JPH1069137A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To use a post-processing equipment, without reducing an advantage of a nearly vertical path system, in a nearly vertical path system image forming device. SOLUTION: In the device main body 4 of an image forming device 2, a paper feeding part 8 and a paper ejecting part 12 are provided in the lower and upper parts of an image forming means part 6, respectively and a nearly vertical sheet path P is formed. The post-processing equipment 20 is fitted to the side surface of the device main body 4 and the post-processing equipment 20 and the paper ejecting part 12 are provided along the top surface of the device main body 4 and connected by a sheet material carrying unit 22 having an independent sheet path and a carrying function.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine, a printer, a facsimile and the like by an electrophotographic system, and more particularly, to form a target image on a sheet by feeding and conveying the sheet substantially vertically. The present invention relates to a substantially vertical pass type image forming apparatus.

[0002]

2. Description of the Related Art In recent years, image forming apparatuses having a composite function such as a copying machine, a printer, and a facsimile have become widespread. Until now, such an image forming apparatus has been based on a copying machine, and when used as a printer, a reversing mechanism is mounted on a peripheral machine or the like in order to output in page order.
However, with the rapid spread of personal computers in recent years, printer-based construction is becoming mainstream.
This adopts a substantially vertical path method, that is, a method in which a sheet feeding unit is arranged below the image forming unit and a sheet discharging unit is arranged above, and the image is discharged with the image surface facing downward. Compared to conventional copiers, the transport path is very short, and most of the transport path can be opened just by opening the side of the machine, so the output time from paper supply to paper discharge is short, sheet transportability and Very good jam removal.

[0003]

However, there is a problem that it is difficult to mount post-processing devices such as a sorter, a stapler, and a finisher. Specifically, since the upper portion of the image forming apparatus serves as a sheet material discharge port, if a post-processing device is directly installed there, the height of the entire apparatus increases, and accordingly, a scanner as a document table and The operation unit becomes high, and the operability deteriorates. Also, the height of the apparatus is naturally limited in relation to the operability, and it is practically impossible to arrange many trays. Further, since the image forming apparatus receives the weight of the post-processing device, it is required to improve the mechanical strength of the image forming apparatus, which inevitably increases the cost. As described above, when the post-processing device is used, there is a problem that the advantage of the substantially vertical path method cannot be fully utilized.

Accordingly, an object of the present invention is to provide an image forming apparatus that can use a post-processing device while fully utilizing the advantages of the substantially vertical path method.

[0005]

SUMMARY OF THE INVENTION According to the present invention, a post-processing device is installed at a position where height and weight problems do not occur with respect to an image forming apparatus. It is based on the idea of contacting. More specifically, according to the first aspect of the present invention, a sheet feeding unit is provided below the image forming unit and a sheet discharging unit is provided above the image forming unit. In a substantially vertical path type image forming apparatus that forms a target image on a material surface, a sheet material transport unit that communicates a post-processing device mounted on the image forming apparatus and the paper discharge unit on an upper surface of the image forming apparatus. Is provided along the upper surface of the apparatus, and the sheet material transport unit includes a stack unit for stacking image-formed sheet materials discharged from the paper discharge unit, and the sheet material discharged from the sheet discharging unit. A stack conveying means for conveying the sheet material to the stack portion, a post-processing conveying means for conveying the sheet material to the post-processing device, and an entry of the sheet material into the post-processing conveying means and the stack conveying means. Branching means for switching, And a control means for controlling the splitting means, and employs a configuration that.

According to a second aspect of the present invention, in the configuration of the first aspect, when the sheet material is caused to enter the post-processing transport means, the branching means is turned on, and the sheet material is transported to the stack transport means. When entering the vehicle, control to turn off the branching means is performed.
According to a third aspect of the present invention, in the configuration of the first aspect, there is provided a sheet full detecting means for detecting whether or not the sheet material stacked on the stack portion is full. The sheet material is made to enter the post-processing transport means. According to a fourth aspect of the present invention, in the configuration of the first or second or third aspect, the trigger signal for operating the branching unit is transmitted from a sheet material detection sensor provided at the most downstream side of the conveyance path of the image forming apparatus. Signal.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. As schematically shown in FIG. 1, an image forming unit 6 is provided in the apparatus main body 4 of the image forming apparatus 2, and a sheet feeding unit 8 is provided below the image forming unit 6. A paper discharge unit 12 is provided above. Further above the apparatus main body 4, via the scanner tables 14 and 16,
A scanner 18 for reading a document is installed, and a post-processing device 20 such as a sorter, a stapler, a finisher, etc. having a stack portion 20a is mounted on a side surface of the apparatus main body 4. A sheet conveying unit 22 having an original conveying path and a conveying function is provided on the upper surface of the apparatus main body 4 along the upper surface.

