1. Field of the Invention
The present invention relates to a sheet finisher including a punching unit and more particularly to an image forming system in which the sheet finisher is constructed integrally with or separately from an image forming apparatus.
2. Description of the Background Art
Today, a copier, printer or similar image forming apparatus with a sheet finisher including a punching unit is extensively used. Japanese Patent Laid-Open Publication No. 2001-25995, for example, discloses an image forming apparatus including a punch and a die for punching a sheet, scrap conveying means for conveying the resulting scraps, and a scrap box for storing the scraps. The scrap conveying means is implemented as a screw type conveyor while the scrap box is removably mounted to the outside of the apparatus body. When the scrap box is dismounted from the apparatus body, the scrap conveying means stops being driven, but the apparatus continues its image forming operation. This, according to the above document, not only prevents the scraps from being scattered around the apparatus body, but enhances productivity as to image formation.
However, the problem with the image forming apparatus described above is that the scrap box is mounted on the rear of the apparatus body, as seen from the operation side. The scrap box is therefore difficult to handle although image formation may be continued after the removal of the scrap box.
Japanese Patent Laid-Open Publication No. 7-112861, for example, teaches an image forming apparatus including a container or storing means for storing scraps produced from punched sheets. The container is mounted to or dismounted from the apparatus body via an opening formed in the side wall of the apparatus body. Further, the container is formed of transparent plastics or similar material so as to allow the container to be seen from the outside. The above document additionally proposes an arrangement in which the container is mounted to one side of the apparatus body, so that scraps stored in the container can be dealt with at the outside of the apparatus body. However, the container mounted on the side of the apparatus body needs an exclusive space for the replacement of the container beside the apparatus body. Further, because the container cannot be extended deep into the apparatus body, punching must be performed in the vicinity of the side wall of the apparatus body. It is therefore necessary to limit the direction of sheet conveyance in accordance with the punching position.
Further, Japanese Patent Laid-Open Publication No. 6-155393, for example, proposes an image forming apparatus including a punching mechanism mounted on an openable cover forming part of one side of the apparatus body. Scraps produced by the punching mechanism are stored in a tank removably mounted to the apparatus body. The openable cover, however, needs an exclusive space beside the apparatus body, so that the cover can be opened. It follows that a space broad enough for the tank to be removed is required beside the apparatus body, increasing the overall space to be occupied by the apparatus.
The conventional image forming apparatuses of the type including a sheet finisher with a punching unit have other problems left unsolved, as enumerated below.
(1) When scraps produced from a sheet by the punching unit drop, they should be surely received by a belt including in a scrap conveying unit. To meet this requirement, the belt must be provided with a length great enough to convey the scraps over a distance between, among a plurality of holes, holes at opposite ends, i.e., 80 mm in Japan or 240 mm in Europe. Also, the belt must be positioned beneath the plurality of holes. Further, it is likely that the scraps fail to fully part from the belt due to static electricity.
(2) The scrap box mounted on the rear of the apparatus body is not only difficult to handle, but also problematic when it is dismounted because image formation is continued, i.e., scraps are continuously produced.
(3) To solve the above problem (2), the scrap box or scrap storing means may be mounted on the front of the sheet finisher. This, however, gives rise to another problem that when the scraps conveyed by the scrap conveying means toward the scrap box have fibers appearing on their edges, they are caught by adjoining members and cannot be smoothly or surely introduced into the scrap box.
Technologies relating to the present invention are also disclosed in, e.g., Japanese Patent Laid-Open Publication Nos. 6-155393, 2000-334696 and 2001-25995.
It is an object of the present invention to provide a small size, space saving sheet finisher easy to handle and allowing scraps to be dealt with only at the operation side, and an image forming system using the same.
It is another object of the present invention to provide a sheet finisher capable of surely introducing scraps in scrap storing means and efficiently using a space, and an image forming system using the same.
It is another object of the present invention to provide a sheet finisher capable of introducing scraps in scrap storing means without causing them to drop to the outside or being scattered around, and an image forming system using the same.
