US3529360A - Reprographic output feed system - Google Patents

Description

R. B. KOSTEN ETA!- REPROGRAPHIC OUTPUT FEED SYSTEM 2 Sheets-Sheet 1 Filed Nov. 4, 1968 Se t. 22, 1970 R. B. KOSTEN ETAL 3,529,360

' REPROGRAPHIC OUTPUT FEED SYSTEM Filed Nov. 4, 1968 2 Sheets-Sheet 2 RICHARD B.KOSTEN SARANTOS MOUSTAFELLOS A T TOR/VF Y United States Patent 3,529,360 REPROGRAPHIC OUTPUT FEED SYSTEM Richard B. Kosten, Bayside, and Sarantos Moustafellos, Forest Hills, N.Y., assignors to Ing. C. Olivetti & C., S.p.A., Ivrea, Italy, a corporation of Italy Filed Nov. 4, 1968, Ser. No. 772,916 Int. Cl. F26b 13/08 US Cl. 34-449 9 Claims ABSTRACT OF THE DISCLOSURE An output copy feed system for reprographic apparatus is described in which air flow is used to control the movement of copy paper over a folded output path to a stacking tray.

BACKGROUND OF THE INVENTION Reprographic machines utilize a number of process steps each requiring a certain amount of space and processing time. When the effective speed of one process step is increased so that copy being processed can move faster, the processing path length for another process step must often be increased so that processing time for that step will remain the same. To accommodate such longer processing path lengths, it is desirable to fold the processing paths as compactly as possible to keep total apparatus bulk to a minimum. The image fixing (i.e., fusing, drying, etc.) and paper discharge path frequently require both an undesirably long length and a vertical or upwardly directed rise portion.

There are a number of ways for handling the upward motion of the copy paper, for example, traveling vacuum platens, sequences of pinch rollers and grippers operating with a cylinder or traveling web. These various approaches generally complicate the image-fixing process as well as adding expense in the form of considerable hardware to the apparatus.

It is a further difficulty of prior apparatus that discharged copy paper often fails to stack properly. Particularly in reprographic machines using rolled copy paper, the output copy frequently curls into a rolled or folded condition disrupting the stacking.

SUMMARY OF THE INVENTION In accordance with the present invention, the copy paper in a reprographic machine moves in an upward direction on a heated web for fixing of the image and is held firmly against the web for good thermal contact by air pressure directed against the image bearing surface of the copy so as to aid in fixing the image at the same time it secures the copy to the Web for upward travel.

Turnaround deflection at the top of the upward travel is aided or entirely provided by air jets, the air flow from which continues to control the motion of the copy paper as it drops to the stacking tray. Thus it is an object of the invention to provide a pneumatically controlled output copy feed for reprographic apparatus.

It is a further object to provide copy fixing processing on an upwardly moving heated web upon which copy paper is secured and the image fixed with the help of a stream of air directed against the image-bearing surface of the copy paper.

It is a further object to provide reprographic apparatus having a vertically folded image-fixing and output 3,529,360 Patented Sept. 22, 1970 ice BRIEF DESCRIPTION OF THE DRAWINGS DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a longitudinal section of an electrophotographic copying machine according to the invention with much of the detail omitted. The main components of the copying machine are depicted. Copy paper supply is shown as paper roll 10 at a first end of the machine. Paper knife 11, of the rotary type, is provided to cut the copy paper to length. A vacuum platen 12 serves as an exposure bed. Platen 12 is essetnially in the center of the machine, while knife 11 is between paper roll 10 and platen 12. Underneath platen 12 is developing unit 14. At the opposite end of the machine from paper roll 10 is the drying and output feed system 15.

A stationary subject window 16 for positioning an original to be copied is supported a distance above and facing platen 12. Between window 16 and platen 12 is optical system 17 supported on a pair (one shown) of rods 18 for movement between the ends of the machine.

Optical system 17 has support-housing 20 serving to hold the different components of the optical system rigidly in their respective relative positions. Support-housing 20 also blocks stray light and reduces dust within the optical system.

Housing 20 when moved nearest the end of the machine occupied by output feed system 15, has first end 21 extending beyond subject window 16 and platen 12. In the same position, the opposite end of housing 20 extends far into the space between window 16 and platen 12. In the illustrated embodiment this is slightly more than halfway.

