JP2008080669A - Control method of printer, control program of printer and printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable it to perform a high-speed printing operation which satisfies a required specification of a product even with a smaller-scale power supply configuration. <P>SOLUTION: In a printer equipped with a carriage which carries a recording head for ejecting an ink from the ink ejection part and making a record in a recording medium and a printing mechanism which includes a carriage driving mechanism for conveying the carriage along with the recording medium and a recording medium transfer mechanism for conveying the recording medium, a carriage drive profile control, by which a drive current required for driving the printing mechanism is estimated according to the printing conditions (S1 to S9) and the profile of a carriage drive which is performed by the carriage drive mechanism according to the estimated drive current is controlled (S10 to S14), is carried out. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a carriage equipped with a recording head for discharging ink from an ink discharge portion to perform recording on a recording medium, a carriage drive mechanism for transporting the carriage along the recording medium, and a recording medium for transporting the recording medium. The present invention relates to a control method for a printing apparatus having a printing mechanism including a transport mechanism, a control program for the printing apparatus, and the printing apparatus.

  Conventionally, ink jet recording apparatuses have been widely used for printing characters and images for various uses such as office use and home use (hereinafter, printing, recording, image formation, etc. as synonyms for printing operations as necessary). And other terms).

  The ink jet recording apparatus performs printing by ejecting ink droplets from a plurality of ink ejection ports provided in the recording head and attaching them to a recording medium. The plurality of ink ejection openings provided in the recording head are parallel to the conveyance direction of a recording medium (hereinafter, terminology such as “paper” is used if necessary, but the material is arbitrary, such as paper or plastic). Are arranged in various directions.

  As a scanning method of the ink jet recording apparatus, a serial scanning method is often adopted. In this serial scanning method, after the recording head is driven while the main scanning scan is performed in the direction intersecting the conveyance direction (sub-scanning direction) of the recording medium with the carriage mounted with the recording head, the recording for one main scanning is completed. A predetermined amount of paper is fed. Thereafter, by repeating the operation of recording an image for the next main scanning on the recording medium that has been stopped again, recording is performed on the entire recording medium.

  FIG. 2 shows a configuration of a main part of a general ink jet recording apparatus. In FIG. 2, reference numeral 101 denotes a recording head having an ink tank, and 102 denotes a carriage on which the recording head 101 is mounted. A guide shaft 103 is inserted into the bearing portion of the carriage 102 so as to be slidable in the main scanning direction, and both ends of the shaft are fixed to the chassis 114. The drive of the drive motor 105 which is a carriage drive means is transmitted via the belt 104 which is a carriage drive transmission means engaged with the carriage 102 so that the carriage 102 can move in the main scanning direction.

  During recording standby, the recording paper 115 is stacked on the paper supply base 106, and at the start of recording, the recording paper is supplied by a paper supply roller (not shown). In order to transport the fed recording paper, the transport roller 110 is rotated through a gear train (motor gear 108, transport roller gear 109) serving as transmission means by the driving force of the paper transport motor 107 serving as a DC motor. In response to this, the recording paper 115 is conveyed by an appropriate feeding amount by the pinch roller 111 which is pressed against the conveyance roller 110 by a pinch roller spring (not shown) and rotates in a driven manner. The conveyance amount of the recording paper 115 is managed by detecting and counting the slits of the code wheel (rotary encoder film) 116 press-fitted into the conveyance roller gear 109 with the encoder sensor 117, thereby enabling highly accurate conveyance control. .

  Printing is performed by alternately driving the carriage drive system (CR drive system) and the transport roller drive system (LF drive system), and the total time of these operations determines the final printing speed (throughput). To do.

  As an efficient way to move the carriage drive system and recording medium transport system to improve printing speed, acceleration / deceleration printing that shortens the carriage drive time by reducing the carriage scanning range, carriage operation and transport operation The cross control etc. which perform simultaneously are proposed.

For example, in Patent Document 1 described below, the current value supplied to the carriage drive source is controlled in order to learn the operation of the carriage and realize a carriage drive waveform suitable for the intended acceleration / deceleration printing. However, in such a configuration, image data that requires a large amount of ejection from the power supply of the printing apparatus and the worst acceleration / deceleration conditions that maximize the carriage load are designed and the target acceleration / deceleration is performed. Current must be supplied to the carriage to perform printing.
JP 2003-63085 A

  In the configuration of the conventional general ink jet recording apparatus as shown in FIG. 2, during printing on the recording medium, the recording medium is transported only by driving the transport motor 107 and printing is performed. At this time, the power of the conveyance motor 107 is transmitted to the recording medium by a discharge roller 113 that is mechanically connected to the conveyance roller 110 and transmits the power, and the recording medium is conveyed. In such a configuration, after the feeding of the recording medium is completed, a driving roller that positively powers the recording medium remaining on the upstream side (feeding start position side) of the conveying roller 110 and conveys the recording medium. Is not usually present.