The paper supply unit 8 includes a plurality of paper supply cassettes 24, 2
6 are accommodated therein, for example, each containing sheet materials 28 and 30 having different sizes. The above-described vertical arrangement of the image forming unit 6 with the image forming unit 6 inside extends the sheet path extending substantially vertically, that is, from the sheet feeding unit 8 to the sheet discharging unit 12 through the image forming unit 6. P
Are formed.

The image forming means 6 mainly includes a photosensitive member 32 as an image carrier which is driven to rotate counterclockwise,
An optical writing device 34 for forming an electrostatic latent image on the photoconductor 32 is provided. More specifically, the photoconductor 3
2, a charger 36 for uniformly charging the photoconductor 32 is provided.
And an eraser (not shown) for erasing charges in the non-image area
A developing device 38 for visualizing the electrostatic latent image, a transfer device 40 for transferring the visible image formed by the developing device 38 to a sheet material and transporting the sheet material, and a photoconductor after the transfer 3
A cleaning unit 42 for removing the toner remaining on the photosensitive member 32 and cleaning the photosensitive member 32;
2 is provided with a static eliminator (not shown) for erasing the electric charge remaining in the device 2. Further, a fixing device 44 for fusing and fixing the toner image transferred by the transfer device 40 is provided between the transfer device 40 and the paper discharge unit 12. The optical writing device 34 is a unit that converts image data from the scanner 18 into an optical signal and performs optical writing corresponding to a document image and optical writing according to image information from a personal computer. Is scanned through a polygon mirror, and scanning light is guided to the photoreceptor 32 by an fθ lens via a reflecting mirror to form an electrostatic latent image.

The sheet material 28 or 30 is
, And are separated one by one by a separation roller pair 48, and are conveyed by a conveyance roller 50 in a substantially vertical sheet path. Before the transfer device 40, the sheet material 28 or 3
A pair of registration rollers 52 for sending 0 between the transfer device 40 and the photoconductor 32 at a predetermined timing are arranged.
A sheet material detection sensor 54 is provided in front of the registration roller pair 52.

The paper discharge section 12 is provided with a paper discharge roller 56. In front of the paper discharge roller 56, a paper discharge sensor 58 as a sheet material detection sensor located at the most downstream of a substantially vertical sheet path. Is provided. The scanner 18 has a contact glass 60 on which a document is placed, a white pressure plate 61 for pressing the document, an illumination lamp 62 for irradiating light on the document placed on the contact glass 60, and a light reflected from the surface of the document. A scanning mirror 63 that reflects light, and a pair of optical path turning mirrors 64 that move at half the speed of the scanning mirror 63
a, 64b, an imaging lens 66, and a CCD 67.

The main process equipment of the image forming unit 6, the paper feed unit 8, and the paper discharge unit 12 are built in the apparatus main body 4.
By opening the side plate 4a of the apparatus main body 4, most of the substantially vertical sheet path is opened. This facilitates jam clearance.

The sheet conveying unit 22 includes a sheet discharging unit 12.
Stacking section 68 for stacking image-formed sheet materials ejected from the sheet feeding section,
Transport means 70 for transporting the sheet material from the stack, and transport means 7 for post-processing which transports the sheet material to the post-processing device 20
2, a branching unit 74 for switching the path of the sheet material exiting from the sheet discharging unit 12, and a control unit 76 for controlling the branching unit 74.
(FIG. 2). In the stack part 68,
A sheet full detection sensor 78 is provided as sheet full detection means for detecting that the sheet material is full. The stack conveying means 70 includes a sheet path 75 communicating between the sheet discharge unit 12 and the stack unit 68, and a discharge roller positioned downstream of the sheet path 75 and discharging the sheet material to the stack unit 68. 77 are provided. The post-processing conveyance means 72 includes a sheet path 79 that communicates between the paper discharge unit 12 and the post-processing device 20, and conveyance rollers 80 and 81.
A discharge roller 82 that is located downstream of the sheet path 79 and discharges the sheet material to the post-processing device 20;
0 and 81, and a sheet material detection sensor 83 located between them. A sheet full detection sensor 83 as a sheet full detection unit is also provided in the stack unit 20a of the post-processing device 20.
Is provided. The branching means 74 includes a branching claw 74a,
Solenoid 74b that drives this branch claw 74a (FIG. 2)
It is composed of

