1. Field of the Invention
The present invention relates to a stacking device, which stores recording media with images formed thereon and delivers the recording media to a post-processing machine so as to stack the media, and also relates to an image forming apparatus comprising the stacking device.
2. Description of the Related Art
An image forming apparatus is provided with a stacking device which delivers recording media with images formed thereon, to a post-processing machine. The post-processing machine performs, for example, a shifting process, a punching process, a binding process, a gluing process, etc.
For example, Jpn. PCT National Publication No. 9-507716 discloses an intermediate storage section comprising a plurality of partial storage units for temporarily stored recording media on which images have been formed by a printer. The intermediate storage section is connected to a job finishing device. Further, recording media are taken out of the plurality of partial storage units, and managed by the job finishing device in accordance with a document.
According to an embodiment of the present invention, there is provided a stacking device comprising a carry-out section which stores a plurality of sheets of recording media conveyed in from a carry-in section, into a storage space formed along vertical directions, and delivers the stored plurality of recording media to a device for a later process, the stacking device further comprising: a contact section with which top ends of the recording media in a conveying direction, conveyed into the storage space, make contact to stop the recording media at a storage position; a media move section which comprises a plurality of partition members, forms a plurality of spaces capable of storing the recording media between the partition members, stores the recording media stopped at the storage positron into arbitrary one of the plurality of spaces, and moves the partition members thereby to move at least a part of the top ends of the recording media to a pushup position different from the storage position; and a lift section which pushes up, to the carry-out section, the recording media moved to the pushup position by the media move section.
Additionally, an embodiment of the present invention provided an image forming apparatus comprising: a supply section which supplies a long continuous recording medium; an image forming section which performs image forming on the continuous recording medium; a cutter section which cuts the continuous recording medium recorded by the image forming section, into recording media each having a predetermined size; a media conveyor section which conveys the continuous recording medium from the supply section to the cutter section; a stacking device which is provided below the cutter section, performs a stacking process of stacking the cut recording media, and delivers the recording media stacked, to a device for a later process; and a controller which controls at least the supply section, the image forming section, the cutter section, the media conveyor section, and the stacking device, wherein the stacking device comprises a carry-in section which conveys the recording media cut by the cutter section, into a storage space formed along vertical directions, a carry-out section which delivers the recording media in a plurality stored in the storage space, to the device for the late process, a contact section with which top ends of the recording media in a conveying direction, conveyed into the storage space, make contact to stop the recording media at a storage position, a media move section which comprises a plurality of partition members, forms a plurality of spaces capable of storing the recording media between the partition members, stores the recording media stopped at the storage position into arbitrary one of the plurality of spaces, and moves the partition members thereby to move at least a part of the top ends of the recording media to a pushup position different from the storage position, and a lift section which pushes up, to the carry-out section, the recording media moved to the pushup position by the media move section.
Advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention, and together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the invention.
Hereinafter, an embodiment of the present invention will be specifically described with reference to the drawings.
The stacking device according to the invention temporarily stores sheet-type recording media which are ejected sequentially from a eject port of an image forming apparatus, with the recording media bent in a direction perpendicular to a conveying direction so as to tension the recording media. After thus storing a prespecified number of recording media, the stacking device delivers the stacked and aligned recording media to the post-processing machine provided for a later process, maintaining a state for receiving new recording media. For example, when rectangular recording media each having major and minor edges are conveyed in a direction along the major edges, the minor edges perpendicular to the conveying direction are bent to be round or two ends thereof are bent so as not to be too sharp.
The image forming apparatus may be a printer represented primarily by an inkjet printer, or a copying machine. Further, recording media may be conveyed into the stacking device which performs a stacking process, from the image forming apparatus, or conveyed into a sorter mechanism attached to the image forming apparatus. The post-processing machine is, for example, a device which performs a shifting process, a punching process, a binding process, a gluing process, etc.
A stacking device 1 is constituted by a device body section 2, a recording-media carry-in section 3, a recording-media carry-out section 4, and a recording-media disposal section 5. The stacking device 1 comprises an unillustrated controller which controls the device body section 2, recording-media carry-in section 3, recording-media carry-out section 4, and recording-media disposal section 5.
The recording-media carry-in section 3 is constituted by an inlet guide 11, a media detector 12, and paired inlet rollers 13. The inlet guide 11 guides sheet-type recording media 10 to convey in. The media detector 12 detects recording media 10 passing the inlet guide 11. The paired inlet rollers 13 are to convey the recording medium 10 into the device body section 2 described later.
