JP2000185867A - Sheet loading device, and image forming device with that device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide for a loading of sheet at large capacity while sorting it. SOLUTION: An upper stage sheet delivery tray 5 is of a movable type. A boss part 5a and a boss part 5b of the upper stage sheet delivery tray 5 are fitted into two slits 8a and 8b provided in a device main body, respectively, and a spring 7 as an energizing means is disposed in those areas other than a sheet passing width for the upper stage sheet delivery tray 5. If a sheet material exceeding a predetermined amount is loaded on the upper stage sheet delivery tray 5, the upper stage sheet delivery tray 5 is moved downward along the slits 8a and 8b by its own weight.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet stacking apparatus having a plurality of stacking sections for stacking sheets on which images are formed, and an image forming apparatus having the same.

[0002]

2. Description of the Related Art Conventionally, as this type of image forming apparatus,
There is a facsimile machine or an apparatus having a function of converting image data output from a computer into an image, in addition to a function of copying an ordinary sheet material.

[0003] In the sheet material, for example, in office equipment such as a copying machine, a printer, a printing machine, and a facsimile, and in various other equipment using sheet materials, transfer paper, photosensitive paper, thermal paper, Sheets (cut sheets) such as electrostatic recording paper, printing paper, documents, cards, and envelopes are included, and the material is not limited to paper.

Conventionally, in an electrostatographic copying machine or other image forming apparatus, for example, when each of a plurality of originals is copied onto a plurality of papers and a plurality of sets are discharged, each of the discharged papers is output. As a device that sorts according to the manuscript,
2. Description of the Related Art There is known a configuration in which a sorter is arranged in communication with a paper discharge unit of an image forming apparatus.

In this sorter, a number of trays are vertically arranged at intervals, and a plurality of sheets obtained by copying the same document are sequentially discharged to different trays to sort them.

[0006] Then, the sheets discharged to each tray are taken out individually, and it is possible to sequentially sort the sheets copied on a plurality of sheets.

However, since a plurality of trays are arranged,
There is a problem that the number of stacked sheets is limited.

Accordingly, as disclosed in, for example, Japanese Patent Publication No. 7-94302, a technique for carrying out large-capacity paper discharge has been proposed.

That is, as described in the above-mentioned publication, to increase the number of sheets of recording paper that can be stacked on the paper discharge section, it is necessary to increase the number of recording sheets from the paper placement surface of the paper discharge section to the paper discharge opening of the paper transport path. The height of the sheet may be increased and the depth of the sheet placement surface may be increased.

However, as shown in FIG. 2, when the upper sheet discharge tray 5 is removed and the depth (a) of the sheet placement surface is increased, the sheet discharged from the sheet exit portion is much lower than here. Since the sheet is discharged onto the changed sheet placement surface, the position of the sheet is likely to be disturbed, and it becomes difficult to orderly stack the sheets stacked on the sheet discharge unit.

For this reason, there is a limit to the depth of the sheet placement surface of the paper discharge unit, and it is difficult to increase the number of recording sheets that can be stacked on the paper discharge unit by using only this configuration.

Therefore, according to the technique described in Japanese Patent Publication No. Hei 7-94302, the height of the recording paper discharged from the first paper exit having a low height and stacked on the paper exit becomes a predetermined height. When the recording paper is conveyed so that the recording paper is discharged from the tall second paper exit, the number of recording papers that can be stacked on the paper discharge unit can be increased. In addition, it is possible to suppress the inconvenience that the stacked sheets are disturbed or irregular.

As described above, there has been provided an image forming apparatus capable of increasing the number of recording sheets that can be stacked on a sheet discharging unit and suppressing the inconvenience of causing disorder and irregularity in stacked sheets.

[0014]

However, in the case of the above-described prior art, the following problems have occurred.

In recent years, office space has been reduced, digitalization of images has been promoted, and even in the field of copiers, original images have been digitally read, and latent images have been written on photoreceptors using a laser or the like. , After developing with toner,
Digital copying machines capable of obtaining a high-quality copy image by transferring this onto paper have been widely used.

On the other hand, when outputting various images such as texts, graphs, and figures created by a personal computer, a word processor, and the like, a laser printer is used to obtain high-speed and high-quality output. Is coming.

Since the image forming process using this laser printer uses the same image forming process as that of the digital copying machine, it has almost the same configuration as the image forming unit and control unit of the digital copying machine except for the scanner unit. ing.

Accordingly, a digital composite image processing apparatus having both functions of a digital copying machine and a laser printer is provided for the purpose of effectively utilizing resources by sharing data, reducing the installation area of OA equipment, and the like. It has become.

