JP6303590B2 - Printing device - Google Patents

Description

  The present invention relates to a printing apparatus that feeds a print medium to a printable position.

  For example, Patent Document 1 discloses a printing apparatus that performs control to decelerate driving of a conveyance roller when a large load applied to a motor that is a power source of the conveyance roller is detected in the process of feeding a print medium (for example, paper). ing. Further, in this printing apparatus, assuming that a skew (skew) in which the print medium is fed obliquely occurs, a skew removing operation for removing the skew is performed during the feeding. In general, the printing apparatus is configured to forcibly stop the driving of the motor as an abnormality such as a paper jam has occurred when the load of the motor exceeds a threshold value during paper feeding and conveyance. Yes.

JP 2009-181116 A

  By the way, in the printing apparatus, when the skew removal operation is performed during the feeding operation, a relatively large load may be generated on the motor due to the skew removal operation. If the load exceeds the threshold, it is not a paper jam but a load for normal skew removal operation, but the drive of the motor is forcibly mistaken for the skew removal load as a print media jam. There is a problem of being stopped. In this case, the printing medium feeding operation is interrupted in the middle of the skew removing operation, and the operation cannot be shifted to the next operation, and it is necessary to redo the operation for executing printing.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a printing apparatus that can shift to the next operation after the skew removal operation even if the motor load increases during the skew removal operation. It is to provide.

Hereinafter, means for solving the above-described problems and the effects thereof will be described.
A printing apparatus that solves the above-described problem includes a feeding mechanism that feeds a printing medium, a motor that is a power source that drives the feeding mechanism, and a control unit that drives and controls the motor. Controls the motor to cause the feeding mechanism to perform a skew removing operation for removing the skew of the printing medium during feeding of the printing medium, and the load of the motor during the skew removing operation causes the skew of the printing medium to be skewed. If the condition indicating that is removed is satisfied, the skew removal operation is terminated and the operation proceeds to the next operation.

According to this configuration, if the load of the motor satisfies the condition indicating that the skew of the printing medium has been removed during the skew removal operation, the skew removal operation is terminated and the operation proceeds to the next operation. Therefore, since it is possible to shift to the next operation without waiting for the end of the skew removal operation, the time required for the printing medium feeding operation can be shortened.
A printing apparatus that solves the above problems includes a feeding roller that feeds a printing medium, a pair of conveying rollers provided downstream of the feeding roller in the conveying direction of the printing medium, and a power source for the feeding roller. A first motor that serves as a power source for the pair of transport rollers, and a control unit that controls the first motor and the second motor, wherein the control unit skews the printing medium. The skew removal operation for removing the image is performed by driving one or both of the first motor and the second motor, and during the skew removal operation, the first motor and the second motor are driven. If the load on the motor satisfies the condition indicating that the skew of the print medium has been removed, or the drive amount of the motor exceeds the set amount, the skew removal operation is terminated and the next operation Migrate.
A printing apparatus that solves the above problems includes a feeding roller that feeds a printing medium, a pair of conveying rollers provided downstream of the feeding roller in the conveying direction of the printing medium, and a power source for the feeding roller. A first motor, a second motor serving as a power source for the transport roller pair, and a control unit that controls the first motor and the second motor, the control unit including the feeding roller, After the biting operation for conveying the print medium forwardly from the pair of conveyance rollers to a position protruding to the downstream side in the conveyance direction by rotating both the conveyance roller pair forward, the feeding roller is stopped as a skew removal operation. The transport roller pair is reversely rotated to discharge the print medium upstream in the transport direction, and the load on the second motor increases during the skew removal operation. When it is detected that descends after, to end the skew removal operation to shift to the next operation.
A printing apparatus that solves the above problem includes a battery, a feeding mechanism that feeds a printing medium, a motor that is a power source that drives the feeding mechanism, and a control unit that controls the driving of the motor. The feeding mechanism includes a feeding roller that feeds a print medium, and a pair of transport rollers provided on the downstream side of the feed roller in the transport direction of the print medium, and the motor is powered by the power of the battery. When driving, after the biting operation of rotating both the feeding roller and the transport roller pair forward to transport the print medium from the transport roller pair to a position protruding downstream in the transport direction, the printing is performed. As a skew removing operation for removing the skew of the medium, the discharge that discharges the print medium upstream in the transport direction by reversing the pair of transport rollers while the feeding roller is stopped. To perform the operation, satisfies a condition indicating that the load of the motor during the skew correction operation skew of the print medium is removed, exit the skew operation proceeds to the next operation.
A printing apparatus that solves the above problem drives a first power supply unit that supplies power from a commercial power supply, a second power supply unit that includes a battery, a feeding mechanism that feeds a printing medium, and the feeding mechanism. A motor serving as a power source; and a control unit that drives and controls the motor, and the control unit performs a skew removal operation for driving and controlling the motor to remove skew of the print medium, and performs the skew removal operation. When the load of the motor exceeds a threshold value, the process proceeds to the next operation, and when the motor is driven by the power of the second power supply unit, compared with the case of driving the motor by the power of the first power supply unit, The driving speed of the motor is made lower and the threshold value is made smaller.

A printing apparatus that solves the above problems includes a first power supply unit that supplies power from a commercial power supply, a second power supply unit that includes a battery, a feed roller that feeds a print medium, and printing from the feed roller. A pair of transport rollers provided on the downstream side in the transport direction of the medium, a first motor that is a power source of the feeding roller, a second motor that is a power source of the pair of transport rollers, the first motor, and the A control unit that controls a second motor, wherein the control unit drives both the first motor and the second motor to perform a skew removing operation, and uses the power supplied from the first power supply unit to In the first mode for driving the first and second motors, if the load of the first motor exceeds a threshold during the skew removal operation, the operation proceeds to the next operation, and the supply of the second power supply unit is performed. Said power by power And if a second mode for driving the second motor, the sum of the load of the load of the first motor the second motor After exceeds the threshold value, the process proceeds to the next operation.
A printing apparatus that solves the above problems includes a first power supply unit that supplies power from a commercial power supply, a second power supply unit that includes a battery, a feed roller that feeds a print medium, and printing from the feed roller. A pair of transport rollers provided on the downstream side in the transport direction of the medium, a first motor that is a power source of the feeding roller, a second motor that is a power source of the pair of transport rollers, the first motor, and the A control unit that controls a second motor, wherein the control unit is in a first mode in which the first and second motors are driven by power supplied from the first power supply unit; In the second mode in which the first skew removing operation for driving both the second motor and the second motor is performed and the first and second motors are driven by the power supplied from the second power supply unit, the first motor is used. And the second A second skew removal operation for driving the other motor with one of the motors stopped is performed, and the first motor and the second motor are driven during the skew removal operation. If the load of the motor satisfies the condition indicating that the skew of the print medium has been removed, the skew removal operation is terminated and the operation proceeds to the next operation.
A printing apparatus that solves the above problems includes a feeding roller that feeds a printing medium, a pair of conveying rollers provided downstream of the feeding roller in the conveying direction of the printing medium, and a power source for the feeding roller. A first motor that serves as a power source for the pair of transport rollers, and a control unit that controls the first motor and the second motor, wherein the control unit skews the printing medium. A skew removal operation is performed by driving one or both of the first motor and the second motor, and a first mode in which a feeding speed of the print medium is a first feeding speed; There is a second mode that is a second feeding speed that is lower than one feeding speed, and the control unit, when in the first mode, performs the first motor and the second motor during the skew removal operation. Tono When the load of the driven motor exceeds the first threshold value, the operation proceeds to the next operation, and in the second mode, the motor that is driven out of the first motor and the second motor during the skew removal operation. When the load exceeds the second threshold value smaller than the first threshold value, the next operation is started.
A printing apparatus that solves the above problems includes a feeding roller that feeds a printing medium, a pair of conveying rollers provided downstream of the feeding roller in the conveying direction of the printing medium, and a power source for the feeding roller. A first motor that serves as a power source for the pair of transport rollers, and a control unit that controls the first motor and the second motor, wherein the control unit skews the printing medium. A skew removing operation for removing the first and second motors is performed by driving one or both of the first motor and the second motor, and the control unit performs the first motor and the second motor during the skew removing operation. When the load of the motor to be driven exceeds a threshold value, the skew removal operation is terminated and the operation proceeds to the next operation, and the threshold value indicates that the medium size of the print medium is the first medium size. Is a first threshold value, wherein when the large second medium in size than the first medium size is larger second threshold value than the first threshold value.
In the printing apparatus, it is preferable that the control unit shifts to the next operation when the load of the motor exceeds a threshold value during the skew removal operation as the condition.
According to this configuration, when the load on the motor exceeds the threshold during the skew removal operation, the next operation is performed. Therefore, the next operation can be performed as soon as the skew is obtained without waiting for the end of the skew removal operation. This is effective during a skew removal operation in which the motor load increases after the removal of the skew. For example, when the skew removal operation is a reverse abutting operation in which the print medium is abutted against a pair of conveying rollers that reversely rotate the print medium, the operation can be shifted to the next operation as soon as the skew is removed.

  In the printing apparatus, it is preferable that the control unit shifts to the next operation when the controller detects that the load of the motor has dropped after being raised during the skew removing operation.

  According to this configuration, when it is detected that the motor load has increased and then decreased during the skew removal operation, the operation proceeds to the next operation, and as soon as the skew is obtained without waiting for the end of the skew removal operation, Move to the next operation. This is effective in a skew removing operation in which the motor load is large while the skew is removed and the motor load is reduced after the skew is removed. For example, after skewing operation in which the print medium is sandwiched between the transport roller pair and protruding by a predetermined amount in the transport direction, the transport roller pair is reversed to discharge the print medium upstream in the transport direction. When the load of the motor that has risen in the course of operation falls after discharging, the operation proceeds to the next operation. For this reason, it is possible to shift to the next operation as soon as the skew due to ejection is obtained without waiting for the end of the skew removal operation.

In the printing apparatus, in the skew removing operation, it is preferable that the skew removing operation is terminated and the operation proceeds to the next operation when the driving amount of the motor exceeds a set amount.
According to this configuration, even if the motor load does not exceed the threshold during the skew removal operation, the skew removal operation can be terminated and the next operation can be started if the motor drive amount exceeds the set amount. For example, it is possible to avoid the inconvenience that it is not possible to shift to the next operation because the motor load does not exceed the threshold during the skew removal operation.

  In the printing apparatus, it is preferable that the control unit stops the driving of the motor as an abnormality when the load of the motor exceeds a threshold value in the next operation after the skew removing operation.

  According to this configuration, even if the load of the motor at the time of the skew removal operation satisfies the condition and the operation is shifted to the next operation, if an abnormality such as a jam of the print medium has occurred, the motor is driven as an abnormality. Can be stopped. In the next operation after the skew removal operation, the increase in the motor load is not caused by the skew removal operation. Therefore, the drive of the motor is stopped by specifying that it is caused by an abnormality such as a jam of the print medium. be able to. For example, even when the motor load exceeds a threshold value and shifts to the next operation due to a jam of the print medium during the skew removal operation, the drive of the motor can be stopped as an abnormality.

