JP2013010608A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To raise the possibility that an error is resolved by retry of paper feeding when the error without paper feeding occurs, thus reducing a wasteful apparatus stop time due to occurrence of a jam without paper feeding.SOLUTION: An image forming apparatus includes: a control unit that when the paper is fed, rotates a paper feed roller in a state that a top surface of the paper stacked on a paper stack plate is brought into contact with the paper feed roller, and determines whether the paper non-feed error occurs based on an output signal of a paper feed sensor. When the control unit determines that the paper non-feed error occurs, for refeeding the paper, the unit once lifts up the paper stack plate, lifts down it again by controlling a lifting mechanism, and rotates the paper feed roller again.

Description

 The present invention relates to an image forming apparatus.

  Conventionally, in an image forming apparatus such as a copying machine or a multifunction peripheral, when a no-feed error occurs when feeding from a paper feed cassette or a manual feed tray, the paper feed operation is retried and the retry is performed a specified number of times. If the no paper feed error is not resolved, the printing operation is stopped and a screen for notifying the user of the occurrence of no paper feed JAM is displayed.

  In Patent Document 1 below, when a no-feed error occurs when a document is fed from a supply tray of a document reading device mounted on an image forming apparatus, the supply tray is lifted by a predetermined angle to detect a no-feed error. Techniques that attempt to resolve are disclosed.

JP 2006-89152 A

  As described above, conventionally, when a no-feed error occurs, only the retry of feeding operation, that is, rotation control of the feed roller is repeated, and this hardly changes the paper stacking state. It is unlikely that the error will be resolved. Further, even when retrying, the no-feed error is not resolved, and when the no-feed JAM is selected, the entire apparatus is stopped, and the user's business efficiency is lowered.

 The present invention has been made in view of the above-described circumstances, and increases the possibility of eliminating the no-feed error due to the feed retry when the no-feed error occurs, thereby reducing the wasted apparatus stop time due to the no-feed JAM. The purpose is to reduce.

 In order to solve the above-described problem, in the present invention, as a first solving means related to an image forming apparatus, a paper placement plate for placing paper, a lifting mechanism for raising and lowering the paper placement plate, A paper feed roller disposed at a position that contacts the uppermost surface of the paper placed on the paper placement plate when the paper placement plate is raised, and a paper feed roller disposed on the downstream side of the paper feed roller to check for the presence or absence of paper. A paper feed sensor to detect, and at the time of paper feed, the paper feed roller is rotated in a state where the uppermost surface of the paper placed on the paper placement plate is in contact with the paper feed roller, and the paper feed sensor An image forming apparatus comprising: a control unit that determines whether or not a no-feed error has occurred based on the output signal, wherein the control unit determines that the no-feed error has occurred; As the paper retry process, the paper is controlled by controlling the lifting mechanism. After raising again once it lowers the plate, characterized in that rotating the paper feed roller again.

 According to the present invention, as the second solving means related to the image forming apparatus, in the first solving means, the control unit does not solve the no-feed error even if the feeding retry process is performed a specified number of times. In this case, it is determined whether or not there is another paper placement plate on which the paper of the same condition is placed. If it is judged that there is, the paper feed roller corresponding to the other paper placement plate is rotated to feed paper. It is characterized by continuing.

  According to the present invention, as a third solving means relating to the image forming apparatus, in the second solving means, the control unit has no other paper placing plate on which the paper of the same condition is placed. If it is determined, the error is stopped and the occurrence of no paper feed JAM is notified to the user.

 According to the present invention, when a no-feed error occurs, as a paper feed retry process, after the paper placement plate is lowered and then raised again by controlling the lifting mechanism, that is, the paper on the paper placement plate Since the paper feed roller is rotated again after trying to change the stacking state of the paper, the possibility of eliminating the no paper feed error due to the paper feed retry is increased, thereby avoiding a wasteful apparatus stop state due to the no paper feed JAM. be able to.

1 is a schematic configuration diagram of a multifunction peripheral A according to an embodiment of the present invention. 2 is a schematic configuration diagram of a sheet feeding cassette 44 of the multifunction peripheral A. FIG. 6 is a flowchart illustrating a control procedure of a paper feeding operation by a control unit 6.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Hereinafter, as an image forming apparatus according to the present invention, a multi-function machine having functions such as a copier, a printer, a scanner, and a facsimile will be described as an example.
FIG. 1 is a schematic configuration diagram of a multifunction peripheral A according to the present embodiment. As shown in FIG. 1, the MFP A includes an operation display unit 1, an image reading unit 2, an image data storage unit 3, a paper transport image forming unit 4, a communication unit 5, and a control unit 6.

