Image forming apparatus

Abstract

To provide an image forming apparatus that improves, at low cost, visibility inside the apparatus during maintenance.SOLUTION: A sheet sensor 31 is provided on a conveyance path of a print sheet and optically detects the print sheet. A cover opening and closing sensor 51a detects that an opening and closing cover 51 is opened. In a case where a maintenance mode is selected or a predetermined defect is detected, when the cover opening and closing sensor 51a detects that the opening and closing cover 51 is opened, a controller 61 causes the sheet sensor 31 to light up.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus. [Background technology]

[0002] One image forming apparatus has a working table, an opening formed below the working table, and an openable and closable cover for the opening; furthermore, an illumination means is provided on the underside of the working cover that lights up when the cover is opened to illuminate the area below the working cover (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2012-155069 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the above-mentioned image forming apparatus, although the visibility of the inside of the apparatus is improved by the light emitted from the lighting means, it is necessary to provide a dedicated lighting means, which increases the cost of the apparatus.

[0005] The present invention has been made in consideration of the above problems, and has an object to provide an image forming apparatus which improves visibility of the inside of the apparatus during maintenance at low cost. [Means for solving the problem]

[0006] The image forming apparatus of the present invention comprises a sheet sensor provided in a transport path for a print sheet and optically detecting the print sheet, an opening / closing cover, a cover opening / closing sensor that detects when the opening / closing cover is opened, and a controller that turns on the sheet sensor when a maintenance mode is selected or a specified malfunction is detected and the cover opening / closing sensor detects that the opening / closing cover has been opened. Effect of the Invention

[0007] According to the present invention, an image forming apparatus that improves visibility of the inside of the apparatus during maintenance can be obtained at low cost.

[0008] The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a side view showing a part of the internal mechanical configuration of an image forming apparatus according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a block diagram showing a part of the electrical configuration of the image forming apparatus according to the embodiment of the present invention. [Diagram 3] FIG. 3 is a diagram showing an example of the positions of a cover and a sensor provided on the housing of the image forming apparatus according to the embodiment of the present invention. [Figure 4] FIG. 4 is a flowchart illustrating the operation of the image forming apparatus shown in FIGS. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0011] Fig. 1 is a side view showing a part of the internal mechanical configuration of an image forming apparatus according to embodiment 1 of the present invention. The image forming apparatus shown in Fig. 1 is a device having an electrophotographic printing function, such as a printer, a facsimile machine, a copier, or a multifunction machine.

[0012] The image forming apparatus of this embodiment has a tandem type color developing device. This color developing device includes photoconductor drums 1a to 1d, exposure devices 2a to 2d, and developing devices 3a to 3d. The photoconductor drums 1a to 1d are photoconductors corresponding to the four toner colors of cyan, magenta, yellow, and black.

[0013] The exposure devices 2a to 2d are devices that irradiate the photoconductor drums 1a to 1d with a laser beam while scanning it to form an electrostatic latent image. The laser beam scans in a direction (main scanning direction) perpendicular to the rotation direction (sub-scanning direction) of the photoconductor drums 1a to 1d. The exposure devices 2a to 2d have a laser scanning unit including a laser diode as a light source of the laser beam and optical elements (lenses, mirrors, polygon mirrors, etc.) that guide the laser beam to the photoconductor drums 1a to 1d.

[0014] Furthermore, around the photoconductor drums 1a to 1d, there are arranged a charger such as a scorotron, a cleaning device, a static eliminator, etc. The cleaning device removes residual toner from the photoconductor drums 1a to 1d after the primary transfer, and the static eliminator eliminates static electricity from the photoconductor drums 1a to 1d after the primary transfer.

[0015] The developing devices 3a to 3d are equipped with toner cartridges filled with toner of four colors, cyan, magenta, yellow, and black, respectively, and developing units that attach the toner transported from a toner hopper in the toner cartridge to the photosensitive drums 1a to 1d, and form toner images by attaching the toner to the electrostatic latent images on the photosensitive drums 1a to 1d.

