US3785269A

US3785269A - Automatic film processor having switchable transport path

Info

Publication number: US3785269A
Application number: US00357739A
Authority: US
Inventors: M Morioka
Original assignee: Logetronics Inc
Current assignee: AFP ACQUISITION Corp; LOG ELECTRONICS Inc
Priority date: 1972-10-31
Filing date: 1973-05-07
Publication date: 1974-01-15
Anticipated expiration: 1991-01-15
Also published as: JPS53697B2; JPS4967627A; NL7308902A

Abstract

An automatic film processor having a transport system for normally transporting sheets of film to be processed through a series of treatment stations in predetermined sequence, includes a movable guide element for altering the transport path to vary the sequence of processing steps for a selected sheet of film. The selected sheet can be provided with a distinctively colored leader, the presence of which is detected by a color-sensitive control system operative to alter the transport path, e.g., to divert the selected sheet of film away from the drier in the film processor and deliver it in wet condition to a catch tray.

Description

1451 Jan. 15, 1974 United States Patent 11 1 Morioka 3,472,143 10/1969 Hixon et a1. 95/89 R 3,639,061 2/1972 O'Brien et 95/89 R X 3,698,306 10/1972 Fairbanks............................ 95/94 R Springfi ld, Primary Examiner-Fred L. Braun Attorney-Elliot I. Pollock Assignee: Log Electronics Inc [57] ABSTRACT An automatic film processor having a transport system [22] Filed: May 7, 1973 21 Appl. No.2 357,739

for normally transporting sheets of film to be pro- [30] Foreign Application Priority Data cessed through a series of treatment stations in prede- Oct. 31, 1972 termined sequence, includes a movable guide element for altering the transport path to vary the sequence of [52 us. 95/94 R, 95/89 R, 226/28 processing steps for a selected sheet of film The 51 Int. Cl. G03d 3/12 lected sheet can be provided with a distinctively [58] Field of 95/89 R, 94 R; ored leader, h p n f hich is de ected y a 226/27, 23; 355/10, 106 color-sensitive control system operative to alter the transport path, e.g., to divert the selected sheet of film away from the drier in the film processor and deliver it in wet condition to a catch tray.

[56] References Cited UNITED STATES PATENTS 2,913,974 11/1959 Sabel et a1. 95/94 R 10 Claims, 4 Drawing Figures PATENIEU JAN 15197 AUTOMATIC FILM PROCESSOR HAVING SWITCIIABLE TRANSPORT PATH BACKGROUND OF THE INVENTION Thelpresent invention relates to an improved form of automatic film processor comprising a transport system adapted to convey sheets of film in succession through a developing tank, a fixing tank, and a wash tank to a drier, and is more particularly concerned with an automatic switching apparatus which is incorporated in the transport system for selectively interrupting the normal transportsequence in respect to a selected sheet of film to divert said selected sheet of film out of the normal transport path.

Automatic film processors are now well known for the processing of lithographic film in graphic arts. Such processors are widely employed since they automatically perform the desired film processing steps in a desired, predetermined sequence once a sheet of film to be processed is fed into the equipment, and also because the quality of processing is extremely stable. Usually, once a sheet of film is fed into the processor, the sheet is transported from .one to another treatment station to cause the sheet to be developed, fixed, washed, and dried without interruption; and the processed sheet of film is thereafter ejected from the processor in completely finished and dried condition.

While this completely automatic nature of known film processors is highly desirable, it is, under some circumstances, a disadvantage. For example, it is sometimes highly desirable to obtain access to a processed sheet of film immediately after the wash step of the process, while the film sheet is still wet. Film which carries a half-tone image, for use in printing pictures in various degress of density, is often retouched by so-called dot etching techniques after it is processed. This retouching is done by manually applying a reducer fluid to necessary parts of the image, leaving said fluid in place for a prescribed period of time, and thereafter washing excessive reduction fluid off the film to terminate the reduction process. If the film to be retouched is obtained in dry condition from the automatic film processor, it must be washed again during the retouching process; and the prior drying step performed in the automatic film processor is actually wasted. A more serious difficulty, however, arises in that some film base materials may be subject to shrinkage, producing a decrease in the true dimensions of the image thereon, as a result of recurrent washing and drying.

