development reaction is distorted during the crossover and the exhausted developer degrades film image quality.

The crossover effect is graphically illustrated in FIG. 3. This figureshows development of KodaLith Type 3 film in .KodaLith RT developer in a conventional prior art processor. Graph A illustrates the sensitometric curve obtained by processingfilm for 1 minute and 35 seconds. Curve B illustrates the sensitometriccurve obtained with a 2 minute development wherein the additional 25 seconds of development took place in the processors crossover section. The degradation of the development in the toe region provides an image of lower contrast that can be detected by the eye as having poor dot quality.

As has been pointed out previously, matched films and developers have been manufactured which exhibit much higher induction rates at the beginning of the development cycle, resulting in rapid image development during the initial part of the cycle, and much slower development by the time that the cycle is terminated. However, more conventional lithographic developers are characterized by a slow development rate during the first part of thecycle with the development rate gradually increasing to a maximum at the end of the cycle. Thus, in designing a processing apparatus for use witha wide variety of films and developers it is necessary to compensate for the crossover effect inherent in machine processing.

1n the processor of the present invention, each of the rollers 13-19 gently agitates the emulsion of the film as it passes through the developing module. However, this agitation is inherently linear because of the linear movement of the film past the rollers. ln' addition, exhausted developer is trapped in the regions immediately behind the rollers and further inhibits vigorous development. To reduce this effect the developer fluid in'tank 11 is filtered, recirculated and returned to spray means 45 which provides lateral circulation of the recirculated liquid along the rollers at a plurality of points transverse to the direction of travel of the film. High quality machine processing of photographic materials depends upon uniform circulation of the solution and uniform agitation at the emulsion surfaceCirculation in this sense is defined as the mixing of the reaction products with the bulk of the processing solution. Agitation is defined as the uniform removal of these prodlated developer on

rollers

16, 18 and 19. The axes of the openings in

rows

45a and 45c are angled towards one end of at least two of the processor rollers and the axes of the openings in the alternate intervening row 45b are angled towards the other end of at least one of the other rollers. This creates the transverse swirling effect illustrated diagrammatically in FIG. 6. In one form of the invention three rows of holes were formed with the

openings

45a, 45b and 45c ahgledtowards the last, the next to last, and the bottom roller, respectively, in the developer tank. The fluid flow through each row of holes is alternately cross-swirled, as illustrated in FIG. 6. Depending upon the characteristics of the film and chemistry being utilized, it may be desirable to provide for realignment of spray tube 45 to transfer the points of fluid impingement to other rollers within the module. The spray from spray means 45 is angled towards the rollers and assists in the lateral 'circulation of the developing fluid as the rollers rotate. This lateral circulation aids in the removal of exhausted developer trapped directly behind or on the processing rollers. The counter-flow action produced byeach row of openings, when combined with the placement of the exit openings, also sets in motion acounter-swirling agitation between the rollers which further aids in the rapid development of the film throughout its travel through the last half of the transport path in the developing tank.

The crossover region denoted by numeral 38 in FIG. 2 is important in the design and construction of the processor. It has been found that image degradation will occur in rapid processing if the crossover path length exceeds one third of the path length 37 through the developing fluid, regardless of the activity level or temperature of the developer. While the cross-over effect is minimal inconventional deep tank development, such deep tank development makes it impossible to provide dry to dry times on the, order of l minute. In order to obtain rapid access processing with a dry to dry time of 1 minute, it is necessary to provide the shortest possible-path length for the film travel through the developer and fixer tanks. In the design and-construction of the invention described above, it was found that a semi circular path subtending a 90 angle and having a'chord to middle ordinate ratio of approximately 2 to 1 resulted in a path length long enough to provide for the proper processing of existing graphic arts film with existing chemistries. yet minimized the crossover effects. This semicircular path describes a chord of a circle through the fluid with the chord length represented as the distance C-D in FIG. 2, and the middle ordinate distance is- E-F. The film path may be described as an arcuate' path subtending a 90 arc,

wherein the path at the beginning and'end of the mod- .ule traverses tangents which are 90 to one another. As illustrated in FIG.2, angle A, angle B and angle C are approximately'90", as are the intersections of tangents 103 and 104-with radii 101-102 and 105-106. The intersecting

tangents

103 and 104 describe the film path as the film leaves the developing solution and enters the fixing solution. 7

