JP2003226448A - Image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the paper bending of a tabbed transfer material or the turnoff at the end of a tab portion thereof, possibly caused when its tabbed side is at the head, and allow stable carriage of the tabbed transfer material. <P>SOLUTION: The image forming device is so configured that the transfer material is made to abut on a temporarily stopped resist roller and then the resist roller is rotated for feeding the transfer material toward a transfer region to allow transfer means to transfer a toner image formed on an image carrier to the transfer material. It comprises control means for prohibiting the temporary stop of the resist roller. <P>COPYRIGHT: (C)2003,JPO

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 an electrophotographic copying machine, a printer, or a facsimile, and more particularly to an image forming apparatus suitable for using a transfer material with a tab.

[0002]

2. Description of the Related Art In a conventional image forming apparatus such as a copying machine or a printer, when a transfer material with a tab is conveyed, if the transfer material having a tabbed side on the leading side is conveyed, the transfer roller is temporarily stopped by a registration roller. There is a tendency that the tab portion comes into contact with the registration roller, causing defects such as paper bending and tab end tip bending. Therefore, when loading a transfer material with a tab, the transfer tray is loaded so that the side with the tab is on the rear end side (hereinafter, when the side with the tab is on the front side, the tab portion is on the downstream side). The tab part is also called the upstream side when the side with the tab is the rear end side).

However, at the time of double-sided image formation, even if the tab portion is conveyed on the one side so that the tab portion is on the upstream side, the tab portion is on the downstream side after passing through the reversing device, so that the paper is bent or the tip of the tab portion is bent. The problem of will occur.

Even so, when performing double-sided image formation on the transfer material with tabs, the operator manually manually turns over the transfer material with tabs imaged on one side, and then re-tabs. The paper is loaded in the paper feed tray so that the unit is on the upstream side, and the image is formed on the back side.

[0005]

SUMMARY OF THE INVENTION In the present invention, when a transfer material with a tab (hereinafter also referred to as a tab sheet) is used, even if the tab portion is located on the downstream side, the above-mentioned problems due to the registration rollers occur. It is an object of the present invention to provide an image forming apparatus capable of passing a sheet without performing the above.

[0006]

Means for Solving the Problems After a transfer material is brought into contact with a temporarily stopped registration roller, the registration roller is rotated to send the transfer material toward a transfer area,
An image forming apparatus configured to transfer a toner image formed on an image bearing member to the transfer material by a transfer means, wherein an image forming apparatus is provided with a control means for prohibiting the temporary stop of the registration roller. .

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION An example of an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic diagram showing the structure of an image forming apparatus according to the present invention. A copying machine as an image forming apparatus according to the present embodiment has an automatic document feeder 1 at the top of the copying machine body.
In addition, the main body of the copying machine includes an image reading device 2, an image forming unit 3, a transfer material storage unit 4, a paper feeding unit 5, a reverse sheet discharging / refeeding unit 6, and an ADU 8 serving as a reverse conveying unit. ing.

The automatic document feeder 1 is a device that feeds the originals one by one, conveys the originals to an image reading position, and discharges the originals after the image reading to a predetermined place.

The automatic document feeder 1 includes a document placing table 11 on which a document is placed, a document separating means 12 for separating a document placed on the document placing table 11, and a document separated by the document separating means 12. A document conveying unit 13 including a plurality of rollers for conveying, a document ejecting unit 14 for ejecting the document conveyed by the document conveying unit 13, and a document ejection table on which the document ejected by the document ejecting unit 14 is placed 15 and a document reversing unit 16 including a pair of rollers for reversing the front and back of the document when reading images on both sides of the document.

In terms of the processing process, a plurality of originals (not shown) placed on the original placing table 11 are
The original separating means 12 separates the sheets one by one, and the original conveying means 13 conveys the originals toward the original reading position.

The original reading position is set to the original conveying means 1
It is provided in the lower part of the sheet 3, and the image of the original is read there through the slit 21.

The document from which the image has been read is discharged onto the document discharge tray 15 by the document discharge means 14.