   The operation display unit 1 includes operation keys and a touch panel, and functions as a man-machine interface that associates the user with the multifunction peripheral A. The operation display unit 1 outputs an operation instruction of a pressed operation key or an operation button displayed on the touch panel to the control unit 6 and displays various screens on the touch panel based on a control signal input from the control unit 6. indicate.

   Under the control of the control unit 6, the image reading unit 2 reads a surface image (original image) of a document automatically fed by an ADF (Auto document feeder) or a document placed on a platen glass with a line sensor. The document image data is converted into document image data, and the document image data is output to the control unit 6. The image reading unit 2 outputs the document image data to the control unit 6, while the control unit 6 stores the document image data in the image data storage unit 3.

   The image data storage unit 3 is a semiconductor memory, a hard disk device, or the like. Document image data based on a control signal input from the control unit 6 or a print image received by the communication unit 5 from an external client computer (not shown). Data and facsimile image data received from the facsimile apparatus by the communication unit 5 are stored.

   Under the control of the control unit 6, the sheet transport image forming unit 4 transports sheets one by one from the sheet bundle stored in the sheet feeding cassette 44, and puts them on the sheet based on the image data in the image data storage unit 3. An image is formed. As shown in FIG. 1, the sheet transport image forming unit 4 has an image forming unit 41 that forms an image (hereinafter referred to as a toner image) made of toner corresponding to four colors of black, yellow, cyan, and magenta. , Intermediate transfer belt 42, primary transfer roller 43, paper feed cassette 44, paper feed roller 45, paper feed sensor 46, transport roller 47, registration roller 48, secondary transfer roller 49, fixing roller 50, paper discharge roller 51 and The paper discharge tray 52 is configured.

   Each image forming unit 41 forms a toner image corresponding to each color of yellow, magenta, cyan, and black. Four image forming units 41 are provided corresponding to each color at predetermined intervals in the horizontal direction when viewed from the front of the multi-function peripheral A. It has been. As shown in FIG. 1, the image forming unit 41 includes a photosensitive drum 41a on which a toner image is formed on the peripheral surface.

   The intermediate transfer belt 42 is an endless belt provided so as to be in contact with each photoconductive drum 41a, and a toner image formed on the peripheral surface of each photoconductive drum 41a is primarily transferred from each photoconductive drum 41a. It is. The primary transfer roller 43 is disposed so as to face each of the photoconductive drums 41a so as to sandwich the intermediate transfer belt 42. The primary transfer roller 43 is rotated from the photoconductive drum 41a by applying a primary transfer voltage to the intermediate transfer belt 42 while rotating. A roller that primarily transfers the toner image to the intermediate transfer belt 42.

    The paper feed cassette 44 is a container for storing paper P of a predetermined size such as A4 size or B5 size in a bundle shape, and has an opening for exposing at least the uppermost surface of the paper P stacked in a bundle shape. ing. As shown in FIG. 2, the paper feed cassette 44 includes a lift plate 441, a lift plate support 442, a lift motor 443, and a paper guide plate 445.

    The lift plate 441 is a sheet placement plate for placing the sheets P stacked in a bundle shape, and the uppermost surface of the sheets P stacked in a bundle form on the sheet feed roller 45 by the power of the lift motor 443. Raised to abut. The lift plate support 442 supports the lift plate 441 from the lower surface side, is connected to the lift motor 443, and lifts the lift plate 441 by driving the lift motor 443.

    The lift motor 443 is, for example, a DC brush motor, and under the control of the control unit 6, the lift plate 441 is lifted by driving the lift plate support unit 442 by power, and the uppermost surface of the sheets P stacked in a bundle shape Is brought into contact with the paper feed roller 45. Note that the lift plate 441 can be lowered by rotating the lift motor 443 in the reverse direction. As described above, the lift plate support portion 442 and the lift motor 443 serve as a lifting mechanism that lifts and lowers the lift plate 441.

  The paper guide plate 445 is a guide plate provided in each of the width direction and the length direction of the paper P, and is mounted on the lift plate 441 so as to be movable according to the paper size of the paper P. The control unit 6 can detect the paper size of the paper P based on the position of the paper guide plate 445.

