US3690759A

US3690759A - Electronic photocopying machine

Info

Publication number: US3690759A
Application number: US543226A
Authority: US
Inventors: Teizo Kushima; Susumu Tanaka; Masaya Ogawa
Original assignee: Minolta Co Ltd
Current assignee: Minolta Co Ltd
Priority date: 1966-04-18
Filing date: 1966-04-18
Publication date: 1972-09-12
Anticipated expiration: 1989-09-12

Abstract

A feeding and conveying arrangement for sheets of xerographic copy paper passing through the recording and developing sections of a photocopying machine. Three feeding mechanisms are provided, one to take sheets from the magazine, a second to take the sheets through the exposure station, this one being on a pivotal assembly, and a third for feeding the sheets through the developing means at a lower velocity than that at which the others operate, means being provided to accommodate a temporary loop of paper until it can be handled by the slower developing feeder.

Description

United States Patent Kushima et al.

1 51 Sept. 12, 1972 [54] ELECTRONIC PHOTOCOPYING MACHINE [72] Inventors: Teizo Kushima, Osaka; Susumu Tanaka, Ditto; Masaya Ogawa, Ditto, all of Japan [73] Assignee: Minolta Camera Kabushiki Kaisha, Osaka, Japan 22 P116115 April 18,1966

[21] Appl. No.: 543,226

[30] Foreign Application Priority Data July 27, 1965 Japan ..40/45427 Aug. 26, 1965 Japan ..40/70l29 July 2, 1965 Japan ..40/5405l Aug. 20, 1965 Japan ..40/50816 Aug. 18, 1965 Japan ..40l67863 Aug. 17, 1965 Japan .....40/50077 July 27, 1965 Japan ..40/45427 Sept. 10, 1965 Japan ..40/74304 [52] US. Cl ..355/10, 95/14 [51] Int. Cl. ..G03g 13/10 [58] Field of Search ..95/l.7, 94, 73, 14; 355/3, 355/10 [56] References Cited UNITED STATES PATENTS 3,245,330 4/ l966 Okishima ..95/ 1.7

Donohue ..1 18/7.

3,348,522 10/1967 1,912,427 6/1933 Bodan ..9s/94 x 2,780,972 2/1957 Fairbanks ..95/14 x 3,309,960 3/1967 Delplanque ..3ss/3 3,397,627 8/1968 Bruning ..3ss/1o 3,416,860 12/1968 Mihojevich ..3ss/10 2,408,310 9/1946 Hassler ..9s/73 3,148,601 9/1964 Trumbull ..9s/1.7 3,272,100 9/1966 Teutsch ..95/1.7 3,282,177 11/1966 Stanton ..9s/1.7 3,318,213 5/1967 Kowalski ..9s/1.7 3,352,218 11/1967 Ostensen ..9s/1.7

Primary Examiner-John M. l-loran Attorney-Anthony A. O'Brien [57] ABSTRACT 1 Claim, 18 Drawing Figures Patented Sept. 12, 1972 6 Sheets-Sheet 1 FIG.|

Patented Sept. 12, 1972 6 Sheets-Sheet 2 Pahnted Sept. 12, 1972 6 Sheets-Sheet 5 FIG.9

FIG. IO

Patented Sept. 12, 1972- 6 Sheets-Sheet 4 I IOB IIO'B 35LMP-4 IIO'A Patented Sept. 12, 1972 I 3,690,759

6 Sheets-Sheet 5 Patented Sept. 12,1972

FIG. I?

6 Sheets-Sheet 5 A ELECTRONIC PHOTOCOPYING MACHINE The present invention relates to a copying machine of the type, wherein zinc oxide powders (ZnO) or equivalent materials are applied to surfaces of papers to produce sensitive papers which can be used by being exposed to rays of light after being negatively electrified, and which are then developed and fixed to complete a copying operation. Particularly, the invention relates to an electronic photocopying machine which is adapted to complete substantially the entire above-mentioned series of steps automatically.

The above-mentioned processes are carried out in an apparatus which comprises a first paper feeding mechanism for feeding the sensitive paper, a second paper feeding mechanism effective from the imparting of sensitivity to said sensitive paper by subjecting the same to negative electrification and ending with the finishing of the exposureand a third paper feeding mechanism to develop and dry theresulting paper.