On the other hand, when reading images on both sides of a document, the document whose image on one side has been read is guided to the document reversing means 16, and when the trailing edge of the document is bitten by the roller, the roller is moved. By rotating the document in the reverse direction so that the front and back sides of the document are reversed, and the document is conveyed again by the document conveying means 13, the image on the other surface (second surface) can be read at the document reading position.

Such steps are repeated for the number of originals placed on the original placing table 11. Further, the automatic document feeder 1 is constructed in a foldable manner, and the original is directly placed on the platen glass 22 by raising the automatic document feeder 1 to open the platen glass 22. It is constructed so that it can be copied.

The image reading device 2 is a means for reading an image of a document to obtain image data, and includes a lamp 231 for illuminating the document through the slit 21 and a first mirror for reflecting light reflected from the document. A first mirror unit 23 formed by integrating 232, a second mirror 241 and a third mirror 242 that reflect light from the first mirror 232.
And a second mirror unit 24, which is integrated with the image forming lens 25, which forms an image of reflected light from the second mirror unit 24 on an image pickup device (hereinafter referred to as CCD) 26 described later, and an image forming lens. It has a line-shaped CCD 26 that photoelectrically converts the optical image formed by 25 to obtain image information.

The image information is subjected to appropriate image processing and then temporarily stored in a memory (not shown).

In the mode in which the image reading device 2 reads the document fed by the automatic document feeding device 1, the first mirror unit 23 and the second mirror unit 2 are used.
4 is fixed at the position as shown.

In a mode of reading an image of a document directly placed on the platen glass 22, the first mirror unit 23 and the second mirror unit 24 are
It is performed by moving along the platen glass while maintaining the optical path length.

The image forming section 3 is an area for finally forming an image on the transfer material based on the image data obtained by the image reading device 2.

In the embodiment, image formation is carried out by using an electrophotographic process, and an image carrier having a photoconductive photosensitive layer on its surface (hereinafter referred to as a photosensitive drum).
31, a charger 32 for uniformly charging the surface of the photoconductor drum 31, an operation based on image data after image processing,
A laser writing system 33, which is an exposing unit for exposing the photosensitive drum 31 to form a latent image, and a developing device for reversing and developing the latent image formed on the photosensitive drum 31 into a toner image. 34, a transfer pole 35 for transferring the toner image onto a transfer material, and the transfer material on which the toner image is transferred on the photosensitive drum 3.
1 has a static eliminator 36 for promoting separation by performing AC corona discharge from above to eliminate static electricity, and a cleaning unit 37 for cleaning the photosensitive drum 31 after the transfer process is completed.

After being separated by the static eliminator 36, a conveying belt 39 for conveying the transfer material toward the heating roller type fixing device 38, a fixing discharging roller 61, a discharging roller 63, and other conveying means are provided. It is provided on the same horizontal line as the electric appliance 36.

In the image formation according to the above-mentioned structure, the electrostatic latent image is formed by dot exposure by the laser writing system 33 after the photosensitive drum 31 rotating in the direction of the arrow is sequentially charged by the charger 32 by an appropriate driving means. The electrostatic latent image is formed by the developing device 34 and converted into a toner image by the developing device 34, and then the transfer material is fed by the start of rotation of the registration roller 57 which has been temporarily stopped. It is achieved by transferring it. That is, even after the leading end of the transfer material is abutted against the registration roller 57 which is temporarily stopped, the conveyance roller 56 is further rotated, so that the transfer material is bent at the upstream loop forming portion W to remove the paper curl. is doing.
After that, the transfer material is fed by the registration roller 57 whose rotation is controlled in synchronization with the toner image on the photosensitive drum 31, and the toner image is transferred onto the transfer material by the action of the transfer pole 35. ing.

The transfer material after transfer is separated from the photosensitive drum 31 by the action of the static eliminator 36, and the fixing device 3
After being subjected to the heating / pressurizing action of 8, it is discharged to the outside of the machine.

On the other hand, the photosensitive drum 3 which has passed the transfer area
1 continues to rotate further, the residual toner is removed by the cleaning means 37, and preparation for the next image formation is made.

The process for forming an image on a normal transfer material has been described above. The present invention is characterized in that, when a tab sheet is conveyed, the control means for prohibiting the temporary stop of the registration roller in the case where the tabbed side is the first side can prevent the sheet bending and the tab portion tip bending. To do.

