US3256791A - Electrophotographic process and apparatus for the automatic and continuous reproduction of originals - Google Patents

Description

E. BLUME ET AL ELECTROPHOTOGRAPHIC PROCESS AND APPARATUS FOR THE AUTOMATIC AND CONTINUOUS REPRODUCTION OF ORIGINALS 5 Sheets-Sheet 1 xEEwu R INVENTOR.S ERICH Bl UM E KURT Jns 6 ATTORN EY June 21, 1966 Filed April 29, 1963 FIG.3

June 21, 1966 E. BLUME EI'AL 3,256,791

ELEGTROPHOTOGRAPHIC PROCESS AND APPARATUS FORTHE AUTOMATIC AND CONTINUOUS REPRODUCTION OF ORIGINALS Filed April 29, 1963 5 Sheets-Sheet 2 Q E k 25 -35 a N I 5 w R m 2 3* Q g m Q; Hg Q Q2: m Q Q Q k g \x I\ Q w fi- 9 i JNVENTORS ERICH B UME KURT J N S BY ATTORN Y June 21, 1966 E. BLUME ETAI. 3,256,791

ELECTROPHOTQGRAPHIC PROCESS AND APPARATUS FOR THE AUTOMATIC AND CONTINUOUS REPRODUCTION OF ORIGINALS Filed April 29, 1965 5 Sheets-Sheet 5 FIG. 4

INVENTORS E RICH a u M E KURT J NS June 21, 1966 E. BLUME ETAL 3,256,791 ELEGTROPHOTOGRAPHIC PROCESS AND APPARATUS FOR THE AUTOMATIC AND CONTINUOUS REPRODUCTION OF ORIGINALS Filed April 29. 1963 5 Sheets-Sheet 4 FIG. 5

Exposure INVENTORS ERICH BLUME KURT JONS 5/3 ATTORN Y June 21, 1966 E. BLUME ETA]. 3,256,791

ELECTROPHOTOGRAPHIC PROCESS AND APPARATUS FOR THE AUTOMATIC AND CONTINUOUS REPRODUCTION OF ORIGINALS Filed April 29, 1963 5 Sheets-Sheet 5 Film San Card\ F 6 1NVENTOR.S ERICH Bl,UME KURT JONS BY 3W, 2.

ATTOR Y United States Patent 3 256,791 ELECTROPHOTOGRAlHlC PROCESS AND APPA- RATUS FOR THE AUTQMATIC AND CONTINU- OUS REPRQDUCTKON F URIGINALS Erich Blame and Kurt .liins, Wiesbaden-Biebrich, Germany, assignors, by mesne assignments, to Azoplate Corporation, Mnrray'I-Iill, NJ.

Filed Apr. 29, 1963, Ser. No. 277,415 Claims priority, application Germany, Nov. 2, 1962,

9 Claims. (Cl. 95 1.7)

The present invention relates to an electrophotographic process by which copies preferably up to size DIN A3 (297 x 420 mm.) can be made automatically and continuously, with the aid of director cards, preferably from film negatives which have been inserted into a film sort card. Further, the present invention includes an apparatus for performing the process.

Processes and apparatuses are known, which are useful for continuous reproduction employing a web-like electrophotographic materialvwhich is exposed by contact exposure or by episcopic or diascopic projection. In these processes, it is, however, necessary to feed the originals separately into the apparatus before the reproduction process is started, whereupon the electrophotographic charging, exposing, developing and fixing operations automatically proceed in sequence. In the case that more than one copy is required from one and the same original, it is necessary to start the reproduction process for each copy by selection and insertion of the original by hand.

Further, it is known to stack, in a magazine, film negatives inserted into film sort cards, and to cause a reproduction apparatus to take the single negatives from this magazine. In this case, however, it is also necessary for the number of copies to be made from a single negative to be set by hand with a pre-selection switch.

In order to save time and effort, however, there is a great need in the art to have successive reproduction operations, in particular from film negatives such as are used for documentation purposes, follow each other as rapidly as possible and completely automatically, above all'in regard to the production of plural copies. Moreover, it is important in this automatic operation that copies of the highest possible quality be produced from negatives hav ing different density values. These manifold and complicated demands are not met by the processes and apparatuses hitherto known, because they do not meet the requirements with regard to equipment, freedom from flaws, precision, and construction.

