JP2002149033A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of preventing a wasteful image from being formed by suitably managing a number of images. SOLUTION: A control part in a main body receives an enable/disable signal of copy from a managing device and judges whether that signal is a copy enable signal or not (S401 and S403). When that signal is not a copy enable signal, copy operation is stopped at timing to transmit image data from the control part to an image forming part (S413). When the signal from the managing device is a copy enable signal, a printing command is transmitted to the image forming part and a count signal on a number of images to be copied is transmitted to the managing device (S405 and S407). Then, image data are transmitted from the control part to the image forming part, image formation is performed on the basis of these image data and the formation of image is finished (S409).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an image forming apparatus, and more particularly, to an image forming apparatus capable of counting the number of copies and controlling a copying operation according to the counted number.

[0002]

2. Description of the Related Art Conventionally, some image forming apparatuses such as a copying machine have a management device for managing the number of copies. In such a management apparatus, counting is performed according to the sheet feeding timing of the copy sheet, and the number of copies is managed.

For example, a sensor is provided in the vicinity of a paper feed cassette to detect a copy paper fed by the sensor. Then, each time it is detected, the number of fed sheets is counted. When the counted number of fed sheets reaches a predetermined value, the copying operation is stopped before the next copy sheet is fed. That is, all the copy operations are stopped at the timing when the feeding of the copy sheet from the sheet cassette is started.

For this reason, no new copy paper is supplied from that point, and the image forming operation of forming a toner image on the photosensitive member is not performed. As described above, in the conventional copy number management apparatus, the copy number is counted based on the number of copy sheets supplied, and the copy operation is stopped at the copy sheet supply start timing.

[0005]

However, according to the conventional management apparatus in which the copying operation is stopped at the timing of feeding the copy sheet, useless image formation may be performed.

That is, in a color image forming apparatus having an intermediate transfer belt, for example, a copy sheet is fed from a sheet feed cassette at a timing when an image is formed on a photosensitive member with a color toner. It is earlier than timing.

That is, the image formed on the photoreceptor is transferred to an intermediate transfer belt, and the image is transferred to copy paper. For this reason, usually, the timing for feeding the copy paper from the paper feed cassette in order to match the transfer timing is late, and the image formation on the photoconductor and the intermediate transfer belt is started first.

In such an image forming apparatus, if the copy operation is stopped at the paper feed timing by controlling the number of sheets, an extra image is formed on the photosensitive member and the intermediate transfer belt. This extra image is cleaned without being transferred to the sheet. Therefore, waste occurs in the image forming operation and the toner used for the image forming.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an image forming apparatus capable of preventing a useless image from being formed by appropriately managing the number of sheets. That is.

[0010]

According to one aspect of the present invention, there is provided an image forming apparatus comprising: an image forming unit configured to form an image on a photoreceptor; Transfer means for transferring to paper, paper feeding means for feeding paper, count means for counting the number of sheets on which an image has been transferred by the transfer means, and whether or not the counted number has reached a predetermined value. Determining means for determining, and stopping means for stopping the image forming operation of the image forming means and the sheet feeding operation of the sheet feeding means at a predetermined timing when it is determined that the predetermined value has been reached, If the timing at which image formation is started by the imaging unit is earlier than the timing at which paper feeding is started by the paper feeding unit, the predetermined timing is:
The timing is before the start of image formation.

According to the present invention, the number of images transferred by the image forming means to the sheet is counted. When the counted number of sheets reaches a predetermined value, the timing at which image formation is started is earlier than the timing at which paper feeding is started, and the timing before image formation is started. At the timing, the image forming operation and the paper feeding operation are stopped.

For this reason, even when the image formation timing is earlier than the paper supply start timing as in a copying machine using an intermediate transfer belt, for example, the image forming operation and the supply Since both the paper operation and the paper operation are appropriately stopped, there is no waste of toner due to useless image forming operation and unnecessary paper feeding operation.

Accordingly, it is an object of the present invention to provide an image forming apparatus capable of preventing a useless image from being formed by appropriately managing the number of sheets.

Preferably, the timing before the start of image formation is a timing at which image data is transmitted to the image forming means.