  In the printing apparatus, a battery is provided as a power supply unit, and the feeding mechanism includes a feeding roller and a pair of conveyance rollers provided on the downstream side in the conveyance direction of the print medium with respect to the feeding roller, and the motor Is driven by the battery power, the skew removal is performed after the biting operation in which both the feeding roller and the transport roller pair are rotated forward to transport the print medium to a position sandwiched between the transport roller pair. As an operation, it is preferable to perform a discharge operation of discharging the print medium upstream in the transport direction by reversing the pair of transport rollers while the feeding roller is stopped.

  According to this configuration, when the motor is driven by the power of the battery (that is, in the battery mode), the discharging operation is the operation of reversing the conveying roller pair under the stopped state of the feeding roller. Compared to the configuration in which the skew removal operation is performed to rotate both the conveyance roller pairs, the print medium can be skewed while suppressing the power consumption of the motor.

  In the printing apparatus, the power supply unit includes a first power supply unit that supplies power from a commercial power supply and a second power supply unit that includes a battery, and when the motor is driven by the power of the second power supply unit, It is preferable that the driving speed of the motor is made lower and the threshold value is made smaller than when driving with the power of the first power supply unit.

  According to this configuration, when driven by the power supplied from the battery (in the battery mode), the motor is driven at a lower speed and a smaller threshold is used than when driven by the power supplied from the first power supply unit. . Therefore, the situation where the power consumption of the motor exceeds the power supplied by the battery can be reduced, and even in the battery mode, it is possible to perform the skew removal operation of the print medium without incurring a system down due to power shortage as much as possible.

  In the printing apparatus, the power supply unit includes a first power supply unit that supplies power from a commercial power supply, and a second power supply unit that includes a battery. The feeding mechanism includes a feeding roller and the feeding roller. And a pair of transport rollers provided on the downstream side in the transport direction of the print medium, the motor being a first motor that is a power source for the feed roller and a second motor that is a power source for the pair of transport rollers The first motor and the second motor are driven to perform a skew removing operation, and the control unit drives the motor with the power supplied from the first power supply unit. When in the mode, the load of the first motor is used as the load of the motor. When the mode is the second mode of driving the motor with the power supplied from the second power supply unit, the load of the motor is used. , It is preferable to use the sum of the load of the second motor and the load of the first motor.

  According to this configuration, when the control unit is in the first mode in which the motor is driven by the power supplied from the first power supply unit, the load of the first motor is used as the load of the motor. Further, in the second mode in which the motor is driven by the power supplied from the second power supply unit, the sum of the load of the first motor and the load of the second motor is used as the motor load. Therefore, in the first mode, where the power supplied to the power supply unit is relatively large and the motor power consumption is relatively low even if both motors are driven simultaneously, only the load on the first motor is used. In the second mode, when the motors are driven at the same time when the motors are driven at the same time, the power consumption of the power supply unit is relatively small. Since the sum of the load of the motor and the load of the second motor is used, it is easy to avoid a system down that occurs when the motor power consumption exceeds the supply power.

  In the printing apparatus, the power supply unit includes a first power supply unit that supplies power from a commercial power supply, and a second power supply unit that includes a battery. The feeding mechanism includes a feeding roller and the feeding roller. And a pair of transport rollers provided on the downstream side in the transport direction of the print medium, the motor being a first motor that is a power source for the feed roller and a second motor that is a power source for the pair of transport rollers And the controller is configured to drive both the first motor and the second motor in the first mode in which the motor is driven by the power supplied from the first power source. In the second mode in which the skew removal operation of 1 is performed and the motor is driven by the power supplied from the second power supply unit, one of the first motor and the second motor is stopped. It is preferred to carry out the second skew operation for driving the other motor.

  According to this configuration, in the first mode in which the power supplied from the first power supply unit is relatively large and the motor power consumption is relatively less likely to exceed the power supplied even if the first motor and the second motor are driven simultaneously. A first skew removal operation for driving both the first motor and the second motor is performed. On the other hand, if the power supplied to the second power supply unit is relatively small and both motors are driven at the same time, in the second mode where the motor power consumption is likely to exceed the power supplied to the second power supply unit, the first motor And the second motor, the second skew removing operation for driving the other motor in a state where one motor is stopped is performed. Therefore, it is easy to avoid a system down that occurs when the motor power consumption exceeds the power supply, regardless of whether the power supply unit that supplies power to the motor is the first power supply unit or the second power supply unit.

In the printing apparatus, it is preferable that the threshold value changes according to at least one of a printing mode, a power supply mode, and medium information regarding the printing medium.
According to this configuration, the threshold value changes according to at least one of the print mode, the power supply mode, and the medium information related to the print medium, so that it is possible to shift to the next operation at an appropriate timing from which the skew has been removed. For example, the printing medium feeding speed differs depending on the printing mode, and the higher the feeding speed, the greater the load on the motor at the time of skew removal. Therefore, it is preferable to set the threshold value accordingly. In this case, even if the feeding speed of the printing medium differs depending on the printing mode, it is possible to shift to the next operation at an appropriate timing after the skew is removed. Further, for example, since the power supplied to the power supply unit varies depending on the power supply mode, it is preferable to set the threshold value so that the total power consumption of the printing apparatus including the power consumption of the motor does not exceed the power supplied to the power supply unit. In this case, even if the power supplied by the power supply unit differs depending on the power supply mode, the next operation can be performed at an appropriate timing from which the skew is removed while avoiding a system down. Further, for example, at the time of feeding due to the fact that the friction coefficient of the printing medium with respect to the feeding mechanism is different depending on the medium information about the printing medium (at least one of medium type (for example, paper type) and medium size (for example, paper size)). Since the frictional resistance force that the feeding mechanism receives from the print medium is different and the load on the motor is different, it is preferable to set the threshold value higher as the friction coefficient of the printing medium against the feeding mechanism is higher. In this case, even if the load on the motor is different due to the frictional resistance that the feeding mechanism receives from the print medium depending on the type of the print medium, it is possible to shift to the next operation at an appropriate timing after the skew is removed.

The perspective view which shows a printer. FIG. 2 is a schematic perspective view showing the printer in a state where an exterior cover is removed. (A), (b) is a schematic side view explaining operation | movement of an automatic feeding apparatus. The graph which shows the feeding speed profile of each power mode. (A) is a schematic side view for explaining the skew-removing operation of the reverse contact method, (b) is also a schematic plan view, (c) is a schematic side view for explaining the cueing operation, and (d) is also a schematic plan view. . (A), (c) is a schematic side view explaining the skew removal operation | movement of a biting discharge system, (b), (d) is each schematic plan view. FIG. 3 is a block diagram illustrating an electrical configuration of the printer. The block diagram which shows the function structure of a computer. (A)-(c) is a schematic top view which shows the feeding operation | movement of a reverse contact type. (A) is a graph which shows the change of the load of a feeding motor in each process of a reverse rotation abutting system, (b) is a graph which similarly shows the change of the skew amount of the paper in each process. (A)-(c) is a schematic top view which shows the feeding operation of a biting discharge system. (A) is a graph which shows the change of the load of the conveyance motor in each process of a biting discharge system, (b) is a graph which similarly shows the change of the skew amount of the paper in each process. The flowchart which shows a feeding control program.

Hereinafter, an embodiment embodied in a printer which is an example of a printing apparatus will be described with reference to the drawings.
As shown in FIG. 1, the printer 11 is a mobile inkjet color printer as an example. On the front surface (right surface in FIG. 1) of the apparatus main body 12 having a thin and substantially rectangular parallelepiped shape, an operation panel 13 used by the user for input operation and the like is provided. The operation panel 13 is provided with a display unit 14 made of, for example, a liquid crystal panel and an operation unit 15 made up of a plurality of operation switches. The operation unit 15 includes a power switch 15 a, a selection switch 15 b and a cancel switch 15 c that are operated when a desired item is selected on the menu screen of the display unit 14. Note that at least a part of the operation panel 13 may be provided on the upper surface of the apparatus main body 12 in order to reduce the thickness thereof, or may be a storage type or a folding type that can be stored in the apparatus main body 12 when not in use. Further, the display unit 14 may be externally connected to the apparatus body 12 via a connector.

  As shown in FIG. 1, an automatic feeding device 17 having a feeding tray 16 that can be set in a state where the paper P is positioned in the width direction by a pair of edge guides 16 a is provided on the back surface of the apparatus main body 12. ing. The automatic feeding device 17 includes a roll paper feeding method in which roll paper set outside or inside the apparatus main body 12 is fed and fed, or a feeding cassette containing a plurality of sheets is provided in the apparatus main body 12. A cassette feeding system in which one or more are detachably mounted and the sheets are fed one by one from the sheet group in the feeding cassette may be used.

  As shown in FIG. 1, a carriage 21 is provided in the apparatus main body 12 so as to be reciprocally movable in the scanning direction X while being guided by a guide shaft 22. A recording head 23 is attached to the lower portion of the carriage 21. The automatic paper feeder 17 feeds the paper P to a position where recording by the recording head 23 is possible. As the carriage 21 moves in the scanning direction X, ink droplets are ejected from the recording head 23, whereby printing for one scan is performed on the paper P. The paper P intersects the scanning direction X between each scan. It is conveyed to the next scanning position in the conveyance direction Y. In this way, the scanning of the carriage 21 and the conveyance of the paper P are performed approximately alternately, whereby a document, an image, or the like is printed on the paper P. The printed paper P discharged from the discharge port 12a on the front surface of the apparatus main body 12 is stacked on a slide-type discharge stacker 24 (discharge tray) that has been extended.

  In addition, a USB port 25, a card slot 26, and a wireless LAN interface (not shown) (for example, “Wi-Fi” (registered trademark)) are provided at the front side end portion of the apparatus main body 12 (right end portion as an example in FIG. Is provided. Image data or the like is read from an external storage device (for example, USB memory) connected to the USB port 25 or a memory card connected to the card slot 26, or a portable host device (smartphone or mobile phone) via a wireless LAN interface. Image data or the like can be received wirelessly, and the printer 11 can print the image or the like.

  Further, the apparatus main body 12 has a power jack (not shown) that can be connected to an output terminal (power supply plug) of an AC adapter 27 having a power plug 27a that can be plugged into an outlet of a commercial AC power supply 30 (see FIG. 7). ) Is provided. The AC adapter 27 supplies power to the printer 11 with a predetermined voltage obtained by converting AC from the commercial AC power supply 30 into DC. Further, a battery 28 is accommodated in the apparatus main body 12 as a power source that can be used when the printer 11 is carried. The battery 28 of the present embodiment is a small battery with a relatively small capacity in order to reduce the size of the printer. For this reason, the power Wb (battery supply power) that can be supplied by the battery 28 is smaller than the power Wac (AC power supply power) that can be supplied via the AC adapter 27 (Wb <Wac). Of course, although the battery 28 is a little larger, the battery supply power Wb having the same value as the AC power supply power Wac by the AC adapter 27 may be output.

