JP2007119154A - Paper feeding device and printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make a paper feeding speed high while suppressing generation of large collision sound by nip member such as a hopper and a separation pad and to stabilize a paper feed position of the paper. <P>SOLUTION: A paper feed control execution means 93 accelerates a first paper feeding roller 12 to a predetermined nip speed to abut the nip member 13 on the first paper feeding roller 12 and after the abutment, it accelerates the first paper feeding roller 12 again. A paper detection means 51 detects the paper P after the re-acceleration. Further, the paper feed control execution means 93 finishes drive control at a predetermined control distance after the paper detection means 51 detects the paper P. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a paper feeding device and a printer.

  Patent Document 1 discloses a printer having a sheet feeding device. In the printer described in Patent Document 1, a sheet on a paper tray is pinched by a hopper, a separation pad, and a paper feed roller, and the sandwiched paper is conveyed from the paper tray by rotation of the paper feed roller. Further, the paper that is sandwiched between a pair of transport rollers provided between the paper feed roller and the print head and transported from the paper tray is supplied to the print head.

JP 2001-247225 A (FIG. 10, detailed description of the invention, etc.)

  In the paper feeding device described in Patent Document 1, it is possible to shorten the paper feeding time by increasing the rotation speed of the paper feeding roller and the conveying roller pair. However, when the rotation speeds of the paper feed roller and the transport roller pair are increased, there are the following problems.

  In order to sandwich the paper on the paper discharge tray with the paper feed roller, the hopper and the separation pad come into contact with and separate from the paper feed roller. Generally, the hopper and the separation pad are subjected to a force that is constantly pushed up by a hopper spring that is compressed and disposed on the back side of the popper. Then, for example, when the idle roller is separated from between the paper feed roller and the separation pad, or the gap cam that rotates integrally with the paper feed roller is separated from the hopper and the separation pad, the hopper and the separation pad are raised. And abuts against the paper feed roller.

  When the hopper and separation pad rise and come into contact with the paper feed roller, a collision sound is generated. When the rotation speeds of the paper feed roller and the transport roller pair are increased, the hopper and the separation pad rise vigorously, and a large collision sound is generated. As a result, the user of the printer is uncomfortable with a loud collision sound.

  In order to suppress the generation of such a loud sound, it is conceivable to temporarily reduce the rotation speed of the paper feed roller when the hopper or separation pad comes into contact with the paper feed tray. When acceleration / deceleration is repeated, the paper feed position at the end of paper feed control varies and becomes unstable even if the speed is managed according to a predetermined speed curve tabulated.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a paper feeding device and a printer that can increase the paper feeding speed while suppressing the generation of a large collision noise caused by a nip member such as a hopper and a separation pad, and that can stabilize the paper feeding position. And

  A sheet feeding device according to the present invention includes a first sheet feeding roller that conveys sheets from a sheet feeding tray and a sheet feeding tray that is in contact with the first sheet feeding roller during sheet feeding and between the first sheet feeding roller. The nip member that sandwiches the sheet of paper and the first paper feed roller are accelerated to a predetermined nip speed to bring the nip member into contact with the first paper feed roller, and after that contact, the first paper feed roller is accelerated again. A control execution unit; and a sheet detection unit that is disposed downstream in the conveyance direction of the sheet conveyed from the sheet feeding tray and detects the sheet after the first sheet feeding roller is re-accelerated. Then, the paper feed control execution means ends the drive control at a predetermined control distance when the paper detection means detects the paper.

  If this configuration is adopted, the nip member comes into contact with the first paper feed roller while the first paper feed roller is rotating at a predetermined nip speed. Therefore, the sound generated when the nip member comes into contact with the first paper feed roller is smaller than, for example, when the nip member rotates at an accelerated speed thereafter. In addition, after the contact, control is performed at a speed faster than a predetermined nip speed, so that the paper feed speed is increased.

  The paper detection means detects the paper after accelerating from a predetermined nip speed of the first paper feed roller, and the paper feed control execution means performs the first control at a predetermined control distance based on the paper detection of the paper detection means. The drive control of the paper feed roller is terminated. Accordingly, the position of the paper when the paper feeding is completed is stabilized at the target paper feeding position with reference to the paper detection position of the paper detection means.

  In addition to the configuration of the above-described invention, a sheet feeding device according to the present invention includes a second sheet feeding roller that conveys a sheet conveyed from a sheet feeding tray by a first sheet feeding roller to a predetermined sheet feeding position, Storage means for storing a table for decelerating and stopping the speeds of the paper feed roller and the second paper feed roller in stages. Then, when the paper detection means detects the paper, the paper feed control execution means starts the deceleration control whose speed is managed by the table and ends the drive control.

  If this configuration is adopted, the speed of the deceleration period from the detection of the sheet by the sheet detection unit to the end of the drive control is managed by the table, and the deceleration control is performed in stages. Therefore, it is possible to prevent the first paper feed roller and the second paper feed roller from rotating too much when stopped, and the paper position when the paper feed is completed is stabilized.

  A sheet feeding device according to the present invention includes a second sheet feeding roller that conveys a sheet conveyed from a sheet feeding tray by a first sheet feeding roller to a predetermined sheet feeding position, in addition to the components of the invention described above. The hopper table, the first paper feed roller, and the second paper feed roller that are stopped after accelerating the one paper feed roller and the second paper feed roller to a predetermined nip speed are accelerated to the maximum feed speed that is faster than the predetermined nip speed. Storage means for storing a heading table that decelerates and stops the speed stepwise later and a continuous drive table that accelerates the first paper feed roller and the second paper feed roller from a predetermined nip speed to a maximum feed speed And having. The paper feed control execution means accelerates the first paper feed roller and the second paper feed roller to a predetermined nip speed by the hopper table and accelerates to the maximum feed speed by the continuous drive table. Is detected, the deceleration control in which the speed is managed by the heading table is started, and the drive control is ended.

  If this configuration is adopted, the paper is fed to the printing area in a state where the conveyance speed is managed by the hopper table, the continuous drive table, and the heading table. In addition, the sheet conveyance speed and the sheet feeding position are controlled by stepwise deceleration control with reference to sheet detection by the sheet detection means. Therefore, it is possible to prevent the first paper feed roller and the second paper feed roller from rotating too much when stopped, and the paper position when the paper feed is completed is stabilized.

  The printer according to the present invention executes printing at a predetermined paper feeding position targeted by the paper feeding device with respect to the paper feeding device having each configuration according to the above-described invention and the paper fed by the paper feeding device. Printing control execution means.