The rotational speed of the paired inlet rollers 13 is set so as to elongate an interval between one another of recording media which are sequentially conveyed in. That is, a speed at which a recording medium is conveyed out by the paired inlet rollers 13 is set to be greater than a speed at which a recording medium is conveyed into the paired inlet rollers 13. At the media detector 12, a light emitting section and a light receiving section are provided to face each other in a manner that an opening provided in the inlet guide 11 is interposed therebetween. When a recording medium passes the media detector 12, the media detector 12 detects the recording medium from a top end to a rear end thereof since the recording medium shields light from the light emitting section.
The recording-media carry-out section 4 is constituted by paired pickup rollers 14, a carry-out guide 15, and paired carry-out rollers 16. The paired pickup rollers 14 pick up stacked and aligned recording media lifted by a lift section 41. The carry-out guide 15 and the paired carry-out rollers 16 are to convey out recording media to the post-processing machine provided for a later process. The paired pickup rollers 14 and paired carry-out rollers 16 each may appropriately comprise a one-way clutch.
As illustrated in
A contact drive section 32 opens/closes the sheet contact section 31 at a timing based on a detection signal from the media detector 12. Now, a non-contact position is defined to be a state in which the sheet contact section 31 is opened. At this non-contact position, an unwanted recording medium is conveyed to the recording-media disposal section 5. In other words, when the sheet contact section 31 is at the non-contact position, recording media are out of contact with the sheet contact section 31. Otherwise, a storage position (or contact position) is defined to be a state in which the sheet contact section 31 is closed. At this contact position, recording media to be stored make contact with the sheet contact section 31 in a storage space (hereinafter referred to as a storage space A) in the device body section 2 denoted at reference symbol A in
In each of the paired rollers described above, at least one roller is a drive roller and the other one is a driven roller. Although no drive source for any drive roller is illustrated, a known motor and a transmission mechanism, such as gears and/or a belt, are used.
The device body section 2 conveys out unwanted ones of the recording media 10 having a defined size, to the recording-media disposal section 5. The device body section 2 stores a plurality of recording media together to be delivered to the post-processing machine, and convey the plurality of recording media to the recording-media carry-out section 4, with the plurality of recording media stacked and aligned (in a stacked state).
Roughly divided, the device body section 2 is constituted by a base member 21, carry-in guide sections 22 and 23, a tension guide section 24 which tensions the recording media (to be firm), impellers 25 and 26, a fan 27, paddle rollers 28 and 29, a sheet contact section 31, and a lift section 41.
As illustrated in
As illustrated in
The carry-in guide sections 22 and 23 are provided between the impellers 25 and 26 in a side of the paired inlet rollers 13. As illustrated in FIG. IE, an angle of the carry-in guide section 22 is adjusted in a manner that a top end of the recording medium 10 to be conveyed in are positioned between blades of the impeller 25. The same thing applies to the carry-in guide section 23.
The carry-in guide sections 22 and 23 are provided in order to inhibit upper ends (rear ends in the conveying direction) of recording media 10 stored previously in a posture described later, from colliding with a top end of a recording medium to be conveyed subsequently in the conveying direction, when recording media 10 are stored sequentially. The carry-in guide sections 22 and 23 each are formed to have a curved surface (collision surface) made of metal which is slippery for the recording media 10 or made of hard resin. Alternatively, the carry-in guide sections 22 and 23 may be supported on a back surface (a non-collision surface) thereof to be floated by an elastic member such as a spring, so as to absorb rebound of the top ends of the recording media 10 when the top ends collide with the carry-in guide sections 22 and 23.
As illustrated in
The fans 27 as an air blower are provided near the carry-in guide sections 22 and 23. The fans 27 send air to stored recording media, thereby pushing the recording media 10 to the base member 21. That is, the fans 27 serve a function to create a gap between the stored recording media 10 and the carry-in guide sections 22 and 23, and to prevent a top end of a recording medium 10 being conveyed through the carry-in guide sections 22 and 23 from making contact with rear ends of stored recording media 10. Therefore, the fans 27 may be provided upon necessity.
The paddle rollers 28 and 29 as a conveyor assist mechanism are provided respectively in two sides of the tension guide section 24. The paddle rollers 28 and 29 have soft blade parts which are made of, for example, rubber or resin. The paddle rollers 28 and 29 are a conveyor assist mechanism which conveys a recording medium 10 to a further downstream side when the recording medium 10 comes to receive no conveying force any more while the recording medium 10 is being stored (e.g., when a rear end of the recording medium is moved to a downstream side of the paired inlet rollers 13). Further, the paddle rollers 28 and 29 are controlled to be driven by a roller drive section 33, and rotate at the same rotational speed as the paired inlet rollers 13.