Since a facsimile apparatus reads and writes an image digitally using a telephone line, a digital composite image processing apparatus having both a digital copying machine and a facsimile function is similarly provided. Further, a digital composite image processing apparatus having functions of a digital copying machine, a laser printer, and a facsimile has been provided.

As described above, when a so-called composite image forming apparatus having not only a conventional copying function but also a facsimile function and a printer function is required in the market,
In a multi-function image forming apparatus, recording of an image, particularly by receiving a facsimile, is performed at an unspecified time, and is not output by an operator. Have been.

In addition, the usage rate of the apparatus has increased, and an apparatus having a larger capacity than the conventional recording and discharging capacity has been demanded in the market.

However, in the conventional image forming apparatus, only large-capacity paper discharge is considered, and the output paper is mixed. Therefore, the user sorts ordinary recording paper and facsimile reception paper. Needed.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art. It is an object of the present invention to provide an image forming apparatus capable of stacking sheets while sorting sheets and capable of coping with a large capacity stacking. It is to provide a device.

[0024]

In order to achieve the above object, according to the present invention, there are provided a plurality of sheet stacking units which are arranged vertically above and below which sheets are stacked, and Switching means for switching which sheet stacking unit is to be stacked, wherein a sheet stackable area in at least one of the sheet stacking units above the sheet stacking unit is variably configured. And

Therefore, when sorting sheets into the respective sheet stacking sections, the amount of sheets stacked on a specific stacking section can be made variable.

It is preferable that each of the plurality of sheet stacking units has a sheet stacking plate, and at least one of the sheet stacking plates is movable in the sheet stacking direction.

An urging means for urging the sheet stacking plate in the direction in which the sheets are stacked is provided, and as the sheets are stacked on the sheet stacking plate, the urging means is urged by its own weight. The sheet stacking plate may be moved against the urging force to widen the sheet stackable area.

Detecting means for detecting whether or not the sheet discharging path to any one of the sheet stacking sections is obstructed by the movement of the sheet stacking plate is provided, and the obstruction is detected by the detecting means. In such a case, it is preferable that no sheet is loaded on the sheet loading section.

When it is detected by the detection means that the sheet is obstructed, sheets may be stacked on another sheet stacking section.

When it is detected by the detecting means that the image is obstructed, image information to be output can be stored in the image storing means without forming an image on the sheet.

Also, a plurality of sheet stacking units arranged vertically above and below which the sheets on which images are formed by the image forming means are stacked, and which sheet stacking unit among the plurality of sheet stacking units is stacked. An image forming apparatus comprising: a switching unit configured to switch a sheet stackable area of at least one of the sheet stacking units above the sheet stacking unit.

It is preferable to be able to select to which sheet stacking section the image-formed sheet is to be discharged or to store image information to be output without performing image formation in the image storage means.

A plurality of image forming modes may be provided, and the sheet stacking section may be changed according to the image forming mode. The image forming mode includes at least one of a facsimile mode for forming an image sent from a telephone line, a copy mode for forming an image read from a document image, and a printer mode for forming an image sent from an external device. It is good to include one.

[0034]

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the dimensions of the components described in this embodiment,
The materials, shapes, relative arrangements, and the like are not intended to limit the scope of the present invention only to them unless otherwise specified.

An image forming apparatus according to an embodiment of the present invention will be described with reference to FIGS.

First, an outline of the entire facsimile apparatus as an image forming apparatus according to an embodiment of the present invention will be described with reference to FIGS.

FIG. 3 is a schematic sectional view of an image forming apparatus (facsimile apparatus) according to an embodiment of the present invention.
FIG. 4 is a perspective view of the image forming apparatus (facsimile apparatus) according to the embodiment of the present invention.

3 and 4, reference numeral 101 denotes an apparatus main body; 102, an original mounting table configured to stack a plurality of originals S; 103, an image reading unit for reading image information of the original S; Is a recording device main body composed of a laser beam printer, 105 is an operation unit including a display unit and input keys, etc., 106 is a document transport unit, 107 is a document pressing unit, 108 is a contact image sensor, and 109 is a document discharge tray. It is.

Reference numeral 110 denotes a laser scanner;
Denotes an image forming unit; 112, a cassette sheet feeding unit; 113, a lower sheet discharging unit configured to stack a plurality of sheet materials P on an upper cover of the apparatus main body 101;
Reference numeral 8 denotes an upper sheet discharging unit disposed further above the lower sheet discharging unit, 114 denotes a cartridge cover, and 115 denotes A
It is a DF (auto document feeder) cover.

