JPH11311883A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device equipped with a punching device capable of drilling a hole without adjusting positions of a recording sheet and the punching device piercing the sheet. SOLUTION: This device is allowed to stop the sheet P being fed by paper feeder rollers 105 by register rollers 906 to perform stagger correction and timing adjustment, and to form the image by a photoreceptor drum 912. In the meantime, a punching device 109 piercing the sheet P is provided on the downstream side vicinity of the register rollers 906, and in the case when piercing of the punching hole is selected, after punching by the punching device 109, the image is formed by the photoreceptor drum 912. In such a manner, a transporting route between the stagger correcting position of the sheet P and the punching device 109 is shortened, the need of the positional correction between the punching device 109 and the sheet P is eliminated, and hence the device is miniaturized.

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, and more particularly, to an image forming apparatus having, for example, a sheet processing means for punching a sheet to be image-formed by an image forming means.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus and a sheet processing apparatus connected thereto, an image forming operation on a recording sheet (hereinafter referred to as a sheet) and a punching operation on a sheet are as follows. Was done in that order.

(1) The sheet feeding means pulls in the sheet from the sheet feeding port, and subsequently sends the sheet to the resist conveying means.

(2) Sheet detecting means in front of the resist conveying means detects the presence of a sheet.

(3) The resist conveying means temporarily stops the sheet sent from the paper feeding means in order to align the leading edge of the sheet and to take a timing between the image formed by the toner on the photosensitive member and the sheet.

(4) When all the preparations necessary for continuing the image forming operation are completed within a specified time, the resist conveying means sends the sheet between the photosensitive drum as the image forming means and the transfer means.

(5) A toner image is transferred between the photosensitive drum and the transfer means on the sheet sent out by the resist transfer means.

(6) The sheet on which the toner image has been transferred is sent to a fixing device where the toner image is fixed, and then sent from the image forming apparatus main body to the sheet processing apparatus.

(7) The sheet sent out from the image forming apparatus main body is re-punched by punching means in the sheet processing apparatus, and then discharged out of the apparatus. Drilling into sheets involves stacking multiple conveyed sheets,
There are a stationary hole punching method for simultaneously punching a sheet bundle in a stationary state and a moving hole punching method for punching a sheet being conveyed.

[0010]

In the above-mentioned conventional example,
The image forming operation on the sheet and the punching operation on the sheet are performed by the procedure of the above contents (1) to (7), but the steps (1) to (7) are performed. In order to punch a hole in a sheet, the sheet passes through a long transport path, and the position of the sheet is shifted in this transport path. When a punch hole is punched in the sheet in the process (7), In addition, in order to eliminate the displacement of the punching position, it is necessary to correct the position of the sheet or the punching means. Further, there is a problem that a correction device for correcting the position of the punched hole is required, thereby increasing the cost of the device and increasing the size of the device itself.

According to the present invention, there is provided an image forming apparatus capable of perforating a recording sheet or a punching means for perforating the recording sheet without adjusting a relative position of the recording sheet, thereby reducing the cost and size of the apparatus. It is intended to do so.

[0012]

The invention according to claim 1 is
Sheet feeding means for feeding the sheet, resist conveying means for temporarily stopping the sheet fed by the sheet feeding means, correcting the skew, and feeding the sheet at a proper timing, and the sheet conveyed by the resist conveying means An image forming apparatus for forming an image on a sheet, wherein a punching means for punching a punched hole in a sheet fed by the resist conveying means is provided near the downstream side of the resist conveying means. And

According to a second aspect of the present invention, there is provided a sheet detecting means in front of the conveying means for detecting presence or absence of a sheet, which is disposed near the upstream side of the resist conveying means, and a position for piercing the sheet by the perforating means. Punch position selecting means that can be selected at the front end or the rear end.

According to a third aspect of the present invention, there is provided a method for detecting the amount of sheet conveyance by the registration conveyance means, wherein the registration conveyance is performed when the punch position selected by the punch position selection means is a sheet leading end. Means for temporarily stopping the fed sheet based on the detection result of the sheet detecting means before the conveying means, correcting the skew, and then rotating the sheet by a predetermined amount after the sheet is detected by the sheet detecting means before the conveying means. The sheet is fed and stopped at a position where the punch by the punching means is possible at the leading end of the sheet.