  By adopting this configuration, it is possible to feed and print a sheet at a high speed while suppressing a sound generated when the nip member of the sheet feeding device contacts the first sheet feeding roller. In addition, the paper feed position of the paper conveyed by the paper feeding device is stable at the paper feed position where the print control execution unit executes printing, and the print control execution unit applies the paper stably conveyed to the accurate position. You can print on it.

  In addition to the configuration of the invention described above, the printer according to the present invention includes a stop determination unit that determines stop of paper feeding based on detection, and a sheet feed control execution unit when it is determined that the stop determination unit is stopped. And a next control determination unit that selects one control execution unit to be executed next from a plurality of control execution units including the print control execution unit and instructs the selected control execution unit to execute It is.

  By adopting this configuration, it is possible to execute each control in order while confirming that the first paper feed roller or the like is stopped based on the detection. Therefore, the next control is not started in a state where the first paper feed roller or the like is not stopped, and high-quality printing as expected can be executed.

  In addition, the paper feed control execution means conveys the paper in the paper feed tray to the paper feed position based on a single execution instruction from the next control determination means. Therefore, for example, compared with a case where the sheet feed control execution unit executes the nip control and the sheet feed control up to the sheet feed position separately based on separate execution instructions from the next control determination unit, for example, Without stopping determination based on detection during the stop period, the series of paper feed control can be completed at a very high speed, and the print control execution means can transport the paper to the paper feed position where printing is performed. it can.

  Hereinafter, a sheet feeding device and a printer according to an embodiment of the present invention will be described with reference to the drawings. The printer will be described by taking as an example a so-called inkjet printer that transports a sheet, which is a kind of print medium, from a paper feed tray to a paper discharge tray and ejects ink onto the transported sheet. The paper feeding device will be described as a part of the ink jet printer.

  FIG. 1 is a front view showing a schematic mechanism of a printer 1 according to an embodiment of the present invention. FIG. 2 is a perspective view showing a schematic mechanism of the printer of FIG.

  The printer 1 includes a transport mechanism that transports the paper P placed on the paper feed tray 10 to the paper discharge tray 11, and an ink discharge mechanism that discharges ink onto a print medium such as the paper P transported by the transport mechanism. Have.

  The transport mechanism includes an LD roller 12 as a first paper feed roller, a hopper 1313 as a nip member, a paper guide 14, a PF roller 15 as a second paper feed roller, a platen 16, a paper discharge roller 17, and the like.

  The hopper 13 is disposed at the lower end of the paper feed tray 10. The hopper 13 and the paper feed tray 10 form a flat surface on which the paper P can be placed. The hopper 13 and the paper feed tray 10 are arranged in an inclined posture with the hopper 13 side being the lower side. As a result, the paper P placed on the paper feed tray 10 is positioned on the hopper 13. Further, the hopper 13 is disposed at a joint portion with the paper feed tray 10 so as to be rotatable about a direction substantially perpendicular to the paper surface of FIG.

  The LD roller 12 is formed in a substantially D-shaped side surface with a cylindrical side portion cut out. The LD roller 12 is disposed on a rotating shaft 18 disposed in a direction substantially perpendicular to the paper surface of FIG. A gap cam 19 is further disposed on the rotary shaft 18. The gap cam 19 has a large-diameter portion that is slightly larger than the outer periphery of the LD roller 12 and a small-diameter portion that is slightly smaller than the outer periphery of the LD roller 12. The large-diameter portion of the gap cam 19 is provided, for example, corresponding to the cutout portion of the LD roller 12. The remaining part is a small diameter part. Further, a recess is formed in the large diameter portion of the gap cam 19.

  FIG. 3 is an explanatory view of the nip operation by the LD roller 12 and the hopper 13 in FIG. As shown in FIG. 3A, the LD roller 12 and the gap cam 19 are disposed in the vicinity of the hopper 13. A hopper spring 21 is disposed on the back surface of the hopper 13. Due to the force of the hopper spring 21, a force toward the LD roller 12 is urged to the hopper 13. Thus, when the printer 1 is stopped, the convex portion 13 a formed at the lower end portion of the hopper 13 fits into the concave portion 19 c of the gap cam 19 as shown in FIG.

  From this state, for example, when the LD roller 12 rotates clockwise as indicated by an arrow in FIG. 3A, the lower end edge of the hopper 13 is disengaged from the recess 19c of the gap cam 19, and the large diameter of the gap cam 19 is increased. It contacts the part 19a. Further, when the LD roller 12 rotates clockwise, as shown in FIG. 3B, the lower end edge of the hopper 13 is separated from the large diameter portion 19a of the gap cam 19 and is moved to the small diameter portion 19b of the gap cam 19. Come into contact. At this time, the distance between the hopper 13 and the LD roller 12 is minimized, and when there is a sheet P on the hopper 13, the sheet P comes into contact with the LD roller 12. As a result, the paper P on the paper feed tray 10 is nipped by the LD roller 12 and the hopper 13.

  When the LD roller 12 further rotates clockwise from the state of FIG. 3B, the paper P that contacts the LD roller 12 is conveyed in the lower left direction in FIG. 3 as the LD roller 12 rotates. The paper P is transported from the paper feed tray 10. When the LD roller 12 makes one rotation, as shown in FIG. 3A, the convex portion 13a formed at the lower end portion of the hopper 13 stops in a state where the convex portion 13a is fitted in the concave portion 19c of the gap cam 19.

  Returning to FIG. The paper guide 14, the PF roller 15, and the paper discharge roller 17 of the transport mechanism are arranged in a line along the print medium transport path between the LD roller 12 and the paper discharge tray 11. Hereinafter, the transport path of the paper P from the paper feed tray 10 to the paper discharge tray 11 is referred to as a print medium transport path, the paper feed tray 10 side is referred to as the upstream side in the print medium transport direction, and the paper discharge tray 11 side is referred to as the print medium transport. It is called the direction downstream side.

  The sheet guide 14 is a plate-shaped member whose upper surface is substantially flat.

  The PF roller 15 is a substantially cylindrical roller. A driven roller 23 having a substantially cylindrical shape is disposed on the upper side of the PF roller 15. The PF roller 15 and the driven roller 23 are rotatably arranged with a direction substantially perpendicular to the paper surface of FIG.

  The platen 16 has a substantially flat plate member and a plurality of ribs 16a formed on the upper surface thereof.

  The paper discharge roller 17 is a substantially cylindrical roller. A driven roller 24 having a substantially cylindrical shape is disposed above the paper discharge roller 17. The paper discharge roller 17 and the driven roller 24 are rotatably disposed around a direction substantially perpendicular to the paper surface of FIG.