  During printing, the recording medium is conveyed in the sub-scanning direction by a predetermined amount, and the carriage 102 is scanned to print an image for one scan. This operation is repeated, and after the printing of all the areas in one page is completed, the recording medium is discharged to a predetermined position, and the next page is fed. The CR drive profile is set in advance so as to satisfy a predetermined operation, and the transport roller is driven outside the printing area during one scan. In such a configuration, the amount of current increases most when the acceleration / deceleration of the CR motor 105 and the conveyance motor 107 is added, or the drive of the recording head 101 during printing and the drive of the CR motor 105 are added. The power supply system must be designed so that this operation can be realized.

  FIG. 3 shows changes in drive current values of the carriage and the recording medium transport motor in the configuration of FIG.

  FIG. 3 shows a carriage, a conveyance motor drive speed profile, a current amount change in each element (drive motor, discharge), and a total current amount change from the top in a certain drive sequence. The speed profile of the carriage drive motor is roughly divided into an acceleration area 31, a constant speed area 32, and a deceleration area 33. The current amount Icr of the carriage drive motor is indicated by a solid line, the current amount of the transport motor is indicated by a dotted line, and the discharge current amount Ihead is indicated by an oblique line. The sum of the above current amounts is the total current amount. In particular, the portion where acceleration / deceleration of the carriage drive motor and the acceleration / deceleration of the recording medium transport motor overlap, and the portion where discharge and the carriage constant speed region overlap are regions of large current consumption. .

  On the other hand, multi-functionalization of ink jet recording apparatuses in recent years has progressed. For example, in an apparatus having double-sided printing, a cassette paper feed mechanism, etc., the mechanical mechanism of the recording medium conveyance system is becoming more complex as shown in FIG.

  In the configuration of FIG. 4, the recording medium is conveyed along the path indicated by the dotted arrow, the carriage 102 performs main scanning on the platen 112, ink is ejected at this position, and printing on the recording medium is performed. The recording medium is transported by a transport roller 110, a paper discharge roller 113, a paper feed roller 118, and a double-sided roller 119.

  In such a configuration, it is the operation of the conveyance roller 110 that mainly controls the conveyance of the recording medium during printing. The recording medium 121 is conveyed from the paper feeding cassette 120 to the conveying roller 110, and the double-sided roller 119 is used to move the recording medium in a separately provided double-sided path.

  To improve the printing speed, the carriage drive system and the recording medium transport system can be moved efficiently by reducing the carriage scanning range to reduce the carriage drive time, and the carriage operation and transport. For example, cross control for performing the operation simultaneously. The former is based on the idea of reducing the required time during printing to the minimum.

  In order to optimize each operation in order to improve the printing speed of the entire printing sequence, it is necessary to minimize the time of the recording medium conveying operation other than printing in addition to the optimization of the operation during printing. That is, it is necessary to perform control so that the time required for paper feeding and paper discharge is reduced and the printing operation is not stopped. Furthermore, when double-sided printing is taken into account, the time to transport the recording medium to the double-sided path is added, and how to shorten the paper feeding, paper discharge, and double-sided operations other than during printing is an effort to improve the printing speed It becomes a point.

  FIG. 5 schematically shows how the recording medium moves in the configuration of FIG. In FIG. 5, in addition to the recording medium (1) 122 being printed, a total of 3 recording mediums (2) 123 to be printed next and recording medium (3) 124 in consideration of double-sided printing are included in the mechanism. There is a single recording medium. In such a configuration, if the recording medium (1) is not stopped and the recording media (2) and (3) can be conveyed as close to the conveying roller 110 as possible, the entire printing sequence can be performed at a higher speed. Can be

  In general, in order to realize an ink jet recording apparatus that satisfies the operations shown in FIGS. 4 and 5, a power supply system having a larger electric capacity than the ink jet recording apparatus having the basic configuration shown in FIG. 2 is required. Become. As shown in FIG. 5, this is because the recording medium (1) and the carriage 102 are driven so as to realize the minimum printing time based on the control such as acceleration / deceleration printing and cross control, and further during printing. This is because an operation for transporting the subsequent recording medium (2) and recording medium (3) must also be performed.

  However, if the drive as shown in FIG. 5 is set under all conditions, for example, in a form satisfying the material, size, etc. of the recording member, a power supply design that allows a very large current value compared to the conventional machine can be obtained. It is necessary, and it is also possible that the configuration of the inkjet printer that has recently been reduced in price is broken.

  As described above, in recent years, it has been required to configure a printer with a smaller power supply configuration while satisfying required product specifications such as duplex printing and cassette feeding.

  An object of the present invention is to enable a high-speed printing operation that satisfies a required product specification even in a smaller power supply configuration.