Reference numeral 116 denotes an outer document guide, 117 denotes a document holding plate, 118 denotes an inner document guide, 119 denotes a partition between the laser scanner 110 and the recording apparatus main body 104, and 120
Is a control unit of the facsimile machine, 121 is a sheet conveying unit,
Reference numeral 122 denotes a front cover, reference numeral 123 denotes a paper discharge cover, reference numeral 124 denotes a resist transport unit, reference numeral 125 denotes an MP (multi-paper) paper feed unit which can also serve as a front cover, and reference numeral 150 denotes a double-sided transport unit.

The image reading section 103 separates the originals S stacked on the original placing table 102 one by one by a separation roller 106b pressed against the separation pad 106a, and the transfer roller pressed against the transfer roller 106c pressed by a pressing spring. 106d
Thus, a U-turn paper path constituted by a part of the outer document guide 116 and a part of the inner document guide 118 is conveyed.

Further, the original is conveyed to the close contact type image sensor 108 by the paper feed roller 106f or the like pressed against the paper feed roller 106e pressed by the pressing spring, and the original is pressed by the original pressing portion 107 by the elastic force of the original pressing plate 117 deformed. After reading the image information of the original S while pressing the S against the contact image sensor 108, the original S is pressed by a discharge roller 106h pressed against a discharge roller 106g pressed by a pressing spring. To be discharged.

During this time, the original S is guided by the outer original guide 116 and the inner original guide 118.

The document table 102 is provided with a slider 102a slidable in a direction perpendicular to the direction of transport of the document S (the width direction of the document S), and the document stacked on the document table 102 by the slider 102a. Both sides of S can be aligned.

When the original S is a long original, the extension original tray 102b is opened to prevent the rear end of the original S from protruding from the original table 102 and hanging down.

The contact type image sensor 108 irradiates light from the LED array as a light source to the image information surface of the original S,
The image information is read by forming an image of the reflected light reflected from the image information surface on a sensor element by a SELFOC lens (trademark).

The cassette paper feeding unit 112 is provided in the apparatus main body 101.
It is arranged at the bottom of the.

The sheet material P stacked on the sheet feeding cassette 112a is pressed upward by the middle plate spring 112f by the middle plate spring 112f, and is pressed against the semicircular sheet feeding roller 112b, whereby the separation pad 112c is pressed. While being separated one by one (friction piece separation method).

The leading end of the separated sheet material P is detected by the registration sensor 124b after a predetermined time.

If the registration sensor 124b does not detect the leading end of the sheet material P within a predetermined time after the start of sheet feeding, it is determined that a jam has occurred, and a display is made on the operation unit 105.

If the registration sensor 124b detects the leading end of the sheet material P within a predetermined time after the start of sheet feeding, the separated sheet material P is supplied to the sheet feeding roller 112b.
, And is guided by the pressure nip N of the registration roller pair 124a.

The registration roller pair 124a is controlled to stop rotating when the leading end of the sheet material P reaches the pressure nip N of the registration roller pair 124a.
The leading end of the sheet material P abuts against the press-contact nip portion N of the registration roller pair 124a in the rotation stopped state and is received. Thereafter, the sheet material is fed by the sheet feeding roller 112b, so that the sheet material P is somewhat bent. A loop is formed, and the skew of the sheet material P is corrected by parallelizing the tip side of the sheet material P along the nip line of the press-contact nip N by the reaction force of the bending loop.

Next, the registration roller pair 124a is driven at a predetermined control timing, the sheet material P is conveyed, and the registration roller pair 124a and the registration sensor 1
The sheet transport U-turn guide 124d, which is composed of a resist transport guide 124c in which the reference numeral 24b is disposed, and a part of a main body frame forming a skeleton of the apparatus main body 101, the apparatus main body 1
01 is inverted by the MP guide 125g arranged at the position No. 01.

Further, the sheet material P being fed continues to be conveyed even after reaching the pre-transfer roller pair 124e, and the TOP sensor 12
4f, the tip position is detected, and the photosensitive drum 111a is detected.
After the sheet feeding and image output timings are adjusted so that the leading edge of the toner image formed on the sheet P and the leading edge of the sheet material P coincide, the sheet is conveyed between the transfer charger 111f and the photosensitive drum 111a.

The side edge of the sheet material P is regulated by a sheet regulating plate 112d movably mounted in accordance with the sheet size so that skewing and non-feeding do not occur.

The image is recorded on the lower surface side of the sheet material P stacked on the sheet cassette 112a.

The presence or absence of the sheet material P is detected by the cassette sensor 112h.