It has been found that when relatively high paper feeding velocities are desired, the third paper-feeding part of mechanism for the developing and drying is the most objectionable of the three above sections. The reason for this is that wet sheets of paper are generally dried with radiation heat from a lamp or the like and an insufficient drying can occur when the velocity is raised. Moreover, in the development stage, uneveness of toner being applied will take place. It has been ascertained that an appropriate velocity limit is 25 mm/sec, when a lamp of 500 to 750 W is used. However, if the three above-mentioned feeding mechanisms are intended to operate at an equal velocity, the feeding velocity in all will be limited to 25 mm/sec.

It is an object of the present invention to provide an electronic photocopying machine, wherein the copying capacity is improved to shorten photographing time and increase the number of sheets photographed per minute by selecting different appropriate velocity ranges for the different feeding mechanisms in order to meet with the extension and contraction of paper which occurs.

Another object of the present invention is to provide an electronic photocopying machine, provided with two lenses, i.e., one for enlarging and the other for reduction purposes, wherein the distance between the sensitive paper and manuscripts (or originals) is held constant and lenses of different focal distances are used with said distance kept constant for both purposes. In this case, the number of lenses used is not limited to two, but three lenses may well be used. Moreover, the distance between the original and sensitive paper may be changed with use of one lens. The means therefor lies in that the positions of glass plates and lens are selected respectively for enlarging and reduction purposes and the respective photographing is effected at both selected positions.

Another object of the present invention is to provide an electronic photocopying machine equipped with an sensitive paper feeding device for feeding sheets of sensitive paper firmly to the first paper feeding mechanism, wherein sheets of sensitive paper cut into standard sizes are piled atop the machine body, the light photosensitive surface of each said sheet of sensitive paper being held downwards. Moreover, those sensitive sheets of paper are fed from the top portion by the rotation of rollers, suitably driven through a motor, reduction gear or the like. In this case, when both sides of piled-up sheets of sensitive paper are clipped loosely with high frictional material, for instance, such as rubber, sponge or the like, the sheets of sensitive paper can be fed exactly one by one.

A further object of the present invention is to provide an electronic photocopying machine provided with a sensitive paper feeding belt wherein an endless belt has a number of flexible sucking discs. Generally, in a copying machine, wherein an original is projected through lenses, the sensitive paper is fed to photographing positions and stopped there for exposure and again transported to the next developing step after the exposure is completed. However, since, in usual feeding devices, the sensitive paper is clipped between fingers or frame, or sucked to and conveyed on a belt, the former disadvantage only shows shadows of hooks or frames, while the latter is costly and requires a complicated construction. According to the above-mentioned belt conveyor for feeding sensitive paper, such disadvantages can be entirely eliminated.

A further object of the present invention is to provide an electronic photocopying machine, wherein, referring to a copying machine of the type in which objects are projected onto a sheet of sensitive paper through a lens system while the sensitive paper is stationary the distance between sheets of sensitive paper is shortened to improve the copying velocity.

In general, in automatic copying machines, the sensitive paper is usually transported through each step at a constant velocity excepting for the stationary period for the exposure. For instance, in electronic photocopying machines, the sensitive paper is fed successively through the sensitive paper feeding step, electrification, exposure and drying steps at a constant speed. Thus, when a plurality of copies is to be obtained continuously from the same object, each time the sensitive paper is stopped for exposure, the distance between the sensitive paper and that already advanced is extended and the copying velocity per minute will be decreased. Moreover, in the stages of electrification, developing, drying and the like, rather uniform transporting velocity is required otherwise these would result unevenness in the electrification, development, drying and such and quality would be damaged. As for the developing and drying stages, the feeding velocity for the sensitive paper can not be increased at random. Since the two stages are the slowest in an ordinary automatic copying machine, an improvement can be accomplished by looping out of the regular passage between the exposure stage and development stage after exposure and by combining said slow velocity stage and said stopping stage during exposure.