  An ink ejection mechanism is disposed on the upper side of the transport mechanism having the above configuration. The ink ejection mechanism mainly includes a carriage shaft 31, a carriage 32, an ink tank 33, a recording head 34, and the like.

  The carriage shaft 31 is a cylindrical shaft member. The carriage shaft 31 is disposed above the PF roller 15 so as to extend in a direction substantially perpendicular to the paper surface of FIG.

  The carriage 32 is held by the carriage shaft 31 and is located above the platen 16. The carriage 32 is movable along the axial direction of the carriage shaft 31. A recording head 34 having a plurality of ink discharge nozzles 35 (not shown) is disposed on the lower surface of the carriage 32. A region between the scanning range of the recording head 34 and the platen 16 is a printing region for ejecting ink onto the paper P. This print area is a predetermined paper feed position which is a target by the printer 1 of this embodiment.

  The carriage 32 is provided with an ink tank 33. The ink stored in the ink tank 33 is supplied to the plurality of ink discharge nozzles 35. A piezo element that is deformed by an applied voltage is disposed in each ink discharge nozzle 35. When the piezoelectric element is deformed, ink is ejected from each ink ejection nozzle 35.

  FIG. 4 is a diagram showing a main hardware configuration of a control system for controlling the printer 1 mechanism of FIG. FIG. 5 is a block diagram of a control system implemented in the printer 1 of FIG. The control system of the printer 1 has an external interface (I / F) 41 to which the host computer 2 is connected.

  The external I / F 41 has a connector (not shown) to which a USB (Universal Serial Bus) cable, a printer cable, a SCSI (Small Computer System Interface) cable, and the like can be connected. The external I / F 41 receives print data from the host computer 2 via this connector. The external I / F 41 may be connected to the host computer 2 by wireless communication by Bluetooth, wireless LAN (Local Area Network), or the like.

  The external I / F 41 is connected to an ASIC (Application Specific Integrated Circuit) 42. The ASIC 42 includes a CPU (Central Processing Unit), a RAM (Random Access Memory), a programmable ROM (Read Only Memory), a timer, and the like (not shown) based on a program stored in the programmable ROM. A computer that operates in a predetermined manner.

  The ASIC 42 includes an unillustrated I / O (Input / Output) port, an ADC (Analog to Digital Converter), a DAC (Digital to Analog Converter), and the like. The I / O port is used for input / output of digital signals. The ADC samples the waveform of the input signal at a predetermined cycle. The DAC outputs a signal that changes to a level corresponding to a set value at a predetermined sampling period.

  To the I / O port of the ASIC 42, a PF (paper feed) sensor 51, a linear encoder 52, a rotary encoder 53, and the like serving as a sheet detecting means for detecting the state of the printer 1 are connected. Other sensors connected to the ASIC 42 include, for example, a PW (paper wide) sensor that detects an edge of the paper P, a PG (paper gap) sensor that detects a gap between the recording head 34 and the paper P, and a CDR ( CD Recordable) tray sensor, CDR guide sensor, and the like.

  The PF sensor 51 detects the leading edge or the trailing edge of the paper P that passes over the paper guide 14. As shown in FIG. 1, the PF sensor 51 includes a transmissive optical sensor 51 a and a retract lever 51 b that rotates depending on the presence or absence of the paper P. The retract lever 51b is normally disposed so that the lower end thereof is in contact with the paper guide 14. When the paper P passes over the paper guide 14, the retract lever 51b is pushed up by the paper P passing therethrough and rotates. The upper end portion of the retract lever 51b is separated from the transmissive optical sensor 51a. The transmissive optical sensor 51a outputs a light reception signal that changes according to the presence or absence of the retract lever 51b to the I / O port of the ASIC 42.

  The linear encoder 52 detects the position and speed of the carriage 32 in the main scanning direction. The linear encoder 52 includes an elongated reflecting plate 52a and a reflective optical sensor 52b. As shown in FIG. 1, the reflective optical sensor 52 b is disposed on the surface of the carriage 32 on the LD roller 12 side. As shown in FIG. 2, the reflection plate 52a is disposed on the inner surface of the carriage unit that holds the carriage shaft 31 so as to face the scanning range of the reflection optical sensor 52b. A pattern in which white patterns and black patterns are alternately arranged along the movement direction of the carriage 32 is printed on the reflection plate 52a. When the carriage 32 moves, the amount of light received by the reflective optical sensor 52b changes according to the pattern of the reflection plate 52a. The reflection type optical sensor 52b sends a light reception signal that changes according to the change in the amount of received light to the ASIC 42. Output to the I / O port.

  The rotary encoder 53 detects the transport speed and transport amount of the paper P. The rotary encoder 53 includes a disk 53a and a transmissive optical sensor 53b. A plurality of slits 53c are arranged along the outer periphery of the disk 53a on the outer periphery of the disk 53a. The disc 53 a is integrated with the PF roller 15 and rotates together with the PF roller 15. The transmissive optical sensor 53b is disposed so as to detect the outer peripheral portion of the disc 53a. When the circular plate 53a rotates together with the PF roller 15, the amount of light received by the transmissive optical sensor 53b changes according to the arrangement pattern of the slits 53c, and the transmissive optical sensor 53b changes according to the change in the amount of received light. Is output to the I / O port of the ASIC 42.

  In addition, a recording head control circuit 61, a CR (carriage) motor driver 62, a PF motor driver 63, and the like are connected to the ASIC 42. The recording head control circuit 61 applies a voltage to the plurality of piezo elements disposed in the plurality of ink ejection nozzles 35 of the recording head 34 based on the control signal from the ASIC 42. The CR motor driver 62 drives the CR motor 64 to rotate based on a control signal from the ASIC 42. The PF motor driver 63 rotationally drives the PF motor 65 based on a control signal from the ASIC 42.

  The CR motor 64 and the PF motor 65 are, for example, DC motors. The rotational speed of the DC motor is accelerated and decelerated by controlling the magnitude of the current flowing through it, for example. The CR motor 64 and the PF motor 65 may be a pulse motor such as a stepping motor.

  As shown in FIG. 2, the CR motor 64 rotationally drives a rotating belt 66 to which the carriage 32 is fixed. The carriage 32 scans the print area according to the rotation of the CR motor 64.

