JP7684176B2 - Media supply mechanism - Google Patents

Description

The present invention relates to a media supply mechanism.

In the past, a paper feeder for an image forming device has been proposed in which, when a detection switch determines that a no-feed jam has occurred, the drive control unit stops the rotation of the paper feed roller, returns the paper to the paper storage unit using a return roller, and then controls the paper feed roller to rotate again (see, for example, Patent Document 1).

JP 2004-51347 A

In a media supply unit that uses air blowing to lift multiple sheets of media, including the topmost medium, loaded on a stacking platform and transports the lifted topmost medium using a transport belt, if the media is not well adhered to the transport belt and transported with low suction power, a sheet of media may move forward at least a little, but may not reach the entrance passage detection sensor located on the transport path within the specified time, resulting in a determination of empty transport. Such empty transport determinations can also occur with other supply methods, such as the above-mentioned supply method that uses rollers to supply media.

If the media is determined to be running free when it has already been transported close to the entrance passage detection sensor, even if the transport belt is stopped quickly, some of the media may be transported before it completely stops, and may reach the transport rollers installed in the transport path before it stops. In this case, the media that should have been stopped due to being determined to be running free will continue to be transported.

If the time it takes for the media to be detected by the entrance passage detection sensor is slower than the reference passage time, the transport speed can be increased to make the time it takes for the media to reach the intake transport section, such as a pair of registration rollers, closer to constant.

However, if the time at which the media is detected is significantly delayed compared to the reference passing time, it becomes necessary to increase the transport speed accordingly, which may exceed the upper limit of the motor's performance. Even if transport is performed with the transport speed set to the upper limit of the motor's allowable speed, it will be slower than the transport speed required to make up for the delay, so the passing time of the passage detection sensor downstream in the transport direction from the entrance passing detection sensor will also be delayed, resulting in a jam determination. Furthermore, it will no longer be possible to match the arrival time at which the media arrives at the intake transport section.

The object of the present invention is to provide a media supply mechanism that can reliably transport delayed-supplied media with a simple configuration.

In one aspect, the medium supply mechanism includes a supply unit that supplies a medium, a transport path connected to the supply unit, a transport unit that transports the medium on the transport path, a transport drive unit that drives the transport unit, an entry detection sensor that detects that the medium supplied from the supply unit has entered the transport path, an intake transport unit that takes in the medium transported by the transport unit, and a control unit that controls the supply unit and the intake transport unit, and the control unit controls the intake transport unit to take in the medium when the time at which the entry of the medium is detected by the entry detection sensor is within a predetermined first range, and the control unit controls the supply unit to delay the supply of the next medium to be transported and controls the intake transport unit to delay the intake time of the medium when the time at which the entry of the medium is detected by the entry detection sensor is within a second range that is beyond the first range.

According to the above aspect, delayed medium can be transported reliably with a simple configuration.

FIG. 1 is a diagram illustrating an internal configuration of a printing system according to an embodiment. FIG. 2 is a diagram illustrating a control configuration of a medium supplying device and a printing device according to an embodiment. FIG. 2 is a diagram showing an internal configuration of a first supply unit (second supply unit) in one embodiment. 10 is a flowchart illustrating a medium supply operation according to an embodiment. 11 is a timing chart for explaining a retry mode 2 in an embodiment. 1 is a timing chart for explaining a retry mode 1 in an embodiment. 11 is a timing chart for explaining a comparative example. FIG. 11 is a diagram (part 1) showing the relationship between the transport speed and elapsed time to explain correction of the transport speed in one embodiment. FIG. 11 is a diagram (part 2) showing the relationship between the transport speed and elapsed time to explain correction of the transport speed in the embodiment. FIG. 11 is a diagram (part 1) showing the internal configuration of the first supply section (second supply section) to explain the blocking of the blowing of floating air in one embodiment. FIG. 11 is a second diagram showing the internal configuration of the first supply section (second supply section) to explain the blocking of the blowing of floating air in one embodiment. 10A and 10B are diagrams illustrating the positional relationship of a medium during transport in one embodiment. 11 is a table (part 1) for explaining rescheduling of the allowable time of each sensor in one embodiment. 13 is a table (part 2) for explaining rescheduling of the allowable time of each sensor in one embodiment. 13 is a table (part 3) for explaining rescheduling of the allowable time of each sensor in one embodiment. 13 is a table (part 4) for explaining rescheduling of the allowable time of each sensor in one embodiment. 13 is a diagram showing the relationship between the transport speed and the elapsed time when the entry detection time is not corrected within a second range. FIG. FIG. 13 is a diagram showing the relationship between the transport speed and elapsed time to explain the stop of transport in another embodiment. 13 is a table for explaining rescheduling of the allowable time of each sensor in another embodiment.

Below, a media supply mechanism according to one embodiment and another embodiment of the present invention will be described with reference to the drawings.

