JP2012184072A - Image forming apparatus, image forming method, program, and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce power consumption during paper feed.SOLUTION: The number of stages of cassettes with paper sheets (types) set thereon, and the stage of a motor to be driven is registered in a memory 200 of an ASIC. During a print job, motors are controlled on the basis of the table. When A4 normal paper is set in the second stage of additional cassettes, the paper feed starts by means of rollers for the cassette 2. When the leading end of the paper reaches the rollers for the cassette 1, the rollers for the cassette 1 are selected. When the leading end of the paper reaches the rollers for the body, the rollers for the body are selected (112).

Description

  The present invention relates to an image forming apparatus, an image forming method, a program, and a recording medium with reduced power consumption.

  The ink jet printer can install an additional cassette in addition to the paper feed cassette mounted on the main body. When paper is fed from the additional cassette of the printer for printing, there is also a paper transport motor in the paper feeding cassette, which carries the paper to the main unit. In the case of a printer that can mount a plurality of cassettes, the motors of the cassettes are driven simultaneously. The motor mounted on the additional cassette is often used at a relatively low cost, and the efficiency is poor, so the power consumption is large. On the other hand, since the motor mounted on the main body side is frequently used, a motor considering power consumption is selected. For example, in Patent Document 1, each motor is driven at a different phase in order to reduce the power consumption of the motor when paper is fed from an extension cassette.

  However, the above-described extension cassette has a problem that power is wasted because a motor in an unnecessary portion is driven when feeding paper.

The present invention has been made in view of the above-described problems.
It is an object of the present invention to provide an image forming apparatus, an image forming method, a program, and a recording medium that reduce power consumption during a paper feeding operation.

  The present invention provides an image forming apparatus that feeds and prints a sheet from a stacking unit of a main body on which sheets are stacked and a plurality of additional stacking units according to the type of the sheet and the number of stages of the additional stacking unit. And a control unit for selecting the driving motor with reference to the registration unit when the paper is fed and printed. And

  According to the present invention, it is possible to determine whether or not it is necessary to drive a plurality of motors depending on the type of paper, and only the necessary cassette motor can be operated. Power consumption can be reduced. Also, when feeding A3 paper, etc., to prevent jamming, multiple motors are driven simultaneously, the drive torque of each motor is optimally distributed, and the motors are driven with the minimum necessary power consumption. Unnecessary power consumption can be reduced.

1 shows an ink jet recording apparatus (image forming apparatus) to which the present invention is applied. 1 shows a configuration of a control unit of an image forming apparatus. It is a figure explaining the conventional paper feeding operation. The motor control table of Example 1 of this invention is shown. The structure of Example 2 of this invention is shown. It is a figure explaining operation | movement of Example 3 of this invention. The structure of Example 4 of this invention is shown.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the present invention, when feeding paper from the additional cassettes stacked in a plurality of stages, the driving motor is freely controlled. In other words, when paper is supplied from the extension cassette, it is detected that the sheet has reached the main body motor, and the motor drive on the extension cassette side is quickly stopped to enable a printing operation with low power consumption.

  FIG. 1 shows an ink jet recording apparatus (image forming apparatus) to which the present invention is applied. FIG. 1A shows the side surface, and FIG. 1B shows the plane. In FIG. 1, a carriage 33 is slidably held in a main scanning direction by a guide rod 31 which is a guide member horizontally mounted on the left and right side plates 21A and 21B constituting the frame 21 and a stay 32, and a main scanning motor (not shown). Thus, the moving scanning is performed in the arrow direction (carriage main scanning direction) in FIG.

  The carriage 33 includes a recording head 34 including four droplet discharge heads that discharge ink droplets of each color of yellow (Y), cyan (C), magenta (M), and black (Bk). Are arranged in a direction crossing the main scanning direction, and the ink droplet ejection direction is directed downward.

  The ink-jet head constituting the recording head 34 uses a piezoelectric actuator such as a piezoelectric element, a thermal actuator that uses a phase change caused by film boiling of a liquid using an electrothermal transducer such as a heating resistor, and a metal phase change caused by a temperature change. A shape memory alloy actuator, an electrostatic actuator using an electrostatic force, or the like provided as pressure generating means for generating a pressure for discharging a droplet can be used.

  In the present invention, in addition to driving all the ink ejection ports simultaneously, it can be driven by being divided in time. If all the ink ejection ports are driven simultaneously, there will be problems such as a decrease in recording quality due to the influence of crosstalk between each ink ejection port, and an increase in the capacity of the power supply due to the temporary need for a large current. These problems can be avoided by time division driving.

