JP6225865B2 - Image forming apparatus and cassette open / close detection method - Google Patents

Description

  The present invention relates to an image forming apparatus and a cassette open / close detection method, and more specifically, by effectively using an existing select signal line, standby power in the power saving mode is reduced without increasing the signal line, and cassette open / close is performed. The present invention relates to an image forming apparatus capable of detection and a cassette open / close detection method.

  Conventionally, electrical connection between a printer engine of an image forming apparatus and a detachable sheet feeding apparatus is performed via communication. In this configuration, when the power supplied to the sheet feeding apparatus is interrupted in the power saving mode, it is not possible to detect whether the sheet stacking unit of the sheet feeding apparatus is attached or detached. Therefore, when the user changes the paper size during the power saving mode, the printer engine can only recognize the information of all sheet feeding devices via serial communication when returning from the power saving mode. There is a problem that cannot be done.

  On the other hand, the sheet stacking means is usually attached and detached rarely, but the shift to the power saving mode is frequently performed. Therefore, if the user does not detect attachment / detachment of the sheet stacking unit in the power saving mode, the recovery time cannot be returned from the power saving mode until all information of the sheet feeding device is updated when returning from the power saving mode. There is a problem that becomes longer.

  In order to solve this problem, Japanese Patent Laying-Open No. 2006-326861 (Patent Document 1) discloses an image forming apparatus in which a plurality of building paper feeders can be installed. In the power saving mode, the CPU of the paper feeder is stopped. However, since serial communication (clock, data, select signal) cannot be used, a technique is disclosed in which a control line is separately provided to monitor the opening / closing of the cassette from the engine of the printer main body. As a result, it is possible to reduce standby power during the power saving mode and reduce the return time from the power saving mode to achieve improved reliability and usability.

  Japanese Patent Laying-Open No. 2006-126959 (Patent Document 2) discloses an electronic device including mode switching means for switching each input / output port of an IC having a power saving mode to an input mode or an output mode. . Japanese Patent Laid-Open No. 2002-29117 (Patent Document 3) discloses a technique for supplying power only to a member that requires operation. Further, Japanese Patent Laid-Open No. 2003-89440 (Patent Document 4) discloses a technique for directly connecting only a detection signal from an insertion / extraction detection unit of a paper feed unit to an apparatus main body without using a relay board. Japanese Patent Application Laid-Open No. 2002-172832 (Patent Document 5) discloses a technique including a cassette opening / closing detection unit capable of detecting opening / closing of a cassette even in a sleep mode. Moreover, as a related prior art document, there is JP 2008-185784 A (Patent Document 6).

JP 2006-326861 A JP 2006-126959 A JP 2002-29117 A JP 2003-89440 A JP 2002-172832 A JP 2008-185784 A

  However, in the technique described in Patent Document 1 described above, it is necessary to provide a control line separately from the signal line used in serial communication, and there is a problem that a cost increase such as an increase in the number of signal lines occurs. . Further, even in the technique described in Patent Documents 2-6 described above, it is unclear whether the cost can be reduced by using an existing signal line.

  Therefore, the present invention has been made to solve the above problem, and by effectively using an existing select signal line, the standby power in the power saving mode is reduced without increasing the signal line, and the cassette is used. An object of the present invention is to provide an image forming apparatus capable of detecting opening and closing and a cassette opening and closing detection method.

In order to solve the above-described problems and achieve the object, the image forming apparatus according to the present invention is communicably connected via a plurality of paper cassettes and a plurality of select signal lines. An image forming apparatus that stops power supply to a paper feed cassette and maintains power supply to a main body, and employs the following configuration.

That is, the image forming apparatus, when transition to the power saving state, and the signal receiving means own apparatus main body and can receive a signal from the paper feed cassette via the plurality of select signal lines, given the paper feed When the cassette is opened, corresponding to the open state of the paper feed cassette, signal transmission means for transmitting a signal from the paper feed cassette to the apparatus main body via the plurality of select signal lines, and the plurality of select signals When a signal from the plurality of sheet cassettes is received via a line, an open detection means for detecting that the specific sheet cassette corresponding to the signal is opened, and the plurality of select signal lines are: In the formable state, when the apparatus body designates a specific paper feed cassette among a plurality of paper feed cassettes, one of the plurality of select signal lines is set to logic “1”, and the others are Any one of the sheet feeding cassettes having the logic “0” and the logic “1” select signal line designated is wired so as to have the same port position, and the signal transmitting means is in the image formable state. A signal line for connecting a cassette open / close detection switch that is electrically connected to and detached from the select signal line corresponding to logic “1” corresponding to the opening / closing of the paper feed cassette, and the signal line are electrically connected. The select signal line includes a power supply unit that applies a predetermined voltage even in a power saving state .