Second end 22 of housing 20 holds reflex lens assembly 24. Lens assembly 24 is a cylindrical case 25 containing an objective lens 26 and a mirror 27. Lens 26 faces end 21 of housing 20. Mirror 27 is behind lens 26 being further from end 21.

Adjacent to end 21, housing 20 supports two mirrors 28 and 30 positioned to form a right angle. Each of the mirrors is rectangular and of a length adequate to intercept the light bundle representing a full width section of a document to be copied. This length is perpendicular to the plane of the drawing and is not shown. Mirrors 28 and 30 are joined along lengthwise edges to form a right angle junction 31.

The opposite lengthwise edges of mirrors 28 and 30 are positioned near end 21 of housing 20 while junction 31 projects toward lens assembly 24. Right angle junction 31 is positioned half the optical distance between the top surface of platen 12 and the top surface of window 16. This middle position of mirror junction 31 gives a one-to-one magnification ratio. For other ratios the position can be shifted. The mirror surface at junction 31 also lies on the optical axis of lens 26. This latter relation should be held irrespective of magnification ratio.

Reflective surface 32 of mirror 28 is coated on the side of mirror 28 nearest lens assembly 24. This places the reflective surface at the air-mirror interface. While this is not essential, it is desirable to avoid reflective and refractive effects of the glass or other transparent medium that supports the reflective surface. It also permits the reflective surface to be supported by an opaque substrate.

Housing 20 has an opening 34 above mirror 28 to permit light to pass between subject window 16 and mirror 28. Housing 20 also has an opening 35 below mirror 30 to permit light to pass between mirror 30 and platen 12. The reflective surface 36 of mirror 30 is coated on the side nearest lens assembly 24 as in mirror 28. Mounted on top of housing 20 between opening 34 and lens assembly 24 is lamp 40. Lamp 40 has a light source 41 positioned in a reflector assembly 42. Lamp 40 is situated to provide a maximum illumination to a section of window 16 facing mirror 28 through opening 34 without illuminating mirror 28 directly. Electrical means (not shown) are provided for energizing lamp 40.

A second reflector assembly 44 is mounted to the top of housing 20 near end 21 to reflect scattered light back toward window 16.

The whole of housing 20 is canted so that the end carrying lens assembly 24 is entirely above the center line between the top surface of window 16 and the top surface of platen 12. In the embodiment illustrated, canting of housing 20 shifts the optical axis of lens assembly 24 about from the horizontal axis defined by traverse rods 18.

Canting of housing and the optical system places the lens assembly up close to window 16 leaving sufficient room beneath housing 20 for paper roll 10 and paper knife 11 when optical system 17 is moved to that end of the copying machine.

Platen 12 is supported adjacent to a plenum 46, which is evacuated by a blower 47. Apertures in platen 12 provide a rarefied pressure zone over the top surface of platen 12. The low-pressure zone holds a copy sheet flat on platen 12 during exposure. Turnaround shield 50 at the end of platen 12 guides copy paper back below the platen to second deflecting shield 51 and a pair of pinch rollers 52.

Shield 51 deflects copy paper down into the nip of rollers 52, which are arranged to drive the copy paper into developer tray 14. Second pair of pinch rollers 54 are positioned to catch copy paper leaving developer tray 14 and direct it against vertical-moving drying belt 56. Rollers 54 are adapted to remove excess developer liquid from copy paper.

Belt 56 is supported on rollers 57 and 58. Roller 57 is driven by a motor (not shown) whereby belt 56 rises vertically adjacent to rollers 54 and descends adjacent to the end of the copying machine farthest from paper roll 10. Electrically heated plate 60, positioned adjacent to the back of the rising portion of belt 56, heats belt 56 to a drying temperature.

Turnaround shield 61 positioned above roller 58 is arranged to deflect copy paper around roller 58 and down out of the end of the machine.

A series of curved rods 62 serve to guide the output path of the paper. Hopper 63 connected to the end of the machine catches the copy paper leaving the machine and serves as an output basket.

Plenum chamber 65 pressurized by blower 111 (FIG. 2) extends across the vertical-rise face of belt 56. Output passage 66 indicated by arrow 67 is arranged to provide a flow of pressurized air against the rising surface of belt 56. Output passage 70 indicated by arrow 71 is arranged to provide an additional flow of pressurized air against the bottom or concave side of turnaround shield 61.

