JPH02138077A - Image forming device with intermediate tray - Google Patents

Abstract

PURPOSE:To obtain copied sheets correctly coinciding with the desired number by providing the first and second image forming means, a jam control means, and the first and second image formation control means. CONSTITUTION:When a jam of recording sheets occurs at the time of image formation by the second image formation control means based on the first image formation control means, a jam control means detects the jam, interrupts an image forming action, calculates the number of jammed sheets, and displays it. An operator releases the jam by removing the jammed sheets corresponding to the displayed number. The second image formation control means allows the first image forming means to perform the image forming action for the sheets removed at the time of jam release, and deficit recording sheets are replenished into an intermediate tray. The control by the first image formation control means is then restarted to obtain copied sheets of the desired number.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image forming apparatus, and particularly to an image forming apparatus in which an image forming section and an intermediate tray are connected between a paper feeding section and a paper discharging section. .

[Conventional technology]

2. Description of the Related Art Some conventional image forming apparatuses, such as copying machines, have an image forming section and an intermediate tray connected between a paper feed section and a paper discharge section, and are capable of forming images on both sides of each transfer sheet.

In this type of image forming apparatus, when copying a document,
First, a copy is made on the - side of the transfer paper supplied from the paper feed section, and the copy paper is stored in the intermediate tray. This copying operation is repeated for the desired number of copies. Subsequently, the original is replaced, a transfer sheet is fed from the intermediate tray, and after copying is performed again on the other side of the transfer sheet, the transfer sheet is discharged to the paper discharge section. This copying operation is also repeated for the desired number of copies. Through this series of operations, the desired number of double-sided copies can be obtained.

Here, if a jam occurs in the transfer paper when copying is performed again by feeding the transfer paper from the intermediate tray, the copying operation is temporarily stopped when the jam is detected. Next, after the operator clears the jam, a number of transfer sheets corresponding to the number of sheets lost due to the jam are fed from the paper feed section, copies are made on the negative side, and the sheets are stored in the intermediate tray. As a result, the desired number of transfer sheets with copies made on their sides is replenished. Subsequently, the original is replaced, and after copying the other side of the transfer paper remaining in the intermediate tray, including the replenishment, the transfer paper is discharged to the paper discharge section.

[Problems to be Solved by the Invention] In the conventional image forming apparatus described above, when an operator returns jammed transfer paper to the intermediate tray, or when transfer paper is fed in duplicate, it is difficult to remove the paper remaining on the intermediate tray. The image forming apparatus cannot accurately determine the number of sheets of transfer paper being used. Therefore, it is not possible to accurately feed the number of transfer sheets corresponding to the number of sheets lost due to the jam from the sheet feeding section. Therefore, in this image forming apparatus, the number of copies finally obtained may not match the desired number.

SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus having an intermediate tray that allows the number of copies to be finally obtained to accurately match the desired number of copies.

[Means to solve the problem]

An image forming apparatus having an intermediate tray according to the present invention is an image forming apparatus capable of forming an image on a recording sheet, in which an image forming section and an intermediate tray are connected between a paper feeding section and a paper discharging section. be. As shown in FIG. 1, this image forming apparatus has the following features:
The image forming apparatus includes a first image forming means, a second image forming means, a first image forming control means, a jam control means, and a second image forming control means.

The first image forming means is a means for forming an image on a recording sheet supplied from a paper feeding section in an image forming section and then storing the recording sheet in an intermediate tray. The second image forming means is a means for forming an image again on the recording sheet supplied from the intermediate tray in the image forming section, and then discharging the recording sheet to the paper discharging section. The first image forming control means is a means for causing the first and second image forming means to perform an image forming operation for a desired number of sheets. The jam control means detects a jam of the recording sheet during image formation by the second image formation means based on the first image formation control means, and interrupts the image formation operation by the first image formation control means; This is a means for calculating and displaying the number of jammed sheets. After the image forming operation is interrupted by the jam controlling means, the second image forming control means waits for the jam to be cleared and causes the first image forming means to perform an image forming operation for the number of bones removed when the jam is cleared. After that, it is a means for restarting control by the first image forming control means.