  The PF motor 65 rotationally drives the LD roller 12, the PF roller 15, and the paper discharge roller 17 via a predetermined drive transmission mechanism. This drive transmission mechanism transmits the driving force so that the peripheral speed of the rotating LD roller 12, the peripheral speed of the PF roller 15, and the peripheral speed of the paper discharge roller 17 are substantially uniform. Further, the drive transmission mechanism transmits a driving force for the LD roller 12 so as to pause the rotation of the LD roller 12 every rotation.

  In addition, a system bus 71 is connected to the ASIC 42. The system bus 71 is connected to a CPU 72 separate from the ASIC 42, a memory 73 as a storage means, a RAM 74, a timer 75, and the like. The CPU 72, the memory 73, the RAM 74, and the timer 75 may be formed as separate chips or may be integrated into one chip.

  The memory 73 stores a firmware program 81 and various control data. The control data includes, for example, a hopper table 82, a head setting table 83, a continuous drive table 84, and the like. Note that the firmware program 81 and control data stored in the memory 73 may be stored in the memory 73 before the shipment of the printer 1 or may be stored in the memory 73 after the shipment of the printer 1. The firmware program 81 and control data stored in the memory 73 after shipment of the printer 1 are downloaded from a computer-readable recording medium such as a CD-ROM, or downloaded via a transmission medium such as an electric communication line. Anything can be used. Further, only part of the firmware program 81 and control data stored in the memory 73 may be updated and stored after shipment of the printer 1.

  FIG. 6 is an explanatory diagram showing the data structure of the hopper table 82 in FIG. The hopper table 82 stores a predetermined control target speed curve of the PF motor 65 as a plurality of discrete speed data. The head portion of the plurality of speed data is data for acceleration control at an acceleration of a predetermined value or less from speed 0 to a predetermined nip speed. The central portion of the plurality of speed data is data for constant speed control at a predetermined nip speed. The rear end portion of the plurality of speed data is data for performing deceleration control from a predetermined nip speed to speed 0 at an acceleration equal to or lower than a predetermined value.

  The predetermined nip speed is lower than the maximum control speed of the PF motor 65, and is determined as follows, for example. As shown in FIG. 3A, the hopper 13 in contact with the large diameter portion 19a of the gap cam 19 is in contact with the small diameter portion 19b as shown in FIG. Become. When the hopper 13 moves away from the large diameter portion 19a and comes into contact with the small diameter portion 19b, a collision sound is generated. The collision noise increases as the rotational speed of the LD roller 12 increases. The predetermined nip speed is determined, for example, as a speed at which the impact sound is suppressed to such a level that the user does not feel uncomfortable.

  FIG. 7 is an explanatory diagram showing the data structure of the heading table 83 in FIG. In the heading table 83, the PF motor 65 is accelerated from a speed of 0 to the maximum control speed of the PF motor 65 at an acceleration equal to or lower than a predetermined value, and then the control target speed curve for performing constant speed control at the maximum control speed is discrete. A plurality of speed data and a plurality of discrete speed data of a control target speed curve for performing deceleration control at an acceleration of a predetermined value or less from the maximum control speed to a speed of 0 are stored. In addition to this, the heading table 83 stores deceleration control distance information 83a. The deceleration control distance information 83a is information indicating a distance necessary for control to decelerate from the maximum control speed to the speed 0.

  FIG. 8 is an explanatory diagram showing the data structure of the continuous drive table 84 in FIG. In the continuous drive table 84, a control target speed curve for accelerating the PF motor 65 from a predetermined nip speed to a maximum control speed of the PF motor 65 at an acceleration of a predetermined value or less is stored as a plurality of discrete speed data. The

  The CPU 72 reads the firmware program 81 stored in the memory 73 into the RAM 74 and executes it. Accordingly, as shown in FIG. 5, the printer 1 includes a stop determination unit 91 as a stop determination unit, a next control determination unit 92 as a next control determination unit, and a paper feed control execution unit 93 as a paper feed control execution unit. An ink discharge control execution unit 94, a paper feed control execution unit 95, an error control execution unit 96, and the like are realized as print control execution means.

  The stop determination unit 91 determines whether or not the printer 1 is in a stopped state. Specifically, for example, the stop determination unit 91 determines whether or not the light receiving element output from the rotary encoder 53 to the ASIC 42 and the light receiving signal output from the light receiving element of the linear encoder 52 to the ASIC 42 for a predetermined time. When there is no change (for example, several microseconds to several hundred milliseconds), it is determined that the printer 1 is in a stopped state.

  The paper feed control execution unit 93 executes control for transporting the paper P placed on the paper feed tray 10 to the printing area. Specifically, the paper feed control execution unit 93 instructs the rotational speed of the PF motor 65 to the DC unit 101 realized in the ASIC 42 using, for example, the hopper table 82, the heading table 83, and the like. .

  The ink discharge control execution unit 94 executes ink discharge control for the paper P supplied to the printing area. Specifically, the ink discharge control execution unit 94 instructs, for example, the rotation speed of the CR motor 64 according to a predetermined speed curve to the DC unit 101, and ink for one scan of the carriage 32 based on the print data. Outputs discharge control data.

  The paper feed control execution unit 95 executes transport control of the paper P being fed to the print area. Specifically, the paper feed control execution unit 95 instructs, for example, the rotation speed of the PF motor 65 according to a predetermined speed curve to the DC unit 101.

  The error control execution unit 96 executes control for eliminating the abnormal state of the printer 1. For example, when the paper feeding is not normally performed, the error control execution unit 96 continuously causes the DC unit 101 to keep the PF motor 65 continuous for a predetermined time or more so as to discharge all the paper P on the print medium conveyance path. To drive.

  The DC unit 101 outputs various signals to the recording head control circuit 61, the CR motor driver 62, and the PF motor driver 63 using, for example, the DAC, I / O port, or the like of the ASIC 42. The DC unit 101 updates signals to be output to the CR motor driver 62 and the PF motor driver 63 every predetermined short cycle (for example, several tens of microseconds). Thus, the recording head 34, the CR motor 64, and the PF motor 65 are controlled in accordance with instructions from the paper feed control execution unit 93, the ink discharge control execution unit 94, the paper feed control execution unit 95, the error control execution unit 96, and the like. .

  The next control determination unit 92 instructs the sheet feeding control execution unit 93, the ink discharge control execution unit 94, the paper feed control execution unit 95, the error control execution unit 96, and the like to execute. When the process instructed to execute is completed, the next control determination unit 92 determines a process to be executed next, and instructs the control execution unit to execute the determined process. The next control determination unit 92 basically instructs one control execution unit to execute at a time. The next control determination unit 92 does not instruct execution to a plurality of control execution units at the same time.

  Next, the operation of the printer 1 according to the first embodiment having the above configuration will be described.