According to this, when the count value reaches the predetermined value, the image forming operation and the sheet feeding operation are stopped at the timing when the next image data is transmitted to the image forming means. Therefore, it is possible to reliably and easily prevent useless image forming operation and sheet feeding operation.

Preferably, when the timing at which paper feeding is started by the paper feeding means is earlier than the timing at which image formation is started by the image forming means, the predetermined timing is:
This is characterized in that the timing is before the start of sheet feeding.

According to this, when the counted number of sheets reaches a predetermined value, the image formation starts when the image formation start timing is earlier than the sheet feeding start timing. The image forming operation and the paper feeding operation are stopped at a timing before the printing is performed.If the timing at which the paper feeding is started is earlier than the timing at which the image forming is started, the feeding is performed. At a timing before the start, the image forming operation and the paper feeding operation are stopped.

For this reason, for example, as in a copying machine using an intermediate transfer belt provided with a plurality of paper feed cassettes having different lengths of the paper feed path, the start timing of the paper feed and the operation depend on the paper feed cassette to be used. Even if the earlier start timing of the image is different, the image forming operation or the like is appropriately stopped in consideration of the earlier timing. For this reason, waste of toner due to useless image forming operation and unnecessary paper feeding operation are not performed.

[0019]

Next, embodiments of the present invention will be described in detail with reference to the drawings.

(First Embodiment) FIG. 1 is a schematic sectional view showing the entire configuration of an image forming apparatus 100 according to a first embodiment of the present invention. As shown in FIG. 1, the image forming apparatus 100 mainly includes a plurality of image forming units 1 for forming images, and collectively prints each image formed by the plurality of image forming units 1 as a full-color image on a copy sheet. And an intermediate transfer belt 11 for temporarily transferring the image, a sheet supply cassette 17 for supplying a copy sheet 14, a fixing device 30 for fixing an image transferred to the copy sheet, and an image forming apparatus. Unit 1
And the like, and a management device 200 for managing the number of copies.

The image forming unit 1 has a black (B)
K), yellow (Y), magenta (M), cyan (C)
Are provided to form the four color toner images, and each includes a charging unit 3, an exposing unit 9, a developing unit 4, and a cleaning unit 5.

The charging section 3 charges the photosensitive member 2 uniformly. The exposure unit 9 exposes the charged photoconductor 2 based on a control signal from the control unit 107. The developing unit 4 develops the electrostatic latent image on the photoconductor 2 formed by the exposure performed by the exposing unit 9 using toner of each color.

The toner image developed by the developing unit 4 is
The primary transfer is performed by the primary transfer unit 12 on the intermediate transfer belt 11. After the primary transfer, the toner remaining on the photoconductor 2 is removed by a cleaning unit 5 arranged downstream.

The intermediate transfer belt 11 rotates in a direction indicated by a white arrow. For this reason, each time the image forming unit 1 passes through the primary transfer section 12, the toner image of each color on the photoconductor 2 is sequentially superimposed on the same predetermined area of the intermediate transfer belt 11 from the upstream side. Then, a full-color toner image is finally formed on the intermediate transfer belt 11.

Then, further downstream, the so-called 2
In the next transfer unit 13, the full-color toner image is collectively transferred to the copy paper 14. Copy paper 14
First, the paper is stored in a paper feed cassette 17 and is conveyed one by one from there to the transfer unit 13 in accordance with the transfer timing. The copy paper 14 to which the full-color toner image has been transferred passes through the upper fixing device 30 so that the toner image is fixed, and is discharged onto the discharge tray 16.

The toner remaining on the intermediate transfer belt 11 after the secondary transfer is removed from the intermediate transfer belt 11 by the cleaning blade 15, conveyed by a conveying screw (not shown), and collected in a waste toner container (not shown).

The control device 107 receives a user input from the operation panel 109 and controls the image forming apparatus 100.
Performs overall control. Then, a control signal corresponding to the image is transmitted to the exposure unit 9 in order to drive the exposure unit 9. In addition, data is exchanged with the copy number management device 200 via the interface 111.

FIG. 2 is a functional block diagram showing the entire configuration of the image forming apparatus 100 according to the first embodiment of the present invention. Referring to FIG. 1, image forming apparatus 100 includes image forming unit 101, control unit 107, and operation unit (operation panel).
109, a main body including an interface (I / F) 111, and a management device 200.