  In order to solve the problems, in the present invention, a carriage on which a recording head that discharges ink from an ink discharge portion to record on a recording medium is mounted, a carriage driving mechanism that transports the carriage along the recording medium, and the above Method of controlling printing apparatus having printing mechanism including recording medium conveying mechanism for conveying recording medium, control program for printing apparatus, and estimation of driving current required for driving of printing mechanism according to printing conditions in printing apparatus And the structure which implements the carriage drive profile control which controls the profile of the carriage drive performed by the said carriage drive mechanism according to the estimated drive current was employ | adopted.

  In order to estimate the driving current necessary for driving the printing mechanism, the recording head driving current from the ink ejection amount of the recording head necessary for printing, which is estimated according to the printing conditions, and the carriage driving mechanism necessary for printing. The drive current of the recording medium, the drive current of the recording medium transport mechanism necessary for printing, and the like can be referred to. Among these, the drive current of the recording medium transport mechanism can be estimated according to conditions such as whether or not to drive the recording medium transport means other than the sub-scanning drive system for carrying in the recording medium or duplex printing. Furthermore, in order to estimate the drive current required for driving the printing mechanism, it is possible to refer to printing conditions, particularly conditions such as the size or thickness of the designated recording medium.

  According to the above configuration, the driving current necessary for driving the printing mechanism is estimated according to the printing conditions, and the carriage driving profile performed by the carriage driving mechanism is controlled according to the estimated driving current. By controlling the carriage drive profile so as not to exceed the maximum current that can be supplied, a smaller power supply unit can be used without waste, and as fast as possible without causing an overload of the power supply unit. Can do. That is, according to the present invention, even with a smaller power supply configuration, the required product specifications can be satisfied, and a printing operation with a higher throughput than before can be performed even with a power supply unit with a particularly small capacity. Has an excellent effect.

  Hereinafter, as an example of the best mode for carrying out the present invention, a configuration of an ink jet recording apparatus will be described. The recording mechanism of the ink jet recording apparatus is configured in the same manner as that shown in FIG. 2, and the recording medium transport system is configured to perform double-sided recording as shown in FIGS.

  FIG. 6 schematically shows the relationship between the carriage drive speed waveform profile in the carriage drive mechanism shown in FIG. 2, the ejection drive of the head for printing, the carriage acceleration change, the current amount, and the like. FIG. 6 shows one set of a carriage acceleration section 61, a constant speed section 62, and a deceleration section 63.

  Since the carriage transitions between the stopped state and the moving state, as shown in FIG. 6, in the acceleration region, the carriage rises to the target speed with a constant acceleration, and after driving in the constant speed region, the deceleration zone is set. The operation of stopping after that is repeated.

  In particular, printing (ink ejection) on a recording medium is not performed only in a state where the carriage enters a constant speed region, but is also performed during so-called acceleration in which printing is performed even during acceleration / deceleration as described in Patent Document 1. By performing printing (printing during deceleration), throughput can be improved.

  Therefore, in FIG. 6, as clearly shown by comparing the print area indicated by hatching in the upper part of FIG. 6 with the acceleration graph in the center of FIG. 6, the print area is at the end of the acceleration section 61 and the start of the deceleration section 63. Drive control is performed so that 64 overlaps.

  In the printing during acceleration (printing during deceleration) as shown in FIG. 6, the change in the motor driving current (carriage driving current) Icr of the carriage transport system is as shown in the lower part of FIG. A large motor drive current is required in the acceleration / deceleration region, and a drive current sufficient to balance the steady load is required in the constant speed region. Further, in the print section 64, as shown by Ihead (thick broken line) in the lower part of FIG. 6, an ejection current necessary for ejecting ink from the head is necessary, and the necessary total current value during recording is at least the sum of Icr + Ihead (thin broken line). ) Is required.

  As apparent from FIG. 6, since the large carriage drive current Icr and the discharge current amount Ihead are added to the area where acceleration / deceleration printing is performed, a larger current is consumed than when acceleration / deceleration printing is not performed. When the maximum current value allowed by the power supply is Imax, in FIG. 6, Icr + Ihead is a larger value in a section than Imax, and a failure occurs as an electrical constraint condition.

  On the other hand, considering the specifications of the printer, in the draft mode where the carriage is driven at high speed, the discharge current value for realizing the printed image is often low, and conversely, it is somewhat In many cases, a decrease in throughput is acceptable.

  Therefore, by obtaining the total value of Icr and Ihead each time and adjusting the carriage drive waveform so as to satisfy Imax by lowering the acceleration value of Icr according to the print image, an example of an electrical error as shown in FIG. It is conceivable to avoid this.

  In general, in a printer on the premise that only constant speed printing is performed, the acceleration for driving the carriage cannot be reduced due to the limitation of the main body width. This has the relationship that acceleration is lowered => acceleration distance is increased, and such acceleration change may not be possible depending on the size of the device, for example.

  However, assuming that printing is performed during acceleration (deceleration), restrictions on the main body width can be ignored, and the carriage acceleration can be changed with only a slight decrease in throughput. By adjusting the carriage acceleration, the overall required current value can be adjusted, and a design that balances cost and performance in a well-balanced manner is possible.