FIG. 2 is a partially enlarged view of the transfer material conveying path to the image forming portion in FIG. In the figure, A1 is a writing position from the laser writing system, A2 is a transfer position where a transfer pole is arranged, and 561 is a sensor for synchronous adjustment with a toner image on a photosensitive drum, at least one of which is a conveyance unit. It is arranged on a line orthogonal to the direction. B1 is a sensor position for detecting the leading end of the transfer material sent by the transport roller 56, and A is the photosensitive drum 31 from the writing position A1 to the transfer position A2.
The above-mentioned arc length (hereinafter, referred to as arc length), B indicates the conveyance length from the sensor position B1 to the transfer position A2.

The sensor 561 is arranged at the writing position A1.
When the arc length from the transfer position A2 to the transfer position A2 is A, the transport length from the sensor position B1 to the transfer position A2 is B, and the tab protrusion length is C, the position is set to satisfy the condition of A <BC. There is a need to.

Next, the tab sheet conveyance and the writing to the photosensitive drum by the control means for prohibiting the temporary stop of the registration rollers will be described under the above-mentioned sensor arrangement conditions.

FIG. 3 is a diagram for explaining the timing of writing on the portion corresponding to the tab portion on the photosensitive drum.

In the figure, is a sensor,
, Shows an example of detecting the leading edge of the tab sheet with two (plural) sensors. In the figure, C indicates the tab protrusion length, and D indicates the distance that the tab sheet runs during the time from the sensor position B1 to the start of writing.

As will be described later, the tab protrusion length C is input by an operator in advance and is a control unit F which is a control means.
(See FIG. 1) The timing with the toner image is calculated.

The control means in the present embodiment is a control section containing a program for operating a machine, which feeds and conveys the transfer material, charges the photosensitive drum, writes, develops, transfers and feeds the material. It has a function of calculating the timing of transportation, etc., and an operation command, selection, storage, and other functions.

When the front end of the tab portion passes the sensor 561, the front end of the tab portion is detected by the sensor 561 and the signal is sent to the control unit F (see FIG. 1) to transfer the transfer material at a predetermined distance. At the time when the sheet is conveyed by D, writing corresponding to the tab portion is started on the photosensitive drum, and the writing image is synchronized. After that, the transfer material is moved to the transfer position A2 at a distance (B
-D) is conveyed (this corresponds to the distance A from the writing position A1 to the transfer position A2 in FIG. 2), and the transfer position A2
And the transfer to the tab portion becomes possible.

In the case where the tip other than the tab portion passes through the sensor, similarly to the time after the tip is detected, after the traveling distance (D-C), the photosensitive drum corresponds to the tab portion. Writing is started and synchronized with the written image. After that, the transfer material is a distance (BD) from the transfer position A2.
Then, the transfer to the tab portion becomes possible.

In the case where the leading edge is detected by two (plural) sensors, the tab sheet of the other side is advanced at the tab protrusion length C after the leading edge of the tab portion is detected by one sensor. The sensor detects the end portion other than the tab portion. in this case,
Writing is started on the photosensitive drum corresponding to the tab portion after the D-C conveyance from the later signal. After that, the transfer material is conveyed a distance (BD) to the transfer position A2 and can be transferred to the tab portion.

The above is also a case where the tip is detected by two (a plurality of) sensors and none of the sensors detects the tip of the tab portion. In this case, writing to the photosensitive drum corresponding to the tab portion is started after the D-C conveyance from the detection signal.

As can be seen from the above description, if A>
In the case of B-C, the tab end of the tab sheet detected by the sensor 561 may pass the transfer position A2 and may not be synchronized.

The tab sheet of which the leading edge is detected further advances, and is nipped by the registration roller 57 whose temporary stop is prohibited and conveyed to the transfer area.

On the other hand, in the case of the tab sheet having the tab portion on the upstream side, the transport rollers 55 and 56 are used similarly to the tabless transfer material.
Registration roller 57 sent by
The tip (side without tabs) contacts the sheet, makes a bend in the loop forming portion W, corrects paper curl, and is timed with the toner image on the photosensitive drum.

