Media transport device, recording device, recording system, and control method for media transport device

Abstract

The present invention provides a media transport device, a recording device, a recording system, and a control method for a media transport device that can improve the transport performance of the media. [Solution] The media transport device comprises a transport unit that transports the media and a control unit that controls the transport unit. The transport unit has a first transport unit that transports the media and a second transport unit that transports the media downstream of the first transport unit. The control unit selects the transport speed of the media by the second transport unit from a predetermined number of corrected transport speeds based on the difference between the time the media arrives at a predetermined position downstream of the first transport unit and a reference arrival time. Based on the difference and the selected corrected transport speed, the control unit calculates the corrected transport time for transporting the media at the corrected transport speed.

Description

Technical Field

[0001] The present invention relates to a medium transport device, a recording device, a recording system, and a method for controlling a medium transport device.

Background Art

[0002] For example, as disclosed in Patent Document 1, there is disclosed a medium transport device that changes the transport speed of a subsequent medium based on the difference between the arrival time when a preceding medium reaches a predetermined position and a reference arrival time. Thereby, the throughput can be improved for the subsequent medium.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in such a medium transport device, when correcting the transport speed, the calculation of the corrected transport speed becomes complicated. Therefore, there is a risk that the medium cannot be transported smoothly. Accordingly, it is desired to improve the transport performance of the medium.

Means for Solving the Problems

[0005] The medium transport device that solves the above problems includes a transport unit that transports a medium, and a control unit that controls the transport unit. The transport unit has a first transport unit that transports a medium and a second transport unit that transports the medium downstream of the first transport unit. The control unit selects the transport speed of the medium by the second transport unit from a plurality of types of predetermined corrected transport speeds based on the difference between the arrival time of the medium at a predetermined point downstream of the first transport unit and the reference arrival time, and calculates a corrected transport time for transporting the medium at the corrected transport speed based on the difference and the selected corrected transport speed.

[0006] A recording device that solves the above problems comprises a transport unit for transporting a medium, a recording unit for recording on the medium transported by the transport unit, and a control unit for controlling the transport unit and the recording unit. The transport unit comprises a first transport unit for transporting a medium and a second transport unit for transporting the medium downstream of the first transport unit. The control unit selects the transport speed of the medium by the second transport unit from a predetermined number of corrected transport speeds based on the difference between the time the medium arrives at a predetermined point downstream of the first transport unit and a reference arrival time. Based on the difference and the selected corrected transport speed, the control unit calculates a corrected transport time for transporting the medium at the corrected transport speed.

[0007] A recording system that solves the above problems comprises a transport unit for transporting a medium, a recording unit for recording on the medium transported by the transport unit, a post-processing unit for performing post-processing on the medium recorded by the recording unit, and a control unit for controlling the transport unit, the recording unit, and the post-processing unit. The transport unit comprises a first transport unit for transporting a medium and a second transport unit for transporting a medium downstream of the first transport unit. The control unit selects a transport speed for the medium by the second transport unit from a predetermined number of corrected transport speeds based on the difference between the time the medium arrives at a predetermined point downstream of the first transport unit and a reference arrival time. Based on the difference and the selected corrected transport speed, the control unit calculates a corrected transport time for transporting the medium at the corrected transport speed.

[0008] A control method for a media transport device that solves the above problems is a control method for a media transport device comprising a first transport unit that transports a medium and a second transport unit that transports the medium downstream of the first transport unit, the method comprising: selecting the transport speed of the medium by the second transport unit from a predetermined number of corrected transport speeds based on the difference between the time the medium arrives at a predetermined point downstream of the first transport unit and a reference arrival time; and calculating a corrected transport time for transporting the medium at the corrected transport speed based on the difference and the selected corrected transport speed. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a schematic diagram showing a recording device according to the first embodiment. [Figure 2] Figure 2 is a schematic diagram showing the control contents of the second drive unit of the first embodiment. [Figure 3] Figure 3 is a schematic diagram showing the control contents of the second drive unit of the first embodiment. [Figure 4] Figure 4 is a schematic diagram showing the control contents of the second drive unit of the first embodiment. [Figure 5] Figure 5 is a schematic diagram showing the control contents of the second drive unit of the first embodiment. [Figure 6] Figure 6 is a schematic diagram showing the relationship between the difference between the arrival time and the reference arrival time and the corrected transport speed in the first embodiment. [Figure 7] Figure 7 is a flowchart showing the transport data control process of the first embodiment. [Figure 8] Figure 8 is a schematic diagram showing the recording system of the second embodiment. [Figure 9] Figure 9 is a schematic diagram showing a recording device according to the third embodiment. [Figure 10] Figure 10 is a schematic diagram showing the control contents of the second drive unit of the third embodiment. [Figure 11] Figure 11 is a schematic diagram showing the control contents of the first drive unit of the third embodiment. [Modes for carrying out the invention]

[0010] [First Embodiment] Hereinafter, an embodiment of a recording device equipped with a media transport device and a control method for the media transport device will be described with reference to the drawings. From this point forward, the recording device will be described as being placed on a horizontal plane.

[0011] <Configuration of recording device 11> As shown in FIG. 1, the recording device 11 is configured to record an image on the medium 99. The recording device 11 may be, for example, an inkjet printer that records an image by ejecting ink, which is an example of a liquid, onto the medium 99.

[0012] The recording device 11 may include a medium storage unit 12. The recording device 11 may include a plurality of medium storage units 12. The medium storage unit 12 can store the medium 99. The medium storage unit 12 can store a plurality of media 99 in a stacked state. The medium storage unit 12 may be a tray on which one or more media 99 can be placed.

[0013] The recording device 11 includes a medium conveyance device 13. The medium conveyance device 13 is configured to convey the medium 99 for recording an image. The medium conveyance device 13 includes a conveyance unit 14. The conveyance unit 14 is configured to convey the medium 99. The conveyance unit 14 conveys the medium 99 in the conveyance direction D along the conveyance path 15. The conveyance path 15 is the path along which the medium 99 is conveyed. The conveyance direction D is the direction in which the medium 99 is conveyed. In the drawing, the conveyance path 15 is indicated by a dashed line. In the present embodiment, upstream means upstream in the conveyance direction D, and downstream means downstream in the conveyance direction D.

[0014] The recording device 11 includes a recording unit 16. The recording unit 16 is configured to record an image on the medium 99. The recording unit 16 is configured to record on the medium 99 conveyed by the conveyance unit 14. The recording unit 16 may record on the medium 99 by ejecting a liquid onto the medium 99. The recording unit 16 is provided at a position along the conveyance path 15.

[0015] The recording unit 16 is of the line head type, but may also be of the serial head type. The line head type is a method in which a head extending in the crossing direction crossing the conveyance direction D can eject liquid all at once over the entire crossing direction of the medium 99. The serial head is a method in which the head can eject liquid onto the medium 99 while moving in the crossing direction.

[0016] The recording device 11 includes a control unit 17. The control unit 17 comprehensively controls the recording device 11. The control unit 17 controls various operations executed in the recording device 11. The control unit 17 controls the conveyance unit 14 and the recording unit 16.

[0017] The control unit 17 can be configured as a circuit including: α: one or more processors that execute various processes according to a computer program, β: one or more dedicated hardware circuits that execute at least some of the various processes, or γ: a combination thereof. The hardware circuit is, for example, an application-specific integrated circuit. The processor includes a CPU and memories such as a RAM and a ROM, and the memories store program codes or instructions configured to cause the CPU to execute processes. The memory, that is, the computer-readable medium, includes any readable medium accessible by a general-purpose or dedicated computer.

[0018] The medium conveyance device 13 may include a control unit 17. The control unit 17 may comprehensively control the medium conveyance device 13 instead of the recording device 11. The control unit 17 may control various operations executed in the medium conveyance device 13. s

[0019] The conveyance unit 14 includes a first conveyance unit 21 and a second conveyance unit 22. That is, the recording device 11 and the medium conveyance device 13 include the first conveyance unit 21 and the second conveyance unit 22. The conveyance unit 14 may further include a third conveyance unit 23 and a discharge conveyance unit 24. That is, the recording device 11 and the medium conveyance device 13 may further include the third conveyance unit 23 and the discharge conveyance unit 24.

[0020] The first conveyance unit 21, the second conveyance unit 22, the third conveyance unit 23, and the discharge conveyance unit 24 are provided at positions along the conveyance path 15. The first conveyance unit 21, the second conveyance unit 22, the third conveyance unit 23, and the discharge conveyance unit 24 are arranged in order from upstream to downstream along the conveyance path 15.

[0021] The first transport unit 21 is located upstream of the recording unit 16. The second transport unit 22 is located upstream of the recording unit 16. The third transport unit 23 is located both upstream of the recording unit 16 and opposite to the recording unit 16. In other words, the recording unit 16 records onto the medium 99 transported by the third transport unit 23. The discharge transport unit 24 is located downstream of the recording unit 16.

[0022] The first transport unit 21 is located at the uppermost part of the transport path 15. The first transport unit 21 is configured to transport the medium 99. The first transport unit 21 is configured to transport the topmost medium 99 among the medium 99 stored in the medium storage unit 12. The first transport unit 21 is a supply unit that feeds the medium 99 stored in the medium storage unit 12. The first transport unit 21 is configured to transport the medium 99 from the medium storage unit 12 to the second transport unit 22.

[0023] The first transport unit 21 comprises a feed roller 30 and a first transport drive unit 31. The feed roller 30 feeds the medium 99 by rotating. The feed roller 30 is positioned to contact the topmost sheet of medium 99 loaded in the medium storage unit 12. The feed roller 30 feeds the medium 99 one sheet at a time from the medium storage unit 12.

[0024] The first transport drive unit 31 is connected to the feed roller 30. The first transport drive unit 31 is a drive source that rotates the feed roller 30. The first transport drive unit 31 may be a motor. The first transport drive unit 31 rotates the feed roller 30 by being driven based on a drive signal from the control unit 17.

[0025] The second transport unit 22 is located downstream of the first transport unit 21. The second transport unit 22 is configured to transport the medium 99. The second transport unit 22 is configured to transport the medium 99 from the first transport unit 21 to the third transport unit 23.

[0026] The second conveying unit 22 comprises a first roller pair 32, a second roller pair 33, and a second conveying drive unit 34. The second roller pair 33 is located downstream of the first roller pair 32. The first roller pair 32 and the second roller pair 33 convey the medium 99 by rotating.

[0027] The second transport drive unit 34 is connected to the first roller pair 32. The second transport drive unit 34 is connected to the second roller pair 33. The second transport drive unit 34 is a drive source that rotates the first roller pair 32 and the second roller pair 33. The second transport drive unit 34 may be a motor. The second transport drive unit 34 rotates the first roller pair 32 and the second roller pair 33 by being driven based on a drive signal from the control unit 17.

[0028] The third transport unit 23 is located downstream of the second transport unit 22. The third transport unit 23 is configured to transport the medium 99. The third transport unit 23 is configured to transport the medium 99 from the second transport unit 22 to the discharge transport unit 24.

[0029] The third transport unit 23 comprises a pair of register rollers 35 and a third transport drive unit 36. In other words, the recording device 11 and the media transport device 13 each comprise a pair of register rollers 35 and a third transport drive unit 36.