[0016] The magenta component of the image to be printed is developed by the photoconductor drum 1a, the exposure device 2a, and the developing device 3a, the cyan component of the image to be printed is developed by the photoconductor drum 1b, the exposure device 2b, and the developing device 3b, the yellow component of the image to be printed is developed by the photoconductor drum 1c, the exposure device 2c, and the developing device 3c, and the black component of the image to be printed is developed by the photoconductor drum 1d, the exposure device 2d, and the developing device 3d.

[0017] The intermediate transfer belt 4 is an annular image carrier (intermediate transfer body) that comes into contact with the photoconductor drums 1a to 1d and onto which the toner images on the photoconductor drums 1a to 1d are primarily transferred. The intermediate transfer belt 4 is stretched around a drive roller 5, and rotates by the drive force of the drive roller 5 from the contact position with the photoconductor drum 1d to the contact position with the photoconductor drum 1a.

[0018] As described below, the transfer roller 6 brings the conveyed paper into contact with the intermediate transfer belt 4, and performs a second transfer of the toner image on the intermediate transfer belt 4 onto the paper. The paper onto which the toner image has been transferred is conveyed to a fixing device 9, where the toner image is fixed onto the paper.

[0019] The roller 7 has a cleaning brush, and the cleaning brush is brought into contact with the intermediate transfer belt 4 to remove toner remaining on the intermediate transfer belt 4 after the toner image is transferred to paper or after calibration.

[0020] Toner concentration sensor 8 irradiates intermediate transfer belt 4 with light and detects reflected light from the surface of intermediate transfer belt 4 or the toner pattern on that surface. For example, during calibration of toner gradation, toner concentration sensor 8 irradiates a light beam onto a predetermined area of ​​intermediate transfer belt 4 (area where a toner patch for calibration is transferred), detects the reflected light of the light beam, and outputs an electrical signal according to the amount of light.

[0021] Furthermore, the image forming apparatus according to this embodiment includes a plurality of paper feed cassettes 11, 12. The paper feed cassettes 11, 12 store print sheets 101, 102, and the lift plates 21, 24 push the print sheets 101, 102 upward to abut against the pickup rollers 22, 25. The print sheets 101, 102 placed in the paper feed cassettes 11, 12 are picked up one by one from above by the pickup rollers 22, 25 onto the paper feed rollers 23, 26. The paper feed rollers 23, 26 are rollers that transport the print sheets 101, 102, which have been fed from the paper feed cassettes 11, 12 by the pickup rollers 22, 25, onto a transport path one by one.

[0022] The transport roller 27 is a transport roller on a transport path shared by the print sheets 101 and 102 transported from the paper feed cassettes 11 and 12.

[0023] The registration rollers 41 temporarily stop the paper being conveyed and convey the paper to a transfer position by the intermediate transfer belt 4 and transfer rollers 6 at the secondary paper feed timing. The secondary paper feed timing is specified by a controller 61, which will be described later, so that the toner image on the intermediate transfer belt 4 is transferred to a specified position on the paper.

[0024] The registration sensor 42 is an optical sensor that is disposed near the registration rollers 41 and detects when the print sheets 101 and 102 conveyed along the conveying path reach the registration rollers 41 .

[0025] The transport sensors 43, 44, and 45 are optical sensors that detect when the print sheets 101 and 102 transported on the transport path reach a predetermined position (the installation position of the transport sensors 43, 44, and 45). The transport sensor 43 is provided immediately before the discharge roller 43a that discharges the print sheet to the discharge tray 52 (FIG. 3), the transport sensor 44 is provided immediately before the guide changer 44a provided at the branch point of the transport path, and the transport sensor 45 is provided immediately after the fixing unit 9. For example, the transport sensors 43, 44, and 45 are reflective sensors that include a light emitting section that irradiates light to a predetermined position on the transport path and a light receiving section that receives the reflected light from the predetermined position and outputs an output signal according to the amount of light received. Therefore, when a print sheet is present at the predetermined position, the amount of light received is large, and when not, the amount of light received is small.