In the case of double-sided image formation on tab paper,
Since the tab portion is located on the downstream side on one of the surfaces, the control for prohibiting the temporary stop of the registration roller 57 is automatically selected during the transportation on the surface located on the downstream side. That is, it is possible to avoid the sheet bending and the tab tip breakage by the control for prohibiting the temporary stop of the registration roller 57 only when the tab section is on the downstream side.

Next, the usage conditions for using the tab sheet will be described. FIG. 4 is a view showing a stacked state of the transfer material with tabs loaded in the paper feed tray.

FIG. 4A shows a tab sheet (5 sheets) divided into 5 parts.
It shows a state in which the tabs are stacked, and the tab sheets of the first set are (1) to (5), and the second set is (6) to (1).
0), the tab portions are stacked so that the phases thereof are shifted one by one.

That is, in the present embodiment, when tab sheets are used, the same number of tab sheets as the number of divisions (sections) for dividing the image-formed transfer material are (1) in FIG.
(2) It is a precondition that a plurality of sets of tab sheets, which are stacked in the arrangement as described above, are loaded into a tab sheet-only feed tray.

Here, the number of divisions refers to the number of tabbed sheets inserted between specific pages of the image-formed tabless transfer material for division. For example, when dividing into 5 parts, as shown in FIG.
When dividing into 10 pieces, 10 pieces of tab sheets each consisting of 10 sheets are used (however, when dividing into 10 pieces, one set of 5 division tab sheets can be used).

First, the operator confirms in advance how many pieces the image-formed tabless transfer material is to be divided into,
A plurality of sets of tab sheets having a number of tabs equal to the number of divisions (insertions) are loaded in the paper feed tray.

The operator selects the tab sheet mode (inter-sheet mode) and inputs the tab sheet insertion position (page) for dividing the print through a ten-key described later to enable tab sheet feeding. .

Here, the tab sheet mode is a mode for inserting the tab sheet into the tabless transfer material on which an image is being formed and dividing the tab sheet, and which sheet is inserted in advance between which sheet. Is input with the ten-key pad, it is calculated by the control unit F (see FIG. 1), and when the insertion point comes, it is automatically switched to the tab paper loading tray and tab paper is supplied as an intersheet. It is a mode in which the tab is controlled to be inserted into the insertion position after the image is formed on the tab or the like.

For example, in the case of two sets of tab sheets loaded as shown in FIG. 4A, the tab sheet (1) is first fed, and then the image formation is performed from another sheet feed tray. An image is formed on the previous tabless transfer material (hereinafter, also referred to as a sheet), then the tab sheet (2) is fed, an image such as an index is formed, and then, again on the sheet. Image formation. Similarly, the tab sheet is inserted from the tab sheet (3) to (5) or the tab sheet (6) to (10) through a similar repeating process, and the tab sheet as shown in FIG. The two sets of inserted image-formed transfer materials are completed.

Tab paper (1) to (5), (6) to (1
While proceeding to 0), the number of fed tab sheets is counted and stored in the control section F (see FIG. 1). In addition, the number of the tab portion that passes through the sensor is determined by inputting the number of tabs (division number) of the tab paper to be loaded, and the tabs in the direction orthogonal to the transport direction (hereinafter, also referred to as Y direction) The control unit F calculates the timing at which the parts are indexed.

FIG. 4 (c) is a tab sheet divided into five parts, and a set of five tabs is located at the same position. In FIG. 4 (d), the tab parts are stacked so that their phases are not aligned. Shows tabbed paper. If tab sheets with these arrangements are loaded into the paper feed tray with the tab sides at the beginning, and the paper is fed, a control is applied to prohibit pausing by inputting the tab protrusion length and the number of tab divisions. Although the breakage of the tab tip is avoided, the tab position in the Y direction is not in the above-mentioned precondition, so that writing to the tab portion may be impossible.

Further, in the present embodiment, the distance between the tabbed transfer material and the paper is adjusted so that the paper adjacent to the front and back of the tabbed transfer material having the tab portion on the downstream side does not come into contact with the tab paper. The paper feed timing is controlled so as to be wider than the space between the paper sheets. This is because the tab sheet is not paused with respect to the preceding and succeeding sheets in the pause prohibition mode, so that the timing is shifted. That is, the space between the tab paper and the paper before and after the tab paper is made larger than the space between the papers, and the mutual contact is avoided. The space between the papers here means the space between the leading edge of the tab and the paper or the space between the non-tab side and the paper.