It is another object of the present invention to provide a sheet finisher capable of causing scraps to drop into scrap storing means in the form of a pile as flat as possible, and an image forming system using the same.
It is another object of the present invention to provide a sheet finisher capable of forcibly removing scraps from scrap conveying means before the scraps again enter the sheet finisher via a front side wall, and an image forming system using the same.
It is another object of the present invention to provide a sheet finisher capable of surely conveying scraps with a belt, and an image forming system using the same.
It is another object of the present invention to provide a sheet finisher capable of removing scraps from a stripe-like conveying surface at an adequate position and introducing them in a hopper, and an image forming system using the same.
It is still another object of the present invention to provide a sheet finisher not needing an exclusive motor for scrap conveying means, and an image forming system using the same.
It is yet another object of the present invention to provide a sheet finisher capable of surely conveying scraps without regard to whether or not image formation is under way, and an image forming system using the same.
It is a further object of the present invention to provide a sheet finisher capable of surely introducing even scraps with fibers appearing on their edges into scrap storing means, and an image forming system using the same.
A sheet finisher of the present invention includes a punching unit configured to punch a sheet handed over from an image forming apparatus to the sheet finisher. A scrap conveying unit conveys scraps produced from the sheet punched by the punching unit. A hopper stores scraps conveyed thereto by there scrap conveying unit. The hopper is mounted on the front side of the sheet finisher.
The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description taken with the accompanying drawings in which:
Preferred embodiments of the image forming system in accordance with the present invention will be described hereinafter.
Referring to
The document scanning section 31 is configured to scan a document with a scanner in the main scanning direction while moving the scanner in the subscanning direction. The document feeding section (ADF (Automatic Document Feeder) hereinafter) 34 feeds the document to a glass platen.
The image writing section 32 is implemented as conventional optics including a laser diode, a polygonal mirror, and an fθ lens. The optics optically scans the surface of a photoconductive element for thereby forming a latent image. The latent image is then developed by toner. The resulting toner image is transferred from the photoconductive element to a sheet or recording medium and then fixed by a fixing unit. Subsequently, the sheet with the fixed toner image is handed over from the image forming apparatus PR to the sheet finisher FR.
In the illustrative embodiment, the sheet feeding section 33 has four sheet feeding stages stacked one above another. A vertical sheet path 36 extends from the pay-out side or right side, as viewed in
The sheet carrying the toner image thereon and driven out of the image forming apparatus PR is introduced into the sheet finisher FR in a direction indicated by an arrow M. The sheet finisher FR includes a punching unit 4 for punching the sheet introduced into the sheet finisher FR. The punching unit or punching means 4 is positioned downstream of an inlet roller pair 1 in the direction of sheet conveyance, but upstream of a roller pair 6. A scrap conveying unit or conveying means 5 is positioned beneath the punching unit 4 for conveying scraps produced from punched sheets. More specifically, as shown in
More specifically, the operator replaces toner or removes a jamming sheet by opening a front cover 14 forming part of a housing on the operation side OP. A hopper or scrap storing means 3 is mounted on the inside of the front cover 14, so that the scraps are conveyed to the hopper 3 in the direction Q. The scrap conveying unit 5 and hopper 3 assigned to the scraps will be described more specifically later. The front cover 14 may be provided with a transparent window 14c, so that the operator can see the inside of the hopper 3. In the illustrative embodiment, the window 14c is so positioned as to allow the operator to see the top opening of the hopper 3. The window 14c is implemented by a sheet of glass or transparent resin (see
The sheet P punched by the punching unit 4 is steered by path selectors 27 and 28 to be stacked on a shift tray 9 by way of, e.g., a stapling station. Alternatively, the sheet P may be simply driven out to a proof tray 29.
More specifically, in a sort mode, the path selector 27 is so positioned as to steer the sheet P to a path on which a roller pair 7 is located. The sheet P is then driven out to the shift tray 9 via the roller pair 7 and an outlet roller pair 8. The tray 9 is shifted-in the direction perpendicular to the direction of sheet conveyance copy by copy, thereby sorting the consecutive sheets P on a copy basis.
