JP2014030087A - Image formation apparatus - Google Patents

Abstract

An image forming apparatus capable of setting a feeding speed according to the type of document when retrying a feeding operation.
A document size detection unit (document width detection sensor and document length detection sensor) that detects a document size of a document MS placed on a document placement unit, and a document feed unit 3 feeds the document MS. When a failure in feeding the document MS is detected by the document feeding detecting means (document feeding sensor) for detecting the failure and the document feeding detecting means (document feeding sensor), the feeding speed is reduced to reduce the document MS. A feeding control unit (control unit) for retrying feeding of the document, and the feeding control unit (control unit) detects the document detected by the document size detection unit (document width detection sensor and document length detection sensor). Based on the size and the number of retries, the feeding speed at the time of retry is set.
[Selection] Figure 6

Description

  The present invention relates to an image forming apparatus including a document feeding unit that feeds documents one by one and a document reading unit that reads a document fed by the document feeding unit.

  2. Description of the Related Art Conventionally, in a document feeding unit that feeds documents one by one, when document feeding fails, a technology that allows a document feeding operation to be continued by slowing the feeding speed at the time of retry. Has been proposed (see, for example, Patent Document 1).

JP 2004-269256 A

  However, in the conventional technology, when the feeding operation is retried, the feeding speed is uniformly reduced regardless of the type of document. Therefore, a document that is easy to be fed may be unnecessarily slow in feeding speed. In addition, a document that is difficult to feed may fail to feed even during a retry, resulting in a feeding error or an increased number of retries, and the document may be damaged.

  An object of the present invention is made in view of such a point, and an object of the present invention is to provide an image forming apparatus capable of setting a feeding speed according to the type of document when retrying a feeding operation. It is to provide.

An image forming apparatus according to the present invention includes a document feeding unit that feeds documents placed on a document placing unit one by one, and a document reading unit that reads the document fed by the document feeding unit. An image forming apparatus comprising: a document size detecting unit that detects a document size of the document placed on the document placing unit; and a document feeding detection that detects a failure in feeding the document by the document feeding unit. And a feeding control means for slowing down the feeding speed and retrying feeding of the document when the document feeding detecting unit detects a failure in feeding the document. The means is characterized in that the feeding speed at the time of retry is set based on the document size detected by the document size detection means and the number of retries.
Furthermore, in the image forming apparatus of the present invention, the feeding speed at the time of retry is set to be slower as the number of retries is increased.
Furthermore, in the image forming apparatus of the present invention, the feeding speed at the time of retry is set to be slower as the document size is larger.

  According to the present invention, when the feeding operation is retried, the feeding speed according to the document size and the number of retries can be set, so that the probability that the feeding operation is successful with the minimum number of retries increases. As a result, there is an effect that the original is hardly damaged.

1 is a schematic side sectional view showing an internal configuration of a copying machine which is an embodiment of an image forming apparatus according to the present invention. FIG. 2 is a schematic side sectional view showing an internal configuration of a document feeding unit shown in FIG. FIG. 3 is a top view illustrating a configuration of a document placement unit illustrated in FIG. 2. FIG. 2 is a block diagram illustrating a schematic configuration of the copier illustrated in FIG. 1. FIG. 6 is a diagram illustrating an example of a retry feeding speed setting table for setting a feeding speed at the time of retry in the feeding operation by the document feeding unit illustrated in FIG. 1. 3 is a flowchart for explaining a feeding operation by a document feeding unit shown in FIG. 1.

Next, embodiments of the present invention will be specifically described with reference to the drawings.
The image forming apparatus according to the present embodiment is a copying machine 1, and includes a document reading unit 2, a document feeding unit 3, a main body unit 5, and an operation unit 6, as shown in FIG. The document reading unit 2 is disposed on the upper portion of the main body unit 5, and a recording paper discharge tray 51 is formed between the document reading unit 2 and the main body unit 5. The document feeding unit 3 is disposed on the upper part of the document reading unit 2. Further, the document feeding unit 3 is configured to be retractable, and is configured such that the upper surface of the document reading unit 2 can be opened by opening the document feeding unit 3 upward. The operation unit 6 is disposed on the front side of the image forming apparatus 1. Although the image forming apparatus according to the present embodiment has been described with reference to the copying machine 1, it is needless to say that a scanner, a multifunction machine, and the like are included.