  A driver IC is mounted on the recording head 34 and connected to a control unit (not shown) via a harness (flexible print cable) 22. In addition, the carriage 33 is equipped with a sub tank 35 for each color for supplying ink of each color to the recording head 34. As described above, each color sub-tank 35 is supplementarily supplied with ink of each color from the ink cartridge 10 of each color mounted in the cartridge loading unit 4 via the ink supply tube 36 of each color. The cartridge loading 4 is provided with a supply pump unit for feeding the ink in the ink cartridge 10, and the ink supply tube 36 is held on the rear plate 21 </ b> C constituting the frame 21 by the locking member 25. Has been.

  On the other hand, as a paper feeding unit for feeding the papers 42 stacked on the paper stacking unit (pressure plate) 41 of the paper feeding tray 2, a half-moon roller (feeding) that separates and feeds the papers 42 one by one from the paper stacking unit 41. A separation pad 44 made of a material having a large friction coefficient is provided opposite to the sheet roller 43) and the sheet feeding roller 43. The separation pad 44 is urged toward the sheet feeding roller 43 side. In order to feed the sheet 42 fed from the sheet feeding unit to the lower side of the recording head 34, a guide member 45 that guides the sheet 42, a counter roller 46, a transport guide member 47, and a tip pressure roller. And a holding belt 48 which is a conveying means for electrostatically attracting the fed paper 42 and conveying it at a position facing the recording head 34.

  The conveyor belt 51 is an endless belt, and is configured to wrap around the conveyor roller 52 and the tension roller 53 and circulate in the belt conveyance direction (sub-scanning direction). The transport belt 51 is, for example, a surface layer that is a sheet adsorbing surface formed of a pure resin material having a thickness of about 40 μm that is not subjected to resistance control, for example, ETFE pure material, and resistance control by carbon using the same material as the surface layer. And a back layer (medium resistance layer, earth layer).

  A charging roller 56, which is a charging means for charging the surface of the conveyor belt 51, is provided. The charging roller 56 contacts the surface layer of the conveyor belt 51 and is arranged to rotate according to the rotation of the conveyor belt 51. As a pressure, a predetermined pressing force is applied to both ends of the shaft. The transport roller 52 also serves as an earth roller, and is in contact with the middle resistance layer (back layer) of the transport belt 51 and is grounded.

  In addition, a guide member 57 is disposed on the back side of the conveyance belt 51 corresponding to the printing area by the recording head 34, and the guide member 57 has two rollers (a conveyance roller 52 and a conveyance roller 52) whose upper surface supports the conveyance belt 51. By projecting toward the recording head 34 side from the tangent line of the tension roller 53), high-precision flatness of the conveyor belt 51 is maintained. The transport belt 51 rotates in the belt transport direction (sub-scan direction) in FIG. 1B when the transport roller 52 is rotationally driven by a sub-scan motor (not shown).

  Further, as a paper discharge unit for discharging the paper 42 recorded by the recording head 34, a separation claw 61 for separating the paper 42 from the conveying belt 51, a paper discharge roller 62, and a paper discharge roller 63 are provided. The sheet discharge tray 3 is provided below the sheet discharge roller 62, and the height from the sheet discharge roller 62 and the sheet discharge roller 63 to the sheet discharge tray 3 increases the amount that can be stocked in the sheet discharge tray 3. To some extent.

  Further, a duplex unit 71 is detachably mounted on the back surface of the apparatus body 1. The duplex unit 71 takes in and reverses the sheet 42 returned by the reverse rotation of the transport belt 51, and again with the counter roller 46. Paper is fed between the conveyor belt 51. The upper surface of the duplex unit 71 is a manual feed tray 72.

  Further, as shown in FIG. 1B, a maintenance / recovery mechanism 81 including a recovery means for maintaining and recovering the nozzle state of the recording head 34 is provided in a non-printing area on one side of the carriage 33 in the scanning direction. The maintenance and recovery mechanism 81 is provided with cap members (hereinafter referred to as “caps”) 82a to 82d (hereinafter referred to as “caps 82” when not distinguished from each other) for capping each nozzle surface of the recording head 34, and nozzles. A wiper blade 83, which is a blade member for wiping the surface, and an empty discharge receiver 84 for receiving a droplet when performing an empty discharge for discharging a droplet that does not contribute to recording in order to discharge the thickened recording liquid. The cap 82a is a suction and moisture retention cap, and the other caps 82b to 82d are moisture retention caps.