  The buffer provided in the select signal line between the apparatus main body and the paper feed cassette is provided with a bidirectional signal switching function, and the signal receiving means, when in a power saving state, The direction of the signal from the sheet cassette to the apparatus main body is switched to one direction so that the apparatus main body can receive a signal from the sheet cassette via the select signal line.

  Further, the present invention is an image that is communicably connected to a paper feed cassette via a select signal line, and when the power saving state is entered, the power supply to the paper feed cassette is stopped and the power supply to the main body is maintained. It can be provided as a cassette opening / closing detection method of the forming apparatus.

That is, the cassette opening and closing sensing method, when transition to the power saving state, a step that allows receiving the signal from the paper feed cassette own apparatus main body via a plurality of select signal lines, given the paper feed cassette When opened, corresponding to the open state of the sheet feeding cassette, and sending a signal to the own apparatus main body from the sheet feeding cassette via the plurality of select signal lines, via the plurality of select signal lines Receiving a signal from the plurality of paper feed cassettes, detecting that the specific paper feed cassette corresponding to the signal is in an open state, and the plurality of select signal lines in an image formable state, When the apparatus body designates a specific paper feed cassette among a plurality of paper feed cassettes, one of the plurality of select signal lines is set to logic “1”, and the other is discussed. All the sheet cassettes designated with “0” and the logic “1” select signal line are wired so as to have the same port position, and are electrically connected to the signal line. The select signal line is wired so as to apply a predetermined voltage from the power supply unit even in the power saving state, and the signal transmission step is performed on the select signal line that is logic “1” in the image formable state. And a step of connecting a cassette open / close detection switch to / from which signal connection is made in response to opening / closing of the paper feed cassette .

  Further, the present invention can be provided as a program for causing a computer to circulate individually via a telecommunication line or the like. In this case, the central processing unit (CPU) realizes the control operation in cooperation with each circuit other than the CPU according to the program of the present invention. Each means realized by using the program and the CPU can also be configured by using dedicated hardware. The program can also be distributed in a state where it is recorded on a computer-readable recording medium such as a CD-ROM.

  According to the image forming apparatus and the cassette open / close detection method of the present invention, by effectively using the existing select signal line, the standby power in the power saving mode is reduced and the cassette open / close is detected without increasing the signal line. It becomes possible.

1 is a conceptual diagram illustrating an overall configuration inside a multifunction peripheral according to the present invention. It is a conceptual diagram which shows the whole structure of the operation part which concerns on this invention. It is a figure which shows the structure of the control system hardware of the multifunctional device which concerns on this invention. FIG. 2 is a functional block diagram of a multifunction machine according to an embodiment of the present invention. It is a flowchart for showing the execution procedure of the embodiment of the present invention. FIG. 2 is a conceptual diagram illustrating an internal structure of a multifunction peripheral and a paper feed cassette according to an embodiment of the present invention. FIG. 7A shows an example of the operation screen displayed on the touch panel of the present invention (FIG. 7A), and FIG. 7B shows an example of the paper feed cassette opening screen displayed on the touch panel of the present invention (FIG. 7B). ).

  Hereinafter, an image forming apparatus according to an embodiment of the present invention will be described with reference to the accompanying drawings for understanding of the present invention. In addition, the following embodiment is an example which actualized this invention, Comprising: The thing of the character which limits the technical scope of this invention is not. Moreover, the alphabet S added before the number in a flowchart means a step.

<Image forming apparatus>
Hereinafter, an image forming apparatus according to an embodiment of the present invention will be described. FIG. 1 is a schematic diagram of an image forming apparatus according to an embodiment of the present invention. However, details of each part not directly related to the present invention are omitted.

  The image forming apparatus of the present invention corresponds to, for example, a multi-function machine having functions such as a copy, a scanner, and a printer, and functions as an image forming apparatus having a copy function, a facsimile transmission / reception function, a scanner function, a printer function, and the like. To do.

  Hereinafter, for example, the operation of the MFP 100 (Multi Function Peripheral) when the user uses the copy function will be briefly described.