A further object of the present invention is to provide an improved paper feeding device and an accompanying electrification device, in connection with socalled full-frame-projection type (F.F.P) electronic photocopying machine, wherein sensitive paper is stopped for photographing in order to take positivepositive pictures. In general, the feeding is performed by a belt or frictional roller but, according to the present invention, when rollers are used on the side of the sensitized film surface, shadows of the rollers can be avoided on the sensitized film surface in the course of projection as will be shown.

A further object of the present invention is to provide a device for feeding as well as exposing a photosensitive body, wherein the sensitive paper is moved by a transparent belt.

Generally, in a copying machine of the type of projecting through lenses, a device, wherein original and sensitive papers are stopped simultaneously for photographing, during projection, can produce the best images or figures In known devices which do this, there are disadvantages including that shadows of clips or rollers are uselessly photographed, and that no copying is possible at certain portions which are covered by belts and picture surface frames. Furthermore, although the sensitive paper must be held in a plane, it has been found difficult to do this.

According to the present invention, belt conveyors are arranged on both surfaces of the sensitive paper, an optically transparent stop and the images of the originals are projected through the transparent belt.

A further object of the present invention is to provide a low-price paper feeding device of high quality for an electronic photocopying machine.

It is another object of the present invention to utilize the well-known electrostatic attraction such that a sensitive paper and an isolating flexible sheet are passed through an electrification apparatus, both sheets being attracted by electrostatic attraction and introduced to a predetermined position on belt which is stopped for an exposure and driven again so as to transfer the exposed sensitive paper to the next step.

As materials for the above-mentioned belt, materials having a specific resistance of at least approximately l0' -l0bl6 Q/cm, such as nylon, vinyl, polyethylene,

polycarbonate or other general commercial plastic sheet may be used. The sheets of sensitive paper may be such as diazo or silver salt or the like or zinc oxide sensitive paper for electronic photocopying machines. Nearly all types of sensitive paper can be used. Moreover, for an electrification device, a corona electrification device may be used satisfactorily. In the present invention, it is easy to maintain the electrostatic attraction of the insulating belt and sensitive paper for several minutes under a wide range of weather conditions. Moreover, the flatness of the sensitive paper is also very good and the power of electrostatic attraction is so high that if the voltage of an electric source ranges from approximately 4,000 to 5,000 volts, the sensitive paper will not slip or drop off. The adhesiveness by suction, in a perpendicular position or even when the paper is fed with one surface of the paper looking downwards, is exceedingly exact. Moreover, since the quality of pictures is not damaged by the introduction of electrostatic charge, the present device can be utilized for general copying devices and there are many other advantages; and in particular, in the electronic Finally, another object of the present invention is to provide an improved machine of the type wherein sensitized papers cut into final finished sizes are fed to exposure position and are stopped, said machine being provided with an exposure device of simple construction and capable of using any suitable size of sensitive paper and simultaneously capable of forming a full size figure on the whole surface of the sensitive paper, the said device including a feeding roller adapted to shunt or loop outside an optical passage by means of a solenoid operating through a lever.

The present invention is next described in connection with the accompanying drawings, in which:

FIG. 1 is a perspective view of an electronic photocopying machine according to the present invention;

FIG. 2 is a side sectional view illustrating the essential parts of said electronic photocopying machine of the present invention;

FIG. 3 is a side sectional view of a lens exchange device for said electronic photocopying machine;

FIG. 4 is an oblique view of a sensitive paper feeding device;

FIG. 5 is a partial plan of a belt for a sensitive paper feeding belt;

FIG. 6 is a side sectional view thereof;

FIG. 7 is a side sectional view of said sensitive paper feeding device;

FIG. 8 is an oblique view of a sensitive paper separating hook;

FIG. 9 is a diagram showing the displacement of focal distance due to the movement of lenses;

FIG. 10 is a partial perspective view showing a practical example of FIG. 9;

FIG. 11 is an exploded fragmentary view in perspective of a stopping device for lens fixtures;

FIG. 12 is a diagram of an electric circuit for driving and controlling the electronic photocopying machine according to FIGS. 1 and 2;

FIG. 13 and FIG. 14 are respectively an electric circuit diagram and perspective view of a dial counter for sheet numbers of sensitive paper;

FIG. 15 is a partial perspective view of an electrification device and an exposure frame in said electronic photocopying machine;

FIG. 16 is a fragmentary and exploded perspective view showing a roller-supporting position; 7

FIG. 17 is a perspective view of said exposure frame and of an exposure frame body accompanied with driving rollers;

FIG. 18 is an explanatory sectional view of an intermittent sensitive paper feeding device for said electronic photocopying machine; and

FIG. 19 illustrates a controling device for concentrations of developing solution.

