JP6554941B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus that does not have an automatic duplex conveyance mechanism.

  Conventionally, an image forming apparatus such as a printer or a copying machine has an automatic duplex conveying mechanism (hereinafter referred to as a duplex unit) for performing duplex printing. However, the installation of the duplex unit increases the cost and the size of the apparatus. There was a problem that it was not possible to save space by making it easier. In order to solve these problems, an image forming apparatus having no duplex unit is known at present.

  An image forming apparatus that does not have a duplex unit enables duplex printing by selecting a so-called “manual duplex mode”. The manual duplex mode is switched by pressing a button from the operation panel of the image forming apparatus. For example, printing of odd pages is started. After the paper is passed, the user returns the front side to the back side, resets it to the paper feed cassette, and presses the copy button to print the remaining even pages and complete double-sided printing. In such an image forming apparatus that does not include a duplex unit, a manual duplex printing mode is provided, and a duplex printing method by a user's manual operation is already known.

  However, in the conventional manual double-side mode mechanism, it is difficult to understand the orientation of the paper set by the user and whether the front side or the back side of the printing paper is set, and there is a possibility of erroneous printing. In the case of the printing method using the manual duplex mode described above, for example, after printing odd pages, paper is set in the paper cassette to print even pages, but there is a situation where the printing surface is confusing. In some cases, even-numbered pages are printed on odd-numbered pages without knowing the printing surface of even-numbered pages.

  In Patent Document 1, in an image forming apparatus that does not have a duplex unit, for the purpose of performing printing using a manual duplex mode mechanism, after a single-side printed sheet is stacked on a discharge tray, a second feeding is performed. A mechanism is disclosed that places a sheet on a paper tray, selects either the paper feed mode or the manual paper feed mode, and prints the other side of the paper that has been fed. Although the manual double-sided mode mechanism is used, the above-described problem of preventing the user from making a mistake on the printed side cannot be solved.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an image forming apparatus that does not have a double-side unit mechanism and that can reduce erroneous printing in the manual double-side mode in an image forming apparatus that does not have a double-side unit mechanism.

In order to achieve the above object, an image forming apparatus according to the present invention is an image forming apparatus that does not have an automatic double-sided conveyance mechanism, and includes a paper feed unit, a paper discharge unit that discharges printed paper, and an image forming device. It has a manual feed tray that can be mounted on the main body at two mounting locations, and a plurality of sensors that detect whether the manual feeding tray is set at the upper or lower mounting location, and is set to manual duplex mode. In this case, the sheet fed from the sheet feeding unit and image-formed on the first surface of the sheet is discharged to the manual feed tray mounted on the upper mounting position, and the manual tray is mounted on the lower mounting position. Then, paper is fed from the manual feed tray, formed on the second side of the paper and discharged to the paper discharge unit . When manual duplex printing is performed, the image is reversed by at least one sensor. Tore Detecting a set direction, characterized in that.

  According to the present invention, it is possible to prevent an error in the printing surface during double-sided printing.

FIG. 3 is a schematic configuration diagram at the time of single-sided printing in an image forming apparatus (in-body discharge) that does not have a duplex unit according to an embodiment of the present invention. 1 is a configuration diagram of a reading unit of an image forming apparatus according to an embodiment of the present disclosure. FIG. 3 is a diagram illustrating an example of an operation panel of the image forming apparatus according to the embodiment of the present disclosure. FIG. 2 is a schematic configuration diagram of a control unit in the image forming apparatus according to an embodiment of the present disclosure. FIG. 2 is a schematic configuration diagram at the time of manual duplex printing in the image forming apparatus according to an embodiment of the present invention. FIG. 2 is a schematic configuration diagram of the image forming apparatus according to an embodiment of the present invention during manual duplex printing. FIG. 3 is a flowchart diagram for single-sided printing and manual double-sided printing of the image forming apparatus according to the embodiment of the present invention. FIG. 2 is a schematic diagram when a manual feed tray is attached to the apparatus main body in the image forming apparatus according to the embodiment of the present invention. 1 is a schematic configuration diagram of a manual feed tray used in an image forming apparatus according to an embodiment of the present invention. FIG. 5 is a diagram for describing an image direction during manual duplex printing in the image forming apparatus according to the embodiment of the present disclosure. FIG. 5 is a diagram for explaining a manual tray detection method during manual duplex printing in the image forming apparatus according to the embodiment of the present disclosure. FIG. 5 is a diagram illustrating a manual tray detection method during manual duplex printing in the image forming apparatus according to an embodiment of the present invention. FIG. 5 is a diagram for explaining a manual tray detection method during manual duplex printing in the image forming apparatus according to the embodiment of the present disclosure.