Returning to FIG. 1, when the lift plate 441 is lifted, the paper feed roller 45 is disposed at a position where it abuts on the top surface of the paper P stacked in a bundle on the lift plate 441. A roller that feeds the paper P from the paper feed cassette 44 to the paper transport path L one by one by rotating in the paper feed direction while being pressed against the paper. Here, the paper feed direction refers to the direction in which the paper P is transported along the paper transport path L.
A rotation drive mechanism (such as a motor or a reduction gear) (not shown) is connected to the rotation shaft of the sheet feed roller 45, and the sheet feed roller 45 is rotated (start timing, stop timing, rotation, etc.). The speed and the like are controlled by the control of the rotation drive mechanism (particularly motor control) by the control unit 6.

 The paper feed sensor 46 is arranged on the downstream side of the paper feed roller 45 on the paper transport path L (downstream in the paper feed direction), detects the presence or absence of the paper P on the downstream side of the paper feed roller 45, and A signal corresponding to the detection result is output to the control unit 6. For example, the paper feed sensor 46 outputs an on signal (high level signal) when the paper P is present on the downstream side of the paper feed roller 45, and an off signal (low level signal) when the paper P is not present. ) Is output.

The transport roller 47 is arranged on the downstream side of the paper feed roller 45 and the paper feed sensor 46 on the paper transport path L, and is sent out to the paper transport path L by the paper feed roller 45 by rotating in the paper feed direction. The sheet P is conveyed downstream of the sheet conveyance path L.
A rotation drive mechanism (such as a motor or a reduction gear) (not shown) is connected to the rotation shaft of the conveyance roller 47, and the rotation operation (rotation start timing, stop timing, rotation speed, etc.) of the conveyance roller 47 is performed. ) Is controlled by the control of the rotation drive mechanism (particularly motor control) by the controller 6. A configuration in which the rotational force of the paper feed roller 45 is transmitted to the rotation shaft of the transport roller 47 by a belt may be employed.

On the downstream side of the transport roller 47 on the paper transport path L, a pair of registration rollers 48 for adjusting the transport timing of the paper P to the secondary transfer roller 49 are arranged. The pair of registration rollers 48 is composed of two rollers that face each other and rotate in the paper feeding direction while being pressed against each other.
Note that a rotation drive mechanism (such as a motor and a reduction gear) (not shown) is connected to the rotation shaft of one roller of the registration roller 48, and the other roller is idled. That is, the rotation operation (rotation start timing, stop timing, rotation speed, etc.) of one roller is controlled by the control of the rotation drive mechanism (particularly motor control) by the control unit 6, and the other roller is driven by one roller. It is like that.

 The secondary transfer roller 49 is a roller that is disposed so as to sandwich the intermediate transfer belt 42 between the opposing transfer rollers and that forms a secondary transfer nip with the intermediate transfer belt 42. The intermediate transfer belt The toner image on 42 is secondarily transferred to the paper P. That is, the secondary transfer roller 49 applies the secondary transfer voltage with the intermediate transfer belt 42 and the paper P sandwiched in the secondary transfer nip, thereby transferring the toner image on the intermediate transfer belt 42 to the paper P. Next transfer.

   The fixing roller 50 includes a heating roller having a heater therein and a pressure roller pressed against the heating roller. The fixing roller 50 sandwiches the paper P on which the toner image is secondarily transferred by the secondary transfer roller 49. Thus, the paper P is heated and pressed to fix the toner image on the paper P. The paper discharge roller 51 discharges the paper P conveyed from the fixing roller 50 to the paper discharge tray 52. The paper discharge tray 52 is a tray that stores the paper P discharged by the paper discharge roller 51.

 Although not shown in FIG. 1, the paper transport image forming unit 4 includes a plurality of paper feed cassettes 44. Accordingly, a plurality of paper feed rollers 45, paper feed sensors 46, transport rollers 47, and registration rollers 48 are also provided for each paper feed cassette 44.

   The communication unit 5 communicates with an external multifunction peripheral or facsimile apparatus via a telephone line based on a control signal input from the control unit 6, or with a client computer via a local area network. That is, the communication unit 5 has a communication function compliant with a LAN standard such as Ethernet (registered trademark) and a communication function compliant with a facsimile standard such as G3. The communication unit 5 performs e-mail transmission or facsimile transmission / reception, for example.

   The control unit 6 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and an interface circuit that transmits and receives various signals to and from the above-described units, and is stored in the ROM. The overall operation of the multifunction device A is controlled based on the control program. When feeding paper, the control unit 6 rotates the paper feed roller 45 in a state where the uppermost surface of the paper P stacked on the lift plate 441 is in contact with the paper feed roller 45, and based on the output signal of the paper feed sensor 46. In addition, it has a function of determining whether or not a no-feed error has occurred.