To begin with, in FIGS. 1 and 2 representing a general construction of the electronic photocopying machine of the present invention, 1 denotes an outer casing and 2 denotes a glass plate on which an original 3 is loaded; 4 denotes a soft plate to push down said original; 5 and 6 denote illuminating lamps for the original; 7 is an illuminating box with a coiling fan for illuminating the surface of the original with the aid of the lamps; 8 is a reflecting plate to reflect the image from the original; 9 denotes a projecting lens means; 10 denotes a transparent focusing glass for making the sensitive paper 20 even. A clearance of approximately 1 mm is provided between said transparent focusing glass and plane rear plate '10, and said sensitive paper is fed into said clearance.

Two projecting lenses 9, 1' are used as shown in FIG. 3, of which, for instance, lens 9 is a projecting lens for equi-multiple photographing and lens 9' is a projecting lens for contraction photographing. In this case, the equimultiple and contraction photographings are performed by various lenses, mentioned above, of varying focal lengths. As illustrated in FIG. 3 and 11, a lens fitting 19 is provided with a knob 13 which protrudes outside the machine through a hole 14 formed in the outercasing and a lever shank is provided on a pin 11, as lens-exchanging means. Furthermore, a stopping mechanism (see FIG. 11) comprising a ball 16, a spring 17 and a pushing screw 18 is provided on a front panel 12 of a photographing box 15. When either of the two lens comes to the optical axis, the ball 16 enters a recess 38 of the lens fitting member 19, said fitting member being thereby stopped. In such a way, with even two or three lenses, similar operation can be conducted. Further as in said embodiment of the present invention, the distance between the original 3 and sensitive paper 20 may be changed. The means therefor are shown in FIG. 9, wherein the glass plate 2 on which the original is loaded and the lens 9 are placed respectively at the position shown by solid lines for the equimultiple photographing and the contraction photographing is performed by displacing said glass plate 2 and said lens 9 to the dotted line positions. This is easily understood from the fundamental calculation regarding the optical system, and the carrying out means is shown in FIG. 10.

Namely, in FIG. 10, a frame 2 joined with the circumference of glass plate 2 for loading the original 3 is formed with a plurality of holes H,H Each middle holes H, engages a pine P, provided in the outer casing l of the copying machine proper, for purpose of positioning, while the other pairs of holes H and H are spaced respectively by distances A and B to engage P and P on the outer casing 1. If the frame 2 is taken off the pins and turned around through l80 horizontally, and then if the frame is engaged with the pins again, pin P, is sufficiently long to fit with the hole H,. But since pins P P cannot be respectively inserted in holes H H said frame is raised by the heights of pins P P Accordingly, if the heights of pins P P are assumed to be length of A f, the above-mentioned objects can be accomplished and the lens can be advanced by wellknown means, such as a helicoid or like means.

In connection with FIG. 1, FIG. 2 and FIG. 4, the sensitive paper 20 of sheet form and cut in regular sizes is piled up on the upper portion of machine, with the sensitive surface facing downward. It is pulled out, sheet by sheet, by paper feeding rollers 25, when a print switch button 36 is pushed. In order to prevent the sheets of sensitive paper 20 from being sent out more than two sheets at a time, friction plates 21 made of sponge, rubber or the like are used, and guide

plates

22, 23, and 24, which prevent meandering of said sensitive paper are also used for changing the advancing direction of the sensitive paper. Further, the paper feeding rollers 25 are rotated through a transmission gear comprising a motor 27,

sprocket wheels

28, 29, pulleys 26 and 30, a chain 31, a belt 33 and a shaft 32, until the front end of sensitive paper 20 reaches to a microswitch 34, whereby said microswitch is opened and motor 27 is stopped (see FIG. .12), so that two sheets of sensitive paper are not transported. During this time, a sheet of sensitive paper 20 is taken between rollers 41 and 41' and fed continuously between corona electrification devices 37 to become sensitive to light, and then fed to the exposure surface through rollers 42 and 42'.