  FIG. 9 is a timing chart showing control from paper feeding to printing of the printer 1 according to the first embodiment.

  When a power button (not shown) of the printer 1 is operated and the printer 1 is activated, the printer 1 includes a DC unit 101, a stop determination unit 91, a next control determination unit 92, and a paper feed control execution unit as shown in FIG. 93, an ink discharge control execution unit 94, a paper feed control execution unit 95, an error control execution unit 96, and the like are realized. When the external I / F 41 receives print data from the host computer 2 connected thereto, the next control determination unit 92 of the printer 1 starts printing based on the print data.

  The host computer 2 generates, for example, an image for printing a predetermined image on a predetermined paper P, converts the print image into an image for each ink color, performs halftone processing on each ink color image, Rasterize color halftone image. The host computer 2 may transmit the data after the rasterization process to the printer 1 as print data.

  In addition to this, for example, the host computer 2 may transmit image data to be printed and printing conditions such as paper P and layout to the printer 1. In this case, in the printer 1, the ASIC 42 may generate the print data after the rasterizing process from the received image data and printing conditions.

  When the next control determination unit 92 starts printing, it first determines whether or not the printer 1 is in a printable state. Specifically, for example, the next control determination unit 92 acquires detection information based on detection signals from the PF sensor 51, the linear encoder 52, the rotary encoder 53, and the like from the ASIC 42, and determines whether or not these detection information are normal. Judging.

  When it is determined that the printer 1 is in a printable state, the next control determination unit 92 instructs the paper feed control execution unit 93 to execute. The next control determination unit 92 instructs, for example, continuous paper feed control using the hopper table 82, the continuous drive table 84, and the heading table 83. The paper feed control execution unit 93 starts continuous paper feed control for transporting the paper P on the paper feed tray 10 without stopping to the printing area.

  In the continuous paper feed control, the paper feed control execution unit 93 first reads the top data of the hopper table 82 and instructs the DC unit 101 about the target control speed of the read data.

  When the first target control speed is instructed, the DC unit 101 and the PF motor driver 63 start to rotate the PF motor 65. The rotational driving force of the PF motor 65 is transmitted to the LD roller 12, the PF roller 15, and the paper discharge roller 17 through a drive transmission mechanism. The LD roller 12, the PF roller 15, and the paper discharge roller 17 start rotating according to the rotation of the PF motor 65.

  The rotary encoder 53 outputs a pulse according to the rotation of the PF motor 65. The DC unit 101 and the PF motor driver 63 control the rotation speed of the PF motor 65 so that the speed detected by the rotary encoder 53 becomes the target control speed instructed by the DC unit 101.

  After instructing the first target control speed to the DC unit 101, the paper feed control execution unit 93 reads the next data of the hopper table 82 at a predetermined cycle, and instructs the DC unit 101 about the target control speed of the read data. To do. The target control speed instructed to the DC unit 101 is changed at a predetermined cycle. When the target control speed is changed, the DC unit 101 and the PF motor driver 63 control the rotation speed of the PF motor 65 so that the speed detected by the rotary encoder 53 becomes the changed target control speed.

  Thereby, the DC unit 101 and the PF motor driver 63 rotate the rotation speed of the PF motor 65 so that the detection speed of the rotary encoder 53 changes at a speed according to a plurality of data stored in order from the top of the hopper table 82. To control. The rotation speed of the PF motor 65 is accelerated from a speed of 0 to a predetermined nip speed in accordance with data at the head portion of the hopper table 82, as shown in a period M1 in FIG. Thereafter, the rotational speed of the PF motor 65 is controlled at a constant speed at a predetermined nip speed in accordance with the data of the central portion of the hopper table 82, as shown in a period M2 in FIG.

  When the LD roller 12 and the gap cam 19 rotate in the period M2 in which the rotation speed of the PF motor 65 is controlled at a constant nip speed, the hopper 13 is moved from the large diameter portion 19a of the gap cam 19. It separates and contacts the small diameter part 19b. The paper P on the paper feed tray 10 is nipped by the hopper 13 and the LD roller 12 and begins to be conveyed according to the rotation of the LD roller 12.

  When the continuous paper feed control is instructed, the paper feed control execution unit 93 performs constant speed control of the PF motor 65 at the nip speed according to the data of the hopper table 82 and then reads a plurality of data of the continuous drive table 84. The control based on the data of the continuous drive table 84 is started. The continuous drive table 84 stores data of a control target speed curve for accelerating from a predetermined nip speed to the maximum control speed of the PF motor 65. The paper feed control execution unit 93 reads a plurality of data in the continuous drive table 84 in order from the head in a predetermined cycle, and instructs the DC unit 101 of the target control speed of the read data. The rotation speed of the PF motor 65 is accelerated from a predetermined nip speed to a maximum control speed as indicated by a period M3 in FIG.

  After reading up to the last data of the continuous drive table 84 and controlling the acceleration of the rotation speed of the PF motor 65 to the maximum control speed, the paper feed control execution unit 93 sends the maximum to the DC unit 101 as shown in a period M4 in FIG. Monitoring of the detection signal of the PF sensor 51 is started while the control speed is instructed.

  The sheet P conveyed according to the rotation of the LD roller 12 pushes up the retract lever 51 b of the PF sensor 51. The detection signal of the PF sensor 51 changes from the absence of the paper P to the presence of the paper P. The paper feed control execution unit 93 may read the constant speed control data of the cueing table 83 in order to instruct the DC unit 101 of the maximum control speed.

  When the PF sensor 51 detects the paper P, the paper feed control execution unit 93 reads the deceleration control distance information 83a from the heading table 83. The paper feed control execution unit 93 adds a predetermined constant pulse number corresponding to the distance of the deceleration control distance information 83a to the cumulative pulse number of the rotary encoder 53 at the time of the change, and sets a timing at which the cumulative pulse number of the addition result is obtained. Then, it is determined as the start timing of deceleration control.

  After determining the start timing of the deceleration control, the paper feed control execution unit 93 counts the cumulative number of pulses of the rotary encoder 53. When the cumulative number of pulses of the rotary encoder 53 reaches the determined cumulative number of pulses, the paper feed control execution unit 93 reads the head data of the control target speed curve that decelerates from the maximum control speed to the speed 0 from the heading table 83. Instruct the DC unit 101 of the target control speed of the read data. Further, the paper feed control execution unit 93 reads the next data from the heading table 83 every predetermined cycle, and instructs the DC unit 101 of the target control speed of the read data.