In a staple mode, the path selector 27 is so positioned as to steer the sheet 2 to a path on which a roller pair 10 is located. The sheet P is then conveyed to a staple tray 12 by the roller pair 10 and a roller pair 11. Every time one sheet P is brought to the staple tray 12, a knock roller knocks it downward toward a rear fence. After a preselected number of sheets P constituting a single copy have been stacked on the staple tray 12, a stapler 13 staples one end, trailing edge in the illustrative embodiment, of the sheet stack. Subsequently, a belt conveys the stapled sheet stack upward toward the outlet roller pair 8. As a result, the stapled sheet stack is also driven out to the shift tray. 9.
As stated above, the punching unit 4 and hopper 3 are positioned upstream of all of the other finishing stations in the direction of sheet conveyance and can therefore punch any kind of sheet.
The reference numerals 2 and 45 in
FIGS. 5 shows a positional relation between the scrap conveying unit 5, the punching unit 4 and the hopper 3. As shown, the punching unit 4 includes two punches 15 arranged side by side in the direction Q. A sheet brought to the punches 15 while being guided by a sheet guide 15a is stopped there for a moment, and then the punches 15 are moved downward to punch the sheet. Scraps 23 produced from the sheet by the punches 15 drop on a belt 18 included in the scrap conveying unit 5 and positioned beneath the sheet guide 15a. The belt 18 is passed over a drive timing pulley 19 and a driven timing pulley 17 with preselected tension. The upper run of the belt 18 on which the scraps 23 drop moves in the direction Q to convey the scraps 23 toward the operation side OP, i.e., the front cover 14.
More specifically, a worm wheel 19a is formed integrally with the drive timing pulley 19 and held in mesh with a worm 20. The worm 20 in rotation causes the belt 18 to turn counterclockwise, as viewed in
The scrap guide 16 includes a tubular guide 16a whose inner periphery has an arcuate section and a slope guide 16b inclined toward the inlet of the hopper 3. The upper end of the slope guide 16b adjoins part of the belt 18 passed over the driven timing pulley 17.
In the illustrative embodiment, the driven timing pulley 17 protrudes into a space between the front cover 14 and the front side wall 45 of the apparatus body, so that the scraps 23 are handed over from the belt 18 to the guide 16 in the above space. The hopper 3 is positioned below such a position. Therefore, the hopper 3, scrap guide 6 and at least part of the timing pulley 17 are positioned between the front cover 14 and the front side wall 45.
The magnetic force of the magnet 25 must be great enough to support the hopper 3 even when the hopper 3 is filled with the scraps 23. Such a magnetic force, however, is sufficient in consideration of easy mounting or dismounting of the hopper 3. It is noteworthy that the front cover 14 is opened and: closed in the event of jam processing and toner replacement as well and causes the hopper 3 to vibrate. As a result, the pile of scraps 23 in the hopper 3 collapses and allows the hopper 3 to accommodate more scraps 23.
As shown in
As shown in
Reference will be made to
The CPU 360 controls the various operations of the sheet finisher FR in accordance with the above inputs: the up-down movement of the punches 15, operation of the scrap conveying unit 5, jogging operation effected on the staple tray 13 in the direction perpendicular to the direction of sheet conveyance, stapling by the stapling unit 13, discharge of a stapled sheet stack, movement of the shift tray 9, operation of the knock roller and so forth. Pulse signals input to a staple motor, not shown, that drives the roller pair 11 are counted by the CPU 360 and used to control the knock roller and jogging.
It is to be noted that the CPU 360 controls the sheet finisher FR in accordance with a program stored in a ROM (Read Only Memory), not shown, while using a RAM (Random Access Memory), not shown, as a work area.
Referring to
A stepping motor 34 drives a pulley 33 mounted on the shaft 31 via a timing belt 35. As for drive transmission from the pulley 33 to the shaft 31, an arrangement may be made such that the pulley 33 is constantly driven by the stepping motor 34 via the timing belt 35 while the rotation of the pulley 33 is transferred to the shaft 31 via a one-way clutch, not shown, as needed. Alternatively, the stepping motor 34 may be selectively driven to transfer its output torque to the shaft 31.
