JP2007091442A - Image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To lower power consumption of a drive system as well as a sensor, and efficiently lower the power consumption according to printing request and a state of a paper feeding means, in a paper-feed unit. <P>SOLUTION: An image forming device comprises a printing means (image forming part) for printing an image; the paper feeding means (paper-feed unit) for feeding paper to the printing means; a power supply means (power supply part 30) for supplying electrical power to respective parts of a printer 1; and an interruption switching means (interruption switching control part of a main control part 100) for performing, independently with respect to various operation control parts, switching between interruption and non-interruption of the power supply from the power supply means to the respective operation control parts of the paper feeding means including conveyance control parts 403, 503, 603, and 703 for controlling paper conveyance operation, sensor control parts 404, 504, 604, and 704 for controlling operation of various sensors, and a lift control parts 405, 505, 605, and 705 for controlling paper lifting and lowering operation. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image forming apparatus such as a printer or a copying machine, and more particularly to an image forming apparatus having a function of reducing power consumption in power supply to a paper feeding unit.

In recent years, miniaturization and energy saving of various devices have progressed, and accordingly, low power consumption of devices has been strongly demanded. In this regard, in an image forming apparatus such as a printer or a copying machine, for example, Patent Document 1 discloses that power supply for a sensor is cut off by changing a setting of a supply current value for a sensor (photosensor) of each part of the apparatus. A technique for reducing the above is disclosed.
JP 2000-278469 A

  By the way, in order to reduce the power consumption of the image forming apparatus, not only the above-mentioned sensor but also a drive system such as a drive motor (carrying motor) for paper conveyance with higher power consumption and a lift drive unit for moving up and down the paper. (In this case, a sheet feeding unit including the transport motor and the lift driving unit in the image forming apparatus is considered). However, the above prior art is specialized for sensors, and these drive systems are not disclosed. In general, the sensor and the drive system in the image forming apparatus are configured such that power is always supplied during printing and standby for printing.

  The present invention has been made in view of the above circumstances, and in the paper feed unit, not only the sensor but also the drive system with higher power consumption can reduce power consumption, print requests, and the state of the paper feed unit. An object of the present invention is to provide an image forming apparatus capable of efficiently reducing power consumption according to the above.

  An image forming apparatus according to a first aspect of the present invention includes a printing unit that prints an image, a sheet feeding unit that feeds paper to the printing unit, a power supply unit that supplies power to each unit of the apparatus, and the sheet feeding Power from the power supply means for each operation control unit including a conveyance control unit that controls the conveyance operation of the sheet, a sensor control unit that controls the operation of various sensors, and a lift control unit that controls the lifting and lowering operation of the sheet. It is characterized by comprising a cutoff switching means for switching the supply cutoff and non-cutoff independently for each operation control section.

  According to the above configuration, the printing unit prints an image, the sheet feeding unit feeds the image to the printing unit, and the power supply unit supplies power to each unit. In addition, each operation control including a conveyance control unit that controls the conveyance operation of the paper in the paper supply unit, a sensor control unit that controls the operation of various sensors, and a lift control unit that controls the lifting and lowering operation of the paper by the shut-off switching unit. Switching of power supply from the power supply means to the part is switched independently for each operation control part.

  Further, in the above configuration, the paper feeding unit includes a plurality of paper feeding units, and the shut-off switching unit is configured to operate each operation control unit of the paper feeding unit in which a type of paper different from a print request is set during a printing operation. It is preferable to partially cut off the power supply to the operation control unit that is not required by the print request of each operation control unit.

  In the above configuration, the plurality of paper feeding units are configured in a plurality of stages, and a paper feeding unit in which a type of paper that meets the print request in the plurality of paper feeding units is set as a paper feeding unit A. If the paper feed unit on which a paper of a type different from the print request is set is a paper feed unit B, the shut-off switching unit is configured to use the paper feed unit B when the paper feed unit B is arranged on the lower side of the paper feed unit A. It is preferable to cut off the power supply to the conveyance control unit of the paper feeding unit B that does not require the conveyance operation.

  In the above configuration, the shut-off switching unit further cuts off the power supply to the sensor control unit of the paper feed unit B when the paper feed unit B is arranged on the lower side of the paper feed unit A. Is preferred.

  In the above configuration, when the sensor control unit of the paper feed unit A detects that there is no paper in the paper feed unit A, the shut-off switching unit is connected to the lift control unit of the paper feed unit A. It is preferable to cut off the power supply.

  In the above configuration, when the sensor control unit detects that there is no sheet in the sheet feeding unit A, the display unit displays information for prompting the user to feed the sheet to the sheet feeding unit A. It is preferable to further comprise.

  In the above configuration, it is preferable that the shut-off switching unit shuts off power supply to the sensor control unit or the lift control unit of the paper feed unit on which a paper of a different type from the print request is set during a printing operation. .

  Further, in the above-described configuration, the sensor control unit is configured to cause the shut-off switching unit to switch to the non-blocking at a predetermined timing before the end of the printing operation with respect to the paper feeding unit in which power supply to the sensor control unit is cut off. It is preferable to further include return control means for performing a return operation for causing the sensor control unit to detect the state of the paper feed unit while supplying power to the printer.

  Further, in the above-described configuration, the lift control unit is configured to cause the shut-off switching unit to switch to the non-blocking at a predetermined timing before the end of the printing operation with respect to the paper feeding unit in which power supply to the lift control unit is cut off. It is preferable to further include a return control means for performing a return operation for causing the lift control unit to perform the lifting and lowering operation of the sheet while supplying power to the.