A movable contact of the other microswitch provided in parallel with the microswitch 34 is initially in contact with a terminal to which a resistor R,, neon lamp Ne and resistor R are connected, as illustrated in FIG. 12, and moves so as to contact the other terminal to charge a condenser C, through a rectifier'39 when an actuater thereof is pushed by the front side or edge of said sensitive paper 20 passing across the same. However, the actuator of said microswitch returns to unactuated position to return the movable contact to said initial position when the rear side or edge of the sensitive paper is passed completely across the actuator and thus the condenser C, discharges charged current through the resistor R,, neon lamp Ne and resistor R and illuminate the lamp Ne. Accordingly, the collector current of a transistor TR is increased and as relay RY, is operated to close-circuit the contact point RY,A, relay RY, is operated to change contact point RY A over to contact point RY B. Therefore, the main motor 40 and related rollers are all stopped, while the sensitive paper 20 is stopped at exposure position, and simultaneously the

lamps

5 and 6 are lit and the exposure is commenced. However, the charge charged into the condenser C, is gradually discharged according to a time constant as established by R,, R VR and C,, the collector current of TR being thereby decreased and RY, and RY; being recovered after several seconds. In consequence, illuminating

lamps

5 and 6 are extinguished and again the main motor 40 is rotated, and the sensitive paper 20 is fed out of the exposure frame. Further, a variable resistor VR is used for adjusting the operational time for the timer.

In FlG.lS showing constructional details in the neighborhood of the exposure frame, rollers on the side of sensitive film (opposite the flat transparent plate 10, and also on the side of lenses) of sensitive paper 20 are all driven rollers, and the bearings of all

other rollers

41', 42, 43, 45 are so arranged as to be pushed to the counter driving rollers by spring pressure slidably as shown in FlG.l6. Namely, in FlG.l6, a bearing 92 slidable along a notched groove of a holding plate 91 and a spindle 97 of driven roller 41 is inserted in said bearing, and a metallic stopper 93 is provided for avoiding dropping-off of said bearing. A spring 94 is held with two pins to push down bearing 92. The above-mentioned construction is a mere example, and other equivalent constructions may be as well used. Further the driven roller 43 as illustrated in FIG. 15 is pushed by one end of a lever 44 which is tensioned by a spring 29 and pivoted on a pin 44 suitably secured to the copying machine body and thus said driven roller always urged to a driving roller 43.

On the other hand, each of

drivingrollers

41, 42, 43', and 45 possesses a sprocket wheel 46 respectively as shown in FlG.lS, and is connected with chain 47 through sprocket 48 and idle pulley 49, and rotated by main motor 40 through electromagnetic clutch 40'.

As apparent from the foregoing descriptions, consideration will now be given to the film surface side and rear surface side of sensitive paper 20 separately. Between both sides, since there is no power transmission mechanism on the roller surface excepting the frictional transmission on said surface, said construction can be incorporated with the film surface side and with rear surface side respectively. Thus, the rear surface side can be alone separated, opened and closed, and moreover when opened, all the driven rollers can be stopped. Therefore, the sensitive paper 20 can be easily taken out, or focusing can be performed easily. If, on the contrary, the film surface side of sensitive paper 20 is operated for driving the roller, instead of as in the construction of the present embodiment, it is very difficult to design a construction wherein the said driven roller shaft does not project, and it is obvious that such a construction can not be realized. Further, when both driving rollers and driven rollers are presented, the situation will become even more difficult.