Each of the impellers 25 and 26 as a media move section is configured by uniformly attaching a plurality of blades to a cylindrical axle provided to extend in vertical directions (or in the conveying direction). In this manner, a plurality of spaces are created between the blades. In the present embodiment, six blades are provided. The plurality of blades are formed of an elastic member, such as metal, resin, or hard rubber, for example. Accordingly, even if a top end part of the blades makes contact with the surface of the base member 21 when the impellers 25 and 26 rotate, the top end can pass through as the top end slightly flexibly bends. After the top end passes, the blades recover an original shape.
The conveyed recording medium 10 is guided by the carry-in guide sections 22 and 23, and is stored in a manner that two sides of the recording medium 10 falls respectively between the blades of the impeller 25 and between those of the impeller 26. Although the present embodiment exemplifies impellers each comprising six blades, the number of blades is not limited to six.
The impellers 25 and 26 rotate at the time of delivery to the post-processing machine, as described later, and bend (press), toward the base member 21, two sides of one or a plurality of stacked and aligned recording media 10 in a top end side, which are stored in one space of the plurality of spaces created between blades. By this press, the two sides of the recording media 10 in the top end side are moved from the sheet contact section 31 to a side or lift tables 45 and 46. In other words, by rotating the impellers 25 and 26, at least one of parts of the stored recording media which are in contact with the sheet contact section 31 is moved to a position (pushup position) where the recording media are out of contact with the sheet contact section 31. By this pressing, the recording media 10 are stored with center parts of the recording media 10 bent by a convex part of the base member 21, where viewed from upside. This bending is performed in a direction opposite to bending by the tension guide section 24.
Immediately thereafter, a first recording medium is conveyed in from among a next stacked group. At this time, the conveyed recording medium is stored between different blades from those described above.
The sheet contact section 31 forms a plate-like shape, and aligns top ends of recording media 10 fed by the paddle rollers 28 and 29 by bringing the top ends into contact with a plate surface. At this time, as described above, the recording medium 10 is tensioned to be firm by bending. A position where the recording medium 10 collides with and is brought into contact with the sheet contact section 31 is referred to as the storage position.
The sheet contact section 31 is moved (reciprocally moved in a direction horizontal to an installation surface) by the contact drive section 32. When the device is stopped and started, the sheet contact section 31 is located at a non-contact position as illustrated in
A recording medium which is conveyed in when the sheet contact section 31 is at the non-contact position does not make contact with the sheet contact section 31 but is directly guided to the paired eject rollers 17. A procedure of disposing of an unwanted recording medium will be described later. Otherwise, when an instruction to deliver stacked recording media to the post-processing machine for a later process is given from the controller, the sheet contact section 31 is moved to the contact position by the contact drive section 32. At this contact position, the sheet contact section 31 makes contact with the conveyed recording media 10 and stores the plurality of recording media 10 together at the storage position.
The sheet contact section 31 may have elasticity in a direction toward the contact position. The elasticity acts to an extent that eject of a recording medium is not obstructed when the sheet contact section 31 makes contact with an unwanted recording medium being ejected for disposal. The sheet contact section 31 may be formed in a convex shape by recessing parts where the lift tables 45 and 46 are provided.
Next, a configuration of the lift section 41 will be described.
As illustrated in
The fixing/support members 42 (42a and 42b) and 43 (43a and 43b) fix the guide axles 44 (44a and 44b) to a back surface of the base member 21. The guide axles 44 (44a and 44b) are provided to extend in vertical directions (upward/downward direction) in a side of the back surface (a surface where the impellers 25 and 26 are not provided). The lift, tables 45 and 46 are attached to the guide axles 44 (44a and 44b) by the support members 47 and 48. Recording media are placed on the lift tables 45 and 46, which deliver the placed recording media to the recording-media carry-out section 4. The support members 47 and 48 support the lift tables 45 and 46 to be movable along the guide axles 44. Further, the link member 49 connects the support members 47 and 48 to each other. Notches 51 are provided in the base member 21 so as to allow the lift tables 45 and 46 to be raised and lowered.
As illustrated in
To raise and lower the lift tables 45 and 46, various known drive mechanisms may be employed, such as a drive mechanism using a ball screw, a cylinder mechanism using oil or air, a drive mechanism using pulleys and a wire, or a drive mechanism using a magnet (e.g., a linear motor).
When the lift tables 45 and 46 are at the down position, the lift tables 45 and 46 are set to be positioned lower than the sheet contact section 31 in a manner that a gap which allows recording media to pass through is formed between a lower surface of the sheet contact section 31 and upper surfaces of the lift tables 45 and 46. At this time, the lift tables 45 and 46 are also positioned such that the lift tables 45 and 46 do not make contact with the sheet contact section 31 even when the lift tables 45 and 46 are pushed up.
Next, a stacking process of the stacking device 1 configured as described above will be described with reference to a flowchart in
At first, the device is started and initialized by turning on a main power supply (step S1). At this time, the other image forming apparatus and the post-processing machine are also started. In place of starting the devices individually, the stacking device and post-processing machine may be configured to be started together when the image forming apparatus is started up.