  First, when the user uses the multifunction machine 100, the document is placed on the document table 101 provided on the upper surface of the casing. Subsequently, the user uses the operation unit 102 (operation panel) provided in the vicinity of the platen 101 to input setting conditions relating to image formation from the initial screen (operation screen) of the operation unit 102. . When the user selects a copy function corresponding to image formation and presses a start key provided on the operation unit 102, the multifunction peripheral 100 starts the selected function.

  Here, in the image reading unit 103, the light emitted from the light source 104 is reflected by the document placed on the document table 101. The reflected light is guided to the image sensor 108 by the mirrors 105, 106, and 107. The guided light is photoelectrically converted by the image sensor 108, and image data corresponding to the original is generated.

  Here, a part for forming a toner image based on the image data is an image forming unit 109. The image forming unit 109 is provided with a photosensitive drum 110. The photosensitive drum 110 rotates in a predetermined direction at a constant speed, and around the charger drum 111, the exposure unit 112, the developing unit 113, the transfer unit 114, the cleaning unit 115, and the like in that order from the upstream side in the rotation direction. Is arranged.

  The charger 111 uniformly charges the surface of the photosensitive drum 110. The exposure unit 112 irradiates the charged surface of the photosensitive drum 110 with a laser based on the image data to form an electrostatic latent image. The developer 113 forms a toner image by attaching toner to the formed electrostatic latent image. The formed toner image is transferred to a recording medium (for example, paper, sheet) by the transfer device 114. The cleaning unit 115 removes excess toner left on the surface of the photosensitive drum 110. A series of these processes is executed by rotating the photosensitive drum 110.

  The sheets are conveyed from a plurality of paper feed cassettes 116 provided in the multi function peripheral 100. When the sheet is conveyed, the sheet is pulled out from any one of the sheet feeding cassettes 116 to the conveyance path by the pickup roller 117. Each sheet cassette 116 stores sheets of different paper types, and the sheets are fed based on setting conditions relating to image formation.

  The sheet pulled out to the conveyance path is fed between the photosensitive drum 110 and the transfer device 114 by the conveyance roller 118 and the registration roller 119. When the sheet is fed, the toner image is transferred to the sheet by the transfer unit 114 and conveyed to the fixing device 120.

  When the sheet on which the toner image is transferred passes between a heating roller and a pressure roller provided in the fixing device 120, heat and pressure are applied to the toner image, and the visible image is fixed on the sheet. The The amount of heat of the heating roller is optimally set according to the paper type, and the fixing is performed appropriately. The visible image is fixed on the sheet and the image formation is completed, and the sheet is discharged by a conveyance roller 118 to a cylinder tray 122 provided in the cylinder of the casing unit via a sheet discharge port 121. Is done. The sheets are stacked and stored on the in-body tray 122. By the above procedure, the housing unit of the multifunction peripheral 100 provides an image forming function to the user.

  FIG. 2 is a conceptual diagram showing the overall configuration of the operation unit according to the embodiment of the present invention. The user uses the operation unit 102 to input setting conditions for image formation as described above, and to confirm the input setting conditions. When the setting conditions are input, a touch panel 201 (operation panel), a touch pen 202, and operation keys 203 provided in the operation unit 102 are used.

  The touch panel 201 has both a function for inputting setting conditions and a function for displaying the setting conditions. That is, by pressing a key in the screen displayed on the touch panel 201, a setting condition corresponding to the pressed key is input.

  A display unit (not shown) such as an LCD (Liquid Crystal Display) is provided on the back surface of the touch panel 201, and the display unit displays an operation screen such as the initial screen, for example. A touch pen 202 is provided in the vicinity of the touch panel 201, and when the user brings the tip of the touch pen 202 into contact with the touch panel 201, the touch panel 201 detects the touch destination.

  Further, a predetermined number of operation keys 203 are provided in the vicinity of the touch panel 201, and for example, a ten key 204, a start key 205, a clear key 206, a stop key 207, a reset key 208, and a power key 209 are provided.

  Next, the configuration of the control system hardware of the multifunction peripheral 100 will be described with reference to FIG. FIG. 3 is a diagram showing the configuration of the control system hardware of the multifunction peripheral 100 according to the present invention. However, details of each part not directly related to the present invention are omitted.

  The control circuit of the MFP 100 includes a CPU (Central Processing Unit) 301, a ROM (Read Only Memory) 302, a RAM (Random Access Memory) 303, a HDD (Hard Disk Drive) 304, a driver 305 corresponding to each driving unit, and a touch panel. 201, operation keys 203, and an internal interface 306 are connected by an internal bus 307.