Further, as a means for feeding sensitive paper 20 in the above-mentioned copying machine, the belt conveyor shown in FIGS. to 8 is recommended. More particularly, an endless belt 57 is incorporated with or separately secured with a large number of flexible sucking discs 58; said belt being hung over

rollers

59 and 79, either of which rollers, for instance, one of the rollers 59 is set as the driving roller and opposed to a roller 107 which imparts suction to the suctioning discs, while the other 79 is opposed to a hook means 108 for separating sensitive paper from the sucking discs. A pair of rollers 109 and 109' is provided at the near downward portion to said hook so as to feed the sensitive paper. In addition, when sensitive paper is introduced in a space between

rollers

59 and 107, the sucker 58 of belt 57 will be compressed with said two rollers and will be passed through said rollers with said sensitive paper, while the interior air is forced out. Therefore, the suckers 58 passing through said two rollers advances with said sensitive paper being sucked thereagainst and the paper thus approaches the stopping position for exposure. Then, the exposure is completed with images of original figures being projected onto the sensitive paper through lens 9, and again belt 57 proceeds, accompanied by the sensitive paper. As it passes along the curve of roller 79, the outside length becomes large and suckers 58 are deformed correspondingly. Sensitive paper can not correspond thereto, and air is lost due to the deformation. Automatically, the sensitive paper is peeled off separately, and said paper is guided to feeding rollers 109 and 109' by the separating hook 108 which serves also as a guiding member to proceed downward to the following step.

According to the present embodiment, since the sensitive paper is fed between rollers together with flexible sucking discs incorporated or separately provided in a transporting endless belt, the sensitive paper cannot slide, but is firmly and closely kept in position due to the sucking action of many sucking discs. Moreover, shadows from the previously employed clipping bars and hooks are avoided and do not appear on the copying surface. Further, high priced and complicated means for vacuum suction purposes is not required.

Next, FIG. 17 is a perspective view of an exposure frame and driving rollers, according to the present invention. All references in FIG.17 correspond to those of FIG. 2. 50 denotes the machine bed of the present copying machine; 51 denotes a pair of supporting brackets; 52 denotes a pin mounted on said supporting bracket, said pin being engaged with holes 53 formed in the plate 98 and being so composed as to rotate a driving system block as represented by two point-chain lines, and when closed, a recess groove 56 of lever 55 is engaged with pin 54 secured to exposure frame body 98, thereby retaining a clearance between the flat transparent plate 10 and rear plate 10'. Furthermore, 60 denotes a developing vessel for developing the sensitive paper 20 already exposed.

One of the features of the copying machine according to the present invention lies in that a next sensitive paper 20 is drawn into an exposure position, i.e., into clearance between the transparent focusing glass 10 and rear plate 10' for commencing the next exposure, while the sensitive paper 20 already exposed is continuously pulled in the developing vessel 60, thereby providing a continuous copying velocity being capable of being abruptly increased.

Generally, in the automatic copying machine, the sensitive paper is usually fed at a predetermined velocity through all the steps excepting the stationary period during said exposure stage. For instance, in the electronic copying machine, the sensitive paper is fed in order through all the steps from the feeding-in of sensitive paper through charging, exposing and drying (fixing) or the like at constant velocity, excepting the exposure.

Furthermore, in order to manufacture a plurality of copies continuously from the same manuscript (objects), each time the sensitive paper is stopped, the distance between the sensitive paper advanced during the time and that just stopped is extended and it is reasonable that the copying velocity per minute is decreased. During the steps of electrification, development, drying and so forth, the velocity of movement is required to be rather uniform, or else in the finishing of the figures there occur troubles such as uneveness in electrification and the finish of figures, uneveness in the development and uneveness in drying, all of which remarkably damages the quality of the pictures.

An object of the present invention is to continuously effect the copying operation at highest efficiency within the required limitation of paper feeding velocity in the development and drying stages by possibly shortening the distance between sheets of sensitive paper during the exposure. In order to accomplish such an object, according to the present invention, an intermittent feeding device for sensitive paper as shown in FIG.18 can be proposed. The object or original 3 is put on the stand glass plate 2 so as to contact images on the object to be copied with the plate 2. When the surface of the object is illuminated by a suitable light source, the optical path from the object is bent by means of the plane reflecting mirror 8 and the image on the object is projected onto the sensitive paper 20 through the lens assembly 9 and the flat transparent plate 10 and copies onto the sensitive paper which is fed prior to the exposure in position between the flat transparent plate 10 and the rear plate 10' located in parallel with the trans parent plate and closely thereto. Further, another means, for instance, a plane rear plate 10 formed with a number of small holes, without using the flat transparent plate 10, the air existing between the sensitive paper and plane rear plate is evacuated out by a suctioning device (not illustrated), so that said sensitive paper is sucked to the surface of said plane back plate and simultaneously transported. Furthermore, when the distances from