  The operation unit 6 is provided with a liquid crystal display unit 61 and operation buttons 62. The user operates the operation unit 6 to input instructions, thereby making various settings of the copying machine 1 and executing various functions such as image formation. The liquid crystal display unit 61 displays the status of the copier 1, displays the image formation status and the number of copies, and can be used as a touch panel for various settings such as functions such as double-sided printing and black-and-white reversal, magnification setting, and density setting. It has become. As the operation buttons 62, a start button for instructing the user to start image formation, a stop / clear button used for stopping image formation, and the like, and various settings of the copying machine 1 are used for default settings. A reset button, a numeric keypad, and the like are provided.

  The document reading unit 2 includes a scanner 21, a platen glass 22, and a document reading slit 23. The scanner 21 includes an exposure lamp, a CCD (Charge Coupled Device) sensor, and the like, and is configured to be movable in the document feeding direction by the document feeding unit 3. The platen glass 22 is an original table made of a transparent member such as glass. The document reading slit 23 has a slit formed in a direction orthogonal to the feeding direction of the document MS by the document feeding unit 3.

  When reading the document MS placed on the platen glass 22, the scanner 21 is moved to a position facing the platen glass 22 and reads the document MS while scanning the document placed on the platen glass 22. Data is acquired, and the acquired image data is output to the main unit 5. When reading the document MS fed by the document feeding unit 3, the scanner 21 is moved to a position facing the document reading slit 23, and the document by the document feeding unit 3 is moved through the document reading slit 23. In synchronization with the MS feeding operation, the document MS is read to acquire image data, and the acquired image data is output to the main unit 5.

  The document feeding unit 3 is an ADF (Auto Document Feeder), and includes a document placing unit 31, a document discharge tray 32, a document feeding mechanism 33, and a document guide 34. The original MS placed on the original placement portion 31 by center alignment by the original guide 34 is sequentially fed out one by one by the original feeding mechanism 33 and fed to a position facing the original reading slit 23, and thereafter. The document is discharged to the document discharge tray 32.

  As shown in FIG. 2, the document feeding mechanism 33 includes a pickup roller 35, a document feeding roller 36, a registration roller 37, a document feeding sensor 38, a document pressing unit 39, and a document discharge roller 40. Each roller is rotationally driven by a stepping motor (not shown).

  The original MS set on the original placement unit 31 with the image surface facing upward is first sent to the transport roller 35 by the pickup roller 35 as a primary feeding operation. The document MS sent to the transport roller 35 is transported toward the registration roller 37. A document feed sensor 38 is disposed on the front side of the registration roller 37 in the document conveyance direction. The transport roller 35 and the pickup roller 35 transport the document MS for a predetermined distance after the leading edge of the document MS is detected by the document feed sensor 38, and then the rotation drive is stopped and the primary feeding operation is finished. The At the end of the primary feeding operation, the leading edge of the document MS is in contact with the nip portion of the registration roller 37. As the document feeding sensor 38, for example, an optical sensor that irradiates light toward the conveyed document MS and receives reflected light thereof can be used. The document feeding sensor 38 functions as a document feeding detecting unit that detects a feeding failure due to the primary feeding operation. That is, when the leading edge of the document MS is not detected within a predetermined time by the document feeding sensor 38 after the start of the primary feeding operation, a feeding failure due to the primary feeding operation is detected, and the primary feeding operation is performed. It will be retried.

  After the completion of the primary feeding operation, the secondary feeding operation is started at a predetermined timing. As the secondary feeding operation, the conveyance of the document MS by the registration roller 37 and the document discharge roller 40 is started. After the document MS passes between the document pressing unit 39 and the document reading slit 23 of the document reading unit 2, The document is discharged to the document discharge tray 32. Thereafter, the primary feeding operation and the secondary feeding operation are repeated until there is no document MS set on the document placement unit 31.