As shown in FIG. 2, detection signals from a sheet discharge sensor 58, a sheet fullness detection sensor 78, a sheet fullness detection sensor 83, and the like are input to a control means 76 as a microcomputer. On / off control of the solenoid 74b of the branching means 74 is performed based on the information. When the processing by the post-processing device 20 is performed, the setting is performed through the operation panel 84.

Next, the image forming operation and the operation of the sheet material conveying unit 22 will be described. The optical writing device 34 performs optical writing according to information on the surface of the photoreceptor 32 whose surface is uniformly charged by the charger 36, the image of the original read by the scanner 18, or the image from the personal computer.
An electrostatic latent image is formed. The electrostatic latent image on the photoreceptor 32 has a non-image portion erased by an eraser, and then a toner charged by the developing device 38 is attached to form a visible image. On the other hand, for example, the sheet cassette 2
From 4, the sheet material 28 is fed by a feed roller 46, separated by a separation roller 48 one by one, and fed into a sheet path. The registration roller pair 52 sends the sheet material 28 to the transfer device 40 at a timing when the visible image on the photoconductor 32 and the sheet material 28 coincide with each other at the nip portion between the photoconductor 32 and the transfer belt. The sheet material 28 onto which the toner image has been transferred is sent to the fixing device 44, where the toner image is transferred to the sheet material 28.
Is heated and fixed. The sheet material on which the image has been formed is delivered to the paper output unit 1
2, when a mode is selected in which processing is not required in the post-processing device 20, as shown in FIG.
The solenoid 74b is turned on by the control means 76, and the branch pawl 74a rotates downward. As a result, only the sheet path 75 of the stack transport unit 70 is opened, and the sheet material 28 or 30 is transported by the stack transport unit 70 and stacked on the stack unit 68. This is a so-called normal sheet discharging operation. When a mode to be processed by the post-processing device 20, for example, a staple mode, is selected, as shown in FIG.
With the solenoid 74b kept off, only the sheet path 79 of the post-processing conveyance means 72 is opened. The sheet material 28 or 30 discharged from the paper discharge unit 12 is conveyed by the post-processing conveyance unit 72 and sent to the post-processing device 20. Although not shown, the sheet material 28 or 30 is stacked on the stack unit 20a after a predetermined job such as staples is completed in the post-processing device 20.

Although the normal paper can be discharged to the stack section 20a of the post-processing device 20, the normal paper is discharged to the sheet material transport unit unless post-processing is required to shorten the so-called first copy time. 22 to the stack section 68. The reason why the opening of the post-processing transporting means 72 corresponds to the off position of the solenoid 74b is that the post-processing device 20 has a larger number of stacks, so that the continuous paper passing time may be longer. This is to reduce the size and cost of the solenoid 74b by reducing the duty of the solenoid 74b. Although not shown, the post-processing device 20 has a stapling function inside.

Next, the relationship between the stack function and the sheet full detection sensor 78 will be described. In a case where a mode that does not require processing in the post-processing device 20 is selected, and a job that exceeds the number of stacks in the stack unit 68 of the sheet material transport unit 22 is executed, as illustrated in FIG.
Based on a detection signal from the sheet full detection sensor 78, the control means 76 turns off the solenoid 74b and switches the conveyance path to the post-processing conveyance means 72. Therefore, image formation can be continuously performed at once by the total number of sheets of the sheet material transport unit 22 and the number of sheets of the post-processing device 20. Based on the information of the sheet full detection sensor 83, when the stack unit 20a of the post-processing device 20 is full, the above-described switching may not be performed. FIG. 6 is a flowchart of the above operation. As can be seen, the solenoid 74b is turned on based on the detection signal of the sheet discharge sensor 58 located at the most downstream position of the sheet path of the apparatus main body 4. The sheet full detection sensor 78 has a configuration in which, for example, a swingably provided arm is moved by a sheet material discharging operation, and the return position is detected to determine whether the sheet is full. This is described in, for example,
Since this is a well-known technique disclosed in Japanese Patent Publication No. 280774, details thereof will be omitted.