[0026] Furthermore, the image forming apparatus according to this embodiment includes a sheet sensor 31. The sheet sensor 31 is a sensor that is provided in the conveying path of the print sheets 101 and 102 and optically detects the print sheets. The sheet sensor 31 includes a light-emitting unit such as an LED and a light-receiving unit such as a photosensor, and the light-emitting unit irradiates the print sheets 101 and 102 with light, and the light-receiving unit receives the reflected light. The sheet sensor 31 is provided to detect the deviation of the print sheet in a direction perpendicular to the conveying direction (main scanning direction) when the print sheet is conveyed, and changes the position of the page image in the main scanning direction by a controller 61 described later so that the center of the print sheets 101 and 102 and the center of the page image to be printed on the print sheets 101 and 102 coincide with each other in the main scanning direction. Here, the sheet sensor 31 is a contact image sensor as a line sensor.

[0027] Fig. 2 is a block diagram showing a part of the electrical configuration of the image forming apparatus according to the embodiment of the present invention, and Fig. 3 is a diagram showing an example of the positions of a cover and a sensor provided on the housing of the image forming apparatus according to the embodiment of the present invention.

[0028] 2 and 3, the image forming apparatus includes an openable / closable cover 51 provided on the housing and an openable / closeable cover sensor 51a that detects the open / closed state (whether the cover has been opened) of the openable / closeable cover 51. The openable / closeable cover 51 is provided on the side of the main body facing the conveyance path, and can be opened for maintenance work such as removing a jam or cleaning a glass window (a window through which irradiated light and reflected light, described below, pass) of the sheet sensor 31.

[0029] Furthermore, as shown in Fig. 2, the image forming apparatus includes a controller 61. The controller 61 includes a computer, an ASIC (Application Specific Integrated Circuit), and the like, and realizes various processing sections with software and / or hardware, and monitors and controls internal devices such as the printing apparatus shown in Fig. 1, and also performs various data processing. For example, during printing, the controller 61 controls a driving source (not shown) that drives the rollers described above, a bias circuit that applies a primary transfer bias, the developing devices 3a to 3d, the exposure devices 2a to 2d, and the like, to develop, transfer, and fix the toner image, and to feed, transport, and discharge the print sheets 101 and 102.

[0030] During such printing, the controller 61 changes the position of the page image in the main scanning direction so that the center of the print sheet 101, 102 based on the image of the print sheet obtained by the sheet sensor 31 coincides with the center of the page image to be printed on the print sheet 101, 102.

[0031] Furthermore, when a maintenance mode is selected by a user operation on an operation panel (not shown) or a specific malfunction is detected during printing, and the cover open / close sensor 51a detects that the open / close cover 51 has been opened, the controller 61 turns on the sheet sensor 31 and irradiates light onto the inside of the image forming apparatus (particularly the conveying path, etc.). In the maintenance mode, setting values ​​are edited based on user operations, and maintenance work is performed inside the image forming apparatus.

[0032] For example, the controller 61 detects a jam of the print sheets 101, 102 based on the output signals of the conveying sensors 43, 44, 45, and when the controller 61 detects the jam and the cover opening / closing sensor 51a detects that the opening / closing cover 51 has been opened, the controller 61 turns on the sheet sensor 31.

[0033] In this embodiment, the controller 61 changes the lighting mode of the sheet sensor 31 according to the position where the jam is detected in the conveying path (for example, any of the installation positions of the conveying sensors 43, 44, and 45). As the lighting mode, the light color, continuous lighting / blinking, blinking cycle, combinations thereof, etc. are set.

[0034] For example, when a jam is detected, if only the transport sensor 43 of the transport sensors 43, 44, and 45 detects the print sheet, the sheet sensor 31 is continuously lit in red, if only the transport sensors 43 and 44 detect the print sheet, the sheet sensor 31 is intermittently lit (blinks) in red, and if only the transport sensor 45 detects the print sheet, the sheet sensor 31 is continuously lit in blue. Then, when all of the transport sensors 43, 44, and 45 no longer detect the print sheet, the sheet sensor 31 is continuously lit in white.