Next, the operation of the multifunction peripheral A configured as described above will be described.
For example, a user who wants to copy a document using the multifunction device A sets the document on the image reading unit 2 and presses the copy start key on the operation display unit 1 to cause the multifunction device A to start a copy operation. . When the copy start key of the operation display unit 1 is pressed by the user, the control unit 6 causes the image reading unit 2 to read the original image and stores the original image data obtained from the image reading unit 2 in the image data storage unit 3. Let

 Then, the control unit 6 controls each image forming unit 41 based on the document image data stored in the image data storage unit 3 to form (develop) each color toner image on the surface of each photoconductive drum 41a. At the same time, the primary transfer voltage is sequentially generated at each primary transfer roller 43 while the intermediate transfer belt 42 is rotated, so that the toner images of the respective colors are sequentially superimposed and transferred onto the intermediate transfer belt 42.

 Further, the control unit 6 controls the paper feeding operation of the paper P in parallel with the control of the primary transfer operation of the toner image as described above. Hereinafter, the control procedure of the paper feeding operation executed by the control unit 6 will be described in detail with reference to the flowchart shown in FIG. The control unit 6 controls the paper feeding operation in units of jobs according to the flowchart of FIG. In the present embodiment, one job is a period from when the copy start key is pressed by the user until all original images are printed on the required number of sheets P and discharged.

 As shown in FIG. 3, the control unit 6 first resets the number of fed sheets C1 to “0” (step S1), and then increments the number of fed sheets C1 (step S2). Subsequently, the control unit 6 resets the paper feed retry count C2 to “0” (step S3), and then rotates the paper feed roller 45 for a predetermined time (step S4). Here, as the lift plate 441 rises, the uppermost surface of the paper P stacked on the lift plate 441 and the paper feed roller 45 are in contact with each other. A sheet of paper P is sent out to the paper transport path L.

 Subsequently, the control unit 6 determines whether or not a no-feed error has occurred based on the output signal of the paper feed sensor 46 (step S5). If “Yes”, the process of step S6 described later is performed. On the other hand, in the case of “No”, the process proceeds to step S12 described later. Specifically, in step S <b> 5, when the ON signal is not output from the paper feed sensor 46 even after a predetermined time has elapsed after the paper feed roller 45 is rotated, the control unit 6 generates a no paper feed error. Judge.

 If “Yes” in step S5, that is, if it is determined that a no-feed error has occurred, the control unit 6 determines whether or not the number of sheet feeding retries C2 exceeds the specified number N (step S6). In the case of “Yes”, the process proceeds to a process in step S9 described later, whereas in the case of “No”, the process proceeds to a process in step S7 described later.

 If “No” in step S6, that is, if the paper feed retry count C2 does not exceed the specified count N, the control unit 6 controls the lift motor 443 to lower the lift plate 441 once (lift down). Then, it is raised (lifted up) again (step S7). Then, after the end of step S7, the control unit 6 counts up the number of paper feed retries C2 (step S8), returns to the process of step S4, and rotates the paper feed roller 45 again.

 By the processes in steps S4 to S8, until the no-feed error is resolved (until “No” is determined in step S5), or until the feed retry count C2 exceeds the specified count N (in step S6). The paper feed retry process is repeated until “Yes” is determined.

 In this way, from the state where the lift plate 441 is raised to the best position (the upper limit position of the lift plate 441), the lift plate 441 is once lowered to cause the paper P to be bundled into the position where the paper is being fed. The state is improved, and it is changed to a state in which no paper feeding error occurs as much as possible. Thereby, it is possible to increase the possibility of eliminating the no-feed error due to the feed retry (re-rotation of the feed roller 45).

 If “Yes” in step S6, that is, if the number of paper feed retries C2 exceeds the specified number N (the lift plate 441 is repeatedly lifted down and up, the no paper feed error cannot be resolved). In addition to the currently selected paper feed cassette 44, another paper feed cassette 44 (hereinafter referred to as this paper feed cassette 44) on which the paper P having the same conditions (paper size, paper weight, etc.) is placed is substituted. It is determined whether or not there is a paper feed cassette 44 (step S9).

 If “Yes” in step S9, that is, if there is an alternative paper feed cassette 44 on which the paper P of the same condition is placed, the control unit 6 changes the paper feed from this alternative paper feed cassette 44. (Step S10), the operation display unit 1 is controlled to display a warning screen for notifying the user of the occurrence of no paper feed JAM (Step S11).