[Effect]

In an image forming apparatus having an intermediate tray according to the present invention,
Basically, the first image forming control means causes the first and second image forming means to perform image forming operations for a desired number of sheets.

Here, the first image forming means forms an image on the recording sheet supplied from the paper feeding section in the image forming section, and then stores the recording sheet in the intermediate tray. Further, the second image forming means forms an image again on the recording sheet supplied from the intermediate tray in the image forming section, and then discharges the recording sheet to the paper discharging section.

When a jam occurs in a recording sheet during image formation by the second image forming means based on the first image forming control means, the jam control means detects the jam and interrupts the image forming operation, and also controls the number of jammed sheets. Calculate and display. The operator sees the display and clears the jam by removing the number of jammed recording sheets corresponding to the display. In this case, the operator can reliably recognize the number of jammed recording sheets from the display and can accurately exclude only the jammed recording sheets.

Next, the second image forming control means causes the first image forming means to perform an image forming operation for the number of bones removed when the jam is cleared. In this case, since the operator has accurately removed the jammed recording sheets, the intermediate tray is accurately replenished with the missing recording sheets.

After that, the control by the first image formation control means is restarted,
Obtain the desired number of copies.

[Embodiment] In FIG. 2 showing an embodiment of the present invention, an automatic document feeder 11 that also serves as a document holder is provided at the top of a copying machine 10. On the right side of the copying machine 10, from the top, there are a bypass stand 12 and paper cassette cases 13, 14.
is located.

Further below, a large paper feed cassette case 16 is arranged. On the left side of the copying machine 10, there is an output tray 1.
5 is placed.

A photosensitive drum 17 is arranged approximately at the center inside the copying machine 10 . Around the photoreceptor drum 17, a charging device 18, a developing device 19, a transfer device 20, and a transfer paper separation device 2 are installed.
1 and a cleaning device 22 are arranged in this order. Further, in the upper space of the copying machine 10, an exposure device 23 of an optical system is provided.
is located. Furthermore, a paper feed conveyance path 24 is provided between the bypass table 12 and the like and the transfer device 20.

On the downstream side of the transfer device 20, there is a paper discharge conveyance device 2.
5 and a fixing device 26 are provided. A branch 27 is arranged between the fixing device 26 and the output tray 15, and the branch 2
A reversing device 28 is arranged above 7. Branch 27
The fixing device 26 can be switched between a first posture (the illustrated posture) in which the fixing device 26 is communicated with the discharge tray 15 and a posture in which the fixing device 26 is communicated with the reversing device 28 .

In the lower space of the copying machine 10, there is a lower paper feeding type intermediate tray 3.
0 is placed. A transfer paper conveyance path 31 is arranged between the left end of the intermediate tray 30 and the branch 27. A transfer paper conveyance path 32 is arranged between the right end portion of the intermediate tray 30 and the middle of the paper feed conveyance path 24 . The downstream end (upper end) of the transfer paper conveyance path 32 is connected to the transfer bag 2.
It is connected to the paper feed conveyance path 24 so as to smoothly continue to the 20 side.

The intermediate tray 30 includes a transfer paper table 33 extending generally horizontally.
, a paper feed roller 34 disposed at the right end of the transfer paper base 33 , and a feed roller 35 disposed at the center of the transfer paper base 33 on the right side. This feed roller 35 is
It also serves as a counter that counts the number of transfer sheets carried out from the intermediate tray 30. Above the feed roller 35,
A pressing roller 37 is arranged to press down the transfer paper placed on the transfer paper table 33 from above. This presser roller 37
also serves as a rotary switch for counting the number of sheets of transfer paper carried into the intermediate tray 30 through the transfer paper conveyance path 31.

The automatic document feeder 11 has a document table 42 on the right side of the housing 41, and stacked documents to be supplied are placed on the document table 42! ! 2. At the center of the upper part of the housing 41, a document discharge section 43 is provided where discharged documents are stacked and placed. At the bottom of the housing 41 is a conveyor belt 45 that is stretched between rollers arranged at intervals in the left and right direction.
is located. The lower end surface of the conveyor belt 45 faces a transparent contact glass 47 disposed at the upper end of the main body of the copying machine 10 . Furthermore, the exposure value of the exposure device 23?
1t29 is configured to be able to move in the left-right direction in the figure in order to expose the document placed between the conveyance belt 45 and the contact glass 47.