The processor of the present invention is intended to be used with the wide variety of graphic arts films with different emulsions, and different developing agents. It is designed to be used with different thicknesses of graphic arts film and must therefore be suitable for processing film with a wide variety of intermixes between emulsions and chemistries. It would be possible to use a broader range of chord to ordinate ratios, but as the relative length of each processor section increases, the overall length of the machine increases. When a proc'essing machine is designed to handle extra wide sheets of graphic arts film, it becomes virtually impossible to adapt the machine to existing dark room space if it has,

a large length to height ratio in each section. However, the chord to ordinate ratio may be as small as l to l or as large as 6 to 1 without changing the essential characteristics of the machine.

One of the particular advantages resulting from the chosen length to height ratio is the belt arrangement diagrammatically illustrated in FIG. 7. This configuration allows the plurality of belts 200, b and c to support the rollers across their length at a plurality of points and thereby eliminate roller unstraightness or deflection. As was pointed out previously, a small amount of roller deflection in the developer section of the film transport can be very detrimental to the processing of graphic arts film. Such film is sensitive not only to transport agitation, but also to transport pressure. Many graphic arts films are extremely thin and a roller deflection of 2 or 3 thousandths of an inch will cause an appreciable difference'in the development of the film. The longer the rollers or the wider the film to be processed, the more severe the problem resulting from roller deflection.

FIG. 7 is a diagrammatic view, wherein the belts 20a,

20b, and 20c have been separated to more clearly show their relative support of rollers 13-19. lnthe actual construction of a machine capable of processing 48 inch wide film, each of the

belts

20a, 20b, and 200 is approximately 1 inch in width and is supported at three points by crowned rollers. Each of the rollers 21a-c, 22a illustrated .in FIG. 7 is approximately l /z inches in diameter, and 1 inch in width. The rollers 21a-c 22a-c are mounted on centers approximately one and a quarter inches apart, across the entire width of the transport module. Thus as many as 35 to 40 belts will be found in a processor capable of processing 48 inch wide film. The belts are tensioned by means of a tensioning roller 24 which is urged outwardly against the belts as illustrated by the arrows in FIG. 7 and FIG. 1. The tension roller is resiliently biased by means of tension arm 26 (illustrated in FIG. 1) to bring each of the belts into tangential contact with the rollers of the roller section. Each of the belts then provides tangential support for the rollers and urges the rollers toward their fixed positional reference points defined by rolls 28-35.

The plurality of reactor rolls 28-35 are mounted approximately midway across the developing tank transport section. The rolls 28-35 are mounted for rotation between a pair of

end plates

57a and 57b. The

end plates

57a and 57b are secured to a large cross beam 58 which extends widthwise across the processor module from one module side frame to the other. The cross beam 58 is relatively rigid and provides a fixed reference for the mounting of rolls 28-35. As each of the rollers 13-19 is biased inwardly by the

belts

20a, 20b and 20c, it contacts the reactor rolls to provide two separate contact referencepoints. The reference points are adjacent the axis of rotation of the rollers. Thus each point of contact between the rollers 13-19 and the reactor rolls 28-35 becomes a fixed reference point for use inaligning the rollers 13-19 with their true axis of rotation. Since in a 48-inch processor, each of the rollers 1349 is supported by the spaced-apart belts for approximately 35 to 40 inches of its 48-inch length, the pressure applied at any. point along rollers 13-19 is minimized by distributing it over a plurality of incremental points. This prevents any one of the

belts

20a, 20b or 20c from generating enough pressure to cause pressure sensitization of the film emulsion as it passes through the film transport.