  The CPU 301 uses, for example, the RAM 303 as a work area, executes a program stored in the ROM 302, the HDD 304, and the like, and based on the execution result, from the driver 305, the touch panel 201, and the internal interface 306. The data, instructions, signals corresponding to the operation keys 203, commands, and the like are exchanged to control the operation of each drive unit shown in FIG.

  The internal interface 306 is communicably connected to the internal bus 309 of the paper feed cassette 126 via the internal interface 308 of the paper feed cassette 126. The internal bus 309 is connected to the CPU 310, the ROM 311, the RAM 312, the driving unit 313, and the sensor unit 314 of the control circuit of the sheet cassette 126. The CPU 301 of the multifunction peripheral 100 is connected to the CPU 310, the ROM 311 of the sheet cassette 126, It is configured to be able to communicate with the RAM 312, the drive unit 313, and the sensor unit 314.

  Also, each means (shown in FIG. 4) described later other than the drive unit is realized by the CPU 301 executing a program. The ROM 302, the HDD 304, and the like store programs and data for realizing each means described below.

<Embodiment of the present invention>
Next, the configuration and execution procedure according to the embodiment of the present invention will be described with reference to FIGS. 4 and 5. FIG. 4 is a functional block diagram of the multifunction machine of the present invention. FIG. 5 is a flowchart for showing the execution procedure of the present invention.

  First, when the user turns on the power of the multi-function device 100, the image forming unit 401 of the multi-function device 100 is activated (FIG. 5: S101), and shifts from a stopped state to a state where image formation is possible. Specifically, the image forming unit 401 starts power supply to the image reading unit 103 and the image forming unit 109 and starts power supply to a control circuit (CPU or the like) built in the paper feed cassette 116. . By supplying power to the CPU of the paper feed cassette 116, the paper feed unit 402 is activated to control a drive unit 313 related to driving of the pickup roller 117 and a sensor unit 314 that detects opening and closing of the paper feed cassette 116.

  Here, the image forming unit 401 and the sheet feeding unit 402 may have any configuration. For example, the following configuration can be adopted.

  That is, as shown in FIG. 6, in the multi-function device 100 according to the present invention, the CPU 301 provided in the main body of the multi-function device 100 and the CPU 310 provided for each paper feed unit 116 include a three-line select signal line. 600, 601, and 602 are connected. The CPU 301 of the multifunction peripheral 100 functions as the image forming unit 401, and the CPU 310 for each sheet feeding unit 116 functions as the sheet feeding unit 402.

  Three-line select signal lines 600, 601, 602 are control lines for designating a specific paper feed cassette 116, and are crossed between the paper feed cassettes 116 before the CPU 310 of each paper feed cassette 116. Connected to. By using the signal logic of these three select signal lines 600, 601, and 602 as a 3-bit address, a specific sheet cassette 116 can be specified.

  For example, in FIG. 6, three paper feed cassettes 116 are stacked in a stacked manner from top to bottom, and the three select signal lines 600, 601, and 602 are the second from the top paper feed cassette 116a from the top. When passing to the paper feed cassette 116b, the rightmost select signal line 602 intersects the leftmost side, the middle select signal line 601 intersects the rightmost side, and the leftmost select signal line 600 intersects the middle. Crossed on. When the three select signal lines 600, 601, and 602 pass from the second paper feed cassette 116b from the top to the third paper feed cassette 116c, the rightmost select signal line 601 is the leftmost. , The middle select signal line 600 intersects the rightmost side, and the leftmost select signal line 602 intersects the middle.

  On the other hand, the connection form of the CPU 310 in each paper feed cassette 116 to the three select signal lines 600, 601, and 602 is the same in any paper feed cassette 116, and the leftmost select signal line is the first from the top. The middle select signal line is connected to the second port, and the rightmost select signal line is connected to the third port. The CPU 310 of the paper feed cassette 116 has, for example, “1” (HIGH signal) at the first port from the top, “0” (LOW signal) at the second port, and “0” at the third port. When input, it is configured so that it is recognized that it has been designated (selected).