A paper feed roller section 48 is provided on the right side of the housing 41 for feeding documents one by one from the document table 42 to the conveyor belt 45 side. A document discharge path 49 is provided on the left side of the housing 41 for conveying the document from the conveyor belt 45 to the document discharge section 43 . Further, a document reversing path 50 is arranged between the downstream end of the conveyor belt 45 and the downstream end of the document ejection path 49, which allows the document to be reversed when a double-sided document is used. Paper can now be fed again.

The copying machine 10 has a control section (not shown) consisting of a microcomputer, a key panel, a liquid crystal display board, etc., and is controlled by it as will be explained later. Further, the copying machine 10 is provided with a limit switch 51 on the conveyance path between the branch 27 and the discharge tray 15 for counting the number of discharged transfer sheets. Intermediate tray 30
The transfer paper table 33 is provided with a pressure-sensitive switch 52 for determining whether or not there is any transfer paper remaining on the transfer paper table 33. Further, on the downstream side of the paper feed roller 34, a double feed detection sensor 53 is provided to detect double feed of transfer paper. This sensor 53 is composed of, for example, a light-emitting element and a light-receiving element, and is adapted to detect the presence or absence of double feeding from changes in the amount of light transmitted through the transfer paper (for example, see Japanese Patent Laid-Open No. 113076/1983). ), there are other sensors on the conveyance path of the transfer paper, such as sensors for detecting jams in the transfer paper, etc.
A general sensor (not shown) is attached. Further, the automatic document feeder 11 is equipped with a general sensor (not shown) such as a sensor for detecting the presence or absence of an unfed document. Each of these sensors is connected to the microcomputer.

Next, the operation of the above embodiment will be explained according to the flowcharts shown in FIGS. 3 to 5.

When a main switch (not shown) is turned on, the program shown in FIG. 3 starts. In step S1, the number of copies a
Initial settings such as setting 1 to 1 and setting the copy mode to single-sided original/single-sided copy mode are performed. Next, in step S2, key human power is awaited. When a key is input in step S2, the process moves to step S3.

In step S3, it is determined whether the input key is a copy number setting key. If it is the setting key for the number of copies, step S
4, the input number of copies is set as the number of copies a, and then the process returns to step S2.

In step S3, if the copy number setting key is not pressed, the process moves to step S5. In step S5, the input key is
Determine whether or not is a copy key.

If it is not a copy key, the process moves to step S6.

In step S6, other general processing is performed. Here, based on the input key, for example, switching of copy mode, setting of transfer paper size, etc. are performed. When the process is finished, the process returns to step S2.

Next, the copying operation will be explained in three modes: single-sided original/single-sided copy mode, single-sided original/double-sided copy mode, and double-sided original/both-sided copy mode.

- If the input key is a copy key in mode step S5, the process moves to step S7. In step S7, it is determined whether the set copy mode is a single-sided original/double-sided copy mode. If the single-sided original/double-sided copy mode is not set, the process advances to step S8. In step S8, it is determined whether the set copy mode is double-sided original/double-sided copy mode. If the double-sided original/double-sided copy mode is not set, the process advances to step S9.

If the determinations in step S7 and step S8 are both No, it means that the single-sided original/single-sided copy mode is set. Therefore, in step S9, the copying machine 10 is controlled as follows so that the copying operation is performed in the single-sided original/single-sided mode.

1 at the bottom of the downward facing originals stacked on the original table 42
The sheet is placed on the contact glass 47 by the paper feed roller section 48 and the conveyor belt 45. On the other hand, transfer paper of a predetermined size is sent to the transfer device 20 from either the bypass table 12 or the paper feed cassette case 13, 14 or 16. In the transfer device 20, the image of the document based on the exposure operation of the exposure device 23 is transferred onto transfer paper. Further, the transfer paper is sent to a fixing device 26 where it is fixed, and is then discharged to the discharge tray 15 through a branch 27. By performing this copying operation for the desired number of copies a, the desired number of copies can be obtained.