An embodiment of the present invention will be described.
The present invention has the following characteristics for preventing erroneous setting of printing paper in the manual duplex mode in an image forming apparatus having no duplex unit. In short, when the manual double-side mode is set, in addition to the paper discharge tray that discharges downward on the image surface, the paper is switched upward on the image surface by switching the transport path onto a simple tray mounted above the manual paper feed tray. A feature is that double-sided printing is possible by printing the discharged paper directly on the lower manual paper feed tray. Accordingly, the printing surface can be set as it is, and printing can prevent erroneous printing due to a user's paper setting mistake.

The features of the present invention will be described in detail with reference to the following drawings.
FIG. 1 is a schematic view of one-side printing in an image forming apparatus (in-body discharge form) that does not have a duplex unit according to an embodiment of the present invention. The apparatus main body 1 of the image forming apparatus shown in FIG. 1 mainly has a reading system for obtaining paper information, a transport system for transporting paper, a development system for copying on paper, and a fixing system for fixing toner. Yes.

  The reading system includes a reading device 21 for obtaining paper information. Further, the transport system includes a paper feed cassette 3 for storing paper. The transport system transports the paper, the paper feed cassette detection sensor 4 for detecting the paper stored in the paper feed cassette 3, the pickup roller 5 for feeding the paper stored in the paper feed cassette 3, and the paper. Conveying rollers 6a and 6b are provided. Also, paper discharge rollers 14a and 14b for discharging the paper into the cylinder, and a paper conveyance direction switching claw 13 for switching the paper conveyance direction from the cylinder to the manual tray side for discharging onto the manual tray 16. And have. Further, it has manual tray discharge rollers 15 a and 15 b for transporting paper onto the manual tray 16. Furthermore, it has a manual feed tray 16 that can be attached to and detached from the apparatus main body 1. Then, an upper manual feed tray detection sensor 17 for detecting that the manual feed tray 16 is set at the upper discharge outlet of the apparatus main body 1 and a setting of the manual feed tray 16 at the lower paper supply opening of the apparatus main body 1 are detected. And a lower manual feed tray detection sensor 18. In addition, the manual feed tray 16 is set in the lower paper feed opening. In addition, manual feed tray paper feed rollers 19 a and 19 b for conveying paper on the manual feed tray 14 and a manual feed tray paper feed port pickup roller 22 are provided. Further, manual tray upper sheet discharge port receiving portions 167a and 167b for receiving the manual tray when setting the manual feed tray 16 and manual tray lower sheet supply port receiving portions 168a and 168b are provided. A main motor as a driving source of the roller is provided, but illustration is omitted.

  The development system includes a photoconductor 7 for transferring toner and a charging charger 8 for applying a charge to the photoconductor 7. The image forming apparatus further includes a transfer roller 9 for transferring toner to a sheet, a developing unit 10 for supplying toner to the photoconductor 7, and a writing unit 11 for irradiating an image with a laser. The fixing system includes fixing rollers 12a and 12b for fixing toner on the paper.

  FIG. 2 shows a configuration of a reading unit mounted on the apparatus main body 1. The reading device 21 is mounted on the upper part of the image forming apparatus, and includes a contact glass 202 on which a sheet is placed and a light source 203 that illuminates the sheet. Further, it includes a first mirror 204a, a second mirror 204b, a third mirror 204c, a lens 205, an image reading CCD 206a, and an image processing substrate 206b for reflecting light reflected from the paper.