  Then, for example, the CPU 301 of the multi-function peripheral 100 sends a “1” signal to the leftmost select signal line 600, a “0” signal to the middle select signal line 601, and a rightmost select signal line 602. When a signal of “0” is transmitted, the CPU 310 of the first paper feed cassette 116a from the top to the CPU 310 of the first paper feed cassette 116a from the top in order from the top port by the intersection of the three select signal lines 600, 601 and 602. ”,“ 0 ”,“ 0 ”are input, and“ 0 ”,“ 1 ”,“ 0 ”are input to the CPU 310 of the second sheet cassette 116b in order from the top port from the top. “0”, “0”, and “1” are input to the CPU 310 of the second paper feed cassette 116c in order from the first port from the top. In this case, it is recognized that only the CPU 310 of the first paper feed cassette 116a from the top is designated, and the CPUs 310 of the other paper feed cassettes 116b and 116c are recognized as not designated. In other words, the CPU 301 of the multifunction peripheral 100 can specify a specific paper feed cassette 116 among the three paper feed cassettes 116 by changing the signal logic of the three select signal lines 600, 601, and 602. Become.

  For example, the CPU 301 of the multi-function peripheral 100 sends a “0” signal to the leftmost select signal line 600, a “1” signal to the middle select signal line 601, and a rightmost select signal line 602. When each “0” signal is transmitted, “1”, “0”, and “0” are input to the CPU 310 of the third paper feed cassette 116c from the top in order from the first port from the top. Therefore, in this case, the multifunction peripheral 100 designates the third paper feed cassette 116c. Others are the same.

  Here, the position before receiving the signals of the three select signal lines, specifically, the front position of the CPU 301 of the multifunction peripheral 100 and the front position of the CPU 310 of each paper feed cassette 116 are to ensure drivability. In addition, predetermined buffers 603 and 604 are provided to ensure signal transmission and reception.

  When the image forming unit 401 shifts to an image formable state, the image forming unit 401 displays an operation screen on the touch panel 201 and accepts a job such as image formation from the user.

  As shown in FIG. 7A, the operation screen 700 is shifted to a power saving mode, a predetermined message “Can copy” 701, a function item key 702 for inputting setting conditions such as a copy function, and the like. A power saving mode key 703 is displayed.

  When the user who has confirmed the operation screen 700 inputs a setting condition relating to image formation by, for example, operating the function item key 702 and presses the start key 205, the image forming unit 401 performs a print job under the setting condition. A toner image is formed based on the image data.

  Here, for example, when a sheet of a size corresponding to the sheet size of the setting condition is stored in the third sheet feeding cassette 116c from the top, the image forming unit 401 has three sheets as described above. Of the select signal lines 600, 601, and 602, a “0” signal is sent to the leftmost select signal line 600, a “1” signal is sent to the middle select signal line 601, and the rightmost select signal line 602 is sent. Each of the “0” signals is transmitted to designate the paper feeding means 402 of the third paper feeding cassette 116c. Receiving the designation, the paper feeding unit 402 drives the pickup roller 117 to pull out a predetermined sheet and conveys it to the main body of the multifunction peripheral 100. The image forming unit 401 forms an image of the toner image on the conveyed paper, executes printing, and discharges a printed matter corresponding to the toner image to the in-body tray 122. As a result, the print job is executed.

  In FIG. 6, each paper feed cassette 116 is closed when the paper feed cassette 116 is opened, and a predetermined signal line of the CPU 310 is electrically connected to the GND. When closed, a cassette open / close detection switch 605 is provided that is in an open state and releases the electrical connection of the signal line of the CPU 310 to GND.

  When the user opens a predetermined paper feed cassette 116 by the cassette open / close detection switch 605, the cassette open / close detection switch 605 of the paper feed cassette 116 is closed, and the CPU 310 (paper feed means 402) of the paper feed cassette 116 is closed. Detects the electrical connection of the signal line to the GND, and detects that the paper feed cassette 116 has been opened. On the other hand, when the user closes the paper feed cassette 116, the cassette open / close detection switch 605 of the paper feed cassette 116 is opened, and the CPU 310 of the paper feed cassette 116 connects the signal line to the GND. By detecting the release, it is detected that the paper feed cassette 116 is closed. Such opening / closing detection of the paper feed cassette 116 can be performed when power is supplied to the CPU 310.

  By the way, when the user presses the power saving mode key 703 while viewing the operation screen 600, or a predetermined power saving transition time (sleep time) has elapsed since the transition to the image formable state. In this case, the image forming unit 401 shifts from an image formable state to a power saving state (FIG. 5: S102 YES).

  In this case, since the image reading function and the image forming function are unnecessary, the power supply to the image reading unit 103 and the image forming unit 109 is stopped and the power supply to the CPU 310 of the paper feed cassette 116 is stopped (FIG. 5). : S103). As a result, the operation of the sheet feeding means 402 of each sheet cassette 116 is stopped, and power consumption is reduced.