[0030] The resist roller pair 35 is located downstream of the second conveying section 22. The resist roller pair 35 is abutted against by the medium 99 being conveyed by the second conveying section 22. The resist roller pair 35 is configured to correct the skew of the medium 99. The resist roller pair 35 conveys the medium 99 by rotating.

[0031] The third transport drive unit 36 ​​is connected to the register roller pair 35. The third transport drive unit 36 ​​is a drive source that rotates the register roller pair 35. The third transport drive unit 36 ​​may be a motor. The third transport drive unit 36 ​​rotates the register roller pair 35 by being driven based on a drive signal from the control unit 17.

[0032] The third transport unit 23 includes a media support unit 37. The media support unit 37 is positioned along the transport path 15. The media support unit 37 is configured to transport the media 99 while supporting it. The media support unit 37 is positioned opposite the recording unit 16 across the transport path 15.

[0033] The media support unit 37 may include an endless conveyor belt 38 and a pair of pulleys 39. The conveyor belt 38 is stretched over the pair of pulleys 39. The conveyor belt 38 faces the recording unit 16 across the conveyor path 15. The conveyor belt 38 supports a portion of the media 99 in a flat state. The conveyor belt 38 conveys the media 99 along the conveyor path 15 by rotating while holding the media 99 in its grip. One of the pulleys 39 rotates due to a driving force from a belt drive unit (not shown). As a result, the conveyor belt 38 conveys the media 99 along the conveyor path 15.

[0034] The media support unit 37 is rotatable about one pulley 39. By rotating about one pulley 39, the media support unit 37 is provided to move between a support position shown by a solid line and a retracted position shown by a dashed line. The support position is the position where the media 99 is supported and faces the recording unit 16. The retracted position is the position away from the recording unit 16. When the media support unit 37 moves to the retracted position, maintenance of the recording unit 16 is performed by a maintenance device (not shown).

[0035] The discharge and transport unit 24 is located downstream of the third transport unit 23. The discharge and transport unit 24 is configured to transport the medium 99. The discharge and transport unit 24 is configured to transport the medium 99 from the third transport unit 23 to the outside of the recording device 11.

[0036] The discharge conveying unit 24 includes a pair of discharge rollers 40. The pair of discharge rollers 40 conveys the medium 99 by rotating. The pair of discharge rollers 40 rotates due to a driving force from a discharge drive unit (not shown). The discharge drive unit may be a motor.

[0037] The media transport device 13 includes a first media detection unit 41 and a second media detection unit 42. In other words, the recording device 11 includes a first media detection unit 41 and a second media detection unit 42. The first media detection unit 41 and the second media detection unit 42 may be physical sensors or optical sensors.

[0038] The first medium detection unit 41 is located along the transport path 15. The first medium detection unit 41 is located downstream of the first transport unit 21. The first medium detection unit 41 is located downstream of the first roller pair 32. The first medium detection unit 41 is located upstream of the second roller pair 33. In other words, the first medium detection unit 41 is located along the transport path 15 between the first roller pair 32 and the second roller pair 33.

[0039] The first media detection unit 41 is configured to detect the medium 99 being transported along the transport path 15. In particular, the first media detection unit 41 is configured to detect the leading edge of the medium 99. That is, the first media detection unit 41 detects that the medium 99 is being transported by the second transport unit 22. Hereafter, the position in which the first media detection unit 41 can detect the medium 99 is indicated as a predetermined position. The predetermined position can be said to be a position downstream of the first transport unit 21. The timing at which the first media detection unit 41 detects the leading edge of the medium 99 is indicated as the first detection timing.

[0040] The second medium detection unit 42 is located along the transport path 15. The second medium detection unit 42 is located downstream of the second transport unit 22. The second medium detection unit 42 is located upstream of the resist roller pair 35. The second medium detection unit 42 may be located a short distance upstream of the resist roller pair 35.

[0041] The second media detection unit 42 is configured to detect the medium 99 being transported along the transport path 15. In particular, the second media detection unit 42 is configured to detect the leading edge of the medium 99. The second media detection unit 42 may also be configured to detect the leading edge of the medium 99 as it abuts against the resist roller pair 35. Hereafter, the position in which the second media detection unit 42 can detect the medium 99 is indicated as the detection position. The timing at which the second media detection unit 42 detects the leading edge of the medium 99 is indicated as the second detection timing.

[0042] <Control details of the second transport unit 22> Now, with reference to Figures 2 to 6, the control details of the second transport unit 22 will be explained. As shown in Figure 2, the transport speed by the second transport unit 22 is controlled for each medium 99 transported along the transport path 15. The transport speed by the second transport unit 22 is controlled for each control period during which the medium 99 is transported.

[0043] The control period includes a first acceleration period T1, a normal transport period T2, a second acceleration period T3, a corrective transport period T4, a first deceleration period T5, a sudden transport period T6, and a second deceleration period T7. The first acceleration period T1 is the period during which the transport speed by the second transport unit 22 is accelerated from 0 to the normal transport speed v0. The normal transport period T2 is the period during which the medium 99 is transported at the normal transport speed v0.

[0044] The normal transport speed v0 is the transport speed when receiving the medium 99 from the first transport unit 21. The normal transport speed v0 is a speed equal to or greater than the transport speed at which the medium 99 is transported by the first transport unit 21. The normal transport speed v0 is equal to the transport speed at which the medium 99 is transported by the third transport unit 23. In particular, the normal transport speed v0 is equal to the transport speed at which the medium 99 is transported by the medium support unit 37. In other words, the normal transport speed v0 is equal to the transport speed at which recording is performed on the medium 99. Thus, the normal transport speed v0 can be said to be the standard transport speed in the recording device 11 and the medium transport device 13.

[0045] The second acceleration period T3 is the period during which the transport speed by the second transport unit 22 is accelerated to the corrected transport speed. The corrected transport period T4 is the period during which the medium 99 is transported at the corrected transport speed. In Figure 2, the corrected transport speed is the reference speed v1.

[0046] The corrected transport speed is faster than the normal transport speed v0. This allows for an improvement in the transport speed by the second transport unit 22. In this way, the throughput for transporting the medium 99 can be improved.

[0047] The corrected transport speed includes multiple speeds. One of these speeds is selected for the corrected transport speed. The corrected transport speed includes the reference speed v1 shown in Figures 2 and 3, the high speed v2 shown in Figure 4, and the low speed v3 shown in Figure 5. The reference speed v1 is the speed that serves as the basis for the corrected transport speed. The reference speed v1 is a speed based on the reference arrival time, which will be described later. The high speed v2 is faster than the reference speed v1. The low speed v3 is slower than the reference speed v1. The low speed v3 is equal to the sudden transport speed v3, which will be described later.

[0048] Thus, the reference speed v1, high speed v2, and low speed v3 are faster than the normal transport speed v0. In other words, the reference speed v1, high speed v2, and low speed v3 are faster than the transport speed by the first transport unit 21. To put it another way, the normal transport speed v0 is slower than the corrected transport speed. The normal transport speed v0 is slower than the low speed v3 and the abrupt transport speed v3.

[0049] The first deceleration period T5 is the period during which the transport speed by the second transport unit 22 is reduced from the corrected transport speed to the sudden transport speed v3. The sudden transport period T6 is the period during which the medium 99 is transported at the sudden transport speed v3. The second deceleration period T7 is the period during which the transport speed by the second transport unit 22 is reduced from the sudden transport speed v3 to 0.

[0050] The abutment transport speed v3 is the transport speed at which the second transport unit 22 abuts the medium 99 against the resist roller pair 35. The abutment transport speed v3 is slower than the reference speed v1 and the high speed v2. The abutment transport speed v3 is equal to the low speed v3.

[0051] The second deceleration period T7 includes the timing when the resist roller pair 35 begins to re-transport the medium 99 that has come into contact with the resist roller pair 35. The resist roller pair 35 transports the medium 99 at the normal transport speed v0.

[0052] With the rotation of the resist roller pair 35 stopped, the second transport unit 22 abuts the medium 99 against the resist roller pair 35 at abutment transport speed v3, causing the medium 99 to deflect. During the second deceleration period T7, the transport speed by the second transport unit 22 is reduced from the abutment transport speed v3 to 0, thereby eliminating the deflection in the medium 99. Figures 2 to 5 omit the illustration of the timing after T19, but the transport speed by the second transport unit 22 is accelerated from 0 to the normal transport speed v0 before the deflection in the medium 99 is completely eliminated. By accelerating the transport speed by the second transport unit 22 from 0 to the normal transport speed v0 before the deflection in the medium 99 is completely eliminated, the second transport unit 22 can be prevented from becoming a transport load. Furthermore, when transporting multiple media 99 in succession, the period during which the transport speed by the second transport unit 22 is accelerated from 0 to the normal transport speed v0 before the deflection in the media 99 is completely eliminated corresponds to the first acceleration period T1 for the subsequent media 99.

[0053] As shown in Figures 2 to 5, the first medium detection unit 41 controls the corrected transport speed and corrected transport time based on the arrival time of the medium 99 to reach a predetermined position. The arrival time is the time from when the transport of the medium 99 starts until the medium 99 reaches the predetermined position. In other words, the arrival time is the time from when the first transport unit 21 starts transporting the medium 99 until the medium 99 reaches the predetermined position. The corrected transport time is the time for transporting the medium 99 at the corrected transport speed.

[0054] The memory stores a predefined reference arrival time. The reference arrival time is the time that serves as the basis for determining the arrival time. The reference arrival time is normally defined in the transport period T2. Specifically, the reference arrival time is the timing indicated by code T12 in Figures 2 to 5.

[0055] The corrected transport speed and corrected transport time are controlled based on the difference between the arrival time and the reference arrival time. Specifically, the difference between the arrival time and the reference arrival time is the second difference Δt2 shown in Figure 3, the third difference Δt3 shown in Figure 4, and the fourth difference Δt4 shown in Figure 5. In Figure 2, the difference between the arrival time and the reference arrival time is 0. Hereafter, the difference between the arrival time and the reference arrival time will simply be referred to as the difference.

[0056] The difference is the value obtained by subtracting the reference arrival time from the arrival time. The difference is a positive value if the arrival time is longer than the reference arrival time. The difference is a negative value if the arrival time is shorter than the reference arrival time. Therefore, the second difference Δt2 shown in Figure 3 and the third difference Δt3 shown in Figure 4 are positive values. The fourth difference Δt4 shown in Figure 5 is a negative value.

[0057] As shown in Figure 6, the difference is assigned to a difference range. The difference range may include multiple ranges. The difference range may include a first range, a second range, and a third range. The first range is the range where the difference is less than the first threshold and greater than the second threshold. The second range is the range where the difference is greater than or equal to the first threshold. The third range is the range where the difference is less than or equal to the second threshold. The first threshold is greater than the second threshold. The first threshold may be a positive number, and the second threshold may be a negative number.

[0058] If the difference falls within the first range, the reference speed v1 is selected as the corrected transport speed. If the difference falls within the second range, the high speed v2 is selected as the corrected transport speed. If the difference falls within the third range, the low speed v3 is selected as the corrected transport speed.