In initialization, whether the sheet, contact section 31 is positioned at the non-contact position or not and whether the lift tables 45 and 46 are positioned at the down position or not are checked. If the sheer contact section and the lift tables are not positioned respectively at the non-contact position and the down position, the sheet contact section and the lift tables are respectively moved to the contact position and the down position. Further, driving of each of constitutive sections is started.
Next, the disposal process for unwanted recording media is performed (step S2). The disposal process will be described with reference to the flowchart of
In this manner, if step S11 determines that there is any unwanted medium 10a (YES), whether all unwanted media 10a have passed through the media detector 12 or not is monitored (step S12). Otherwise, if not all unwanted media 10a have passed yet (NO), monitoring is continued until all unwanted media 10a have passed.
Otherwise, if the media detector 12 detects a rear end of a last unwanted medium 10a in the conveying direction (YES), the sheet contact section 31 is moved to the contact position after elapse of a predetermined time period (step S13). Specifically, as illustrated in
In the middle of moving the sheet contact section 31 to the contact position, the sheet contact section 31 makes contact with the unwanted medium 10a. However, the sheet contact section 31 and lift tables 45 and 46 are configured to creating a gap as described previously. Therefore, the unwanted medium 10a is conveyed through the gap by a conveying force of the paired carry-out rollers 16. Further, as illustrated in
Thus, before the last unwanted medium 10a is stored into the disposal tray 20, the sheet contact section 31 is started to move to the contact position. In this manner, for example, as illustrated in
Otherwise, if step S11 determines that there is no unwanted medium 10a (No), processing goes to step S13, and the sheet contact section 31 is moved to the contact position. The disposal process is then ended and returns.
Next, recording media to be stored 10b which are conveyed in for the stacking process are sequentially brought into contact with the sheet contact section 31 and stored into the storage position (step S3). Further, whether a specified number of recording media to be stored 10b have been stored or not is determined by the media detector 12 (step S4). The number of recording media to be stored 10b to be stored in the stacking device 1 is included in the information which the controller of the stacking device 1 has been notified of from the controller of the image forming apparatus in the disposal process described previously. The present embodiment is supposed to store two recording media to be stored 10b (10b and 10b2).
A first recording medium, to be stored 10b1 conveyed in from the inlet guide 11 passes the media detector 12 and reaches the paired inlet rollers 13. The media detector 12 detects top and rear ends of the recording medium to be stored 10b1, and counts the number of recording media to be stored passing. The recording medium to be stored 10b1 is conveyed in between blades of the impellers 23 and 26 through the carry-in guide sections 22 and 23. At this time, the rear end of the recording medium to be stored 10b1 goes out of the paired inlet rollers 13. However, the recording medium to be stored 10b1 is pulled down by the paddle rollers 28 and 29 and brought into contact with the sheet contact section 31, to be stored there. At this time, the recording medium to be stored 10b1 is conveyed, guided by the tension guide section 24.
In this manner, as illustrated in
In addition, air is sent to the recording medium to be stored 10b1 by the fans 27. Therefore, a gap is created between the rear end of the recording medium to be stored 10b1 and the carry-in guide sections 22 and 23. In this state, a subsequent second recording medium to be stored 10b2 is conveyed in between blades of the impellers 25 and 26 through the carry-in guide sections 22 and 23. At this time, a top end of the recording medium to be stored 10b2 makes contact with a surface part of the recording medium to be stored 10b1, and does therefore not cause jamming. Accordingly, as illustrated in 5B, a specified number of recording media to be stored are stored.
In step S4, if the number of stored media reaches the specified number (YES), the impellers 25 and 26 are rotated with the recording media to be stored 10b1 and 10b2 stored and aligned. Further, two side ends of each other the recording media to be stored 10b1 and 10b2 are moved from the sheet contact section 31 to the lift tables 45 and 46 (step S5). Otherwise, if the number of stored media does not yet reach the specified number (No), further recording media to be stored are continuously stored.
In step S5, a timing to rotate the impellers 25 and 26 is elapse of a predetermined time period from detection of the recording medium to be stored 10b2 by the media detector 12. That is, at the timing when the recording media to be stored 10b1 and 10b2 are set on the sheet contact section 31, the impellers 25 and 26 rotate.
The impellers 25 and 26 are rotated respectively in arrow directions from a state illustrated in
Further, whether there are recording media to be stored 10c1 and 10c2 to be stored next or not is determined (step S6). Information concerning whether there are recording media to be stored to be stored next or not is included in information which the controller of the stacking device 1 is notified of from the controller of the image formation apparatus.