  FIG. 3 shows a main configuration of the operation panel 2 provided on the upper part of the apparatus main body 1. In the figure, reference numeral 211 denotes a display unit 211 for displaying image processing system settings and the like. The display unit 211 includes a single-sided printing mode setting key 212 for setting the single-sided printing mode and a manual double-sided printing setting key 213 for setting the manual double-sided printing mode. In addition, a start key 215 for executing printing, a clear key 214 for executing printing stop, and an image inversion key 216 are provided.

  FIG. 4 is a configuration diagram of the control unit of the apparatus main body 1. As a configuration of the control unit in FIG. 4, by executing a control program of a computer program, a CPU (Central Processing Unit) that controls driving of each unit, a ROM (Read Only Memory) that stores various data in a rewritable manner, An interface that connects a RAM (Random Access Memory) and a sensor of the image forming apparatus is provided. Then, via the interface, the paper discharge unit, paper feed unit, reading unit switching claw driving unit 301, upper manual tray detection sensor 17, paper cassette detection sensor 302, lower manual tray detection sensor 18, and read drive unit 303. Connected and controls each part.

The printing process in the image forming apparatus having no duplex unit with the above configuration will be described below.
<Single-sided printing>
FIG. 1 shows a sheet conveyance path in single-sided printing, and shows a series of printing flows of the image forming apparatus. When copying with the configuration of the image forming apparatus as described above, first, the single-sided printing mode setting key 212 on the operation panel is pressed, the original to be copied is set on the contact glass 202 of the reading apparatus 21, and the original is read by the pressure plate 20. Press down and close the document with the pressure plate 20. Although not shown, the pressure plate 20 can be opened and closed. When the start key 215 on the operation panel 2 is pressed, the scanner unit is driven, and the light source 203 and the first mirror 204a emit light and run. The light source 203 and the first mirror 204a travel, reflect light reflected from the document surface, and reflect to the first mirror 204a, the second mirror 204b, and the third mirror 204c, and pass through the lens 205 to read the image CCD 206a and the image processing board 206b. And read the document contents.

  The read information is output from the image recording to the writing unit 11 as an optical image signal. An image signal from the image processing unit of the writing unit 11 is converted into an optical signal, and an electrostatic latent image is formed by scanning and exposing the surface of the uniformly charged photoreceptor 7 based on the optical signal. . Next, printing is started by the following process. Adjustment is performed to remove the potential when the charge is applied by the toner or the charging charger 8 remaining on the photosensitive member 7 remaining during the previous printing of the photosensitive member 7. When the above adjustment is completed, a (+) charge is applied to the photosensitive member 7 by the charging charger 8, and electrostatic charging is performed by irradiation of image information from the writing unit 11 (dotted arrow from the writing unit 11 to the photosensitive member 7 in the figure). A latent image is recorded on the photoreceptor 7. Accordingly, the paper previously stored in the paper feed cassette 3 rises to the pickup roller 5 and comes into contact with the paper. The pick-up roller 5 in contact is conveyed to the paper feed rollers 6a and 6b by rotational driving. Next, the paper that has reached the paper feed rollers 6a and 6b is transported to the photoconductor 7, and at the same time as the photoconductor 7 is rotationally driven, the (−) charge having a property opposite to that of the photoconductor 7 of the transfer roller 9 is obtained. The toner is transferred onto the paper by the reverse bias rotational drive. Next, rotation is performed while applying pressure with the fixing rollers 12a and 12b heated to the toner melting point temperature of the fixing rollers 12a and 12b, so that the toner is fused to the paper onto which the toner has been transferred. The sheets welded by the fixing rollers 12a and 12b are guided in the in-cylinder sheet discharge direction by the sheet conveyance direction switching claw 13 that is switched so as to be discharged in the in-cylinder sheet discharge direction. The paper is discharged into the cylinder of the image forming apparatus by driving.