The rotary punching system described above can punch successive sheets without stopping them and therefore makes it needless to care about the image forming speed. In addition, control is simplified because the sheet P does not have to be stopped.
This embodiment differs from the previous embodiment in that it additionally includes means for sensing the full state of the hopper 3 and means for determining whether or not the hopper 3 is mounted at a preselected position. As for the rest of the construction, the illustrative embodiment is identical with the previous embodiment, so that identical structural elements are designated by identical reference numerals and will not be described specifically.
As shown in
In the illustrative embodiment, when the output of the sensor 43 indicates the full state of the hopper 3 or the absence of the hopper 3, image forming operation is inhibited in order to prevent the scraps 23 from dropping to the floor. More specifically, the CPU 360 inhibits image, forming operation when the hopper 3 is unable to be used, as sensed by the sensor 43. For this purpose, the output of the sensor 43 is also sent to the CPU 360 via the I/O interface 370.
The sensor 43 is implemented as a reflection type sensor or photoreflector. Therefore, when the sensor 43 senses reflection, the shutter 44 is held in the lowered position of
The sensor 43 and shutter 44 both are mounted on the scrap guide 16 while the scrap guide 16 is constructed as part of the scrap conveying unit 5. It is therefore possible to assemble the entire scrap conveying unit 5 as a unit in a factory and then put it on the market as a unit.
In the embodiments shown and described, the hopper 3 is magnetically supported on the inner surface of the front cover 14 and moved together with the front cover 14. However, the crux is that the hopper 3 be positioned inside of the front cover 14. As shown in
As stated above, in the first to third embodiments, the scrap storing means is mounted on the front side of the sheet finisher, i.e., at the same side as the operation side of another apparatus that hands over a sheet to the sheet finisher or on an openable door parallel to the direction of sheet conveyance and capable of uncovering the inside of the sheet finisher. This realizes a small size, space saving sheet finisher easy to operate and allowing sheet scraps to be dealt with only at the operation side, and an image forming system using the same.
This embodiment is essentially similar to the first embodiment described with reference to
In the first embodiment, the belt 18 conveys the scraps 23 toward the front or operation side in the direction Q over the front side wall 45, as stated with reference to
By contrast, as shown in
If desired, the guide surface 16b with a single ridge 16b may be replaced with a division plate or flap-like plate configured to divide the scraps 23 flowing along the inclined surface of the scrap guide 16.
As shown in
As shown in
As stated above, the screen plate 46 unblocks the outlet 16c of the scrap guide 16 only when the front cover 14 is opened, allowing the scraps 23 to drop into the hopper 3. This prevents the scraps 23 from dropping via the scrap guide 16 during or after the opening of the front cover 14.
As shown in
In light of the above, as shown in
As stated above, the illustrative embodiment has various unprecedented advantages, as enumerated below.
(1) The scraps are conveyed to the front side of the sheet finisher over the front side wall of the sheet finisher and can therefore be surely conveyed to the space outside of the front side wall.
(2) The scraps are surely conveyed to the above position without dropping in the sheet finisher or between opposite side walls. This allows the space beneath the punching means to be efficiently used for thereby reducing the size of the finisher.
(3) The scrap guide means guides-the scraps from the scrap conveying means to the scrap storing means while dividing the scraps in at least two directions. The scraps therefore do not pile in the scrap storing means via a single position, so that the space available in the scrap storing means is efficiently used.
(4) The scrap guide means includes the screen plate configured to allow the scraps to drop from the scrap guide means into the scrap storing means in interlocked relation to the front cover only when the front cover is closed. This prevents the scraps from being scattered around when the front cover is opened.
(5) The removing means forcibly removes the scraps from the scrap conveying means and causes them to drop into the scrap storing means. The scraps can therefore be surely introduced into the scrap storing means without again entering the sheet finisher.
In the four-hole punching unit of
The timing belt applied to the belt 18 may be one whose opposite surfaces are toothed or one toothed on only one surface and turned in sideout. The timing belt toothed on both surfaces is expensive and thick and therefore undesirable from the space standpoint. While the timing belt toothed on one side is free from such a problem, it should be driven at speed low enough to obviate slip because the flat surface of the belt is be passed over the timing pulleys 17 and 19.