FIGS-8 and 9 represent the drive means used in the preferred embodimentof the invention. Referring to FIG. 9, the drive means rotates a shaft 60 which, in turn, drives worm gear 61 and its associated worm gear 62. This rotation is then translated through idler gear 63 to a main drive gear 64. Although it is possible to use the film transport of the present invention without driving each of the rollers individually, it has been found that more consistent results are achieved if each of the rollers is independently driven. Drive gear 64 is fixedly attached to shaft 65 (illustrated in FIGS. 8 and 9).- Drive gear 64 also drives an endless means 67 which provides a positive drive for gear 68 which is fixedly attached to shaft 66 (illustrated in FIGS. 7 and 8).

Shafts

65 and 66 carry the plurality of rollers 22c-c and 21a-c diagrammatically illustrated in FIG. 7.

Shafts

65 and 66 amount of drag tension applied to roller 78a and belt a and thumbscrew 82b provides for the application of drag tension to roller 78b and belt 2012.

FIG. 12 illustrates diagrammatically in an exploded j view the arrangement used to tension the belts. In this embodiment, thumbscrew 82a applies pressure on shaft 86 to urge the retarder rollers 81 into engagement with reference rollers 78a & b. This pressure is exerted against the reference rollers by yoke 85 and shaft 87.

A slack portion of the belt is present between

idler rollers

79 and 80, as illustrated at 83. Since the belts are positively pulled through the transport path by the Thus any variances in'belt thickness are inconsequenprovide the drive forthe rollers which, in turn, provide a positive drive for the

belts

20a, 20b, and 200.

The endless means 67 may include a timing belt, chain,or other flexible positive drive such as a toothed V belt. A double sided timing chain has been used in the illustration of FIG. 9 since it is driven on the inside I to drive rollers I3-l9 with the surface friction generated by the belts 20a, b, and c, it is desirable in machines of extraordinary width to provide a supplemental drive for these rollers.

The second embodiment of the invention is illustrated in FIGS. 10, 11 and 12. In this embodiment, a capstan drive'roller 76 is provided to drive the peripheral surface of the beltsthat, come into contact with the film. The capstan drive rollers 76 are positioned against an idler roller 76a which isbiased against the capstan drive roller 76 to provide a positive drive for the belts 20a, 20bland, 20c. I v

The drive .roller 76 and a set of reference rollers 78 are provided at the end and beginning of the transport path respectively to urge each of the belts 20a, b and c into tangential contact with the rollers 13a-19a. Two additional sets of

idler rollers

79 and 80 are provided to returnthe belts 20a, b and c to the reference rollers Each of the belts 200, b and c is tensioned by means of an individual retarding roller 81 whichis biased to wards the reference rollers 78. A thumb screw 82 provides for the individualadjustment of each of the retarding rollers 81 against its associated belt. 'Thumb screw 82a illustratedin FIGS. 11 and 12) adjusts the tial since capstan drive 76 is driving the surface of the belt that comes into contact with the base surface of the film at a constant peripheral speed.

The transport system described above, when constructed in accordance with the present invention, permits the automatic processing of extremely wide sheets of film, and the sequential processing of film sheets of various different thicknesses. Major economies in manufacture are achieved due to the simplicity of the belt and roller transport system, the ease of assembly of the component parts, and the fact the system lends itself to automatic moldings and extrusions using acrylic, polyvinyl chloride, or other plastics formany of its parts. Each of the major components of the transport sections is removable to facilitate the maintenance or repair of the section, when required. For example, the entire roller transport section is removable as one unit. Likewise, the entire belt transport section is removable from the developing tank or the fixing tank. The modular assembly also permits the removal of an entire developing or fixing transport if necessary. By reason of all of these factors, and others whichwill be apparent from the preceding description, the overall system achieves significant improvement in reliability, consistency, operation, and maintenance when compared to other systems of the prior art.

While we have thus described the preferred embodiments of the present inventiomother variations will be suggested to those skilled in the art. It must therefore be understood that the foregoing description is meant to be illustrative only and not limitative of the present invention; and all such variations and modifications as are in accord with the principles described are meant to fall within the scope of the appended claims.