According to a fourth aspect of the present invention, when the punch position selected by the punch position selecting means is a sheet rear end, the punching means is a rotary punching means comprising a rotatable punch and a die. A punch hole is formed in the sheet being conveyed by the resist conveying means.

According to a fifth aspect of the present invention, when the image formation on the sheet by the image forming means is a double-sided image formation, the punch position selecting means automatically determines a punching position by the punching means. The selection is made at the tip.

[Operation] Based on the above configuration, the sheet fed by the sheet feeding means is temporarily stopped by the resist conveying means to correct the skew, and furthermore, the punching means arranged near the downstream side of the resist conveying means. After the punch holes are punched, the sheet is sent to the image forming means at the timing of conveyance. This shortens the sheet conveyance path before performing the punching operation, which is a cause of the positional deviation of the sheet, eliminates the shift of the punching position, and reduces the sheet or punching hole conventionally required. A means for correcting the position of the means is not required, so that the cost can be reduced and the apparatus can be downsized.

[0018]

An embodiment of the present invention will be described below with reference to the drawings. First, an example of a general image forming apparatus to which the present invention can be applied will be described with reference to FIG.

In FIG. 1, reference numeral 1000 denotes an image forming apparatus main body. Reference numeral 900 denotes an upper cassette. Sheets P in the cassette are separated and fed one by one by the action of a separation claw (not shown) and a feeding roller 901, and are guided to a registration roller (register conveyance means) 906. Reference numeral 902 denotes a lower cassette. Sheets P in the cassette are separated and fed one by one by the action of a separating claw (not shown) and a feeding roller 903, and are guided to registration rollers 906. Reference numeral 904 denotes a manual guide, which guides the sheet P one by one to a registration roller 906 via a roller 905. Reference numeral 909 denotes a sheet stacking device (deck type)
The sheet P on the middle plate 909a is separated and fed one by one by the action of a feeding roller 910 and a separation claw, and the conveying roller 9
It is led to 11.

Reference numeral 912 is a photosensitive drum (image forming means), 913 is a reading optical system, 915 is a developing device, 91
Reference numeral 6 denotes a transfer charger, and 917 denotes a separation charger, and these constitute an image forming unit.

Reference numeral 921 denotes a conveying belt for conveying the sheet P on which an image has been formed, 922 denotes a fixing device, 923 denotes a conveying roller, and 925 denotes a flapper. The sheet P on which an image has been formed is guided to a discharge roller (discharge unit) 926 by a flapper 925 and is conveyed into a sorter 927. This sorter 927 has a non-sort tray 93
0a, sort bin tray 930b, non-sort tray discharge roller 930c, sort bin tray discharge roller 930
d, the non-sort tray 903a and the sort bin tray 930b move up and down to sort the sheets P one by one. In some cases, a discharge tray (sheet stacking means) may be mounted in place of the sorter 927.

Reference numeral 931 denotes an automatic document feeder.
Tray 931a, separation means 931b, return path 931
c, a discharge roller 931d and the like. The automatic document feeding device 931 causes the document D to be transferred one by one to the platen 932.
It is positioned above and read by the optical system 913. Reference numeral 933 denotes a transport belt that rotates the document D in the forward direction (in the direction of arrow 160) to guide the document D to the platen 932, and discharges the document D from the platen 932 in the reverse direction.

An image is formed on the photosensitive drum 912 in accordance with the set number of copies for one document D placed on the platen 932, and sheets P for the number of copies are formed.
Is fed from the cassette 900, 902 or the deck 909 each time an image is formed on the photosensitive drum 912. The registration between the image on the photosensitive drum 912 and the sheet P is performed by a registration roller 916.

When the required number of copies are formed, the original D is discharged from the platen 932, and the next original D is positioned on the platen 932. Hereinafter, the same operation is repeated.