The present invention provides an electrophotographic process for the automatic and continuous. production of reproductions, preferably of sizes up to DIN A3, from positive or negative transparent masters. In this process, the transparent originals are inserted into so-called film sort cards which may be provided with recording marks, and stacked, alternately with director cards which carry the desired reproduction directions coded accordingly to the punched-card principle, in an introductory section from which they consecutively and automatically are passed to the scanning system and the optical section of the apparatus where the specific impulses of each director card are stored by an electrical system and transmitted, in the optical section, to the respective film sort card, whereupon, in the optical section, the original is irradiated, the image plane is swivelled by 90 and the path of rays is further bent by 90 by means of an optical system of prisms. The optimum time of exposure is measured by a light dosage device, the image being projected on the previously charged electrophotographic material and image-wise discharging it, while the paper web is simultaneously arrested at the projection plane by an intermittently operative transport mechanism, and the material is again continuously conveyed and subsequently developed, fixed, and cut into desired sizes.

The following is a more detailed description of the invention:

First, the transparent original must possess a suitable shape in order to be processed in the apparatus of the present invention. In the case of film negatives, which are preferably used in connection with the present invention, this is effected by inserting or cementing them into punched cards having a window corresponding in size to the negatives,-i.e. so-called film sort cards. FIG. 6 shows such a film sort card to scale, which may be used in the present invention. Suitable negatives for this special kind of film sort card are unperforated films of size 32 x 45 mm. or perforated films of size 24 x 36 mm. Unperforated films are particularly suitable. However, the process of the present invention is not limited to the use of these standard film negatives, but other transparent originals preferably approximating the above-mentioned sizes, may also be reproduced.- It is immaterial whether. the originals are given an optimum degree of exposure or not, provided they can be reproduced at all. If the masters usedare photoprints from originals, they may be positives or negatives. As explained in further detail below, it is possible in each case to produce an image corresponding to the original, i.e. a positive, byselection of a suitable toner, viz. a positive-working toner or a reversal toner.

The above mentioned film sort card, which carries the original, is placed into a storage magazine. Below this film sort card, there is placed the so-called director card which coacts with it. This director card has the same size and is provided wit-h imprints which enable it to be marked in known maner by punching. Using a pre-determined code, these marks are so made that the scanning device referred to below can convert them into corresponding impulses. This director card thus serves the purpose of pre-determining the number of copies to be made from an original.

Thus it is possible, for example, by using a director card with'two decades, to produce up to 99 copies. If

more than 99 copies are required from one original, a director card may be used having e.g. a division of three decades, so that up to 999 copies can be'made.

In the manner stated above, the originals to be reproduced, with their specific director cards, are stacked one above the other in the storage magazine. ber of cards, up to about 600, may be stacked in this manner. The cards are then removed one by one from the above-mentioned magazine with the aid of a knifelike withdrawal device, the so-called card-knife, i.e. in each case the director card is first removed and then moved on via a contact scanning device which scans the card for punched marks. The directions taken from the card are stored in known manner by the electrical system, while the director cards themselves are ejected and gathered in a collecting basket, without releasing the optical,

system at this stage of operation.

The film sort card appertaining to this director card is withdrawn by the above-mentioned card-knife and conveyed to the optical section of the apparatus by means of a mechanically driven roller system. In the optical section, the movement of the card is stopped at a position exactly beneath the irradiation device. At this stage of the operation, irradiation is effected. For this purpose, a point-shaped light source-preferably a high pressure mercury vapor-lar'np-is reflected via a condenser system in the lens. Between the lens and the condenser system, there is placed the original the image plane of which is swivelled in known manner by while the image-Wise differentiated path of rays is deflected by 90 by means A large numarrested during exposure thereof.

of an optical system of prisms. This affords great advantages since, as shown below, it results in the production of an image which covers the whole width of the web of electrophotographic material illuminated by the path of rays and thus full utilization of the web in the case a format of size DIN A4 is used, without the necessity of turning the original, which in the most frequently occurring case is a film negative of size 32 x 45 mm., such as are customarily used for documentation purposes. The original is inserted in a film sort card with its longer side parallel to the longitudinal edge of the film sort card. If an enlargement of size DIN A3 is desired, the path of rays is deflected only by 90 in the optical system of 'prisms, while size and sharpness of the image are determined by adjustment of the lens and of the plane of the latent image.