[0059] The corrected transport time is controlled to minimize the difference so that the medium 99 can be transported to the third transport unit 23 at an appropriate timing. Preferably, the corrected transport time is controlled to eliminate the difference so that the medium 99 can be transported to the third transport unit 23 at an appropriate timing. In particular, the corrected transport time is controlled so that the leading edge of the medium 99 is detected by the second medium detection unit 42 at a predetermined second detection timing based on the difference. The second detection timing is the timing indicated by the symbol T17 in Figures 2 to 5.

[0060] As shown in Figures 2 to 5, in this embodiment, during the first acceleration period T1 and the second deceleration period T7, the transport speed of the medium 99 by the second transport unit 22 is controlled in the same way regardless of the difference. In this embodiment, at the timing indicated by reference numeral T17, regardless of the difference, the transport speed of the medium 99 by the second transport unit 22 is controlled in the same way so that the leading edge of the medium 99 is detected at the detection position by the second medium detection unit 42.

[0061] <Transport Data Control Processing> Next, the transport data control process will be explained with reference to Figure 7. The transport data control process is executed by the control unit 17 at predetermined intervals.

[0062] As shown in Figure 7, in step S10, the control unit 17 determines whether or not the leading edge of the medium 99 has been detected at a predetermined position based on the detection signal from the first medium detection unit 41. If the control unit 17 determines that the leading edge of the medium 99 has not been detected at the predetermined position, it terminates the transport data control process. If the control unit 17 determines that the leading edge of the medium 99 has been detected at the predetermined position, it proceeds to step S11.

[0063] In step S11, the control unit 17 performs a time arrival calculation process. In this process, the control unit 17 calculates the time elapsed since the start of transport of the medium 99 as the time arrival. This allows the control unit 17 to calculate the time it takes for the medium 99 to reach a predetermined position from the start of transport of the medium 99. The control unit 17 stores the time arrival in memory.

[0064] In step S12, the control unit 17 performs a difference calculation process. In this process, the control unit 17 reads the reference arrival time that is pre-stored in memory. The control unit 17 calculates the difference between the calculated arrival time and the reference arrival time. This allows the control unit 17 to calculate the difference between the arrival time of the medium 99 to a predetermined position and the reference arrival time. The control unit 17 stores the difference in memory.

[0065] In step S13, the control unit 17 performs a difference determination process. In this process, the control unit 17 refers to the difference range pre-stored in memory and identifies the difference range that includes the difference calculated in step S12.

[0066] More specifically, the control unit 17 determines that the difference falls within the first range if the difference is less than the first threshold and greater than the second threshold. The control unit 17 determines that the difference falls within the second range if the difference is greater than or equal to the first threshold. The control unit 17 determines that the difference falls within the third range if the difference is less than or equal to the second threshold.

[0067] In step S14, the control unit 17 performs a correction transport speed selection process. In this process, the control unit 17 selects a correction transport speed from a plurality of types of correction transport speeds that corresponds to the difference range that includes the difference.

[0068] More specifically, if the difference falls within the first range, the control unit 17 selects a reference speed v1 from several types of corrected transport speeds. If the difference falls within the second range, the control unit 17 selects a high speed v2 from several types of corrected transport speeds. If the difference falls within the third range, the control unit 17 selects a low speed v3 from several types of corrected transport speeds.

[0069] In this way, the control unit 17 selects the transport speed of the medium 99 by the second transport unit 22 from a predetermined number of corrected transport speeds based on the difference between the time the medium 99 arrives at a predetermined position and the reference arrival time.

[0070] In step S15, the control unit 17 performs a transport time calculation process. In this process, the control unit 17 calculates a corrected transport time based on the difference calculated in step S12 and the corrected transport speed selected in step S14, so that the second detection timing by the second medium detection unit 42 becomes a predetermined time.

[0071] In more detail, the control unit 17 calculates the adjustment target time based on the difference calculated in step S12. The adjustment target time is the time from the actual time to reach the predetermined position to the time to reach the detection position.

[0072] The control unit 17 calculates the normal transport time, the corrected transport time, and the sudden transport time based on the difference calculated in step S12, the corrected transport speed selected in step S14, and the calculated adjustment target time. The normal transport time is the transport time for transporting the medium 99 at the normal transport speed v0. The sudden transport time is the transport time for transporting the medium 99 at the sudden transport speed v3.

[0073] In particular, if the corrected transport speed is not the low speed v3, the control unit 17 calculates the normal transport time, the corrected transport time, and the sudden transport time based on the second acceleration period T3 and the first deceleration period T5.

[0074] The control unit 17 calculates the normal transport time, the corrected transport time, and the sudden transport time so that the medium 99 is transported from a predetermined position to the detection position from the actual arrival time to a predetermined second detection timing. The control unit 17 calculates the normal transport time, the corrected transport time, and the sudden transport time so that the sum of the normal transport time, the corrected transport time, the sudden transport time, the time of the second acceleration period T3, and the time of the first deceleration period T5 becomes the adjustment target time.

[0075] For the second acceleration period T3, the time corresponding to the speed before acceleration and the speed after acceleration is stored in memory. For the first deceleration period T5, the time corresponding to the speed before deceleration and the speed after deceleration is stored in memory. For the distance the medium 99 is transported during the second acceleration period T3, the distance corresponding to the speed before acceleration and the speed after acceleration is stored in memory. For the distance the medium 99 is transported during the first deceleration period T5, the distance corresponding to the speed before deceleration and the speed after deceleration is stored in memory.

[0076] When the corrected transport speed is low speed v3, the control unit 17 calculates the normal transport time, the corrected transport time, and the sudden transport time based on the second acceleration period T3. In this case, the corrected transport time is the transport time at the sudden transport speed v3.

[0077] The control unit 17 calculates the normal transport time and the sudden transport time so as to transport the medium 99 from a predetermined position to a detection position from the actual arrival time to a predetermined second detection timing. The sudden transport time includes the correction transport time. The control unit 17 calculates the normal transport time and the sudden transport time so as to the sum of the normal transport time, the sudden transport time and the time of the second acceleration period T3, the total time to be adjusted.

[0078] The duration of the second acceleration period T3 is stored in memory as the time corresponding to the speed before acceleration and the speed after acceleration. The distance over which the medium 99 is transported during the second acceleration period T3 is stored in memory as the distance corresponding to the speed before acceleration and the speed after acceleration.

[0079] The control unit 17 calculates the normal transport period T2, the second acceleration period T3, the correction transport period T4, the first deceleration period T5, and the sudden transport period T6 based on the calculated normal transport time, the corrected transport time, and the sudden transport time. In particular, when the corrected transport speed is low speed v3, the control unit 17 calculates the normal transport period T2, the second acceleration period T3, and the sudden transport period T6 based on the calculated normal transport time and the sudden transport time.

[0080] The control unit 17 may determine the normal transport time, corrected transport time, and sudden transport time based on the lower limit of the normal transport time. The lower limit of the normal transport time is defined so that the medium 99 is transported at the normal transport speed v0 continuously from the start of the normal transport period T2 until after the reference arrival time. The lower limit of the normal transport time may be greater than or equal to the time until the transport of the preceding medium 99 by the second transport unit 22 is completed. This allows the control unit 17 to have the preceding medium 99 and the succeeding medium 99 transported by the second transport unit 22 at the normal transport speed v0 until the transport of the preceding medium 99 by the second transport unit 22 is completed.

[0081] In step S16, the control unit 17 performs a correction transport data setting process. In this process, the control unit 17 generates correction transport data for transporting the medium 99 to the second transport unit 22 based on the correction transport speed selected in step S14 and the various transport times and periods determined in step S15. The control unit 17 sets the generated correction transport data into memory.

[0082] <Transport control processing> Next, the transport control process will be described. The transport control process is executed by the control unit 17 when the transport of the medium 99 begins.

[0083] In this process, when the transport of the medium 99 begins, the control unit 17 controls the first transport unit 21 to supply the medium 99 from the medium storage unit 12. When the transport of the medium 99 begins, the control unit 17 controls the second transport unit 22 based on the transport data stored in memory. When the transport of the medium 99 begins, the control unit 17 starts counting to calculate the arrival time.

[0084] The transport data includes normal transport data and corrected transport data. Normal transport data is transport data in which the medium 99 is not transported at the corrected transport speed. Normal transport data may also be transport data in which the medium 99 is transported at the normal transport speed v0, and then transported at the sudden transport speed v3. Normal transport data may also include a first acceleration period T1, a normal transport period T2, a second acceleration period T3, a sudden transport period T6, and a second deceleration period T7.

[0085] When the transport of the medium 99 begins, the control unit 17 controls the second transport unit 22 based on the normal transport data. The control unit 17 executes transport data control processing and sets the corrected transport data in memory, and then transports the medium 99 based on the corrected transport data, not the normal transport data.

[0086] As a result, the control unit 17 changes the transport speed by the second transport unit 22 for each medium 99 transported along the transport path 15 in the order of normal transport speed v0, corrected transport speed, and sudden transport speed v3. In particular, if the corrected transport speed is low speed v3 based on the corrected transport data, the control unit 17 changes the transport speed by the second transport unit 22 in the order of normal transport speed v0 and sudden transport speed v3, since low speed v3 and sudden transport speed v3 are equal.

[0087] Thus, the control unit 17 controls the second transport unit 22 to transport the medium 99 at a normal transport speed v0 during the normal transport period T2, which is not the corrected transport period T4. The control unit 17 controls the second transport unit 22 to transport the medium 99 at a corrected transport speed during the corrected transport period T4, which is based on the corrected transport time. The control unit 17 controls the second transport unit 22 to transport the medium 99 at a sudden transport speed v3 during the sudden transport period T6.

[0088] In particular, when multiple media 99, including a preceding medium 99 and a succeeding medium 99, are transported along the transport path 15, the normal transport period T2 includes the period in which the trailing end of the preceding medium 99 is transported by the second transport unit 22 and the transport of the succeeding medium 99 has begun. Thus, during the normal transport period T2, the second transport unit 22 transports both the preceding medium 99 and the succeeding medium 99.

[0089] During the normal transport period T2, the transport of the preceding medium 99 by the second transport unit 22 is completed. In other words, before the corrected transport period T4, the transport of the preceding medium 99 by the second transport unit 22 is completed. Thus, during the corrected transport period T4, the second transport unit 22 has completed the transport of the preceding medium 99 and will transport the subsequent medium 99.

[0090] As a result, the control unit 17 controls the second transport unit 22 to transport the preceding medium 99 and the succeeding medium 99 at the normal transport speed v0 while the trailing end of the preceding medium 99 is being transported by the second transport unit 22. After the transport of the preceding medium 99 by the second transport unit 22 is completed, the control unit 17 controls the second transport unit 22 to transport the succeeding medium 99 at the corrected transport speed.

[0091] When the control unit 17 changes the transport speed of the second transport unit 22, it controls the second transport unit 22 to perform curved acceleration and deceleration. In other words, the control unit 17 performs curved driving, which is a curved acceleration and deceleration, rather than trapezoidal driving or triangular driving, which are linear acceleration and deceleration. Curved driving is achieved by changing the rate of change of acceleration and deceleration, rather than by keeping the rate of change constant.

[0092] In such cases, the control unit 17 reads an acceleration transport pattern from memory and controls the second transport unit 22 to perform a curved acceleration. The control unit 17 reads a deceleration transport pattern from memory and controls the second transport unit 22 to perform a curved deceleration.