  In the printing in the acceleration zone and the deceleration zone, of course, the ink ejection timing is controlled according to the current position of the carriage, and the control is performed so that inkjet recording is performed at the same resolution as in the constant speed printing zone. Nor.

  Consider the carriage drive current Icr. In the constant speed region (62), a current sufficient to balance the carriage mass and the steady load including friction flows, and in the acceleration (deceleration) region, a current for accelerating the carriage mass is added to the steady current value. . For estimation of the carriage drive current Icr in the acceleration region, the acceleration load in the acceleration region and the mechanical load that changes depending on the durability condition can be considered as the variation parameter.

  In general, this type of drive current is considered to increase in proportion to the maximum acceleration when considered in a simplified manner, and can be estimated in advance if a qualitative load change is applied in more strict control. it is conceivable that. Therefore, it is considered that an accurate value of Icr can be obtained by determining an initial value of Icr from a prior experiment and comparing the initial value with a current value for each drive.

  Next, the ejection current Ihead is considered. This is a current required to drive a number of nozzles provided in the print head in order to eject ink. For this reason, the necessary nozzles change depending on the print image and the print mode, and the required current changes accordingly. For example, when the speed priority mode or the recording medium is plain paper or the like and the ink discharge amount may be small, the discharge current Ihead is considered to be small. On the contrary, when the print area such as a photograph covers the entire area of the recording medium, it is considered that the discharge current Ihead increases because a large amount of discharge is required.

  Depending on the printing mode, switching to multi-pass printing may be performed, and ejection may be thinned out. Therefore, it is difficult to say that the above estimation is generally valid, but everything immediately before driving the carriage for printing in the sequence. Thus, it is not difficult to obtain the current amount (Ihead) for each carriage drive.

  In this embodiment, printing during acceleration and printing during deceleration are performed as described above, and the total current amount can be reduced by adjusting the acceleration in the acceleration section and the deceleration section. In this case, it is not necessary to increase the lateral width of the apparatus by extending the acceleration / deceleration section or reduce the width of the printable section by performing printing during acceleration and printing during deceleration.

  FIG. 7 is a diagram showing a carriage driving speed waveform profile and printing in this embodiment when printing during acceleration and printing during deceleration and control for adjusting acceleration in the acceleration zone and deceleration zone are performed as described above. The relationship between the ejection drive of the head, the change in carriage acceleration, and the amount of current is shown.

  In FIG. 7, the upper graph shows the carriage speed change, the middle graph shows the current (Icr) change, and the lower graph shows the total current amount, the element current amount (Icr, Ihead), and the allowable power source current amount (Imax). ing.

  In FIG. 7, the absolute value of acceleration is smaller in the carriage acceleration area 71 and the printing area 71 a and 73 a in the second half part and the head part of the carriage deceleration area 73 than in the carriage acceleration area 71 and other parts of the carriage deceleration area 73. It is controlled to become. As a result, the carriage drive current has a lower Icr value than the amount of current outside the print area. As a result, Icr + Ihead (carriage drive current + discharge current) can be made lower than the maximum current Imax that can be supplied by the power source, and recording control can be performed without exceeding the maximum current Imax in FIG.

  Further, in this embodiment, a recording medium conveyance system capable of double-sided recording as shown in FIG. 5 is assumed. In such a configuration, the basic control conditions of FIG. The current value for driving the roller is added and compared with Imax.

  At this time, as shown in FIG. 8, a necessary current value can be estimated from the feeding speed of each roller, the material of the recording medium to be conveyed, and the size information.

  That is, as shown in FIG. 8, the required current value for driving the transport roller is generally determined by the speed of the recording medium being transported, the material (thickness, size) of the recording medium, and the like. The required current increases as the conveyance speed increases, and the required current increases as the load increases as the thickness and size of the recording medium to be conveyed increase.

  These can be derived from an estimated curve obtained from a prior experiment or the like, and the required current value is summed every time before driving is started by multiplying the recording medium identification information (thickness, size) and the conveyance speed, and the basic of FIG. Addition is performed on each current value in the control. Thus, by adding a correction amount from the measured current value for each drive to the estimated curve, a more stable current amount can be estimated.

  Also, depending on the drive mode of the printer, the case where the conveyance drive itself is not performed (for example, when there is no double-sided printing), or the case where the conveyance drive itself is not executed depending on the timing of the print sequence can be considered. In this case, since the current value that can be distributed to Icr increases, it is possible to create a situation where the carriage can be driven while maintaining a high acceleration. In other words, it is possible to perform printing at the maximum printing speed with an inkjet printer that has more efficiently sorted the required current value.

  FIG. 9 shows an example of total current value control performed in the present embodiment based on the above-described concept of FIGS.

