JPH09202463A - Paper feed device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To feed the paper from a first paper storage part even when a transfer means is not returned to a second paper storage pail side, or even in a returning process when the copying sheet is transferred to the first paper storage part from the second paper storage part by the transfer means. SOLUTION: A first paper loading part 25 of a first paper storage part and a second paper loading part 26 of a second paper storage part are formed of serrated shape to be engaged with each other. When a paper transfer means 20 moves the second paper loading part horizontally to the first paper storage part, an upper surface of the second paper loading part is higher than an upper surface of the first paper loading part. On the other hand, when the paper transfer means transfers the paper which is loaded by lowering the second paper loading part on the first paper loading part, and when the paper transfer means is returned to the second paper storage part, a paper loading surface of the second paper loading part is lower than a paper loading surface of the first paper loading part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding device provided in an image forming apparatus such as a copying machine, a printer or a facsimile machine, and more particularly to an image forming apparatus in which two sheet accommodating portions are arranged side by side in a lateral direction. The present invention relates to a paper feeding device that has effects such as reducing a loss time due to a moving time of a paper transfer unit that moves back and forth between two paper accommodating units, and preventing erroneous setting of paper.

[0002]

2. Description of the Related Art In image forming apparatuses such as copying machines, printers, and facsimile machines, recently, from the viewpoint of space saving, a paper accommodating portion such as a paper feed tray is built into the main body of the apparatus, and the front surface of the main body of the apparatus is reduced. A so-called front loading type device in which a paper storage portion is freely drawn out from the side is widely used. Further, in this type of image forming apparatus, a tandem type sheet feeding device in which sheet accommodating portions are arranged in parallel in the lateral direction has been recently developed in order to further save space. As one of the methods, when there is no more paper in the first sheet storage section, the sheet bundle stored in the adjacent second sheet storage section is collectively moved into the first storage section. Examples of such a tandem-type sheet feeding device include those disclosed in JP-A-3-195639 (Cannon) and JP-A-6-144600 (Ricoh). In the former case, when it is detected that there is no sheet in the first sheet storage portion provided with the sheet feeding means and that the sheets are stacked in the adjacent second sheet storage portion, it is automatically By collectively moving the sheet bundle stored in the second sheet storage unit to the first sheet storage unit, it is possible to save the trouble of stopping the copying operation and supplying sheets. The latter is a lock mechanism that prohibits the pulling-out of the second sheet storage unit out of the machine during the paper feeding operation from the first sheet storage unit, while allowing the both storage units to be pulled out during the non-paper feeding operation. It is equipped with.

[0003]

However, in these conventional sheet feeding methods, the sheet transfer means for collectively moving the copy sheet bundle in the second sheet accommodating section into the first sheet accommodating section is provided. While the reciprocating operation is being performed, the sheet feeding operation of the sheet feeding means provided in the first sheet accommodating portion is stopped, which causes a problem that productivity is reduced. Further, if the second sheet storage unit is pulled out when the sheet transfer unit is not in a fixed position, such as when the sheet transfer unit is moving, the sheet is moved to the wrong position on the second sheet storage unit where the sheet phase shifting unit does not exist. Could be loaded, which was a problem. Also, if the drawer of the paper storage unit is opened when the paper transporting means is not in an appropriate position, an erroneous setting will occur, so it is necessary to lock the drawer, but if the lock mechanism is operated using a solenoid or the like, This is a problem because the cost is high.

The present invention has been made in view of the above, and the invention of claim 1 is one in which when the copy sheet is transferred from the second sheet storage section to the first sheet storage section by the transfer means,
An object of the present invention is to provide a configuration in which the sheet can be fed from the first sheet storage section even when the transfer means does not return to the second sheet storage section side or in the process of returning. According to the second aspect of the present invention, it is possible to reduce a paper feeding loss time due to a moving time required for the second sheet stacking section configured to be movable back and forth between the two sheet storage sections to reciprocate between the two sheet storage sections. It is an object. According to the third aspect of the present invention, even when the second sheet stacking section configured to be able to move back and forth between the two storage sections is inside the first sheet storage section, the transfer means is used when the second sheet storage section is pulled out from the apparatus main body. Is always returned to the fixed position, and the purpose is to prevent incorrect setting of paper. According to the invention of claim 4, when the second sheet stacking unit is not in a fixed position in the second sheet stacking unit, it is impossible to pull out the second sheet storage unit from the apparatus main body to prevent erroneous setting. There is.