The image forming unit 101 forms an image on the photosensitive member 2 and feeds a copy sheet to transfer the image onto the sheet at a predetermined timing. Image forming unit 10 for transferring to transfer belt 11
5 is included. The control unit 107 controls each unit in the image forming apparatus 100.

The timing at which paper feeding is started by the paper feeding unit 103 (paper feeding timing) and the timing at which image formation is started by the image forming unit 105 (image forming timing) are controlled by the control unit 107. The control unit 107 counts the number of times an image is formed on a sheet as the number of copies, and transmits the count signal to the management device 200 via the interface 111.

The management device 200 includes a control unit 215 for receiving a count signal and determining whether or not copying is possible, and a control unit 21.
5 includes an interface unit (I / F) 213 which is an interface for transmitting a judgment result from the main unit 5 as a copy permission / non-permission signal to the main unit and receiving a signal from the main unit.

Next, the processing operation of the image forming apparatus 100 will be described with reference to FIGS.

FIG. 3 is a flowchart showing the flow of the entire copy operation in the image forming apparatus 100.
FIG. 4 is a flowchart of the print number counting process (step S
It is a flowchart which shows the detail of 307). And
FIG. 5 is a flowchart showing the flow of the process of managing the number of copies in the management device 200.

Referring to FIG. 3, first, at step S301
The user operates the operation unit 109 to set the copy mode. Specifically, modes such as a photo mode, a character mode, and an automatic mode are set.

When the copy mode is set, step S
In step 303, the copy is started, that is, the reading operation of the document is started, and in step S305, the reading operation is actually performed.

When the reading of the document image is completed, a printing process and a counting process of the number of sheets are performed in step S307. Details of this processing will be described later. When an image is formed in step S307 and the image is fixed on the copy sheet 14, step S30
At 9, the printed copy paper 14 is ejected.

Next, details of the print / sheet number counting process in step S307 will be described with reference to FIG.
First, the control unit 107 of the image forming apparatus 100 receives a copy enable / disable signal from the management apparatus 200 via the interface 111 in step S401.
Then, in step S403, it is determined whether or not the received signal from management device 200 is a copy-permitted signal.

If the signal is not a signal indicating that copying is possible, that is, if the signal transmitted from the management device 200 is a signal indicating that copying is not possible, the copying operation is stopped in step S413. That is, here, transmission of image data from control unit 107 to image forming unit 105 (reading of image data)
Is stopped, the copy operation is stopped. Therefore, in this case, no image is formed on the photoconductor 2 in each image forming unit 1.

On the other hand, if it is determined in step S 403 that the signal from the management device 200 is a signal indicating that copying is permitted, a print command is transmitted from the control unit 107 to the image forming unit 105 in step S 405. .

In step S 407, a count signal of the number of copies is transmitted from the control unit 107 to the management device 200 via the interface 111.

In step S409, image data is transmitted from the control unit 107 to the image forming unit 105, and an image is formed based on the transmitted image data. When the image formation is completed, the copy sheet 1 is
When the image is transferred to No. 4, in step S411,
It is determined whether there is next image data.

If there is the next image data, the process returns to step S401, and the above series of processes is repeated. On the other hand, if there is no next image data, the subroutine ends, and the routine goes to the processing of step S309 in FIG.

According to the process shown in FIG. 5, the management device 200 always transmits a copy permission / prohibition signal to the control unit 107 of the image forming apparatus 100 main body.

Referring to FIG. 5, upon receiving a count signal from control unit 107 of the main body in step S501, management apparatus 200 counts the number of copies in step S503. That is, the number of copies is incremented by one in response to the count signal transmitted in step S407 of FIG.

Next, in step S505, the preset number of copies is compared with the number of copies counted in step S503, and it is determined whether the number of copies has reached the limit.

If the number of copies has not reached the limit, that is, if the limit is larger than the number of copies ("Yes" in step S505), step S50 is executed.
At 7, the control unit 215 generates a copy permission signal. On the other hand, if it is determined in step S505 that the number of copies has reached the control number (“No” in step S505), the controller 215 is determined in step S509.
Generates a copy disable signal.