  FIG. 9 shows an example of final optimization control in this embodiment. The upper graph in FIG. 9 shows the carriage speed change and the speed change of the transport roller, paper feed roller, and double-sided roller, the center graph shows the current change, and the lower graph shows the total current amount, the element current amount, and the allowable power source current amount ( Imax).

  In the upper and middle graphs of FIG. 9, the thin solid line indicates the carriage drive, the thin dotted line indicates the transport roller, the thick solid line indicates the double-sided roller, and the thick dotted line indicates the drive current value of the paper feed roller. In the center graph, the carriage current amount is Icr, the discharge current amount is Ihead, the paper feed roller drive current amount is Ipreload, and the double-side roller drive current amount is Iduplex.

  In FIG. 9, two carriage drive sections are shown. The first drive (left side: acceleration section 91, constant speed section 92, deceleration section 93) and the second drive (right side: acceleration section 95, constant speed section). 96, the deceleration zone 97), in particular, whether or not the paper feed roller is driven. Also, the ejection current amount Ihead of the head is different between the first time and the second time (the first time is larger).

  In the second drive, it is confirmed that the total drive current amount does not exceed the maximum value Imax by performing the control described later based on various printing conditions, and the carriage drive profile control without acceleration control in the acceleration / deceleration section is performed as usual. Is selected.

  On the other hand, in the first drive, the later-described control is performed based on various printing conditions, and the carriage drive profile control for performing the acceleration control in the acceleration / deceleration section is selected so that the total drive current amount does not exceed the maximum value Imax. .

  In particular, the paper feed roller is driven only during the first carriage drive (Ipreload is added), and the double-sided roller drive is performed from the start to the end (Iduplex is added). The discharge current amount (Ihead) also shows a larger value in the first printing area.

  In FIG. 9, in the first drive control, Ihead and Ipreload (feed roller driving required current amount) may be large, and by reducing the carriage acceleration (absolute value thereof) in the print area 94a, Icr is reduced. Adjustment is made so that the total current falls below Imax.

  The hatched portion 98 in the lower part of FIG. 9 corresponds to the amount of current saved by this adjustment. If the acceleration control is not performed, the maximum current Imax will be exceeded if the total current amount before adjusting the carriage acceleration is added.

  On the other hand, in the second carriage drive, it is determined that the carriage acceleration can be driven at the maximum value from the stop of the feed roller drive and the decrease in Ihead due to the print image, so a drive profile that does not perform acceleration control is selected. The carriage operation linearly increases in speed, but the total current value is below the maximum current Imax.

  By performing the control as shown in FIG. 9 and adjusting the required current amount, the maximum current value that the power supply can accept can be reduced, and the influence on the printing speed (decrease in printing speed) can be alleviated to the maximum.

  FIG. 10 shows a configuration of a control circuit of the ink jet recording apparatus for performing the drive control as described above.

  In FIG. 10, reference numeral 1700 is an interface for inputting a recording signal, 1701 is an MPU, 1702 is a ROM for storing a control program executed by the MPU 1701, and 1703 is various data (such as the recording signal and recording data supplied to the head). This is a DRAM for storage.

  Reference numeral 1704 denotes a gate array (GA) that controls supply of recording data to the recording head 101, and also performs data transfer control among the interface 1700, MPU 1701, and RAM 1703.

  Reference numeral 105 is a carriage motor for conveying the recording head 101, 107 is a conveyance motor for conveying a recording medium, 125 is a paper feed motor, and 126 is a double-sided motor. Reference numeral 1705 denotes a head driver for driving the recording head 101, and 1706, 1707, 1708, and 1709 denote motor drivers for driving the carriage motor 105, the transport motor 107, the paper feed motor 125, and the double-sided motor 126, respectively.

  In the control circuit of FIG. 10, when a recording signal enters the interface 1700, the recording signal is converted into recording data for printing between the gate array 1704 and the MPU 1701. The motor drivers 1706 and 1707 are driven, and the recording head 101 is driven in accordance with the recording data sent to the head driver 1705 to perform recording.

  Here, the control program executed by the MPU 1701 is stored in the ROM 1702. However, an additional erasable / writeable storage medium such as an EEPROM is added, and the control program is changed from the host computer connected to the inkjet recording apparatus. You may comprise so that it can do.

  FIG. 11 shows the flow of the control flow performed at the top of the page to determine the initial drive mode when the printer is driven by the control circuit as shown in FIG. 10 in the ink jet recording apparatus as shown in FIGS. Yes. FIG. 1 shows the flow of processing for performing optimization control of carriage operation performed immediately before driving in each scan from the driving mode determined in the initial driving mode determination processing in FIG.

  In FIG. 11, when a print command is issued from the interface 1700 of FIG. 10, the subsequent processing is started. In the initial drive mode determination in step S15, initial drive conditions suitable for the print mode are determined. The determination for each scan in FIG. 1 is performed in accordance with the initial drive condition, and the final carriage drive condition is determined. In actual processing, each value is determined in the following procedure (steps S16 to S30). It will be decided.