  Next, the internal configuration of the printer 11 will be described with reference to FIG. As shown in FIG. 2, in the printer 11, the carriage 21 is placed in the scanning direction X on the guide shaft 22 installed between the left and right side walls in FIG. Are provided so as to be capable of reciprocating. An endless timing belt 34 is wound around a pair of pulleys 33 attached to the inner surface of the back plate of the main body frame 31, and the carriage 21 is fixed to a part of the timing belt 34. The pulley 33 on the right side in FIG. 2 is connected to the drive shaft (output shaft) of the carriage motor 35, and the carriage 21 scans via a timing belt 34 that rotates forward or backward as the carriage motor 35 is driven forward or backward. Reciprocate in direction X.

  A plurality of (for example, four) ink cartridges 37 each containing four color inks of black (K), cyan (C), magenta (M), and yellow (Y), for example, are loaded on the carriage 21. Has been. The ink supplied from each ink cartridge 37 is ejected from a nozzle group for each ink color that opens on the lower surface of the recording head 23. Further, below the movement path of the carriage 21, a support base 38 that defines an interval (gap) between the recording head 23 and the paper P is provided so as to extend along the scanning direction X. The ink colors that can be ejected by the recording head 23 are not limited to four colors, and may be three colors, five to eight colors, or one black color.

  The main body frame 31 is provided with a linear encoder 39 that outputs a number of pulses proportional to the amount of movement of the carriage 21 so as to extend along the movement path of the carriage 21. In the printer 11, in addition to position control and speed control of the carriage 21, ink ejection timing control of the recording head 23 is performed based on the pulse signal output from the linear encoder 39.

  Further, the feeding motor 41 provided at the lower right end of the main body frame 31 in FIG. 2 is a power source of the automatic feeding device 17. By rotating a feed roller (not shown) by the power of the feed motor 41, a plurality of sheets P set on the feed tray 16 (see FIG. 1) are fed one by one. The conveyance motor 42 provided in the vicinity of the feeding motor 41 is a power source for the conveyance roller pair 43 and the discharge roller pair 44 provided on the upstream side and the downstream side of the support base 38 in the conveyance direction Y, respectively. . Each of the roller pairs 43 and 44 includes drive rollers 43a and 44a that are rotationally driven by the power of the transport motor 42, and driven rollers 43b and 44b that rotate in contact with the drive rollers 43a and 44a, respectively. The paper P is transported in the transport direction Y while being sandwiched (niped) in the transport direction Y by two roller pairs 43 and 44.

  In the serial type printer 11, a printing operation in which ink is ejected from the recording head 23 onto the paper P during the scanning of the carriage 21 and recording for one scan is performed, and a transporting operation in which the paper P is transported to the next recording position. By repeating substantially alternately, a document, an image, or the like is printed on the paper P. In addition, instead of the configuration in which the feeding motor 41 of the feeding system and the conveying motor 42 of the conveying system are separately provided, a configuration in which one motor common to the feeding system and the conveying system is provided may be employed.

  In FIG. 2, one end position (right end position in FIG. 2) on the movement path of the carriage 21 is a home position (home position) where the carriage 21 stands by when not printing. A maintenance device 45 that performs maintenance of the recording head 23 is disposed immediately below the carriage 21 disposed at the home position. In the present embodiment, the transport motor 42 is also a power source for the maintenance device 45.

  As shown in FIG. 3, a hopper 18 is supported on the upper surface side of the feeding tray 16 disposed obliquely on the back surface of the main body so as to be tiltable within a predetermined angle range about an upper end shaft 18a. Yes. The hopper 18 is urged in a direction away from the feed tray 16 (upper left direction in FIG. 3) by a compression spring 19 interposed between the hopper 18 and the feed tray 16. Near the lower end of the hopper 18, a feeding roller 20 is arranged in a state that allows rotation around a rotating shaft 20 a. The hopper 18 is shown in FIG. 3A where the paper set on its upper surface is separated from the feeding roller 20 and in FIG. 3B where the set paper can contact the feeding roller 20. Reciprocates between feeding positions.

  A guide portion 16b that guides the paper P when the feeding roller 20 feeds is provided at a position facing the feeding roller 20 on the upper surface of the end of the feeding tray 16 on the downstream side in the paper feeding direction (left side in FIG. 3). Is provided. Further, a retard roller 46 is disposed at a position facing the feed roller 20 in the vicinity of the guide portion 16b. The retard roller 46 is provided so as to be driven and rotated with respect to the feeding roller 20 in a state where a constant rotational load is applied by a torque limiting mechanism such as a torque limiter. The hopper 18 and the retard roller 46 operate in conjunction with each other. When the hopper 18 is disposed at the feeding position shown in FIG. 3B, the retard roller 46 is disposed at a position close to the feeding roller 20 and is fed. The sheet P to be fed is sandwiched between the feeding roller 20 and the retard roller 46. The automatic feeding device 17 is provided with a paper presence sensor 47 that detects the presence or absence of the paper P on the hopper 18.

  As shown in FIG. 3B, when the feeding roller 20 rotates in the clockwise direction in the state where the hopper 18 is moved up to the feeding position, the uppermost sheet P of the paper P is moved by the retard roller 46. The paper is fed downstream in the feeding direction while being separated from other sheets.

  As shown in FIGS. 3A and 3B, a paper detection sensor 48 capable of detecting the paper P on the feed path is provided at a position between the feed roller 20 and the transport roller pair 43. Yes. The paper detection sensor 48 includes a lever 48a whose lower end extends to reach the paper conveyance path, and an optical sensor unit 48b whose detection target is the upper end of the lever 48a. In the state where there is no paper P in the detection area of the paper detection sensor 48, the lever 48a is returned to the original position shown in FIG. 3A by the biasing force of a spring (not shown) and turned off. When the tip of P pushes the lower end of the lever 48a and tilts it as shown in FIG. In the printer 11, the position of the paper P in the transport direction Y is managed based on the paper position when the paper detection sensor 48 detects the leading edge of the paper P and is turned on (for example, the origin). The paper P is fed until the leading edge reaches the print start position by the recording head 23. In the middle of this feeding operation, a skew removing operation, which will be described later, is performed in order to remove skew (skew) in which the paper P is inclined with respect to the transport path.

  A paper width sensor 49 is provided in the carriage 21 at a position upstream of the recording head 23 in the transport direction Y. The paper width sensor 49 is an optical sensor that receives the reflected light of the light emitted toward the support base 38, and the paper P fed by the carriage 21 waiting at the position where the paper P is fed. It is possible to detect the leading edge of the paper P or to detect the side edge of the paper P in the scanning direction X (width direction) when the carriage 21 moves in the scanning direction X. Note that the retard roller 46 and the hopper 18 are held at the feeding position shown in FIG. 3B and fed while the next page to be fed next exists when the heading of the paper P is finished. Return to the retreat position when there is no next page.

  Next, for the skew removal performed in the middle of the feeding process in order to remove the skew (skew) in which the paper P is inclined obliquely with respect to the transport path, the “reverse abutting method” and the “biting discharge method” are used. There are two main types. Hereinafter, these skew removal methods will be described in order. First, with reference to FIG. 5, the feeding operation of the reverse contact method will be described. The feeding operation of the reverse contact method includes a skew removing operation shown in FIGS. 5A and 5B and a cueing operation shown in FIGS. 5C and 5D.

  As shown in FIGS. 5A and 5B, the paper P is fed by rotating the feeding motor 41 in the normal rotation direction which is the paper feeding direction and rotating the feeding roller 20 in the normal rotation direction. Feed along the route. Before the leading edge of the paper P reaches the transport roller pair 43, the transport motor 42 is driven in reverse so that the transport roller pair 43 is rotated in a direction opposite to the direction during transport of the paper P. As a result, as shown in FIGS. 5A and 5B, the leading end in the transport direction of the paper P is abutted against the reversely rotating transport roller pair 43, and the leading end side is in the axial direction of the transport roller pair 43. By being parallel, the skew with respect to the transport direction Y is eliminated. That is, as shown in FIG. 5B, the skewed sheet P is abutted against a pair of conveying rollers 43 whose front corners are rotated in reverse, and the sheet P is a solid line arrow with the corners being abutted as fulcrums. , The skew of the paper P is removed as indicated by a two-dot chain line in FIG.

  In this reverse abutting operation, the sheet P rotates around the corner from the corner of the leading edge of the sheet P skewed with the assumed maximum skew amount against the conveying roller pair 43. This is performed for a predetermined rotation amount obtained by adding a slight margin to the rotation amount of the feeding roller 20 necessary for eliminating the skew of the maximum skew amount. Note that the reverse butting operation is employed when the paper P is relatively thick and hard, such as special paper (photo paper, etc.), or when the printing mode requires high-speed feeding operation of the paper P. Is preferred.

  When the reverse rotation abutting operation is completed, the rotation direction of the conveyance motor 42 is switched from reverse rotation to forward rotation, and as shown in FIGS. Is rotated in the forward direction. By switching the rotation direction, the skew removing operation is switched to the cueing operation, and the paper P from which the skew is removed by this cueing operation is fed to the printing start position. In this reverse rotation abutting method, a relatively large load is applied to the feeding motor 41 during the reverse rotation abutting operation shown in FIGS.

  Next, the skew removal operation of the biting discharge method will be described with reference to FIG. The feeding operation of the biting and discharging method includes three operations including a biting operation, a discharging operation, and a cueing operation.

  As shown in FIGS. 6A and 6B, the feeding motor 41 and the conveying motor 42 are driven to rotate in the normal rotation direction that is the paper feeding direction, so that the feeding roller 20 and the conveying roller pair 43 are rotated in the normal rotation direction. By rotating, the paper P is fed along the feeding path. After the leading edge of the paper P reaches the transport roller pair 43 and is sandwiched between them, the paper P is further transported, and the leading edge of the paper P is a predetermined amount on the downstream side in the transport direction Y with respect to the transport roller pair 43. When reaching the position protruding by (amount), the driving of the feeding motor 41 and the conveying motor 42 is stopped.