In step S6, if there are recording media to be stored to be stored next (Yes), the recording medium to be stored 10c1 has been conveyed immediately after the recording medium to be stored 10b2, as illustrated in
That is, as illustrated in
At the same time when the recording medium to be stored 10c1 is stored, the lift tables 45 and 46 are raised along the guide axles 44 (step S7), to push up the recording media to be stored 10b1 and 10b2 stacked and aligned. The recording media to be stored 10b1 and 10b2 pushed up are nipped by the paired pickup rollers 14 rotating.
Thereafter, the recording media to be stored 10b1 and 10b2 are conveyed to the post-processing machine for a later process through the carry-out guide 15 by the paired carry-out rollers 16. At this time, the newly stored recording medium to be stored 10c1 is not in contact with the lift tables 45 and 46, and therefore, only the recording media to be stored 10b1 and 10b2 can be pushed up, as illustrated in
Thus, by rotating the impellers 25 and 26, an operation of conveying out the recording media to be stored 10b1 and 10b2 and an operation of conveying in the recording media to be stored 10c1 and 10c2 can be performed simultaneously, and high-speed processing can be thereby achieved. The lift tables 45 and 46 return to the down position before the operation of conveying in the next recording media to be stored 10c1 and 10c2 starts after the operation of conveying out the recording media to be stored 10b1 and 10b2 ends.
Otherwise, if there are no recording media to be stored to be stored next (No) in step S6, processing goes to step S8, and the lift tables 45 and 46 are raised to the up position, thereby to convey the recording media to be stored 10b1 and 10b2 stacked and aligned, to the post-processing machine for a later process, as illustrated in
As has been described above, in the stacking device according to the invention, a top end bent by the guide section is brought into contact with the sheet contact section when a recording medium is stored into the storage space A. The recording medium is therefore stored so as to stand up tensioned. Therefore, even a soft recording medium is prevented from becoming puckered by, for example, breakdown (bending or twisting) due to contact, and jam errors are prevented.
Further, by keeping recording media parallel to the direction of gravity, an installation area occupied by the stacking device can be reduced to a small size. Accordingly, when the stacking device is mounted on an image formation apparatus or a sorter, increase in apparatus area can be suppressed to be small.
The stacking device comprises a disposal path in addition to a conveyance path for delivering recording media to the post-processing machine for a later process. When the stacking device is mounted on a printer or a copying machine, unwanted media are sorted out for stacking for trial printing, and output to the disposal tray. Accordingly, unwanted recording media are not stored but are prevented from being delivered to the post-processing machine in the rear step, and manual work for taking out recording media can be omitted.
The two paths are switched from each other, i.e., selected by moving the sheet contact section 31 provided at a bottom of the storage space A, parallel to an installation surface thereof, like a shutter. Further, recording media which have been once stored in the storage space A can be securely ejected to a side of the disposal path, by rotating the paddle rollers 28 and 29 to push out the recording media and by further causing the paired eject rollers 17 to nip and take out the recording media, after retracting the sheet contact section 31.
The sheet contact section 31 which stores recording media, and the lift tables 45 and 46 which push up the recording media are located with a step and a gap maintained between each other. The sheet contact section 31 is started to move from the non-contact position to the contact position at a timing at which a last unwanted recording medium is nipped by the paired eject rollers 17. Therefore, an unwanted recording medium is ejected by the paired eject rollers 17 since the gap is created although the sheet contact section 31 is in contact with unwanted recording media. In addition, since the sheet contact section 31 is at the contact position while unwanted recording media are ejected. Therefore, even if an unwanted recording medium and a recording medium to stack are conveyed in, situated close to each other, the recording medium to stack can be securely stored.
Further, by merely rotating the impellers 25 and 26 holding two side ends of a specified number of recording media stacked and aligned, the two side ends of the recording media can be moved from the contact position on the sheet contact section 31 to the pushup position depending on the lift tables 45 and 46. In addition, the recording media are pushed up, guided by blades, and can accordingly be conveyed to the carry-out rollers without putting the recording media out of order.
Hereinafter, descriptions will be made of an example of mounting the stacking device according to the embodiment of the invention on an image forming apparatus, such as an Inkjet printer, in which images are formed on a rolled continuous recording medium (e.g., roll paper) or a fan-folded continuous recording medium.
In the present embodiment, a stacking device is located below a cutter section 186 in an image forming apparatus 101.
Hereinafter, the image forming apparatus 101 will be described.
The image forming apparatus 101 comprises an unwinder section 102 and a printer section 103. The unwinder section 102 will now be described first.
The unwinder section 102 comprises a stand 106, a roll former fixing shaft 107, and a brake 108. The unwinder section 102 is a recording-media supply section which holds a continuous medium 105 to be rotatable by the roll former fixing shaft 107, and supplies the continuous medium 105 to the printer section 103.