The cassette 112a has a capacity of about 250 sheets, and is configured to be pulled out toward the front of the apparatus main body 101 (front loading method).

The sheet sizes that can be stacked are A3, A
4, A5, B4, B5, letter, and legal.

The facsimile apparatus is used in the main body 10 of the apparatus.
The MP (multi-paper) sheet feeding unit 125 can be arranged by removing the front cover 122 arranged on the front surface of the unit 1.

The MP (multi-paper) paper supply unit 125 has an openable and closable MP tray 125f.
By pulling out the MP extension tray 125e, recording paper of a size that cannot be stacked on 5f prevents the trailing end of the recording paper from protruding and hanging down.

The MP middle plate 125c is a MP middle plate spring 125h.
However, since the MP middle plate 125c is pushed down by a cam (not shown) in the standby state, the sheet material P can be stacked on the MP middle plate 125c.

From the control unit 120 of the facsimile apparatus, the MP
When a signal for starting sheet feeding is transmitted, a cam (not shown) is rotated, and the stacked sheet material P is pressed against the semicircular MP sheet feeding roller 125a by releasing the pressing of the MP middle plate 125c. Then, the sheets are conveyed while being separated one by one (friction piece separation method) by the MP separation pad 125b.

The separated sheet material P continues to be pressed and conveyed by the MP feed roller 125a and the MP separation pad 125b, and is transferred to the pre-transfer roller pair 124e.

Within a predetermined time from the start of sheet feeding, TO
If the P sensor 124f does not detect the leading end of the sheet material P, it is determined that a jam has occurred, and a display is made on the operation unit 105.

Further, the sheet material P being fed continues to be conveyed even after reaching the pre-transfer roller pair 124e, and the leading end position is detected by the TOP sensor 124f.
After the sheet feeding and image output timings are adjusted so that the leading end of the toner image formed on 1a and the leading end of the sheet material P coincide, the sheet is conveyed between the transfer charger 111f and the photosensitive drum 111a.

Since the MP sheet feeder 125 does not have a registration mechanism, the sheet material P has its side end face regulated by a sheet regulating plate 125i movably mounted in accordance with the sheet size so that skew or non-feeding does not occur. ing.

The image is recorded on the upper surface side of the sheet material P stacked on the MP tray 125f.

The presence or absence of the sheet material P is determined by the MP sensor 12.
5d.

The number of sheets that can be stacked in the MP sheet feeding section 125 is about 1
It is 00 sheets, and it is possible to add a postcard or a business card to a sheet size that can be fed by attaching the MP sheet feeding unit 125.

The cassette sheet feeding section 112 and a second-stage cassette sheet feeding section having the same configuration as that of the cassette sheet feeding section 112 (not shown) can be separated and combined as options. The number of stackable sheets can be changed from about 250 sheets to about 600 sheets.

The main body of the recording apparatus 104 is provided with a laser scanner 110 based on an image signal output from the control section 120.
A modulation signal is emitted from a laser beam oscillator 110a, and the modulated beam is irradiated by a polygon mirror 110b onto a photosensitive drum 111a of an image forming unit 111 to form image information on the surface of the photosensitive drum 111a. The image information is transferred to the sheet material P fed from the sheet feeding unit 112 to the image forming unit 111.

The photosensitive drum 111a is connected to the primary charger 111.
b, developing roller 111c and cleaning blade 111
d and is integrally incorporated in the recording cartridge 111e, and is configured to be detachable from the apparatus main body 101.

The surface of the photosensitive drum 111a is 1
Charged uniformly by the next charger 111b,
The scanning light from the polygon mirror 110b is turned back to the mirror 1
When reflected and irradiated at 10c, a latent image is formed, and the latent image is visualized by toner supplied from the developing roller 111c.

The photosensitive drum 111a of the image forming unit 111
A transfer charger 111f is disposed in a peripheral portion, and a thermal fixing device 111g is disposed in a sheet conveyance path downstream of the photosensitive drum 111a.

After the toner image formed on the surface of the photosensitive drum 111a is transferred by the transfer charger 111f, the sheet material P is conveyed along the recording sheet conveying section 121.

The sheet material P conveyed along the recording sheet conveying unit 121 is fixed with a toner image by a heat fixing unit 111g, and a switching operation is performed by a fixing flapper 126 according to a signal from the control unit 120. Is selected, the sheet material P is conveyed.

When the sheet material P is not conveyed to the double-sided conveying section 150, the switching sheet flapper 127 disposed further downstream causes the upper sheet discharging section 128 or the lower sheet The rear sheet discharge tray 1 disposed at the rear of the apparatus main body 101 by the paper discharge unit 113 or the rear discharge roller 129.
30 is selectively discharged.