rollers

42 and 42', 45 and 45' are longer than the sensitive paper, rollers 43 and 43' for transporting said sensitive paper with only both ear portions thereof being clamped are used. The reference letters a-e show the sensitive papers occupying the drying, developing position, a position between exposing and developing positions, exposing and awaiting position, respectively. In the above-mentioned construction, all the rollers driven by the motor 40 are stopped, when the sensitive paper is fed into the exposing position, by means of the

microswitches

34, 35 and the related mechanism as described hereinbefore, the lamps and 6 (FIG. 2) illuminating to commence the exposure. When the circuit recovers after an appropriate period of time has elapsed, by means of a timer in the circuit, the above-mentioned illuminating lamps are extinguished, said rollers begin to rotate, and the sensitive paper after exposure is discharged by rollers 45 and 45'. When the front side of the exposed sensitive paper abuts and presses the actuators of microswitches 34', 35' at the lower end of the exposing position, this actuates the microswitches so as to commence the feeding of the next sensitive paper tothe exposing position through rollers 42 and 42'. On the other hand, the preceding exposed sensitive paper is guided by a guide plate 61, and introduced into a developing vessel 60 by rollers 62 and 62', and developed by developing solution 64. After a squeezing out of the excess amount of solution by

rollers

63 and 63 the developed wet sensitive paper is transferred by a conveyer belt to a heater 82 to dry the same, and the paper is discharged from the machine. The development vessel illustrated is a single bath type, but a two or more bath type vessel can, of course, be worked out similarly. Moreover, any dry type developing means may be used for the present copying machine in lieu of the wet one.

In the above-mentioned construction, the features of this embodiment of the present invention, which are useful for shortening the distance between each of the sensitive papers, include that the feeding velocity for the sensitive papers, i.e., circumferential velocity of

rollers

25, 41, 42, 43', and 45', is increased to several times the feeding velocity for rollers subsequent to the roller 62 and simultaneously the resulting deflection of the sensitive paper is temporarily taken out of the regular passage to avoid effect on the velocity of feeding sensitive paper for the developing and drying (fixing) stages.

This will further be explained in connection with F [618, wherein C is the sensitive paper which is entering the developing vessel 60 after the exposure finished, the front end of said sensitive paper approaching the vessel from rollers 45, 45' to 62, 62' along the shortest course. However, since the feeding velocity of

rollers

45, 45 is higher than that of

rollers

61, 62, the later half of the sensitive paper forms a loop outside the passage as apparent in FIG.18, and the tail of the sensitive paper passing through rollers 45, 45' turns as shown and assumes an are like shape as shown in the thick dotted lines. Meanwhile, the next sensitive paper a' is drawn into the exposure position and it is arranged that c may pass through rollers 62, 62' completely until the exposure finished.

As apparent from the foregoing operations, the continuous copying capacity N in a fixed period of time is shown substantially as in the following formula;

10 wherein S: distance (cm) between the sensitive papers,

respectively at waiting and exposing positions W: length of sensitive paper (cm) v: sensitive paper feeding velocity (cm/sec) until the paper entering the developing vessel, i.e., circumferential velocity of

rollers

25, 41, 41', 42, 42' 43, 43, 45, 45'.

'r: exposure time.

The above-shown S. W. 1- are constant according to each copying machine, and can not be altered abruptly, but u can be changed relatively easily.

As described above, since the capacity of copying machines is limited according to the developing and fixing, usually it is limited to approximately 3 cm/sec, while, on the contrary, according to the present invention, the velocity can be increased to approximately 10 cm/sec. The practical examples for both cases will be described as follows:

Assuming that S 9 cm, W= 21 cm (Japanese Standard Paper Sizes: A4), and 'r 4 sec, when u 3 cm/sec, N 4.3 sheet/min; when u 10 cm/sec, N 8.6 sheet/min. Namely, the copying velocity can be doubled.