For the reasons given above, it is desirable, in such cases, to be able to switch the transport path so that a sheet of film which must be subject to dot etching can be diverted from its normal transport path, and removed from the processor, immediately after the wash step has been performed in the processor. Such alteration in the transport path gives rise to other problems, however. More particularly, when a large number of sheets of film are being processed successively in an automatic film processor, and when the different sheets include both half-tone and other images respectively, it becomes extremely difficult to switch the transport system in a fashion which will properly discriminate between the different types of image bearing sheets of film. This difficulty is caused by the fact that it takes between two and three minutes for each of the developing, fixing, washing, and drying steps to be performed in an automatic film processor, i.e., a total of six to nine minutes may elapse between the time a particular sheet of film is fed into the processor and the time it has completed the wash step. Consequently, when sheets of film having different types of images thereon are fed into a processor successively, it is impossible to switch the transport system concurrent with the feeding in of a sheet of film of given type since this could disrupt the processing steps which must be performed in respect of a sheet of film of different image type earlier fed into the processor and still being processed. This difficulty could be overcome, of course, by having an operator continually in attendance to manually switch the transport system at a proper time so as to divert a selected sheet of film away from the drier after the sheet has been washed; but this type of control is not practical since it is troublesome, and since it detracts from and actually nullifies the labor-saving features which characterize an automatic film processor.

The present invention is accordingly concerned with a mechanism which is automatically operative to alter the transport path of a selected sheet of film when such alteration is desirable, thereby to eliminate any need for manual control of the transport path, and which is operative to divert a selected sheet of film out of its normal transport path without disrupting or altering the transport path for other sheets of film being processed.

SUMMARY OF THE INVENTION In accordance with the present invention, the trans port system in an automatic film processor is modified to include, at a preselected position along the transport path, a movable guide element, e.g., a pivotally mounted element, adapted to be moved by an electrically energizable solenoid. When the solenoid is not energized, and the element is in its quiescent position, a sheet of film is transported in normal sequence through the various treatment steps in the processor. However when the solenoid is energized, the guide element is respositioned to divert a sheet of film out of said normal transport path into an alternative path. In a preferred embodiment of the invention, the guide element is located between the wash tank and drier in the processor so that when the element is in its quiescent position a sheet of film is directed from the wash tank into the drier, and when the guide element is repositioned the sheet of film is diverted away from the drier and into a catch tray disposed on the exterior of the processor.

Energization of the solenoid, to selectively alter the transport path, is controlled by a sensor mechanism disposed closely adjacent to the guide element at a position upstream thereof, and responsive to an indicium of predetermined character on a selected sheet of film being processed for operating said guide element to its diverting position. In a preferred embodiment of the invention, a leader having a distinctive color is attached to a sheet of film whose transport path is to be altered; and the sensor mechanism comprises a color sensitive photoelectric system which detects the presence of the distinctively colored leader as it is transported toward the movable guide element, to operate the guide element to its diverting position as said leader and the sheet of film attached thereto approach said guide element.

BRIEF DESCRIPTION OF THE DRAWINGS The foregoing objects, advantages, construction and operation of the present invention will become more readily apparent from the subsequent description and accompanying drawings wherein:

FIG. 1 is a diagrammatic view, in partial section, of an automatic film processor transport system incorporating the present invention;

FIG. 2 diagrammatically illustrates the movable guide element and associated control mechanism of the present invention;

FIG. 3 depicts a sheet of film having a colored leader attached thereto for controlling the switchable transport mechanism of the present invention; and

FIG. 4 is a block diagrammatic circuit representation, of the sensor mechanism of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a vertical cross sectional view illustrating the film transport system of an automatic film processor incorporating the automatic switching apparatus of the present invention. The processor includes one or more developing tanks (not shown) followed by one or more fixing tanks (also not shown) which are in turn followed by a wash tank 1 containing water 3. Te wash tank 1 includes a plurality of rollers such as 4 and-6 associated with belts and 7 constituting a portion of a conveyor system. Film which is transported from the fixing tank into wash tank 1 is accordingly washed in said tank and is thereafter normally conveyed to a drying tank 2 which includes a further portion of the conveyor system, comprising rollers such as 8, 10, 12 operative to drive associated belts such as 9, 11, 13.