  As shown in the period M5 in FIG. 9, the PF motor 65 decelerates from the maximum control speed based on the deceleration data of the heading table 83 and stops. The detected rotational speed of the rotary encoder 53 is also decelerated step by step following the speed change, and finally becomes the speed “0”. The paper feed control execution unit 93 instructs the control speed “0” based on the last deceleration data in the heading table 83 and then ends the continuous paper feed control.

  In this period M4 and M5, the paper P that is conveyed according to the rotation of the LD roller 12 and pushes up the retract lever 51b of the PF sensor 51 is nipped by the PF roller 15 and its driven roller 23, and the PF roller 15 rotates by a predetermined amount. When you stop. The stop position of the paper P is stable. Further, the leading end portion of the paper P is accurately positioned in the printing area.

  When the continuous paper feed control by the paper feed control execution unit 93 is completed, the rotation of the PF roller 15 is stopped. The rotary encoder 53 stops outputting pulses. The stop determination unit 91 confirms that the detection signal of the rotary encoder 53 does not change over a predetermined time, and determines that the printer 1 is in the stop state.

  When the continuous paper feed control by the paper feed control execution unit 93 is completed and the stop determination unit 91 determines that the printer 1 is in the stopped state, the next control determination unit 92 determines whether or not the printer 1 is in a printable state. The control execution unit to be executed next is determined according to the determination. For example, when it is determined that the printer 1 has an abnormality and is not in a printable state, the next control determination unit 92 instructs the error control execution unit 96 to execute. The error control execution unit 96 drives the PF motor 65 continuously for a predetermined time, for example, and discharges the paper P on the print medium conveyance path to the paper discharge tray 11.

  When it is determined that the printer 1 is in a printable state, the next control determination unit 92 causes the ink discharge control execution unit 94 to execute ink discharge control in order to discharge ink onto the paper P fed to the print area. Instruct.

  The ink discharge control execution unit 94 instructs the target speed of the carriage 32 to the DC unit 101. The DC unit 101 and the CR motor driver 62 rotate the CR motor 64. Due to the rotational driving force of the CR motor 64, the carriage 32 starts to move in a direction perpendicular to the paper surface of FIG. The moving speed of the carriage 32 is controlled to a predetermined constant speed as shown in the center portion of the period N1 in FIG.

  The ink ejection control execution unit 94 instructs the DC unit 101 to eject ink after the speed of the carriage 32 detected by the linear encoder 52 reaches a predetermined speed. The DC unit 101 and the recording head control circuit 61 apply a voltage having a waveform according to the print data to the plurality of piezoelectric elements of the recording head 34. Ink is ejected from the plurality of ink ejection nozzles 35 of the recording head 34 in accordance with the applied voltage waveform. The ejected ink adheres to the leading end portion of the paper P being fed to the printing area. When the carriage 32 performs one scan, the ink for the one scan adheres to the paper P being fed to the print area. When the ink ejection is finished, the ink ejection control execution unit 94 stops the carriage 32.

  When the ink discharge control by the ink discharge control execution unit 94 is completed, the stop determination unit 91 determines whether or not the printer 1 is in a stopped state. When the stop determination unit 91 confirms that the detection signal from the linear encoder 52 does not change for a predetermined time, the stop determination unit 91 determines that the printer 1 is in a stopped state.

  When ink discharge control for one scan by the ink discharge control execution unit 94 is completed and the stop determination unit 91 determines that the printer 1 is in a stopped state, the next control determination unit 92 determines whether the printer 1 is ready for printing. The control execution unit to be executed next is determined according to the determination. When it is determined that the printer 1 is in a printable state, the next control determination unit 92 instructs the paper feed control execution unit 95 to execute.

  The paper feed control execution unit 95 executes control for feeding the paper P being fed to the printing area by a predetermined amount. The paper feed control execution unit 95 outputs a speed instruction of the PF motor 65 according to a predetermined speed curve to the DC unit 101. The rotational speed of the PF motor 65 is controlled so that the speed determined based on the detection pulses of the DC unit 101, the PF motor driver 63, and the rotary encoder 53 becomes the instructed speed.

  As a result, as shown in the periods M11 to M13 in FIG. 9, the PF motor 65 is accelerated to a predetermined speed, controlled at a constant speed, and then stopped. The paper P fed to the printing area is conveyed by a predetermined amount. The predetermined amount conveyed by the paper feed control may be a distance corresponding to the arrangement width of the plurality of ink discharge nozzles 35 formed in the recording head 34 in the print medium conveyance direction, for example.

  When one paper feed control by the paper feed control execution unit 95 is completed, the stop determination unit 91 determines that it is in a stopped state, and the next control determination unit 92 determines a control execution unit to be executed next. The next control determination unit 92 instructs the ink discharge control execution unit 94 to execute ink discharge control for the second scan.

  Thereafter, each time the ink ejection control execution unit 94 completes the ink ejection control for one scan, the next control determination unit 92 instructs the paper feeding control execution unit 95 to execute the paper feeding control for one time, and the paper Whenever the paper feed control for one time by the feed control execution unit 95 is completed, the ink discharge control execution unit 94 instructs to execute the ink discharge control for one scan. As a result, ink is attached to the paper P fed to the print area for each scan, and an image based on the print data is printed.

  Further, when there is no unprocessed print data or printing for one page is completed, the next control determination unit 92 instructs the discharge control execution unit (not shown) to execute. The paper discharge control execution unit instructs the rotation speed of the PF motor 65 for paper discharge to the DC unit 101. The DC unit 101 and the PF motor driver 63 rotate the PF motor 65 for a predetermined time. The paper P fed to the printing area is conveyed by the PF roller 15 and the paper discharge roller 17 and discharged to the paper discharge tray 11.

  Further, when the external I / F 41 receives print data to be continuously printed on two or more sheets P, when the next control determination unit 92 completes printing of each page other than the last page, Instead of the paper discharge control execution unit, the continuous paper supply control is instructed to the paper supply control execution unit 93. As in the case of the first sheet P, the sheet feed control execution unit 93 uses the data of the hopper table 82, the continuous drive table 84, and the heading table 83, and when the PF sensor 51 detects the sheet P, Stop at a distance. As a result, the second and subsequent sheets of paper P are fed to the printing area. The paper discharge roller 17 is rotationally driven together with the LD roller 12 and the PF roller 15 by the PF motor driver 63. Accordingly, the printed paper P that has been fed to the printing area is discharged to the paper discharge tray 11.