  According to the first aspect of the present invention, the sheet feeding means includes a conveyance control unit that controls the conveyance operation of the sheet, a sensor control unit that controls the operation of various sensors, and a lift control unit that controls the movement of the sheet. Switching between power supply interruption and non-interruption for each operation control unit is performed independently for each operation control unit, so that not only a sensor but also a drive system that performs a paper conveyance operation and a lifting operation with higher power consumption The power supply can be cut off to reduce power consumption, and depending on the print request (print information such as print paper size and number of prints) and the state of the paper feed means (paper feed unit) It is possible to efficiently reduce power consumption by switching between power supply interruption and non-interruption for each operation control unit.

  According to the second aspect of the present invention, an operation that does not require power supply to each operation control unit of the paper feed unit in which a paper of a different type from the print request is set is not required by the print request of each operation control unit during the printing operation. Since it is partially cut off from the control unit (power supply to the operation control unit that is not required by the print request among the operation control units is cut off), it is necessary for each operation control unit during the printing operation. It is unnecessary even if it is printing while maintaining the power supply to the device (for example, the operation control unit that wants to start the operation immediately in response to this job without waiting time when the next print job occurs) For a product, the power supply is cut off, so that both power saving and operation responsiveness can be achieved and power consumption can be reduced efficiently.

  According to the third aspect of the present invention, when the paper feed unit B on which a type of paper different from the print request is set is arranged on the lower side of the paper feed unit A on which the type of paper meeting the print request is set. In addition, since the power supply to the transport control unit of the paper feeding unit B that does not require the paper transport operation is interrupted, a paper of a different type from the print request, that is, a paper that is not used for printing is set and the paper transport operation It is possible to reduce the power consumption of the conveyance control unit in the paper feeding unit B that does not require.

  According to the fourth aspect of the present invention, when the paper feeding unit B is arranged on the lower side of the paper feeding unit A, the power supply to the sensor control unit of the paper feeding unit B is further cut off. Paper consumption of the sensor control unit (for example, a conveyance sensor) is reduced together with the conveyance control unit in the paper feeding unit B in which a different type of paper, that is, a sheet that is not used for printing is set and the sheet conveyance operation is unnecessary. Can do.

  According to the fifth aspect of the present invention, when the sensor control unit detects that there is no paper in the paper supply unit A, the power supply to the lift control unit of the paper supply unit A is cut off. The power consumption of the lift control unit can be reduced without wastefully supplying power to the lift control unit of the paper feed unit that does not exist.

  According to the sixth aspect of the present invention, when there is no paper in the paper feeding unit A, information prompting the user to feed the paper is displayed on the display means. It is possible to visually recognize that the paper has run out, and it is possible to reliably perform replenishment (paper feeding) of paper to the paper feeding unit that has run out of paper.

  According to the seventh aspect of the present invention, the power supply to the sensor control unit or the lift control unit of the paper feeding unit on which a paper of a type different from the print request is set is interrupted during the printing operation. The power consumption of the sensor control unit (for example, the paper sensor) or the lift control unit in the paper feeding unit on which the paper, that is, the paper not used for printing is set can be reduced.

  According to the eighth aspect of the present invention, with respect to the paper feed unit in which the power supply to the sensor control unit is cut off, the sensor control unit is supplied to the sensor control unit at a predetermined timing (for example, immediately before the printing operation is completed) before the printing operation is completed. Since power supply is performed and the sensor control unit performs a return operation to detect the state of the paper feed unit, it prepares for the next print job, that is, responds to the next print job while reducing power consumption. Therefore, it is possible to maintain the operation responsiveness for quickly starting the operation.

  According to the ninth aspect of the present invention, with respect to the paper feed unit in which the power supply to the lift control unit is cut off, the lift control unit is supplied to the lift control unit at a predetermined timing before the printing operation ends (for example, immediately before the printing operation ends). When power is supplied and the lift control unit lifts and lowers the paper, for example, a return operation is performed in which the lift tray that has been lowered is moved up to a position where the paper can be taken out. As shown, the operation responsiveness for preparing for the next print job, that is, for quickly starting the operation in response to the next print job can be maintained.

  Hereinafter, an image forming apparatus according to the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view schematically showing an internal configuration of a printer 1 as an example of an image forming apparatus according to the present invention. The printer 1 includes a printer main body 10 and first to third paper feeding units 5 to 7 disposed below the printer main body 10. The printer main body 10 includes an image forming unit 2, a power supply unit 3, and a paper feeding unit 4. The image forming unit 2 forms (prints) a monochrome image on a sheet. The image forming unit 2 includes a photosensitive drum 201, a charging unit 202 disposed around the photosensitive drum 201, an exposure unit 203, a developing unit 204, and a cleaning unit. And a fixing unit 207 disposed on the downstream side of the photosensitive drum 201.

  The photoconductor drum 201 is a photoconductor (image carrier) made of, for example, amorphous silicon and configured to be rotatable in the arrow direction shown in FIG. The charging unit 202 uniformly charges the surface of the photosensitive drum 201 to a predetermined potential. The exposure unit 203 is a so-called laser scanning unit. The exposure unit 203 irradiates the surface of the photosensitive drum 201 with a laser beam (LED light) generated based on image data transmitted from an image memory or the like which will be described later. Forming an electrostatic latent image. The developing unit 204 exposes the electrostatic latent image as a toner image by attaching the toner supplied from the toner supply unit 2041 included in the developing unit 204 to the electrostatic latent image formed on the photosensitive drum 201. It is to make it.