  Referring to FIG. 3, the document placing portion 31 is urged upward by a biasing means such as a spring (not shown), and the document MS set on the document placing portion 31 is pressed against the pickup roller 35 with a predetermined pressure. A set document pressing member 41, a document detection sensor 42 that detects the presence or absence of the document MS placed on the document placement unit 31, a document width detection sensor 43, and a document length detection sensor 44. .

  The document detection sensor 42 functions as a document detection unit that detects the document MS placed on the document placement unit 31, and detects the document placement surface of the document placement unit 31 regardless of the document size of the document MS. It is placed in a position where it can

  The document width detection sensor 43 and the document length detection sensor 44 function as document size detection means for detecting the document size of the document MS placed on the document placement unit 31 by the document guide 34 so as to be centered. The document width detection sensor 43 is disposed at a position 105 mm from the center line C in the width direction on the document placement surface of the document placement unit 31. Accordingly, the document width detection sensor 43 detects whether the document width of the document MS placed on the document placement unit 31 by center alignment by the document guide 34 is equal to or greater than 210 mm which is the A4 document width. The document length detection sensor 44 is disposed on the document placement surface of the document placement unit 31 at a position of 297 mm in the length direction from the front end position of the document MS placed on the document placement unit 31. Accordingly, the original length detection sensor 44 detects whether the original length of the original MS placed on the original placement portion 31 is 297 mm or more, which is the A4 original length.

  The document detection sensor 42, the document width detection sensor 43, and the document length detection sensor 44, for example, emit light toward the document MS placed on the document placement unit 31 and receive the reflected light. An optical sensor or a mechanical switch that contacts the document MS placed on the document placement unit 31 can be used.

  When a copy operation (reading of the document MS) is instructed by the operation button 62 of the operation unit 6 in a state where the document MS is not detected by the document detection sensor 42, the document reading unit 2 reads the document placed on the platen glass 22. The flat reading mode for reading the MS is entered, and the document MS placed on the platen glass 22 is read. In the flat reading mode, the document reading unit 2 acquires the image data line by line while moving the scanner 21 to a position facing the platen glass 22 and moving the scanner 21 in the sub-scanning direction orthogonal to the main scanning direction. The processed image data is output to the main unit 5.

  When a copy operation (reading of the document MS) is instructed by the operation button 62 of the operation unit 6 in a state where the document MS is detected by the document detection sensor 42, the document feeding unit 3 sequentially reads the document MS one by one. The document is fed to a position facing the document reading slit 23 and the document reading unit 2 enters an ADF reading mode in which the document fed by the document feeding unit 3 is read at the position of the MS document reading slit 23. In the ADF reading mode, the document reading unit 2 moves the scanner 21 to a position facing the document reading slit 23, and the document feeding unit 3 feeds the document MS through the document reading slit 23 (secondary feeding operation). The image data is acquired by reading the document MS in synchronism with), and the acquired image data is output to the main unit 5.

  The main body 5 includes the recording unit 7, and includes a paper feeding unit 52, a recording paper conveyance path 53, a recording paper conveyance roller 54, and a recording paper discharge roller 55. The paper feed unit 52 includes a plurality of paper feed cassettes 52a1 to 52an and recording paper feed rollers 52b1 to 52bn for feeding recording paper from the paper feed cassettes 52a1 to 52an one by one to the recording paper transport path 53. The recording paper feed rollers 52b1 to 52bn, the recording paper transport roller 54, and the recording paper discharge roller 55 function as a recording paper transport unit, and the recording paper is transported. The recording paper fed to the recording paper transport path 53 by the recording paper feed rollers 52 b 1 to 52 bn is transported to the recording unit 7 by the recording paper transport roller 54. Then, the recording paper on which recording has been performed by the recording unit 7 is discharged to the recording paper discharge tray 51 by the recording paper discharge roller 55.

