JP2004189457A - Image recording device with sheet loading device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image recording device with sheet loading device responding to speeding-up and preventing misalignment of sheets after aligning the sheets. <P>SOLUTION: In the image recording device with sheet loading device, the sheet loading device has a tip holding means, a tip stopper, a sheet aligning part, and an elevating sheet discharge tray, which has an upper face detecting means. A projection member drive means and an upper face position detecting sensor constitute the upper face means. After the sheets are aligned by the sheet aligning part, an upper face of the sheet that is falling toward the elevating sheet delivery tray is knocked off downward by the projection member to promote the falling of the sheet and fix the fallen sheet, and the upper face of the loaded sheet is detected by the upper face detecting sensor to lift down the elevating sheet delivery tray to a predetermined position. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image recording apparatus including a paper stacking device used in, for example, a digital copying machine or a digital multifunction peripheral, and more particularly, to detecting an upper surface of a sheet discharged to a lifting sheet tray (elevation tray) provided in the sheet stacking apparatus. The present invention relates to an image recording apparatus provided with a sheet stacking device having a detecting unit (upper surface position detecting sensor) for detecting the position of a sheet.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as a sheet stacking device used as an accessory device of an image recording apparatus, a sheet tray (discharge tray) does not move up and down, a projection member is provided on a fixed sheet ejection side fence, and the projection member is made to protrude and retract. Things are often used.
[0003]
As an image recording apparatus equipped with a paper stacking device, for example, without raising and lowering the paper tray, providing a protruding member that can protrude and retract on the paper discharge side fence, hooking both ends of the paper on the protruding member, and lowering the posture when the paper falls There is known a device having a convex shape (see Patent Document 1).
[0004]
[Patent Document 1]
Japanese Patent Application Laid-Open No. Hei 9-124216
[Problems to be solved by the invention]
However, in the image recording apparatus including the sheet stacking device described in Patent Document 1, it is impossible to shift the sheet discharge tray (sheet tray), and when the stacking amount of sheets stacked on the sheet stacking device is increased, Since the paper discharge side fence is installed at the bottom of the paper tray, the distance over which the paper falls to the paper tray becomes long, and it is difficult to control the posture when the paper falls.
[0006]
SUMMARY OF THE INVENTION An object of the present invention is to provide an image recording apparatus provided with a sheet stacking device which can solve the above-mentioned problems, can cope with a high speed, and can prevent a sheet shift after alignment.
[0007]
[Means for Solving the Problems]
An object of the present invention is to provide an image recording apparatus including a sheet stacking device that transports ejected sheets one by one and stacks the sheets in a large amount in a horizontal state. A holding unit, a leading end stopper that regulates a leading end position of the sheet conveyed by the leading end holding unit, a sheet aligning unit that aligns the width direction of the sheet that comes into contact with the leading end stopper, and a position below the sheet aligning unit. And a vertically movable discharge tray configured to stack the sheets aligned by the sheet aligning unit in a horizontal state, and to be able to move up and down so that the upper surface of the stacked sheets is at a predetermined position. The sheet aligning unit is provided with upper surface detecting means for detecting an upper surface position of the paper stacked on the elevating paper discharge tray, and the upper surface detecting means strikes the paper conveying path from above to below. Can be dropped A projection member driving means for driving the projection member, and an upper surface position detection sensor for detecting the position of the projection member. After the paper is aligned by the paper alignment section, the projection member is The upper surface of the sheet falling toward the elevating sheet tray is knocked down, thereby facilitating the dropping of the sheet and fixing the sheet dropped on the elevating sheet tray. This is achieved by an image recording apparatus including a sheet stacking device, which detects an upper surface of stacked sheets and operates to lower the elevating sheet discharge tray to a predetermined position.
[0008]
According to the present invention having the above-described configuration, it is possible to shift the elevating sheet discharge tray (elevating tray) provided with the sheet stacking device, and hit the upper surface of the sheet when falling. The top surface is held down by the upper surface detection means even after the paper has fallen onto the elevating sheet discharge tray, while the upper surface of the loaded paper is being detected. Therefore, it is possible to provide an image recording apparatus including a sheet stacking device capable of preventing a sheet shift after alignment of stacked sheets.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described. Note that the description in this column does not limit the technical scope of the claims and the meaning of terms. Also, the following assertive description in the embodiment of the present invention indicates the best mode, and does not limit the meaning of the terms of the present invention or the technical scope.