Reference numeral 940 denotes an intermediate tray which is used to form an image on both sides of the sheet P, or
In the case of forming an image by superimposing on one side of (multiple), once,
The sheet P on which an image is formed is stocked.
Reference numeral 941 denotes a conveyance roller, 942 denotes a conveyance belt, 943.
Denotes a flapper, 945 denotes a transport belt, and 946 denotes a transport roller. For double-sided copy, pass 9
The sheet P is guided to the intermediate tray 940 by the discharge roller 948 through the sheet 47. The sheet P has an image surface facing upward. In the case of multiple copying, the sheet P is guided to the intermediate tray 940 through the path 949. The sheet P has an image surface facing downward.

Sheets P stacked on the intermediate tray 940
Is a pair of auxiliary rollers 950 and 951 and a pair of forward / reverse separation rollers 9
By the action of 52, the sheets are separated one by one from below and fed again. The re-feeded sheet P is transported by rollers 953 and
955, 956, roller 911, registration roller 90
6 to the image forming unit 920.

In accordance with the number of copies set for one document D placed on the platen 932, first, single-sided copies are made, and they are stacked on the intermediate tray 940. Thereafter, the document D on the platen 932 is turned upside down and guided on the platen 932 again, and this image is read by the number of copies. The read image is formed on a sheet P that is re-fed from the intermediate tray 940 every time the image is read. They are sorted by a sorter (sheet processing device) 930 in page order.

On the other hand, there is also a method in which only one copy of the original D is made each time the automatic original feeding device 931 makes one cycle. According to this method, even when making copies of a plurality of copies, a copy group having the same page order can be obtained in order.
Even without the sorter 930, the required number of copies can be obtained separately. When making a double-sided copy in this manner, both sides of one original D are continuously read, and both sides of the sheet P are continuously copied and ejected. If this is repeated many times, a divided double-sided copy group can be obtained.

Next, an embodiment of the present invention will be described in detail with reference to FIGS.

FIG. 1 shows an image forming section and a punch section of an image forming apparatus to which the present invention is applied, and FIG. 2 shows an electric block diagram of the present apparatus. 1 and 2,
Reference numeral 912 denotes a photosensitive drum (image forming means) on the surface of which an image is formed using toner, and 916 denotes the photosensitive drum 912.
, A transfer charger that transfers an image formed by the toner on the photosensitive drum 912 to the sheet P,
Reference numeral 3 denotes a sheet feeding port through which the sheet P enters the apparatus, and reference numeral 906 denotes a sheet feeding port between the sheet feeding port 103 and the transfer charger 916.
(Registration conveying means) for correcting the skew of the sheet P and conveying the sheet P mainly.
A sheet feeding roller (sheet feeding means) for sending out the sheet P of the sheet feeding port to the registration roller 906, a sheet feeding cassette 106 for storing a plurality of sheets P, Denotes a cassette paper feed roller for feeding the sheet P from the paper feed cassette 106 to the paper feed roller 105; 107a, a conveying roller; and 904, a manual feed tray.

Near the upstream side of the registration roller 906, a registration roller front sensor for detecting the presence or absence of the sheet P fed by the sheet feeding roller 105 is provided.
A punching device (punching means) 109 for punching a punched hole at the leading end of the sheet P is provided near the downstream side of the registration roller 906.

In FIG. 2, a control unit 201 is connected to the registration roller front sensor 108, a driving unit 202, and an operation unit 203, and controls all operations of the image forming apparatus. The driving means 202 is provided with the control means 201.
, The registration roller 906, the paper feeding roller 105, the cassette paper feeding roller 107, and the punching means 109 are driven. Operation means 20
Reference numeral 3 denotes a display unit that displays the number of sheets on which an image is formed, the current state of the image forming apparatus, and the like, and is used by an operator to operate the image forming apparatus.