A fifth aspect of the present invention is intended to reduce the cost by causing the operation of the lock mechanism for locking the drawer of the sheet accommodating section to operate in conjunction with the transfer means without using a solenoid or the like. I am trying.

[0006]

In order to achieve the above object, the invention of claim 1 is such that a first sheet accommodating portion for accommodating a plurality of sheets and a sheet in the first sheet accommodating portion from the bottom to the first. A sheet feeding unit for feeding the sheets one by one, a second sheet accommodating section arranged in parallel in the lateral direction of the first sheet accommodating section, and sheets in the second sheet accommodating section are collectively contained in the first sheet accommodating section. A sheet feeding device having a sheet transporting unit for transporting the sheet;
The sheet stacking section and the second sheet stacking section of the second sheet storage section are formed in a comb-teeth shape that meshes with each other, and the second sheet stacking section is moved to the first sheet storage section for transfer by the sheet transfer means. When the sheet is horizontally moved to the side, the upper surface of the second sheet stacking unit is located higher than the upper surface of the first sheet stacking unit, and the sheet transporting means lowers the second sheet stacking unit to stack the stacked sheets into the first sheet stacking unit. The sheet stacking surface of the second sheet stacking unit is set to the first sheet stacking unit when the sheet is transferred to the second stacking unit and when the sheet transporting unit returns to the second sheet storing unit.
It is characterized in that it is lower than the sheet stacking surface of the sheet stacking section. According to a second aspect of the present invention, the first sheet accommodating portion is provided with a sheet presence detecting unit that detects the presence or absence of a sheet, and a paper near-end detecting unit that detects a small remaining amount of the sheet. When the near end is detected, the second sheet stacking unit is raised until the height of the sheet stacking surface of the second sheet stacking unit is higher than the upper surface of the sheet in the first sheet storage unit, and then the second sheet stacking unit is set to the above-mentioned state. It is characterized in that it is moved to the side of the first sheet accommodating section by the sheet conveying means and is made to stand by in the first sheet accommodating section after the movement is completed. According to a third aspect of the present invention, a drawer switch is provided in the drawer section that supports the second sheet storage section, and when the sheets in the first sheet storage section are near end, the second sheet stacking section is in the first sheet storage section. When the drawer switch is pressed in the standby state, the paper transfer means moves the second paper stacking unit to the second paper storage unit. According to a fourth aspect of the present invention, the second sheet storage section cannot be pulled out from the apparatus main body when the second sheet storage section is inside the first sheet storage section or is moving. . According to a fifth aspect of the present invention, the second accommodating portion and the apparatus main body are provided with a lock means for preventing the second accommodating portion from being pulled out. It is characterized by being released by stopping at a fixed position.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The sheet feeding device of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a schematic diagram of the entire configuration of an example of an image forming apparatus to which the paper feeding device of the present invention is applied, FIG. 2 is a perspective view showing a drawn-out state of a paper feeding unit, and FIGS. FIGS. 4 (a) and 4 (b) are front and bottom views showing the structure and operation of the transfer means, and FIGS. 5 (a) and 5 (b).
6C and 6C are configuration explanatory views of a stacking unit lifting mechanism. This image forming apparatus has an image forming apparatus main body 1 and an automatic document feeder 2 mounted on the main body 1. The image forming apparatus main body 1 includes a reading optical system 3 and an electrophotographic type device. Image part 4,
It is composed of a sheet feeding device 5. The characteristic configuration of the present invention exists in the sheet feeding device 5. The specific configurations and operations of the automatic document feeder 2, the reading optical system 3, and the image forming unit 4 are well known, and therefore their explanations are omitted. The sheet feeding device 5 includes two sheet accommodating units 11 and 12 arranged side by side in the lateral direction.
And a copy sheet P taken out from the lowermost part of the first sheet storage section 11 by the sheet feeding section 13
Passes through the conveyance path 14 and then the registration roller 15 of the image forming unit 4.
The toner image is supplied to the transfer position 17 around the photoconductor 16, is transferred by the toner image on the photoconductor, is further fixed by the fixing device 18, and is discharged to the outside of the apparatus.