To avoid heating and, thereby, damaging of the negatives, the path of rays of the above mentioned points'haped light source is passed over a so-called cold-light mirror which transmits the infra-red rays and reflects only the rays of the visible and the ultra-violet ranges which are desired in the illumination.

In order to obtain'the exact time of exposure, a socalled light dosage device is provided. This device measures the reflected or incident light at the edges of the projected image, i.e. in the darkest areas of the image, and thus supplies to the optical system the values indicating the range of exposure. When an optimum light quantity is attained, the light dosage device interrupts the exposure, thus ending the illumination of the electrostatically charged photosemiconductor coating of the elecrophotographic material to be described in further detail below.

By a further operation, which follows automatically, the original is passed on to a collector basket. Alternatively, if the orders on the director card require repetition of the reproduction operation, the above described operation is repeated as desired, using the same original which, in this case, is not further conveyed.

There follows the next director card with the next film sort card, which are similarly handled. The operation is repeated until the card magazine is empty. The sequence of operations is as rapid as possible and is limited only by the ability of the card and the original to withstand mechanical stress.

Prior to each exposure, the electrophotographic material differentiated during the preceding illumination step is further conveyed, so that the electrostatically charged photoconductor material is always ready for exposure.

Prior to exposure, the electrophotographic material referred to above is provided, in known manner, with an electrostatic charge from a charging device. The material comprises a web-like strip. After termination of the exposure as described above, followed by the production of the latent electrostatic image, the electrophotographic material is conveyed, at a constant speed, to the succeeding stations of operation, while that portion of the material which follows it in the direction of feed is This is effected by means of a loop which is successively formed and taken up.

The material bearing the latent image now passes the developing station where it is contacted, in known manner, with a developer mixture applied by a magnetic brush. Duringthis operation, a bias voltage may be applied. The toners used may have the same polarity as the areas not struck by light, or they may be oppositely charged. Accordingly, a reversed image or an image corresponding to the charged areas will be obtained.

In the'following station, the latent image thus made visible is subjected to a heat treatment by means of an infra-red radiator in which heat from a filament is reflected on the surface of the electrophotographic paper from an elliptical reflector surrounding the radiator. While the thus fixed image is further conveyed, two conltrol marks facilitate the cutting thereof into single formats. The finished copy drops into a basket from which it can be removed.

The present invention includes an apparatus for performing the above process, the apparatus generally comprising a card magazine for receiving the film sort cards and the director cards, a Withdrawal and transport device for one card at a time, a contact roll, a scanning brush, an optical system for irradiation, provided with a coldlight mirror, a system of prisms for swivelling and defiection of the image plane, a light dosage device, an exposure device which causes the formation of additional control marks, a projection plane which is situated in the path of rays differentiated by the original, a removable roll mounted beneath the plane and adapted to receive the web-like electrophotographic material, a charging device adjacent the roll, a discontinuously driven drive roll which follows the plane in the direction of feed, a further continuously driven roll, an oscillating roller between the rolls which compensates the discontinuity, a developing device following the driven roll in the direction of feed, a fixing station, a cutting device controlled by the abovementioned control marks, a collector basket and, further, a light-tight housing surrounding the entire mechanism, which also contains all the electrical equipment and the mechanical drive.

The apparatus and process for performing the present invention are further illustrated in the accompanying drawings in which:

FIG. 1 is a schematic view in longitudinal cross-section of the introductory part of the apparatus.

FIG. 2 is a schematic sectional side view in elevation of the optical system.

FIG. 3a is a schematic front view of the system of prisms.

FIG. 3b is another view of the system of prisms in a different position.