[0093] The accelerated transport pattern includes a transport pattern for accelerating the transport speed by the second transport unit 22 from 0 to the normal transport speed v0. The accelerated transport pattern includes a transport pattern for accelerating the transport speed by the second transport unit 22 from the normal transport speed v0 to the reference speed v1. The accelerated transport pattern includes a transport pattern for accelerating the transport speed by the second transport unit 22 from the normal transport speed v0 to the high speed v2. The accelerated transport pattern includes a transport pattern for accelerating the transport speed by the second transport unit 22 from the normal transport speed v0 to the low speed v3.

[0094] The deceleration transport pattern includes a transport pattern for reducing the transport speed by the second transport unit 22 from a reference speed v1 to an abrupt transport speed v3. The deceleration transport pattern includes a transport pattern for reducing the transport speed by the second transport unit 22 from a high speed v2 to an abrupt transport speed v3. The deceleration transport pattern includes a transport pattern for reducing the transport speed by the second transport unit 22 from an abrupt transport speed v3 to 0.

[0095] In this way, by controlling the system to select one of several types of corrected transport speeds, the number of acceleration / deceleration transport patterns can also be reduced. This helps to suppress the increase in memory capacity.

[0096] <Specific example of control content of the second transport unit 22> Next, we will explain a specific example of the control content of the second transport unit 22 with reference to Figures 2 to 5. As shown in Figure 2, when the transport of the medium 99 begins at the timing indicated by symbol T10, the first acceleration period T1 begins, and the transport speed by the second transport unit 22 accelerates from 0 to the normal transport speed v0. In this case, a curved acceleration occurs. At the timing indicated by symbol T11, the normal transport period T2 begins, and the transport speed by the second transport unit 22 is maintained at the normal transport speed v0.

[0097] When the leading edge of the medium 99 is detected by the first medium detection unit 41 at the timing indicated by symbol T12, the arrival time from the start of medium 99 transport becomes the reference arrival time. At this time, the difference becomes 0. As a result, the reference speed v1 is selected from multiple corrected transport speeds, and thereafter, the first time t1 is determined as the corrected transport time. Based on the corrected transport time, the start timing of the second acceleration period T3, the start timing of the corrected transport period T4, and the start timing of the first deceleration period T5 are determined.

[0098] At the timing indicated by symbol T13, the second acceleration period T3 begins, and the transport speed by the second transport unit 22 accelerates from the normal transport speed v0 to the reference speed v1. In this case, a curved acceleration occurs. At the timing indicated by symbol T14, the correction transport period T4 begins, and the transport speed by the second transport unit 22 is maintained at the reference speed v1.

[0099] At the timing indicated by symbol T15, the first time t1 has elapsed since the timing indicated by symbol T14, and the first deceleration period T5 begins. The transport speed by the second transport unit 22 is reduced from the reference speed v1 to the abrupt transport speed v3. In this case, a curved deceleration occurs. At the timing indicated by symbol T16, the abrupt transport period T6 begins, and the transport speed by the second transport unit 22 is maintained at the abrupt transport speed v3. As a result, at a certain timing indicated by symbol T17, the leading edge of the medium 99 is detected by the second medium detection unit 42.

[0100] At the timing indicated by symbol T18, the second deceleration period T7 begins, and the transport speed by the second transport unit 22 is reduced from the initial transport speed v3 to 0. In this case, a curved deceleration occurs. At the timing indicated by symbol T19, the transport speed by the second transport unit 22 becomes 0.

[0101] As shown in Figure 3, after the reference arrival time is reached, the leading edge of the medium 99 may be detected by the first medium detection unit 41 at the timing indicated by symbol T22. In this case, the difference becomes the second difference Δt2. The second difference Δt2 is included in the first range. As a result, after the reference speed v1 is selected from multiple corrected transport speeds, the second time t2 is determined as the corrected transport time. The second time t2 is longer than the first time t1.

[0102] At the timing indicated by symbol T23, the second acceleration period T3 begins, and the transport speed by the second transport unit 22 accelerates from the normal transport speed v0 to the reference speed v1. In this case, a curved acceleration occurs. At the timing indicated by symbol T24, the correction transport period T4 begins, and the transport speed by the second transport unit 22 is maintained at the reference speed v1.

[0103] At the timing indicated by symbol T15, the second time t2 has elapsed since the timing indicated by symbol T24, and the first deceleration period T5 begins, at which point the transport speed by the second transport unit 22 is reduced from the reference speed v1 to the target transport speed v3. In this case as well, at a certain timing indicated by symbol T17, the leading edge of the medium 99 is detected by the second medium detection unit 42.

[0104] As shown in Figure 4, after the reference arrival time is reached, the leading edge of the medium 99 may be detected by the first medium detection unit 41 at the timing indicated by symbol T32. In this case, the difference becomes the third difference Δt3. The third difference Δt3 is included in the second range. As a result, after the high speed v2 is selected from multiple corrected transport speeds, the third time t3 is determined as the corrected transport time.

[0105] At the timing indicated by symbol T33, the second acceleration period T3 begins, and the transport speed by the second transport unit 22 accelerates from the normal transport speed v0 to the high speed v2. In this case, a curved acceleration occurs. At the timing indicated by symbol T34, the correction transport period T4 begins, and the transport speed by the second transport unit 22 is maintained at the high speed v2.

[0106] At the timing indicated by symbol T35, the third time t3 has elapsed since the timing indicated by symbol T34, and the first deceleration period T5 begins. The transport speed by the second transport unit 22 is reduced from high speed v2 to abutment transport speed v3. In this case, a curved deceleration occurs. At the timing indicated by symbol T36, the abutment transport period T6 begins, and the transport speed by the second transport unit 22 is maintained at abutment transport speed v3. Even in this case, the leading edge of the medium 99 is detected by the second medium detection unit 42 at a certain timing indicated by symbol T17.

[0107] As shown in Figure 5, before the reference arrival time is reached, the leading edge of the medium 99 may be detected by the first medium detection unit 41 at the timing indicated by symbol T42. In this case, the difference becomes the fourth difference Δt4. The fourth difference Δt4 is included in the third range. As a result, after a low speed v3 is selected from multiple corrected transport speeds, the fourth time t4 is determined as the sum of the corrected transport time and the sudden transport time. The sudden transport time is the time during which the medium 99 is transported at the sudden transport speed v3.

[0108] At the timing indicated by symbol T43, the second acceleration period T3 begins, and the transport speed by the second transport unit 22 accelerates from the normal transport speed v0 to a low speed v3. In other words, it accelerates from the normal transport speed v0 to the sudden transport speed v3. In this case, a curved acceleration occurs. At the timing indicated by symbol T44, the sudden transport period T6 begins, and the transport speed by the second transport unit 22 is maintained at the sudden transport speed v3. The sudden transport period T6 includes the correction transport period T4. In this case as well, at a certain timing indicated by symbol T17, the leading edge of the medium 99 is detected by the second medium detection unit 42.

[0109] <Operation and Effects of the First Embodiment> The operation and effects of the first embodiment will now be described. (1-1) The control unit 17 selects the transport speed of the medium 99 by the second transport unit 22 from a predetermined set of correction transport speeds based on the difference between the time the medium 99 arrives at a predetermined position and the reference arrival time. Based on the difference and the selected correction transport speed, the control unit 17 calculates the correction transport time for transporting the medium 99 at the correction transport speed. With this configuration, acceleration and deceleration corresponding to the selected correction transport speed can be performed smoothly, and by adjusting the correction transport speed, the medium 99 can be transported at an appropriate timing. In particular, even if there is a bias in the transport time of the medium 99 by the first transport unit 21, the medium 99 can be transported at an appropriate timing, and the timing of the supply and delivery of the medium 99 by the first transport unit 21 can be made flexible. For this reason, when correcting the transport speed, the complexity of calculating the correction transport speed can be suppressed. Consequently, the transport performance of the medium 99 can be improved. By improving the transport performance of the medium 99 in this way, recording can be performed on the medium 99 at an appropriate timing.

[0110] In addition, the medium 99 that has reached a predetermined position can be transported at a corrected transport speed based on the difference. Therefore, the transport performance of the medium 99 can be improved.

[0111] (1-2) The corrected transport speed includes a reference speed v1 based on the reference arrival time, a high speed v2 that is faster than the reference speed v1, and a low speed v3 that is slower than the reference speed v1. With this configuration, the corrected transport speed can be controlled not only to a reference speed v1 based on the reference arrival time, but also to a high speed v2 that is faster than the reference speed v1 and a low speed v3 that is slower than the reference speed v1. By providing this diversity of corrected transport speeds, the transport speed of the medium 99 can be corrected in both cases: when the medium 99 arrives at the predetermined position early and when the medium 99 arrives at the predetermined position late. Therefore, the transport performance of the medium 99 can be improved.

[0112] (1-3) The control unit 17 causes the second transport unit 22 to transport the medium 99 at the normal transport speed v0 during the normal transport period T2. The control unit 17 causes the second transport unit 22 to transport the medium 99 at the corrected transport speed during the corrected transport period T4. With this configuration, the transport speed of the second transport unit 22 can be made different during the corrected transport period T4 and the normal transport period T2. In this way, by providing diversity in transport speed, the transport speed of the medium 99 can be corrected. Therefore, the transport performance of the medium 99 can be improved.

[0113] (1-4) The normal transport speed v0 is equal to the transport speed at which the medium 99 is transported by the third transport unit 23. The control unit 17 causes the second transport unit 22 to transport the preceding medium 99 and the succeeding medium 99 at the normal transport speed v0 while the trailing end of the preceding medium 99 is being transported by the second transport unit 22. After the transport of the preceding medium 99 by the second transport unit 22 is completed, the control unit 17 causes the second transport unit 22 to transport the succeeding medium 99 at the corrected transport speed. With this configuration, while the trailing end of the preceding medium 99 is being transported by the second transport unit 22, the second transport unit 22 can be made to transport the preceding medium 99 and the succeeding medium 99 at the same normal transport speed v0 as the third transport unit 23. This allows the preceding medium 99 to be transported smoothly between the second transport unit 22 and the third transport unit 23. In particular, the recording unit 16 is configured to record on the medium 99 being transported by the third transport unit 23. Therefore, by smoothly transporting the preceding medium 99 between the second transport unit 22 and the third transport unit 23, the accuracy of recording can be improved. In addition, after the transport of the preceding medium 99 by the second transport unit 22 is completed, the subsequent medium 99 can be transported by the second transport unit 22 at a corrected transport speed. This allows the second transport unit 22 to transport the subsequent medium 99 at a corrected transport speed. Thus, the transport performance of the medium 99 can be improved.

[0114] (1-5) The normal transport speed v0 is slower than the corrected transport speed. With this configuration, after the transport of the preceding medium 99 by the second transport unit 22 is completed, the second transport unit 22 can transport the subsequent medium 99 at a corrected transport speed that is faster than the normal transport speed v0. This allows the second transport unit 22 to increase the transport speed of the subsequent medium 99. In this way, the throughput of the medium 99 can be improved. Therefore, the transport performance of the medium 99 can be improved.