  The recording unit 7 includes a photosensitive drum 71, an exposure unit 72, an image forming unit 73, a transfer unit 74, and a fixing unit 75. The exposure unit 72 is an optical unit including a laser device, a mirror, and the like, and outputs a laser beam based on image data to expose the photosensitive drum 71 to form an electrostatic latent image on the surface of the photosensitive drum 71. To do. The image forming unit 73 is a developing unit that develops the electrostatic latent image formed on the photosensitive drum 71 using toner, and forms a toner image based on the electrostatic latent image on the photosensitive drum 71. The transfer unit 74 transfers the toner image formed on the photosensitive drum 71 by the image forming unit 73 to a recording sheet. The fixing unit 75 heats the recording paper on which the toner image is transferred by the transfer unit 74 to fix the toner image on the recording paper.

  FIG. 4 is a block diagram showing a schematic configuration of the copying machine 1. The document reading unit 2, document feeding unit 3, transport unit (recording paper feed rollers 52 b 1 to 52 bn, recording paper transport roller 54, recording paper discharge roller 55), the operation unit 6 and the recording unit 7 are the control unit 8. And the operation is controlled by the control unit 8. In addition, an image processing unit 9 and a storage unit 10 are connected to the control unit 8.

  The control unit 8 is an information processing unit such as a microcomputer including a ROM (Read Only Memory), a RAM (Random Access Memory), and the like. The ROM stores a control program for controlling the operation of the copying machine 1. The control unit 8 reads out a control program stored in the ROM and develops the control program in the RAM, thereby controlling the entire apparatus according to predetermined instruction information input from the operation unit 6.

  The image processing unit 9 is means for performing predetermined image processing on the image data. For example, image improvement processing such as enlargement / reduction processing, gradation adjustment, and density adjustment is performed.

  The storage unit 10 is a storage unit such as a semiconductor memory or an HDD (Hard Disk Drive). The storage unit 10 stores image data acquired by reading the document MS by the document reading unit 2, and stores various management information. ing. Further, a retry feeding speed setting table for setting a feeding speed when the feeding failure due to the primary feeding operation is detected and the primary feeding operation is retried is stored. As shown in FIG. 5, the retry feeding speed setting table sets the feeding speed (ratio to the feeding speed before retrying) according to the number of retries and the size of the original MS (original width, original length). Has been. In the retry feeding speed setting table, the feeding speed is set to become slower as the number of retries increases, and is set to become slower as the document size increases even with the same number of retries.

Next, the feeding operation in the copying machine 1 of the present embodiment will be described in detail with reference to FIG.
The control unit 8 monitors the pressing of the start button by the operator in various modes with a scanning operation (step A1). When the start button is pressed, the control unit 8 determines the presence or absence of the document MS placed on the document placement unit 31 based on the output of the document detection sensor 42 (step A2). If is not detected, the process is terminated without performing the feeding operation.

  When the document MS is detected by the document detection sensor 42 in step A2, the control unit 8 sets the variable n to zero (step A3), and the document width detection sensor 43 and the document length detection sensor 44 The document size of the document MS placed on the document placement unit 31 is detected (step A4).

  Next, the control unit 8 starts the feeding operation (primary feeding operation, secondary feeding operation) by the document feeding unit 3 (step A5). Was the feeding by the primary feeding operation succeeded? It is determined whether or not (step A6). When the leading edge of the document MS is detected within a predetermined time by the document feeding sensor 38 after the start of the primary feeding operation, the control unit 8 determines that feeding by the primary feeding operation has been successful. After completion of the secondary feeding operation, it is determined whether or not there is a document MS placed on the document placement portion 31 (step A7). When the document MS is detected by the document detection sensor 42 in step A7, the control unit 8 returns to step A5 and starts the feeding operation of the next document MS. On the other hand, if the document MS is not detected by the document detection sensor 42 in step A7, the control unit 8 determines that all the documents MS placed on the document placement unit 31 have been fed and ends the process. .

  If the leading edge of the document MS is not detected within a predetermined time by the document feeding sensor 38 after the start of the primary feeding operation, the control unit 8 determines that feeding by the primary feeding operation has failed in step A6. After determining and incrementing the variable n (step A8), it is determined whether or not the variable n has reached a preset set value N (step A9).