  The cleaning unit 205 cleans the toner remaining on the surface of the photosensitive drum 201 after toner transfer by the transfer unit 206 described later is completed. The transfer unit 206 includes a transfer roller 2061, and is manifested on the photoconductive drum 201 in a state where the transfer roller 2061 is pressed against the photoconductive drum 201 through a sheet conveyed by the paper supply unit 4 described later. The transferred toner image is transferred onto the paper. The fixing unit 207 fixes the toner image transferred to the paper. The fixing unit 207 includes a heat roller 2071 and a pressure roller 2072, melts the toner on the paper by the heat of the heat roller 2071, and applies pressure by the pressure roller 2072 to fix the toner image on the paper. Note that the sheet subjected to the fixing process by the fixing unit 207 is conveyed to the discharge tray 211 on the upper part of the printer main body 10 by the conveyance roller 209 and the discharge roller 210 through the conveyance path 208.

  The power supply unit 3 (power supply unit) is a power supply for supplying power to each unit of the printer 1. The paper feed unit 4 is disposed below the printer body 10 and feeds the image forming unit 2. The sheet feeding unit 4 includes a sheet feeding cassette 41, a lift driving unit 42, a pickup roller 43, a conveyance path 44, a conveyance roller 45, a branch guide 46, a sheet sensor 47, a cassette sensor 48, and a conveyance sensor 49. The paper feed cassette 41 is a so-called standard paper feed cassette for the printer 1 for storing paper of a predetermined size (here, a general-purpose A4 size), and is configured to be detachable from the printer main body 10. Has been. The lift drive unit 42 moves the lift tray 411 included in the paper feed cassette 41 up and down, for example, in the vertical direction indicated by the arrow in the drawing, thereby moving the paper placed on the lift tray 411 up and down. . The pickup roller 43 is for taking out the paper stored in the paper feed cassette 41. The conveyance path 44 feeds the sheet taken out from the sheet feeding cassette 41 or the sheet conveyed from the first to third sheet feeding units 5 to 7 to the nip between the image forming unit 2 (the photosensitive drum 201 and the transfer roller 2061). Part). The conveyance roller 45 conveys the paper in the conveyance path 44. The branch guide 46 switches the transport route between the paper from the paper feed cassette 41 and the paper from the first to third paper feed units 5 to 7 according to the paper transport timing.

  The paper sensor 47 is composed of, for example, a photo sensor, and detects the remaining amount or presence of paper stored in the paper feed cassette 41, or the size and orientation of the paper. The cassette sensor 48 detects the presence or absence of the paper feed cassette 41 (whether or not the paper feed cassette 41 is attached to the printer main body 10). The conveyance sensor 49 detects whether or not a sheet is suitably conveyed in the conveyance path 44, in other words, whether or not a conveyance jam (paper jam) has occurred. Note that the sheet feeding unit 4 having such a configuration is hereinafter referred to as a standard sheet feeding unit 4.

  The first to third sheet feeding units 5 to 7 are sheet feeding units provided as so-called options with respect to the standard sheet feeding unit 4, and feed sheets to the image forming unit 2. The first to third sheet feeding units 5 to 7 are configured in a plurality of stages (a state in which they are stacked in the vertical direction as shown in FIG. 1) together with the standard sheet feeding unit 4. Sheets of a predetermined size are stored in each stage of the sheet feeding unit, specifically, a sheet feeding cassette provided in the sheet feeding unit. Here, for example, B5 size, A4 size (this is the same size as the paper size of the standard paper feed unit 4) and A3 size paper are stored in the first to third paper feed units 5 to 7, respectively. The first to third paper feeding units 5 to 7 are respectively the same as the standard paper feeding unit 4, the paper feeding cassettes 51, 61, 71, lift trays 511, 611, 711, lift driving units 52, 62, 72, pickup rollers 53, 63, 73, transport paths 54, 64, 74, transport rollers 55, 65, 75, branch guides 56, 66, 76, paper sensors 57, 67, 77, cassette sensors 58, 68, 78, and transport sensor 59 69, 79, and paper is fed from a predetermined paper feed unit in response to a print request.

  In the first paper feeding unit 5, as with the standard paper feeding unit 4, the lift tray 511 is moved up and down together with the paper by the lift driving unit 52, and the paper stored in the paper feeding cassette 51 is taken out by the pickup roller 53. The paper is transported in the transport path 54 by the transport roller 55, the paper transported from the paper feed cassette 51 by the branch guide 56, and the paper transported from the paper feed cassettes 61 and 71 below the paper feed cassette 51. The sheet sensor 57 detects the remaining amount and presence or absence of the sheet stored in the sheet feeding cassette 51 or the size of the sheet, and the cassette sensor 58 detects the presence or absence of the sheet feeding cassette 51. The presence or absence of a conveyance jam is detected by the conveyance sensor 59. The same applies to the second and third paper feeding units 6 and 7, and a description thereof will be omitted. Here, the sheet feeding unit includes the standard sheet feeding unit 4 and has a total of four stages. However, the sheet feeding unit may be configured with more or fewer stages. Further, the size of the paper stored in each paper supply unit is not limited to this, and for example, it is possible to use paper of different sizes.

  FIG. 2 is an outline view schematically showing the printer 1. For convenience in the following description of the operation of each paper feed unit, the standard paper feed unit 4 and the first to third paper feed units 5 to 5 in the printer 1 are shown. 7 is specified. As shown in the figure, the printer 1 is provided with a display unit 90, which will be described later, on the front unit or the like.