As described above, the sheet material P discharged to the upper sheet discharging section 128 or the lower sheet discharging section 113 is stacked with the image information on the lower side, and the rear sheet discharging tray 1
The sheet material P discharged to the sheet 30 is configured to be stacked with the image information facing upward.

The main unit 101 has a cartridge cover 1
14, the recording cartridge 111e is pulled out of the apparatus main body 101 and can be replaced by opening the cartridge cover 114.

The cartridge cover 114 is provided with an interlock mechanism.
14 is open, or if the recording cartridge 111e is not set in the apparatus main body 101, the recording apparatus main body 1
04 does not work.

Further, the drum exposure prevention shutter 111i provided on the recording cartridge 111e is adapted to be linked with the setting of the recording cartridge 111e in the apparatus main body 101, and the cartridge cover 114 is opened to move the recording cartridge 111e to the apparatus main body 101. Is set, the shutter 111i opens, and the recording cartridge 111e is opened.
When the shutter 111 is taken out of the apparatus main body 101,
By closing i, unnecessary exposure of the photosensitive drum 111a is prevented.

If a jam occurs during recording, the cartridge cover 114 and the front cover 12
2. By opening any one of the paper discharge covers 123, the sheet material P staying inside can be taken out.

The partition section 119 is a duct for separating the laser scanner 110 and the recording apparatus main body 104, and the air generated by the air flow by a fan (not shown) is generated by the laser scanner 1 by the heat generated from the recording apparatus main body 104.
10 prevents the water vapor evaporated from the sheet material P from being condensed and dripping on the sheet material P.

The double-sided conveying section 150 is disposed at the rear of the apparatus main body 101, and converts the sheet material P conveyed from the thermal fixing device 111 g based on an image signal output from the control section 120.
By switching the fixing flapper 126, the two-sided conveyance unit 1
The sheet material P can be conveyed to 50.

By switching the fixing flapper 126, the sheet material P conveyed to the two-sided conveying unit 150 is heated by the heat fixing device 111g by the curling roller pair 152 and heated and pressed by the heat fixing device 111g. The curl is corrected, and the sheet is conveyed to the switchback roller 153 which is the next conveying means.

The sheet material P conveyed to the switchback roller 153 is once conveyed onto a cover 112g disposed above the paper feed cassette 112a, and stored in the lower part of the apparatus main body 101.

Thereafter, when the rear end of the sheet material P is conveyed to the vicinity of the switchback roller 153, the rear end of the sheet material P is detected by a sensor (not shown), and before the sheet material P exits the switchback roller 153. The transport stops once.

Then, the switchback roller 153 rotates in the reverse direction, and the sheet material P is conveyed to the re-feeding unit 154 disposed on the lower rear side of the duplex conveying unit 150.

The skew of the sheet P conveyed to the re-feed unit 154 is corrected by a plurality of rollers arranged in the re-feed unit 154, and then reaches the re-feed roller 155. The sheet passes through the inside of the sheet cassette 112a and is transported to the apparatus main body 101 again.

FIG. 5 is a block diagram of a control system 300 of a facsimile apparatus using a laser beam printer (hereinafter, referred to as LBP) according to an embodiment of the present invention.

In the figure, reference numeral 301 denotes a CPU for controlling the entire facsimile apparatus.
A ROM 312 for storing a control program for the image processing, a RAM 313 used as a work area for various data processing and a temporary storage unit for image information, an image processing unit 314 for scaling the image, converting the resolution, and the like.

The CPU 301 is provided with a calendar, a clock function, and the like having a known configuration. An area for storing important system setting information, such as one-touch key destination information and software switch information, in the RAM 313 is provided by a battery backup for power failure or the like. Protected from accidental disability.

The control system of the facsimile apparatus is the CPU described above.
The configuration is such that 301 and the following elements 302 to 310 are connected through an interface.

The operation unit 302 includes various key switches such as a numeric keypad 315, a function key 316, a one-touch key 317, a start key 318a, and a stop key 318b.

The display unit 303 includes an LCD 319 for displaying various messages and various LEDs for displaying a transmission mode and the like.
320a, a tally lamp 320b for notifying a distant operator of a communication state and occurrence of a failure, and the like.

The reading unit 304 includes a driving unit 3 such as a reading motor.
21, a reading sensor 322 for reading an image, an image processing unit 323 for shading and binarizing the read image,
It is composed of various sensors 324 and the like for detecting a document.