FIG. 4 is a longitudinal cross section of the paper feed and of the apparatus for performing the process.

FIG. 5 is a schematic view in longitudinal cross section of the drive.

FIG. 6 is a plan view of a film sort card to scale, and

FIG. 7 is a plan view of a director card.

In the card magazine 311 shown in FIG. 1, which holds a large number, viz. up to about 600, of film sort cards and director cards, the director cards and film sort cards are stacked above each other, the director card which controls the negative being placed beneath the respective film sort card. If one director card shall be applied to several film sort cards, all these film sort cards are arranged above this director card. The dimensions of the card magazine should preferably be adapted to the size of the cards used, advantageously the card sizes shown in FIGS. 6 and 7. However, it is also possible to use cards with different measurements in the apparatus.

The director card is picked up in known manner with the card knife 3 and passed to the first pair of transport rolls 6 and 7 via a rack and pinion, over a crank gear and through the roll 4 and disc-shaped knife 5. In the scanning station, which comprises the contact roll 8 and the scanning brush 9, the director card is scanned and the impulse indicating the number of copies to be made is stored in known manner by means of an electrical system. Subsequently, the director card is ejected via the optical system, without actuating further operations. This is effected as follows: A photoelectrical resistance provided with a transmitter lamp 10 is arranged in such a manner that it is switched on by the edge of the director card before the first row of punches therein reaches the scanning brush 9 and the contact roll 8, and thus closes the circuit of the scanning station. The second photoelectric resistance is not switched on until the director card has passed the pairs of rolls 12/13 and 14/ 15, the actuation of the second resistance being effected by means of a time delay member. Subsequently, the director card reaches the collecting basket 16. Then,- the above-mentioned devices, i.e. card-knife 3, rolland disc-shaped knife 5 become again operative and draw the next film sort card from the stack in the magazine. This film sort card passes on to the exposure zone and with its edge switches off the drive motor 17, via thephotoelectrical resistance 11 and by means of magnetic coupling. The stored data, received from the director card, is released and causes the lens shutter to be opened for the desired time of exposure. This operation is repeated for as many times as required by the stored information. Subsequently, the film sort card is also conveyed to the collecting basket 16.

FIG. 2 shows the optical system of the apparatus. This optical system may be subdivided into the light optic parts and devices which serve to retransmit the incident rays.

The light optic part consists of the light source 18, e.g. a high pressure mercury vapor radiator having a very small focal spot, the cold-light mirror 19, the condenser system 20, the lens shutter 21, and the lens 22. The cold-light mirror insures that the thermal stress exerted on the film is maintained as small as possible, since it transmits infrared rays and reflects for the'desired illumination only the visible rays which are essential for the image formation.

Mirrors of this kind are described, e.g. in a publication-of the Jenaer Glaswerke Schott & Gen., Mainz, Germany. A cooling blower 23 provides sufiicient cooling of the lamp and the cold-light mirror. The optical raypath proceeds from the negative 24 via the shutter and the lens to the system of prisms, as shown in FIG. 3. This system of prisms, which transmits the ray path, is pivotable by 90 and mounted on the prism holder 26 by means of a pin 25. A

In the case of a projection of DIN A3 size, the ray path proceeds via the triangular prism 27 to the projection plane 28. The negative which, when viewed from above, is readable, is thus projected as a readable image of oblong size onto the projection plane.

In case a projection of size DIN A4 (210 x 297 mm.)

is required, a swivelling of the image by 90 will be necessary, because it must be reproduced at right angles to the paper web (half-sheet size). This swivelling of the image is effected by means of a half cube 29 and a surface mirror 30, the position of the negative being unchanged.

The displacement of the lens 22 caused thereby is compensated for by a shifting of the introductory part of the apparatus. Size and sharpness of the image are adjusted by shifting the projection plane and thelens by means of adjusted stop locations.

FIGS. 4 and 5 are schematic drawings of the paper feed, with drive, the paper cutting device, and other technical details.