[0035] Next, the operation of the image forming apparatus will be described below. Fig. 4 is a flow chart for explaining the operation of the image forming apparatus shown in Figs.

[0036] Normally, the opening / closing cover 51 is in a closed state, and is opened by a user or the like when, for example, a jam occurs in the conveying path of the print sheets 101, 102. When the opening / closing cover 51 is opened, the level of the output signal of the cover opening / closing sensor 51a changes, and the controller 61 detects that the opening / closing cover 51 is opened and in the open state based on the change in the level of the output signal of the cover opening / closing sensor 51a.

[0037] The controller 61 monitors whether the maintenance mode has been selected (step S1) and whether a malfunction such as a jam has been detected (step S2). When the maintenance mode has been selected or a malfunction has been detected, the controller 61 monitors whether the opening / closing cover 51 has been opened (step S3).

[0038] When it is detected that the opening / closing cover 51 is opened, the controller 61 turns on the sheet sensor 31 (step S4).

[0039] After the sheet sensor 31 starts to light up, the controller 61 monitors whether the opening / closing cover 51 is closed or not (step S5), and keeps the sheet sensor 31 lit until the opening / closing cover 51 is closed, and turns off the sheet sensor 31 when the opening / closing cover 51 is closed (step S6).

[0040] As described above, according to the embodiment, the sheet sensor 31 is provided in the transport path of the print sheets 101, 102 and optically detects the print sheets 101, 102. The cover open / close sensor 51a detects that the open / close cover 51 has been opened. When the maintenance mode is selected or a predetermined malfunction is detected, the controller 61 turns on the sheet sensor 31 if the cover open / close sensor 51a detects that the open / close cover 51 has been opened.

[0041] As a result, the sheet sensor 31 provided for printing is turned on during maintenance without providing a dedicated lighting means, and therefore visibility of the inside of the apparatus during maintenance is improved at low cost.

[0042] It should be noted that various changes and modifications to the above-described embodiments will be apparent to those skilled in the art. Such changes and modifications may be made without departing from the spirit and scope of the subject matter and without diminishing its intended advantages. In other words, such changes and modifications are intended to be included within the scope of the claims.

[0043] For example, in the above embodiment, the sheet sensor 31 is turned on during maintenance, but in addition to the sheet sensor 31, the transport sensors 43, 44, and 45 may also be turned on. [Industrial Applicability]

[0044] The present invention is applicable to, for example, an image forming apparatus. [Explanation of symbols]

[0045] 31 Sheet Sensor 43,44,45 Transport sensor 51 Opening and closing cover 51a Cover opening / closing sensor 61 Controller

Claims

1. a sheet sensor provided in a conveying path of the print sheet for optically detecting the print sheet; Opening and closing cover, a cover opening / closing sensor for detecting when the opening / closing cover is opened; a controller that turns on the sheet sensor when the cover opening / closing sensor detects that the opening / closing cover is opened in a case where a maintenance mode is selected or a predetermined malfunction is detected; An image forming apparatus comprising:

2. The conveyor further includes conveyance sensors provided at a plurality of positions on the conveying path, the openable cover is provided facing the transport path, The controller detects a jam of the print sheet based on an output signal of the transport sensor, the controller turns on the sheet sensor when the cover open / close sensor detects that the open / close cover has been opened when the jam is detected; 2. The image forming apparatus according to claim 1,

3. 3. The image forming apparatus according to claim 2, wherein the controller changes a lighting state of the sheet sensor in accordance with a position in the conveying path where the jam is detected.

4. 4. The image forming apparatus according to claim 1, wherein the sheet sensor is provided to detect a deviation of the print sheet in a direction perpendicular to a conveying direction when the print sheet is conveyed.

Images