[0010]
(1) FIG. 1 shows an example of an image recording apparatus to which the present invention is applied. FIG. 1 is an overall configuration diagram of an image recording apparatus including an image forming apparatus A and a sheet stacking apparatus B. Further, a sheet on which an image is formed in the image forming apparatus A and sent to the sheet stacking apparatus B is a recording sheet. Say.
[0011]
[Image forming apparatus]
The image forming apparatus A includes a charging unit 2, an image exposing unit (writing unit) 3, a developing unit 4, a transferring unit 5A, a discharging unit 5B, a separating claw 5C, and a cleaning unit 5D around the rotating image carrier 1. After the surface of the image carrier 1 is uniformly charged by the charging unit 2, an exposure scan based on image data read from a document by the laser beam of the image exposure unit 3 is performed. A latent image is formed, and the latent image is reversely developed by the developing unit 4 to form a toner image on the surface of the image carrier 1.
[0012]
On the other hand, the recording paper (paper) P supplied from the paper supply unit 6A is sent to the transfer position via the intermediate paper supply unit 6B. At the transfer position, the toner image is transferred onto the recording paper P by the transfer means 5A. Thereafter, the charge on the back surface of the recording paper P is erased by the charge removing means 5B, separated from the image carrier 1 by the separation claw 5C, transported by the transporting means 7A, and subsequently heated and fixed by the fixing means 8, and discharged by the discharging roller 7C. Is discharged by
[0013]
On the other hand, the surface of the image carrier 1 is cleaned by the cleaning unit 5D downstream of the separation claw 5C after the transfer to prepare for the next image formation.
[0014]
When image formation is performed on both sides of the recording paper P, the recording paper P heated and fixed by the fixing unit 8 is branched off from the normal discharge path by the transport path switching plate 7B, and is switched back by the reverse transport unit 7D. After being turned upside down, the sheet is discharged out of the apparatus by the discharge roller 7C with the toner surface (image surface) facing down. The recording paper P discharged from the paper discharge roller 7C is sent to the entrance 10 of the paper stacking device B.
[0015]
The sheet stacking device B is provided with a sheet transport unit 20, a sheet aligning unit 100, and a lifting sheet tray (elevation tray) 200 as a sheet stacking unit, which will be described in detail later.
[0016]
The recording paper P conveyed from the image forming apparatus A to the entrance 10 of the paper loading device B is subjected to a paper loading process described later near the transport path HLa, and the recording paper P that has completed the paper loading process is a paper. The sheet is discharged to the elevating sheet discharge tray (elevating tray) 200 of the loading device B.
[0017]
(2) Configuration of the Paper Loading Device Provided in the Image Recording Apparatus The paper loading process will be described with reference to FIG. 2 or FIG. 2 is a sectional view of a main part of the sheet stacking device, and FIG. 3 is a top view of FIG.
[0018]
[Paper loading device]
As shown in FIG. 2 or FIG. 3, the paper stacking device B is provided with a paper transport unit 20 having a leading end holding member 102 as a leading end holding unit, a paper aligning unit 100, and an elevating discharge tray (elevating tray) 200. The recording paper (paper) P conveyed from the image forming apparatus A is subjected to a paper stacking process, which will be described later, by the paper transport unit 20 having the leading end holding member 102, the paper alignment unit 100, and the elevating tray 200.
[0019]
The recording paper P that has been subjected to the paper loading process in the paper loading device B is discharged to the lifting tray 200 of the paper loading device B and loaded. The elevating tray 200 on which the recording paper P (or the paper bundle T) is loaded is lowered to a predetermined position by detecting the position of an upper surface position detecting sensor using an interrupter switch ISw, for example. Further, the sheet conveying section 20 is provided with a leading end holding member 102 as leading end holding means. Further, an upper surface detecting unit 130 is provided on the downstream side of the transport path HLa and on the upstream side of the front end stopper 101.