Air flow to plenum chamber 65, in one embodiment, has been provided by single air blower 111 depicted in FIG. 2. Air blower 111 is situated at the bottom of the machine against the further side relative to FIG. 1. Thus, looking at FIG. 1 it would be behind air blower 47. Air intake 112 of blower 111 is preferably arranged to take air from the region of lamp 40 so as to provide cooling air flow for lamp 40 and, at the same time, provide warm air at the intake for better drying. Air conduit 113 is connected between output 114 of blower 111 and input 116 of plenum chamber 65. Conduit 113 is arranged along the bottom of the machine against the side wall and behind developing unit 14 relative to FIG. 1. In the vicinity of plenum chamber 65, air conduit 113 turns upward to connect with chamber at the side of the chamber. FIG. 2 is drawn looking from the opposite side of the machine from that illustrated in FIG. 1.

A portion of plenum chamber 65 is extended over roller 58 and turnaround 61 to form partially enclosed air passage 117. Air passage 117 conducts the air flowing from the air jet formed by passage so that it provides pressure against copy paper leaving the machine. Referring to FIG. 1, it will be seen that this pressure is applied against the back side of the trailing portion of the copy paper. This air pressure prevents the trailing portion of the copy paper from curling and pushes it out away from the machine so that the copy paper falls face down in hopper 63.

The copy paper flow in the operation of the reprographic apparatus illustrated in FIG. 1 is depicted by dash line 101. The copy paper leaves paper roll 10 and passes through a first set of drive rollers to a paper knife 11. From the paper knife, it passes through a second set of drive rollers to a vacuum platen 12.

The apparatus in FIG. 1 is depicted as an electrophotographic machine and includes a dual corona, charging or sensitizing device 38 between the paper knife and the vacuum platen. After a predetermined length of the copy paperfor example, ll-inch standard or 14-inch legalhas passed paper knife 11, the knife is actuated to cut the paper.

The vacuum pulled against vaccum platen 12 by blower 47 operating through plenum chamber 46 holds the copy sheet firmly against platen 12 for exposure and movement. Apertures for air passage (not shown) are provided in platen 12 for this purpose. After the copy sheet has reached the exposure position on platen 12, scanning motor 93 is actuated to move optical system 17 in a pass over platen 12 so that it scans an original to be copied situated on subject window 16 and provides an image on the copy sheet.

As optical system 17 moves, light from source 41 is directed against a portion of the original being copied and is reflected in image configuration through aperture 34 onto mirror surface 32. From mirror suface 32 the image illumination is reflected through lens 26 to mirror 27, which in turn reflects it back through lens 26 to mirror surface 36. From mirror surface 36 the image illumination is reflected through aperture 35 onto a segment of the copy sheet.

After the copy has been completely exposed to the image, light source 41 is extinguished and optical system 17 returns to its starting position. At the same time, platen 12 is restarted and carries the exposed copy paper through turnaround 50 to pinch rollers 52, which drive the copy sheet through developing unit 14. Developing unit 14 is depicted as a liquid developer processing station in which a liquid developer carries a suspension of electroscopic ink particles.

As the developed copy sheet leaves developing unit 14 it is picked up by pinch rollers 54, which serve both to drive the developed copy sheet forward to output system 15 and, at the same time, to remove excess liquid from the sheet. Pinch rollers 54 drive the copy sheet against vertically moving belt 56. As the copy sheet starts moving upward with belt 56 a jet of air from plenum 65 is directed by passage 66 against the copy sheet to press the copy sheet against belt 56 while at the same time providing a drying flow of air. Additional drying is provided by heated plate 60 contacting the back surface of belt 56. Heated plate 60 heats belt 56, which in turn heats the copy sheet for drying. Belt 56 carries the copy sheet vertically to a turnaround 61. The output of turnaround 61 directs the copy sheet against curved rods 62, which serve to guide the copy sheet into output hopper 63.

An additional air jet through passage 70 from plenum 65 facilitates the movement of the copy sheet in the output path. As the leading edge of the copy sheet reaches passage 70 adjacent to turnaround 61, the air flow from passage 70 pushes the leading edge of the paper around in a curved manner assisting the turnaround shield.