  Next, as shown in FIGS. 6C and 6D, the feeding motor 41 is driven in the reverse direction while the feeding motor 41 is stopped. As a result, the transport roller pair 43 rotates in the direction opposite to the direction during transport of the paper P while the feeding roller 20 is stopped, and the leading end of the paper P is upstream of the transport roller pair 43 in the transport direction. Vomited to the side. Since this discharge operation is performed under the stopped state of the feeding roller 20, the sheet P is downstream in the transport direction from the portion pressed by the feeding roller 20, as shown in FIGS. It will bend in the side part. When the leading edge of the sheet P is discharged from the conveying roller pair 43 to the upstream side in the conveying direction, the leading edge of the sheet P hits the conveying roller pair 43 with a restoring force that causes the bent sheet P to return to the original state. Rotating and the skew with respect to the transport direction Y of the paper P is eliminated.

  When the discharge operation is finished, the transport motor 42 is switched to drive in the forward direction and the drive of the feed motor 41 in the forward direction is resumed, and the feed is performed in the same manner as in FIGS. The cueing operation is started by the forward rotation of the feed roller 20 and the forward rotation of the transport roller pair 43, and the paper P is transported to the printing start position. In this biting discharge method, a relatively large load is applied to the transport motor 42 during the discharge operation shown in FIGS.

  In the present embodiment, as an example, a reverse abutting method is employed in which both motors 41 and 42 are driven during skew removal in the AC power mode, and the transport motor 42 of both motors 41 and 42 is in the battery mode. Adopted a biting discharge system that only drives. Note that an appropriate combination of the power supply mode and the skew removal method can be set.

  Next, the electrical configuration of the printer 11 will be described with reference to FIG. As shown in FIG. 7, the controller 50 provided in the printer 11 includes a power supply device 51, a computer 52 (microcomputer), a display drive circuit 53, a head drive circuit 54, and motor drive circuits 55 to 57. The computer 52 is connected with an operation unit 15, a paper presence / absence sensor 47, a paper detection sensor 48, a paper width sensor 49, a linear encoder 39 and encoders 58 and 59 as input systems. The computer 52 is connected with a display drive circuit 53, a head drive circuit 54, and motor drive circuits 55 to 57 as an output system.

  The power supply device 51 inputs a direct current of a predetermined voltage (primary voltage) obtained by transforming or rectifying the alternating current voltage from the commercial alternating current power supply 30 through the AC adapter 27, and the direct current voltage is input to the recording head 23, the motor 35, The voltage is increased to a voltage necessary for driving 41 and 42. Then, the power supply device 51 supplies the boosted voltage to the motors 35, 41, and 42 through the motor drive circuits 55 to 57 in one system, and steps down the voltage to a plurality of types of voltages in the other system. Necessary voltages are supplied to the head 23, the display unit 14, the computer 52, the input system, and the like.

  Further, the battery 28 accommodated in the apparatus main body 12 is electrically connected to the power supply apparatus 51. The computer 52 has a function of detecting a voltage at a predetermined location on an electric circuit in the power supply device 51 and detecting connection of the AC adapter 27 and connection of the battery 28 based on the detected voltage. Therefore, the computer 52 can recognize whether the power source of the power supply at that time is the AC adapter 27 (that is, the commercial AC power source 30) or the battery 28. The computer 52 sets the power mode to “AC power mode” when the connection of the AC adapter 27 is detected, and sets the power mode when the connection of the AC adapter 27 is not detected and the connection of the battery 28 is detected. “Battery mode”. In the present embodiment, the AC power supply unit, which is a part that outputs the power input from the AC adapter 27 in the power supply device 51 at a predetermined voltage, and the battery 28 constitute an example of the power supply unit.

  When the computer 52 outputs the command values to the motor drive circuits 55 to 57, drive voltages corresponding to the command values are applied to the motors 35, 41, and 42. At this time, a motor current corresponding to the applied drive voltage flows through the motors 35, 41 and 42. The command value is output as, for example, a PWM (pulse width modulation) signal, and a current corresponding to the duty ratio of the PWM signal (ratio of the pulse width to the period of the PWM signal) flows through each of the motors 35, 41, and 42.

  Also, the paper presence sensor 47 shown in FIG. 7 is an optical or contact sensor that can detect the presence or absence of the paper P on the feeding tray 16. In addition, the paper detection sensor 48 detects the leading edge of the paper P at a predetermined position on the feeding path, and the position when the leading edge is detected measures the position (transport position) in the transport direction Y of the paper P. Used for the reference position. Further, the paper width sensor 49 is a reflective optical sensor that is provided in the carriage 21 and can detect the side edge of the paper P by moving in the scanning direction X while irradiating the detection light toward the support base 38. Based on the detection signal, it is possible to detect the width of the paper P and the leading edge in the transport direction Y.

  The linear encoder 39 outputs a pulse signal having a number of pulses proportional to the amount of rotation of the carriage motor 35. The encoder 58 outputs a pulse signal having a number of pulses proportional to the rotation amount of the feeding motor 41. Further, the encoder 59 outputs a pulse signal having a number of pulses proportional to the rotation amount of the transport motor 42. Each encoder 58, 59 is constituted by a rotary encoder connected to the end of the drive shaft of the corresponding motor 41, 42 or the rotation shaft of its power transmission system.

  As shown in FIG. 7, the computer 52 includes a CPU 61, an ASIC 62 (Application Specific IC), a RAM 63, and a nonvolatile memory 64. The CPU 61 performs various controls such as a printing system, an operating system, and a display system by executing a control program (for example, a firmware program) stored in the nonvolatile memory 64. Particularly in the present embodiment, the CPU 61 executes a feeding operation according to the mode (power mode and printing mode) by executing the feeding control program shown in the flowchart of FIG. 13 stored in the nonvolatile memory 64. Governs motor control. Further, the RAM 63 temporarily stores print data, the calculation result of the CPU 61, and the like.

  As shown in FIG. 7, the nonvolatile memory 64 is referred to when acquiring the control table TD1 that is referred to when acquiring a command value for controlling the speed of the motor and the threshold value MLo used for the motor control described above. The reference table TD2 to be stored is stored. The control table TD1 is prepared for each of the motors 35, 41, and 42, and the reference table TD2 is prepared for each of the motors 41 and 42 used for the feeding operation.

  FIG. 4 shows the speed profile of the motor. In the graph shown in FIG. 4, the horizontal axis represents the distance D that the print medium (paper P) has moved from the start of driving the motor, and the vertical axis represents the motor rotation speed U (rpm). The speed profile includes an acceleration region (acceleration profile) until the motor rotational speed U reaches 0 to zero, a constant speed region where the motor rotational speed U is held at the constant speed Uc, and a motor rotational speed U. Is a deceleration region (deceleration profile) that decelerates from a constant speed Uc to a speed 0 (zero) at which the print medium stops at the target position of the distance De.

  As shown in FIG. 4, speed profiles having different constant speeds Uc are set for each power supply mode. For example, the speed profile BV (solid line) for the battery mode is more stable than the speed profile AV (dotted line) for the AC power supply mode. The speed Uc is set to a lower speed. That is, the AC power mode is the high-speed printing mode, and the battery mode is the low-speed printing mode. This is because the supply power of the battery 28 is smaller than the supply power of the AC power supply unit. A plurality of types of speed profiles AV and BV in the respective power supply modes shown in FIG. 4 are prepared for the motors 35, 41, and 42 with different constant speeds, and are stored in the nonvolatile memory 64 as the control table TD1. The computer 52 refers to the control table TD1, acquires a command value corresponding to the rotational speed corresponding to the position, and controls the speeds of the motors 35, 41, and 42 based on the command value.

  In the plurality of operations constituting the feeding operation, at least one of the feeding motor 41 and the transport motor 42 driven for the corresponding operation is driven and controlled by the speed profile shown in FIG. In the present embodiment, one operation constituting the feeding operation is an operation of one section divided by driving from at least one stop state of the feeding motor 41 and the transport motor 42 or by stopping from the driving state. Point to. Therefore, at the start and end of one operation, driving from at least one of the feeding motor 41 and the conveyance motor 42 is stopped or stopped from the driving state.

  The reference table TD2 stored in the non-volatile memory 64 shown in FIG. 7 uses a print mode, a power mode, and a print medium type (for example, paper type) as parameters, and one threshold value MLo corresponding to each parameter combination is determined. Table. When a jam (for example, paper jam) occurs in the middle of the feeding operation, the print medium (for example, paper P) is jammed in the feeding roller 20 or the conveyance roller pair 43, and the load on the motors 41, 42 increases. Control is performed to cause an excessive current to flow through 42. In order to avoid this, the computer 52 detects the load ML (hereinafter, also referred to as “motor load ML”) of the motors 41 and 42 during the feeding operation, and the motor load ML is set to a threshold value MLo ( When the allowable load) is exceeded, the driving of the motors 41 and 42 is forcibly stopped via the motor driving circuits 56 and 57. For this reason, the motors 41 and 42 are forcibly stopped when a jam or a fatal error in which the motor load ML becomes excessively large occurs. Note that one threshold value MLo common to the print mode, the power supply mode, and the type of print medium (for example, paper type) may be used. Further, instead of the reference table TD2, a calculation formula for calculating a threshold value may be stored in the nonvolatile memory 64, and the threshold value may be calculated using this calculation formula with each parameter as a variable.

  FIG. 8 shows functional blocks constructed in the computer 52 by software and hardware such as an electronic circuit in the ASIC 62 when the CPU 61 executes a predetermined program including the feeding control program shown in FIG. As shown in FIG. 8, the computer 52 includes a main control unit 70, a motor control unit 71, a CR counter 72, an ASF counter 73, a PF counter 74, a display control unit 75, and a head control unit 76.

  The main control unit 70 is responsible for overall control of the printing system, operation system, display system, and the like of the printer 11. The main control unit 70 includes a mode management unit 70a that manages the power supply mode and the print mode. The main control unit 70 detects the power source of the power supply source in the power supply device 51. The mode management unit 70a manages the power mode as the AC power mode if power is supplied from the AC adapter 27, and manages the power mode as the battery mode if power is supplied from the battery 28. Further, the computer 52 acquires the print mode based on the print condition information in the print data PD received from the host device or the print condition information received from the operation unit 15. The mode management unit 70a also manages whether the print mode is “draft mode” (high-speed low-quality mode) or “clean mode” (low-speed high-quality mode). There may be three or more print modes.

  The motor control unit 71 controls driving of each motor 35, 41, 42 via the motor drive circuits 55 to 57 in accordance with instructions from the main control unit 70. The motor control unit 71 includes a command unit 71A that outputs a command value for controlling each of the motors 35, 41, and 42 to the motor drive circuits 55 to 57, and a determination as to whether or not the motor load ML exceeds a threshold value MLo. A determination unit 71B that performs various determinations on motor control.

  The CR counter 72 adds to the count value every time the pulse edge is detected during the forward movement of the carriage 21 based on the pulse signal from the linear encoder 39, and from the count value every time the pulse edge is detected during the backward movement. By subtracting, a count value indicating the position (carriage position) of the carriage 21 in the scanning direction X is output. The CR counter 72 counts two types of count values: a count value that is reset when the carriage 21 is at the origin position (for example, the home position) and a count value that is reset when the carriage 21 starts to move.