<Conventional manual duplex printing>
FIG. 5 illustrates a case where a conventional manual duplex printing technique is employed in an image forming apparatus having no duplex unit according to the present invention. A sheet on which printing on one side (first side) has been finished is placed in the cylinder of the image forming apparatus by following the paper conveyance route shown in FIG. When the user completes the single-sided printing on the sheet cassette 3 again, the set sheet is detected by the sheet cassette detection sensor 4. Pressing the start key 215 on the operation panel 2 starts printing on the remaining side (second side), the paper passes through the transport route again, and printing on both sides ends. In this case, when the discharged paper is reset in the paper feed cassette 3 by the user, it is difficult to determine the printing surface, and a setting error or the like occurs.

<Manual duplex printing of the present invention>
Manual duplex printing according to the present invention will be described. When starting manual duplex printing, first, the manual duplex printing setting key 213 is pressed on the operation panel 2 in the image forming apparatus. As a result, the mode is switched from the single-sided printing mode to the manual double-sided printing, and the paper conveyance direction switching claw 13 is directed from the in-body discharge direction toward the manual feed tray, and the paper is discharged to the manual feed tray. FIG. 5 (in manual duplex printing or single-sided printing) shows that the direction of the paper transport direction switching claw 13 is switched from the dotted line portion to the solid line. This is realized by the switching claw driving means 301 shown in FIG.

  Next, paper is set in the paper feed cassette 3, the paper feed cassette detection sensor 4 detects the paper, and when the start key 215 of the operation panel 2 is pressed, printing on one side is started. In the image forming apparatus according to the present invention, a manual feed tray lower sheet feed port 102 (see FIG. 8) is provided in addition to the manual feed tray upper sheet discharge port 101 (see FIG. 8). If the manual feed tray 16 is set in the paper feed port of the lower manual feed tray of the image forming apparatus, a guidance such as “Please set the manual feed tray in the upper paper feed port” is displayed on the operation panel 2. Displayed on the part 211.

  An upper manual feed tray detection sensor 17 and a lower manual feed tray detection sensor 18 are provided in the manual feed tray upper paper discharge port 101 and the manual feed tray lower paper feed port 102, respectively. Then, when the manual feed tray 16 is set in the manual feed tray lower sheet feeding port 102, a control that cannot perform printing is incorporated. Therefore, when the manual feed tray 16 is set in the manual feed tray upper discharge port 101, for example, a guidance display “Press the start key to start printing” is displayed on the display unit 211 of the operation panel 2. Thereby, an optimal set position is detected, and guidance display is made on the operation unit.

  The manual feed tray 16 is attached as shown in FIG. 6 by being hooked by the manual feed tray upper discharge port receiving portions 167a and 167b and the manual feed tray lower paper feed port receiving portions 168a and 168b. When it is detected that the manual feed tray 16 is set in the manual feed tray upper discharge port 101, the display unit 211 of the operation panel 2 indicates, for example, “Is the size of the paper guide plate provided in the manual feed tray appropriate?” Is displayed. This is to prevent the paper from contacting the guide plate and not being ejected well due to jam or paper breakage when the paper size setting of the guide plate provided in the manual feed tray 16 is different from the paper size to be printed. Such a control is provided. The two paper guide plates mounted on the manual feed tray 16 are provided with a slide mechanism as shown in FIG. 9 described later, and can be displaced in a direction in which the paper guide plates are close to each other or in a direction away from each other.

  When the user sets the manual feed tray 16 in the manual feed tray upper discharge port 101, a guidance display on the display unit 211 of the operation panel 2 ready for printing appears. For example, the phrase “Is the size of the paper guide plate appropriate?” And the phrase “please press the start key”, for example, are alternately switched and displayed on the display unit 211. This informs the user that printing is possible and whether the guide plate size and paper size are appropriate. Then, when the user presses the start key 215, one-sided printing of manual duplex printing is performed by the printing process as shown in FIG. 1, and a sheet of paper on which one side is printed is set in the manual feed tray upper discharge port 101. 16 is discharged.