<Structure of Embodiment> Next, the structure of the sheet feeding device of the present invention will be described. First, the sheet feeding device 5 according to the first embodiment of the present invention is roughly classified into a first sheet storage section 11, a second sheet storage section 12 arranged in parallel with the first sheet storage section 12, and a sheet feed section 12. Means 13, Paper Transfer Means 20, Stacking Section Lifting Mechanism 2
And 1. As shown in FIG. 2, each of the sheet accommodating portions 11 and 12 is supported by a drawer portion 22 that is supported so as to be freely drawn in and out of the apparatus from the front surface of the apparatus body.
When 2 is mounted in the main body of the apparatus, sheet feeding can be performed by the sheet feeding means 13, and when it is pulled out, sheets can be replenished to the sheet storage unit. In this embodiment, the drawer section 22 is connected to the second sheet storage section 12, and by pulling out the drawer section 22, only the second sheet storage section 12 is pulled out. The first sheet storage unit 11 may also be drawn out. Each of the sheet accommodating sections 11 and 12 has a first sheet stacking section 25 and a second sheet stacking section 26 for stacking a sheet stack, respectively.
A back plate 26b stands upright from the rear edge (left edge). Each of the sheet stacking surfaces 25a and 26a is formed in a comb tooth shape whose positions are shifted so as to mesh with each other.

FIG. 3 shows a second embodiment of the present invention. As shown in FIG. 3, in the first paper accommodating portion 11, whether or not the paper P1 is on the comb-shaped paper stacking surface 25a. A paper presence detecting means 30 for detecting the presence or absence of the sheet, and a paper near-end detecting means 31 for detecting the remaining amount of the paper on the paper stacking surface 25a (whether or not the top surface of the paper is at a certain height position). Have. The paper presence detection unit 30 is arranged immediately below the paper placing surface 25a so as to detect the presence or absence of the paper located immediately above the gap between the comb teeth of the paper placing surface 25a. Paper near end detection means 31
Is placed at an appropriate position so that the upper surface of the paper P1 can be detected when the stacking amount of the paper P1 is reduced to the near end position, as shown in FIG. 3 (a). As the detection means 30 and 31, for example, light reflection type photo interrupters are used. A paper presence detecting means 32 for detecting the presence / absence of a sheet on the second sheet accommodating section 12 is also arranged at an appropriate position on the second sheet accommodating section 12.

The sheet transfer means 20 is composed of a bottom plate 36a and an upright plate 36b, and includes a carriage 36 which is an L-shaped plate having movable means such as wheels 35 on the bottom surface of the bottom plate 36a, a belt, a pulley and the like. The second sheet stacking unit lifting mechanism 21 includes the trolley moving means 37 and the erection plate 36 of the trolley 36.
It is attached to b. As shown in FIG. 5, a vertical plate 36b of the truck is formed with a slit 36b-1 extending in the vertical direction, and two shafts 26b-1 projecting from the back surface of the second sheet stacking unit 26 are free to play in this slit. It is arranged in a fitted state and slides up and down. An L-shaped height detection shield plate 40 is horizontally projected rearward at a proper position between the shafts 26b-1, and the height detection shield plate 40 is a standing plate 36b of the truck.
It is movably supported in the opening 36b-2.

On the back surface of the standing plate 36b of the carriage 36, there is a second
Sheet stacking unit driving means 41 (eg stepping motor)
And a pair of pulleys 42 driven by the second sheet stacking unit driving means 41 and arranged in a vertical positional relationship, and each pulley 4
There is a belt 43 that is stretched over 2, and the belt 43 and the height detection shield plate 40 on the second sheet stacking unit 26 are integrally fixed by screws or the like. Therefore, when the belt 43 stretched around the pulley 42 is rotated forward and backward by the output of the driving unit 41, the detection shield plate 40 integrated with the belt 43, that is, the second sheet stacking unit 26 moves up and down together. The tip of the height detection shield plate 40 is bent in an L shape, and when the height detection shield plate 40 moves up and down, the upper limit detection means 45 and the lower limit detection means 46 arranged in a vertical position on the standing plate 36b. Is configured to be detected by. That is, the carriage 36 is provided with an upper limit detecting means 45 for detecting the upper limit height of the height detecting and shielding plate 40 and a lower limit detecting means 46 for detecting the lower limit, and these detecting means are constituted by, for example, a transmissive photo interrupter. .