  In a series of processes from step S15, first, in step S16, it is determined whether or not double-sided printing is performed based on a designated value of a print driver or the like. Here, when printing on the recording medium is designated as double-sided, the process proceeds to recording medium size determination in step S17, and when only single-sided printing is performed, the process proceeds to recording medium size determination in step S18.

  In the size determination in step S17 and step S18, the size information of the recording medium to be printed is acquired. The size information of the recording medium is acquired based on a designated value such as a print driver. A branch is made from the obtained recording medium size information to the conveyance sequence of the following control flow.

  In response to the result of the size determination in step S17, double-sided conveyance simultaneous drive determination is performed in step S19. This is based on the assumption that, depending on the size of the recording medium, a plurality of recording media cannot be simultaneously arranged in the paper conveyance path as shown in FIG. If this arrangement is possible, in other words, if the drive conditions are such that the recording medium that has finished printing is moved simultaneously with the recording medium that is currently printing, the total amount of current required to drive simultaneously with printing also increases. become. A double-sided conveyance driving speed DV1 for satisfying this electrical constraint condition is determined in the double-sided conveyance speed determination step S20.

  If there is no simultaneous driving during printing in step S19, it is not necessary to consider the discharge current amount, so the current limit for the double-sided roller becomes lighter. Accordingly, it is possible to set the conveyance speed to be increased so as to shorten the conveyance time. Therefore, the double-side conveyance speed DV2 is selected in the double-side conveyance driving speed determination step S21.

  In step S22 and step S23, it is determined whether or not to perform the preceding paper feeding of the next paper by driving the paper feed roller during printing in each state of step S19. Whether or not the preceding paper feeding is performed can be determined from the conveyance accuracy of the recording medium, electrical conditions, and the like that are known in advance. Here, when performing the preceding paper feeding, the driving speeds PV1 and PV2 for the preceding paper feeding are determined in the preceding paper feeding conveyance speed determination steps S25 and S26. Again, the driving speed for the preceding paper feeding is selected in consideration of the constraint condition for each recording medium, and when there is no problem of the conveyance accuracy, the maximum speed is selected as PV1 and PV2 within the range allowed by the power source. If the preceding paper feeding is not performed, the process proceeds to determination of the carriage driving speed in steps S28 and S29.

  In carriage drive speed determination steps S28 and S29, the carriage drive speeds CV1 and CV2 and the initial acceleration corresponding to the print mode (recording medium type, multi-pass) are determined. Since the initial drive conditions are met, actual printing is started.

  On the other hand, in response to the result of the recording medium size determination in step S18, whether or not the preceding paper feeding operation is possible is performed in step S24. When the preceding sheet feeding is performed, the preceding sheet conveying speed is determined in step S27, the preceding sheet conveying driving speed PV3 is determined, and then the process proceeds to step S30. Move on to step S30. In step S30, the carriage driving speed CV3 is obtained, and actual printing is performed after the initial driving conditions are met.

  As described above, in the initial drive mode determination process of FIG. 11, the power supply constraint conditions change depending on the presence / absence of double-sided printing, so the preceding paper feed speeds PV1, PV2, PV3 and carriage drive speeds CV1, CV2, CV3 are individually It is supposed to be. DV1 and DV2 are also individually determined based on the presence or absence of double-sided driving. These are parameters provided for more detailed determination.

  However, in a simpler configuration, only the change in carriage acceleration due to the print image takes into account the drive sequence against the addition amount under the condition that the load on all the transport motors is the heaviest (= the current amount is large). It is also conceivable to design the power supply based on the total amount of current within the range that can be handled. In this case, there is no speed restriction from the viewpoint of the total current amount, so the maximum speed within the range allowed by the conveyance accuracy is selected. For each initial value of CV1 = CV2 = CV3, PV1 = PV2 = PV3, DV1 = DV2, The final acceleration and speed of the carriage operation are determined from the determination for each scan.

  Subsequently, based on the driving conditions determined according to the control flow of FIG. 11, the current amount is estimated for each scan by the control of FIG. 1, and the final carriage driving conditions are determined.

  When the sequence is started by the carriage scan command, the ejection current amount Ihead in one scanning section is estimated by the ejection current determination in step S1. This Ihead is estimated according to the carriage position, and a comparison is made particularly with respect to the maximum current amount in the area where acceleration / deceleration printing is performed.

  In the CR drive motor current value determination in step S2, the carriage drive current amount Icr is estimated according to the drive conditions determined in steps S28, S29, and S30. In the estimation of Icr, an accurate estimated current amount can be obtained by performing a process of adding a correction amount learned during driving in addition to an estimation table determined by a prior experiment.

  In step S3, the recording medium is determined. Here, the size and thickness information of the recording medium with respect to the subsequent estimation of the current amount of the conveying roller is taken out.