  The ASF counter 73 adds the count value to the count value each time a pulse edge is detected when feeding the paper P downstream in the paper feed direction based on the pulse signal from the encoder 58, so that the position of the paper P in the paper feed direction. A count value indicating (feed position) is counted. Note that the ASF counter 73 includes a count value that is reset when driving of the feeding motor 41 when starting feeding of the paper P at the feeding start position (when stopped) and a plurality of feeding operations. Two types of count values are counted, including a count value that is reset at the start of each operation.

  Further, the PF counter 74 adds to the count value every time a pulse edge is detected when the paper P is transported downstream in the transport direction Y based on the pulse signal from the encoder 59, and the PF counter 74 returns to the transport direction Y upstream of the paper P. Each time a pulse edge is detected during conveyance, a count value indicating the position (conveyance position) of the paper P in the conveyance direction Y is output by subtracting from the count value. The PF counter 74 has two types, a count value that is reset when the leading edge of the paper P is detected by the paper detection sensor 48 and a count value that is reset when the transport motor 42 starts to be driven (when stopped). Count the count value.

  The command unit 71A motor-drives the command value acquired by calculating the detected speed of the carriage 21 close to the target speed acquired by referring to the carriage control table TD1 based on the distance D indicated by the count value of the CR counter 72. By outputting to the circuit 55, the carriage motor 35 is speed controlled. Further, the command unit 71A acquires the detected feeding speed of the paper P by a calculation that brings the detected speed close to the target speed obtained by referring to the feeding control table TD1 based on the distance D indicated by the count value of the ASF counter 73. By outputting the command value to the motor drive circuit 56, the speed of the feed motor 41 is controlled. Further, the command unit 71A obtains a command value acquired by a calculation that brings the detected transport speed of the paper P closer to the target speed acquired by referring to the transport control table TD1 based on the distance D indicated by the count value of the PF counter 74. By outputting to the motor drive circuit 57, the conveyance motor 42 is speed controlled. The command unit 71A turns on / off the switching elements in the motor drive circuits 55 to 57 based on the PWM signal corresponding to the command value, so that a motor current corresponding to the command value flows in each of the motors 35, 41, and 42. . Instead of feedback control, feedforward control that outputs a command value determined from a cycle T according to the distance D may be performed.

  By the way, since the supply power of the battery 28 is smaller than the supply power of the AC adapter 27, in order to avoid a system down or the like, the threshold value MLo in the battery mode used by the determination unit 71B for the determination is set to the value in the AC power mode. It is preferable to set it smaller than the threshold value MLo. However, when the reverse rotation butting operation (FIGS. 5A and 5B) and the discharging operation (FIGS. 6C and 6D) performed during the feeding operation are performed. A relatively large load is applied to the motors 41 and 42. If the threshold value MLo is set low in accordance with the power supplied to the battery 28 in the battery mode, the motor load ML applied to the motors 41 and 42 during the skew removal operation exceeds the threshold value MLo, and the motors 41 and 42 are forcibly forced. There is a risk of being stopped. For this reason, in the present embodiment, during the period in which the skew removal operation is performed in the feeding operation, control for forcibly stopping the driving of the motors 41 and 42 is not performed even if the motor load ML exceeds the threshold value.

  In the present embodiment, the current value of the current flowing through the motors 41 and 42 is used as the motor load ML. As the current value at this time, a current value determined from a command value when driving the motors 41 and 42 is used. Of course, the motor load ML is not limited to a current value, and may be a physical quantity having a value corresponding to the motor load ML. For example, a motor torque, a voltage value, a power value, or the like may be used. In this case, the motor load ML may be calculated using a command value, may be detected by a sensor, or may be calculated using a detection value of the sensor.

  In this embodiment, the threshold value MLo is set to a value that can be detected from the motor load ML that the skew removal has been completed. Here, the motor load ML increases as the paper feeding speed increases. For this reason, the threshold value MLo in the low-speed printing mode is set lower than the threshold value MLo in the high-speed printing mode. Further, the load ML of the motors 41 and 42 during the skew removing operation depends on the paper type and the paper size. The thicker the paper, the larger the load ML of the motors 41 and 42 tends to be. In addition, the load ML of the motors 41 and 42 is larger for glossy paper than for plain paper. Further, the load ML of the motors 41 and 42 is larger when the paper size is larger. For this reason, the threshold value MLo is set to a larger value as the paper type is thicker, the glossy paper is larger than the plain paper, and the paper size is larger.

  Further, the display control unit 75 shown in FIG. 8 controls display of the display unit 14 via the display drive circuit 53 in accordance with an instruction from the main control unit 70, and displays a warning message that a paper jam has occurred on the display unit 14. indicate. Further, the head control unit 76 controls the recording head 23 by transmitting print image data in the print data PD to the head drive circuit 54 according to an instruction from the main control unit 70. During the scanning of 21, ink droplets based on the print image data are ejected from the recording head 23.

  The host device (not shown) for transferring the print data PD to the printer 11 includes a mobile terminal such as a smartphone, a mobile phone, a tablet PC, a personal digital assistant (PDA (Personal Digital Assistants)), or a personal computer. Is mentioned.

  Next, the motor load during the skew removal operation will be described with reference to FIGS. 9 and 10 are examples of the reverse contact method, and FIGS. 11 and 12 are examples of the biting discharge method. As shown in FIG. 9A, in the case of the reverse contact method, the motor load ML is small before the paper P hits the transport roller pair 43. As shown in FIG. 9B, when the corner portion at the downstream end in the transport direction Y of the paper P abuts on the reverse transport roller pair 43, the paper P rotates in a direction in which the skew amount decreases, Skew removal is performed by the rotation of the paper P. As shown in FIG. 9C, when the skew amount becomes almost zero and the skew is removed, the sheet P hits the reverse conveying roller pair 43 on the entire downstream end in the conveying direction Y. In this state, since the leading edge of the paper P hits the transport roller pair 43 and the movement of the paper P in the transport direction Y is restricted, a large load is applied to the feeding roller 20.

  As shown in FIG. 10A, the load ML of the feeding motor is low during the period “before abutment” of the paper P, and the front end of the paper P abuts against the transport roller pair 43 and the paper P rotates. It rises slowly during the "skew" period. As shown in FIG. 10B, the skew amount θ gradually decreases with the rotation of the paper P during the skew removal period. Then, when the skew is removed and the leading edge of the paper P contacts the conveying roller pair 43 over the entire side, the load ML of the feeding motor is relatively steep and the maximum load MLmax as shown in FIG. Until the maximum load MLmax is maintained. Here, since the skew amount θ of the paper P is not known, the maximum skew amount θmax is assumed and the motors 41 and 42 are driven by the rotation amount necessary to remove the skew of the maximum skew amount θmax. Thus, the execution period of the skew removal operation is set.

  Here, when the skew removal operation is continued until the skew is removed, the motor load ML increases, a large current flows through the motor 41, and the power consumption of the motors 41 and 42 increases. For example, in the battery mode, the total power consumption of the printer 11 may exceed the supply power of the battery 28 due to an increase in power consumption of the motors 41 and 42, leading to a system down. Further, if the skew removal operation is continued until the skew is removed, useless waiting time increases, which causes a decrease in throughput of the feeding operation. For this reason, after the skew is removed, the operation shifts to the next operation without waiting for the completion of the skew removal operation before the motor load ML reaches the maximum load MLmax.

  In the case of the reverse abutting method, the threshold value MLo is set while the load ML is increasing after the skew is removed. When it is detected that the skew has been removed because the motor load ML exceeds the threshold value MLo, the process proceeds to the next operation without waiting for the completion of the skew removal operation. In this case, the threshold value MLo may be the same value as the threshold value for jam detection for detecting a jam (for example, paper jam) of the print medium in the battery mode, but in this example, the power mode, the print mode, The threshold value MLo is changed according to the medium information regarding the type and size of the print medium. That is, the threshold value MLo is set according to the maximum load MLmax assumed at the time of skew removal, which changes according to the power supply mode, the printing mode, and the medium information so that when the completion of the skew removal operation is detected, the next operation can be immediately performed. It is changing.

  Here, the motor load ML changes according to the power mode, the print mode, the paper type of the paper P, and the paper size. When the printing mode is the same, the feeding speed when the power mode is the battery mode is lower than the feeding speed when the AC mode is the power mode. When the power modes are the same, the feeding speed when the printing mode is the low-speed printing mode (clean mode) is lower than the feeding speed when the printing mode is the high-speed printing mode (draft mode). Since the motor load ML increases as the feeding speed of the paper P increases, when the power mode is the same, the threshold value MLo is set smaller in the low-speed printing mode than in the high-speed printing mode. The When the print modes are the same, the threshold value MLo is set smaller in the battery mode than in the AC power mode.

  Further, the motor load ML changes according to the paper type of the paper P. For example, the thicker the paper P, the larger the motor load ML during the skew removing operation. Further, a paper type having a gloss layer (coating layer) on the surface thereof such as glossy paper has a larger coefficient of friction with the feeding roller 20 and the conveying roller pair 43 than plain paper, and the motor load ML during the skew removing operation is larger. Tend to be. Furthermore, the motor load ML tends to increase as the paper size of the paper P increases. Therefore, the threshold value MLo is set to a larger value as the paper thickness determined from the paper type is thicker, the paper type having the glossy layer is larger, and the paper size is larger.

  In the present embodiment, in the AC power mode, the load ML of the feed motor 41 (an example of the first motor) is used among the feed motors 41 and 42, and the motor load ML exceeds the threshold value MLo. It is determined whether or not. On the other hand, in the battery mode, the load ML is defined as the sum of the load of the feeding motor 41 (an example of the first motor) and the load of the transport motor 42 (an example of the second motor), and whether the motor load ML exceeds the threshold value MLo. Determine whether or not.

  Further, as shown in FIG. 11A, in the case of the biting discharge method, the period of the biting operation in which the paper P is conveyed from the conveyance roller pair 43 to a position protruding by a predetermined length downstream in the conveyance direction Y. Then, the motor load ML is small. As shown in FIG. 11B, in the skew removal period that is performed when the transport roller pair 43 is reversed and the paper P is discharged to the upstream side in the transport direction Y, the paper P is in a stopped state. In the process of bending between the pair of transport rollers 43 in reverse rotation, the load that the pair of transport rollers 43 receives from the paper P increases as the deflection of the paper P increases. When the leading end on the downstream side in the transport direction Y of the paper P is discharged from the transport roller pair 43, the skew is removed when the bent paper P returns to the original flat state at once. At this time, the load that the conveying roller pair 43 receives from the paper P decreases at a stretch, and the skew removal is completed as shown in FIG.