The carriage moving means 37 is a carriage driving means 50.
(For example, a stepping motor), a pulley 51a fixed to the output shaft of the carriage driving means 50, and the other pulley 51.
4b and a belt (timing belt) 52 stretched over both pulleys. The belt 52 and the carriage 36 are integrally attached by a belt attachment member 53 as shown in FIG. 4 (b). The belt mounting member 53 is configured by a member having unevenness that fits into the unevenness of the belt 52, a screw, or the like. The carriage moving means 37 is installed on the base 55, and the wheels 35 also move on the base 55. In addition, a bogie position detection shield plate 54 is bent downward at a proper position (a corner portion in this example) of the bottom plate 36a of the bogie 36, and a bogie position detection shield is formed on the base 55. Home position detecting means 55 for detecting the home position of the carriage 36 and movement position detecting means 56 for detecting the movement position of the carriage 36 are provided along the movement path of the plate 54. It is preferable that any of the detection means is composed of a transmissive photo interrupter, a limit switch, and other sensors.

Further, in the third embodiment of the present invention, as shown in FIG. 1, there is a drawer switch 60 at an appropriate position on the front surface of the drawer section 22, and when the drawer section 22 is pulled out, the switch 60 is always used. The second sheet stacking unit is configured to return to a fixed position in the second sheet storage unit when pushed.
Such an operation is realized by the control unit 70 shown in FIG. 7 by a signal from the switch 60. Also,
In the fourth embodiment, as shown in FIG. 6, the shaft portion 62a is connected to the drawer portion 2 through the opening 61 provided on one side surface of the drawer portion 22.
The distal end of the pullout stopper 62 pivotally supported at a proper position in 2 is projected and inserted. The pull-out stopper 62 is constantly urged by the spring 63 to the position shown by the solid line in FIG. Further, at a position on the apparatus main body 1 side facing the pull-out stopper 62, the pull-out portion 2 projects forward of the tip end portion 62a of the pull-out stopper 62 at the solid line position.
Stopper contact portion 65 for preventing the pulling out 2
Are protruded integrally. This drawer stopper 62
As shown in the figure, the inner end portion 62b of the carriage is bent downward. When the carriage 36 moves in the direction of the arrow in FIG. It is configured to be rotated. When the drawer stopper 62 is at the dotted line position, there is no interference with the stopper abutting portion 65, so that the drawer portion 22 can be pulled out forward.

<Operation of Form Example> FIG. 8 is a flow chart showing the operation of the form example corresponding to claim 1. Normally, as shown in FIG. 1, the sheets P are placed on the first and second sheet stacking units 25 and 26.
The sheet feeding operation is performed in a state where 1 and P2 are stacked, and the presence of sheets on both stacking sections 25 and 26 is detected by detecting means 30 and 32 including a reflection type photo interrupter and the like, respectively. At this time, the height of the second sheet stacking unit 26 is set to the upper position by detecting the height detection shield plate 40 by the upper limit detection unit 45 (FIG. 1). The sheets on the first sheet stacking unit 25 are exhausted, and the control unit (CPU, ROM, RAM, etc.) is activated by a detection signal from the sheet presence detection unit 30.
When the control unit 70 determines that there is no paper, the control unit 70 drives the carriage driving unit 50 to move the second paper stacking unit 26 together with the carriage 36 to the first paper storage unit 11, and the moving position detection unit 56 detects the position. When this is done, stop this (ST1,
2, 3, 4). Subsequently, the second sheet stacking unit driving means 41 is driven to lower the second sheet stacking section 26 to a position where the height detection shield plate 40 is detected by the lower limit detection section 46 (ST5, 6, 7, 8). At this lower limit position, the stacking surface 26a of the second sheet stacking section 26 is set to a position lower than the stacking surface 25a of the first sheet stacking section 25, so that the comb-like stacking surface 26a is formed. Comb-shaped loading surface 25
When the sheet P2 passes the sheet a and moves downward, the sheet P2 is delivered onto the stacking surface 25a. After that, the carriage 36 returns to the position detected by the home position detecting means 55 by the reverse rotation of the driving means 50, and the height of the second sheet stacking section 26 moves to the upper limit position again (ST9, 10, 11, 12). ,
13, 14). According to this first embodiment, after transfer,
Since the paper can be fed by the paper feeding means 13 even while the second paper stacking unit 26 is returning from the first paper accommodating unit 11 side to the second paper accommodating unit 12 side, the productivity can be improved. .