The foregoing elements of the processor are conventional. A sheet of film to be processed is fed into the processor at a position significantly upstream of wash tank 1, and is then transported by other portions of the transport system into and through the developer tank(s), then into and through the fixing tank(s), and is thereafter transported into wash tank 1 at a position upstream of roller 6. The developed and fixed sheet of film is thereafter moved downwardly into the water bath 3, is turned around at a position near the bottom of said bath, and is then directed to a position between belts 5 and 7 and, being sandwiched therebetween, is pulled vertically upward through the water bath 3 and out of wash tank 1. The washed sheet of film thereafer proceeds vertically along a guide 14 and is deflected thereby into a horizontal plane so as to pass between a first pair of

squeegee rollers

15, 16 along

guide elements

22, 24 and thence through a further pair of

squeegee rollers

17, 18. Water which is wiped from the surfaces of the film sheet is discharged from the squeegee rollers into a tray 19. The sheet of film is then deflected downwardly by a further guide so as to enter the drying tank 2 at a position between belts 9 and 11, is driven downwardly into said tank between belts 9 and 11, is turned around at the bottom of the tank by a further guide mechanism (not shown) and is thereafter sandwiched between belts 11 and 13 so as to be moved upwardly through the drying tank. The dried sheet of film then proceeds out of the drying tank along the surface of a still further guide 21, and is deflected into a horizontal plane so as to exit from the film processor.

The roller/belt elements shown in FIG. 1, similar such elements (not shown) associated with the developing and fixing tanks, and the various squeegee rollers constitute, together, a conveyor or transport system, and the several portions of that system operate synchronously with one another and in the direction indicated by the various arrows shown in FIG. 1.

In accordance with the modification of the present invention, the guide structure provided between the pairs of

squeegee rollers

15, 16 and 17, 18 is made up of two guide elements, i.e., a fixed position guide element 22, and a movable guide element 24. The movable guide element is mounted for pivotal'movement on a shaft 23, and is adapted to be selectively moved to the oblique position shown in broken line in FIG. 1 so as to deflect a sheet of film passing along guide 22 away from the drier 2 and, instead, toward a pair of further drive rollers 33, 34. When movable guide element 24 is in its broken-line position, therefore, a washed sheet of film is transported from wash tank 1 through

squeegee rollers

15, 16 along guide 22, and is then directed upwardly along the upwardly pivoted guide element 24 toward the nip of drive rollers 33, 34, whereafter the washed sheet of film, still in a wet state, passes over a further guide element 35 into a catch tray or pan 36 located on the top cover 37 of the automatic film processor.

The guide structure which is disposed between the paired

squeegee rollers

15, 16 and 17, 18 is shown in further detail in FIG. 2. The horizontal, fixed position -guide 22 comprises a plurality of bars disposed in spaced relation to one another to define a horizontal plane along which the washed sheet of film is transported by the action of

squeegee rollers

15, 16. Shaft 23 is mounted in said plane, and has a plurality of spaced bar-type guides 24 attached thereto at their inner ends respectively. A crank arm 38 is attached to one end of shaft 23, and said arm 38 is provided with a groove which receives a pin attached to the plunger 40 ofa solenoid 39. When the solenoid is in its unenergized state, the various elements assume the position shown in full line in FIG. 2; but when solenoid 39 is energized, plunger 40 retracts to reposition crank arm 38 to the position shown in broken line adjacent thereto, thereby to pivot shaft 23 and swing bar-type guide 24 to the oblique position also shown in broken line.

Solenoid 39 is selectively energized when it is desired to divert a sheet of film away from drier 2 and out of the processor into catch tray 36. Since only selected sheets of film are moved into this alternate transport path, however, solenoid 39 should be energized, and guide element 24 should be pivoted upwardly, only when such a selected sheet is approaching guide element 24. In order to accomplish this operation, each of said selected sheets of film is tagged" by an indicium of predetermined character; and a sensor system responsive to said indicium is positioned immediately adjacent to and upstream of the guide element 24 to energize solenoid 39 when such an indicium is detected. This aspect of the invention will now be discussed in further detail.

As shown in FIG. 3, a sheet of film 41 which needs no drying is tagged by the attachment thereto of a leader 42 having a color different from that of the film 41. Leader 42 may be a transparency, and it may be attached to the leading edge of film sheet 41 by means of a strip of pressure sensitive tape 43, before the sheet 41 is fed into the processor. Leader 41 may, for example, be either a red or yellow transparency.