From the supply roll 32 the paper webpasses first over a charging device-which, as shown in the present case, may be a plurality of corona wires 33and from there to the projection plane 28 and the transport roll 34. The transport of the paper is effected as follows:

The drive motor 35 drives the sliding pin drive 37 by means of an intermediate gear 36. The chain 40 is reciprocated over a connecting rod 38 attached to a sliding member 39. A sprocket wheel 41 which is moved to the right and to the left, with the reciprocating chain 40, moves the transport roll 34 to the left only, by way of freewheeling. This causes the paper web to move discontinuously over the projection plane 28. Since the movement of the paper web is sine-shaped due to the crank gear, no self-motivating spin of the roll 32 is caused.

Over the oscillating roll 42 the paper web is passed to the triple rolls 43 which are driven overan intermediate wheel 44. From here, the paper web passes continuously over the guide rolls 45 and 46 and the twin rolls 47 with the spooling motor flanged thereto. Between the two kinds of movementcontinuous and discontinuous-a loop is formed in the paper web which is drawn 0E during exposure. For technical reasons, a continuous movement of the paper web is necessary during development and inoperative.

fixation, as well as for operation of the cutting device 50.

Development may preferably be effected by means of an arrangement of magnetic rolls, with a revolving wheel 48 attached thereto. Particularly good results are obtained by roll application according to copending application Ser. No. 247,025, filed Dec. 26, 1962 and to Belgian Patent No. 626,526, filed Dec. 24, 1962.

For fixation by means of the fixing device 49, a quartz burner is advantageously used which is surrounded with a radiation reflecting surface of such shape that the total of the infra-red radiation is concentrated on the surface of the paper.

As a protection against re-heating, a protective shield is thrust into the ray path when the infra-red source is During operation of the infra-red source, this protective shield is removed from the ray path by means of a current-carrying electromagnet. When the current is interrupted, the shield drops automatically into the ray path between the infrared source and the electrophotographic material.

In the cutting device 50, a transport roll 51 is driven by I the triple rolls 43 through a chain drive; a pressure roll 52, which is biased by a lifting magnet, effects intermittent transport of the paper during the cutting operation. Cutting of the paper is effected by a fixed lower knife 53 in cooperation with a movable knife 54. A mark, produced by contact exposure in the projection plane 28, is scanned by reflex gauging using a photoelectrical resistance 56 and actuates the cutting operation. Subsequently, the enlargement of size DIN A3 or DIN A4 is ejected and drops into the collecting basket 58. An exact chronological sequence of these operations is repeated on additional material.

The Width of the web of electrophotographic material is such that sizes DIN A3 and DIN A4 can be reproduced, DIN A3 longitudinally of the web of paper and DIN A4 transversely. The roll has a fairly large capacity Paper rolls up to 300 In. or more may be used. These rolls can be easily exchanged, i.e. the end of the preceding paper web may be attached in a simple manner to the beginning of a new paper web, so that a continuous operation is possible and it is unnecessary to thread the new paper web in the machine.

The entire apparatus is enclosed in a light-tight housing. For better accessibiilty, each of the side walls is provided with a door so that the inner construction can be reached. The side walls referred to are provided with openings which serve for an easy first insertion of the electrophotographic paper. These openings are covered by light filter plates during operation of the apparatus as well as in the inoperative condition, which permit observation of the inner operations. Thus the reproduction process cannot be disturbed when the doors are opened during operation.

Further, such parts as the corona device, developing device, and fixing device, may be removed separately so that in the case of breakdowns of these high-duty parts, they can be quickly exchanged. Moreover, in the case of trouble in the electrical system, the single circuit elements may be removed and exchanged, since they are mounted in blocks according to the drawer system.

The process and apparatus according to the present invention permit the automatic and continuous reproduction of originals. In a particularly favorable manner, varying numbers of copies can be produced from each original used. Above all, it is of advantage that the use of a cold-light mirror andthe mechanical conveying system, the negatives are handled with care.

In addition, the process according to the present invention and the apparatus connected therewith permit a very rapid operation, because no time is lost by watching the operation and interfering with it by hand. For example, in the present case, 600 copies of size DIN A4 may be made in less than 40 minutes. Further, it is possible to process more than one filling of the card magazine with the paper supply available in the apparatus. Optimum utilization of the web-like electrophotographic material is possible by adapting the image axis to the required format.