Next, FIG. 9 is an operation flow of another embodiment (second embodiment) of the present invention shown in FIG. 3, and corresponds to claim 2. The paper near-end detection unit 31 detects that the amount of the paper P1 on the first paper stacking unit 25 is a certain amount (for example, 50 sheets) or less, and the presence of the paper on the second paper stacking unit 26 is detected by the detection unit. When detected by 32, the control unit 70 moves the carriage 36 located on the second sheet storage unit 12 side to the first sheet storage unit 11 side as in the case of the above embodiment (see FIG. a)), moving position detecting means 5
It is stopped at the detection position of 6 (ST20-24). Then, while the paper presence detection means 30 is detecting the remaining paper P1, the paper feed detection means 30 keeps the standby state, and the paper feeding means 13 performs the paper feeding as usual. At this time, the upper limit detection position (height) of the upper limit detection unit 45 is set so that the lower surface of the stacking surface 26a of the second sheet stacking unit 26 is located above the upper surface position of the sheet when the near end detection unit 31 detects the near end. If set to, the problem of erroneous detection by the paper near-end detection means 31 does not occur. When the sheets on the first sheet stacking unit 25 are exhausted, the stacking surface 26a of the second sheet stacking unit 26 is lowered below the stacking surface 25a of the first sheet stacking unit 25, as in the first embodiment. Transfer the paper (ST2
4 to 28), and thereafter, the carriage 36 and the emptied second sheet stacking unit 26 are returned to the position detected by the home position detecting unit 55 by the reverse rotation of the driving unit 50, and the height of the second sheet stacking unit 26 is increased. Again to the upper limit position (ST
29-34). In this example, when the sheets on the first sheet stacking unit 25 reach the near end, the second sheet stacking unit 2
Since 6 moves to the first sheet stacking unit 25 and starts waiting for transfer, the time required for the sheet transporting unit 20 to move from the second sheet stacking unit to the first sheet stacking unit (paper feed standby time). Can be shortened, and the productivity can be further improved.

Next, FIG. 10 is a flowchart showing the operation of the third embodiment of the present invention, and corresponds to claim 3. In this embodiment, the pull-out switch 60 is, for example, a push switch, and when a signal output by turning on the switch 60 is input by the control unit 70,
In the control unit 70, the carriage 36 and the second sheet stacking unit 26 are connected to each other.
When it is not in the home position, it is left as it is, and when it is not in the home position, it is moved to the home position by cooperation of the carriage driving means 50 and the home position detecting means 55 (ST40 to 44). In other words, this drawer switch 60
Is a switch that is turned on when the drawer unit 22 is pulled out. If the switch 60 is not turned on, the carriage 36
And the like may be located on the side of the first accommodating portion 11, and if the drawer portion 22 is pulled out in this state, the second paper stacking portion 26
The second sheet storage section 1 with the sheet not being in the second sheet storage section 12.
Since 2 is pulled out toward the front, there is a risk that sheets may be erroneously set in the second sheet accommodating section 12 where the second sheet stacking section 26 does not exist. When you pull it out, the second storage unit 1
Since the second sheet stacking unit 26 is located inside the sheet 2, such erroneous setting can be prevented. in this way,
According to this mode example, the carriage 36 and the second sheet stacking unit 26
When the sheet is not in the home position, the second sheet accommodating portion cannot be pulled out, so that the erroneous setting of the sheet can be prevented more reliably.