As described above, in step S 507 or S 509, when a copy permission or non-permission signal is generated from the control unit 215, the interface unit 21
3 is transmitted to the control unit 107 of the image forming apparatus 100 main body. Then, the process returns to step S501 again, and the above process is repeated.

As described above, according to the image forming apparatus 100 of the present embodiment, the count signal transmitted from the control unit 107 of the image forming apparatus 100
The control unit 215 of the management apparatus 200 counts the number of copies and always determines whether the counted number of copies reaches a predetermined limit number. Then, when it is determined that the number of copies has reached the limit, a copy prohibition signal is immediately transmitted to the main body of image forming apparatus 100.

For this reason, the control unit 107 of the main body, which always receives the copy permission / non-permission signal from the management device 200 or at an appropriate timing, immediately stops the copy operation upon receiving the copy permission signal. be able to. That is, in the image forming unit 105, the image forming operation is stopped at the timing when the print command is transmitted from the control unit 107 to the image forming unit 105.

In the related art, the copying operation is stopped at the sheet feeding timing of the sheet feeding unit 103. For this reason, in a copying machine or the like in which the image forming timing is earlier than the sheet feeding timing, an image is formed in the image forming unit 105 before the sheet feeding timing, and the toner and the image forming operation are wasted. .

However, in the image forming apparatus 100 according to the present embodiment, the copying operation is stopped at an image forming timing earlier than the sheet feeding timing, so that a situation in which a useless image is formed can be avoided. .

In the present embodiment, the example in which the management device 200 is installed inside the image forming apparatus 100 has been described, but the present invention is not limited to such a configuration. Therefore, the management device 200 may be installed outside the image forming apparatus 100. Here, the number of copies is counted in the management device 200, and whether or not copying is permitted is determined based on the counted number. However, for example, the control unit 107 of the image forming apparatus 100 may count the number of copies, and the management apparatus 200 may determine whether or not copying is possible.

In FIG. 4, the timing at which the print command is transmitted from the control unit 107 to the image forming unit 105 is set as the timing at which the copy operation is stopped. However, if the timing is before the image data is transmitted,
The timing may be any timing. For example, the image forming operation may be stopped not at the print command transmission timing but at the timing at which the image data is transmitted.

(Second Embodiment) Next, a second embodiment of the present invention will be described. FIG. 6 is a schematic cross-sectional view illustrating an entire configuration when a charging device 600 is installed in an image forming apparatus 700 according to the second embodiment of the present invention.

Referring to FIG. 10, image forming apparatus 700 includes:
The configuration is substantially the same as that of the image forming apparatus 100 according to the first embodiment. However, here, the image forming apparatus 1
In place of the management device 200 provided in the image forming apparatus 00, the charging apparatus 600 is provided outside the image forming apparatus 700 and the paper feed cassette 17 is provided in a plurality of levels (five levels). This is different from the image forming apparatus 100 according to the first embodiment.

Image forming apparatus 700 in the present embodiment
Is almost the same as that of the image forming apparatus 100.
However, here, since the paper feed cassettes 17 are provided in a plurality of stages, the first and second paper feed routes (the route from the paper feed cassette 17 to the secondary transfer unit 13) are short.
The paper feed timing is later than the image forming start timing by the image forming unit 1. However, as for the third to fifth paper feed cassettes, the paper feed path is long, so that the paper is fed from the paper feed cassette at the timing when the image forming process is started by the image forming unit 1. Timing.

Therefore, whether to stop the copying operation at the timing at which the image forming operation in the image forming unit 1 is started or at the timing at which the paper 14 is fed from the paper feed cassette is determined at that time. Will differ depending on the paper feed cassette used.

FIG. 7 is a functional block diagram showing the overall configuration of an image forming apparatus 700 and a charging apparatus 600 according to the second embodiment of the present invention. Referring to this figure, image forming apparatus 700 includes image forming section 101 for forming an image on a copy sheet, control section 707 for controlling image forming apparatus 700 as a whole, and an apparatus for receiving an input from a user. An operation unit 109 includes an interface (I / F) unit 111 that is an interface between the image forming apparatus 700 and the billing apparatus 600.

The charging device 600 includes a control unit 615 for performing a charging process according to the number of copies, and an interface unit 613 which is an interface between the charging device and the image forming apparatus.