[0115] (1-6) The first transport unit 21 is a transport unit that supplies the medium 99 stored in the medium storage unit 12. The normal transport speed v0 is equal to or greater than the transport speed of the first transport unit 21. With this configuration, the medium 99 can be supplied at an appropriate transport speed, and even if the transport speed by the first transport unit 21 is slowed down, the transport speed can be increased by the second transport unit 22. This allows the transport speed of the medium 99 to be increased by the second transport unit 22. In this way, the throughput of the medium 99 can be improved. Therefore, the transport performance of the medium 99 can be improved. In addition, it is possible to prevent the medium 99 transported by the first transport unit 21 from catching up to the medium 99 transported by the second transport unit 22.

[0116] (1-7) The normal transport speed v0 is slower than the abutment transport speed v3 and the low speed v3. The control unit 17 changes the transport speed by the second transport unit 22 in the order of normal transport speed v0, corrected transport speed, and abutment transport speed v3. With this configuration, the medium 99 can be brought into contact with the resist roller pair 35 at an appropriate transport speed. In addition, by changing the transport speed by the second transport unit 22 in the order of normal transport speed v0, corrected transport speed, and abutment transport speed v3, the medium 99 can be transported at a transport speed appropriate to the situation. Therefore, the transport performance of the medium 99 can be improved.

[0117] (1-8) The reference speed v1 is faster than the transport speed of the first transport unit 21. With this configuration, even if the transport speed by the first transport unit 21 is slowed down, the transport speed can be increased by the second transport unit 22. This allows the transport speed of the medium 99 to be increased by the second transport unit 22. In this way, the throughput of the medium 99 can be improved. Therefore, the transport performance of the medium 99 can be improved.

[0118] (1-9) The low speed v3 is equal to the abutment transport speed v3. With this configuration, the medium 99 can be brought into contact with the resist roller pair 35 at an appropriate transport speed. In addition, by setting the corrected transport speed by the second transport unit 22 to a low speed v3 equal to the abutment transport speed v3, the number of times the transport speed needs to be changed can be reduced. Therefore, the transport performance of the medium 99 can be improved.

[0119] (1-10) The control unit 17 controls the second transport unit 22 to perform curved acceleration and deceleration. With this configuration, the medium 99 can be transported in a way that performs curved acceleration and deceleration. Therefore, the transport performance of the medium 99 can be improved.

[0120] [Second Embodiment] Next, a second embodiment will be described. In the following description, redundant explanations of the same configuration as in the previously described embodiment will be omitted or simplified, and configurations that differ from those in the previously described embodiment will be described.

[0121] As shown in Figure 8, in the second embodiment, a medium transport device 13 may be used in the recording system 10. The recording system 10 comprises a recording device 11, an intermediate device 18, and a post-processing device 19. In other words, the recording system 10 includes a medium transport device 13.

[0122] The intermediate device 18 is a device that transports the medium 99 recorded by the recording unit 16 from the recording device 11 to the post-processing device 19. The intermediate device 18 may also transport the medium 99 inverted to the post-processing device 19.

[0123] The post-processing device 19 is a device that performs post-processing on the medium 99 recorded by the recording unit 16. The post-processing device 19 is an example of a post-processing unit. The post-processing device 19 may be controlled by the control unit 17 of the recording device 11, or it may be controlled by the control unit of the post-processing device 19. In such a case, the recording system 10 only needs to have at least one control unit, and both the recording device 11 and the post-processing device 19 may have control units.

[0124] Post-processing may include, for example, binding, but may also include perforation, folding, shifting, or stacking. Binding is the process of binding multiple media 99 together and then discharging them. Perforation is the process of perforating one or more media 99 and then discharging them. Folding is the process of folding the media 99 and then discharging it. Shifting is the process of shifting the position of the media 99 section by section and then discharging them. Stacking is the process of discharging multiple media 99 sections as a bundle without shifting their position, and also the process of discharging a single media 99 without shifting it.

[0125] <Operation and Effects of the Second Embodiment> The operation and effects of the second embodiment will now be described. (2-1) The recording system 10 includes a post-processing device 19 that performs post-processing on the medium 99 recorded by the recording unit 16. With this configuration, post-processing can be performed on the medium 99 at an appropriate timing by improving the transport performance of the medium 99.

[0126] [Third Embodiment] Next, a third embodiment will be described. In the third embodiment, the transport path 15 is longer than in the first embodiment.

[0127] <Configuration of recording device 11> As shown in Figure 9, in the third embodiment, the transport unit 14 may include a feeding unit 60 and a first transport unit 51. In other words, the recording device 11 and the media transport device 13 may include a feeding unit 60 and a first transport unit 51. The feeding unit 60 is the first transport unit 21 in the first and second embodiments. The feeding unit 60 includes a feeding drive unit 61 and a feeding roller 62. The feeding drive unit 61 is the first transport drive unit 31 in the first and second embodiments. The feeding roller 62 is the feeding roller 30 in the first and second embodiments.

[0128] The first transport unit 51 may be configured to transport the medium 99 supplied from the supply unit 60 to the second transport unit 22. The first transport unit 51 does not have to be located at the uppermost position of the transport path 15. In this case, the first transport unit 51 is located downstream of the supply unit 60 in the transport path 15.

[0129] The first conveying unit 51 comprises a first upstream roller pair 52, a second upstream roller pair 53, and a first conveying drive unit 54. The second upstream roller pair 53 is located downstream of the first upstream roller pair 52. The first conveying drive unit 54 is connected to the first upstream roller pair 52. The first conveying drive unit 54 is connected to the second upstream roller pair 53. The first conveying drive unit 54 is a drive source that rotates the first upstream roller pair 52 and the second upstream roller pair 53. The first conveying drive unit 54 may be a motor.

[0130] The first transport drive unit 54 rotates the first upstream roller pair 52 and the second upstream roller pair 53 by driving based on a drive signal from the control unit 17. The first transport drive unit 54 rotates the first upstream roller pair 52 and the second upstream roller pair 53 to transport the medium 99 in the transport direction D.

[0131] The first upstream roller pair 52 may include a switching unit 55. The second upstream roller pair 53 may also include a switching unit 55. In other words, the first conveying unit 51 may include a switching unit 55. The switching unit 55 may be, for example, a one-way clutch.

[0132] The switching unit 55 allows the rotation of the first upstream roller pair 52 in the direction of transporting the medium 99 to the second transport unit 22. The switching unit 55 also allows the rotation of the second upstream roller pair 53 in the direction of transporting the medium 99 to the second transport unit 22.

[0133] The switching unit 55 can be switched between a driven state and a driven state. Specifically, the driven state is a state in which the first upstream roller pair 52 and the second upstream roller pair 53 rotate by the driving force transmitted from the first transport drive unit 54. In other words, the driven state is a state in which the first upstream roller pair 52 and the second upstream roller pair 53 rotate at a speed controlled by the control unit 17. The driven state is a state in which no driving force is transmitted from the first transport drive unit 54, and the system can be driven by the frictional force with the medium 99 transported by the second transport unit 22. In other words, the driven state is a state in which the system can rotate driven by the medium 99.

[0134] The first upstream roller pair 52 is prevented from rotating in the direction opposite to the direction in which the medium 99 is transported to the second transport unit 22 by the switching unit 55. The second upstream roller pair 53 is prevented from rotating in the direction opposite to the direction in which the medium 99 is transported to the second transport unit 22 by the switching unit 55.

[0135] <Control details of the first transport unit 51 and the second transport unit 22> In the third embodiment, the corrected transport speed includes a reference speed v4 shown in Figure 10 and a high speed v5 shown in Figure 10. The reference speed v4 is slower than the normal transport speed v0. The reference speed v4 is slower than the sudden transport speed v3. The high speed v5 is faster than the normal transport speed v0. The high speed v5 is faster than the sudden transport speed v3.

[0136] Next, specific examples of the control contents of the first transport unit 51 and the second transport unit 22 will be described with reference to Figures 10 and 11. Figure 10 shows a specific example of the control contents of the second transport unit 22. Figure 11 shows a specific example of the control contents of the first transport unit 51.

[0137] As shown in Figure 10, when the transport of the medium 99 by the feeding unit 60 and the first transport unit 51 begins at the timing indicated by the symbol T70, the second transport unit 22 begins transporting the medium 99 at the timing indicated by the symbol T50. Thereafter, the transport speed by the second transport unit 22 is accelerated in a curved manner, and at the timing indicated by the symbol T51, the transport speed by the second transport unit 22 is maintained at the normal transport speed v0.

[0138] If the leading edge of the medium 99 is detected by the first medium detection unit 41 at the timing indicated by the reference arrival time T52, the difference between the arrival time and the reference arrival time becomes 0. As a result, the reference speed v4 is selected from multiple corrected transport speeds, and thereafter, the fifth time t5 is determined as the corrected transport time. Each timing for initiating the adjustment of the transport speed may be determined based on the corrected transport time.

[0139] At the timing indicated by symbol T53, the transport speed by the second transport unit 22 is reduced in a curved manner, and at the timing indicated by symbol T54, it is maintained at the reference speed v4. At the timing indicated by symbol T55, when the fifth time t5 has elapsed from the timing indicated by symbol T54, the transport speed by the second transport unit 22 undergoes a curved acceleration and is maintained at the initial transport speed v3 at the timing indicated by symbol T56. As a result, at a certain timing indicated by symbol T57, the leading edge of the medium 99 is detected by the second medium detection unit 42. At the timing indicated by symbol T58, the transport speed by the second transport unit 22 undergoes a curved deceleration and becomes 0 at the timing indicated by symbol T59.

[0140] As shown in Figure 11, when the conveying unit 60 starts conveying the medium 99 at the timing indicated by symbol T70, the first conveying unit 51 starts conveying the medium 99 at the timing indicated by symbol T71. Thereafter, the conveying speed by the first conveying unit 51 is accelerated in a curved manner and maintained at the normal conveying speed v0 at the timing indicated by symbol T71. The normal conveying speed v0 corresponds to an example of a predetermined conveying speed.

[0141] When a reference speed v4 is selected as the corrected transport speed in the second transport unit 22, the control unit 17 controls the transport speed of the first transport unit 51 to be reduced in a curve at the timing indicated by the symbol T72, and to be maintained at the reference speed v4 at the timing indicated by the symbol T73. The control unit 17 drives the first transport unit 51 at the reference speed v4 for a seventh time t7. The seventh time t7 may be the value used when the first transport unit 51 is driven at the corrected transport speed.

[0142] At the timing indicated by symbol T74, when 7 hours t7 have elapsed since the timing indicated by symbol T73, the control unit 17 reduces the transport speed of the first transport unit 51 in a curved manner, and sets it to 0 at the timing indicated by symbol T75.

[0143] In this case, the driving force from the first transport drive unit 54 is not transmitted to the first upstream roller pair 52 and the second upstream roller pair 53, and the transport speed of the first transport unit 51 becomes 0. On the other hand, the first upstream roller pair 52 and the second upstream roller pair 53 themselves become driven and rotate in accordance with the medium 99 transported to the second transport unit 22. Thus, although the transport speed of the first transport unit 51 may not match the rotational speed of the first transport unit 51 due to the medium 99 transported to the second transport unit 22, in principle it matches the rotational speed of the first transport unit 51.

[0144] On the other hand, as shown in Figure 10, if the leading edge of the medium 99 is detected by the first medium detection unit 41 at the timing indicated by symbol T62 after the reference arrival time has been reached, the difference between the arrival time and the reference arrival time becomes the fifth difference Δt5. In this case, after a high speed v5 is selected from multiple corrected transport speeds, the sixth time t6 is determined as the corrected transport time. The sixth time t6 may be longer than the fifth time t5.