Next, the paper feeding process from the transfer material storage unit (or ADU) will be described. Returning to FIG. 1, in the transfer material storage unit 4, storage containers 405, 415, 425 for storing the transfer materials in a stacked state and paper feeding units 406, 4 are provided.
Paper feed tray 400 in which 16, 426 are integrally configured,
410 and 420 are arranged in the vertical direction, and the paper feeding units 406, 416, and 426 include the paper feeding rollers 407 and
417 and 427 and separation rollers 408 and 41 for preventing stacking
8 and 428.

Transfer materials of different types are stored in the paper feed trays. In the present embodiment, in the case where the A4 size normal transfer material (without tab) is stored in the paper feed tray 400 and the A4 size tab paper having a tab portion on the long side is stored, which transfer material is used? Also has a form in which the short side extends along the transport direction.

Each paper feed tray has a side edge regulating plate and a rear edge regulating plate for regulating the side edge and the trailing edge of the transfer material which can be fixed.

The structure of the regulation plate (not shown) can use a known technique, and the position of the regulation plate is detected by the size detecting means S1 including an appropriate sensor, and the information is controlled by a computer (CPU). It is adapted to be taken into the means F.

The paper feeding section 5 serves as a transportation means for transporting the transfer material from each of the paper feeding trays to the image forming section 3, and a pair of transportation rollers (hereinafter, also simply referred to as transportation rollers) R1, R2, It has R3, R4, R5, and R6.

The conveying roller pairs R1 to R3 serve as pre-registration rollers and are the paper feeding units 406 and 41.
6 and 426 are preferably provided integrally, and in the present embodiment, they are integrally configured. It should be noted that the pre-registration roller R2 that feeds the tab sheet is controlled so as not to temporarily stop when feeding the tab sheet having the tab portion on the downstream side, like the registration roller 57.

PS is a photo sensor, and for example, determines whether the transfer material fed from the paper feed tray 400 by the paper feed roller 407 has reached the conveyance roller pair R1 provided downstream of the separation roller 408. It has a function of detecting and is arranged at a position immediately in front of the conveying roller pair R1.

Reference numeral 55 denotes a conveying roller provided downstream of the conveying roller R4, which is provided at a confluence portion where a sheet sent out through the ADU 8 and a transfer material fed from the sheet feeding tray 400 are joined. is there.

The reverse discharge / re-feed unit 6 is a region for reverse discharge of the transfer material after transfer / fixing and for re-feed of the transfer material according to the double-sided image forming mode, and the fixing discharge roller 61. When the transfer material discharged by the method is discharged to the outside of the machine as it is, when it is discharged after being turned upside down, the transfer material is directed toward the registration roller 57 to form an image on the back surface (second surface) of the transfer material. A switching unit 62 is provided for switching the transport path between the case of re-feeding the sheet by re-feeding.

The image-formed transfer material as it is, that is,
When ejecting with the image surface facing upward, the switching means 62 is positioned at the position indicated by the alternate long and short dash line in the figure, and when ejecting the image-formed transfer material by inverting it, the switching means 62 In the position indicated by the solid line, the sheet conveyed by the fixing discharge roller 61 is fed into the conveyance path provided with the conveyance rollers 600, 610, 620, and the rear end reaches the position before the conveyance roller 600. The operation of the roller group is stopped at the timing when the conveyance roller 600 is rotated in the opposite direction to the above direction, so that the left side of the switching means 62 is passed and the discharge tray 64 outside the machine is passed. To discharge.

Further, in the mode in which the image is continuously formed on the second surface of the transfer material, the switching means 62 is positioned at the position shown by the solid line in the figure, and the transfer material conveyed by the fixing discharge roller 61 is discharged. The same process as the above-mentioned image formation is carried out by feeding the sheet to the ADU 8 through each conveying roller of the reverse sheet discharging / refeeding section 6 driven by a motor, reversing the transfer material, and then sending it out to the registration roller 57. Then, the sheet is discharged to the sheet discharge tray 64.