<One embodiment>
FIG. 1 is a diagram showing the internal configuration of a printing system 100. As shown in FIG.

Figure 2 shows the control configuration of the medium supply device 1 and the printing device 101.

Figure 3 shows the internal configuration of the first supply unit 11 (second supply unit 12).

Note that the front-back, up-down, and left-right directions shown in Figures 1 and 3 and Figures 10A and 10B described later are merely directions for the convenience of explanation, but for example, the front-back and left-right directions are horizontal directions, and the up-down direction is vertical directions.

The printing system 100 shown in FIG. 1 includes a medium supply device 1 and a printing device 101. As will be described in detail later, the medium supply mechanism in this embodiment includes the medium supply device 1, a transport path configuration to the registration roller pair 131 of the printing device 101 (receiving roller pair 132, registration roller pair 131, registration sensor S30, and junction transport path P3), and a control unit 151 of the printing device 101.

The medium supply mechanism supplies medium M downstream in the transport direction from the registration roller pair 131 of the printing device 101 (one example of a supply destination of medium M). Note that the supply destination device of medium M is not limited to the printing device 101, and may be other devices such as a transport device or post-processing device. Also, the medium supply device 1 may be provided integrally with a supply destination device such as the printing device 101. Also, the medium M may be, for example, paper (sheets), but may also be other sheet-like media such as film.

As shown in FIG. 1, the medium supply device 1 includes a first supply unit 11, a second supply unit 12, a first individual transport path P1, a second individual transport path P2, a merging transport path P3, first to ninth transport roller pairs 21 to 29, first to fourth transport drive units D1 to D4, a first entrance passage detection sensor S11, first intermediate passage detection sensors S12 to S14, a first exit passage detection sensor S15, a second entrance passage detection sensor S21, second intermediate passage detection sensors S22 and S23, and a second exit passage detection sensor S24. As shown in FIG. 2, the medium supply device 1 further includes a control unit 31, a memory unit 32, and an interface unit 33.

The medium supply device 1 is divided into an upper tier 1a and a lower tier 1b, with the first supply unit 11 disposed in the upper tier 1a and the second supply unit 12 disposed in the lower tier 1b. In this manner, the first supply unit 11 and the second supply unit 12 are disposed side by side one above the other. The first supply unit 11 and the second supply unit 12 are examples of a supply unit that supplies the medium M. This supply unit may be a single supply unit or three or more supply units.

As shown in FIG. 3, the first supply unit 11 and the second supply unit 12 each have a loading platform 11a, 12a, a conveyor belt 11b, 12b, a suction unit 11c, 12c, a floating air blowing mechanism 11d, 12d, a floating air shutter 11e, 12e, a separation air blowing mechanism 11f, 12f, a medium detection sensor 11g, 12g, and an end fence 11h, 12h. Note that since the first supply unit 11 and the second supply unit 12 can be configured in the same way, in FIG. 3, the reference number of the second supply unit 12 is written in parentheses after the reference number of the first supply unit 11. Similarly, in FIG. 3, the reference numbers of the sixth conveyor roller pair 26 and the second inlet passage detection sensor S21 are written in parentheses after the reference numbers of the first conveyor roller pair 21 and the first inlet passage detection sensor S11.

A plurality of media M are loaded on the loading trays 11a and 12a. Different types (sizes, materials, colors, etc.) of media M may be loaded on the loading tray 11a of the first supply unit 11 and the loading tray 12a of the second supply unit 12. In this case, when the type of medium M to be printed is changed, the supply unit that supplies the medium M is switched between the first supply unit 11 and the second supply unit 12. The loading trays 11a and 12a are raised and lowered by driving a loading tray lifting and lowering drive unit (not shown). As an example, when the number of media M loaded on the loading trays 11a and 12a decreases, the control unit (not shown) of the first supply unit 11 or the second supply unit 12 (or the control unit 31 shown in FIG. 2) controls the loading tray lifting and lowering drive unit to raise the loading trays 11a and 12a based on the amount of reflected light of light horizontally irradiated by the media detection sensors 11g and 12g described later to a predetermined loading surface height.

The conveyor belts 11b and 12b are, for example, endless belt-like and are stretched over two pulleys. The conveyor belts 11b and 12b are provided with a plurality of through holes for passing the suction air A1 sucked by the suction units 11c and 12c described later. The conveyor belts 11b and 12b rotate counterclockwise in FIG. 3 to pay out the media M that has been sucked in by the suction air A1 sucked by the suction units 11c and 12c, one by one. The conveyor belts 11b and 12b are an example of a payout unit that pays out the media M from the first supply unit 11 and the second supply unit 12, one by one. Note that, instead of the conveyor belts 11b and 12b, other conveyor members such as conveyor rollers may be used as the payout unit.