[0145] At the timing indicated by symbol T63, the transport speed of the second transport unit 22 is accelerated in a curved manner, and at the timing indicated by symbol T64, the transport speed of the second transport unit 22 is maintained at a high speed v5.

[0146] At the timing indicated by symbol T65, when the 6th time t6 has elapsed from the timing indicated by symbol T64, the transport speed by the second transport unit 22 is reduced in a curved manner, and at the timing indicated by symbol T66, it is maintained at the initial transport speed v3.

[0147] As shown in Figure 11, when a high speed v5 is selected as the corrected transport speed in the second transport unit 22, the control unit 17 drives the first transport unit 51 at the normal transport speed v0 for 8 hours t8 at the timing indicated by reference numeral T72. The 8 hours t8 may be a value used when the first transport unit 51 is driven at a predetermined transport speed.

[0148] At the timing indicated by symbol T74, when 8 hours t8 have elapsed since the timing indicated by symbol T72, the control unit 17 reduces the drive speed of the first transport unit 51 in a curved manner, and sets it to 0 at the timing indicated by symbol T75.

[0149] Thus, after the medium 99 reaches a predetermined position, the control unit 17 rotates the first transport unit 51 at the reference speed v4 if the corrected transport speed is the reference speed v4. In other words, the control unit 17 rotates the first transport unit 51 at the reference speed v4 if the corrected transport speed is slower than the normal transport speed v0.

[0150] If the corrected transport speed is high speed v5 after the medium 99 has reached a predetermined position, the control unit 17 rotates the first transport unit 51 at the normal transport speed v0. In other words, if the corrected transport speed is equal to or greater than the normal transport speed v0, the control unit 17 rotates the first transport unit 51 at the normal transport speed v0.

[0151] In the third embodiment, the timing indicated by reference numeral T72 in Figure 11 is earlier than the timings indicated by reference numeral T53 and T63 in Figure 10. The timing indicated by reference numeral T73 in Figure 11 is earlier than the timings indicated by reference numeral T54 and T64 in Figure 10, and earlier than the timings indicated by reference numeral T53 and T63 in Figure 10. Thus, the change in the transport speed of the first transport unit 51 is performed before the change in the transport speed of the second transport unit 22. In other words, the control unit 17 changes the transport speed of the first transport unit 51, and then changes the transport speed of the second transport unit 22.

[0152] <Operation and Effects of the Third Embodiment> The operation and effects of the third embodiment will now be described. (3-1) After the medium 99 reaches a predetermined position, if the corrected transport speed is high speed v5, the control unit 17 rotates the first transport unit 51 at normal transport speed v0. After the medium 99 reaches a predetermined position, if the corrected transport speed is standard speed v4, the control unit 17 rotates the first transport unit 51 at standard speed v4.

[0153] With this configuration, if the corrected transport speed of the second transport unit 22 is slower than the normal transport speed v0 of the first transport unit 51, the control unit 17 can control the transport speed of the first transport unit 51 to the reference speed v4, which is the corrected transport speed of the second transport unit 22. As a result, the first transport unit 51 can prevent the rear end of the medium 99 from being transported faster than the front end of the medium 99 when transporting the medium 99 to the second transport unit 22. This allows the first transport unit 51 to transport the medium 99 to the second transport unit 22 at an appropriate speed. Therefore, the transport performance of the medium 99 can be improved.

[0154] (3-2) The control unit 17 changes the transport speed of the second transport unit 22 after changing the transport speed of the first transport unit 51. With this configuration, the control unit 17 can change the transport speed of the second transport unit 22 in accordance with the transport speed of the first transport unit 51. As a result, the first transport unit 51 can suppress the transport of the rear end of the medium 99 to the second transport unit 22 at a faster speed than the front end of the medium 99 when transporting the medium 99. Therefore, the transport performance of the medium 99 can be improved.

[0155] [Example of changes] This embodiment can be implemented with the following modifications. This embodiment and the following modifications can be combined with each other to the extent that they do not contradict each other technically.

[0156] In the second embodiment, the intermediate device 18 may perform post-processing on the medium 99. The recording device 11 may perform post-processing on the medium 99. The post-processing may be a process of inverting and transporting the medium 99. The post-processing may be a process of inverting and transporting the medium 99, but it may also be, for example, a binding process, a punching process, a folding process, a shifting process, or a bar stacking process.

[0157] The control unit 17 may correct the transport speed by the second transport unit 22 when the difference exceeds or falls below the allowable range. The control unit 17 may select a high speed v2 as the corrected transport speed by the second transport unit 22 when the difference exceeds the allowable range. The control unit 17 may select a reference speed v1 as the corrected transport speed by the second transport unit 22 and calculate the corrected transport time when the difference exceeds the allowable range. The control unit 17 may select a low speed v3 as the corrected transport speed by the second transport unit 22 when the difference falls below the allowable range. The control unit 17 may select a reference speed v1 as the corrected transport speed by the second transport unit 22 and calculate the corrected transport time when the difference falls below the allowable range. The control unit 17 may select a reference speed v1 as the corrected transport speed by the second transport unit 22 and set the corrected transport time to a constant time when the difference is within the allowable range. The allowable range may be a first range. The allowable range may be included in the first range.

[0158] The control unit 17 does not have to select the low speed v3 as the corrected transport speed by the second transport unit 22 when the difference is a negative number. In other words, the control unit 17 may select the high speed v2 as the corrected transport speed by the second transport unit 22 when the difference is a positive number.

[0159] The control unit 17 does not have to select high speed v2 as the corrected transport speed by the second transport unit 22 when the difference is a positive value. In other words, the control unit 17 may select low speed v3 as the corrected transport speed by the second transport unit 22 when the difference is a negative value.

[0160] The transport speed of the medium 99 by the resist roller pair 35 and the transport speed of the medium 99 by the medium support unit 37 may be different. The normal transport speed v0 may be equal to the transport speed of the medium 99 by the resist roller pair 35, or it may be equal to the transport speed of the medium 99 by the medium support unit 37.

[0161] The control unit 17 may control the third transport unit 23 to temporarily stop transporting the medium 99 before recording onto the medium 99. Alternatively, the control unit 17 may control the third transport unit 23 to continue transporting the medium 99.

[0162] • Low speed v3 may be faster than the initial transport speed v3. Low speed v3 may be slower than the initial transport speed v3. Low speed v3 may be faster than the normal transport speed v0 and slower than the initial transport speed v3. Low speed v3 may be equal to the normal transport speed v0. Initial transport speed v3 may be equal to the normal transport speed v0.

[0163] The corrected transport speed may consist of two or more types of transport speeds. The corrected transport speed may include two or more high speeds that are faster than the reference speed. The corrected transport speed may also include two or more low speeds that are slower than the reference speed.

[0164] The control unit 17 may select a different speed as the corrected transport speed based on the transport conditions. The transport conditions may include the size of the medium 99, such as the length of the medium 99 in the transport direction D. The transport conditions may also include the type of medium 99, such as plain paper or cardboard. The transport conditions may also include the position of the medium storage unit 12 in which the medium 99 is transported among a plurality of medium storage units 12. In other words, the transport conditions may include the distance from the first transport unit 21 to a predetermined position.

[0165] The normal transport speed v0 may be faster than the transport speed of the medium 99 by the first transport unit 21, or equal to the transport speed of the medium 99 by the first transport unit 21, or it may be slower than the transport speed of the medium 99 by the first transport unit 21.

[0166] The corrected transport data shown in Figure 2 is predetermined as normal transport data, and the control unit 17 may generate corrected transport data when the difference is not zero, as shown in Figures 3 to 5, and control the second transport unit 22 based on the corrected transport data.

[0167] The control unit 17 may perform any process to determine the corrected transport time based on the difference and the corrected transport time. For example, if the control unit 17 has determined the reference speed v1 as the corrected transport speed, it may determine the corrected transport time based on the first time t1, which is the corrected transport time shown in Figure 2, the difference, and the corrected transport speed. Specifically, the control unit 17 identifies the corrected transport distance based on the difference. The corrected transport distance is the transport distance required to bring the leading edge of the medium 99 to the detection position at a predetermined second detection timing, compared with the transport data shown in Figure 2. The control unit 17 calculates the time to correct to the first time t1 based on the corrected transport distance and the corrected transport speed. Thus, the control unit 17 may calculate the corrected transport time based on the first time t1 and the time to correct to the first time t1.

[0168] The second transport drive unit 34 may separately include a drive source for rotating the first roller pair 32 and a drive source for rotating the second roller pair 33. The second transport drive unit 34 may be a drive source that rotates at least one of the first roller pair 32. The second transport drive unit 34 may be a drive source that rotates at least one of the second roller pair 33.

[0169] The first conveying section 21 may be equipped with a pair of separating rollers in addition to the feeding rollers 30. The second conveying section 22 may be equipped with a third pair of rollers in addition to the first pair of rollers 32 and the second pair of rollers 33. The second conveying section 22 may be equipped with the first pair of rollers 32 but not with the second pair of rollers 33.

[0170] The first transport unit 21 does not have to be a supply unit that transports the medium 99 from the medium storage unit 12. The first transport unit 21 may be configured to transport the medium 99 transported from the supply unit. In other words, the first transport unit 21 does not have to be located at the uppermost position of the transport path 15. Thus, the arrival time is the time when the leading edge of the medium 99 reaches a predetermined position with respect to the start of transport of the medium 99, but it may also be the time from when the leading edge of the medium 99 reaches a predetermined position by the first transport unit 21 until the leading edge of the medium 99 reaches the predetermined position.

[0171] The predetermined position may be located upstream of the first roller pair 32, as long as it is downstream of the first transport unit 21. The detection position may be any predetermined position downstream of the second transport unit 22, and does not have to be a position where the leading edge of the medium 99 is detected by the second medium detection unit 42.

[0172] The resist roller pair 35 may be provided between the second transport section 22 and the third transport section 23. In this case, the third transport section 23 does not need to be equipped with the resist roller pair 35. In other words, the second transport section 22, the resist roller pair 35, and the third transport section 23 may be provided in the order from upstream to downstream.

[0173] The second medium detection unit 42 does not necessarily have to be located a short distance upstream of the register roller pair 35. The medium transport device 13 does not necessarily have to include the register roller pair 35. In such cases, the second medium detection unit 42 may be located upstream of the third transport unit 23.

[0174] The third transport unit 23 may be located downstream of the recording unit 16. The second transport unit 22 may be located downstream of the recording unit 16. The first transport unit 21 may be located downstream of the recording unit 16.

[0175] The transport unit 14 may include a fourth transport unit (not shown). The fourth transport unit may be provided between the first transport unit 21 and the second transport unit 22. The fourth transport unit may be provided between the second transport unit 22 and the third transport unit 23.

[0176] In the third embodiment, the first upstream roller pair 52 may have one roller in the pair equipped with a switching section 55, or both rollers may be equipped with a switching section 55. The second upstream roller pair 53 may have one roller in the pair equipped with a switching section 55, or both rollers may be equipped with a switching section 55. The first upstream roller pair 52 does not need to be equipped with a switching section 55. The second upstream roller pair 53 does not need to be equipped with a switching section 55.