In the present embodiment, the unwinder section 102 uses roll paper as the continuous medium. The stand 106 supports the roll former fixing shaft 107 to be rotatable. From the roll former fixing shaft 107, a plurality of claw parts protrude in radial directions, to chuck an inner diameter of a roll former by injecting air from an unillustrated air injection port. As a result, the claw parts of the roll former fixing shaft 107 bite into the inner diameter of the roll former of the continuous medium 105, and firmly hold the continuous medium 105.
The roll former fixing shaft 107 is connected to the brake 108 by a pulley and a belt. A braking force of the brake 108 is transmitted to the roll former fixing shaft 107. In this manner, the brake 108 serves a function to apply a tension in a direction opposite to a conveying direction of the continuous medium 105.
Subsequently, the printer section 103 will be described.
As illustrated in
The control device 195 controls at least: operations of the unwinder section 102 as the recording medium supply section; the conveyor section to convey the continuous medium; the first recording section 150 and second recording section 160 as an image forming section; the first cleaning unit 170 and second cleaning unit 175 cleaning section; the cutter section 186; and the stacking device 1.
The continuous medium 105 introduced into the printer section 103 is conveyed to the first drum 130 through a conveyor system which is constituted by free rollers 114 and 115, a swing roller, free rollers 117 and 118. The swing roller 116 is attached to a top end of an arm 116b which is held to be pivotable about a pivot center 116a on the body frame 125 in a manner that the swing roller 116 is rotatable in regular and reverse directions. Further, the swing roller 116 constitutes a tension generation section which tensions the continuous medium 105 conveyed along a lower circumferential surface of the swing roller 116 by the dead weight of the swing roller 116 and arm 116b.
Further, even if the continuous medium 105 is loosened by fluctuation of the tension which is caused by eccentricity of the continuous medium 105 held by the unwinder section 102, the aforementioned tension generation section has a function to eliminate looseness.
The pivot center 116a is provided with a potentiometer 116c which detects a pivot position when the swing roller 116 moves in vertical directions. Depending on an output signal of the potentiometer 116c, the brake 108 connected to the roll former fixing shaft 107 of the unwinder section 102 is operated. In this manner, the tension of the continuous medium 105 is controlled. The free rollers 114, 115, 117, and 118 are rotatably supported by the body frame 125.
The continuous medium 105 conveyed to the first drum 130 through the aforementioned conveyor system is wound about the first drum 130 to a winding angle of 330 degrees by the free rollers 118 and 119. The first drum 130 is, for example, a hollow cylinder made of aluminum, and a rotation axle 130a is rotatably supported by the body frame 125. Further, the continuous medium 105 held on the first drum 130 is conveyed to immediately below the first recording section 150 provided to face the first drum 130, and recording is performed on a surface of the continuous medium 105 by the first recording section 150.
A winding angle of the continuous medium 105 which is wound about the first drum 130 is thus ensured to be as wide as 330 degrees or so, as in the present embodiment. Therefore, the continuous medium 105 can be held in tight contact with the first drum 130, without a slip between the first drum 130 and the continuous medium 105. As a result, accurate conveyance of a paper sheet and accurate rotational speed control of the drum can be achieved.
The continuous medium 105 following an end of winding about the first drum 130, or namely, the continuous medium 105 having a surface on which an image has been recorded is conveyed to the second drum 140 through the conveyor system of the free rollers 119, 120, and 121.
The continuous medium 105 conveyed to the second drum 140 is wound about the second drum 140 to a winding angle of 330 degrees by the free rollers 121 and 122, as in the first drum 130.
The second drum 140 is also, for example, a hollow cylinder made of aluminum, and is rotatably supported by the body frame 125. In addition, the free rollers 119, 120, 121, and 122 are rotatably supported by the body frame 125.
The continuous medium 105 which is wound about the second drum 140 by the winding angle of 330 degrees as described above applies a normal force to an outer circumferential surface of the second drum 140 because of tensions at the beginning and the end of winding.
As a result, a friction force is large between the second drum 140 and the continuous medium 105, and prevents a slip between the second drum 140 and the continuous medium 105. Accordingly, the continuous medium 105 is held in tight contact with the second drum 140.
The second drum 140 rotates in an anticlockwise direction in the figure by a driving force of a drive motor 141 connected to a rotation axle 140a by a pulley and a belt. Thus, the second drum 140 functions as a drive drum, and the first drum 130 is a slave drum which is rotated in a clockwise direction by the second drum 140 through the continuous medium 105.
Further, in accordance with rotation of the second drum 140, the continuous medium 105 which is held on the second drum 140 is conveyed to immediately below the second recording section 160 provided so as to face the second arum 140.