The recording unit 305 is a driving unit 32 such as a recording motor.
5, a recording unit 326 for controlling a laser scanner and an electrophotographic process, an image processing unit 327 for smoothing an image to be recorded, and various sensors 328 for detecting recording paper and the like.

The communication control unit 306 which performs outgoing calls, incoming calls, encoding of image data and the like has a connection unit 329 composed of MODEM, NCU, etc., and a communication network 307 and a handset 308 are connected to the connection unit 329.

The CPU external interface 309 is a CPU
An interface for directly transmitting and receiving data from the external device 301. The interface is used as a scanner printer of an external computer by connecting to an external computer via a line such as RS232C, SCSI, or LAN. The HDD 310 is used as a large-capacity nonvolatile memory for storing image information and the like.

FIG. 6 is a conceptual diagram showing the basic operation of the LBP.
This will be described with reference to FIG.

In FIG. 6, reference numeral 400 denotes a semiconductor laser which blinks a laser beam for image data to be recorded;
Is a polygon motor, 402 is a polygon mirror rotated by the polygon motor 401, 403 is an optical system for performing image formation and tilt correction, 404 is a photodetector, 405 is a return mirror, 406 is a photosensitive drum, 407 is a developing device,
408 is a recording paper, 409 is a conveyance guide, and 410 is a fixing device.

In the above configuration, first, the laser beam emitted from the semiconductor laser 400 is
The light is deflected by being reflected by the light beam 2 and is irradiated onto the photosensitive drum 406 via the optical system 403 and the return mirror 405 (main scanning).

At this time, the head is located by the photo detector 404 and the irradiation position is determined.

While the main scanning is completed for one line, the photosensitive drum 406 rotates by one line (sub-scan).

The image formed on the photosensitive drum 406 as described above is developed by the developing device 407 and the recording paper P
(408).

Further, the sheet is transported along the transport guide 409,
The image is fixed by the fixing device 410 and discharged.

Incidentally, the above-mentioned photosensitive drum 406 and developing unit 40
7. The components of the sub-scanning system such as the fixing device 410 are synchronously driven by a recording motor (not shown), a gear, a belt, and the like.

Next, the sheet discharge section will be described in detail with reference to FIGS.

FIG. 1 is a schematic cross-sectional view of a main part of an image forming apparatus according to an embodiment of the present invention, and shows a cross-sectional view of a sheet discharging section. FIG. 2 shows an embodiment of the present invention. FIG. 2 is a comparative configuration diagram for explaining a main part of the image forming apparatus, and shows a state in which there is no upper sheet discharge tray in FIG.

In the figure, reference numeral 1 denotes a sheet material (image formed image) on which the toner image is fixed by the above-mentioned heat fixing device 111g, and a switching operation is performed by the fixing flapper 126 according to a signal from the control unit 120, and conveyed. Sheet) P,
Upper sheet discharge unit 1 arranged at the upper part of the apparatus main body 101
A discharge flapper as a switching unit for selectively switching discharge to the lower sheet discharge unit 113 or the lower sheet discharge unit 113.

The upper sheet discharging section 128 and the lower sheet discharging section 113 constitute a sheet stacking section.

Reference numeral 2 denotes a lower discharge unit disposed to lower the curl of the sheet material P conveyed to the lower sheet discharge unit 113 by the discharge flapper 1 and to stack the sheet material on the lower sheet discharge tray 4 as a sheet stacking plate. It is a paper roller, and is set slightly faster than the transport speed of the thermal fixing device 111g for curl correction.

The lower sheet discharge tray 4 is provided in the main body 10 of the apparatus.
1 and is capable of discharging and stacking about 200 sheets.

The upper sheet discharging section 128 is also provided with the upper sheet discharging roller 3 similarly to the lower sheet discharging roller 2 disposed in the lower sheet discharging section 113, and the conveying speed and the roller diameter are different. They are configured to be identical.

The sheet material P discharged by the upper discharge roller 3 is transferred to the upper sheet discharge tray 5 serving as a sheet stacking plate.
To be loaded.

The upper sheet discharge tray 5 is a movable tray, and the bosses 5a and 5b of the upper sheet discharge tray 5 enter into two slits 8a and 8b provided in the apparatus main body 101, respectively. Upper sheet ejection tray 5
A spring 7 as an urging means is disposed in an area other than the sheet passing width of the sheet feeding sheet, and when a sheet material larger than a predetermined value is loaded on the upper sheet discharging tray 5, the sheet material is moved along the slits 8a and 8b by its own weight. The upper sheet discharge tray 5 can be moved downward.