[0177] In the third embodiment, the first roller pair 32 may include a switching section 55. In the third embodiment, the second roller pair 33 may include a switching section 55. In the first roller pair 32, one of the rollers in the pair may include a switching section 55, or both may include a switching section 55. In the second roller pair 33, one of the rollers in the pair may include a switching section 55, or both may include a switching section 55.

[0178] In the third embodiment, the transport speed of the first transport unit 51, denoted by reference numeral T72 in Figure 11, may be faster than the normal transport speed v0. For example, if the corrected transport speed is high speed v5 after the medium 99 has reached a predetermined position, the control unit 17 may set the first transport unit 51 to high speed v5. For example, if the corrected transport speed is high speed v5 after the medium 99 has reached a predetermined position, the control unit 17 may set the first transport unit 51 to a speed faster than the normal transport speed v0 and less than or equal to high speed v5.

[0179] In the third embodiment, the transport speed by the first transport unit 51, denoted by reference numeral T71 in Figure 11, may be slower than the normal transport speed v0. In other words, the predetermined transport speed may be slower than the normal transport speed v0. The transport speed by the first transport unit 51, denoted by reference numeral T71 in Figure 11, may be faster than the normal transport speed v0. In other words, the predetermined transport speed may be faster than the normal transport speed v0.

[0180] In the third embodiment, the first transport drive unit 54 and the second transport drive unit 34 may be controlled via the same control board or via different control boards. When the first transport drive unit 54 and the second transport drive unit 34 are controlled via different control boards, even if there is an error due to a delay between the control timing of the first transport drive unit 54 and the control timing of the second transport drive unit 34, the medium 99 can be transported smoothly. In the third embodiment, the first transport unit 51 may be controlled by a different control unit than the second transport unit 22. In other words, the recording device 11 and the medium transport device 13 may have multiple control units.

[0181] In the third embodiment, the control unit 17 may change the transport speed of the second transport unit 22 when the transport speed of the first transport unit 51 is changed. The control unit 17 may change the transport speed of the first transport unit 51 after changing the transport speed of the second transport unit 22.

[0182] In the third embodiment, the recording device 11 may include two or more media storage units 12. Some of the two or more media storage units 12 may be provided so that the media 99 can be directly transported to the second transport unit 22 without passing through the first transport unit 51. In this case, the recording device 11 and the media transport device 13 may include as many feeding units 60 as there are media storage units 12.

[0183] In the third embodiment, the recording device 11 and the media transport device 13 may be provided with two or more first transport units 51. The recording device 11 and the media transport device 13 may be provided with two or more first transport units 51 for one media storage unit 12, or with one or more first transport units 51 for each of two or more media storage units 12.

[0184] The medium 99 may be paper, resin films or sheets, composite films of resin and metal, laminate films, textiles, nonwoven fabrics, metal foils, metal films, ceramic sheets, and clothing.

[0185] The liquid can be any liquid that can adhere to the medium 99 and allow for recording on the medium 99. For example, ink includes functional material particles consisting of solids such as pigments and metal particles dissolved, dispersed, or mixed in a solvent, and encompasses various compositions such as water-based inks, oil-based inks, gel inks, and hot-melt inks.

[0186] A lateral printer may be used as the recording device 11. A lateral printer is a printer in which the carriage can move in two directions, the X-axis direction and the Y-axis direction. The recording device 11 is not limited to an inkjet printer, but may also be a dot matrix printer. The recording device 11 may also be a laser printer.

[0187] The media transport device 13 may be used in an intermediate device 18, other than the recording device 11. The media transport device 13 may be used in a post-processing device 19. The media transport device 13 may be used in an image reading device.

[0188] As used herein, the expression "at least one of" means one or more of the desired options. For example, as used herein, if there are two options, the expression "at least one of" means either one option or both of the two options. As another example, as used herein, if there are three or more options, the expression "at least one of" means either one option or any combination of two or more options.

[0189] [Note] The following describes the technical concepts and their effects as understood from the embodiments and modifications described above. These technical concepts and their effects can be combined with each other to the extent that they do not contradict each other.

[0190] [1] The media transport device comprises a transport unit for transporting media and a control unit for controlling the transport unit, wherein the transport unit has a first transport unit for transporting media and a second transport unit for transporting media downstream of the first transport unit, and the control unit selects a transport speed for the media by the second transport unit from a predetermined number of corrected transport speeds based on the difference between the time the media arrives at a predetermined position downstream of the first transport unit and a reference arrival time, and calculates a corrected transport time for transporting the media at the corrected transport speed based on the difference and the selected corrected transport speed.

[0191] This configuration allows the transport speed of the medium by the second transport unit to be selected from a predetermined range of corrective transport speeds based on the difference between the medium's arrival time at a predetermined location and a reference arrival time. Subsequently, the corrective transport time for transporting the medium at the corrective transport speed can be calculated based on the difference and the corrective transport speed. This enables smooth acceleration and deceleration corresponding to the selected corrective transport speed, and by adjusting the corrective transport speed, the medium can be transported at the appropriate timing. Therefore, when correcting the transport speed, the complexity of calculating the corrective transport speed can be suppressed. Consequently, the transport performance of the medium can be improved.

[0192] In addition, once a medium reaches a predetermined position, it can be transported at a corrected transport speed based on the difference between the arrival time and the reference arrival time. Therefore, the transport performance of the medium can be improved.

[0193] [2] The media transport device described above, wherein the corrected transport speed may include a reference speed based on the reference arrival time, a high speed faster than the reference speed, and a low speed slower than the reference speed.

[0194] With this configuration, the corrected transport speed can be controlled to a high speed that is faster than the reference speed based on the reference arrival time, and a low speed that is slower than the reference speed based on the reference arrival time. By providing this diversity in corrected transport speeds, the transport speed of the medium can be corrected both when the medium arrives at a predetermined position early and when the medium arrives at a predetermined position late. Therefore, the transport performance of the medium can be improved.

[0195] [3] In the media transport device described above, the control unit may cause the second transport unit to transport the medium at the corrected transport speed during the corrected transport period based on the corrected transport time, and cause the second transport unit to transport the medium at the normal transport speed during the normal transport period which is not the corrected transport period.

[0196] This configuration allows for different transport speeds during the corrected transport period and the normal transport period. By providing this diversity in transport speeds, the transport speed of the media can be corrected. Therefore, the transport performance of the media can be improved.

[0197] [4] The media transport device described above, wherein the transport unit further has a third transport unit that transports media downstream of the second transport unit, the normal transport speed is equal to the transport speed at which the media is transported by the third transport unit, and when the control unit has a plurality of media, including a preceding medium and a succeeding medium, transported by the second transport unit, the control unit may have the second transport unit transport the preceding medium and the succeeding medium at the normal transport speed during the period when the second transport unit is transporting the trailing end of the preceding medium, and after the transport of the preceding medium by the second transport unit is completed, the control unit may have the second transport unit transport the succeeding medium at the corrected transport speed.

[0198] With this configuration, while the trailing end of the preceding medium is being transported by the second transport unit, the preceding medium and the succeeding medium can be transported by the second transport unit at the same normal transport speed as the third transport unit. This allows for smooth transport of the preceding medium between the second and third transport units. In addition, after the transport of the preceding medium by the second transport unit is complete, the succeeding medium can be transported by the second transport unit at a corrected transport speed. This allows the second transport unit to transport the succeeding medium at a corrected transport speed. Therefore, the transport performance of the medium can be improved.

[0199] [5] In the above-mentioned media transport device, the normal transport speed may be slower than the corrected transport speed. With this configuration, after the second transport unit has completed transporting the preceding medium, the second transport unit can transport the subsequent medium at a corrected transport speed faster than the normal transport speed. This allows the second transport unit to transport the subsequent medium at a faster speed. Therefore, the transport performance of the medium can be improved.

[0200] [6] The media transport device described above, wherein the first transport unit is a supply unit that supplies the media stored in the media storage unit, and the normal transport speed may be equal to or greater than the transport speed of the supply unit.

[0201] This configuration allows for the feeding of the medium at an appropriate conveying speed, and even when the conveying speed by the feeding unit is slowed down, the second conveying unit can increase the conveying speed. As a result, the conveying speed of the medium can be increased by the second conveying unit. Therefore, the conveying performance of the medium can be improved.

[0202] [7] The media transport device described above, wherein the transport unit is provided downstream of the second transport unit and further includes a pair of resist rollers against which the media transported by the second transport unit abuts, the normal transport speed is slower than the abutment transport speed when the second transport unit abuts the media against the pair of resist rollers and the low speed, and the control unit may change the transport speed by the second transport unit in the order of the normal transport speed, the corrected transport speed, and the abutment transport speed.

[0203] This configuration allows the medium to be brought into contact with the resist roller pair at an appropriate transport speed. In addition, by changing the transport speed of the second transport unit in the order of normal transport speed, corrected transport speed, and contact transport speed, the medium can be transported at a transport speed appropriate to the situation. Therefore, the transport performance of the medium can be improved.

[0204] [8] The media transport device described above, wherein the first transport unit is a supply unit that supplies the media stored in the media storage unit, and the reference speed may be faster than the transport speed of the supply unit. With this configuration, even if the conveying speed by the feeding unit is slowed down, the conveying speed can be increased by the second conveying unit. This allows the conveying speed of the medium to be increased by the second conveying unit. Therefore, the conveying performance of the medium can be improved.

[0205] [9] The media transport device described above, wherein the transport section is provided downstream of the second transport section and further comprises a pair of resist rollers against which the media transported by the second transport section abuts, and the low speed may be equal to the abutment transport speed when the second transport section abuts the media against the pair of resist rollers.

[0206] This configuration allows the medium to be brought into contact with the resist roller pair at an appropriate transport speed. In addition, by setting the corrective transport speed by the second transport unit to a low speed equal to the contact transport speed, the number of times the transport speed needs to be changed can be reduced. Therefore, the transport performance of the medium can be improved.

[0207]

[10] In the above-mentioned media transport device, the control unit may control the second transport unit to perform curved acceleration and deceleration. This configuration allows the medium to be transported in a way that enables curved acceleration and deceleration. Therefore, the transport performance of the medium can be improved.

[0208]

[11] The media transport device described above, wherein the transport unit is provided downstream of the second transport unit and further comprises a pair of resist rollers against which the media transported by the second transport unit abuts, and the first transport unit may be a supply unit that supplies the media contained in the media storage unit.

[0209] This configuration allows for the medium to be fed at an appropriate transport speed and to be brought into contact with the resist roller pair at an appropriate transport speed. Therefore, the transport performance of the medium can be improved.

[0210]

[12] The media transport device described above, wherein the first transport unit has a switching unit that can switch between a driven state in which it rotates at a speed controlled by the control unit and a driven state in which it can rotate in accordance with the media, and the control unit rotates the first transport unit at the predetermined transport speed if the corrected transport speed is equal to or greater than the predetermined transport speed after the media has reached the predetermined position, and rotates the first transport unit at the corrected transport speed if the corrected transport speed is slower than the predetermined transport speed.

[0211] With this configuration, if the corrected transport speed of the second transport unit is slower than the transport speed of the first transport unit, the control unit can control the transport speed of the first transport unit to match the corrected transport speed of the second transport unit. As a result, the first transport unit can transport the medium at an appropriate speed relative to the second transport unit. Therefore, the transport performance of the medium can be improved.