Repeat the same operation for subsequent manuscripts one after another,
When the copying operation is completed for all originals, step S
Return to 2.

- When the mode copy key is input, the copy mode is set to one-sided original or
In the double-sided copy mode, the operation is as follows.

Here, the process moves from step S7 to step SIO in FIG. 4. In step S10, an intermediate tray counter B for counting the number of transfer sheets carried into the intermediate tray 30 and an ejection counter C for counting the number of transfer sheets ejected to the ejection tray 15 are set to 0. be done.

Next, in step Sll, the automatic document feeder 11
The first document is fed. And step S
12, a bypass stand 12, a paper feed cassette case 1
One side of the specified transfer paper fed from 3, 14 or 16 (
The image of the document is copied onto the first page). These document feeding operations and image copying operations are similar to those in the single-sided original/single-sided copy mode described above. However, in this case,
Branch 27 is switched to the reversing device 2B side. Therefore,
The fixed transfer paper is reversed by the reversing device 2B and then placed on the transfer paper base 33.

In this copying operation, it is determined in step 313 whether or not a jam has occurred. If it is determined that no jam has occurred, the process moves to step S14. Step S1
In step 4, it is determined whether the rotation switch of the presser roller 37 is ON or not as the transfer paper passes. Pressing roller 37
While the transfer paper has not yet passed through the step S
The determination in step 13 is repeated to continue determining whether or not a jam has occurred. If a jam is detected in step S13, the process moves to step S15. In step S15, the process waits for the jam to be cleared, such as by the operator removing the jammed transfer paper. If the jam is cleared, the process returns to step S12 and the process in step S12 is repeated.

No jam occurs during copying operation, and presser roller 37
If the transfer paper passes through the portion safely, the transfer paper is placed on the transfer paper base 33 and the pressure sensitive switch 52 is turned on, and then the process moves to step 316. In step S16, the intermediate tray counter B is incremented, and then in step 317, the intermediate tray counter B is set to the desired copy number a.
Determine whether it is equal to or not. If this determination is No, the processes from step 312 to step S16 are repeated. That is, the processes from step 312 to step 316 are repeated until the desired number of copies of each original document is obtained. If the determination at step SIT is Yes, the process moves to step 31B.

In step S318, the intermediate tray counter B is set to 0, and in step S19, the document is discharged to the document discharge section 43.

By performing the processing from step Sll to this point, the processing for obtaining the desired number of copies of the first original is completed.

Next, in step S20, automatic document feeder 11
The second original is fed. And step S
At 21, transfer paper is fed from the intermediate tray 30 to the transfer device 20. This fed transfer paper is transferred to a reversing device 28.
Since the document has already been reversed in the transfer device 20, the image of the document is copied onto the other side (second side) of the transfer paper. These document feeding operations and image copying operations are basically the same as those in the single-sided original/single-sided copy mode described above. However, in this case, the branch 27 is switched to the discharge tray 15 side. Therefore, the transfer paper that has been fixed is transferred to the output tray 1 with images formed on both sides.
R is placed on top.

In this copying operation, it is determined in step S22 whether or not a jam has occurred. If it is determined that no jam has occurred, the process moves to step 323. Step S2
In step 3, it is determined whether the limit switch 51 is turned on by the passage of the transfer paper. While the transfer paper has not yet passed through the limit switch 51, step 322
Repeat the judgment in , and continue to judge whether or not a jam has occurred. If no jam occurs during the copying operation and the transfer paper passes safely through the limit switch 51, the process moves to step S24. In step S24, the ejection counter C is incremented, and then in step S25 it is determined whether or not the ejection counter C is equal to the desired number of copies a. While the determination in step S25 is No, that is, while the desired number of copies have not been completed, the processes from step S21 to step S24 are repeated.

Here, if no jam occurs during the copying operation of the second side, if the second side is copied on all the transfer sheets in the intermediate tray 30, a number of double-sided copies equal to the desired number of copies a will be made. A copy will be obtained.

As a result, the determination in step 325 becomes Yes, and the process moves to step 533 (described later).

