JP2011022393A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress an increase in a cost while preventing forgetting of taking out an original and to prevent shift of a set original. <P>SOLUTION: An image reading unit 50 has a pressing plate 52 for pressing the original that is turnably attached to the image reading unit 50 and includes: a torsion coil spring 44 biasing the pressing plate 52 in the opening direction; a hook 43 arranged on the pressing plate 52; a latch 46 to be engaged with the hook 43 when the pressing plate 52 is closed; and a CPU301 for releasing the latch 46 according to the end of reading of the original by the image reading unit 50 or the end of image formation by a printer 53. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a pressure plate unit of an image reading unit of an image forming apparatus, and more particularly to a technique for preventing a document from being forgotten.

  Conventionally, in an image forming apparatus provided with an image reading unit, forgetting to remove a document has been a problem. In many cases of forgetting to remove a document, the user waits in front of the image forming apparatus until the end of copying (hereinafter simply referred to as job end), but when the job ends, the user leaves only with the output paper. In such a case, the user forgets to remove the document and forgets to place the document in the image reading unit.

  From the viewpoint of security enhancement in recent offices and the security aspect when an unspecified number of users use an image forming apparatus in a convenience store or the like, this document misplacement problem is an important issue.

  As countermeasures, various countermeasures have been proposed in consideration of prevention of forgetting to take a manuscript. For example, a configuration has been proposed in which when the image forming apparatus detects the end of a job and then determines that the original has not been removed, the pressure plate is automatically opened by a motor (see, for example, Patent Document 1).

Japanese Patent Application Laid-Open No. 06-035084

  However, in the conventional technology for automatically opening the pressure plate, since a motor is used for the automatic opening configuration, there is a problem that the cost is high. Further, the invention described in Patent Document 1 (Claim 3) includes a document pressure plate, drive means for driving the document pressure plate to open and close, and a sensor for detecting a human body position. Patent Document 1 proposes an image forming apparatus in which a document pressure plate is opened by an opening / closing drive unit every time an image forming operation is completed when a sensor detects a human body at the end of each copy. This prevents you from forgetting to take a manuscript. However, if the user leaves the spot with the discharged paper at the same time as the last sheet of the copy (last paper) is discharged, the human body is not detected and the pressure plate is not opened, resulting in misplacement of the original. End up.

  Further, when making a multi-copy, it is often the case that a trial copy is made first and a multi-copy is made after confirming whether a desired copy image has been obtained. In such a case, the pressure plate is released at the end of the trial copy. However, the set original is displaced due to the influence, and there is a problem that the user needs to reset the original setting position again.

  The present invention has been made under such circumstances, and an object thereof is to suppress an increase in cost while preventing forgetting to take a document, and to prevent a set document from being displaced.

  In order to solve the above problems, the present invention comprises the following arrangement.

  (1) In an image forming apparatus including a reading unit that reads a document and an image forming unit that forms an image on a sheet based on information of the document read by the reading unit, the reading unit rotates to the reading unit A pressure plate portion that is attached to the pressure plate portion and that presses the original, and biases the pressure plate portion in the opening direction; hook means provided on the pressure plate portion; and when the pressure plate portion is closed, An image forming apparatus comprising: latch means engaged with a hook means; and control means for releasing the latch means in response to completion of reading of a document by the reading section or completion of image formation by the image forming section. .

  (2) In an image forming apparatus including a reading unit that reads a document and an image forming unit that forms an image on a sheet based on the information of the document read by the reading unit, the reading unit rotates to the reading unit A first pressure plate that is detachably attached and presses the document; and a second pressure plate that is rotatably attached to the first pressure plate and presses the document. An image forming apparatus comprising: a control unit that controls to open the second pressure plate in response to completion of image formation by the image forming unit.

  According to the present invention, it is possible to suppress an increase in cost while preventing forgetting to remove a document and to prevent a set document from being displaced.

Schematic configuration diagram of image forming apparatuses according to first and second embodiments The figure explaining the automatic open | release structure of the pressure plate part of Example 1. Block diagram of a control system that performs automatic opening control of the first and second embodiments Flowchart explaining the automatic opening control process of the first and second embodiments FIG. 6 is a diagram for explaining an automatic opening configuration of a pressure plate portion and document takeout according to a second embodiment.

  The mode for carrying out the present invention will be described in detail below with reference to examples.