Further, a projection 5c is provided on the side surface of the upper sheet discharge tray 5, and the sensor 6 serving as detecting means disposed in a region other than the sheet passing width similarly to the spring 7 allows the upper sheet discharge tray 5 to be moved. Position can be detected.

Since the sheet material P to be stacked has various types of paper, the spring force of the spring 7 is 64 basis weight of the sheet material P.
It is configured such that about 100 sheets can be stacked based on the range of up to 90 g / m ² .

Further, the user can designate the paper discharge port from the operation unit 105. For example, in the case of FAX reception, the paper is discharged to the lower sheet discharge tray 4 and the output paper when the printer function is used is displayed in the upper line. It is possible to specify discharge to the sheet discharge tray 4, discharge of all output paper from the upper sheet discharge unit 128, and the like.

As described above, when a so-called composite type image forming apparatus having not only a conventional copying function but also a facsimile function and a printer function is required in the market, the usage rate of the apparatus increases, and More than the recording output capacity has been required in the market.

Therefore, in the present embodiment, as described above, the lower sheet discharging section 113 and the upper sheet discharging section 128 located at a position higher than the lower sheet discharging section 113 are provided. It has sheet discharge trays 4 and 5 on which recorded recording paper is stacked, and has an upper sheet discharge section 128.
The upper sheet discharge tray 5 is urged upward by a spring 7, and the upper sheet discharge tray 5 is moved downward by its own weight when recording paper is loaded.

As a result, the output paper can be sorted for each job such as FAX reception paper when the FAX function is used and printer recording paper when the printer function is used, so that the user does not need to perform the sorting work.

Further, if a user who does not discharge paper for each of a plurality of jobs wants to discharge a large amount of paper, the operation unit 10
5 to the upper sheet discharge tray 5, even if a large amount of output is output to the upper sheet discharge tray 5, if a predetermined number or more of sheet materials are stacked, the upper sheet Since the sheet discharge tray 5 is moved downward by its own weight of the sheet material,
There is no problem such as jamming due to excessive loading of sheet materials. As described above, even when a large amount of sheets are discharged, the upper sheet discharge tray 5 gradually moves downward due to the weight of the sheet material, so that the dimension a shown in FIG. 2 does not become extremely large. Therefore, it is possible to supply an image forming apparatus that does not cause disorder or irregularity in the stacked sheet materials. In other words, even if the paper output trays are positioned one above the other, the space of the lower tray can be used when storing them in the upper tray, so that the height can be increased without increasing the height.
Large-capacity sheets can be stored with good consistency.

Further, when a large amount of paper is discharged to the upper sheet discharge section 128, the upper sheet discharge tray 5 moves downward and lowers to a position where the discharge port of the lower sheet discharge section 113 is closed. If the user specifies to switch the paper discharge unit for each sheet, the lower sheet discharge unit 1
The output paper from 13 hits the upper sheet discharge tray 5 to cause a jam.

Therefore, the projections 5c provided on the side surfaces of the upper sheet discharge tray 5 allow the upper sheet discharge tray 5 to move.
The upper sheet discharge tray 5
Moves downward to a position that closes the discharge opening of the lower sheet discharge unit 113, even if the user has specified to switch the discharge unit for each job, the following is performed.

That is, the image is not discharged from the lower sheet discharge section 113, and the RAM 313 or H
The image information is stored in the DD 310 and displayed on the display unit 303 of the operation unit 105 so as to remove the recording paper stacked on the upper sheet discharge tray 5, and the user removes the output paper.
After the upper sheet discharge tray 5 is raised to a position where the discharge port of the lower sheet discharge unit 113 is not blocked, the sheet is discharged to the lower sheet discharge tray 4.

Alternatively, especially for a user who may mix output papers, if the upper sheet discharge tray 5 is lowered to a position to close the discharge opening of the lower sheet discharge unit 113, all output papers may be used. Can be set to be discharged from the upper sheet discharge unit 128.

By doing so, the expensive RAM 313,
Alternatively, since the HDD 310 is not required, an inexpensive device can be provided to the user.

In the above description, the sheet stacking portion for discharging the sheet after image formation is provided at two places (two stages).
Although the configuration in the case of providing is shown, the present invention is not limited to such a configuration, and a plurality of (three or more) sheet stacking units may be provided.
Some of them may be configured such that the stackable area is variable.

In this way, the sheets can be sorted into a plurality of locations, and some of the specific portions can be used for large-capacity loading, and the range of use can be further expanded.

[0132]

As described above, according to the present invention, a plurality of sheet stacking sections are provided, and at least one of the sheet stacking sections is configured to have a variable sheet stacking area. The variable loading section can handle large-capacity loading.