The punch position selecting means 112 is a means for selecting the punch position of the punch device 109 for the sheet P at the leading end or the trailing end in the sheet conveying direction, and is operated by the user. Registration roller 11
The drive motor 3 is a pulse motor, and the amount of rotation is detected by a clock disk (not shown) that rotates integrally with the pulse motor and a clock sensor that detects the position of the clock disk. I have. The clock disk and the clock sensor constitute a rotation amount detecting unit 113 of the registration roller 906. The rotation amount detection unit 113 functions as a conveyance amount detection unit for the sheet P of the registration roller 906, and the control unit 201 controls the rotation operation of the registration roller 906 based on the detection amount. I have.

In the image forming apparatus configured as described above, the punching operation is performed as follows.

(I) When the image forming operation is started by the image forming apparatus main body 1000 by operating the operating means 203, the sheets P in the sheet feeding cassette 106
7, and is further fed by the paper feed roller 105 in the direction of the registration roller 906.

(II) The registration roller front sensor 108 is
It detects that the sheet P has been sent near the upstream side of the registration roller 906.

(III) The registration roller 906 corrects the skew of the sheet P by temporarily stopping the sheet P and forming a loop.

At this time, the control means 201
The following four processes (a) to (d) are performed according to the setting from (3).

FIG. 3 shows a processing procedure executed by the control means 201.

(A) When the re-punching is not set by the operation means 203 (step 1), the registration roller 9 is used until the preparation necessary for continuing the image forming operation is completed.
06, the sheet P is stopped (step 2), and after preparation is completed, the sheet P is sent to the transfer means 102 and the photosensitive drum 912 (step 3).

(B) When punching is set by the operation means 203 (step 1) and a double-sided image forming (double-sided printing) operation is being performed (step 4), the registration roller 906 moves the sheet P Is fed forward by an amount necessary to make a punched hole, and temporarily stopped (step 5).
A punch hole is made at the tip of the step (step 6). Sheet P
When the image formation on the sheet P is a two-sided image formation, the control unit 201 automatically selects the punch position on the sheet P so as to be the leading end. Then, the sheet P is stopped until the preparation necessary for continuing the image forming operation is completed (step 2), and after the preparation is completed, the sheet P is sent to the transfer unit 102 (step 3). The image formation on the back surface side of the sheet P is performed on the photosensitive drum 912 by exchanging the leading and trailing ends with the intermediate tray 940 shown in FIG.

(C) The punching is set by the operation means 203 (step 1), and the setting operation of the double-sided printing is not performed (step 4), and the punching position is set to the sheet P. Is selected (step 7), the registration roller 906 sends the sheet P forward (downstream) by an amount necessary for punching a punch hole and temporarily stops (step 5). 1
09 is driven to punch a hole at the leading end of the sheet P (step 6). Then, the sheet P is stopped until the preparation necessary for continuing the image forming operation is completed (Step 2),
After the preparation is completed, the sheet P is sent out to the transfer means 102 and the photosensitive drum 912 (step 3).

(D) The punching is set by the operation means 203 (step 1), and the double-sided printing operation is not performed (step 4), and the punching position is at the rear end of the sheet P. Selected (Step 7)
At this time, the sheet P is stopped until the preparation necessary for continuing the image forming operation is completed (step 8), and after the preparation is completed, the sheet P is sent to the transfer unit 102 (step 9). When the registration roller front sensor 108 does not detect the presence of the sheet P (step 10), it waits for a lapse of time until the rear end of the sheet P reaches a position where a punch hole is to be formed (step 11). Punch device 109
Is performed on the sheet P (step 12).

When the punch position on the sheet P is at the rear end, a rotary punch device is used as the punch device 109. This punch device includes a rotatable punch and a rotary punch. It is composed of a die having punch holes that rotate in synchronization with each other, so that punch holes can be formed in the sheet P being conveyed. When punching a hole at the leading end of the sheet P, the punching device is, in addition to the above-mentioned rotary type, a fixed type including a die having a punched hole in a fixed state and a punch which can move forward and backward with respect to the die. It may be a punch device. Further, when a punch hole is formed at the leading end of the sheet, the sheet once stopped by the resist conveying means is punched, so that the punch hole can be easily formed technically.