  By the way, in the standard paper feed unit 4 and the first to third paper feed units 5 to 7 of the printer 1, the following three controls are roughly divided. That is, (1) control for transporting paper (referred to as transport control), (2) control for detecting the state of the paper feed unit such as paper size or the remaining amount of paper or the presence or absence of paper (referred to as sensor control), and (3) remaining paper This is control for moving the paper up and down according to the amount and presence (called lift control). These three operation controls are not always necessary in the standard paper feed unit 4 and the first to third paper feed units 5 to 7, and when the printer 1 is in a standby state or during a printing operation (printing). Regardless of the print request, there is a control that is unnecessary for some or all of the paper feed units. Therefore, it is possible to reduce power consumption by efficiently executing these three controls. This will be described in detail below.

  FIG. 3 is a block diagram showing an example of an electrical configuration mainly related to three operation controls of the paper feeding unit in the printer 1. As shown in FIG. 3, the printer 1 includes a power supply unit 30, paper feed unit control units 40, 50, 60, 70, an input unit 80, a display unit 90, and a main control unit 100. The power supply unit 30 includes the power supply unit 3 and supplies power to an operation control unit described later in the sheet feeding unit control units 40 to 70, specifically, to branch units 401, 501, 601, and 701 described later. Supply.

  The input unit 80 includes a network I / F (interface) that controls transmission / reception of various data to / from an external device (information processing device) such as a PC connected via a network such as a LAN. Image data transmitted from the printer, or instruction information (command) input by an operation of the user in an external device, for example, print execution instruction information, or print setting information such as paper size and number of copies (number of copies) to the printer 1 Input. The input unit 80 is an operation unit for inputting an operation instruction by the user in the printer 1 (for example, various kinds of operations for inputting a print execution instruction or print setting information such as a paper size and the number of copies). An operation button may be provided).

  The display unit 90 displays various information such as information related to the printing operation and setting information. In response to an instruction from the display control unit 105, which will be described later, the display unit 90 displays a message such as “paper is out. Please feed paper” to notify the user that paper feeding is necessary ( Prompt the user to feed).

  The main control unit 100 (arithmetic processing unit) includes a ROM (Read Only Memory) that stores various control programs, a RAM (Random Access Memory) that temporarily stores data and functions as a work area, the control program, and the like. It consists of a CPU (Central Processing Unit) or the like that is read from the ROM and executed, and transmits / receives various control signals to / from each part of the printer 1 to control operation of the entire printer 1. Here, in particular, the main control unit 100 controls switching of power supply to each operation control unit by controlling the cutoff switching units 402, 502, 602, and 702 described later.

  The main control unit 100 includes an image forming unit 2 in addition to the above-described units, and a recording unit (illustrated) that performs image printing (recording) on a sheet based on image data stored in an image memory described later. And an image memory (not shown) for temporarily storing image data transmitted from an external device via the network I / F. In FIG. 3, for convenience of explanation, the paper feed unit control unit 40 and the printer main body 10 are illustrated separately, but the paper feed unit control unit 40 is actually included in the printer main body 10.

  The paper feed unit controllers 40, 50, 60, and 70 are disposed in the standard paper feed unit 4 and the first to third paper feed units 5 to 7, respectively, and carry control and sensor control in each paper feed unit. And lift control. The paper feed unit control units 40, 50, 60, and 70 are branch units 401, 501, 601, and 701, block switching units 402, 502, 602, and 702, conveyance control units 403, 503, 603, and 703, and a sensor control unit, respectively. 404, 504, 604, 704 and lift control units 405, 505, 605, 705 are provided. Here, since each unit has the same function, for example, the standard sheet feeding unit 4 will be described.

  The branching unit 401 connects the power supply path from the power supply unit 30 to the control units of the transport control unit 403, the sensor control unit 404, and the lift control unit 405 (hereinafter, these control units are referred to as operation control units). It branches to a plurality of corresponding power supply paths. The cut-off switching unit 402 performs on / off switching of power supply to each operation control unit (performs power supply to each operation control unit or cuts off power supply). It is a so-called change-over switch provided in each branched power supply path. However, this switch can be switched on and off mechanically or electrically.

  The conveyance control unit 403 controls the sheet conveyance operation by controlling the driving of the conveyance roller 45, the pickup roller 43, the branch guide 46 (collectively referred to as the conveyance unit), the drive motor, and the like. is there. The sensor control unit 404 controls sensor operations such as a paper sensor 47, a cassette sensor 48, and a transport sensor 49 (collectively referred to as a sensor unit). The lift control unit 405 controls the lift operation of the lift drive unit 42 (this is referred to as a lift unit). However, each operation control unit controls its operation while supplying power from the power supply unit 30 to each control target unit via the operation control unit.

  Here, as shown in FIG. 3, the sensor control unit 404 is provided with one power supply path, but actually, the paper sensor 47, the cassette sensor 48, and the conveyance are used according to the application of the sensor. Each sensor 49 has a power supply path, and the cutoff switching unit 402 can switch power supply to the sensor on and off for each application. Information detected by the sensor units (paper sensor, conveyance sensor, and cassette sensor) of each paper feeding unit is input to the main control unit 100 via each sensor control unit.

  The power from the power supply unit 30 is transmitted to the branching unit 401, and the main control unit 100 controls the on / off switching in the cutoff switching unit 402, thereby switching between energization and non-energization of each operation control unit. Is called.

  As described above, in the printer 1, the control systems (wiring lines) for switching on and off the power supply to the various operation control units of the transport control unit, the sensor control unit, and the lift control unit are separated (divided) from each other ( Thus, on / off switching of power supply to each operation control unit can be performed independently for each operation control unit.