 Then, after executing step S11, the controller 6 determines whether or not the number of fed sheets C1 is equal to the required number of fed sheets M in the current job, that is, the feeding of the necessary number of sheets P in the current job is completed. In the case of “No”, the process returns to the process of step S2, while in the case of “Yes”, the control of the paper feeding operation is ended.

 Further, if “No” in step S9, that is, if there is no alternative paper feed cassette 44 on which the paper P of the same condition is placed, the control unit 6 stops as an error with no paper feed JAM, and the operation display part. 1 is displayed to display a warning screen for notifying the user of the occurrence of no-paper-feed JAM (step S13).

 As described above, according to the present embodiment, when a no-feed error occurs, as a paper feed retry process, the lift plate 441 is once lowered and then raised again, that is, the paper P on the lift plate 441 Since the paper feed roller 45 is rotated again after trying to change the stacking state of the paper, the possibility of eliminating the no paper feed error due to the paper feed retry is increased. Can be reduced.

 Also, if the no-feed error cannot be resolved even if the lift plate 441 is lifted up and down repeatedly, the presence or absence of the alternative paper cassette 44 is determined. By continuing the paper feeding operation using the paper cassette 44, it is possible to further reduce the wasteful apparatus stop time due to the occurrence of no paper feeding JAM.

 Here, while using the alternative paper feed cassette 44, a warning screen for notifying the user of the occurrence of no paper feed JAM is displayed. However, since the operation of the entire apparatus is not stopped, the multifunction device continues. A can be used. In addition, by displaying a warning screen indicating that no paper feed JAM has occurred, it is possible to prompt the user to perform a procedure such as insertion / removal of the paper feed cassette 44, and the usability of the multifunction device A is improved.

In addition, this invention is not limited to the said embodiment, The following modifications are mentioned.
For example, in the above-described embodiment, the case where the lift plate 441 is lifted down and lifted up only once during one paper feed retry is illustrated, but one paper feed is performed as the paper feed retry count C2 increases. The number of lift-downs and lift-ups of the lift plate 441 performed during the retry may be increased.
In addition, when no paper feed JAM occurs (when it is determined “Yes” in step S6), it is determined whether the alternative paper feed cassette 44 is present and the paper feed operation is continued, or whether an error is immediately stopped. Switching may be made by manual operation by the user.
Further, in the above-described embodiment, the image forming apparatus including the paper feeding device has been described with reference to the multifunction peripheral A. However, the paper feeding device may be another image forming device such as a copier, a printer, a scanner, or a facsimile machine. Can be applied to.

 A ... multifunction device, 1 ... operation display unit, 2 ... image reading unit, 3 ... image data storage unit, 4 ... paper transport image forming unit, 5 ... communication unit, 6 ... control unit, 41 ... image forming unit, 42 ... Intermediate transfer belt, 43 ... primary transfer roller, 44 ... paper feed cassette, 45 ... paper feed roller, 46 ... paper feed sensor, 47 ... transport roller, 48 ... registration roller, 49 ... secondary transfer roller, 50 ... fixing roller , 51 ... paper discharge roller, 52 ... paper discharge tray, P ... paper

Claims (3)

A paper placement plate for placing paper;
An elevating mechanism for elevating and lowering the paper placing plate;
A paper feed roller disposed at a position in contact with the uppermost surface of the paper placed on the paper placement plate when the paper placement plate is raised;
A paper feed sensor disposed downstream of the paper feed roller to detect the presence or absence of paper;
During paper feeding, the paper feed roller is rotated with the top surface of the paper placed on the paper placement plate in contact with the paper feed roller, and no feed is performed based on the output signal of the paper feed sensor. A control unit that determines whether a paper error has occurred;
An image forming apparatus comprising:
When the control unit determines that the no-feed error has occurred, as a paper feed retry process, the control unit controls the lifting mechanism to lower the paper placing plate once and then raise it again, and then feeds the paper. An image forming apparatus, wherein the roller is rotated again.   If the no-feed error is not resolved even after the paper feeding retry process is performed a specified number of times, the control unit judges whether there is another paper placing plate on which the paper of the same condition is placed, and determines that it exists 2. The image forming apparatus according to claim 1, wherein in this case, the sheet feeding roller corresponding to the other sheet placing plate is rotated to continue feeding.   The control unit, when determining that there is no other paper placement plate on which the paper of the same condition is placed, stops the error and notifies the user of occurrence of no paper feed JAM. Item 3. The image forming apparatus according to Item 2.

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