  As described above, in the first embodiment, when the paper P in the paper feed tray 10 is transported to the printing area, the paper feed control execution unit 93 causes the two-step mountain as shown in FIG. 9 to continue. The rotation of the LD roller 12 and the PF roller 15 is controlled by the speed curve.

  When the paper feed control execution unit 93 is controlling at the lower peak speed (nip speed), the hopper 13 contacts the small diameter part 19 b of the gap cam 19. Therefore, the opening operation sound of the hopper spring 21 that is generated when the hopper 13 contacts the small diameter portion 19b of the gap cam 19 is smaller than when the same contact is made, for example, at the higher maximum control speed. . The user of the printer 1 does not feel uncomfortable with a loud sound.

  Further, the paper feed control execution unit 93 accelerates the rotational speed of the LD roller 12 and the PF roller 15 to the maximum control speed after the hopper 13 contacts the small diameter portion 19b of the gap cam 19. Therefore, the paper P on the paper feed tray 10 is fed from the paper feed tray 10 to the print area in a short time.

  In particular, if, for example, the paper feed control execution unit 93 separately executes control by the hopper table 82 and control by the heading table 83, the stop determination unit 91 determines the stop between these controls, and the next It is necessary for the control determination unit 92 to instruct the paper feed control execution unit 93 to perform control using the cue table 83. On the other hand, in this embodiment, since the next control determination unit 92 instructs continuous drive control, the time required for this determination and instruction can be reduced, and the paper P on the paper feed tray 10 is The paper is fed from the paper feed tray 10 to the printing area in a shorter time.

  Therefore, in the printer 1 according to this embodiment, the paper feed control can be shortened while suppressing the sound generated when the hopper 13 contacts the small diameter portion 19b of the gap cam 19 to a level that does not cause discomfort. it can. By shortening the paper feed control, the time for printing on one sheet of paper P is also shortened, and as a result, the number of printable sheets per unit time can be increased. Further, the printer 1 can perform printing on the paper P that is accurately and stably fed into the printing area.

  In this embodiment, the paper feed control execution unit 93 uses the timing at which the PF sensor 51 detects the leading edge of the paper P as a reference, the deceleration control distance information 83a of the heading table 83 and the maximum control speed to the speed 0. The sheet P is decelerated and stopped using the speed data of the control target speed curve that is controlled to decelerate stepwise at an acceleration of a predetermined value or less. Therefore, the position of the paper P when the paper feeding is completed can suppress the LD roller 12 and the PF roller 15 from rotating too much when stopped, and is stabilized in the target printing area.

  In particular, the acceleration period immediately before the constant speed control period at the maximum control speed at which the PF sensor 51 detects the leading edge of the paper P is controlled so as to accelerate stepwise based on a plurality of data in the continuous drive table 84. ing. Therefore, in the constant speed control period at the maximum control speed, the conveyance speed of the paper P is stabilized from the beginning. Even when the PF sensor 51 detects the leading edge of the paper P at the timing immediately after acceleration, the PF sensor 51 can stably and accurately detect the leading edge of the paper P. As a result, the paper feed position to the print area of the paper P is also stabilized.

  In this embodiment, in order to continuously convey the paper P from the paper feed tray 10 to the printing area, the paper feed control execution unit 93 uses a hopper table 82, a continuous drive table 84, and a heading table 83. is doing. Therefore, in the memory 73, all the speed data for continuously transporting the paper P from the paper feed tray 10 to the printing area, which is necessary for this continuous driving, is stored in the hopper table 82 and the heading table 83. There is no need to memorize it separately. Continuous drive control is possible without increasing the storage area of the memory 73. Moreover, the hopper table 82 and the heading table 83 can be easily corrected individually.

  The above embodiment is an example of a preferred embodiment of the present invention, but the present invention is not limited to this, and various modifications and changes can be made without departing from the scope of the invention. is there.

  For example, in the embodiment described above, the next control determination unit 92 instructs the paper feed control execution unit 93 to perform continuous paper feed control using the hopper table 82, the continuous drive table 84, and the heading table 83. In addition to this, for example, the next control determination unit 92 separately performs control by the hopper table 82 and control by the heading table 83 on the paper feed control execution unit 93 according to, for example, the type of printing medium. You may make it indicate.

  FIG. 10 is a timing chart of a modified example showing control when the control by the hopper table 82 and the control by the heading table 83 are separately instructed to the paper feed control execution unit 93. As shown in FIG. 10, the paper feed control execution unit 93 performs acceleration, constant speed, and deceleration control by the hopper table 82, and then executes acceleration, constant speed, and deceleration control by the heading table 83.

  In the case of this modification, between the constant speed control period M2 by the hopper table 82 and the constant speed control period M4 by the heading table 83, the deceleration control period M21 up to the speed 0 and the control instruction from the next control determination unit 92 There is a waiting period M22 and an acceleration control period M23 that accelerates from speed 0 to the maximum control speed. Therefore, as apparent from comparison with FIG. 9, the period from the start of the acceleration control by the hopper table 82 to the completion of the deceleration control by the heading table 83 is longer than that in this embodiment. End up.

  In the embodiment and the modification described above, the continuous drive table 84 has a plurality of speed data of a speed curve that accelerates from the nip speed to the maximum control speed. In addition to this, for example, the continuous drive table 84 may have a plurality of speed data of a speed curve that decelerates from the nip speed and then accelerates to the maximum control speed.

  In the above-described embodiment and modification, three tables of the hopper table 82, the continuous drive table 84, and the head setting table 83 are used to convey the paper P on the paper feed tray 10 to the printing area. In addition to this, for example, the memory 73 stores speed data for acceleration control at an acceleration of a predetermined value or less from speed 0 to a predetermined nip speed, speed data for constant speed control at a predetermined nip speed, and a predetermined nip speed. Speed data for acceleration control up to the maximum control speed of the PF motor 65 at an acceleration below a predetermined value, speed data at constant speed control at the maximum control speed, and speed for deceleration control at an acceleration below the predetermined value from the maximum control speed to speed 0 The continuous drive table 84 having data may be stored, and the next control determination unit 92 may designate the continuous drive table 84 and instruct the paper feed control execution unit 93 to feed paper. In this case, by further storing the deceleration control distance information 83a in the continuous drive table 84, the paper feed control execution unit 93 is based on the paper detection of the PF sensor 51 in the constant speed control period M4 at the maximum control speed. The paper P can be fed accurately and stably to the printing area.