  In step S4, it is determined whether or not the preceding sheet feeding is being performed (preceding sheet feeding determination). This is because, in addition to the case where the preceding sheet feeding itself is not performed in advance from FIG. 11, there is a case where the preceding sheet feeding cannot be started or ended due to the progress of the sequence. If the preceding paper feeding is being performed (or started during scanning), the current value of the preceding paper feeding drive motor is estimated in step S5, and Ipreload is estimated from the recording medium information and the driving conditions. The If there is no preceding paper feed, Ipreload = 0 is set in step S6.

  In the double-sided conveyance determination in step S7, it is determined whether or not double-sided conveyance is performed. This is because, in addition to the case where the double-sided conveyance itself is not performed in advance from FIG. 11, there is a case where the double-sided conveyance is not performed from the sequence or is completed. If the double-sided conveyance is being performed (or started during scanning), the current value of the double-sided conveyance drive motor is estimated in the double-sided conveyance drive motor current value determination step S8, and the recording medium information and drive are detected. From the condition, Iduplex is estimated. If there is no duplex conveyance here, Iduplex = 0 in step S9.

  In the used current value comparison in step S10, each estimated current amount is compared with the limited current amount. Specifically, the total current amount of Ihead + Icr + Ipreload + Iduplex is compared with the limit current amount Imax. If the total current amount is greater than Imax, a limit current error occurs in step S11, and the process proceeds to step S12.

  In step S12, the CR drive profile is changed and changed so that the acceleration value becomes smaller (CR drive profile change 1). From the acceleration lowered to a predetermined value, the carriage current amount Icrnew is estimated again, and the process proceeds to step S13.

  In step S13, the total current amount of Ihead + Icrnew + Ipreload + Iduplex is compared with the limit current amount Imax. If the total current amount is greater than Imax, a limit current error occurs, and the process proceeds to step S14.

  In step S14, the CR drive profile change (CR drive profile change 2) is performed again, and the drive target speed is changed so as to decrease until printing during acceleration is eliminated. This process is a process for controlling the deterioration of the throughput to the minimum by returning the acceleration to the initial condition to minimize the decrease in the drive target speed. A final carriage driving condition is determined with the driving profile at this time, and carriage driving is performed.

  If the limited current condition is satisfied in step S11 and step S13, there is no error, the final carriage driving condition is determined with the driving profile at each time point, and the carriage driving is performed based on this.

  As described above, by executing the series of controls shown in FIGS. 11 to 1, optimal carriage scanning and recording medium conveyance are executed.

  According to the present embodiment, on the premise that printing is performed during acceleration (deceleration), the carriage driving conditions are determined so that the optimum printing speed can be obtained within the electrical limitation.

  That is, the drive current required for driving each part of the printing mechanism is estimated according to the printing conditions, and the carriage drive profile is controlled according to the estimated drive current. In this carriage drive profile control, it is possible to control whether or not to perform ink ejection drive of the recording head in the acceleration section or the deceleration section of the carriage, and to control the carriage drive speed in the constant speed drive section of the carriage.

  To estimate the drive current required for driving the print mechanism, the print head drive current required for printing and the drive of the carriage drive mechanism required for printing are estimated according to the printing conditions. Reference can be made to the current, the drive current of the recording medium transport mechanism necessary for printing, and the like. Among these, the drive current of the recording medium transport mechanism can be estimated according to conditions such as whether or not to drive the recording medium transport means other than the sub-scanning drive system for carrying in the recording medium or duplex printing. Furthermore, in order to estimate the drive current required for driving the printing mechanism, it is possible to refer to printing conditions, particularly conditions such as the size or thickness of the designated recording medium.

  Then, the drive current required for driving each part of the printing mechanism is estimated according to the printing conditions, and the carriage drive profile is controlled according to the estimated drive current. In particular, the maximum current that can be supplied by the power supply unit is not exceeded. By controlling the carriage drive profile in this way, it is possible to perform print output as fast as possible without using a smaller power supply unit and without causing an overload of the power supply unit.

  That is, according to the present embodiment, even with a smaller power supply configuration, a printing operation with higher throughput than the conventional one can be performed even with a power supply unit that satisfies the required product specifications and has a particularly small capacity.

  In this embodiment, the recording mechanism provided with the double-sided conveyance mechanism as shown in FIGS. 4 and 5 is assumed. However, for example, even in a printer having a conveyance path in which the double-sided conveyance mechanism is omitted, the processing shown in FIGS. 1 and 11 can be performed, for example, with the double-sided drive determination portion omitted.

  Of course, in order to estimate the total amount of drive current required for driving the printing mechanism to be estimated, a drive current other than the drive means exemplified above may be used. For example, some printing apparatuses may be provided with a mechanism for applying a negative pressure to the back surface of the recording medium on the platen for suction. Items for estimating the amount of drive current required for such drive means are shown in FIG. In addition to the processing shown in FIG.