As the sheets are stacked on the sheet stacking plate, the sheet stacking plate is moved by the weight of the sheet against the urging force of the urging means so as to expand the sheet stackable area. The sheets can be stacked in an orderly manner without disturbing the stacking of sheets as in the case where the stackable area is enlarged.

A detecting means is provided to detect whether or not the sheet discharging path to any of the sheet stacking sections is obstructed by the movement of the sheet stacking plate. If a sheet is not stacked on the sheet stacking section, a jam can be prevented.

In this case, by stacking sheets on another sheet stacking portion, it is possible to cope with jam prevention with a simple configuration.

In this case, the image information to be output can be stored in the image storage means without forming the image on the sheet.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a main part of an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a comparative configuration diagram for explaining a main part of the image forming apparatus according to the embodiment of the present invention.

FIG. 3 is a schematic configuration sectional view of an image forming apparatus (facsimile apparatus) according to the embodiment of the present invention.

FIG. 4 is a perspective view of an image forming apparatus (facsimile apparatus) according to the embodiment of the present invention.

FIG. 5 is a block diagram of a control system of the image forming apparatus using the laser beam printer according to the embodiment of the present invention.

FIG. 6 is a conceptual diagram of a basic operation of the laser beam printer.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 discharge flapper 2 lower discharge roller 3 upper discharge roller 4 lower sheet discharge tray 5 upper sheet discharge tray 6 sensor 7 spring 101 device main body 102 document mounting table 103 image reading unit 104 recording device main unit 105 operation unit 106 original Conveyance unit 107 Document pressing unit 108 Contact image sensor 109 Document ejection tray 110 Laser scanner 111 Image forming unit 112 Cassette feeding unit 113 Lower sheet ejection unit 114 Cartridge cover 115 ADF (auto document feeder) cover 116 External document guide 117 Document holding plate 118 Inner document guide 119 Partitioning section 120 Control section 121 Sheet transport section 122 Front cover 123 Discharge cover 124 Registration transport section 125 MP (multi-paper) paper feed section 126 Fixing flapper 127 Switching flapper 128 Upper sheet discharge section 150 Double-sided conveyance section 154 Re-feed section

Claims (10)

[Claims] A plurality of sheet stacking units for vertically stacking sheets, and switching means for switching which one of the plurality of sheet stacking units is to be stacked. In the sheet stacking apparatus, a sheet stackable area in at least one of the sheet stacking units above the sheet stacking unit is variably configured. 2. The sheet according to claim 1, wherein each of the plurality of sheet stacking units has a sheet stacking plate, and at least one of the sheet stacking plates is configured to be movable in a sheet stacking direction. Loading device. 3. An urging means for urging the sheet stacking plate in a direction in which the sheets are stacked, wherein the urging means is urged by its own weight as the sheets are stacked on the sheet stacking plate. 3. The sheet stacking apparatus according to claim 2, wherein the sheet stacking plate is moved against the urging force of the means to expand a sheet stackable area. 4. A detecting means for detecting whether or not a sheet discharging path to any one of the sheet stacking sections is obstructed by the movement of the sheet stacking plate, and the detecting means may obstruct the sheet discharging path. The sheet stacking apparatus according to claim 2, wherein when the detection is detected, no sheet is stacked on the sheet stacking unit. 5. The sheet stacking apparatus according to claim 4, wherein when it is detected that the sheet is obstructed by the detection means, the sheet is stacked on another sheet stacking unit. 6. An image storage device according to claim 1, wherein when the detection unit detects that the image is obstructed, the image information to be output is stored in the image storage unit without forming an image on the sheet. An image forming apparatus comprising the sheet stacking device according to 4. 7. A plurality of sheet stacking units, which are arranged vertically above and below, on which sheets on which images are formed by the image forming means are stacked, and which of the plurality of sheet stacking units is to be stacked. An image forming apparatus comprising: a switching unit that switches a sheet stackable area in at least one of the sheet stacking units above the sheet stacking unit. 8. The image forming apparatus according to claim 1, wherein the sheet on which the image is formed is discharged to the sheet stacking section, or the image information to be output without forming the image is stored in the image storing means. The image forming apparatus according to claim 7, wherein 9. The image forming apparatus according to claim 7, further comprising a plurality of image forming modes, wherein a sheet stacking unit is changed according to the image forming modes. 10. The image forming mode includes a facsimile mode for forming an image sent from a telephone line, a copying mode for forming an image read from a document image, and a printer mode for forming an image sent from an external device. The image forming apparatus according to claim 9, comprising at least one of the following.