The continuous medium 103 which is wound about and held on the second drum 140 has an image recording surface on which the first recording section 150 has performed recording by the first drum 130. The image recording surface is oriented downward (to a side of a circumferential surface of the second drum 140), and a back surface of the image recording surface is oriented upward (in a direction of facing the second recording section 160).
Recording is performed, by the second recording section 160, on the back surface of the continuous medium 105 which has been conveyed to immediately below the second recording section 160, held on and wound about the second drum 140. Two-sided recording on the continuous medium 105 is thereby completed.
An encoder in a post lion detector is also connected to the rotation axle 140a of the second drum 140. The encoder rotates in accordance with rotation of the second drum 140, and outputs a detection pulse corresponding to the rotational position of the second drum 140.
Further, the detection pulse output from the encoder is input through the control device 195 to an unillustrated drive board which drives recording heads of the first recording section 150 and second recording section 160. In synchronization with the detection pulse, the recording heads discharge ink under control of the drive board.
That is, the continuous medium 105 is conveyed at a uniform speed without slipping on the first drum 130 or the second drum 140. Therefore, driving of discharge from the first recording section 150 and second recording section 160 can be controlled, based on the detection pulse which is output in accordance with rotation of the second drum 140.
Subsequently, the first recording section 150 and second recording section 160 will be described. The first recording section 150 has the same configuration as the second recording section 160, and only the first recording section 150 will be described as a representative.
The first recording section 150 according to the present embodiment comprises recording head sections 151a, 151b, 151c, and 151d for total four colors of cyan (C), black (K), magenta (M), and yellow (Y). In the present embodiment, the recording head sections 151a, 151b, 151c, and 151d are constituted by a plurality of recording heads. The plurality of heads are fixed to a head holder plate 152 over a width equal to or longer than a width of the continuous medium 105. A nozzle surface formed on each recording head is opposed to a print surface of the continuous medium 105 held on the outer circumferential surface of the first drum 130. Relative positions of the head holder plate 152 and the first drum 130 to each other are determined by an unillustrated member.
Subsequently, the first cleaning unit 170 and second cleaning unit 175 will be described. The first cleaning unit 170 and second cleaning unit 175 are provided to clean the recording head sections, and have a function to perform cleaning operations, such as known wiping and nozzle suction.
When the first recording section 150 is cleaned by the first cleaning unit 170, the head holder plate 152 is retracted in a direction of moving away from a circumferential surface of the first drum 130 by an unillustrated retraction mechanism. Accordingly, the recording head sections 151a, 151b, 151c, and 151d are moved in the direction of moving away from the circumferential surface of the first drum 130, and a predetermined gap is created between lower surfaces of the recording head sections 151a, 151b, 151c, and 151d and the circumferential surface of the first drum 130.
Thereafter, the first cleaning unit 170 is moved to immediately below the recording head sections 151a, 151b, 151c, and 151d, and cleaning is performed on the recording head sections 151a, 151b, 151c, and 151d. After completion of the cleaning operation, the first cleaning unit 170 returns to a standby position as illustrated in
As described previously, behind the end of winding of the continuous medium 105 about the second drum 140, the continuous medium 105, two-sided recording of which has been completed by performing recording on a surface by the first recording section 150 as well as on a back surface by the second recording section 160, is conveyed by the conveyor system following the free roller 122.
The continuous medium 105 following the end of winding about the second drum 140 is conveyed to paired first nip rollers 130. The paired first nip rollers 180 are rotatably supported by the body frame 125.
The paired first nip rollers 180 are constituted by a pair of rollers. Though not particularly illustrated, a torque limiter, a reduction gear, and a drive motor are connected to one of the pair of rollers, and convey the continuous medium 105 at the same speed as the conveying speed of the continuous medium 105 on the first drum 130 and second drum 140.
In this manner, the paired first nip rollers 180 constitute a tension generation section to tension the continuous medium 105 in the same direction as the conveying direction.
After the paired first nip rollers 180, the continuous medium 103 is conveyed by paired second nip rollers 184 through free rollers 181, 182, and 183. The free rollers 181, 182, and 183 and the paired second nip rollers 184 are also rotatably supported by the body frame 125.
The paired second nip rollers 184 are constituted by a pair of rollers. Though not particularly illustrated, a torque limiter, a reduction gear, and a drive motor are connected to one of the pair of rollers, and convey the continuous medium 105 toward an insertion guide 185 provided immediately behind, at the same speed as the conveying speed at which the continuous medium 105 is conveyed by the paired first nip rollers 180.
The insertion guide 185 functions to restrict fluctuation of the continuous medium 105 in a thickness direction in this conveyance path, and to insert the continuous medium 105 into the cutter section 186.
The insertion guide 185 is configured to extend in a width direction of the continuous medium 105, cover two surfaces of the continuous medium 105, and restrict the conveyance path. The insertion guide 185 is a component which is made of, for example, sheet metal or molded resin. Alternatively, the insertion guide 185 may be made of paired elongate rollers.