[0020]
As shown in FIG. 2, the paper transport unit 20 extends from the entrance 10 to the internal discharge roller DRa including a pair of roller members, and the paper transport unit 20 includes a main body of the image recording apparatus. A pair of transport rollers HRa immediately after the entrance 10 for transporting the recording paper (paper) P discharged from the image forming apparatus A), and the leading end of the recording paper P when passing through the paper transport unit 20 is placed on the transport path HLa. A tip holding member 102 as tip holding means for holding is arranged. The tip holding member 102 is attached to a belt Ba driven by a drive motor (not shown). The tip holding member 102 is provided with a spring SPa for holding the recording paper P while holding it. Further, a sensor Sa for detecting the passage timing of the recording paper P is provided between the transport roller HRa and the internal discharge roller DRa.
[0021]
-Paper Alignment Unit As shown in FIG. 2, the paper alignment unit 100 is provided with a transport path HLa from the internal discharge roller DRa to the leading end stopper 101. Further, the sheet aligning unit 100 includes a leading end stopper 101 that regulates a leading end position of the recording sheet P held and conveyed by the leading end holding member 102, left and right sheet aligning plates 110A and 110B that perform widthwise alignment, and A reference plate 103 is provided on the rear end side (immediately after the internal discharge roller DRa) of the recording paper P on the transport path HLa in the transport direction for performing alignment in the transport direction. The sheet aligning section 100 is provided with a belt Ba, which is driven by a drive motor (not shown), and a belt Bb on both sides of the belt Ba. The front end stoppers 101 are fixedly attached to the belts Bb by fusion.
[0022]
Further, as shown in FIG. 3, the sheet aligning plate 110A is supported by a timing belt TBa that can move in a direction perpendicular to the sheet discharging direction via a pulley PLa that is driven to rotate, and a shaft held by a bearing JTa. It slides using Ja and the shaft Jb held by the bearings JTb and JTc as guides. The timing belt TBa is driven and rotated by a timing belt drive motor Ma. Further, the sheet aligning plate 110B is supported by a timing belt TBb capable of moving in a direction perpendicular to the sheet discharging direction via a driven pulley PLb, and is also supported by a shaft Ja held by a bearing JTa and bearings JTb, JTc. Is slid with the shaft Jb held at the guide as a guide. The timing belt TBb is driven and rotated by a timing belt drive motor Mb.
[0023]
・ Elevating paper tray (elevating tray)
As shown in FIG. 2, the elevating sheet discharge tray (elevating tray) 200 includes a sheet table 202, a sheet stacking unit 201 to which the sheet table 202 can be attached and detached, and an elevating tray driving motor Mc. The elevating discharge tray (elevation tray) 200 horizontally loads the recording paper (paper) P below the paper alignment unit 100. The elevating tray 200 is configured to be able to move up and down by an elevating tray drive motor Mc, and is controlled so that the upper surface position of the recording paper P stacked on the elevating tray 200 is constant (predetermined position) as described later.
[0024]
As shown in FIG. 2 or FIG. 3, the upper surface detecting unit 130 is disposed on the paper aligning unit 100, and includes a protrusion member 131 as an upper surface detecting member, a solenoid SD used as an upper surface detecting driving unit, It is constituted by, for example, an interrupter switch ISw used as an upper surface position detection sensor for detecting the position of the projection member 131. The projection member 131 is integrally fixed to and attached to the rotation axis Jt, and an actuator ACa which is also integrally fixed to the rotation axis Jt is provided at one end (the lower side in FIG. 3) of the rotation axis Jt. Can be The rotation shaft Jt is urged downward by the force of the coil spring SPb, and the protrusion member 131 and the actuator ACa are integrally rotated by the on-off of the solenoid SD. That is, by the on-off of the solenoid SD, the rotation axis Jt to which the projection member 131 and the actuator ACa are attached is rotated, and the actuator ACa attached to the rotation axis Jt and the projection member 131 are rotated about the rotation axis Jt as the rotation center. You. Further, the interrupter switch ISw as the upper surface position detection sensor is turned on and off by the shielding of the actuator ACa. In the on state of the solenoid SD, the rotation axis Jt is rotated in the counterclockwise direction indicated by the arrow in FIG. 2, and the protrusion member 131 is maintained at the raised position indicated by the solid line. Normally, the solenoid SD is turned on. When the recording paper P is carried in and the solenoid SD is turned off, the rotating shaft Jt is rotated by the coil spring SPb and its own weight. The detection light of the interrupter switch ISw is cut off by the operation of the actuator ACa fixed to the rotation axis Jt, and the stacking amount of the recording paper P (or the paper bundle T) is detected by the interrupter switch ISw. When the solenoid SD is turned off, the protrusion member 131 rotates in the direction of the arrow shown in FIG. 4, and conveys the upper surface of the recording paper P carried into the paper path (no symbol) on the lower surface of the belts Ba and Bb. The sheet is knocked down from above the path HLa downward, and is stacked on the elevating tray 200 so as to press the recording paper P. The elevating tray 200 on which the recording paper P (or the sheet bundle T) is loaded, the interrupter switch ISw as an upper surface position detection sensor is turned on by an actuator ACa rotated by, for example, on-off of a solenoid SD as a projection member driving means. It is lowered to a predetermined position based on the detection information of the interrupt switch ISw which is turned off and on.