As the lagging edge of the sheet reaches turnaround 61, the sharply curved path causes the rear edge of the sheet to kick out against the turnaround so that the air flow switches from the image side of the copy sheet to the back side. This air flow follows the lagging edge of the copy sheet to the output feed end of turnaround 61 and pushes the lagging edge of the copy sheet outward away from the machine so that the copy sheet stacks properly in hopper 63.

This proper guidance of the output path with the air flow is particularly significant in reprographic apparatus of the type depicted in FIG. 1 since the copy paper originating from a roll tends to curl so that there is a tendency for the outcoming sheet to curl in upon itself with consequent disruption of stacking.

Turnaround deflector 61 of FIG. 1 is a mechanical means assisted by air flow to change the direction of copy paper movement. This change in direction can also be provided entirely by air jets. Thus, FIG. 3 shows an alternative embodiment of plenum chamber 65 in which turnaround 61 is replaced by a series of air jets 118, 119, 120 and 121. While these air jets are depicted in a series distributed along air passage extension 117, many variations are possible and the number of jets used is not critical. Full turnaround can be obtained with a single jet properly placed and with adequate air pressure. By extending plenum chamber 65 into passage 117, the space into which jets 118 through 121 operate is restricted permitting the use of lower air pressure and less total air flow for the desired results.

As previously described, in relation to FIG. 1, the air jets are arranged so that as the lagging edge of a copy sheet passes, the air stream switches to the back side of the copy sheet. Thus, as the copy sheet lagging edge reaches jet 121 of FIG. 3, that portion of the copy paper is held between the air pressure from jet 121 on the image side and the air pressure from jets 118, 119 and 120 on the reverse side. As the copy paper lagging edge passes jet 121, all pressure is transferred to the reverse side and the lagging edge is forced outward away from the apparatus as desired for stacking.

FIG. 2 depicts the alternative arrangement of plenum 65 shown in FIG. 3 rather than that depicted in FIG. 1.

While the present invention has been described with relation to specific embodiments, these are only exemplary preferred embodiments and it is intended to claim the invention broadly within the spirit and scope of the following claims.

We claim: 1. An output copy feed system for reprographic apparatus comprising:

(a) a conveyor for transporting developed copy from a developing processor to an elevated position;

(b) deflecting means at said elevated position for abruptly changing the direction of copy paper being transported;

(c) first air jet means for providing air flow against copy being transported between said processor and said elevated position so as to secure said copy against said conveyor;

(d) second air jet means for providing air flow against copy at said elevated position so as to aid said deflecting means in changing the direction;

(e) means to provide air under pressure to said first and said second air jet means; and,

(f) output copy guide and stacking means for receiving copy from said conveyor.

2. An output copy feed system according to claim 1 wherein an air passage at said elevated position is arranged to conduct air from said second jet to control the output movement of copy over said copy guide and to said stacking means.

3. An output copy feed system according to claim 2 in which said first air jet means and said second air jet means comprise output passages of a single plenum chamber, whereby air flow from a single source performs the four functions of holding copy paper against a rising conveyor, drying developed copy on said conveyor, cushioning the deflection of copy during abrupt direction change, and controlling the output movement of copy into stacking means.

4. An output copy feed system according to claim 2 in which said air passage is an extension of said means to provide air under pressure and partially encloses the copy feed path at said elevated position.

5. An output copy feed system according to claim 1 in which said conveyor is a heated belt, whereby said heat together with the air flow from said first air jet and said second air jet provides fixing of said developed copy.

6. An output copy feed system according to claim 1 in which said deflecting means is a turnaround guide which changes the direction of copy paper movement from an upward direction to a downward direction.

7. An output copy feed system according to claim 1 in which said means to provide air is a single plenum chamber pressurized by a single air blower.

8. An output copy feed system according to claim 1 in which said second air jet means provides a cushion of air between said deflecting means and said copy, whereby said copy is gently guided in the direction defined by said deflecting means.

9. An output copy feed system according to claim 8 in which said deflecting means has a sharp enough curvature to cause the trailing edge of copy passing said second air jet to spring away from said conveyor and contact said deflecting means, whereby the air stream from said second air jet is switched from one side to the other side of copy providing air flow along a secondary passage controlling the output movement of said copy.

References Cited UNITED STATES PATENTS 2,138,178 11/1938 Lang 34-l62 3,102,006 8/1963 Cohn et al 34-156 X EDWARD J. MICHAEL, Primary Examiner

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