In the present embodiment, the billing device 600 is installed outside the image forming apparatus 700. However, the present invention is not limited to such a structure. As shown in the image forming apparatus 100 according to the embodiment, the charging apparatus 60 is provided inside the image forming apparatus 700.
0 may be provided.

Next, the processing operation of the image forming apparatus 700 according to the present embodiment will be described with reference to FIGS. The flow of the entire copy operation is the same as the flow chart shown in FIG.

FIG. 8 is a diagram showing the image forming apparatus 700 shown in FIG.
Print processing and number counting processing (step S3
It is a flowchart which shows the detail of 07). FIG.
Corresponds to the image forming process of FIG. 8 (steps S809 and S8).
It is a flowchart which shows the detail of 15). FIG.
8 (steps S811, S81)
It is a flowchart which shows the detail of 3). And FIG.
1 is a flowchart illustrating a flow of a billing process in the management device 600.

Referring to FIG. 8, control section 707 of image forming apparatus 700 determines in step S801 that charging apparatus 6
The balance information and the copy unit price information from 00 are received.
In step S803, the number of copies that can be made is determined from the received information.

Next, in step S805, the set copyable number and the actual copy number are compared. That is, it is determined whether the number of copies has reached the number of copies that can be made.

If the number of copies has reached the number of copies that can be made ("No" in step S805), the copying operation is stopped in step S821. That is, the copy operation, that is, the sheet feeding operation and the image forming operation in the image forming unit 101 are stopped at the timing when the image forming operation is started or the sheet feeding operation is started, whichever is earlier. Is done. Therefore, useless paper feeding and useless image formation are not performed.

On the other hand, if it is determined in step S805 that the number of copies has not reached the allowable number of copies ("Yes" in step S805), the process advances to step S807 to determine whether the image forming process is earlier than the sheet feeding process. A decision is made.

That is, when the first-stage or second-stage paper feed cassette of the image forming apparatus 700 of FIG. 6 is used, paper is fed later than the image forming unit 1 forms an image. Because the paper is printed, the image formation is faster than the paper feeding. On the other hand, when the third to fifth paper cassettes are used, the image forming unit 1 forms an image because the transport path from the paper cassette 17 to the secondary transfer unit 13 is long. The paper feed timing for feeding the paper is earlier than the start timing. Therefore, in this case, paper feeding is faster than image formation.

If it is determined in step S807 that the image formation is earlier than the paper supply, the image formation processing is performed in step S809, and then the paper supply processing is performed in step S811. On the other hand, if it is determined in step S807 that the image formation is not earlier than the sheet feeding, the image forming process is performed in step S815 after the sheet feeding process is performed in step S813.

After the image forming process and the sheet feeding process are performed as described above, a count signal is transmitted to billing device 600 in step S817. Then, in step S819, the presence or absence of the next image data is determined. If there is the next image data, the process returns to step S805, and the subsequent processes are repeated again. On the other hand, if there is no next image data, the subroutine ends and the process proceeds to step S309 in FIG.

Step S809 or step S815
As shown in FIG. 9, the image forming process of
At 01, a print command is transmitted from the control unit 707 to the image forming unit 105 of the image forming unit 101.

Next, in step S 903, image data is transmitted from the control unit 707 to the image forming unit 105, and image forming processing in the image forming unit 105 is started. Then, in step S905, the number of copies is counted. That is, the number of copies is incremented by one.

Next, step S811 or step S8
In the paper feed process in step 813, as shown in FIG. 10, first, a paper feed command is transmitted from the control unit 707 to the paper feed unit 103 of the image forming unit 101 in step S1001. Then, in step S1003, the feeding of the sheet 14 is started in response to the transmission of the sheet feeding command.

As shown in FIG. 11, the billing device 600
The count signal is received from the control unit 707 of the image forming apparatus 700 (S1101), and in step S1103, the balance information is updated. That is, the amount to be subtracted from the current balance is calculated based on the number of counts, the size of the copy sheet, and the like, and the balance information is updated based on the calculation result. Then, the process returns to step S1101 again.

As described above, in billing apparatus 600,
Upon receiving the count signal from image forming apparatus 700, the balance information is always calculated and updated. Then, the updated information is transmitted to image forming apparatus 700.