The continuous medium 105 is inserted into the cutter section 186 through the insertion guide 185 from the paired second nip rollers 184. A conveyance path between the paired second nip rollers 184 and the cutter section 186 is configured to be as short as possible.
The cutter section 186 is constituted by an anvil roller 187, a cutter roller 188 opposed to the anvil roller 187, and a brush roller 189 provided in a downstream side of the anvil roller 187 and cutter roller 188 along the conveying direction.
The cutter roller 188 is provided with cutter blades 188a. In the present embodiment, two cutter blades 188a are provided at equal intervals on an outer circumferential surface of the cutter roller 188.
Further, the cutter roller 188 and anvil roller 187 are rotated at the same speed as the conveying speed of the continuous medium 105 on the first drum 130 and second drum 140 and the conveying speed of the continuous medium 105 conveyed by the paired second nip rollers 184 as well. In this manner, the continuous medium 105 can be sequentially cut into sheets of recording media 10 each having a predetermined size.
A friction member made of rubber, a sponge, or any other material is formed on an outer circumferential surface of the brush roller 189. In the present embodiment, a number of linear members which extend in radial directions of the roller are implanted as the friction member. The brush roller 189 prevents a top end of the continuous medium 105 cut by the cutter roller 18b from being rolled in by the cutter roller 188 or the anvil roller 187. Therefore, a linear speed b of outermost circumference of the brush roller 189 is set to be taster than a linear speed a of the cutter blades 188a of the cutter blades 188a. In this manner, the continuous medium 105 can be conveyed without being loosened. The cutter section 186 is configured to be replaceable. Recording media of a plurality of sizes can be output by changing a diameter of the roller and by replacing the cutter section with another cutter section capable of cutting into a desired size.
Sheets of recording media 10 cut by the cutter section 186 are conveyed into the stacking device 1. The stacking device 1 is provided vertically below the cutter section 186, and stacks, aligns, and delivers the sheets of recording media 10 to a post-processing machine, as described previously. Detailed descriptions to a configuration and operations of the stacking device 1 will be omitted herefrom.
In an image forming apparatus in which images are formed by using a continuous recording medium such as roll paper, the continuous recording medium with no image formed thereon remains on a conveyance path from recording heads to a cutter section after completion of a previous image forming operation. Further, when an image forming operation is performed next, the continuous recording medium remaining from the recording heads to the cutter section need be disposed of as an unwanted recording medium. However, the unwanted recording medium is disposed of into a disposal tray 20 by providing the stacking device 1. Therefore, recording media to be stored can be stored and conveyed out to the post-processing machine. That is, the stacking device 1 is capable of continuously performing a disposal process of disposing of an unwanted recording medium and a storage process of storing recording media to be stored, without stopping the device, as described previously.
When recording media which are stacked by the stacking device 1 according to the present embodiment are bound up into a booklet, images for first to last pages of one booklet are sequentially formed on a continuous medium and cut out by the image forming apparatus, and the pages are conveyed into the stacking device. Binding into a booklet can thus be realized.
As described previously, the image formation apparatus which forms images on the continuous medium 105 disposes of a part of the continuous recording medium 105 which remains at least on the conveyance path from the first recording section 1 at the first drum 130 to the cutter section 186, when image formation is started. The part of the continuous recording medium 105 to be disposed of is cut and ejected by the cutter section 186. Alternatively, however, a cutter blade 188a may be moved from a cutting position, and the long continuous recording medium 105 may be weaved through between rollers and disposed of, maintaining its length.
The stacking device according to the present embodiment can cause an unwanted recording medium to pass the retracted sheet contact section 31, convey a cut recording medium to the recording-media disposal section 5, and automatically dispose of the cut recording medium onto the disposal tray 20. Accordingly, workers need not carry out an operation of taking out unwanted recording media stored in the storage space.
Since the stacking device is provided below the cutter section, increase in installation area of the image forming apparatus including the stacking device can be restricted to a minimum, and size reduction is achieved.
According to the invention, there can be provided a stacking device which can perform high-speed processing and is small in size, and an image forming apparatus comprising the stacking device.
Number | Date | Country | Kind |
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2008-135895 | May 2008 | JP | national |
This is a Continuation Application of PCT Application No. PCT/JP2009/059549, riled May 25, 2009, which was published under PCT Article 21(2) in Japanese. This application is based upon and claims the benefit of priority from prior Japanese Patent Application No. 2008-135895, filed May 23, 2008, the entire contents of which are incorporated herein by reference.
Number | Date | Country | |
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Parent | PCT/JP2009/059549 | May 2009 | US |
Child | 12952439 | US |