In the conventional image forming apparatus, as described above, the punching device that precedes the sheet P with a punch hole is:
Since the sheet P is provided in a sorter (which may be a sheet stacking tray) as the sheet processing apparatus shown in FIG. 4, the registration rollers 906 for correcting the skew of the sheet P and the transport path from the photosensitive drum 912 to the punching apparatus are provided. Long, sheet P
However, according to the present embodiment, as described above, the punch device 109 for punching the sheet P
Is located near the downstream side of the registration roller 906 and the transport path is short, so that the position of the sheet P with respect to the punch device 109 does not shift. Accordingly, a device for adjusting the position of the sheet P or the punch device 109 is not required, and the size of the device can be reduced.

[0046]

As described above, according to the present invention,
A punch hole punching means is provided immediately after the registration roller, and the punch hole punching operation is performed.Therefore, the sheet conveyance path until the punch hole punching operation, which is a factor of the sheet position shift in the punch hole punching means, is performed. This makes it possible to eliminate the gap in the position at which the punch hole is made, and to eliminate the cost disadvantage of having a means for correcting the position of the sheet or the punch hole means. Can be realized.

Further, in the case where a punch hole is formed at the leading end of the sheet, since the sheet once stopped by the resist conveying means is punched, the punch hole can be easily formed technically. Become.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional front view showing a main part of an image forming apparatus according to the present invention.

FIG. 2 is a block diagram related to control of the image forming apparatus.

FIG. 3 is a flowchart illustrating an operation of the image forming apparatus.

FIG. 4 is a vertical side view showing an example of an image forming apparatus to which the present invention can be applied.

[Explanation of symbols]

P sheet 105 paper feed roller (paper feed means) 108 sensor before registration roller (detection means before registration roller) 109 punch device (punching means) 112 punch position selection means 113 rotation amount detection means (sheet conveyance amount detection means) 201 Control means 906 Registration roller (registration conveyance means) 912 Photosensitive drum (image forming means) 926 Discharge roller (discharge means) 927 Sorter (sheet processing apparatus) 1000 Image forming apparatus main body

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takayuki Kawakami 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Yoshiyuki Suzuki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inside the corporation

Claims (5)

[Claims] A sheet feeder for feeding a sheet, a resist feeder for temporarily stopping the sheet fed by the feeder, correcting the skew thereof, and feeding the sheet at a proper timing; and the resist feeder. And an image forming means for forming an image on a sheet conveyed by the method. An image forming apparatus comprising: a punching means for punching a punched hole in a sheet sent out by the resist conveying means, near a downstream side of the resist conveying means; An image forming apparatus comprising: 2. A sheet detecting means in front of a conveying means, which is arranged near the upstream side of the resist conveying means and detects the presence or absence of a sheet, and a position at which a sheet is pierced by the piercing means is a leading end or a trailing end of the sheet. 2. The image forming apparatus according to claim 1, further comprising: a punch position selecting unit configured to select the punch position. 3. The method according to claim 1, further comprising: detecting a sheet conveyance amount by the registration conveyance unit. If the punch position selected by the punch position selection unit is a leading end of the sheet, the registration conveyance unit includes the conveyance unit. Based on the detection result of the preceding sheet detecting means, the fed sheet is temporarily stopped and skew correction is performed, and then the sheet is rotated by a predetermined amount after the sheet is detected by the conveying means front sheet detecting means, and the sheet is rotated by the punching means. 3. The image forming apparatus according to claim 2, wherein the sheet is fed to a position where the punch can be moved to a leading end of the sheet and stopped. 4. When the punch position selected by the punch position selecting means is a rear end of a sheet, the punching means is a rotary punching means comprising a rotatable punch and a die; 3. The image forming apparatus according to claim 2, wherein a punch hole is formed in the sheet being conveyed by the means. 5. When the image formation on the sheet by the image forming means is a double-sided image formation, the punch position selecting means automatically selects a punching position by the punching means at a sheet leading end. 3. The method according to claim 2, wherein
The image forming apparatus as described in the above.