  FIG. 4 is a functional block diagram mainly relating to power supply switching of the main control unit 100. The main control unit 100 includes a state detection unit 101, a cutoff switching control unit 102, a print information setting unit 103, a print control unit 104, and a display control unit 105. The state detection unit 101 detects the state of each unit of the printer 1 based on detection information from each sensor unit (paper sensor, conveyance sensor, and cassette sensor). For example, the state detection unit 101 is set based on detection information from the sheet sensor 47 (57, 67, 77), that is, the state of the standard sheet feeding unit 4 (first to third sheet feeding units 5 to 7). It detects the size and orientation of the current paper, the remaining amount of paper, the presence or absence of paper, etc. (acquires information on each state). Further, for example, based on detection information from the transport sensor 49 (59, 69, 79), the presence / absence of occurrence of a transport jam is detected, and based on detection information from the cassette sensor 48 (58, 68, 78), It detects whether or not the paper cassette 41 (51, 61, 71) is attached / detached, that is, whether or not each paper cassette has been attached / detached (for example, pulled out or pushed into a fixed position), or whether or not there is a paper cassette.

  Based on the state detection information detected by the state detection unit 101 and print information (print request) set in the print information setting unit 103 described later, the cutoff switching control unit 102 includes a transport control unit in each paper feed unit, Switching operation of power supply interruption / non-interruption for each operation control unit such as a sensor control unit and a lift control unit (conveying unit, sensor unit and lift unit) is independently controlled for each operation control unit. .

  The print information setting unit 103 sets a print request transmitted from the external apparatus to the printer 1, that is, print information (print instruction information) such as the size of the paper used for printing and the number of prints. is there. Also, the print information setting unit 103 determines which level of the print information based on the set print information and the status detection information by the status detection unit 101 (for example, the paper size and the presence / absence information of the paper for each of the paper feed units). It has a function of determining (selecting) whether to use a paper feed unit (corresponding to the second paper feed unit 6 in FIG. 5 described later). Note that the print information or the print request itself may include designation information of the paper feed unit to be used.

  The print control unit 104 controls the printing operation (image forming operation) for the image forming unit 2 based on the print information set in the print information setting unit 103. The display control unit 105 controls the display operation of various types of information on the display unit 90. For example, when the state detection unit 101 detects that there is no paper in a certain paper feed unit, the display control unit 105 displays this detection information. In response, the display unit 90 is controlled to display a message for prompting paper replenishment (paper feeding).

  Here, switching of power supply to each of the operation control units will be described with a specific example. FIG. 5 is a diagram for explaining an example of the power supply state of each part of the paper feed unit at the time of printing. On the right side of the figure, the power supply of the transport unit, sensor unit, and lift part in each paper feed unit is shown. ON (ON; non-blocking, energization), OFF (OFF; blocking, non-energization) states are shown. It is assumed that A4 size paper (A4 paper) is set in the standard paper supply unit 4, and B5 paper, A4 paper, and A3 paper are set in the first to third paper supply units 5 to 7, respectively.

  For example, assume that a job for printing 100 sheets of A4 size images using A4 paper of the second paper feed unit 6 occurs. In this case, the sheet conveyance control is required for the second sheet feeding unit 6 and the first sheet feeding unit 5 and the standard sheet feeding unit 4 that are arranged in the upper stage and through which the sheet passes. Since the conveyance control of the third sheet feeding unit 7 through which the sheet does not pass is unnecessary, the power supply to the conveyance unit (conveyance control unit 703) of the third sheet feeding unit 7 is turned off.

  Regarding the sensor unit (sensor control unit), it is necessary to detect the state of the paper feed unit (the remaining amount of paper, the presence or absence of paper, or the paper size), and the second paper feed unit 6 and the second paper feed unit. 6 is a standard paper feed unit 4 in which A4 paper of the same type, here the same size, is set. In other words, this corresponds to a paper feed unit in which A4 paper that matches the conditions of the print request is set. The power supply to the “paper sensor” of the first paper feed unit 5 and the third paper feed unit 7 on which paper other than the A4 paper is set is turned off. Regarding the “conveyance sensor”, the sheet feeding unit that requires the sheet feeding control, that is, the second sheet feeding unit 6, and the first sheet feeding unit 5 and the standard sheet feeding unit 4 arranged at the upper stage thereof are used. The power supply is turned on, and the power supply to the other third paper feed units 7 is turned off. As for the “cassette sensor”, the power supply is turned on for all paper feed units as in the standby mode described later.

  Regarding the lift unit (lift control unit), since it is necessary to maintain control in preparation for the next print job, the power supply is turned on for all the paper feed units. When the paper runs out during printing, the lift control of the paper feed unit is unnecessary, so when the paper runs out, the lift tray is lowered (lowered to the bottom of the paper feed cassette) The power supply to the lift unit (lift control unit) is turned off.

  Next, the case of standby will be described. FIG. 6 is a diagram for explaining the power supply state of each part of the sheet feeding unit during standby. In this case, since the control for transporting the paper is unnecessary, the power supply to the transport units (transport control units) of all the paper feeding units is turned off. As for the sensor unit (sensor control unit), the power supply is turned off except for the “cassette sensor” that detects attachment / detachment of the paper feed cassette. Regarding the lift unit (lift control unit), if the lift control is performed after the print job is generated, it takes time until the start of printing, which causes the user to wait, so it is necessary to maintain the lift control. Therefore, all the power supply to the lift part is turned on. Note that the paper supply unit that has run out of paper lowers the lift tray and turns off the power supply to the lift unit (lift control unit).