(1) Overall Configuration of Image Forming Apparatus FIG. 1 is a cross-sectional view of the overall configuration of the image forming apparatus of this embodiment, and FIG. 2 is a schematic diagram of a pressure plate unit and an image reading unit of the image forming apparatus. In FIG. 1, when the user opens the platen 52, sets a document and presses the copy button (or start button), the image reading unit 50 reads the document image and transmits the image information to the laser scanner 12 side. Then, the image forming apparatus forms an image on the number of sheets designated by the user by the following process. When the surface of the photosensitive drum 11 uniformly charged by the charging roller 33 is scanned with laser light corresponding to image information from the laser scanner 12, an electrostatic latent image is formed on the surface of the photosensitive drum 11. The electrostatic latent image is developed as a toner image with toner attached thereto by the developing unit 13. The toner image is transferred by the transfer roller 25 onto the sheet conveyed by the registration roller 4 in synchronization with the rotation of the photosensitive drum 11.

  The toner supplied from the toner replenishing device 14 reaches the developing unit 13 and is replenished to the photosensitive drum 11 by reaching the developing sleeve 17 while being stirred inside. The electrostatic latent image is converted into a toner image by the toner. Developed. Note that the toner remaining on the photosensitive drum 11 after the transfer of the toner image to the sheet is removed by the cleaning member 23 in contact with the photosensitive drum 11 and accommodated in a waste toner container (not shown) by the conveying screw 24. The photosensitive drum 11 that has been cleaned is exposed to a pre-exposure unit (not shown) to eliminate uneven charging remaining on the surface, and is uniformly charged by the charging roller 33 in preparation for the next latent image formation. The Reference numeral 20 denotes a detachable photosensitive drum unit, and 22-a and 22-b denote photosensitive drum unit attachment / detachment rails.

  A sheet such as paper is conveyed from the paper feeding device 3 to a transfer nip portion 26 between the photosensitive drum 11 and the transfer roller 25, and a toner image formed on the photosensitive drum 11 is transferred. The sheet on which the toner image has been transferred passes through the fixing nip portion 32 of the fixing unit 19, is heated and pressed by the fixing unit 19 and is fixed on the surface of the sheet, passes through the discharge port 21 and the discharge sensor 51 and passes through the discharge tray. 27 is discharged. In the case of double-sided printing, similarly, the sheet conveyed to the discharge port 21 is reversed (switched back) at the discharge port 21 and conveyed to the double-sided roller 40, and is again fed to the transfer nip portion 26 through the double-sided conveyance path 41. Paper. The re-fed sheet fixes the toner image as in the first side, passes through the discharge port 21 and the discharge sensor 51 and is discharged to the discharge tray 27.

(2) Configuration of Automatic Opening of Pressure Plate Part FIG. 2 is a diagram illustrating an automatic opening mechanism of the pressure plate part 52. 2A is a view from the upper side of the main body showing a state in which the pressure plate portion 52 is closed, FIG. 2B is a view from the left side of the main body, and FIG. FIG. 2D is a partially enlarged view of the torsion coil spring 44 as viewed from above the main body showing the opened state. It is assumed that the user stands on the side where the pressure plate portion 52 is opened with respect to the image forming apparatus (see, for example, FIG. 5B).

  The pressure plate portion 52 has a hook portion 43 for fixing in a closed state. When the pressure plate portion 52 is closed, the pressure plate portion 52 engages with a latch portion 46 provided in the image reading portion 50. As shown in FIG. 2, the pressure plate portion 52 is always biased by the torsion coil spring 44 in the opening direction. Then, by pulling the solenoid 45, the engagement state of the latch portion 46 and the hook portion 43 is released, and the pressure plate portion 52 is released by the biasing force of the spring. The released pressure plate portion 52 is stopped at a certain opening angle by a stopper portion 47 for restricting the opening angle.

(3) Control of automatic opening of pressure plate unit Next, a flow of processing in which the pressure plate unit 52 automatically opens at the end of a job will be described with reference to FIGS. FIG. 3 is a block diagram showing the configuration of a control system that controls the automatic opening of the pressure plate portion 52. The CPU 301 executes control for automatically opening the pressure plate portion 52. The operation unit 300 has a start key 300a, and the copy operation starts when the user presses the start key 300a. Reference numeral 302 denotes a pressure plate opening / closing detection sensor that detects the opening / closing of the pressure plate portion 52. For example, the pressure plate portion 52 transmits an ON signal to the CPU 301 when the pressure plate portion 52 is in an open state and an OFF signal when the pressure plate portion 52 is in a closed state. Reference numeral 303 denotes a jam / error detection sensor that detects a paper jam (hereinafter referred to as jam) or an error occurring during a job. 45 is a solenoid that automatically releases the pressure plate portion 52 by releasing the engagement state between the latch portion 46 and the hook portion 43. The solenoid 45 moves in the direction of the arrow shown in FIG. 2B according to whether the CPU 301 is turned on or off, and the latch unit 46 rotates in the direction of the arrow in accordance with the movement of the solenoid 45, so that the latch unit 46 and the hook unit 43 are engaged. In this case, the release is performed. Reference numeral 305 denotes a discharge paper counter that counts the number of discharged sheets based on the ON / OFF signal of the discharge sensor 51. The CPU 301 refers to the information of the discharge sheet counter 305, and the discharged sheet is the last sheet (the last sheet of the job). Sheet). A display unit 304 of the operation unit 300 displays an alarm message or a message prompting the user to perform jam processing (hereinafter simply referred to as an alarm / jam display), and conveys information to the user.