  Next, when the single-sided printing is finished and the paper is discharged from the manual tray upper paper discharge port 101 to the manual tray 16, the display unit 211 of the operation panel 2 displays, for example, “Remove the manual tray and set it in the lower paper feed port. Please display ". When the user inserts the manual feed tray 16 into the manual feed tray lower paper feed slot 102, for example, “Please prepare the paper with the guide plate of the manual feed tray”, for example, “Press the start key to start printing”. Such guidance is displayed on the display unit 211. When the sensor detects that the manual feed tray 16 is set, the paper transport direction switching claw 13 is driven by the switching claw driving means 301 to switch from the manual tray discharge direction to the in-body discharge direction (see FIG. 6: manual duplex printing). : Drives like the dotted line during double-sided printing). At this point, the start key 215 can be pressed. For example, the display unit 211 alternately displays a message such as “Please prepare paper in the manual feed tray with a guide plate” and a message such as “Please press the start key to start printing”. Is displayed. As a result, the user is notified of the printable state and the sheet alignment. When the user presses the start key 215, the manual feed tray paper feed port pickup roller 22 and the manual feed tray paper feed rollers 19a and 19b are started to rotate, and the paper is conveyed into the image forming apparatus main body. The printing process is the same as single-sided printing, and the paper is discharged into the cylinder of the image forming apparatus, and double-sided printing is completed. FIG. 7 shows the detection of the manual feed tray, the printing flow, and the display flow of the display unit 211 of the operation panel 2.

  FIG. 8 is a schematic view when the manual feed tray 16 according to the embodiment of the present invention is attached to the main body, and FIG. 9 is a schematic view of the manual feed tray 16. The manual feed tray 16 includes a manual feed plate 161 for placing paper and paper guide plates 162a and 162b for preparing printed paper. In addition, detection notches 163a, 163b, and 163c, paper guide plate notches 164a and 164b, guide shafts 165a and 165b, sliders 166a and 166b, and a manual feed tray lower sheet feed port receptacle 168a and 168b are provided. Yes. The paper guide plates 162a and 162b are slidable according to the paper size. The guide shafts 165a and 165b are slidable by a slider 166a integrated with the paper guide plate 162a and a slider 166b integrated with the paper guide plate 162b. The paper guide plates 162a and 162b are displaced in directions close to each other or in directions away from each other. Further, manual tray upper discharge outlet receiving portions 167a and 167b for attaching the manual tray 16 to the manual tray upper discharge opening 101 and the manual tray lower supply opening 102 of the apparatus main body 1 of the image forming apparatus are provided. In addition, the sheet load applied to the manual feed tray 16 can be withstood. In the case of double-sided printing in the present embodiment, single-sided printing is finished, the paper is placed on the manual feed tray 16 as it is, and the paper is reversed to the manual feed tray lower sheet feed port 102 to set the manual feed tray 16 for printing. The tray 16 can be set. Then, it is attached so as to be hooked by the manual tray upper sheet discharge port receiving portions 167a and 167b provided in the manual tray upper sheet discharge port 101 and the manual tray lower sheet feed port 102.