  As described above, the power supply is turned on for all of the transport unit (transport control unit), the sensor unit (sensor control unit), and the lift unit (lift control unit) at the time of printing or standby. In the present invention, since the power supply is partially turned off as appropriate in accordance with the print request or the state of the paper feed unit, the power consumption can be reduced accordingly.

  FIG. 7 is a flowchart illustrating an example of the power supply operation of the printer 1 according to the present embodiment. Printing is performed when the printer 1 is in a standby state, that is, the conveyance unit is OFF (power supply is OFF), the paper sensor and the conveyance sensor are OFF, and the cassette sensor is ON (power supply is ON) (step S1). When a job is generated, that is, when a print request from an external device or the like is received and print information is set in the print information setting unit 103 (step S2), all the paper sensors that have been turned off in the standby state are turned on. (Step S3). Next, the paper supply unit to be used by the print information setting unit 103 based on the print information (print request) and the status detection information by the status detection unit 101 (detection information of the paper sensor turned on in step S3). For example, the second paper feed unit 6 shown in FIG. 5 is determined (step S4). Then, the conveyance section (conveyance roller 65, pickup roller 63, branch guide 66; conveyance control section 603) of the second paper feed unit 6 determined in step S4 is turned on (step S5).

  Next, the status detection unit 101 detects the status of the other paper feed units, that is, the paper feed units other than the second paper feed unit 6 (step S6). In each paper feed unit in which the state is detected, a paper feed unit in which the same paper size (A4 paper) as the print request is set (stored) exists in the lower stage (lower stage side) (in this case, the standard paper feed) For the unit 4 and the second sheet feeding unit (YES in step S7), the conveyance unit of the sheet feeding unit is turned on (step S8), and the conveyance sensor is also turned on (step S9). In other words, the transport unit and the transport sensor of the paper feed unit (the third paper feed unit 7 in FIG. 5) that does not have the same paper size as the print request in the lower stage (lower stage side) are turned off. Further, the paper sensor of the paper feed unit (the first paper feed unit 5 and the third paper feed unit 7 in FIG. 5) having a paper size different from the print request is turned off. Further, the paper sensor of the paper feed unit (the first paper feed unit 5 and the third paper feed unit 7 in FIG. 5) in which paper of a size different from the print request is set is turned off (step S10). In step S7, if the lower sheet does not have the same paper size as the print request (NO in step S7), the process proceeds to the following step S11.

  Next, a printing operation is started in the power supply state (step S11). During execution of the print job (NO in step S12), if the state detection unit 101 (paper sensor 67) detects that there is no remaining paper in the second paper feed unit 6 that is currently using paper (step S12). In step S13, the lift unit (lift drive unit 62; lift control unit 605) of the second paper feed unit 6 is turned off (step S14), and the display control unit 105 prompts the user to replenish the paper (the paper has run out). Message) is displayed on the display unit 90 (step S15). When the user replenishes (feeds) paper to the second paper feed unit 6, the state detection unit 101 (paper sensor 67) detects that the paper is present (replenished) (step S16), and the above OFF After the lift portion of the second sheet feeding unit 6 that has been set to ON is returned to ON (step S17), the process returns to step S11 to continue the printing operation. If the print job is completed in step S12 (YES in step S12), the transport unit, paper sensor, and transport sensor that have been turned on are turned off and returned to the standby state (step S18).

  As described above, according to the image forming apparatus (printer 1) of the present invention, the conveyance control for controlling the sheet conveyance operation in each sheet feeding unit (sheet feeding unit) by the block switching control unit 102 (blocking switching unit). Section 403 (503, 603, 703), sensor control section 404 (504, 604, 704) for controlling the operation of various sensors, and lift control section 405 (505, 605, 705) for controlling the lifting / lowering operation of the paper. Switching of power supply from the power supply unit 30 (power supply unit 3; power supply means) to each operation control unit is switched to each operation control unit independently. As a result, not only the sensor, but also the drive system that performs the transport operation and the lifting operation of the paper with higher power consumption can be cut off to reduce the power consumption, and the print request (printing paper size and According to the print information such as the number of prints) and the state of the paper feed unit, the power supply can be switched between non-blocking and non-blocking for each of the operation control units, and the power consumption can be efficiently reduced.

  In addition, during the printing operation, power supply to each operation control unit of the paper feed unit on which a paper of a different type from the print request is set is partially supplied to the operation control unit that is not required by the print request in each operation control unit. Since the power supply to the operation control unit that is not required by the print request is cut off, each of the operation control units that are necessary (for example, the next print job is If it occurs, the power supply to the operation control unit that wants to start the operation immediately in response to this job without waiting time is maintained, while the power supply is supplied to the unnecessary one even if printing is in progress. Thus, the power consumption can be efficiently reduced while achieving both power saving and operation responsiveness.

  Further, in a plurality of paper feed units configured in a plurality of stages, a paper feed unit in which a paper of a type that meets the above print request (for example, the same paper size as the print request) is set as a paper feed unit A, and a print request If the paper feed unit on which a different type of paper is set is the paper feed unit B, when the paper feed unit B is arranged on the lower side of the paper feed unit A, the sheet transfer operation is performed by the cutoff switching control unit 102 Is not supplied to the conveyance control unit (conveyance unit; specifically, the conveyance roller 75, the pickup roller 73, and the branch guide 76) of the sheet feeding unit B (for example, the third sheet feeding unit 7 shown in FIG. 5). Therefore, the transport control unit of the paper feed unit B in which a different type of paper from the print request, that is, paper that is not used for printing is set and the paper transport operation is unnecessary is set. It is possible to reduce the cost of power.