Having thus described our invention, we claim:

1. A graphic arts film processor for rapidly processing sheets of graphic arts film, which comprisesa. a first transport section having a plurality of rollers arranged to define one side of a horizontal arcuate film transport path, said path having a chord to middle ordinate ratio of at least 1:1,

I b. a second transport section having a pluralityof endless belts arranged in side-by-side relation to one another below said rollers of said first transport section to define the other side of said film transport path, each of said belts being associated with a plurality of said rollers and extending along a horizontal arcuate also having a chord to middle ordinate ratio of at least 1:1 whereby each said belt is arranged to follow the radius of curvature of said one side of said arcuate film transport path defined by said plurality of rollers,

c. means for urging each of said belts into tangential contact with a plurality of the rollers of said first transport section to provide a positive drive therebetween for advancing sheets of film along said transport path, said belts being operative to support said rollers to prevent deflection of said rollers,

d. first and second fluid processing tanks, said first and second transport sections mounted within said first fluid processing tanks,

e. first guide means for guiding sheets of graphicarts film into said arcuate film transport path with the emulsion side of said film in contact with the rollers of said first transport section,

f. second guide means for guiding sheets of graphic arts film from said first tank to said second tank after said film had been transported through said arcuate transport path, I v 1 g. means for supplying and circulating said photographic processing fluid in said first tank to remove exhausted processing fluid from the surface of said film,

h. means for driving said belts and rollers to cause each to rotate in synchronism with one another in a common direction and thereby transport said film through said processing fluids.

2. A graphic arts film processor as claimed in claim 1 wherein said means for supplying and circulating said fluid is concentrated in the last half of the transport path, immediately before said film leaves said processing fluid.

3. A graphic arts film processor as claimed in claim 2 wherein said means for supplying and circulating said fluid comprises a spray means which defines a plurality of openings arranged in rows along the longitudinal axis of said spray means, the axes of the openings defined in at least one of said rows being angled towards one end of said rollers with the axes of the openings in the other of said rows being angled towards the other ends of said rollers.

4. A graphic arts film processor as claimed in claim 1 wherein said rollers and belts are driven by a common drive, said drive including an endless means for simultaneously rotating said rollers and said belts.

5. A graphic arts film processor as claimed in claim 1 wherein said means for urging said belts into tangential contact with said rollers and said means for said belts and rollers comprises a. retarder means arranged to retard the movement of said belts adjacent the beginning of said film transport path, I b. capstan drive means to drive the surface of the belts contacting the film, said drive means being located adjacent the end of said film transport path. 6. A graphic arts film processor as claimed in claim 1 which further comprises means to compensate for driving roller deflection comprising a reference means mounted above said rollers to define a plurality of reference points for said rollers adjacent their axis of rotation, said second transport section having said belts tensioned to support said rollers along the film path and urge said rollers into contact with said reference means.

7. A graphic arts film processor as claimed in claim 6 wherein said reference means comprises a plurality of reactor rolls, each of said rollers contacting at least two reactor rolls to define said reference points.

8. A graphic arts film processor for rapidly processing sheets of graphic arts film, which comprises a. a first transport section having a plurality of rollers,

said rollers defining one side of a horizontal and arcuate film transport path, said path having a chord to middle ordinate ratio of at least 1 to l,

b. a second transport section having a plurality of endless belts arranged below said roller section to define therebetween a film transport path, said belts being mounted on a plurality of laterally spaced rollers, and arranged to follow the radius of curvature defined by the plurality of rollers in said first transport section, .refere'nce means mounted above said rollers of said first transport section to define a plurality of reference points for said rollers adjacent their axes of rotation,

d. means for urging said belts into tangential contact with the rollers of said first transport section to provide a positive drive therebetween for advancing sheets of film along said transport path, said belts also supporting said rollers along said film path and urging said rollers into contact with said reference means,

e. first and second fluid processing tanks, said first and second transport sections mounted within said first fluid processing tanks,

f. first guide means for guiding sheets of graphic arts film into said arcuate film transport path with the emulsion side of said film in contact with the rollers of said first transport section,

g. second guide means for guiding sheets of graphic arts film from said first tank to said second tank after said film has been transported through said arcuate transport path,

h. means for supplying and circulating said photographic processing fluid in said first tank to remove exhausted processing fluid from the surface of said film.