  FIG. 4 is a flowchart regarding the automatic opening control of the pressure plate unit 52 executed by the CPU 301. When the user presses the start key 300a in step 1 (hereinafter referred to as S1 or the like), in S2, the CPU 301 determines whether or not the pressure plate portion 52 is closed based on the detection result of the pressure plate open / close detection sensor 302. If the CPU 301 determines in S2 that the pressure plate 52 is not closed, the process proceeds to S3. As a situation where the pressure plate portion 52 is not closed, a user may forget to close the pressure plate portion 52 or may copy a thick book original such as a book or a booklet. In S3, the CPU 301 displays a confirmation message on the display unit 304 to call attention to the user. When the user presses a confirmation button (not shown) on the touch panel of the operation unit 300, in S4, the CPU 301 reads a document by the image reading unit 50 and a printing operation by the printer unit 53 which is an image forming unit (hereinafter simply referred to as a job). To start. When the job is started, the CPU 301 refers to the discharged paper counter 305 to monitor whether the sheet to be discharged is the last paper. If the CPU 301 determines that the sheet is the last paper in S5, the job is ended.

  On the other hand, if the CPU 301 determines in S2 that the pressure plate 52 is closed based on the detection result of the pressure plate open / close detection sensor 302, the process proceeds to S6. In step S6, the CPU 301 starts a job. If the CPU 301 detects a jam or error by the jam / error detection sensor 303 before the job is completed in S7 and determines that a jam or error has occurred, the process proceeds to S8. In step S8, the CPU 301 causes the display unit 304 to display an alarm and jam processing display. At this time, the CPU 301 does not open the pressure plate portion 52. When the user removes the cause of the jam or the error by performing the jam processing or the like, the CPU 301 starts the job again, for example, refeeds in S9.

  If the CPU 301 determines in S7 that no jam or error occurs, the process proceeds to S10. In S10, the CPU 301 refers to the discharge paper counter 305, and when the last paper passes through the discharge sensor 51 and is turned on, in S11, the CPU 301 turns on the solenoid 45 of the pressure plate portion 52 and rotates the latch portion 46. As a result, the hook portion 43 is released in S12, and the pressure plate portion 52 is automatically opened by the biasing force of the torsion coil spring 44. As described above, since the pressure plate unit 52 is automatically opened simultaneously with the end of the job, the user is alerted to whether or not he / she has forgotten to take out the original, takes out the original, and takes out the output paper on the discharge tray of the discharge tray 27.

  As described above, according to the present embodiment, the pressure plate that is spring-biased is released by releasing the latch (without using a motor) upon completion of document reading or image formation, thereby preventing forgetting to remove the document. However, the cost increase can be suppressed.

(1) Configuration of automatic opening of pressure plate part FIGS. 5 (a) and 5 (b) are diagrams for explaining an automatic opening mechanism of the pressure plate part 52 of this embodiment, from the left side of the main body showing the state where the pressure plate part 52 is closed. FIG. 2 is a view of the entire image forming apparatus in a state where a pressure plate portion 52 is opened as viewed from the left side of the main body. In FIG. 5, the pressure plate unit 52 is configured in two pieces, the first pressure plate 48 is rotatable with respect to the image reading unit 50, and the second pressure plate 49 is illustrated in FIG. It is the structure which can be rotated in the arrow direction shown. Further, the second pressure plate 49 has a hook portion 43 and engages with a latch portion 46 provided in the image reading portion 50 when the second pressure plate 49 is closed. The second pressure plate 49 is spring-biased by the torsion coil spring 44 in a direction in which it always opens. Then, when the solenoid 45 is pulled, the engagement state of the latch portion 46 and the hook portion 43 is released, and the second pressure plate 49 rotates to the stopper portion 47. The configuration of the torsion coil spring 44 is, for example, as shown in FIG.