As stated above, in the illustrative embodiment, the distance over which the scrap conveying means conveys the scraps is greater than the distance between the punching means, so that the scraps can be surely conveyed by the conveying means. Further, the surface of the conveying means is so configured as to contact the scraps over a minimum of area, thereby reducing electrostatic adhesion to act between the belt and the scraps. This allows the scraps to surely part from the conveying means at an adequate position and fall in the hopper.
More specifically, as shown in
The worm 20 is formed with a spur gear portion at its base portion. When the spur gear portion is brought into mesh with a gear 101, the belt 18 can be driven. The timing belt 21 is passed over the pulley portion of the gear 101 and driven by the stepping motor 22. At the same time, a pulley 100 engaged with the inlet roller pair 1,
Reference will be made to
If the sheet does not have to be punched (NO, step S3), then the stepping motor 22 stops operating just after the sheet has moved away from the inlet roller pair 1, thereby saving power.
As stated above, in the illustrative embodiment, a single drive source drives both of the scrap conveying means and sheet conveying means, i.e., an exclusive motor for the scrap conveying means is not necessary. The scrap conveying means is therefore reduced in cost and weight and therefore easy to mount to the sheet finisher.
Further, the belt is continuously driven until the scraps dropped on the belt all have been collected in the hopper. The scraps can therefore be surely conveyed without regard to the image forming operation. This prevents the scraps from dropping or being scattered around inside the sheet finisher.
As shown in
To solve the above problem, as shown in
In the sheet finisher FR of the illustrative embodiment, when a sheet is driven out to the shift tray 9 or the proof tray 29, a stop signal is sent to the image forming apparatus PR. In response, the stepping motor 22 is caused to move in the reverse direction over a preselected period of time and then move in the usual direction for scrap conveyance. As a result, the-scrap 23 caught between the belt 18 and the blade 48 successfully drops into the hopper 3. Such a specific procedure is shown in
Another specific procedure is shown in
As for the distance of reverse movement of the belt 18, as shown in
To move the belt 18 by the distance L4 in the reverse direction, a number of pulses corresponding to the distance L4 should only be input to the stepping motor 22, as shown in
As shown in
In summary, the illustrative embodiment has various advantages, as enumerated below.
(1) The scrap conveying means is moved in the reverse direction to convey the scraps by a preselected distance in the direction opposite to the direction in which the conveying means conveys them toward the guide means. Therefore, even when the fibers of the scraps are caught between the guide means and the conveying means, such scraps can be surely released and smoothly introduced into the scrap storing means.
(2) The scrap conveying means is implemented as an endless belt, so that the scraps with the fibers can be removed by a simple operation.
(3) Even when the scraps are not removed due to the turn-off of the power switch or a sheet jam, they can be surely removed later.
(4) The scrap storing means is positioned at the front side or operation side of the sheet finisher and is therefore easy to handle.
(5) The scrap storing means is mounted on the inner surface of the openable door and therefore saves size and space and is easy to operate. In addition, the scrap storing means is removable from the above door.
(6) The relation of Db<Da is established to prevent the scraps from dropping from the most upstream portion of the scrap conveying means when the power switch of the image forming apparatus is turned on or when the door is opened. More specifically, the scrap conveying means is not moved in the reverse direction more than necessary, so that the scraps do not drop to the side opposite to the scrap storing means. In addition, the minimum necessary movement is successful to save power.
Various modifications will become possible for those skilled in the art after receiving the teachings of the present disclosure without departing from the scope thereof.
Number | Date | Country | Kind |
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2002-066421 | Mar 2002 | JP | national |
2002-082433 | Mar 2002 | JP | national |
2002-162121 | Jun 2002 | JP | national |
2002-162131 | Jun 2002 | JP | national |
2002-274815 | Sep 2002 | JP | national |
Number | Date | Country | |
---|---|---|---|
Parent | 10385489 | Mar 2003 | US |
Child | 11594084 | Nov 2006 | US |