[0212]

[13] The media transport device described above, wherein the first transport unit has a switching unit that can switch between a driven state in which it rotates at a speed controlled by the control unit and a driven state in which it can rotate in accordance with the media, and the control unit rotates the first transport unit at a predetermined transport speed if the corrected transport speed is equal to or greater than the normal transport speed after the media has reached the predetermined position, and rotates the first transport unit at the corrected transport speed if the corrected transport speed is slower than the normal transport speed. With this configuration, the same effect as in

[12] can be achieved.

[0213]

[14] In the above-described media transport device, the control unit changes the transport speed of the second transport unit after changing the transport speed of the first transport unit. With this configuration, the control unit can change the transport speed of the second transport unit in accordance with the transport speed of the first transport unit. Therefore, the transport performance of the media can be improved.

[0214]

[15] The recording device comprises a transport unit for transporting a medium, a recording unit for recording on the medium transported by the transport unit, and a control unit for controlling the transport unit and the recording unit, wherein the transport unit has a first transport unit for transporting a medium and a second transport unit for transporting a medium downstream of the first transport unit, and the control unit selects a transport speed for the medium by the second transport unit from a predetermined number of corrected transport speeds based on the difference between the time the medium arrives at a predetermined position downstream of the first transport unit and a reference arrival time, and calculates a corrected transport time for transporting the medium at the corrected transport speed based on the difference and the selected corrected transport speed.

[0215] This configuration can produce the same effect as [1]. In addition, by improving the transport performance of the medium, recording can be performed on the medium at the appropriate timing.

[0216]

[16] The recording device described above, wherein the transport unit further has a third transport unit that transports a medium downstream of the second transport unit, and the recording unit may perform recording on the medium transported by the third transport unit. This configuration can achieve the same effects as

[15] .

[0217]

[17] The recording system comprises a transport unit for transporting a medium, a recording unit for recording on the medium transported by the transport unit, a post-processing unit for performing post-processing on the medium recorded by the recording unit, and a control unit for controlling the transport unit, the recording unit, and the post-processing unit, wherein the transport unit comprises a first transport unit for transporting a medium and a second transport unit for transporting a medium downstream of the first transport unit, and the control unit selects a transport speed for the medium by the second transport unit from a predetermined number of corrected transport speeds based on the difference between the time the medium arrives at a predetermined position downstream of the first transport unit and a reference arrival time, and calculates a corrected transport time for transporting the medium at the corrected transport speed based on the difference and the selected corrected transport speed.

[0218] This configuration can produce the same effect as [1]. In addition, by improving the transport performance of the medium, post-processing can be performed on the medium at the appropriate timing.

[0219]

[18] A control method for a media transport device comprising a first transport unit that transports a medium and a second transport unit that transports the medium downstream of the first transport unit, the method comprising: selecting the transport speed of the medium by the second transport unit from a predetermined number of corrected transport speeds based on the difference between the time the medium arrives at a predetermined position downstream of the first transport unit and a reference arrival time; and calculating a corrected transport time for transporting the medium at the corrected transport speed based on the difference and the selected corrected transport speed. This configuration can achieve the same effect as [1]. [Explanation of Symbols]

[0220] 10...Recording system, 11...Recording device, 12...Media storage unit, 13...Media transport device, 14...Transport unit, 15...Transport path, 16...Recording unit, 17...Control unit, 18...Intermediate device, 19...Post-processing device, 21...First transport unit, 22...Second transport unit, 23...Third transport unit, 24...Discharge transport unit, 30...Feeding roller, 31...First transport drive unit, 32...First roller pair, 33...Second roller pair, 34...Second transport drive unit, 35...Resist roller pair, 36...Third transport drive unit, 37...Media support unit, 38...Transport belt, 39...Pulley, 40...Discharge roller pair, 41...First media detection unit, 42...Second media detection unit, 51...First transport unit, 52...First upstream roller pair, 53...Second upstream roller Δt2...1st transport drive unit, 55...Switching unit, 60...Feeding unit, 61...Feeding drive unit, 62...Feeding roller, 99...Medium, D...Transportation direction, t1...1st time, t2...2nd time, t3...3rd time, t4...4th time, t5...5th time, t6...6th time, t7...7th time, t8...8th time, T1...1st acceleration period, T2...Normal transport period, T3...2nd acceleration period, T4...Correction transport period, T5...1st deceleration period, T6...Sudden impact transport period, T7...2nd deceleration period, Δt2...2nd difference, Δt3...3rd difference, Δt4...4th difference, Δt5...5th difference, v0...Normal transport speed, v1...Reference speed, v2...High speed, v3...Low speed, v3...Sudden impact transport speed, v4...Reference speed, v5...High speed.

Claims

1. A transport unit that transports the media, A control unit that controls the transport unit, Equipped with, The transport unit comprises a first transport unit for transporting the medium and a second transport unit for transporting the medium downstream of the first transport unit. The control unit, Based on the difference between the time the medium arrives at a predetermined position downstream of the first transport unit and the reference arrival time, the transport speed of the medium by the second transport unit is selected from a predetermined set of multiple types of corrected transport speeds. Based on the difference and the selected corrected transport speed, the corrected transport time for transporting the medium at the corrected transport speed is calculated. A media transport device characterized by the following features.

2. A media transport device according to claim 1, The corrected transport speed includes a reference speed based on the reference arrival time, a high speed faster than the reference speed, and a low speed slower than the reference speed. A media transport device characterized by the following features.

3. A media transport device according to claim 2, The control unit, During the corrected transport period based on the corrected transport time, the medium is transported to the second transport unit at the corrected transport speed. During the normal transport period, which is not the corrected transport period, the medium is transported to the second transport unit at the normal transport speed. A media transport device characterized by the following features.

4. A media transport device according to claim 3, The transport unit further includes a third transport unit that transports the medium downstream of the second transport unit. The normal transport speed is equal to the transport speed at which the medium is transported by the third transport unit. The control unit, When transporting multiple media, including a preceding medium and a succeeding medium, to the second transport unit, During the period in which the trailing end of the preceding medium is being transported by the second transport unit, the second transport unit is made to transport the preceding medium and the following medium at the normal transport speed. After the transport of the preceding medium by the second transport unit is completed, the subsequent medium is transported by the second transport unit at the corrected transport speed. A media transport device characterized by the following features.

5. A media transport device according to claim 4, The normal transport speed is slower than the corrected transport speed. A media transport device characterized by the following features.

6. A media transport device according to any one of claims 3 to 5, The first transport unit is a transport unit that transports the medium stored in the medium storage unit, The normal transport speed is equal to or greater than the transport speed of the feeding unit. A media transport device characterized by the following features.

7. A media transport device according to any one of claims 3 to 5, The transport unit is located downstream of the second transport unit and further comprises a pair of resist rollers against which the medium transported by the second transport unit abuts. The normal transport speed is slower than the abutment transport speed when the second transport unit abuts the medium against the pair of resist rollers and the low speed. The control unit changes the transport speed of the second transport unit in the order of the normal transport speed, the corrected transport speed, and the sudden transport speed. A media transport device characterized by the following features.

8. A media transport device according to any one of claims 2 to 5, The first transport unit is a transport unit that transports the medium stored in the medium storage unit, The aforementioned reference speed is faster than the conveying speed of the feeding unit. A media transport device characterized by the following features.

9. A media transport device according to any one of claims 2 to 5, The transport unit is located downstream of the second transport unit and further comprises a pair of resist rollers against which the medium transported by the second transport unit abuts. The low speed is equal to the abutment transport speed when the second transport unit abuts the medium against the pair of resist rollers. A media transport device characterized by the following features.

10. A media transport device according to any one of claims 1 to 5, The control unit controls the second transport unit to perform curved acceleration and deceleration. A media transport device characterized by the following features.

11. A media transport device according to any one of claims 1 to 5, The transport unit is located downstream of the second transport unit and further comprises a pair of resist rollers against which the medium transported by the second transport unit abuts. The first transport unit is a transport unit that transports the medium stored in the medium storage unit. A media transport device characterized by the following features.

12. A media transport device according to any one of claims 1 to 5, The first transport unit has a switching unit that can switch between a driven state in which it rotates at a speed controlled by the control unit and a driven state in which it can rotate in accordance with the medium. The control unit, after the medium reaches the predetermined position, If the corrected transport speed is equal to or greater than the predetermined transport speed, the first transport unit is rotated at the predetermined transport speed. If the corrected transport speed is slower than the predetermined transport speed, the first transport unit is rotated at the corrected transport speed. A media transport device characterized by the following features.

13. A media transport device according to any one of claims 3 to 5, The first transport unit has a switching unit that can switch between a driven state in which it rotates at a speed controlled by the control unit and a driven state in which it can rotate in accordance with the medium. The control unit, after the medium reaches the predetermined position, If the corrected transport speed is greater than or equal to the normal transport speed, the first transport unit is rotated at a predetermined transport speed. If the corrected transport speed is slower than the normal transport speed, the first transport unit is rotated at the corrected transport speed. A media transport device characterized by the following features.

14. A media transport device according to claim 12, The control unit changes the transport speed of the second transport unit after changing the transport speed of the first transport unit. A media transport device characterized by the following features.

15. A transport unit that transports the media, A recording unit that records on a medium transported by the transport unit, A control unit that controls the transport unit and the recording unit, Equipped with, The transport unit comprises a first transport unit for transporting the medium and a second transport unit for transporting the medium downstream of the first transport unit. The control unit, Based on the difference between the time the medium arrives at a predetermined position downstream of the first transport unit and the reference arrival time, the transport speed of the medium by the second transport unit is selected from a predetermined set of multiple types of corrected transport speeds. Based on the difference and the selected corrected transport speed, the corrected transport time for transporting the medium at the corrected transport speed is calculated. A recording device characterized by the following features.

16. A recording device according to claim 15, The transport unit further includes a third transport unit that transports the medium downstream of the second transport unit. The recording unit records on the medium transported by the third transport unit. A recording device characterized by the following features.

17. A transport unit that transports the media, A recording unit that records on a medium transported by the transport unit, A post-processing unit that performs post-processing on the medium recorded by the recording unit, A control unit that controls the transport unit, the recording unit, and the post-processing unit, Equipped with, The transport unit comprises a first transport unit for transporting the medium and a second transport unit for transporting the medium downstream of the first transport unit. The control unit, Based on the difference between the time the medium arrives at a predetermined position downstream of the first transport unit and the reference arrival time, the transport speed of the medium by the second transport unit is selected from a predetermined set of multiple types of corrected transport speeds. Based on the difference and the selected corrected transport speed, the corrected transport time for transporting the medium at the corrected transport speed is calculated. A recording system characterized by the following features.

18. A control method for a media transport device comprising a first transport unit for transporting a medium and a second transport unit for transporting a medium downstream of the first transport unit, Based on the difference between the time the medium arrives at a predetermined position downstream of the first transport unit and the reference arrival time, the transport speed of the medium by the second transport unit is selected from a predetermined number of corrected transport speeds. This includes calculating a corrected transport time for transporting the medium at the corrected transport speed, based on the difference and the selected corrected transport speed. A control method for a media transport device, characterized by the following:

Images