As described above, the ADU 8 reverses the transfer material from the front side to the backside and circulates the transfer material in the circulation path (registration roller 57-fixing device 38-reversal discharge / refeed section 6-A).
It is a reversing conveyance means that forms a part of the circulation path from the DU 8 to the registration roller 57, and includes a plurality of roller pairs (hereinafter, also simply referred to as conveyance rollers) 800, 810, 820, 83.
0, 840, 850.

Among the transport rollers, the roller denoted by reference numeral 800 is a roller which is driven and controlled in the forward and reverse directions by a motor (not shown).
It is called an ADU reversing roller.

The behavior of the transfer material scheduled to be image-formed on the second side, especially in the ADU, is as follows.
Of the roller group (600, 610, 620) is moved along the conveyance path, and then the ADU reversing roller 800 continues to move in the same direction by the driving action of the ADU reversing roller 800.
The movement is stopped with the rotation stop operation of the ADU reversing roller while being sandwiched by the U reversing roller, and thereafter,
The driving force of the ADU reversing roller 800 which is rotated in the opposite direction to the rotation direction is received to switch back, enter the right side conveyance path at the branch point, and by the driving action of the conveyance rollers 810 to 850 in a reversed state. After moving to the right on the horizontal conveying path and moving upward, it reaches the registration roller 57 via the conveying rollers 55 and 56.

Next, the procedure of the operation for inserting the tab sheet into the image-formed transfer material will be described with reference to the drawings.

FIG. 5 is a view showing a part of the operation panel. In FIG. 5, 100 is an operation panel provided on the upper surface of the machine (see 200 in FIG. 1). (A) is a tab sheet mode selection unit, (B) is a display composed of a liquid crystal display panel, (C) is a numeric keypad, (D) is a copy button for starting image formation, and (E) is a determination unit.

FIG. 6 is a flow chart for explaining an operation procedure when inserting the tabbed transfer material into the image formed transfer material.

The flow of the operation procedure of FIG. 6 will be described below with reference to the reference numerals of FIG. In FIG. 6, a range surrounded by a one-dot chain line is a block manually selected and instructed by an operator, and a range surrounded by a solid line shows a block in which the machine automatically operates.

First, when the tab sheet button of the tab sheet mode selection section (a) is pressed in step S1, the tab sheet can be supplied, and in step S2, the tab sheet insertion position is set through the ten keys (c). Input and specify the position. In step S3, when the tab division number and the tab protrusion length of the tab paper loaded in the paper feed tray are input, a message as to whether or not double-sided image formation is performed is displayed on the display (b) in step S4, and N (NO) In the case of), if the NO button of the determination unit (e) is pressed, it is displayed in step S5 whether or not the tab portion is on the downstream side. Here, in the case of N, when the NO button of the determination section (e) is pressed, the setting is completed, the copy button (d) of step S6 is pressed, the registration rollers of step S7 are temporarily stopped, Proceed to the pause mode in which the toner image on the photosensitive drum is timed.

In the case of Y (YES) in step S5, if the YES button of the determination section (e) is pressed, the setting is completed, the copy button (e) in step S8 is pressed, and the temporary stop prohibition in step S9 is performed. Go to mode.

If Y (double-sided image type) in step S4,
When the YES button of the determination section (e) is pressed, a message indicating whether the tab is on the downstream side is displayed on the display (b) in step S10. If N in step S10,
The setting is completed when the NO button of the determination section (e) is pressed, the copy button (d) is pressed in step S11, and the tab section is on the upstream side in the image formation on the front surface (first surface) in step S12. Therefore, the process proceeds to the temporary stop mode in which the toner image is temporarily stopped and the timing is adjusted to the toner image. In the case of printing on the back surface (second surface), the temporary stop prohibition mode is entered.

In the case of Y in step S10, if the YES button of the judgment section (e) is pressed, the setting is completed, and the copy button (d) is pressed in step S13,
In the image formation on the front surface (first surface) in 14, the tab portion is located on the downstream side, and therefore the temporary stop prohibition mode is set, and the back surface (second surface) is set.
(Surface) image formation proceeds to the pause mode.