  On the other hand, since a minimum function for receiving a facsimile reception job transmitted via a network or a print job transmitted from another terminal device is necessary, the image forming unit 401 sends the image forming unit 401 to the CPU 301 of the multifunction peripheral 100 main body. Will maintain the power supply.

  When the image forming unit 401 shifts to the power saving state, the signal receiving unit 403 is notified to that effect, and the signal receiving unit 403 having received the notification indicates that the main body of the multifunction peripheral 100 has the select signal lines 600, 601, A signal from the paper feed cassette 116 can be received via 602 (FIG. 5: S104).

  The signal receiving unit 403 may receive any signal from the paper feed cassette 116, and may be any method, for example, as follows.

  As shown in FIG. 6, a bidirectional signal switching function is provided in the buffer 603 at the front position of the CPU 301 of the multifunction peripheral 100. When the signal receiving unit 403 is ready to form an image, the buffer 603 is switched in one direction of the signal from the main body of the multi-function peripheral 100 to the paper feed cassette 116, and the CPU 301 of the multi-function peripheral 100 causes the CPU 301 to A signal can be transmitted to the CPU 310 of the paper cassette 116 via the select signal lines 600, 601, and 602. In this case, the reverse does not occur.

  On the other hand, when the signal receiving unit 403 is in the power saving state, the buffer 603 is switched to the other direction of the signal from the paper feed cassette 116 to the multifunction peripheral 100 main body, and the CPU 301 of the multifunction peripheral 100 causes the select signal to be changed. A signal from the sheet cassette 116 can be received via the lines 600, 601, and 602. In this case, the reverse does not occur.

  As a result, the MFP 100 main body can receive the signal transmitted from the paper feed cassette 116 even in the power saving state.

  Now, in the power saving state, the image forming unit 401 does not cancel the power saving state (FIG. 5: S105 NO), and the user can, for example, refill the paper cassette 116 or change the paper. When a specific paper feed cassette 116 (for example, the second paper feed cassette 116b from the top) is opened (FIG. 5: S106 YES), the signal transmission means 404 of the multifunction peripheral 100 corresponds to the open state of the paper feed cassette 116b. Then, a signal is transmitted from the paper feed cassette 116b to the MFP 100 main body via the select signal lines 600, 601, and 602 (FIG. 5: S107).

  Any method may be used for the signal transmission unit 404 to transmit a signal from the paper feed cassette 116b to the MFP 100 main body via the select signal lines 600, 601, and 602. It is made like.

  As shown in FIG. 6, a signal line 605 a connected to the signal line of the CPU 310 of the cassette opening / closing detection switch 605 of the paper feed cassette 116 is branched, and the branched signal line 605 b is buffered 604 at the front position of the CPU 310. And a single select signal line provided between the CPU 301 of the multifunction peripheral 100 and the buffer 603 at the front position. The select signal lines other than the select signal line to which the signal line 605b is connected are electrically connected to GND.

  Next, an output terminal of a power supply unit 606 that applies a predetermined voltage (for example, a control voltage of 3.3 V) to the select signal line to which the branched signal line 605b is connected even in a power saving state (power supply) is provided. Connect electrically.

  As a result, when the paper feed cassette 116 is opened, the cassette open / close detection switch 605 is closed, the current from the power supply unit 606 flows to the GND via the select signal line, and the signal receiving means 403 The signal flows to the main body of the multifunction peripheral 100 through the buffer 603 that enables the other direction of the signal. This flowing current functions as a signal, and a signal can be transmitted to the select signal line corresponding to the open state of the paper feed cassette 116.

  The signal transmission unit 404 transmits a signal from the paper feed cassette 116 to the MFP 100 main body via the select signal line, not via the CPU 310 of the paper feed cassette 116. Even in a power saving state in which power is not supplied to the CPU 310 of the paper cassette 116, the open state of the paper feeding cassette 116 can be detected by effectively using the select signal line.

  The signal line 605b is provided with a first resistor 605c having a predetermined resistance value (for example, 10 kΩ), and the power supply unit 606 has a position immediately before applying a voltage to the select signal line. A second resistor 606a having a resistance value (for example, 100 kΩ) that is several times (10 times) the resistance value of the first resistor 605c is provided. In this way, by providing a predetermined resistance to the select signal line, it is possible to reliably detect the level (“1” or “0”) of the signal passing through the select signal line.