  In the embodiment and the modification described above, the paper feed control execution unit 93 monitors the paper detection of the PF sensor 51 in the constant speed control period M4 at the maximum control speed. In addition to this, for example, the paper feed control execution unit 93 may monitor the paper detection of the PF sensor 51 for all periods from the start of driving of the PF motor 65 to the stop thereof. In the case of this modification, for example, when the PF sensor 51 detects the paper P in a period other than the constant speed control period M4 at the maximum control speed, the paper feed control execution unit 93 drives the PF motor 65 for a predetermined period to perform printing. A predetermined error process for discharging the paper P on the medium conveyance path to the paper discharge tray 11 may be executed. The target control speed for this error control may be stored in the continuous drive table 84, for example. Thus, when an error occurs, the printer 1 can immediately start error control without waiting for the processing of the error control execution unit 96 after the control of the printer 1 is stopped.

  In the above-described embodiment and modification, the hopper 13 contacts the large diameter portion 19 a and the small diameter portion 19 b of the gap cam 19. In addition, for example, the hopper 13 may be in contact with the large diameter portion 19 a of the gap cam 19 and the LD roller 12. Further, instead of the hopper 13, a retard roller or the like may be brought into contact with or separated from the LD roller 12 or the like.

  In the embodiment and the modification described above, the PF sensor 51 is used as a sensor for detecting the paper P conveyed from the paper feed tray 10 to the printing area. In addition to this, for example, a PW sensor provided in the carriage 32 for detecting the edge of the paper P may be used as a sensor for detecting the paper P.

  In the embodiment and the modification described above, the next control determination unit 92 instructs the next control execution unit to execute after the stop determination of the printer 1 based on the detection of the stop determination unit 91. In addition to this, for example, when synchronization is ensured by design or the like, the next control determination unit 92 completes the execution of the previous control execution unit immediately after the execution of the previous control execution unit is completed. Prior to this, execution may be instructed to the next control execution unit.

  In the above-described embodiment and modification, the paper P on the paper feed tray 10 is transported to the printing area, then is transported by a predetermined amount, and finally transported to the paper discharge tray 11. In addition to this, for example, the paper P on the paper feed tray 10 may be transported all at once to the paper discharge tray 11 without stopping in the printing area.

  In the above-described embodiment and modification, ink is ejected onto the paper P in the printing region. In addition to this, for example, toner particles may be attached to the paper P in the printing region, or a printing process may be performed on photographic paper as a printing medium.

  In the above-described embodiments and modifications, the LD roller 12 is driven by the PF motor 65 to synchronize with the PF roller 15 and the like, but a motor dedicated to the LD roller is separate from the PF motor 65. You may make it provide. In that case, the initial paper feed control based on the hopper table 82 is mainly performed for the dedicated motor of the LD roller 12, and the paper feed control based on the heading table 83 is performed for the PF motor 65. Become.

  The present invention can be applied to all apparatuses having a sheet feeding apparatus, and is particularly suitable for use in an ink jet printer that prints print data from a host computer.

It is a block diagram which shows the main mechanisms of the printer which concerns on embodiment of this invention. FIG. 2 is a perspective view showing the main mechanism of the printer of FIG. 1. It is explanatory drawing of nip operation | movement of the printer of FIG. FIG. 2 is a block diagram illustrating a hardware configuration of a control system of the printer in FIG. 1. FIG. 2 is a block diagram illustrating functions of a control system realized in the printer of FIG. 1. It is a figure which shows the data structure of the hopper table memorize | stored in the memory of FIG. It is a figure which shows the data structure of the heading table memorize | stored in the memory of FIG. It is a figure which shows the data structure of the continuous drive table memorize | stored in the memory of FIG. 2 is a timing chart showing continuous paper feed control and the like in the printer of FIG. 10 is a timing chart of a modified example in which hopper control and head-out control are different.

Explanation of symbols

1 printer, 10 paper feed tray, 12 LD roller (first paper feed roller), 13 hopper (nip member), 15 PF roller (second paper feed roller), 51 PF sensor (paper detection means), 73 memory (memory) Means), 82 hopper table, 83 head setting table, 84 continuous drive table, 91 stop determination unit (stop determination unit), 92 secondary control determination unit (next control determination unit), 93 paper feed control execution unit (paper feed control execution) Means), 94 ink ejection control execution section (printing control execution means), P paper.

Claims (5)

A first paper feed roller for transporting paper from the paper feed tray;
A nip member that abuts the first paper feed roller during paper feed and sandwiches the paper in the paper feed tray with the first paper feed roller;
A paper feed control execution means for accelerating the first paper feed roller to a predetermined nip speed, bringing the nip member into contact with the first paper feed roller, and accelerating the first paper feed roller after the contact; ,
Paper detection means disposed on the downstream side in the transport direction of the paper transported from the paper feed tray and detecting the paper after re-acceleration of the first paper feed roller;
The paper feed control execution means terminates the drive control at a predetermined control distance when the paper detection means detects the paper. A second paper feed roller for transporting the paper transported from the paper feed tray by the first paper feed roller to a predetermined paper feed position;
Storage means for storing a table for decelerating and stopping the speed of the first paper feed roller and the second paper feed roller in stages,
2. The paper feed control unit according to claim 1, wherein when the paper detection unit detects the paper, the paper feed control execution unit starts a deceleration control whose speed is managed by the table and ends the drive control. apparatus. A second paper feed roller for transporting the paper transported from the paper feed tray by the first paper feed roller to a predetermined paper feed position;
The hopper table that stops the first paper feed roller and the second paper feed roller after accelerating to the predetermined nip speed, and the first paper feed roller and the second paper feed roller are moved from the predetermined nip speed. A heading table that accelerates to a fast maximum feed speed and then decelerates the speed step by step to a stop and stops the first paper feed roller and the second paper feed roller from the predetermined nip speed to the maximum feed speed. Storage means for storing a continuous drive table that accelerates to
The paper feed control execution means accelerates the first paper feed roller and the second paper feed roller to the predetermined nip speed by the hopper table, accelerates to the maximum feed speed by the continuous drive table, 2. The sheet feeding device according to claim 1, wherein when the sheet detecting means detects the sheet, the deceleration control in which the speed is managed by the heading table is started and the drive control is ended. A sheet feeding device according to any one of claims 1 to 3,
Print control execution means for executing printing on a sheet fed by the sheet feeding device at a predetermined sheet feeding position targeted by the sheet feeding device;
A printer comprising: Stop determination means for determining stop of paper feeding based on detection;
When it is determined that the stop determination unit is stopped, one control execution unit to be executed next is selected from a plurality of control execution units including the paper feed control execution unit and the print control execution unit, Next control determination means for instructing execution of the selected control execution unit,
The printer according to claim 4, further comprising:

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