As described above, when the operator selects the position of the tab portion and inputs the tab division number, the tab protrusion length and the like, when the position of the tab portion is on the downstream side, the toner on the photosensitive drum is For the synchronous adjustment of the image and the paper, a control means (mode) for prohibiting the temporary stop of the registration roller by a signal of a sensor that detects the front end of the paper is applied, and problems such as paper bending and tab edge breakage can be avoided.

[0076]

EFFECTS OF THE INVENTION In the transfer material with tab, it is possible to prevent paper bending and breakage of the tip of the tab portion, which tend to occur when the side with tab is on the leading side, and it is possible to stably convey the transfer material with tab.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a configuration of an image forming apparatus according to the present invention.

FIG. 2 is a partially enlarged view of a transfer material conveyance path to an image forming unit in FIG.

FIG. 3 is a diagram for explaining a timing of writing on a portion corresponding to a tab portion on the photosensitive drum.

FIG. 4 is a diagram showing a stacking state of transfer materials with tabs to be loaded in a paper feed tray.

FIG. 5 is a diagram showing a part of an operation panel.

FIG. 6 is a flowchart for explaining an operation procedure when inserting a transfer material with a tab into a transfer material on which an image has been formed.

[Explanation of symbols]

1 Automatic document feeder 2 Image reader 3 Image forming section 4 Transfer material storage 5 paper feeder 6 Reverse output / refeed section 8 ADU (circulation transportation means) 31 Image carrier (photosensitive drum) 55,56 Conveyor rollers 57 Registration roller 561 sensor

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03G 21/14 G03G 21/00 372 F term (reference) 2H027 DC00 DC04 ED06 ED16 EE01 FA05 FA35 ZA07 2H072 AB07 HA03 HB07 3F048 AA02 AA04 AA05 AB01 BA11 BA21 BA27 BB02 BB05 CA09 CC03 DA07 DB02 DB06 DB11 DC12 EA15 EB33 EB36 3F102 AA02 AA11 AB01 BA02 BA07 BB02 CA03 CB02 DA08 EA03 FA08 3F343 FA02 FA18 FB02 FC15 FC30 GA01 GB01 GC01 GD01 JA01 MA03 MA09 MA15 MA26 MB03 MB13 MC06 MC08

Claims (8)

[Claims] 1. A transfer material is brought into contact with a temporarily stopped registration roller, and then the registration roller is rotated to send out the transfer material toward a transfer area to form a toner image formed on an image carrier. An image forming apparatus configured to transfer to the transfer material by a transfer means, wherein an image forming apparatus is provided with a control means for prohibiting the temporary stop of the registration roller. 2. The image according to claim 1, wherein the control means for prohibiting the temporary stop is applied when the tabbed side of the tabbed transfer material is conveyed first. Forming equipment. 3. The image forming apparatus according to claim 1, wherein it is possible to select whether or not the tabbed side is on the leading side and whether or not the print mode is double-sided image formation. 4. An arc length from the writing position to the transfer position on the surface of the image carrier is A, a transport length from a sensor position for detecting the beginning of the transfer material to the transfer position is B, and a tab protrusion length is C. 3. The image forming apparatus according to claim 2, wherein a sensor for detecting the leading end of the transfer material is arranged at a position where the condition of A, B <B-C is satisfied. 5. The image forming apparatus according to claim 4, wherein information on the number of tab divisions and the tab protrusion length of the transfer material with tabs can be input. 6. When the sensor detects the tip of the tab portion, the image writing corresponding to the tab portion is imaged after a predetermined time delayed by the tab protrusion length from when detecting the tip other than the tab portion. The image forming apparatus according to claim 5, wherein the image forming apparatus starts on a carrier. 7. A plurality of the sensors are arranged on a line orthogonal to the conveying direction, and image writing corresponding to the tab portion is started on the image carrier based on the information of the sensor detected late. The image forming apparatus according to claim 5. 8. When transporting a tabless transfer material which is adjacent to the front and rear of a tabbed transfer material having a tabbed side as a head, the space between the tabbed transfer material and the tabless transfer material is set between the tabless transfer materials. 8. The image forming apparatus according to claim 1, wherein the paper feed timing is controlled so as to be wider than the paper interval.