[0025]
(3) The sheet stacking processing operation of the sheet stacking apparatus will be described below with reference to FIG. 4 and FIGS. 2 and 3 described above. FIG. 4 is a perspective view showing the upper surface detecting means.
[0026]
1 Recording paper (paper) P is discharged from the main body of the image recording apparatus (image forming apparatus A).
[0027]
2 The recording paper P is transported from the entrance 10 of the paper stacking device B through the paper transport unit 20, and the leading end of the recording paper P reaches the paper alignment unit 100.
[0028]
(3) Waiting at the exit side of the internal paper discharge roller DRa in the transport direction of the recording paper P, the tip position is held by the tip holding member 102 as tip holding means attached to the belt Ba, and the lower side of the belts Ba and Bb. The recording paper P is carried into the paper path (see FIG. 2, no symbol). That is, when the leading end holding member 102 is waiting at the exit side of the internal discharge roller DRa and the leading end of the recording paper P entering from the entrance 10 has cut off the sensor Sa and a predetermined time has elapsed, the leading end holding member 102 Is started, the speed starts from zero and accelerates, and when the tip holding member 102 reaches the normal speed, the recording paper P is sandwiched between the spring SPa and the belt Ba.
[0029]
Specifically, the transport roller HRa and the inner discharge roller DRa rotate at a constant speed and at the same normal speed as the copy speed, transport the recording paper P, and transport the recording paper P through the paper transport unit 20. The belt Ba is rotated out before the leading end of the inner discharge roller DRa is engaged with the inner discharge roller DRa, and the front end holding member 102 waiting at the exit side of the inner discharge roller DRa is accelerated at a certain timing, and FIG. The leading edge of the recording paper P catches up with the leading end holding member 102 moved by the belt Ba before the leading end holding member 102 reaches the leading end stopper 101 after being moved out in the direction indicated by the arrow of FIG. When the belt Ba to which is attached and the leading end of the recording paper P fed by the in-body discharge roller DRa have reached a constant speed (normal speed), the belt Ba is moved between the spring SPa of the leading end holding member 102 and the belt Ba. The recording paper P is incorporated in addition. The recording sheet P is conveyed to the position of the leading end stopper 101 in a state where the leading end of the recording sheet P is held by the spring SPa of the leading end holding member 102 and the belt Ba.
[0030]
The front end stoppers 101 provided on the belts Bb on both sides of the belt Ba wait at different fixed positions depending on the size of the paper (recording paper) P. After the recording paper P hits the front end stopper 101, the front end holding member 102 is moved together with the belt Ba rotated clockwise.
[0031]
(4) The recording paper P, which has stopped against the front end stopper 101, comes off the spring SPa of the front end holding member 102, and the recording paper P starts to fall by its own weight.