The sensor system which is provided to detect the presence of colored leader 42 comprises a light source housing 25 containing a lamp 26 and a lens 27 positioned below fixed guide element 22 for directing a beam of light upwardly between the bars of said fixed guide element 22 (see FIG. 2). A light sensor 28 is mounted at a position above fixed guide 22, e.g., on the top cover 37 of the processor (see FIG. 1). Light sensor 28 includes a half mirror 29, a further mirror 30 disposed above mirror 29, a red filter 31r disposed in the path of reflected light from mirror 29 between said mirror 29 and a'photoelectric cell 32r, and a blue filter 31b disposed in the path of reflected light from mirror 30 between said mirror 30 and a photoelectric cell 32b. The output of photoelectric cell 32r is connected to the input of a standard signal generator 44 (see FIG. 4) the output of which is in turn coupled to one inout of AND gate 47. The output of photoelectric cell 32b is similarly coupled to the input of a standard signal generator 45, the output of which is inverted by an inverter 46 and thereafter applied to the other input of AND gate 47. The output of gate 47 is coupled to an appropriate amplifier (not shown) and may be used to control a relay (not shown) for selectively energizing solenoid 39.

Let us first assume that no sheet of film is present on fixed guide 22. Under these operating conditions, light from source 25 will be reflected by both

mirrors

29 and 30 through

filters

31r and 31b onto both

photoelectric cells

32r and 32b. The two photoelectric cells are adjusted to generate equal, or balanced, photoelectric currents at their outputs under these operating conditions. The two signal generators 44 and 45 will, accordingly, provide like output signals but, due to the action of inverter 46, only a single input signal of proper polarity will be applied to gate 47. When no film is present on fixed guide 22, therefore, gate 47 will not produce an output and solenoid 39 will not be energized.

When a sheet of black and whilte film is present on fixed guide 22, the same operation will occur. Those portions of the sheet which are comparatively transparent to light will cause the system to operate in the fashion already described. Those portions of the film which are comparatively opaque will block light from light source 25 and will, accordingly, cause the photoelectric currents of both

cells

32r and 32b to cease, thereby producing an identical end result. Thus, solenoid 39 will remain in its de-energized state when no sheet of film is present on guide 22, or when a sheet of conventional black and whilte film is transported onto said guide 22.

Let us now assume, however, that the sheet of film being transported through the system takes the form shown in FIG. 3. When the colored leader 42 passes onto fixed guide 22 the red light (or yellow light, as the.

case may be) which is now directed from said leader onto

mirrors

29 and 30 will penetrate the red filter 3lr just as well as white light, but said colored light cannot penetrate blue filter 31b. As a result only photoelectric cell 32r will produce an output, while the output from cell 32b will cease. Under this condition of operation, the signal output from cell 32r will cause signal genera tor 44 to apply a signal to one input of gate 47, and the absence of an output from cell 32b will cause inverter 46 to apply a signal to the other input of gate 47. Under this condition of operation i.e., when only one of the two photoelectric cells has an output, the gate 47 will produce an output signal which, in the fashion already described, can be used to energize solenoid 39. As a result, when colored leader 42 is transported onto fixed guide 22, movable guide 24 will be immediately redirected to its oblique position so as to transport leader 42 and its attached film sheet 41 upwardly through rollers 33, 34 and into catch tray 36.

The guide 24 returns to its original position, e.g., under the influence of gravity or by means of an added spring, after the output from gate 47 ceases. The length of the leader should be so selected that the leading edge of leader 42 will reach the nip of drive rollers 33, 34 by this time. The films being processed in normal fashion must have a length sufficient to bridge the gap between rollers l5, l6 and 17, 18. Similarly, when a sheet of film is associated with a colored leader for the purposes stated, the resultant composite film sheet must have a sufficient length to bridge the gas between

rollers

15, 16 and 33, 34.

The leader must, of course, be attached manually before the selected sheet of film 41 is fed into the processor. This requisite preliminary task can, however, be accomplished with little difficulty, and the advantages which are achieved by use of the invention more than compensate for the time required to prepare the selected film sheet.