  When the signal transmission unit 404 transmits a signal from the sheet feeding cassette 116 to the main body of the multi-function peripheral 100 through the select signal lines 600, 601, and 602, the open detection means 405 of the multi-function peripheral 100 causes the select signal line. Then, a signal from the paper feed cassette 116 is received (FIG. 5: S108), and it is detected that a specific paper feed cassette corresponding to the signal of the select signal line has been opened (FIG. 5: S109).

  Here, as shown in FIG. 6, since the three select signal lines 600, 601, and 602 are configured to intersect, for example, the signal transmission unit 404 is the first from the top in each paper feed cassette 116. The signal line 605b from the cassette open / close detection switch 605 is electrically connected to the select signal line, and a signal is transmitted to the first select signal line. Then, when the paper feeding cassette 116 is opened, a signal is transmitted to the leftmost select signal line 600 in the first paper feeding cassette 116a from the top, and the rightmost paper feeding cassette 116b transmits the signal on the rightmost side. A signal is transmitted to the select signal line 602, and in the third paper feed cassette 116c, a signal is transmitted to the middle select signal line 601. That is, the three select signal lines 600, 601, and 602 correspond to a specific sheet cassette 116, respectively.

  Thus, for example, if the user opens the second paper feed cassette 116b from the top, the paper feed cassette 116b transmits a signal to the rightmost select signal line 602. The detection unit 405 can detect that a specific paper feed cassette 116 has been opened in response to signals transmitted from predetermined select signal lines 600, 601, and 602.

  When the open detection unit 405 detects that the specific paper feed cassette 116 is in the open state, the image forming unit 401 notifies the image forming unit 401 to that effect, and the image forming unit 401 that has received the notification notifies the power saving state. The power supply to the image reading unit 103 and the image forming unit 109 is started, and the power supply to the CPU 310 of the paper feed cassette 116 is started to operate the paper feed unit 402 of the paper feed cassette 116 ( FIG. 5: S110). As a result, it is possible to detect the open state of the paper feed cassette 116 and shift to a state in which image formation is possible without supplying power to the CPU 310 of the paper feed cassette 116.

  When the image forming unit 401 cancels the power saving state, the signal receiving unit 403 is notified to that effect, and the signal receiving unit 403 that has received the notification indicates that the main body of the multifunction peripheral 100 has the select signal lines 600, 601, A signal can be transmitted via 602 (FIG. 5: S111). As a result, the MFP 100 main body can designate a specific sheet cassette 116 via the select signal lines 600, 601, and 602 as usual.

  The image forming unit 401 displays a paper feed cassette opening screen on the touch panel 201 in response to the open state of the paper feed cassette 116.

  As shown in FIG. 7A, the paper feed cassette open screen 704 displays a predetermined message “second stage paper feed cassette opened” 705 and the status of the paper feed cassette 116 in the open state. A status display “paper size A4, paper remaining amount 80%” 706 and an OK key 707 are displayed. Thus, the user can know the status of the opened paper feed cassette 116 by checking the paper feed cassette opening screen 704.

  The status of the paper feed cassette 116 can include, for example, paper presence / absence information, presence / absence of options, etc. in addition to the paper size and the remaining amount of paper.

  In S105, for example, when the MFP 100 accepts a facsimile reception job via a network, the image forming unit 401 of the MFP 100 cancels the power saving state (FIG. 5: S105 YES), and image reading is performed. Power supply to the section 103 and the image forming section 109 is started, and power supply to the CPU 310 of the paper feed cassette 116 is started (FIG. 5: S112). As a result, the sheet feeding means 402 of the sheet feeding cassette 116 also starts to operate.

  Next, when the image forming unit 401 cancels the power saving state, the signal receiving unit 403 enables the MFP 100 main body to transmit a signal via the select signal lines 600, 601, and 602 (FIG. 5: S111).

  In this case, for example, the image forming unit 401 forms a toner image based on the image data received by the facsimile, conveys the sheet by the paper feeding unit 402, and outputs a printed matter corresponding to the facsimile reception. become.

  As described above, according to the present invention, when the MFP 100 shifts to the power saving state, the MFP 100 main body can receive the signal from the sheet cassette 116 via the select signal line, and the predetermined sheet cassette. When 116 is opened, corresponding to the open state of the paper feed cassette 116, signal transmission means 404 for sending a signal from the paper feed cassette 116 to the MFP 100 main body via the select signal line, and the select signal And an open detection means 405 for detecting that a specific paper feed cassette 116 corresponding to the signal of the select signal line is opened when a signal from the paper feed cassette 116 is received via the line. .