As described above, the post-processing device 20 is connected to the apparatus main body 4.
So that the height is not bulky, and
The post-processing equipment 2
0 and the paper discharge unit 12 of the apparatus main body 4 are connected by a sheet material transport unit 22 provided along the upper surface of the apparatus main body 4, so that post-processing can be performed without reducing the advantages of the substantially vertical path method. The use of the device 20 can be enabled.

[0019]

According to the first aspect of the present invention, the sheet conveying unit is provided along the upper surface of the apparatus to connect the paper discharging unit and the post-processing device 20, and the sheet conveying unit is usually provided with the sheet conveying unit. Since the paper discharge and the conveyance to the post-processing device are switched according to the mode of the image forming apparatus, the post-processing device can be used without diminishing the advantages of the substantially vertical path method. When the post-processing is not necessary, the sheet is discharged to the stack section of the sheet material transport unit, so that the time of the first copy can be shortened. According to the second and fourth aspects of the present invention, since the transport path to the post-processing device is opened by turning off the branching unit, the drive source of the branching unit can be miniaturized in addition to the effect of the first aspect. ,
Cost reduction can be achieved.

According to the third aspect of the present invention, the sheet-full detecting means is provided, and when the stacking capacity of the sheet conveying unit is exceeded, the apparatus is automatically switched to the post-processing apparatus and is stacked. In addition to the effects described in item 1,
Image formation of a number exceeding the stack capacity of the sheet conveying unit can be performed continuously without stopping the apparatus.

[Brief description of the drawings]

FIG. 1 is a schematic side view of an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a control block diagram.

FIG. 3 is a main part side view showing a state in which the sheet is conveyed to a stack unit of the sheet material conveying unit.

FIG. 4 is a main part side view showing a state of being transported to a post-processing device.

FIG. 5 is a main part side view showing a state in which the stacking unit of the sheet material transport unit is stacked on a post-processing device when the stacking unit is full.

FIG. 6 is a flowchart illustrating an operation of the sheet material transport unit.

[Explanation of symbols]

Reference Signs List 6 Image forming unit 8 Paper feed unit 12 Paper discharge unit 20 Post-processing equipment 22 Sheet material transport unit 28, 30 Sheet material 58 Paper discharge sensor as sheet material detection sensor 68 Stack unit 70 Stack transport unit 72 Post-process transport Means 74 Branching means 76 Control means 78 Sheet fullness detection sensor as sheet fullness detection means

Claims (4)

[Claims] A sheet feeder provided below the image forming means and a paper ejector provided above the image forming means, for feeding and conveying the sheet material substantially vertically to form a target image on the surface of the sheet material; In an image forming apparatus of a substantially vertical path type, a sheet material transport unit for communicating a post-processing device mounted on the image forming apparatus with the paper discharge unit is provided along an upper surface of the image forming apparatus. The sheet material transport unit includes a stack unit for stacking image-formed sheet materials discharged from the paper discharge unit, and a stack transport for transporting the discharged sheet material to the stack unit. Means, a post-processing conveyance means for conveying the sheet material to the post-processing device, a branching means for switching the entry of the sheet material into the post-processing conveyance means and the stacking conveyance means, and the branching means Control to control And an image forming apparatus. 2. A control is performed to turn on the branching means when the sheet material enters the post-processing conveyance means, and to turn off the branching means when the sheet material enters the stacking conveyance means. The image forming apparatus according to claim 1, wherein: 3. A sheet full detecting means for detecting whether or not the sheet material stacked on the stack portion is full, and when it is determined that the sheet material is full, the sheet material is sent to the post-processing conveying means. The image forming apparatus according to claim 1, wherein the image forming apparatus is caused to enter. 4. The image forming apparatus according to claim 1, wherein the trigger signal for operating the branching unit is a signal from a sheet material detection sensor provided at the most downstream side of the conveyance path of the image forming apparatus. The image forming apparatus as described in the above.