On the other hand, if a jam is detected in step 322, step S
26. In step S26, it is first determined whether the cause of the jam is a paper jam or double feeding detected by the sensor 53. Further, the number of transferred sheets counted by the feed roller 35 and the number of sheets discharged to the tray 15 counted by the sensor 51 are compared. Based on these, the intermediate tray 30 and the paper output tray 1
Calculate how many sheets of transfer paper are staying between 5 and
It is memorized as the number of jam sheets. Next, in step 327, the number of jammed sheets is displayed on a display board (not shown) of the control unit based on the calculation result in step S26. This display is, for example, "Please remove sheet D."

Then, in step 328, the process waits until the jam is cleared, such as when the jammed transfer paper is removed by the operator. In this case, the operator can reliably recognize the number of jammed transfer sheets from the display on the display board, and can accurately exclude only the jammed recording sheets.

If the jam is cleared, the automatic document feeder 11 discharges the document to the document discharge section 43 in step S29. Next, in step S30, the value of [desired number of copies a, number of jammed sheets D] is substituted into the intermediate tray counter B. As a result, the difference between the desired number of copies a and the intermediate tray counter B becomes the number of transfer sheets that are insufficient as a result of the jam. In step 331, a message "Please return two originals" is displayed on the display board of the control unit to instruct the operator. Subsequently, in step S32, input of a copy key is awaited.

The operator moves the document output unit 43 according to the information on the display unit.
The two newest documents above are returned to the bottom end of the document table 42.

Then, if the operator presses the copy key, the program returns to step S11.

Next, the processes from step Sll to step 317 are performed again on the returned original, but in this case,
Since the intermediate tray counter B has already reached the value [desired number of copies a - number of jammed sheets D], the copying operation is repeated by the number of copies that are insufficient due to a jam during the copying operation of the second side. Therefore, when the determination in step S17 is Yes, it means that the intermediate tray 30 is replenished with the number of transfer sheets corresponding to the number of jammed sheets.

In this case, since the operator has correctly removed the jammed transfer paper, the intermediate tray 3
0 is accurately replenished with the missing amount of transfer paper.

After the processing in steps 31B and 319, in step 320, the second sheet of the returned originals is fed again. Then, the processes from step 321 to step 325 are repeated. At this point, the paper ejection counter C has already reached a value corresponding to the number of ejected transfer sheets before the jam processing, so the copying operation is repeated only for the remaining number of sheets. As a result, the output tray 15 has
The desired number of copies a of double-sided copies will be ejected.

Note that if a jam occurs during the re-copying operation from step 320 to step S25, the process from step S26 to step S32 is further performed, and then step S1 is performed.
The process of step S25 is performed again from l.

If the desired number a of double-sided copies are discharged onto the discharge tray 15 and the determination in step S25 is Yes, the process moves to step 333. In step S33, the paper discharge counter C is set to 0, and the process moves to step S334. In step S34, the document is discharged to the document discharge section 43. By performing the processing from step Sll to this point,
The process of obtaining the desired number of double-sided copies based on the two originals is completed.

Next, in step S35, it is determined whether there is a document on the document table 42 of the automatic document feeder 11.

If there is a document on the document table 42 of the automatic document feeder 11, the process returns to step Sll, and from step Sll to step 33.
The process in step 4 is performed on the next two originals. As a result, a desired number of double-sided copies based on the next two originals can be obtained. In step S35, automatic document feeder 1
If there is no original on the No. 1 original platen 42, the process returns to step S2 in FIG.

- When the copy mode is entered, the copy mode is set to double-sided original or
In the double-sided copy mode, the operation is as follows.

Here, the process moves from step S8 in FIG. 3 to step S40 in FIG. Step S40 to Step S48
The processing from step SlO to step 318
Since the process is the same as that described above, the explanation will be omitted here. When the processing from step S40 to step 348 is completed, the processing for obtaining the desired number of copies of the first side of the first document is completed.

In this double-sided original/double-sided copy mode, since the original supplied to the automatic document feeder 11 is a double-sided original, the original is reversed in step S49. The document whose first surface is placed on the contact glass 47 side is conveyed to the document discharge path 49 by the circulation of the conveyor belt 45, further conveyed to the document reversal path 50, and returned onto the contact glass 47 again. By this conveyance operation, the document is reversed, and its second surface is placed on the contact glass 47 side.