  In the above-described embodiment, the description has focused on the drive profile control particularly in the acceleration / deceleration region (or constant speed drive region) of the carriage where printing is performed. However, the method of this embodiment controls the acceleration outside the print region. Of course, the present invention can be applied to the case of adjusting the amount of current.

  The present invention can be implemented in various image forming apparatuses using a serial scan method. A control program for implementing the present invention can be stored in advance in a storage medium such as a ROM or a hard disk of the image forming apparatus. Further, for example, it is possible to install / update from a medium such as an MO or a CD-ROM connected by a USB interface or the like. When the host interface is a network interface, it can be supplied from an arbitrary server via the network.

It is the flowchart figure which showed the flow of the carriage drive control by this invention. It is the perspective view which showed the structure of the recording mechanism of a general inkjet recording device. It is explanatory drawing which showed the carriage drive profile in a common inkjet recording device. It is explanatory drawing which showed the double-sided conveyance mechanism in an inkjet recording device. It is explanatory drawing which showed the mode of the double-sided conveyance in an inkjet recording device. It is explanatory drawing which showed an example of the carriage drive profile of printing during acceleration (deceleration). It is explanatory drawing which showed an example of the carriage drive profile in the case of performing acceleration control during printing during acceleration (deceleration). It is explanatory drawing which showed the change of the conveyance current according to the thickness of a recording medium, and a magnitude | size. It is explanatory drawing which showed an example of the carriage drive control by this invention. It is the block diagram which showed the structure of the control circuit which can implement the carriage drive control by this invention. It is the flowchart figure which showed the flow of the carriage drive mode initialization control by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Recording head 102 Carriage 103 Guide shaft 104 Belt 105 Drive motor 106 Paper supply base 107 Paper conveyance motor 108 Motor gear 109 Conveyance roller gear 110 Conveyance roller 111 Pinch roller 114 Chassis 115 Recording paper 116 Rotary encoder film 117 Encoder sensor 118 Feed roller 119 Double-sided roller 120 Paper feed cassette 121 Recording medium 122 Recording medium (1)
123 Recording medium (2)
124 recording media (3)
1700 interface 1701 MPU
1702 ROM
1703 DRAM
1704 GA
1705 Head Driver 1706 Motor Driver 1707 Motor Driver 1708 Motor Driver 1709 Motor Driver

Claims (9)

A carriage on which a recording head that discharges ink from an ink discharge portion to record the recording medium is mounted; a carriage drive mechanism that transports the carriage along the recording medium; and a recording medium transport mechanism that transports the recording medium In a control method of a printing apparatus having a printing mechanism,
A carriage drive profile control step of estimating a drive current required for driving the printing mechanism according to printing conditions and controlling a profile of carriage drive performed by the carriage drive mechanism according to the estimated drive current. A control method for a printing apparatus.   The printing apparatus control method according to claim 1, wherein in the carriage drive profile control process, a drive current necessary for driving the printing mechanism is estimated according to a printing condition, and the drive current is estimated according to the estimated drive current. A control method for a printing apparatus, comprising: controlling whether or not to perform ink ejection driving of the recording head in an acceleration section or a deceleration section of a carriage.   The printing apparatus control method according to claim 1, wherein in the carriage drive profile control process, a drive current necessary for driving the printing mechanism is estimated according to a printing condition, and the drive current is estimated according to the estimated drive current. A method for controlling a printing apparatus, comprising: controlling a carriage driving speed in a constant speed driving section of a carriage.   2. The method for controlling a printing apparatus according to claim 1, wherein a recording head driving current is estimated from an ink discharge amount of the recording head required for printing according to the printing conditions, and is necessary for driving the printing mechanism based on the estimated recording head driving current. A control method for a printing apparatus, characterized in that a correct driving current is estimated.   The method for controlling a printing apparatus according to claim 1, wherein a driving current of the carriage driving mechanism necessary for printing is estimated according to the printing condition, and a driving current necessary for driving the printing mechanism is estimated based on the estimated driving current. A control method for a printing apparatus.   The control method of the printing apparatus according to claim 1, wherein a driving current of the recording medium transport mechanism necessary for printing is estimated according to the printing condition, and a driving current necessary for driving the printing mechanism is calculated based on the estimated driving current. A control method of a printing apparatus, characterized by estimating.   7. The control method for a printing apparatus according to claim 6, wherein a driving current of the recording medium transport mechanism necessary for printing is estimated according to a size or thickness of the recording medium designated by the printing conditions, and based on the estimated driving current A method for controlling a printing apparatus, comprising: estimating a driving current required for driving a printing mechanism.   A printing apparatus control program for controlling a printing mechanism including the carriage, the carriage driving mechanism, and the recording medium conveying mechanism of the printing apparatus to implement the printing apparatus control method according to claim 1. .   8. A printing apparatus, comprising: a printing mechanism including the carriage, the carriage driving mechanism, and the recording medium conveying mechanism, which implements the printing apparatus control method according to claim 1.

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