  As shown in FIG. 12A, the load ML of the transport motor 42 is low during the biting operation period, and increases during the “skew removal” period during which the paper P is discharged. It descends at once when spitting is completed. As shown in FIG. 12B, the skew amount θ decreases at a stretch by this discharge. After the skew is removed, the load ML is held at a lower level. Here, since the skew amount θ of the paper P is not known, the transport motor 42 is driven in reverse by the amount of rotation necessary to remove the skew of the maximum skew amount θmax. As described above, even in the case of the biting discharge method, the execution period of the skew removal operation is set.

  Here, when the skew removal operation is continued until the skew is removed, the throughput of the feeding operation is lowered due to the waiting time, and the power of the transport motor 42 that is driven to rotate unnecessarily is wasted. Is done. For this reason, after the skew is removed, the next operation is promptly shifted without waiting for the completion of the skew removal operation.

  In the present embodiment, in the case of the biting discharge method, it is detected that the skew has been removed when the motor load ML that has risen in the process of bending the paper P has dropped due to the completion of the discharge of the paper P. When it is detected that the skew has been removed, the process proceeds to the next operation without waiting for the completion of the skew removal operation. In the case of the biting discharge method, since only the transport motor 42 is driven among the feed motors 41 and 42, the motor load ML due to the skew removing operation is increased so as to cause a system down even in the battery mode. Absent. However, in consideration of the case where a jam occurs during the skew removal period, even when the motor load ML exceeds the threshold value MLo, the operation is shifted to the next operation without waiting for the completion of the skew removal operation. The threshold value MLo at this time is a threshold value for jam detection.

  Here, the motor load ML changes according to the power mode, the print mode, the paper type of the paper P, and the paper size. The motor load ML increases as the feeding speed of the paper P increases. In this example, even if the print mode is the same, the feeding speed is set lower in the battery mode than in the AC power mode. Therefore, when the print mode is the same, the motor load ML has the power mode AC. The power mode is larger than the battery mode. When the power modes are the same, the motor load ML is larger when the print mode is the high-speed print mode (draft mode) than when the print mode is the low-speed print mode (clean mode).

  Further, the thicker the paper P, the larger the motor load ML during the skew removal operation. Further, a paper type having a gloss layer (coating layer) on the surface thereof such as glossy paper has a larger coefficient of friction with the feeding roller 20 and the conveying roller pair 43 than plain paper, and the motor load ML during the skew removing operation is larger. Become. Furthermore, the motor load ML tends to increase as the paper size of the paper P increases.

  In the next operation after the skew removal operation is completed during the feeding operation, the motor load ML is monitored in order to detect occurrence of a jam (for example, paper jam) of the print medium, and when the motor load ML exceeds the threshold value MLo. If an abnormality such as a jam occurs, the motors 41 and 42 are forcibly stopped. By the way, if it is detected that a jam is abnormal in spite of the normal skew removing operation, the skew removing operation is forcibly stopped. In order to avoid this, the skew removal operation period is a prohibition period in which abnormality detection processing such as a jam is prohibited. A jam occurring during the skew removal operation period is detected after a transition from the skew removal operation to the next operation. Note that the jam abnormality detection threshold value may be set to a value different from the skew removal operation completion detection threshold value MLo.

Next, the operation of the printer 11 will be described.
The motor control during the feeding operation will be described with reference to the flowchart shown in FIG. The computer 52 that has received the print data PD drives the feed motor 41 and the transport motor 42 to perform a feeding operation for feeding the paper P from the hopper 18 of the automatic feeding device 17 to the printing start position. . In this feeding operation, the paper P is fed at a feeding speed corresponding to the current mode (power supply mode and printing mode), and skew correction corresponding to the current mode is performed during the feeding process. A skew removing operation is performed to remove skew (skew) of the paper P by this method. For example, the mode in which the reverse abutting method is selected is the first mode, and if it is the first mode, the skew removing operation by the reverse abutting method shown in FIG. 5 that drives both the feeding motor 41 and the conveying motor 42 is performed. Is done. On the other hand, the mode in which the biting discharge method is selected is the second mode. If the mode is the second mode, the biting discharge shown in FIG. 6 is performed in which the transport motor 42 is driven with the feeding motor 41 stopped. A skew removing operation is performed by the method. During the feeding operation, the computer 52 detects the load ML of the motors 41 and 42 at a predetermined time interval within a range of 10 μs to 200 milliseconds, for example. In addition, the PF counter 74 counts a count value indicating the transport position of the paper P based on the position where the leading edge of the paper P is detected by the paper detection sensor 48. The computer 52 grasps the transport position of the paper P from the count value of the PF counter 74. Therefore, the computer 52 can determine whether or not the sheet is in a skew removal section where skew removal is performed. During the feeding operation of the paper P, a count value indicating the rotation amount of the feeding roller 20 is counted by the ASF counter 73 for each operation, and a count value indicating the rotation amount of the transport roller pair 43 is calculated by the PF counter 74. Counted.

When the computer 52 receives an instruction to start printing by receiving the print data PD or operating the operation unit 15, the computer 52 starts the following processing.
First, in step S11, medium information regarding the power mode, print mode, and print medium is acquired. The computer 52 acquires whether the power mode is the AC power mode or the battery mode from the mode management unit 70a. The computer 52 acquires whether the print mode is the high-speed print mode (draft mode) or the low-speed print mode (clean mode). As the medium information, at least one of a paper type such as plain paper and photographic paper (glossy paper) and a paper size is acquired.

  In step S12, a feeding speed and a skew removal method corresponding to the power mode and the printing mode are determined. For example, for the power mode, a lower feeding speed is selected in the battery mode than in the AC power mode. As for the printing mode, a lower feeding speed is selected in the “clean mode” than in the “draft mode”. In addition, as an example of the skew removal method, the “reverse rotation butting method” is selected in the AC power supply mode, and the “eating and discharging method” is selected in the battery mode. These selection processes are performed by the main control unit 70.

  In step S13, a threshold value MLo corresponding to each mode, a skew removal method, and medium information is determined. The threshold value MLo is set to a larger value as the feeding speed of the paper P is higher, that is, the driving speed of the motors 41 and 42 is higher, and the threshold MLo is set to a smaller value as the power supply power is lower. Specifically, the threshold value MLo is set to a larger value in the high-speed printing mode than in the low-speed printing mode, and is set to a smaller value in the battery mode than in the AC power supply mode. In the case of the reverse contact method, a threshold value MLo corresponding to the load ML indicating that the skew removal operation has been completed is set. Further, the medium information includes a medium type (for example, a paper type) and a medium size (for example, a paper size). For example, the paper type is a paper type having a coating layer such as glossy paper, and the paper thickness. As the paper type is thicker, the threshold value MLo is set to a larger value. As for the medium size, the threshold value MLo is set to a larger value as the paper size is larger. In the case of the biting discharge method, the completion of the discharge operation, which is a skew removal operation, is detected from the rise and fall behavior of the load ML, and the determination using the threshold value MLo is not performed. A threshold value MLo is set.

  In step S14, the feeding operation is performed using the determined skew removal method. For example, in the case of the reverse abutting method, the motor control unit 71 controls the motors 41 and 42 and performs the operations shown in FIGS. 5 (a) and 5 (b). The motors 41 and 42 are controlled to perform the operations shown in FIGS.

In step S15, the skew removal method is determined. If the reverse abutting method is used, the process proceeds to step S16.
For example, in the case of the reverse abutting method, as shown in FIG. 9A, the motor load ML is small at the stage before the paper P is abutted against the conveyance roller pair 43 (see FIG. 10A). As shown in FIG. 9B, in the process from when the paper P hits the conveying roller 43 in reverse rotation until the skew is removed with the rotation of the paper P, the motor load ML is as shown in FIG. Gradually grows. When the skew is removed as shown in FIG. 9C, the motor load ML increases more rapidly than before until the maximum load MLmax as shown in FIG. 10A. At this time, if the set threshold value MLo is smaller than the maximum load MLmax, the threshold value MLo is exceeded in the process of increasing the motor load ML after the completion of skew removal.

  On the other hand, in the case of the biting discharge method, for example, as shown in FIG. 11A, the motor load ML is small at the stage where the leading end of the paper P bites against the conveying roller pair 43 (see FIG. 12A). Then, as shown in FIG. 11 (b), under the stopped state of the feeding roller 20, a skew removal process (discharge process) for discharging the biting portion of the paper P from the transport roller pair 43 by the reverse rotation of the transport roller pair 43. ), The motor load ML gradually increases as shown in FIG. Then, at the moment when the leading end of the sheet P is discharged from the transport roller pair 43, the motor load ML is lowered at a stroke. That is, as shown in FIG. 11B, the motor load ML increases in the process where the upstream portion of the transport roller pair 43 in the paper P is bent as shown in FIG. Since the conveying roller pair 43 does not receive the restoring force due to the bending of the maximum load MLmax, the motor load ML drops at a stroke from the moment of discharge. Then, after the skew is removed as shown in FIG. 11 (c), even if the reverse rotation of the transport roller pair 43 is continued, the motor load ML is small after being lowered as shown in FIG. 12 (a). Held in value. If the rising and falling behavior of the motor load ML is detected during the skew removal (discharge) process, it is determined that the skew removal has been completed.

  In step S16, it is determined whether or not the motor load ML exceeds the threshold value MLo (whether ML> MLo is satisfied) during the skew removal operation. That is, when the feeding position of the paper P enters the skew removal operation section, the computer 52 determines whether or not the motor load ML exceeds the threshold value MLo. In this example, for example, a motor current value determined from a command value is used as the motor load ML, and it is determined whether or not the current value exceeds a threshold value. At this time, if the power supply mode is the AC power supply mode, it is determined whether ML> MLo is satisfied using the load ML of the transport motor 42. On the other hand, in the battery mode, the sum of the load of the feeding motor 41 and the load of the transport motor 42 is set as the motor load ML, and it is determined whether ML> MLo is satisfied. As the threshold value MLo at this time, a threshold value corresponding to the sum of the load of the feeding motor 41 and the load of the transport motor 42 is used. If the motor load ML does not exceed the threshold value MLo (ML ≦ MLo), the process proceeds to step S17. If the motor load ML exceeds the threshold value MLo (ML> MLo), the process proceeds to step S20.

  In step S17, it is determined whether or not the skew removal step number Sk exceeds a set value So (whether Sk> So is satisfied). If Sk> So is not established, the process returns to step S16, and if Sk> So is established, the process proceeds to step S20. Note that the set value So in the reverse abutting method is set to a value that can eliminate the maximum skew amount θmax.

  For example, when the process returns from step S17 to step S16, it is determined in step S16 whether or not the motor load ML exceeds the threshold value MLo until the skew removal step number Sk exceeds the set value So necessary for the skew removal operation. Therefore, when the motor load ML during the skew removal operation exceeds the threshold value MLo and ML> MLo is established in step S16, or when the skew removal step number Sk exceeds the set value So, the skew removal operation is finished. Proceed to step S20.