While I have thus described a preferred embodiment of the present invention, many variations will be apparent to those skilled in the art. The foregoing description is accordingly intended 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 my invention, 1 claim:

1. An automatic film processor comprising a plurality of film treatment stations, transport means for normally transporting sheets of film to be processed along a predetermined path between and through said stations thereby to effect processing of each of said film sheets in a predetermined sequence of steps, said transport means including switchable means for selectively altering said transport path, and control means responsive to an indicium of predetermined character on a selected sheet of the film being processed for operating said switchable means to alter the transport path for said selected sheet of film thereby to vary the sequence of processing steps for said selected sheet of film.

2. The processor of claim 1 wherein one of said treatment stations comprises a drier, said switchable means being located adjacent the entry of said drier for diverting said selected sheet of film away from said drier.

3. The processor of claim 2 wherein said switchable means includes a first pair of superposed drive rollers disposed adjacent the entry of said drier, a second pair of superposed drive rollers disposed adjacent a catch tray, a movable guide element upstream of both of said pairs of rollers and normally positioned in line with the nip of said first pair of rollers, said guide element being mounted for movement to a position in line with the nip of said second pair of rollers, and operator means responsive to said indicium of predetermined character for selectively moving said guide element to direct said selected sheet of film into said catch tray via said second pair of rollers instead of into said drier via said first pair of rollers.

4. The processor of claim 3 wherein said indicium of predetermined character comprises a distinctively colored leader attached to said selected sheet of film, said control means comprising color sensing means for selectively generating a control signal in response to the presence of said colored leader, said operator means comprising a solenoid connected to said movable guide element, and means responsive to the generation of said control signal for energizing said solenoid to move said guide element.

5. The processor of claim 4 wherein said guide element is mounted for'pivotal movement.

6. The processor of claim 1 wherein said switchable means comprises a movable guide element normally disposed in line with said predetermined path, said control means being operable to move said guide element away from said predetermined path thereby to divert said selected sheet of film into an alternative transport path.

7. The processor of claim 6 wherein said indicium of predetermined character comprises a distinctive leader attached to said selected sheet of film.

8. The processor of claim 7 wherein said leader has a distinctive color, said control means including color sensing means disposed adjacent the upstream end of said movable guide element.

9. The processor of claim 8 wherein said distinctively colored leader is transparent to light, said color sensing means comprising a light source on one side of said normal transport path, color filter means disposed on the other side of said normal transport path, and photoelectric means selectively responsive to light projected thereon from said source via said colored leader and thence via said color filter means for generating a control signal, said control means including solenoid means responsive to said control signal for moving said guide element.

10. The processor of claim 9 wherein said color filter means comprises a pair of differently colored filters, optical means for directing light passing from said source-across said transport path through both of said filters in parallel, said photoelectric means comprising a pair of photoelectric sensors disposed adjacent said pair of filters respectively and responsive to light passing through said filters respectively for producing output signals, and circuit means coupled to the outputs of said pair of sensors for inhibiting the generation of said control signal when both of said sensors produce an output signal and for generating said control signal when only one of said sensors produces an output signateg- Januar 15, 1974 Patent Nog 1 69 Inventofls) Manslalmi M i k If is certified that error appears in the bbve-identified patent and that said Letters Patent are hereby corrected as shown below:

In lthe Heading:

A Iterc [73 change "Log Electronics Inc. to

, LogEtronics Inc.

s gned rid sealed this 30th day of Jul -1971p.

L) .t t,e'st: COY M GIBSON JR. C. MARSHALL DANN testing Officr Commissioner of Patents UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 5,26 d- January 15, 1974 InVent Masami Morioka It is Certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Inflthe Heading:

Iterfi [73] change "Log Electronics Inc. to LogEtro nics Inc.

v I Signed and sealed this 30th day of July 197 AL) Attest: U McCOY M. GIBSON, JR, I c. MIIRSIIALL DANN Attesting Officer Commissioner of Patents

Claims

5. The processor of claim 4 wherein said guide element is mounted for pivotal movement.

10. The processor of claim 9 wherein said color filter means comprises a pair of differently colored filters, optical means for directing light passing from said source across said transport patH through both of said filters in parallel, said photoelectric means comprising a pair of photoelectric sensors disposed adjacent said pair of filters respectively and responsive to light passing through said filters respectively for producing output signals, and circuit means coupled to the outputs of said pair of sensors for inhibiting the generation of said control signal when both of said sensors produce an output signal and for generating said control signal when only one of said sensors produces an output signal.