  The automatic opening control of the pressure plate 52 is the same as the block diagram of FIG. 3 and the flowchart of FIG. In the present embodiment, only the second pressure plate 49 is automatically opened in S12 of the flowchart of FIG.

  When copying a large number of copies, depending on the user, it is often the case that an output sheet on which a desired image has been transferred is discharged and first checked to make a single copy, and then a multiple copy job is performed again. Even in such a case, the second pressure plate 49 is opened simultaneously with the end of the first copy job that the user has made a trial. However, since the first pressure plate 48 is not opened and only the second pressure plate 49 is automatically opened while the document is held down, there is no possibility of document misalignment, and the user has to copy many copies again. It is only necessary to close the second pressure plate 49.

  As described above, if the user can confirm the output paper and confirm that the desired image is transferred and output, the second pressure plate 49 can be closed and the multi-copy operation can be continuously performed.

(2) Document Extraction A case will be described in which the job ends and the user removes the document. FIG. 5C is a view of the pressure plate portion 52 when the user takes out the original as viewed from the left side of the main body. The second pressure plate 49 is opened with the opening angle maintained at 90 ° or less by the stopper portion 47. The first pressure plate 48 is configured to be manually rotated with respect to the image reading unit 50, and the user manually opens the first pressure plate 48 and takes out the document.

  As described above, in this embodiment, the first pressure plate that is spring-biased is released by releasing the latch (without using a motor) in accordance with the end of document reading or the end of image formation. The second pressure plate is opened while the original plate is pressed. As a result, according to the present embodiment, it is possible to suppress an increase in cost while preventing forgetting to take a document and to prevent a set document from being displaced.

  In the second embodiment, a configuration is shown in which the spring is biased by the torsion coil spring 44 in the direction to open the second pressure plate 49 and the engagement and release of the latch portion 46 and the hook portion 43 are controlled using the solenoid 45. . In this embodiment, the second pressure plate 49 is automatically opened by being driven by a motor (not shown). Therefore, in the control of automatically opening the pressure plate 52 in the present embodiment, in S11 of FIG. 4, the CPU 301 drives a motor (not shown) by a motor drive (not shown) and opens the second pressure plate 49 by the motor in S12. Let Also in the block diagram of the control system of FIG. 3, the solenoid 45 is replaced with a motor drive unit and a motor.

  Thus, even if the second pressure plate 49 is configured to automatically open the second pressure plate 49 by driving the motor, the second pressure plate is opened in a state where the first pressure plate is pressed down while preventing forgetting to remove the document. It is possible to prevent misalignment of the set document.

43 Hook 44 Torsion Coil Spring 46 Latch 52 Pressure Plate 301 CPU

Claims (5)

An image forming apparatus comprising: a reading unit that reads a document; and an image forming unit that forms an image on a sheet based on information on the document read by the reading unit.
The reading unit is rotatably attached to the reading unit, and includes a pressure plate unit that holds the document.
Urging means for urging in the direction of opening the pressure plate part;
Hook means provided on the pressure plate portion;
Latch means for engaging with the hook means when the pressure plate portion is closed;
Control means for releasing the latch means in response to completion of reading of the document by the reading section or completion of image formation by the image forming section;
An image forming apparatus comprising: A solenoid that pulls in a direction to release the latch means;
The image forming apparatus according to claim 1, wherein the control unit controls to pull the solenoid when the latch unit is released. An image forming apparatus comprising: a reading unit that reads a document; and an image forming unit that forms an image on a sheet based on information on the document read by the reading unit.
The reading unit includes a first pressure plate that is rotatably attached to the reading unit and presses the document, and a second pressure plate that is rotatably attached to the first pressure plate and presses the document. ,
Control means for controlling to open the second pressure plate in response to completion of reading of a document by the reading unit or completion of image formation by the image forming unit;
An image forming apparatus comprising: A motor for rotating the second pressure plate in the opening direction;
The image forming apparatus according to claim 3, wherein the control unit controls the motor to be driven in a direction to open the second pressure plate when the second pressure plate is opened. An urging means provided on the first pressure plate for urging the second pressure plate in the opening direction;
Hook means provided on the second pressure plate;
Latch means for engaging the hook means when the second pressure plate is closed,
The image forming apparatus according to claim 3, wherein the control unit releases the latch unit in response to completion of reading of a document by the reading unit or completion of image formation by the image forming unit.

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