  On the other hand, in step S18, it is determined whether or not the increased motor load ML has decreased during the skew removal operation. That is, the computer 52 determines whether or not the motor load ML, which has been raised by the skew removal operation (discharge operation), has been lowered due to the completion of discharge in the skew removal operation section of the paper P. In this example, the motor load ML is determined based on the motor current value. For example, when a behavior in which the increased current value decreases is determined, it is determined that the discharge operation has been completed. If the motor load ML does not decrease after the increase, the process proceeds to step S19. If the motor load ML decreases after the increase, the process proceeds to step S20. However, even when the motor load ML does not detect a decrease after the increase, if the motor load ML exceeds the jam detection threshold MLo, the process proceeds to step S20.

  In step S19, it is determined whether or not the skew removal step number Sk exceeds a set value So (whether Sk> So is satisfied). If Sk> So is not established, the process returns to step S18, and if Sk> So is established, the process proceeds to step S20. For this reason, a behavior in which the motor load ML during the skew removal operation decreases after being detected is detected, whether the motor load ML exceeds the threshold value MLo (Yes in S18), or the skew removal step number Sk is equal to the set value So. If the skew removal operation has been completed to the end (Yes in S19), the process proceeds to step S20. Note that the set value So in the biting discharge method is a value corresponding to the discharge amount at which the sheet P skewed with the maximum skew amount θmax can be discharged to the upstream side of the conveying roller pair 43, or a slight margin. It is set to the value with the amount added.

  In step S20, a cueing operation is performed. That is, the computer 52 drives both the feed motor 41 and the transport motor 42 in the forward rotation direction, and rotates each of the feed roller 20 and the transport roller pair 43 in the forward rotation direction, thereby causing the paper P to be printed at the print start position. Transport to.

  In step S21, it is determined whether the motor load ML has exceeded the threshold value MLo (whether ML> MLo is satisfied) during the cueing operation. If the motor load ML does not exceed the threshold value MLo (ML ≦ MLo), the process proceeds to step S22. If the motor load ML exceeds the threshold value MLo (ML> MLo), the process proceeds to step S23.

In step S22, the sequence is continued. That is, the computer 52 continues the cueing operation.
In step S23, the display unit 14 displays a message indicating a paper jam to warn the user, and at the same time, stops driving the motors 41 and 42. At this time, if the cueing operation of the paper P approaches the end and the driving of the carriage motor 35 is started, the motors 35, 41, 42 are forcibly stopped.

According to the embodiment described in detail above, the following effects can be obtained.
(1) Control the motors 41 and 42 to cause the feeding mechanism (the feeding roller 20 and the conveying roller pair 43) to perform a skew removal operation for removing the skew of the paper P in the middle of the paper P feeding operation. If the load of the motor 41 satisfies the condition indicating that the skew of the paper P has been removed during the operation, the skew removal operation is terminated and the operation proceeds to the next operation. Therefore, since it is possible to shift to the next operation (cue operation) without waiting for the end of the skew removal operation, the time required for the paper P feeding operation can be shortened. Further, since the situation where the motor load reaches the maximum load MLmax after completion of the skew removal can be avoided as much as possible, the power consumption of the motors 41 and 42 can be made relatively small. Further, it is possible to reduce the frequency at which the motor load ML after the skew removal ends up to the maximum load MLmax. For example, even if the jam detection threshold value MLo is set to be small in the battery mode, even if the motor load ML exceeds the threshold value MLo by the skew removal operation, the operation can be shifted to the next operation without being abnormally stopped.

  (2) In the reverse rotation butting method, as a condition, when the load ML of the feeding motor 41 exceeds the threshold value MLo during the skew removing operation, the operation proceeds to the next operation (cueing operation). Therefore, in the reverse rotation abutting operation for abutting the paper P against the reverse conveying roller pair 43, it is possible to shift to the next operation as soon as the skew is removed without waiting for completion of the reverse rotation abutting operation (skew removing operation). .

  (3) In the biting discharge method, as a condition, when a behavior in which the load ML of the motor 42 is lowered after rising is detected during the skew removing operation, the operation proceeds to the next operation (cueing operation). Therefore, when the skew removal operation is a discharge operation in which the paper P that has bitten by the conveyance roller pair 43 is discharged to the upstream in the conveyance direction Y by reversing the conveyance roller pair 43, the discharge operation The completion of the discharge operation is detected when the motor load ML that has risen due to the restoring force that has deflected the paper P in the above process has dropped due to the completion of the discharge of the paper P. Therefore, it is possible to shift to the next operation as soon as the skew due to the discharge operation is removed without waiting for the end of the skew removal operation.

  (4) During the skew removal operation, when the skew removal step number Sk, which is the drive amount of the motor 41 or 42, exceeds the set value So (set amount), the skew removal operation is terminated and the operation proceeds to the next operation. Therefore, even when the load of the motors 41 and 42 does not exceed the threshold value MLo during the skew removing operation, the skew can be removed by performing the skew removing operation to the end, and the skew removing operation is completed and the next operation is performed. It is possible to shift to (cue operation). For example, it is possible to avoid the inconvenience that it is not possible to shift to the next operation because the load ML of the motor 41 or 42 does not exceed the threshold value MLo during the skew removing operation.

  (5) If the load ML of the motor 41 or 42 exceeds the threshold value MLo in the next operation (cue operation) after the skew removal operation, the drive of the motor is stopped as an abnormality. In the next operation, since the increase in the motor load is not caused by the skew removal operation, it can be determined that an abnormality such as a jam is the cause, and the motors 41, 42, etc. can be forcibly stopped. . Even if the skew removal operation period is a prohibition period during which jam detection is prohibited, if a jam occurs within the prohibition period, the jamming is detected after the transition to the next operation and the motors 41 and 42 are forced. The drive can be stopped automatically. For example, even if the motor load ML exceeds the threshold value MLo due to a jam during the reverse rotation abutting operation period, the jam is immediately detected and the motors 41 and 42 are detected as abnormal when the operation shifts to the next operation with the establishment of ML> MLo. Can be forcibly stopped.

  (6) The discharge operation, which is a skew removal operation of the biting discharge method performed in the battery mode, is an operation of reversing the conveying roller pair 43 under the stopped state of the feeding roller 20. Therefore, the skew of the paper P can be removed while suppressing the power consumption of the motors 41 and 42 as compared with the reverse abutting method in which both the feeding roller 20 and the conveying roller pair 43 are rotated.

  (7) In the battery mode in which the motor is driven by the power supplied from the battery 28, the drive speeds of the motors 41 and 42 are compared with those in the AC power mode in which the motor is driven by the power supplied from the commercial AC power supply 30 via the AC adapter 27. Is set lower and the threshold value MLo is set smaller. Therefore, the situation where the power consumption of the motors 41 and 42 exceeds the power supplied by the battery 28 can be reduced, and even in the battery mode, the skew removal operation is performed when the paper P is fed without causing a system down due to power shortage as much as possible. Can do.

  (8) In the case of the reverse abutting system in which both the feeding motor 41 (an example of the first motor) and the transport motor 42 (an example of the second motor) are driven to perform the skew removal operation, the AC power supply mode (first In the example of the mode), the load of the feeding motor 41 is set as the motor load ML, and it is determined whether or not the motor load ML exceeds the threshold value MLo. On the other hand, in the battery mode (an example of the second mode), the sum of the load of the feeding motor 41 and the load of the transport motor 42 is set as the motor load ML, and it is determined whether or not the motor load ML exceeds the threshold value MLo. To do. Therefore, in the AC power supply mode in which the power supply of the AC power supply unit is relatively large and the possibility that the motor power consumption exceeds the supply power of the power supply unit is relatively low even if both the motors 41 and 42 are driven simultaneously, the feeding motor Simple control that only sees the load ML 41 is sufficient. Further, if the power supplied to the battery 28 is relatively small and the motors 41 and 42 are driven at the same time, in the battery mode where the motor power consumption is likely to exceed the power supplied by the power supply unit, the feeding motor 41 Since the sum of the load and the load of the conveyance motor 42 is used, it is easy to avoid a system down that occurs when the motor power consumption exceeds the supply power.

  (9) In the AC power supply mode, a reverse abutting type skew removal operation (an example of a first skew removal operation) that drives both the feeding motor 41 and the conveyance motor 42 is performed. On the other hand, in the battery mode, a skewed discharge-type skew removal operation (an example of a second skew removal operation) is performed in which the transport motor 42 is driven while the feeding motor 41 is stopped. Therefore, it is easy to avoid a system down that occurs when the motor power consumption exceeds the power supplied by the power supply unit in both the AC power supply mode and the battery mode.

  (10) Since the threshold value MLo changes according to at least one of the print mode, the power supply mode, and the medium information related to the print medium, it is possible to shift to the next operation at an appropriate timing after the skew is removed. For example, the feeding speed of the printing medium differs depending on the printing mode, and the higher the feeding speed, the greater the load on the motor at the time of skew removal. Therefore, the threshold value MLo is set accordingly. In this case, even if the feeding speed of the printing medium differs depending on the printing mode, it is possible to shift to the next operation at an appropriate timing after the skew is removed. Further, for example, a smaller threshold value is set in the battery mode with a small supply power depending on the power supply mode than in the AC power supply mode with a relatively large supply power. In this case, it is possible to shift to the next operation at an appropriate timing from which the skew is removed while avoiding a system down according to the power supply unit. Further, for example, at the time of feeding due to the fact that the friction coefficient of the printing medium with respect to the feeding mechanism is different depending on the medium information about the printing medium (at least one of medium type (for example, paper type) and medium size (for example, paper size)). The frictional resistance force that the feeding roller 20 or the conveyance roller pair 43 receives from the paper P is different, whereby the load ML of the motors 41 and 42 is different. For this reason, the threshold value MLo is set higher as the friction coefficient of the paper P against the roller is higher. In this case, even if the load of the motor 41 or 42 is different due to the frictional resistance that the feeding roller 20 or the conveyance roller pair 43 receives from the paper P at the time of feeding depends on the type (paper type) of the paper P, the skew is different. It is possible to shift to the next operation at an appropriate timing when is removed.

In addition, the said embodiment can also be changed into the following forms.
-In the eating discharge system in the said embodiment, it is good also as a structure which detects only the behavior which motor load ML descend | falls after raising, and shifts to the next operation | movement, and motor load ML is a threshold value similarly to a reverse collision method. A configuration may be adopted in which only the determination of whether or not MLo has been exceeded is performed, and if ML> MLo is established, the operation proceeds to the next operation. As described above, when only the comparison between the motor load ML and the threshold value MLo is used as a condition, in the case of the biting discharge method, when ML> MLo is established in the stage before the discharge is completed in the middle of the discharge operation, the skew is removed. Although there is a risk of shifting to the next operation without being performed, it is more preferable to employ the reverse rotation butting method because there is no such inconvenience. Alternatively, the transfer motor 42 may reverse the rotation amount that can discharge the skew-free paper, and the operation may be shifted to the next operation when ML> MLo is established.