Next, in the fourth embodiment of the present invention, the drawer stopper 62 is axially supported by the second sheet accommodating portion 12, and is arranged at the solid line position in FIG. At this time, since the stopper 62 and the stopper abutting portion 65 on the main body side are in a position where they interfere with each other when viewed from the front of the machine, the second sheet accommodating portion 12 cannot be pulled out. When the dolly 36 and the like are in the home position, a part of the dolly 36 pushes a part of the drawer stopper 62 to rotate it.
Move to the broken line position in (a). As a result, interference with the stopper contact portion 25 is eliminated, and the stopper contact portion 25 can be pulled out. Thus, in this embodiment, the carriage 36 and the second sheet stacking unit 2
When 6 is not in the home position, the second sheet storage section 12
Since it cannot be pulled out, it is possible to more reliably prevent erroneous setting of paper. Further, in this embodiment, the cost can be reduced because the locking means 62 and 65 that are interlocked with the position of the sheet transporting means are employed without using an expensive solenoid or the like. It should be noted that the effectiveness of this form example is enhanced by combining it with the third form example. Note that the above-described respective form examples may exist independently, but may be appropriately combined.

[0018]

As described above, the first aspect of the present invention provides the first aspect.
The first sheet stacking section of the sheet storage section and the second sheet stacking section of the second sheet storage section are formed in a comb-teeth shape that meshes with each other.
When the second sheet stacking unit horizontally moves the second sheet stacking unit toward the first sheet storage unit for transfer, the upper surface of the second sheet stacking unit is located higher than the upper surface of the first sheet stacking unit, and The second sheet stacking unit transports the second sheet stacking unit when the transport unit lowers the second sheet stacking unit to transport the stacked sheets onto the first sheet stacking unit and when the sheet transporting unit returns to the second sheet storage unit. Since the sheet stacking surface of the unit is lower than the sheet stacking surface of the first sheet stacking unit, when the copy sheet is transferred from the second sheet storage unit to the first sheet storage unit by the transfer unit, the transfer unit operates as follows. It is possible to feed paper from the first sheet storage unit even without returning to the second sheet storage unit side or in the process of returning.

According to a second aspect of the present invention, the first paper accommodating portion is provided with a paper presence detecting means for detecting the presence / absence of paper and a paper near end detecting means for detecting a small amount of remaining paper, and the paper near end is provided. When the detection means detects the near end, the second sheet stacking unit is raised until the height of the sheet stacking surface of the second sheet stacking unit becomes higher than the upper surface of the sheet in the first sheet storage unit, and then the second sheet stacking unit The second sheet stacking unit is configured to be moved back and forth between the two storage units by moving the sheet storage unit to the first sheet storage unit side by the sheet transfer unit and waiting the inside of the first sheet storage unit after the movement is completed. It is possible to reduce the paper feeding loss time due to the movement time required for the unit to reciprocate between the two sheet storage units.

According to a third aspect of the present invention, a drawer switch is provided in the drawer portion that supports the second sheet storage portion, and the first switch is provided.
When the second sheet stacking section is waiting in the first sheet storage section when the sheet in the sheet storage section is near end, when the drawer switch is pressed, the sheet transfer means causes the second sheet transfer means to move to the second sheet transfer section.
Since the sheet stacking unit is moved to the second sheet storage unit, even if the second sheet stacking unit configured to move back and forth between the two storage units is inside the first sheet storage unit, the second sheet storage unit When the sheet is pulled out from the apparatus main body, the transfer means is always returned to the fixed position, so that erroneous setting of paper can be prevented.

According to a fourth aspect of the present invention, when the second sheet stacking section is inside the first sheet accommodating section or when the second sheet stacking section is moving,
Since the second sheet storage section cannot be pulled out from the apparatus body, the second sheet storage section can be pulled out from the apparatus body when the second sheet storage section is not in the fixed position in the second sheet storage section. It is possible to prevent erroneous setting.
According to a fifth aspect of the present invention, the second accommodating portion and the apparatus main body are provided with a lock means for preventing the second accommodating portion from being pulled out. Since it is released by stopping at the fixed position, the lock mechanism that locks the drawer of the paper storage unit is operated in conjunction with the transfer means without using a solenoid or the like, thereby reducing costs. Can be achieved.

[Brief description of drawings]

FIG. 1 is an overall view of an image forming apparatus including a sheet feeding device of the present invention.

FIG. 2 is an explanatory diagram of a drawn state of the sheet feeding device of the present invention.

3A and 3B are operation explanatory views of an example of the sheet feeding device of the present invention.

4 (a) and 4 (b) are explanatory views of the operation of the transfer means.

5 (a), (b), and (c) are configuration explanatory views of a stacking unit lifting mechanism.