When double-sided printing is performed based on these, there are cases where the image orientation of double-sided printing is different. In manual double-sided printing according to the present invention, double-sided printing is possible only by attaching and detaching the manual feed tray. Each case will be described.
<Image orientation is the same for duplex printing>
First, when the user depresses the manual duplex printing setting key 213 on the operation panel 2, the mode is switched to manual duplex printing. For example, “Set the manual feed tray to the upper paper outlet on the display unit 211 of the operation panel 2. "Is displayed. The detection of the manual feed tray 16 is detected by the upper paper discharge port manual tray detection sensors 171a and 171b provided in the manual feed tray upper paper discharge port 101. The manual feed tray 16 is provided with detection cutouts 163a, 163b, and 163c, and the sensor position of the manual feed tray upper discharge port 101 is set as shown in FIGS. The detection of the manual feed tray 16 may be performed by setting the manual feed tray in the direction of the manual feed tray and the manual feed tray lower sheet feeding port 102. , 163c. The display unit 211 displays, for example, “Please set the manual feed tray in the upper paper discharge port”, and 171a detects the manual feed tray 16 and 171b is not detected. Please press the key. " This state is set as a correct manual feed tray. When the manual feed tray 16 is inverted and set in the manual feed tray upper paper discharge port 101, both the upper paper discharge port manual feed tray detection sensors 171a and 171b detect the manual feed tray 16. Then, for example, a message such as “the manual feed tray is reversed” is displayed, and an erroneous setting of the manual feed tray 16 is detected.

  Next, when the manual feed tray 16 is set in the manual feed tray lower sheet feed opening 102, both of the manual feed tray lower sheet feed opening detection sensors 181 a and 181 b detect the manual feed tray 16. Then, for example, a message such as “Please set the manual feed tray in the upper paper discharge port” is displayed on the display unit 211. When the paper is set upside down at the manual feed tray lower paper feed slot 102, it is not detected by the manual feed tray lower paper feed slot detection sensor 181a. However, the manual feed tray lower paper feed opening detection sensor 181b detects it. Then, for example, a phrase such as “Please set the manual feed tray upside down in the upper discharge port” is displayed on the display unit 211. In this way, when performing single-sided printing of manual duplex printing, the upper discharge port manual tray detection sensor 171a detects the manual tray 16. The upper discharge port manual tray detection sensor 171b recognizes that the manual tray 16 is not detected as a correct setting method of the manual tray 16 in the manual tray upper discharge port 101. Then, when the start key 215 is pressed, printing on one side is started and discharged to the manual feed tray 16.

  Next, detection of the manual feed tray 16 when the single-sided printing is completed and the manual feed tray 16 is set in the manual feed tray lower sheet feeding port 102 will be described. When single-sided printing is completed, the display unit 211 displays a message such as “Please set a manual feed tray at the lower paper feed slot”. When the manual feed tray 16 remains set in the manual feed tray upper paper discharge port 101, the upper paper discharge port manual feed tray detection sensor 171a detects the manual feed tray 16, for example, “Set the manual feed tray to the lower paper feed port. "Please do" is displayed. When the manual tray 16 is set to the manual feed tray lower paper feed port 102 in the same direction, the manual feed tray lower paper feed port detection sensors 181a and 181b detect the manual feed tray 16. Then, for example, a message “please press the start key” is displayed on the display unit 211, and when the image orientation of manual duplex printing is the same, it is recognized that the detection is correct. When the manual feed tray 16 is inverted and set in the manual feed tray lower paper feed opening 102, the manual feed tray lower paper feed opening detection sensor 181a does not detect the manual feed tray 16. Then, the manual feed tray lower sheet feed opening detection sensor 181b detects the manual feed tray 16, and displays a message such as “Please reverse the manual feed tray” on the display unit 211. Thereby, an erroneous setting of the manual feed tray 16 can be recognized. When the image directions are the same, the manual tray 16 is set in the manual feed tray lower sheet feeding port 102 as it is as described above. Then, the manual feed tray lower paper feed opening detection sensors 181a and 181b detect the manual feed tray 16, and for example, a message “Please press the start key” is displayed on the display unit 211. Then, in order to recognize that the detection is correct when the image orientation of the manual duplex printing is the same, the user presses the start key 215, the sheet is discharged into the cylinder, and the manual duplex printing ends.