When the document reversing operation is completed, the process moves to step S50. The processing from step S50 to step S54 is as follows:
Since the processing is the same as the processing from step S21 to step 325, the explanation will be omitted here.

If a jam occurs in the second side copying operation, the program moves from step 351 to step 355 because there is a shortage of transfer paper on which the first side has been copied.

The processing from step S55 to step S57 is the same as the processing from step 326 to step 32B, so a description thereof will be omitted here. In this case as well, since the number of jammed sheets is calculated and displayed, the operator can reliably recognize the number of jammed recording sheets from the display and can accurately exclude only the jammed recording sheets. . In step 35B, the document is inverted again using the document inversion path 50, and its first surface is placed on the contact glass 47 side.

Next, in step 359, the intermediate tray counter B
Substitute the value of [desired number of copies a - number of jammed sheets D] into .

As a result, the desired number of copies a and the intermediate tray counter B
The difference between the number and the number of transfer sheets is the number of sheets of transfer paper that is insufficient due to a jam. Note that in the case of a double-sided document, the document can be reversed using the document reversing path 50, so there is no need for the operator to return the document to the document table 42. Therefore, in this case, the process subsequently returns to step S41 without waiting for an instruction from the operator.

The subsequent processing is performed in the same manner as the corresponding processing in the single-sided original/double-sided copy mode described above. However, step S4
The difference is that the original is reversed in step 9. Also in this case, since the jammed transfer paper is accurately removed by the operator, the intermediate tray 30 is accurately replenished with the missing transfer paper. Therefore, the number of copies finally obtained can be made to exactly match the desired number.

[Other Embodiments] The present invention can be similarly applied to a copying machine having a function of copying images of a plurality of originals on one side of transfer paper, that is, a composite copying function.

This type of copying machine generally has means for storing the transfer paper in an intermediate tray without inverting the transfer paper after fixing the image. When performing composite copying, this means is used to perform multiple copies on one side of the transfer paper. In this case, even if a jam occurs during the second or subsequent copying operation, by employing the present invention, the number of composite copies finally obtained can be made to accurately match the desired number of copies.

〔Effect of the invention〕

According to the image forming apparatus having the intermediate tray according to the present invention, the jam control means detects the jam and interrupts the image forming operation, and also calculates and displays the number of jammed sheets.
A jammed recording sheet can now be accurately removed by an operator.

As a result, the intermediate tray is accurately replenished with the missing recording sheets, and the number of copies finally obtained can be exactly matched to the desired number.

[Brief explanation of the drawing]

FIG. 1 is a block diagram corresponding to the present invention, FIG. 2 is a schematic vertical cross-sectional view of an embodiment of the present invention, and FIGS. 3, 4, and 5 are control flow charts of the embodiment. 12... Bypass stand, 13, 14. 16... Paper cassette case, 15... Ejection tray, 20... Transfer device, 30... Intermediate tray, 35... Feed roller, 3
7... Holder roller, 51... Limit switch, 5
3...Double feed detection sensor.

Claims (1)

[Scope of Claims] An image forming apparatus capable of forming an image on a recording sheet, in which an image forming section and an intermediate tray are connected between a paper feeding section and a paper discharging section, the paper feeding section a first image forming means for storing the recording sheet in an intermediate tray after forming an image on the recording sheet supplied from the intermediate tray; a second image forming means for ejecting the recording sheet to the paper ejecting section after forming an image again in the image forming section; and causing the first and second image forming means to perform an image forming operation for a desired number of sheets. When forming an image by a first image forming control means and the second image forming means based on the first image forming control means, a jam of the recording sheet is detected and the first image forming control means forms an image. a jam control means for interrupting the operation and calculating and displaying the number of jammed sheets; and after the image forming operation is interrupted by the jam control means;
Waiting for the jam to be cleared, causing the first image forming means to perform an image forming operation for the number of sheets removed at the time of clearing the jam, and then restarting control by the first image forming control means for forming a second image. An image forming apparatus having an intermediate tray comprising a control means.