  The waste liquid of the recording liquid generated by the maintenance / recovery operation by the maintenance / recovery mechanism 81, the ink discharged to the cap 82, the ink adhered to the wiper blade 83 and removed by the wiper cleaner, and the ink ejected idle to the idle ejection receptacle 84 Is discharged and stored in a waste liquid tank (not shown).

  Further, as shown in FIG. 1B, in order to discharge the recording liquid thickened during recording or the like to the non-printing area on the other side in the scanning direction of the carriage 33, droplets that do not contribute to recording are discharged. An empty discharge receiver 88 that receives liquid droplets when performing empty discharge is disposed, and the empty discharge receiver 88 includes an opening 89 along the nozzle row direction of the recording head 34.

  Further, a communication circuit unit (interface) such as a USB for transmitting / receiving data to / from the host is provided on the inner rear side of the apparatus main body 1, and a control circuit board for controlling the entire image forming apparatus is provided. Is provided.

  In the ink jet recording apparatus configured as described above, the sheets 42 are separated and fed one by one from the sheet feed tray 2, and the sheets 42 fed substantially vertically upward are guided by the guide 45, and the transport belt 51 and the counter roller 46, and the leading end is guided by the conveying guide 47 and pressed against the conveying belt 51 by the leading end pressing roller 49, and the conveying direction is changed by approximately 90 °.

  At this time, a positive voltage output and a negative output are alternately repeated from the AC bias supply unit to the charging roller 56 by a control circuit (not shown), that is, a charging voltage pattern in which an alternating voltage is applied and the conveying belt 51 alternates. That is, plus and minus are alternately charged in a band shape with a predetermined width in the sub-scanning direction, which is the circumferential direction, and when the sheet 42 is fed onto the conveying belt 51 charged alternately with plus and minus, the sheet 42 is fed. Is adsorbed by the conveyor belt 51, and the paper 42 is conveyed in the sub-scanning direction by the circular movement of the conveyor belt 51.

  Therefore, by driving the recording head 34 according to the image signal while moving the carriage 33, ink droplets are ejected onto the stopped paper 42 to record one line, and after the paper 42 is conveyed by a predetermined amount, Record the next line. Upon receiving a recording end signal or a signal that the trailing edge of the paper 42 has reached the recording area, the recording operation is finished and the paper 42 is discharged onto the paper discharge tray 3.

  During printing (recording) standby, the carriage 33 is moved to the maintenance / recovery mechanism 81 side, the recording head 34 is capped by the cap 82, and the nozzles are kept in a wet state to prevent ejection failure due to ink drying. To do. In addition, the recording head 34 is capped with the cap 82, and the recording liquid is sucked from the nozzles by a suction pump (not shown) (referred to as “nozzle suction” or “head suction”) to recover the thickened recording liquid or bubbles. Perform the action. In addition, an idle ejection operation for ejecting ink not related to the recording is performed before the start of recording or during the recording, thereby maintaining the stable ejection performance of the recording head 34.

  FIG. 2 shows the configuration of the control unit of the image forming apparatus. This control unit controls the entire image forming apparatus, and controls the CPU 301 for controlling the sheet conveying operation and the recording head moving operation, the program executed by the CPU 301, the ROM 302 for storing other fixed data, the image data and the like temporarily. A RAM 303 for storing data, a rewritable nonvolatile memory 304 for holding data even while the apparatus power is shut off, image processing for performing various signal processing and rearrangement on image data, and input / output signals. And an ASIC 305 for processing.

  The control unit also generates an I / F 306 for transmitting and receiving data and signals to and from the host side, and a drive waveform for driving the recording head 34, and selectively drives the pressure generating means of the recording head 34. A print control unit 308 that outputs image data and various data to the head driver 312, a main scanning motor driving unit 309 for driving the main scanning motor 313, and a sub scanning motor driving unit 311 for driving the sub scanning motor 315. An AC bias supply unit 310 that supplies an AC bias to the charging roller 56, a detection pulse from the linear encoder 314 and the wheel encoder 316, and an I / O 307 for inputting detection signals from various other sensors. Yes. An operation panel 317 for inputting and displaying information necessary for the image forming apparatus is connected to the control unit.

  The control unit uses an I / F 306 to transmit print data generated by a host printer driver 318 such as an information processing device such as a personal computer, an image reading device such as an image scanner, or an imaging device such as a digital camera via a cable or a network. Receive. Then, the CPU 301 of the control unit reads and analyzes the print data in the reception buffer included in the I / F 306, performs necessary image processing, data rearrangement processing, and the like in the ASIC 305, and transfers them to the print control unit 308. Image data and drive waveforms are output from the print control unit 308 to the head driver 312 at a required timing. The generation of dot pattern data for image output may be performed, for example, by storing font data in the ROM 302, or the image data is converted into bitmap data by the host-side printer driver 318 and transferred to this apparatus. You may make it do. Here, the printer driver 318 is used.