6 (a) and 6 (b) are views for explaining the structure and operation of the locking means.

FIG. 7 is a block diagram showing the configuration of a control system of the present invention.

FIG. 8 is a flowchart showing an operation corresponding to the first exemplary embodiment of the present invention.

FIG. 9 is a flowchart showing an operation corresponding to the second example of the present invention.

FIG. 10 is a flowchart showing an operation corresponding to the third exemplary embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 image forming apparatus main body, 2 automatic document feeder, 3 reading optical system, 4 electrophotographic image forming section, 5 sheet feeder, 11, 12 sheet storage section, 13 sheet feeding means, 14
Conveyance path, 15 Registration rollers, 16 Photoconductor, 17
Transfer position, 18 fixing device, 20 paper transport means, 21
Stacking section lifting mechanism, 22 Drawer section, 25 First sheet stacking section, 26 Second sheet stacking section, 25a, 25a Sheet stacking surface, 26b Back plate, 30 Paper presence detecting means, 31 Paper near end detecting means, 36 cart, 36a Bottom plate, 36b
Standing plate, 37 carriage moving means, 40 height detection shielding plate, 41 second sheet stacking section driving means, 42 pulley, 4
3 belts, 45 upper limit detecting means, 46 lower limit detecting means, 50 carriage driving means, 51a, 51b pulleys, 5
2 belts, 54 cart position detecting shield, 55 home position detecting means, 56 moving position detecting means, 60
Drawer switch, 61 opening, 62 Drawer stopper, 63 spring, 70 Control section

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display part H04N 1/00 108 H04N 1/00 108C

Claims (5)

[Claims] 1. A first sheet accommodating section for stacking a plurality of sheets, a sheet feeding unit for feeding the sheets in the first sheet accommodating section one by one from the bottom, and a lateral direction of the first sheet accommodating section. A sheet feeding device having a second sheet accommodating portion arranged in parallel with each other, and a sheet transfer means for collectively conveying the sheets in the second sheet accommodating portion to the first sheet accommodating portion, The first sheet stacking section and the second sheet stacking section of the second sheet accommodating section are formed in a comb-like shape that meshes with each other, and the second sheet stacking section is formed by the first sheet stacking section for transfer by the sheet transporting means. When the sheet is moved horizontally to the side of the sheet storage unit, the upper surface of the second sheet stacking unit is located higher than the upper surface of the first sheet stacking unit, and the sheet transporting unit lowers the second sheet stacking unit to stack the stacked sheets. 1 When the sheet is transferred onto the sheet stacking section and when the sheet transfer means is returned to the second sheet storage section, The sheet feeding device, wherein the sheet stacking surface of the second sheet stacking unit is lower than the sheet stacking surface of the first sheet stacking unit. 2. The first paper accommodating portion is provided with a paper presence detecting means for detecting the presence / absence of paper and a paper near end detecting means for detecting a small amount of remaining paper, and the paper near end detecting means detects the near end. When it is detected, the second sheet stacking unit is raised until the height of the sheet stacking surface of the second sheet stacking unit is higher than the upper surface of the sheet in the first sheet storage unit, and then the second sheet stacking unit is used to transfer the sheet. By means of moving to the side of the first sheet storage section,
2. The paper feeding device according to claim 1, wherein the paper feeding device is put on standby in the first paper storage unit after the movement is completed. 3. A drawer switch is provided in a drawer portion that supports the second paper accommodating portion, and when the paper in the first paper accommodating portion is near end, the second paper stacking portion waits in the first paper accommodating portion. When the pull-out switch is pushed, the sheet transfer means moves the second sheet stacking unit to the second position.
3. The paper feeding device according to claim 1, wherein the paper feeding device is moved to a paper storage unit. 4. The second sheet accommodating portion cannot be pulled out from the main body of the apparatus when the second sheet accommodating portion is inside the first sheet accommodating portion or is moving. The sheet feeding device described in 1, 2, or 3. 5. The second accommodating portion and the apparatus main body are provided with lock means for preventing the second accommodating portion from being pulled out, and the lock means is such that the paper transport means is in a fixed position of the second paper accommodating portion. The sheet feeding device according to claim 1, wherein the sheet feeding device is released by stopping the sheet feeding device.