  If the variable n has not reached the preset setting value N in step A9, the control unit 8 stores the number of retries n, the document size detected in step A4, and the storage unit 10. After the feeding speed is set based on the retry feeding speed setting table (step A10), the process returns to step A5 to retry the feeding operation of the document MS at the feeding speed set in step A10. The feeding speed set in step A10 is set to be slower than the feeding speed of the feeding operation performed in the immediately preceding step A5. In the retry feeding speed setting table, the feeding speed is set so as to be slower as the number of retries is increased, and is set so as to be slower as the document size is increased even with the same number of retries. Yes. Therefore, the probability that the feeding operation will be successful with the minimum number of retries increases, and as a result, the original MS is less likely to be damaged.

  In step A9, when the variable n reaches a preset set value N, the control unit 8 displays a message notifying the feeding error on the liquid crystal display unit 61 of the operation unit 6, and the feeding error is indicated by the user. (Step A11), and the process is terminated. In the present embodiment, as shown in FIG. 5, the feeding speed up to four times of retry is set by the retry feeding speed setting table. Accordingly, the set value N to be compared with the variable n in step A9 is set to “5”.

  As described above, according to the present embodiment, the document size detecting means (the document width detecting sensor 43 and the document length detecting sensor 44) for detecting the document size of the document MS placed on the document placing unit 31; The document feeding detection unit (document feeding sensor 38) that detects a failure in feeding the document MS by the document feeding unit 3 and the document feeding detection unit (document feeding sensor 38) cause a failure in feeding the document MS. When detected, it comprises a feeding control means (control section 8) for slowing the feeding speed and retrying the feeding of the document MS, and the feeding control means (control section 8) is a document size detecting means (control section 8). Based on the document size and the number of retries detected by the document width detection sensor 43 and the document length detection sensor 44), the feeding speed at the time of retry is set. Also, the feeding speed at the time of retry is set to be slower as the number of retries is larger and slower as the document size is larger. With this configuration, when the feeding operation is retried, the feeding speed can be set according to the document size and the number of retries, so the probability that the feeding operation will succeed with the minimum number of retries increases. This has the effect of making it difficult to hurt the manuscript.

  Note that the present invention is not limited to the above-described embodiments, and it is obvious that the embodiments can be appropriately changed within the scope of the technical idea of the present invention. In addition, the number, position, shape, and the like of the constituent members are not limited to the above-described embodiment, and can be set to a suitable number, position, shape, and the like in practicing the present invention. In each figure, the same numerals are given to the same component.

DESCRIPTION OF SYMBOLS 1 Copier 2 Original reading part 3 Original feeding part 5 Main body part 6 Operation part 7 Recording part 8 Control part 9 Image processing part 10 Storage part 21 Scanner 22 Platen glass 23 Original reading slit 31 Original placement part 32 Original discharge tray 33 Document feeding mechanism 34 Document guide 35 Pickup roller 36 Document feeding roller 37 Registration roller 38 Document feeding sensor 39 Document pressing unit 40 Document discharge roller 41 Set document pressing member 42 Document detection sensor 43 Document width detection sensor 44 Document length detection Sensor 51 Recording paper discharge tray 52 Paper feed section 52a1 to 52an Paper feed cassette 52b1 to 52bn Recording paper feed roller 53 Recording paper transport path 54 Recording paper transport roller 55 Recording paper discharge roller 61 Liquid crystal display section 62 Operation button 71 Photosensitive drum 72 Exposure part 73 Image forming section 74 Transfer section 75 Fixing section

Claims (3)

An image forming apparatus comprising: a document feeding unit that feeds documents placed on a document placing unit one by one; and a document reading unit that reads the document fed by the document feeding unit.
Document size detection means for detecting the document size of the document placed on the document placement unit;
A document feeding detection means for detecting a failure in feeding the document by the document feeding unit;
A feeding control means for slowing down the feeding speed and retrying feeding of the original when the original feeding detecting means detects a failure in feeding the original;
The image forming apparatus according to claim 1, wherein the feeding control unit sets the feeding speed at the time of retry based on the document size detected by the document size detecting unit and the number of retries.   The image forming apparatus according to claim 1, wherein the feeding speed at the time of retry is set to be slower as the number of retries increases.   The image forming apparatus according to claim 1, wherein the feeding speed at the time of retry is set to be slower as the document size is larger.

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