A discontinuous operation is also possible with the apparatus according to the present invention. Devices such as the above-mentioned protective shield in front of the infra-red radiator or an interruptor switch for the paper web prevent the electrophotographic material and the entire apparatus from being damaged by inadvertent use, in particular when the apparatus comes to a sudden halt, either voluntarily or involuntarily. Moreover, all parts which are subjected to increased stress, such as the charging device, developing station, fixing device, cutting apparatus and electrical elements, can be easily exchanged as a whole so that, in the case of unexpected events, these parts may be easily exchanged and operation immediately resumed. Thus, by using the present invention for professional purposes, a continuous excution of incoming orders is possible with a minimum of labor.

What is claimed is:

1. An apparatus for the automatic and continuous preparations of reproductions comprising a card magazine for film sort cards and director cards, means for passing the cards to a scanning means, means for passing the cards to an optical system, the latter including irradiation means, a projection plane in the path of the rays from the irradiation means, means for passing a continuous web of an electrostatically charged electrophotographic material through the projection plane with an intermittent motion, and means for continuously moving the electrophotographic material having an electrostatic image thereon past a developing station and a fixing station, the apparatus being enclosed in a light-tight housing.

2. An apparatus according to claim 1 in which the optical system includes prism means for deflecting the rays from the irradiation means.

3. An apparatus according to claim 1 in which the optical system includes a light dosage means.

4. An apparatus according to claim 1 including means for cutting the electrophotographic material.

5. A process for the automatic and continuous preparation of reproduction which comprises withdrawing film sort cards, containing originals, and director cards from a storage zone, passing the cards successively to a scanning zone and an irradiation zone, projecting a light image of the original on a continuous web of an electrostatically charged electrophotographic material moving through the irradiation zone with an intermittent motion, and continuously moving the web having an electrostatic image thereon past a developing station and a fixing station.

6. A process according to claim 5 in which the rays in the irradiation zone are deflected onto the electrophotographic material.

7. A process according to claim 5 in which the time of exposure in the irradiation Zone is automatically controlled.

S. A process according to claim 5 in which the original is irradiated with light in the visible and ultra-violet ranges only.

9. A process according to claim 5 in which the electrophotographic material is cut to a desired size after fixing the image thereon.

References Cited by the Examiner UNITED STATES PATENTS 2,297,691 10/1942 Carlson -1.7 X 2,741,960 4/1956 Oldenboom 95l.7 2,791,949 5/1957 Simmons et a1 951.7 2,956,487 10/ 1960 Giaimo 951.7 3,002,434 10/ 1961 Reuter 95-1.7 3,032,009 5/1962 Magnusson 95-1.7 X 3,051,568 8/1962 Kaprelian 951.7 3,075,493 1/1963 Cerasani 951.7 X

EVON C. BLUNK, Primary Examiner.

Claims (1)

1. AN APPARATUS FOR THE AUTOMATIC AND CONTINUOUS PREPARATIONS OF REPRODUCTIONS COMPRISING A CARD MAGAZINE FOR FILM SORT CARDS AND DIRECTOR CARDS, MEANS FOR PASSING THE CARDS TO A SCANNING MEANS, MEANS FOR PASSING THE CARDS TO AN OPTICAL SYSTEM, THE LATTER INCLUDING IRRADIATION MEANS, A PROJECTION PLANE IN THE PATH OF THE RAYS FROM THE IRRADIATION MEANS, MEANS FOR PASSING A CONTINUOUS WEB OF AN ELECTROSTATICALLY CHARGED ELECTROPHOTOGRAPHIC MATERIAL THROUGH THE PROJECTION PLANE WITH AN INTERMITTENT MOTION, AND MEANS FOR CONTINUOUSLY MOVING THE ELECTROPHOTOGRAPHIC MATERIAL HAVING AN ELECTROSTATIC IMAGE THEREON PAST A DEVELOPING STATION AND A FIXING STATION, THE APPARATUS BEING ENCLOSED IN A LIGHT-TIGHT HOUSING.

Images