  Further, when the paper feeding unit B is arranged on the lower side of the paper feeding unit A, the sensor control unit (sensor unit; specifically, the paper feeding unit B (for example, the third paper feeding unit 7 shown in FIG. 5)). Since the power supply to the transport sensor 79) is further cut off, the transport control in the paper feed unit B in which a paper of a different type from the print request, that is, a paper not used in printing is set and the paper transport operation is not required. The power consumption of the sensor control unit can be reduced together with the unit.

  Further, when the sensor control unit of the paper feeding unit A detects that there is no paper in the paper feeding unit A, the cutoff switching control unit 102 cuts off the power supply to the lift control unit of the paper feeding unit A. Therefore, the power consumption of the lift control unit can be reduced without wastefully supplying power to the lift control unit of the paper feeding unit that does not have paper.

  When the sensor control unit of the paper feeding unit A detects that there is no paper in the paper feeding unit A, information prompting the user to feed the paper is displayed on the display unit 90 (display unit). As a result, the user can visually recognize that there is no paper in the paper feed unit, and can reliably replenish (feed) paper to the paper feed unit that has run out of paper.

  Further, during a printing operation, a sensor control unit (sensor unit; specifically, a paper feeding unit (for example, the first and third paper feeding units 5 and 7 shown in FIG. 5) in which a different type of paper from the print request is set. Since the power supply to the paper sensors 57 and 77) or the lift control unit (lift unit; lift drive units 52 and 72) is cut off by the cut-off switching control unit 102, the type of paper different from the print request, that is, the paper not used for printing It is possible to reduce the power consumption of the sensor control unit or the lift control unit in the paper feed unit in which is set.

  In addition, power is supplied to the sensor control unit at a predetermined timing before the end of the printing operation (for example, immediately before the end of the printing operation) with respect to the sheet feeding unit in which power supply to the sensor control unit is cut off in this way. At the same time, the sensor control unit performs a return operation in which the status of the paper feed unit is detected. Therefore, while reducing power consumption, prepare for the next print job, that is, start the operation quickly in response to the next print job. It is possible to maintain the operation responsiveness for performing.

  Further, as described above, the power supply to the lift control unit is performed at a predetermined timing before the end of the printing operation (for example, immediately before the end of the printing operation) with respect to the paper feeding unit in which the power supply to the lift control unit is interrupted. In addition, a lift operation is performed by the lift control unit, for example, a return operation is performed in which the lifted tray that has been lowered is moved up to a position where the paper can be taken out. It is possible to maintain operation responsiveness for preparing a print job, that is, for quickly starting operation in response to the next print job. In addition, this invention can take the deformation | transformation aspect shown to the following (A)-(E).

  (A) In the above embodiment, as shown in FIG. 5, the power supply to all the lifts is turned on during printing. However, for example, the number of printed sheets is large and printing takes time (using one paper feeding unit). In the case of a print job in which continuous printing is performed), the power supply to the lift unit may be turned off particularly for a paper feed unit that does not require lift control (in the case of FIG. 5, for example, the third paper feed). The lift part of the unit 7 or the first paper feeding unit 5 may be turned off). Thereby, power consumption can be reduced more.

(B) During printing (for example, when performing the above-described continuous printing), a paper feeding unit that is not used for printing, for example, paper conveyance is not performed (for example, the third paper feeding unit 7 in the case of FIG. 5). For example, when the paper feed cassette of the third paper feed unit 7 is attached or detached to change the direction or size of the paper, or to feed (replenish) the paper whose remaining amount is low, for example, the paper is pulled out. The sensor control unit 704 of the third paper supply unit 7 is at a predetermined timing (for example, immediately before the end of printing) at which the print job (printing operation) ends after the supplied paper cassette is returned to the original fixed position. Is turned on (returned), and the paper sensor 77 controlled by the sensor control unit 704 detects the remaining amount of paper, the presence or absence of paper, the paper size, and the orientation. A recovery operation for detecting the latest state of the paper unit 7 may be performed to prepare for the next print job (maintain operation responsiveness) (the paper sensor 77 supplies power again after detecting the latest state). May be turned off). This return operation may be performed by, for example, a return control unit (not shown) provided in the main control unit 100. This return operation does not necessarily have to be performed when the paper cassette is attached or detached. In short, while the power supply to the sensor control unit 704 (paper sensor 77) is turned off, It is only necessary to check whether the state (paper size and orientation, paper presence / absence and remaining amount) has changed.
The predetermined timing at which the print job ends is specifically, for example, when the number of printed sheets is counted (counted down) by the print information setting unit 103, for example, when the predetermined number of sheets is reached after printing is started, or the remaining predetermined timing Indicates the point when the number is reached. Note that this timing may be the time when a predetermined time (time before the end of printing) has elapsed since the start of printing, for example, regardless of the number of printed sheets. In addition, the detection of attachment / detachment of the paper feed cassette is performed by a cassette sensor (see FIG. 5) in which power supply is turned on.

  (C) Regarding the modification (A), the power supply to the sheet feeding unit not used for printing, for example, the lift control unit 705 (lift driving unit 72) of the third sheet feeding unit 7 in FIG. 5 is turned off. As in the above, immediately before the end of the print job (printing operation), the power supply to the lift control unit 705 of the third paper feed unit 7 is turned on (returned) and the lift tray 711 is moved up and down. In other words, the lift tray 711 that has been lowered is raised to a predetermined position in accordance with the stacking height of the sheet, and the pickup roller 73 picks up the sheet, that is, returns to a state where the sheet can be taken out (feedable). A configuration may be adopted in which the operation is performed to prepare for the next print job (maintaining operation responsiveness).