[0032]
5. At this time, the left and right (both ends) sheet aligning plates 110A and 110B are shifted in the width direction of the recording sheet P (the conveying direction of the recording sheet P), and are shifted by the left and right (both ends) sheet aligning plates 110A and 110B. The recording paper P to be freely dropped is aligned in the width direction. Shifting of the recording sheet P in the width direction by the sheet alignment plates 110A and 110B is performed for each print in units of one to several copies, or ten to several tens copies. Further, the recording paper P is aligned at the left and right positions with respect to the center of the recording paper P conveyed to the paper alignment unit 100. The alignment of the recording paper P by shifting the left and right (both ends) of the paper alignment plates 110A and 110B to the left and right in the width direction of the recording paper P is, for example, 15 mm to the right from the center and 15 mm to the opposite side (left). The recording paper P is alternately shifted by 30 mm on the left and right sides, and the recording paper P is aligned.
[0033]
6 After the alignment of the recording paper P by the paper alignment plates 110A and 110B in the paper alignment unit 100, and during or after the recording paper P is falling, the belt Bb to which the leading end stopper 101 is attached is moved to the recording paper P. The rear end of P is instantaneously moved in the counterclockwise direction toward the reference plate 103, and the rear end of the recording paper P is moved in the counterclockwise direction toward the reference plate 103. The recording paper P is moved in the free direction, and the recording paper P is aligned in the transport direction.
[0034]
7. The protrusion member 131 is moved from above the sheet aligning section 100 toward the upper surface of the stacked sheets of the lifting tray 200 below.
[0035]
8 The projection member 131 hits the upper surface of the falling recording paper P to promote the falling. Specifically, the projection member 131 of the upper surface detecting means 130 moves from the retreat position above the transport path HLa toward the falling recording paper P below, and hits the upper surface of the recording paper P. The falling of the recording paper P is promoted, and the recording paper P and the projection member 131 reach the upper surface of the lifting tray 200 on which the recording paper P is loaded. The protruding member 131 keeps pressing the upper surface of the stacking paper on the elevating tray 200 for a predetermined time to prevent the recording paper P from shifting.
[0036]
9. The protrusion member 131 on the upper surface of the recording paper P by its own weight and the spring load reaches the upper surface of the lifting tray 200 on which the recording paper P is loaded, and holds the upper surface of the recording paper P for a predetermined time while detecting the upper surface. The upper surface position of the recording paper P is detected by the means 130. That is, the position of the projection member 131 is detected by the interrupter switch ISw while the projection member 131 is pressing the upper surface of the recording paper P, and the lifting tray 200 is lowered to a predetermined position (the upper surface position of the recording paper P is fixed). Is controlled so that it becomes).
[0037]
Specifically, as shown in FIG. 4, the actuator ACa is fixed to one end of the rotation shaft Jt by a screw Na. As described above, the solenoid SD (see FIG. 2, not shown in FIG. 4) is turned off, and the actuator ACa is first rotated about the rotation axis Jt in the direction shown by the arrow (when the actuator ACa falls down). )) The actuator ACa turns off the interrupter switch ISw and turns off the interrupter switch ISw. The actuator ACa shuts off the interrupter switch ISw, and the state of the interrupter switch ISw is observed several milliseconds after the interrupter switch ISw is turned off. That is, at the time of detecting the upper surface, the solenoid SD (see FIG. 2, not shown in FIG. 4) is turned off, the upper surface of the recording paper P is knocked down by the projection member 131, and the state of the interrupter switch ISw is observed. When the end (upper side in FIG. 4) of the actuator ACa is higher than the interrupting position of the interrupter switch ISw, the actuator ACa is turned off even if the actuator ACa is dropped with the solenoid SD turned off. Since it is determined that a predetermined number of recording sheets P are stacked on the elevating tray 200 in the blocking position, the elevating tray 200 is operated to be lowered by the elevating tray drive motor Mc. That is, the rotation of the lifting / lowering tray drive motor Mc rotates the movable member pulley (without reference numeral), and the rotation of the movable member wire (without reference numeral) lowers the paper stacking means 201 to which the paper base 202 is attached. When the projecting member 131 is lowered by the lowering operation of the lifting tray 200, the actuator ACa is also lowered in the direction of the arrow, the actuator ACa is disengaged from the interrupter switch ISw, and the interrupter switch ISw is turned on. The position where the interrupter switch ISw is turned on is a predetermined position where the elevating tray 200 is lowered for each print. As described above, one print is a unit of one to several copies, or ten to several tens copies.