  The drive waveform generation unit of the print control unit 308 includes a D / A converter, an amplifier, and the like that perform D / A conversion on the drive pulse pattern data stored in the ROM 302 and read out by the CPU 301. A drive waveform composed of drive pulses is output to the head driver 312, and the head driver 312 prints the print control unit based on image data (dot pattern data) corresponding to one line of the recording head input serially. The recording head 34 is driven by selectively applying a driving pulse constituting a driving waveform supplied from the driving waveform generator 308 to the pressure generating means of the recording head 34. The head driver 312 is, for example, a shift register that inputs serial data that is a clock signal and image data, a latch circuit that latches a register value of the shift register using a latch signal, and an output value of the latch circuit that changes the level. A level conversion circuit (level shifter) and an analog switch array (switch means) whose on / off is controlled by this level shifter, etc., and the required drive pulse included in the drive waveform by controlling the on / off of the analog switch array Is selectively applied to the pressure generating means of the recording head.

  FIG. 3 is a diagram for explaining a conventional paper feeding operation. The image forming apparatus (printer) 101 can be mounted with a plurality of additional cassettes. Reference numerals 102 and 103 denote additional cassettes. The user stocks paper 104 in each cassette in advance. When the user sets the paper size and type when printing, the printer automatically determines which cassette paper to print on, and starts paper feeding. When a print job is sent, the printer starts a paper feeding operation 107 by, for example, a guide roller 105 driven by a motor and a passive roller 106 for suppressing paper.

  The motor drive of each cassette is controlled by the ASIC 305 of the printer main body 101. However, there is a case where the guide roller of the cassette that does not need to be operated is also operated due to the aggregation of signal lines and the reduction of harnesses. Generally, a printer is equipped with sensors 108, 109, and 110 for detecting the leading and trailing edges of a sheet. By detecting the sensor, it is possible to determine the moving state of the paper, and when the paper is jammed during printing, it is possible to detect the location where the paper jam has occurred.

  FIG. 4 illustrates a table for controlling the motor according to the first embodiment. In the first embodiment, as shown in FIG. 4, a table in advance in the memory 200 of the ASIC 305 indicates how many stages of the cassette the paper (type) is set and what level of motor is driven with what torque. When the user executes a print job, the ASIC 305 refers to the table and controls the motor.

  Since the motor load varies depending on the type of paper, wasteful power consumption can be suppressed by feeding paper with the minimum torque possible. For example, A4 plain paper is set in the second stage of the expansion cassette (103 in FIG. 2). When printing, first, feeding is started by the rollers (motors) 105 and 106 of the cassette 2, When the leading edge of the paper reaches the rollers 105 and 106 of the cassette 1, the sensor 109 detects the leading edge of the paper and switches to the roller (motor) of the cassette 1, and when the leading edge of the paper reaches the roller of the main body, An operation 112 of switching to a roller (motor) is performed.

  In the case of A3 high-grade paper, feeding is started with the roller of cassette 2, and when the leading edge of the paper reaches the roller of cassette 1, both rollers (motors) of cassette 1 and cassette 2 are driven, When reaching the roller of the main body, both the roller of the main body and the roller (motor) of the cassette 1 are driven. As a result, driving of an appropriate roller (motor) according to the paper type is performed, so that wasteful power consumption can be suppressed and occurrence of paper jam due to insufficient torque can be prevented. Thus, according to Example 1, motor drive is optimized and power consumption can be suppressed.

  FIG. 5 shows a configuration of the second embodiment of the present invention. As shown in FIG. 5, a PSoC (Programmable SoC) 204 is mounted on the printer main body, and the PSoC 204 measures the power of the power supply of the main body cassette motor 202 and the additional cassette motor 203. Since motors generally vary in efficiency and deteriorate, the PSoC 204 checks the power consumption of the motors 202 and 203 and reflects the result on the table (FIG. 4) in the memory 200 via the ASIC 201.

  A specific feedback method will be described below. First, a current monitoring program is installed in the PSoC 204 in advance, and the PSoC 204 measures the current value flowing through the cassette motor 202 and the extension cassette motor 203 of the main body, and stores the measurement result in the memory 200 installed in the printer. To do. The current measurement by the PSoC 204 may be performed by an inspection before shipping the printer, or may be performed by a user from a printer driver.