<When the image direction is reversed>
Next, a description will be given of the case where the character orientation of the paper is paper reversal as shown in FIG. When the user selects duplex printing and wants to reverse the image direction, first the manual duplex printing setting key 213 on the operation panel 2 is pressed to set manual duplex printing. Next, the image inversion key 216 on the operation panel 2 is pressed to set image inversion. In single-sided printing up to the manual tray 16 at the manual tray upper paper discharge port 101, the manual tray 16 at the manual tray upper paper discharge port 101 described above is detected, and an erroneous setting of the user's manual tray is detected. When single-sided printing is completed, the display unit 211 displays a message such as “Please set a manual feed tray at the lower paper feed slot”. Then, the manual tray 16 is set in the manual feed tray lower paper feed slot 102. If the sensor is detected by both the manual feed tray lower paper feed slot detection sensors 181a and 181b, for example, "Please reverse the manual feed tray" Is displayed. Then, when the manual feed tray lower paper feed opening detection sensor 181a does not detect the manual feed tray 16 and the manual feed tray lower paper feed opening detection sensor 181b detects the manual feed tray 16, a phrase such as “Please press the start key” is displayed. Is displayed. By pressing the image reversal key 216, the detection pattern of the manual feed tray 16 after the one-side printing is completed is reversed. The state where the manual feed tray lower paper feed opening detection sensor 181a does not detect and the manual feed tray lower paper feed opening detection sensor 181b is detected is recognized as the correct setting method of the manual feed tray 16. Thus, the detection means of the manual feed tray 16 differs depending on whether the image direction is the same or reversed, and the setting of the detection means can be switched by pressing the image reverse key 216 when manual duplex printing is set.

  The present invention is not limited to the embodiments described above, and many variations are possible by those having ordinary knowledge in the art within the technical idea of the present invention.

1: Device main body 2: Operation panel 3: Paper feed cassette 4: Paper feed cassette detection sensor 5: Pickup rollers 6 a and 6 b: Paper feed roller 7: Photoconductor 8: Charger charger 9: Transfer roller 10: Development unit 11: Writing Units 12a, 12b: Fixing roller 13: Paper transport direction switching claws 14a, 14b: Paper discharge rollers 15a, 15b: Manual feed paper discharge roller 16: Manual feed tray 17: Upper manual feed tray detection sensor 18: Lower manual feed tray detection sensor 19a, 19b: Bypass tray feed roller 20: Pressure plate 21: Reading device 22: Bypass tray feed port pickup roller 101: Bypass tray upper discharge port 102: Bypass tray lower feed port 161: Bypass plates 162a, 162b: Paper guide plate 163a, 163b, 163c: Notch for detection 164a, 164b: paper guide plate notches 165a, 165b: guide shafts 166a, 166b: sliders 167a, 167b: manual tray upper paper discharge outlet receivers 168a, 168b: manual tray lower paper supply outlet receivers 171a, 171b: Upper discharge port manual tray detection sensors 181a, 181b: Manual tray lower paper feed detection sensor 202: Contact glass 203: Light source 211: Display unit 212: Single-sided printing mode setting key 213: Manual duplex printing setting key 214: Clear key 215 : Start key 216: Image reversal key 301: Switching claw drive means 302: Paper feed cassette detection sensor 303: Reading drive means

JP-A-9-218547

Claims (3)

An image forming apparatus having no automatic duplex conveying mechanism,
A paper feed unit, a paper discharge unit that discharges printed paper, a manual feed tray that can be attached to the image forming apparatus main body at two upper and lower mounting locations, and the manual feed tray that is set at the upper or lower mounting location. A plurality of sensors for detecting whether or not
When the manual duplex mode is set, the sheet fed from the sheet feeding unit and image-formed on the first side of the sheet is discharged to the manual feed tray mounted on the upper mounting position,
When the manual feed tray is mounted at the lower mounting position, paper is fed from the manual feed tray, formed on the second surface of the paper, and discharged to the paper discharge unit .
When the image direction is reversed during manual duplex printing, the setting direction of the manual feed tray is detected by at least one sensor.
An image forming apparatus. The image forming apparatus according to claim 1.
The manual feed tray is detachable at the upper and lower mounting locations.
An image forming apparatus. The image forming apparatus according to claim 1, wherein
The guidance display according to the detection result of the sensor is performed.
An image forming apparatus.