As described above, according to the image forming apparatus 700 of the present embodiment, even when the image forming timing and the paper feed timing are different depending on the paper feed cassette, copying is performed at an earlier timing. Operation is stopped. Therefore, it is possible to prevent a situation where an extra image forming operation or an extra paper feeding operation is performed.

In the present embodiment, as described with reference to FIG. 11, charging apparatus 600 performs only the process of updating the balance information. However, as in the management device 200 according to the first embodiment, a count process or the like may be performed.

The embodiments disclosed this time are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view illustrating an entire configuration of an image forming apparatus 100 according to a first embodiment of the present invention.

FIG. 2 is a functional block diagram illustrating an overall configuration of the image forming apparatus 100 according to the first embodiment of the present invention.

FIG. 3 is a flowchart illustrating a flow of a process of an entire copy operation in the image forming apparatus.

FIG. 4 is a flowchart illustrating details of a print process and a sheet count process (step S307) in FIG. 3;

FIG. 5 is a flowchart showing a flow of processing for managing the number of copies in the management apparatus 200.

FIG. 6 is a schematic cross-sectional view illustrating an overall configuration when an accounting device 600 is installed in an image forming apparatus 700 according to a second embodiment of the present invention.

FIG. 7 is a functional block diagram illustrating an overall configuration of an image forming apparatus 700 and a charging apparatus 600 according to a second embodiment of the present invention.

FIG. 8 is a flowchart illustrating details of the print processing and the sheet count processing (step S307) in FIG. 3 in the image forming apparatus 700.

FIG. 9 is a flowchart illustrating details of the image forming processing (steps S809 and S815) of FIG. 8;

FIG. 10 is a flowchart illustrating details of a sheet feeding process (steps S811, S813) in FIG. 8;

FIG. 11 is a flowchart showing a flow of a billing process in the management device 600.

[Explanation of symbols]

1 image forming unit, 2 photoreceptor, 3 charging section, 4
Developing section, 5 cleaning section, 9 exposure section, 11 intermediate transfer belt, 12 primary transfer section, 13 secondary transfer section, 1
4 recording paper, 16 paper output trays, 17 paper feed cassettes, 30 fixing devices, 100, 700 image forming devices,
101 image forming unit, 103 sheet feeding unit, 105 image forming unit, 107, 215, 615, 707 control unit, 109
Operation unit (operation panel), 111, 213, 613 Interface (I / F) unit, 200 management device, 600
Billing device.

Continued on the front page (72) Koji Tanaka, Inventor Koji Tanaka 2-3-13, Azuchi-cho, Osaka City Osaka International Building Minolta Co., Ltd. (72) Inventor Shoji Imaizumi 2-3-1, Azuchi-cho, Chuo-ku, Osaka City Osaka International Building Minolta Co., Ltd. (72) Inventor Tomokazu Kato 2-13-13 Azuchicho, Chuo-ku, Osaka City Osaka International Building Minolta Co., Ltd. F-term (reference) 2C061 AQ06 AR01 HH01 HH03 HJ06 HK11 HK15 HK21 HN22 2H027 DA45 DA50 DC03 DC05 DE07 ED17 ED30 EJ06

Claims (3)

[Claims] An image forming unit that forms an image on a photoconductor, a transfer unit that transfers the formed image to a sheet, a sheet feeding unit that feeds the sheet, and a transfer unit that transfers the image. Counting means for counting the number of sheets on which an image has been transferred; determining means for determining whether the counted number has reached a predetermined value; and when the determining means determines that the predetermined value has been reached. ,
Stopping means for stopping the image forming operation of the image forming means and the sheet feeding operation of the sheet feeding means at a predetermined timing; The image forming apparatus according to claim 1, wherein the predetermined timing is a timing before the start of image formation when the timing is earlier than a timing at which paper feeding is started by the means. 2. The image according to claim 1, wherein the timing before the start of the image forming is a timing at which image data is transmitted to the image forming unit. Forming equipment. 3. When the timing at which paper feeding is started by the paper feeding means is earlier than the timing at which image formation is started by the image forming means, the paper feeding is started at the predetermined timing. 3. The image forming apparatus according to claim 1, wherein the timing is earlier than the timing.