  Accordingly, by effectively using the existing select signal line, it is possible to reduce standby power in the power saving mode and detect opening / closing of the cassette without increasing the number of signal lines. In addition, by using the select signal line, it is not necessary to provide a separate signal line for detecting the opening / closing of the cassette, and the number of signal lines generated between the main body and the paper feeding cassette and between each paper feeding cassette. Can be drastically reduced, which is also effective for cost reduction.

  In the embodiment of the present invention, the MFP 100 is configured to include each unit. However, a program that realizes each unit may be stored in a storage medium, and the storage medium may be provided. In this configuration, the multifunction device 100 reads the program, and the multifunction device 100 implements the respective units. In that case, the program itself read from the recording medium exhibits the effects of the present invention. Furthermore, it is possible to provide a method for storing the steps executed by each means in a hard disk.

  As described above, the image forming apparatus and the cassette open / close detection method according to the present invention are useful not only for multifunction peripherals but also for copying machines, printers, image forming apparatuses, and the like, and by effectively using existing select signal lines, This is effective as an image forming apparatus and a cassette open / close detection method capable of reducing standby power in the power saving mode and detecting cassette open / close without increasing the number of signal lines.

DESCRIPTION OF SYMBOLS 100 MFP 102 Operation part 401 Image formation means 402 Paper feed means 403 Signal reception means 404 Signal transmission means 405 Open detection means

Claims (3)

Communicatively connected via a plurality of sheet feeding cassettes and a plurality of select signal line, the process proceeds to the power saving state to stop the power supply to the sheet feeding cassettes, an image forming apparatus that maintains the power supply to the body Because
After shifting to the power saving state, and the signal receiving means own apparatus main body and can receive a signal from the paper feed cassette via said select signal line,
When a predetermined of said paper feed cassette is opened, a signal transmitting means in response to an open state of the sheet feeding cassette, a signal is transmitted from the sheet feeding cassette to the own apparatus main body via a plurality of select signal lines,
Upon receiving a signal from said plurality of paper feeding cassettes via the plurality of select signal lines, and an open detection means for detecting a particular said sheet cassette corresponding to the signal is in the open state,
The plurality of select signal lines are logical ones of the plurality of select signal lines when the apparatus body designates a specific paper feed cassette among the plurality of paper feed cassettes in an image formable state. “1”, others are set to logic “0”, and any one of the sheet feeding cassettes to which the select signal line of logic “1” is designated are wired so as to have the same port position,
The signal transmitting means is
A signal line that connects a cassette open / close detection switch that is electrically connected to and detached from the select signal line that is logical “1” in response to the open / close of the paper feed cassette, in the image forming enable state;
An image forming apparatus comprising: a power supply unit that applies a predetermined voltage to a select signal line electrically connected to the signal line even in a power saving state . In the buffer provided on the select signal line between the main unit and the paper cassette, a bidirectional signal switching function is provided.
In the power saving state, the signal receiving unit switches the buffer in one direction of a signal from the sheet cassette to the apparatus main body, and the apparatus main body supplies the sheet cassette through the select signal line. The image forming apparatus according to claim 1, wherein a signal from the image forming apparatus can be received. Communicatively connected via a plurality of sheet feeding cassettes and a plurality of select signal line, the process proceeds to the power saving state to stop the power supply to the sheet feeding cassettes, an image forming apparatus to maintain the power supply to the body The cassette open / close detection method of
After shifting to the power saving state, a step that allows receiving the signal from the paper feed cassette own apparatus main body via a plurality of select signal lines,
When a predetermined of said paper feed cassette is opened, a step corresponding to the open state of the sheet feeding cassette, and transmits the signal via the plurality of select signal lines from the sheet feeding cassette to the own apparatus main body,
Detecting signals from the plurality of sheet cassettes via the plurality of select signal lines that the specific sheet cassette corresponding to the signals has been opened; and
The plurality of select signal lines are logical ones of the plurality of select signal lines when the apparatus body designates a specific paper feed cassette among the plurality of paper feed cassettes in an image formable state. In any of the paper feed cassettes in which “1” is set, the others are set to logic “0”, and the select signal line of the logic “1” is designated, they are wired so as to have the same port position. The select signal line electrically connected to the line is wired so as to apply a predetermined voltage from the power supply unit even in the power saving state.
The signal transmission step comprises:
Connecting a cassette open / close detection switch that is electrically connected to and detached from the select signal line that is logic “1” in response to the opening / closing of the paper feed cassette to the signal line in the image forming enable state. A cassette open / close detection method characterized by the above.

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