[0038]
10. As described above, the elevating tray 200 is lowered until the upper surface of the stack of the recording paper P reaches the predetermined position.
[0039]
11 The solenoid SD is turned on again, and the protruding member 131 is moved to the retracted position (see FIG. 2, not shown in FIG. 4).
[0040]
12. The next recording paper (paper) P is discharged from the main body (image forming apparatus A) of the image recording apparatus and is carried into the paper stacking apparatus B.
[0041]
In the above description, hitting of the recording paper P by the projection member 131 is performed for each copy (one copy), and control of the lowering operation of the lifting tray 200 is performed for each print.
[0042]
As described above, by adopting the configuration of the present invention, the sheet can be shifted on the elevating sheet discharge tray (elevating tray) provided in the sheet stacking device. The processing time can be spared, the speed can be increased, and the upper surface detecting means can detect the upper surface of the stacked paper even after the paper has fallen on the elevating discharge tray. Since the upper surface of the sheet is pressed, an image recording apparatus including a sheet stacking device capable of preventing a sheet shift after alignment of stacked sheets is obtained.
[0043]
In addition, in addition to the above-described sheet stacking device, a post-processing device such as a punching process, a binding process, a punching process, and a folding process can be used by being connected between the image forming apparatus and the sheet stacking device.
[0044]
【The invention's effect】
According to the present invention, the sheet can be shifted by the sheet alignment plate provided in the sheet transport unit of the sheet stacking device, and the upper surface of the sheet is hit at the time of drop. Since the upper surface of the loaded paper is pressed while the upper surface of the loaded paper is being detected by the upper surface detecting means even after the paper is dropped on the elevating discharge tray, It has become possible to provide an image recording apparatus including a sheet stacking device capable of preventing a sheet shift after alignment.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating a main part of an embodiment of an image recording apparatus according to the present invention.
FIG. 2 is a sectional view of a main part of the paper stacking device.
FIG. 3 is a top view of FIG. 2;
FIG. 4 is a perspective view showing an upper surface detecting unit.
[Explanation of symbols]
Reference Signs List 10 entrance section 20 sheet transport section 100 sheet aligning section 101 leading end stopper 102 leading end holding member 103 reference plates 110A, 110B sheet aligning plate 130 upper surface detecting means 131 projecting member 200 elevating paper tray (elevating tray)
201 sheet stacking means 202 sheet tray A image forming apparatus B sheet stacking apparatus ACa actuator Ba, Bb belt DRa internal discharge roller HLa transport path ISw interrupter switch Mc elevating tray drive motor SD solenoid SPa spring SPb coil spring P recording paper (paper)
T paper bundle

Claims (1)

In an image recording apparatus including a sheet stacking device that conveys ejected sheets one by one and stacks the sheets in a horizontal state in a large amount,
Leading edge holding means for holding and transporting the leading edge of the paper being discharged
A leading end stopper for regulating the leading end position of the sheet conveyed by the leading end holding means,
A sheet aligning unit that aligns the width direction of the sheet falling in contact with the leading end stopper,
An elevating sheet tray, which is installed below the sheet aligning section and stacks the sheets aligned by the sheet aligning section in a horizontal state, and is configured to be able to move up and down so that the upper surface of the stacked sheets is at a predetermined position; ,
Is provided in the paper loading device,
An upper surface detecting unit that detects an upper surface position of the paper stacked on the elevating discharge tray is installed in the paper alignment unit,
The upper surface detection unit includes a protrusion member that can be knocked down from above the paper transport path and a protrusion member driving unit that drives the protrusion member, and an upper surface position detection sensor that detects a position of the protrusion member. Composed of
After the paper is aligned by the paper aligning unit, the projecting member knocks down the upper surface of the falling paper toward the elevating discharge tray, thereby promoting the falling of the paper and raising and lowering the discharge tray. An image provided with a paper stacking device, wherein the paper dropped on the paper is fixed, the upper surface position detection sensor detects the upper surface of the stacked paper, and operates to lower the elevating discharge tray to a predetermined position. Recording device.

Images