9. A graphic arts film processor as claimed in claim 8 wherein said means for supplying and circulating said fluid are concentrated in the last half of the transport path, immediately before said film leaves said processing fluid.

10. A graphic arts film processor as claimed in claim 9 wherein said means for supplying and circulating said fluid comprises a spray means which defines a plurality of openings arranged in rows along the longitudinal axes of said spray means, the axes of the openings defined in alternate rows being angled towards one end of said roller section, and the axes of the openings of intervening rows being angled towards the other end of said roller section.

Claims

1. A graphic arts film processor for rapidly processing sheets of graphic arts film, which comprises a. a first transport section having a plurality of rollers arranged to define one side of a horizontal arcuate film transport path, said path having a chord to middle ordinate ratio of at least 1:1, b. a second transport section having a plurality of endless belts arranged in side-by-side relation to one another below said rollers of said first transport section to define the other side of said film transport path, each of said belts being associated with a plurality of said rollers and extending along a horizontal arcuate also having a chord to middle ordinate ratio of at least 1:1 whereby each said belt is arranged to follow the radius of curvature of said one side of said arcuate film transport path defined by said plurality of rollers, c. means for urging each of said belts into tangential contact with a plurality of the rollers of said first transport section to provide a positive drive therebetween for advancing sheets of film along said transport path, said belts being operative to support said rollers to prevent deflection of said rollers, d. first and second fluid processing tanks, said first and second transport sections mounted within said first fluid processing tanks, e. first guide means for guiding sheets of graphic arts film into said arcuate film transport path with the emulsion side of said film in contact with the rollers of said first transport section, f. second guide means for guiding sheets of graphic arts film from said first tank to said second tank after said film had been transported through said arcuate transport path, g. means for supplying and circulating said photographic processing fluid in said first tank to remove exhausted processing fluid from the surface of said film, h. means for driving said belts and rollers to cause each to rotate in synchronism with one another in a common direction and thereby transport said film through said processing fluids.

5. A graphic arts film processor as claimed in claim 1 wherein said means for urging said belts into tangential contact with said rollers and said means for driving said belts and rollers comprises a. retarder means arranged to retard the movement of said belts adjAcent the beginning of said film transport path, b. capstan drive means to drive the surface of the belts contacting the film, said drive means being located adjacent the end of said film transport path.

6. A graphic arts film processor as claimed in claim 1 which further comprises means to compensate for roller deflection comprising a reference means mounted above said rollers to define a plurality of reference points for said rollers adjacent their axis of rotation, said second transport section having said belts tensioned to support said rollers along the film path and urge said rollers into contact with said reference means.

8. A graphic arts film processor for rapidly processing sheets of graphic arts film, which comprises a. a first transport section having a plurality of rollers, said rollers defining one side of a horizontal and arcuate film transport path, said path having a chord to middle ordinate ratio of at least 1 to 1, b. a second transport section having a plurality of endless belts arranged below said roller section to define therebetween a film transport path, said belts being mounted on a plurality of laterally spaced rollers, and arranged to follow the radius of curvature defined by the plurality of rollers in said first transport section, c. reference means mounted above said rollers of said first transport section to define a plurality of reference points for said rollers adjacent their axes of rotation, d. means for urging said belts into tangential contact with the rollers of said first transport section to provide a positive drive therebetween for advancing sheets of film along said transport path, said belts also supporting said rollers along said film path and urging said rollers into contact with said reference means, e. first and second fluid processing tanks, said first and second transport sections mounted within said first fluid processing tanks, f. first guide means for guiding sheets of graphic arts film into said arcuate film transport path with the emulsion side of said film in contact with the rollers of said first transport section, g. second guide means for guiding sheets of graphic arts film from said first tank to said second tank after said film has been transported through said arcuate transport path, h. means for supplying and circulating said photographic processing fluid in said first tank to remove exhausted processing fluid from the surface of said film.