  (D) Similarly to the above-described modification, even in the standby state as shown in FIG. 6, for example, in order to change the orientation and size of the paper, or to supply (replenish) paper with a small remaining amount, for example, the third feed When the paper cassette of the paper unit 7 is attached / detached (this attachment / detachment is also detected by the cassette sensor in the ON state as described above), the power supply to the paper sensor 77 is turned on (returned) and the paper is fed. A return operation for detecting the latest state of the third paper feed unit 7 by detecting the remaining amount of paper, presence or absence, paper size and orientation by the sensor 77 is performed by the return control unit to prepare for the next print job (operation (In this case, the paper sensor 77 may detect the latest state and then turn off the power supply again).

1 is a cross-sectional view schematically showing an internal configuration of a printer as an example of an image forming apparatus according to the present invention. FIG. 2 is an outline view schematically showing the printer shown in FIG. 1. FIG. 2 is a block diagram illustrating an example of an electrical configuration mainly related to conveyance control, sensor control, and lift control of a paper feeding unit in the printer. FIG. 3 is a functional block diagram mainly relating to power supply switching of a main control unit in the printer. FIG. 6 is a diagram illustrating an example of a power supply state of each part of a paper feed unit during printing. FIG. 6 is a diagram illustrating an example of a power supply state of each part of a paper feeding unit during standby. 3 is a flowchart illustrating an example of a power supply operation of a printer according to the present embodiment.

Explanation of symbols

1 Printer (image forming device)
2 Image forming unit (printing means)
3 Power supply (power supply means)
4 Standard paper feed unit (paper feed unit) (paper feed unit; paper feed means)
5 First paper feeding unit 5 (paper feeding unit; paper feeding means)
6 Second paper feeding unit 6 (paper feeding unit; paper feeding means)
7 Third paper feeding unit 7 (paper feeding unit; paper feeding means)
10 Printer Body 30 Power Supply Unit (Power Supply Unit)
90 Display section (display means)
100 Main control unit (return control means)
102 Cutoff switching control unit (cutoff switching means)
104 Display control unit (display means)
42, 52, 62, 72 Lift drive unit 43, 53, 63, 73 Pickup roller 45, 55, 65, 75 Transport roller 47, 57, 67, 77 Paper sensor 48, 58, 68, 78 Cassette sensor 49, 59, 69, 79 Transport sensor 403, 503, 603, 703 Transport control unit 404, 504, 604, 704 Sensor control unit 405, 505, 605, 705 Lift control unit 411, 511, 611, 711 Lift tray

Claims (9)

Printing means for printing an image;
Paper feeding means for feeding paper to the printing means;
Power supply means for supplying power to each part of the device;
The power supply unit for each operation control unit including a conveyance control unit that controls the conveyance operation of the sheet, a sensor control unit that controls the operation of various sensors, and a lift control unit that controls the lifting and lowering operation of the sheet. An image forming apparatus comprising: a cutoff switching unit that performs switching between cutoff and non-blocking of power supply to each operation control unit independently. The paper feeding means comprises a plurality of paper feeding units,
The cut-off switching means is an operation control unit that does not require power supply to each operation control unit of the paper feed unit on which a paper of a different type from the print request is set during a printing operation. The image forming apparatus according to claim 1, wherein the image forming apparatus is partially blocked. The plurality of paper feeding units are configured in a plurality of stages,
A paper feed unit in which a type of paper meeting the print request in the plurality of paper feed units is set as a paper feed unit A, and a paper feed unit in which a type of paper different from the print request is set is called a paper feed unit B. Then
The shut-off switching unit shuts off power supply to the transport control unit of the paper feed unit B that does not require a paper transport operation when the paper feed unit B is arranged on the lower side of the paper feed unit A. The image forming apparatus according to claim 2.   The shut-off switching unit further cuts off the power supply to the sensor control unit of the paper feeding unit B when the paper feeding unit B is arranged on the lower side of the paper feeding unit A. 3. The image forming apparatus according to 3.   When the sensor control unit of the paper feed unit A detects that there is no paper in the paper feed unit A, the cutoff switching unit cuts off the power supply to the lift control unit of the paper feed unit A. The image forming apparatus according to claim 3, wherein:   When the sensor control unit detects that there is no sheet in the sheet feeding unit A, the apparatus further comprises display means for displaying information prompting the user to feed the sheet to the sheet feeding unit A. The image forming apparatus according to claim 5.   3. The cutoff switching unit cuts off power supply to the sensor control unit or the lift control unit of the paper feeding unit on which a paper of a type different from a print request is set during a printing operation. The image forming apparatus according to claim 6. For the paper feeding unit in which power supply to the sensor control unit is cut off,
Return at a predetermined timing before the end of the printing operation, causing the shut-off switching unit to switch to the non-shut-off to supply power to the sensor control unit, and to perform a return operation that causes the sensor control unit to detect the state of the paper feed unit The image forming apparatus according to claim 7, further comprising a control unit. For a paper feeding unit that is cut off from power supply to the lift control unit,
At a predetermined timing before the end of the printing operation, a return control for causing the shut-off switching means to switch to the non-shut-off to supply power to the lift control unit and to perform a return operation for causing the lift control unit to perform a paper lifting operation. 8. The image forming apparatus according to claim 7, further comprising means.

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