As ahead runing sensitive paper passes through rollers 62, 62' in seconds 7 seconds, copying can be continued without overlapping.

Next, the sensitive paper enters the developing vessel as described above. Driving

rollers

62, 63 and driving pulley 77 possess sprocket wheel 73 respectively, and rotate by the transmission mechanism of chain 76 through motor 72, sprocket wheel 75 and idle pulley 74; and a conveyor belt 81 is rotated by driving pulley 77 and driven pulley 78. Furthermore, the developing vessel 60 is provided with a guide plate 65 for guiding passage of sensitive paper and with a developing electrode 66 adjacent the sensitive plane. Sensitive paper is advanced through the clearance. Further, as shown in FIG. 1, 67 denotes a jet pipe for developing solution; 68 denotes a solution supplying pipe; 69 denotes a drain hole; 70 denotes a liquid delivery pipe for discharging a liquid to the developing tank. The surfaces of liquidsqueezing rollers 63 and 63' are cleaned by a cleaner 71. On the other hand, a dryer is located at the middle of the conveyor belt 81, heat light rays issued by a drying heater 82 are collected by a reflecting cap 83 to illuminate the dried surface and simultaneously heat particularly between the bottom plate 84 and top plate 5 85 at high temperature. Further, 86 denotes a fan for accelerating the drying; 87 denotes heat insulating plates for protecting the reflecting mirror 8 and lens 9 or the like from heat, and the sensitive papers completely dried are gathered in a paper receiving member 89. Further, 90 is a fan for dispersing the heat accumulated in the upper portion outside the machine. FIGS. 13 and 14 represent a sheet number dial counting device which records the number of sheets copied, wherein denotes a rotary solenoid, 111 denotes a rectifier and 112 denotes a sheet number dial. Another exposure device may also be made so as to disconnect the feeding rollers within the exposure range of sensitive paper sucked to the casing, through action of a solenoid. Moreover, in an optical device, the projection is made on the surface of said object through a lens system, a transparent flexible belt and a cloth or rubber or the like flexible belt are provided in contact with each other, and said contact surface is made to be coincident with the focal plane of said optical device, and the transparent belt is arranged at the lens side, and sensitive paper is put between both belts and exposed by projection through the transparent belt. Simultaneously the transportation of said sensitive paper is stopped by the interlocking of those belts. Further, as another embodiment of the sensitive paper feeding devices, a transport member having an insulating resistor is used to attract and transfer the sensitive paper electrostatically.

What we claim is:

1. An electronic photocopying machine comprising a magazine containing a plurality of papers stacked therein each of which papers is coated with a photoconductive insulator on one side; a first feeding mechanism for feeding said papers sequentially from said magazine; means for providing electrostatic charges to the photoconductive insulator on the thusly fed paper so as to impart a photosensitive property thereto; a second feeding mechanism for introducing the thusly photosensitized paper to a predetermined exposure position; an exposure frame including driven rollers and a transparent plate at said exposure position; said second feeding mechanism including a pivotal assembly which comprises a plurality of driving rollers, a motor to drive said driving rollers, and a hooked lever means having a lever member with a notch adapted for engaging a fixed pin to secure the pivotal assembly in a predetermined position with respect to said exposure frame, in which position a predetermined space is provided between the assembly and transparent plate for passage of photosensitive paper and said driving rollers oppose the driven rollers for feeding the paper through said space; a lamp means for illuminating an object to be copied; an optical system for projecting an image of the object onto the paper at the exposure position, said first and second feeding mechanisms including feeding means which are inoperative for a predetermined period for effecting exposure and operative subsequently to transfer the thusly exposed paper; a developing means to develop the image on the photosensitive paper; a fixing means to fix the image thereon; a third feeding mechanism for feeding the exposed photosensitive paper through the developing means and fixing means at a relatively lower feeding velocity than those of the other feeding mechanisms so that the paper is formed into a temporary loop; an endless belt on at least two of said driving rollers, and flexible sucking discs on said belt, said paper being sucked and transferred by said flexible sucking discs with the aid of one of said driven rollers.