  After feedback, the efficiency of the motor is known to be good or bad, so paper feeding operation with less power consumption can be achieved by appropriately allocating torque to the efficient motor and the inefficient motor as long as jam does not occur. Can be performed. Thus, in Example 2, a more accurate table can be created based on actual measurement.

  FIG. 6 is a diagram for explaining the operation of the third embodiment of the present invention. When the paper type stocked in each cassette is the same and the paper selection of the printer is automatic selection, when the continuous printing is performed, the main cassette is out of paper, and the configuration of the extension cassette is described in two stages. To do.

  When the motor efficiency of the expansion tray confirmed by the PSoC 204 is better than the motor efficiency of the upper expansion tray 102 than the motor efficiency of the upper expansion tray 102, the first stage (102) paper 115 is fed. In contrast, since the power consumption is reduced when the second stage (103) paper 114 is fed, the paper is fed from the lower extension tray 103.

  In addition, since the motor has a characteristic that the efficiency decreases when the motor generates heat, by reducing the heat generated by appropriately sharing the operation, the power consumption is reduced as a result. Furthermore, it is possible to reduce power consumption by distributing paper feeding operations according to the job amount. In the distributed operation, for example, the motor temperature and efficiency are preliminarily tabulated in the memory 200 at the printer design stage, and the distributed operation is performed by comparing with the motor temperature detected by the temperature thermistor installed in the motor during actual operation.

  Thus, in Example 3, it is possible to reduce power consumption in response to changes in motor efficiency due to heat during continuous operation.

  FIG. 7 shows a configuration of Embodiment 4 of the present invention. The user does not know which paper feed cassette motor is efficient and what the operating rate is. Therefore, in the fourth embodiment, paper cassette information is notified to the user from the printer driver on the operation panel 317 (FIG. 2) or the screen of the personal computer. For example, as shown in FIG. 7, the operation rate and efficiency of the paper feed tray are displayed, advice to the user is displayed, and the user selects the tray by referring to the display content (paper feed cassette information). As a result, power consumption can be further suppressed. Thus, in Example 4, the user can easily implement energy saving measures.

  According to the present invention, a storage medium storing software program codes for realizing the functions of the above-described embodiments is supplied to a system or apparatus, and the computer (CPU or MPU) of the system or apparatus is stored in the storage medium. It is also achieved by reading and executing the program code. In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiment. As a storage medium for supplying the program code, for example, a hard disk, an optical disk, a magneto-optical disk, a nonvolatile memory card, a ROM, or the like can be used. Further, by executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also an OS (operating system) operating on the computer based on an instruction of the program code. A case where part or all of the actual processing is performed and the functions of the above-described embodiments are realized by the processing is also included. Further, after the program code read from the storage medium is written into a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, the function expansion is performed based on the instruction of the program code. A case where the CPU or the like provided in the board or the function expansion unit performs part or all of the actual processing and the functions of the above-described embodiments are realized by the processing is included. Further, the program for realizing the functions and the like of the embodiments of the present invention may be provided from a server by communication via a network.

200 memory 201 ASIC
202 Main unit cassette motor 203 Additional cassette motor 204 PSoC

JP-A-8-156354

Claims (7)

  In an image forming apparatus that feeds and prints the paper from the stacking means of the main body on which the paper is loaded and a plurality of additional stacking means, the stack is driven according to the type of the paper and the number of stages of the additional stacking means An image forming apparatus comprising: a registration unit that registers a motor of the unit; and a control unit that selects the motor to be driven with reference to the registration unit when the paper is fed and printed.   Measuring means for measuring the power consumption of the motor of the loading means, and the control means drives based on the measured power consumption with reference to the registration means in which the measurement result of the measurement means is registered The image forming apparatus according to claim 1, wherein a motor is selected.   2. The image forming apparatus according to claim 1, wherein when the paper is continuously fed and printed, the paper is alternately fed from the additional stacking unit.   2. The image according to claim 1, further comprising display means for displaying the efficiency and operating rate of the motor of the loading means for each loading means, and presenting efficient use information of the loading means to the user. Forming equipment.   In an image forming method for feeding and printing the paper from the stacking means of the main body on which the paper is stacked and a plurality of additional stacking means, the stacking is driven according to the type of the paper and the number of stages of the additional stacking means An image forming method comprising: a registration step of registering a motor of the means; and a control step of selecting the motor to be driven with reference to the registration step when the paper is fed and printed.   A program for causing a computer to realize the image forming method according to claim 5.   A computer-readable recording medium on which a program for causing a computer to realize the image forming method according to claim 5 is recorded.

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