  Instead of detecting abnormalities such as jams by comparing the motor load ML and the threshold value MLo in the next operation after the skew removal operation, the paper is detected by the paper width sensor 49 within the predetermined number of steps from the start of the cueing operation. It may be configured to detect a jam when it is not performed.

  -The biting discharge method may be adopted in the AC power mode, and the reverse butting method may be adopted in the battery mode. In the latter case, if the feeding speed is set lower and the threshold value MLo is set smaller than in the AC power mode, it is easy to avoid a system down or the like. As the skew removal method, the reverse abutment method and the biting discharge method are employed, but only one of these skew removal methods may be employed. For example, only a reverse butting method may be employed in a printer that is not provided with a battery and that is only in the AC power supply mode. Further, for example, only the bite discharge method may be employed in a printer including a battery. For example, in a printer having both an AC power supply mode and a battery mode, the reverse abutting method may be adopted in both modes, or the biting discharge method may be adopted in both modes.

  -Other skew removal methods other than the reverse abutting method and the biting discharge method may be adopted. For example, an abutting method may be employed in which the sheet fed by rotating the feeding roller 20 in the forward state with the conveyance roller pair 43 stopped is abutted against the conveyance roller pair 43 in the stopped state. In this case, when the load ML of the feeding motor 41 exceeds the threshold value MLo, the operation may be shifted to the next operation. In addition, there may be a condition (print mode condition, power supply mode condition, medium information condition (paper type, paper size, etc.)) for not performing the skew removal operation.

A printing apparatus that does not include a battery as a power supply unit may be used.
Although the threshold value is changed according to the power supply mode, the threshold value may be the same between different power supply modes. Further, although the threshold value is changed according to the print mode, the threshold value may be the same between different print modes. Furthermore, although the threshold value is changed according to the type of print medium, the threshold value may be the same between different types of print media. Further, although the threshold value is changed according to the size of the print medium, the threshold value may be the same between different sizes of the print medium. Further, the threshold value may be changed according to at least one of the power mode, the printing mode, and the medium information, instead of changing the threshold value according to all of the power mode, the printing mode, and the medium information.

  Control that shifts to the next operation when the motor load satisfies the condition indicating that the skew has been removed may be executed only in the battery mode, not in the AC power mode. Even with this configuration, as soon as the skew removal operation in the battery mode is completed, it is possible to quickly shift to the next operation and to reduce the system down of the printer 11 due to the skew removal operation.

  In the embodiment, a battery having a large capacity (supply power) may be adopted, and the maximum rotation speed (for example, constant speed) of the motor may be the same between the supply power in the AC power supply mode and the battery mode.

The printing medium supply source may be a feeding cassette that can be inserted into and removed from the apparatus main body 12 instead of or in addition to the feeding tray 16.
-Each functional unit constituting the control unit is realized by software by a CPU that executes a program, by hardware by an electronic circuit such as an ASIC, or by cooperation of software and hardware. Also good.

  The printing apparatus may be an ink jet printer, a dot impact printer, or a laser printer as long as it can print on a printing medium such as paper P. The printing apparatus is not limited to a printer having only a printing function, and may be a multifunction machine. Furthermore, the printing apparatus is not limited to a serial printer, and may be a line printer or a page printer.

  The printing medium is not limited to paper, and may be a resin film, a metal foil, a metal film, a resin-metal composite film (laminate film), a woven fabric, a nonwoven fabric, a ceramic sheet, or the like.

  DESCRIPTION OF SYMBOLS 11 ... Printer as an example of a printing apparatus, 12 ... Apparatus main body, 14 ... Display part, 15 ... Operation part, 20 ... Feed roller which comprises an example of a feeding mechanism, 21 ... Carriage, 23 ... Recording head, 27 ... AC adapter, 28 ... battery as an example of the power supply unit and the second power supply unit, 30 ... commercial AC power supply as an example of the commercial power supply, 41 ... feed motor as an example of the motor and the first motor, 42 ... motor and second Transport motor as an example of two motors, 43 ... Pair of transport rollers constituting an example of a feeding mechanism, 51 ... Power supply device, 52 ... Computer as an example of a controller, 58, 59 ... Encoder, 70 ... Main controller, 70a: Mode management unit, 71: Motor control unit constituting an example of control unit, 71A: Command unit, 71B: Determination unit, 73: ASF counter, 7 ... PF counter, P ... paper as an example of printing medium, ML ... load (motor load), MLo ... threshold, Sk ... the number of skew removal steps as an example of motor drive amount, So ... setting as an example of set amount Value, Wac ... Supply power of AC power supply, Wb ... Supply power of battery.

Claims (9)

A feeding roller for feeding the print medium;
A pair of transport rollers provided on the downstream side in the transport direction of the print medium from the feed roller;
A first motor serving as a power source for the feeding roller;
A second motor as a power source for the pair of transport rollers;
A controller that controls the first motor and the second motor,
The controller performs a skew removing operation for removing skew of the print medium by driving one or both of the first motor and the second motor;
In the skew removal operation, the load of the motor driven among the first motor and the second motor satisfies a condition indicating that the skew of the print medium has been removed, or the driving amount of the motor is Exit deskew operation When exceeding the set amount shifts to the next operation, printing device you wherein a. A feeding roller for feeding the print medium;
A pair of transport rollers provided on the downstream side in the transport direction of the print medium from the feed roller;
A first motor serving as a power source for the feeding roller;
A second motor as a power source for the pair of transport rollers;
A controller that controls the first motor and the second motor,
The controller is configured to perform skew removal after a biting operation in which both the feeding roller and the transport roller pair are rotated forward to transport the print medium to a position protruding downstream from the transport roller pair in the transport direction. As an operation, under the stopped state of the feeding roller, reverse the transport roller pair to perform a discharge operation to discharge the print medium upstream in the transport direction,
When the load of the second motor during the previous SL skew operation detects that descends after rising, the process proceeds to the next operation to end the skew operation, printing device you wherein a. Battery,
A feeding mechanism for feeding print media;
A motor as a power source for driving the feeding mechanism;
A control unit for driving and controlling the motor,
The feed mechanism includes a feed roller for feeding a print medium and a conveying roller pair provided on the downstream side in the transport direction of the print medium than the feed roller,
When driving the motor by the power of the battery, it conveys the print medium by forward both to the conveying roller pair and the feed roller to position projecting to the downstream side in the transport direction from the transport roller pair after bite operation of, as skew removal operation of removing skew of the print medium, under the stopped state of the feeding roller, discharges the printing medium by reversing the transport roller pair to the upstream side in the transport direction When the discharge operation is performed and the load of the motor satisfies the condition indicating that the skew of the print medium has been removed during the skew removal operation, the skew removal operation is terminated and the operation proceeds to the next operation. printing device you wherein a. A first power supply unit for supplying electric power from the commercial power source,
A second power supply comprising a battery;
A feeding mechanism for feeding print media;
A motor as a power source for driving the feeding mechanism;
A control unit for driving and controlling the motor,
The control unit performs a skew removal operation for driving and controlling the motor to remove the skew of the print medium.When the load of the motor exceeds a threshold during the skew removal operation, the control unit proceeds to the next operation, When driving the motor with the power of the second power supply unit , the motor driving speed is made lower and the threshold value is made smaller than when the motor is driven with the power of the first power supply unit. printing equipment shall be the feature. A first power supply unit for supplying electric power from the commercial power source,
A second power supply comprising a battery ;
And the feed roller for feeding the print media,
A pair of transport rollers provided on the downstream side in the transport direction of the print medium from the feed roller ;
And the first motor as a power source for the previous Symbol feed roller,
A second motor as a power source for the pair of transport rollers ;
A controller that controls the first motor and the second motor,
The control unit drives both the first motor and the second motor to perform a skew removal operation,
The case of the first mode for driving the first and second motors in power supply of the first power supply unit, after exceeding a threshold load before Symbol first motor during the skew correction operation, next operation migrated, the case of the second mode for driving the first and second motors in power supply of the second power supply unit, sum threshold the previous SL first motor load and the load of the second motor Once beyond the proceeds to the next operation, printing device you wherein a. The printing apparatus according to claim 4 , wherein the threshold value changes in accordance with at least one of print mode, power supply mode, and medium information related to the print medium. A first power supply unit for supplying electric power from the commercial power source,
A second power supply comprising a battery ;
A feeding roller for feeding the print medium ;
A pair of transport rollers provided on the downstream side in the transport direction of the print medium from the feed roller ;
And the first motor as a power source for the previous Symbol feed roller,
A second motor as a power source for the pair of transport rollers ;
A controller that controls the first motor and the second motor,
When the control unit is in the first mode in which the first and second motors are driven by the power supplied from the first power supply unit, the control unit drives both the first motor and the second motor. In the second mode in which the skew removal operation is performed and the first and second motors are driven by the power supplied from the second power supply unit, one of the first motor and the second motor is stopped. There rows second skew operation for driving the other motor in the state of being, the load of the motor to be driven out of the first motor and the second motor during the skew correction operation of said print medium satisfies a condition indicating that the skew has been removed, the process proceeds to the next operation to end the skew operation, printing device you wherein a.   A feeding roller for feeding the print medium;
  A pair of transport rollers provided on the downstream side in the transport direction of the print medium from the feed roller;
  A first motor serving as a power source for the feeding roller;
  A second motor as a power source for the pair of transport rollers;
  A controller that controls the first motor and the second motor,
  The controller performs a skew removing operation for removing skew of the print medium by driving one or both of the first motor and the second motor;
  A first mode in which the feeding speed of the print medium is a first feeding speed and a second mode in which a second feeding speed is lower than the first feeding speed;
  In the first mode, the control unit shifts to the next operation when a load of a motor driven among the first motor and the second motor exceeds a first threshold during the skew removing operation. In the second mode, if the load of the motor driven among the first motor and the second motor exceeds a second threshold value smaller than the first threshold value during the skew removing operation, the next operation is performed. A printing apparatus characterized by that. A feeding roller for feeding the print medium;
A pair of transport rollers provided on the downstream side in the transport direction of the print medium from the feed roller;
A first motor serving as a power source for the feeding roller;
A second motor as a power source for the pair of transport rollers;
A controller that controls the first motor and the second motor,
The controller performs a skew removing operation for removing skew of the print medium by driving one or both of the first motor and the second motor;
When the load of the motor driven among the first motor and the second motor exceeds a threshold during the skew removal operation, the control unit ends the skew removal operation and proceeds to the next operation,
The threshold value is a first threshold value when the medium size of the print medium is a first medium size, and a second threshold value that is larger than the first threshold value when the medium size is larger than the first medium size. A printing apparatus characterized by the above.