The suction units 11c and 12c suck suction air A1 by driving a suction source (e.g., a suction fan) not shown through multiple through holes provided in the conveyor belts 11b and 12b. As a result, the suction units 11c and 12c adsorb the uppermost medium M1 that is floating among the multiple media M loaded on the loading tables 11a and 12a to the conveyor belts 11b and 12b.

The floating air blowing mechanisms 11d, 12d blow out floating air A2, for example, by a blowing fan, to float at least the topmost medium M1 of the multiple media M stacked on the stacking tables 11a, 12a. The floating air blowing mechanisms 11d, 12d may blow out floating air A2 diagonally upward to float, for example, about 10 media M including the topmost medium M1. Note that FIG. 3 illustrates the floating air blowing mechanisms 11d, 12d positioned downstream (right side) in the transport direction of the media M, but it is also preferable to position floating air blowing mechanisms on both sides in the width direction (front-to-back direction) perpendicular to the transport direction of the media M.

The floating air shutters 11e and 12e are an example of a blocking part that blocks the blowing of floating air A2 by the floating air blowing mechanism 11d, and open and close between a closed position that blocks the blowing and an open position that does not block the blowing. This blocking part may be a control unit that stops the blowing of floating air A2 by the floating air blowing mechanisms 11d and 12d, but by using the floating air shutters 11e and 12e, the blowing of floating air A2 can be blocked instantly. The floating air shutters 11e and 12e may be capable of adjusting the volume of the floating air A2 at one or more positions between the closed position and the open position.

The separation air blowing mechanisms 11f and 12f blow out separation air A3, for example by a blowing fan, so as to separate the topmost medium M1 from the second medium M2 located below the topmost medium M1. Note that the separation air blowing mechanisms 11f and 12f, like the floating air blowing mechanisms 11d and 12d, may have a separation air shutter, which is an example of a blocking section, so as to be able to block all or part of the separation air A3. Also, FIG. 3 illustrates the separation air blowing mechanisms 11f and 12f arranged downstream (right side) in the transport direction of the medium M, but it is preferable that separation air blowing mechanisms are arranged on both sides of the width direction (front-to-back direction) of the medium M.

The media detection sensors 11g and 12g detect the media M loaded on the loading trays 11a and 12a. The media detection sensors 11g and 12g detect the presence or absence of media M at the detection height, for example, based on the reflected light of horizontally irradiated detection light. By the media detection sensors 11g and 12g detecting the presence or absence of media M, the control unit of the first supply unit 11 or the second supply unit 12 (not shown) (or the control unit 31 shown in FIG. 2) can detect the height of the topmost medium M1 loaded on the loading trays 11a and 12a. The media detection sensors 11g and 12g may also irradiate detection light toward the floating media M and detect the floating state of the media M (for example, the number of media M in the detectable range in the height direction) based on the amount of reflected light.

The end fences 11h and 12h regulate the position of the upstream end in the transport direction of the floated medium M. Although not shown, it is also preferable to provide a pair of side fences that regulate the position of the end in the width direction of the medium M loaded on the loading tables 11a and 12a.

As described above, the first supply unit 11 and the second supply unit 12 have floating air blowing mechanisms 11d, 12d, and blow out floating air A2 to float and supply the medium M, but the supply units may also supply the medium M without floating it.

In addition, although not shown, the first supply unit 11 and the second supply unit 12 may have a loading platform lifting drive unit such as a motor (an example of an actuator) that moves the loading platforms 11a, 12a up and down, and a payout drive unit such as a motor (an example of an actuator) that rotates a drive pulley, which is one of the two pulleys around which the conveyor belts 11b, 12b are stretched.

Returning to FIG. 1, the first individual transport path P1 is connected to the first supply unit 11. The second individual transport path P2 is connected to the second supply unit 12. The junction transport path P3 is a transport path where the first individual transport path P1 and the second individual transport path P2 join together, and extends to the registration roller pair 131 of the printing device 101. Note that the first individual transport path P1 and the second individual transport path P2 have different path lengths for the transport path of the medium M. For example, the path length of the second individual transport path P2 is less than half the path length of the first individual transport path P1.

The first individual transport path P1 is mostly located in the upper level 1a of the medium supply device 1, and the second individual transport path P2 is located in the lower level 1b of the medium supply device 1. The first individual transport path P1 merges with the second individual transport path P2 at the merging transport path P3 located in the lower level 1b.

Each of the first to ninth transport roller pairs 21 to 29 has a drive roller and a driven roller arranged opposite each other, and transports the medium M while nipping it.

The first to fifth transport roller pairs 21 to 25 transport the medium M in the first individual transport path P1 in the upper tier 1a of the medium supply device 1. The sixth and seventh transport roller pairs 26, 27 transport the medium M in the second individual transport path P2 in the lower tier 1b of the medium supply device 1. The eighth and ninth transport roller pairs 28, 29 transport the medium M in the merging transport path P3 in the lower tier 1b of the medium supply device 1. In addition, the receiving roller pair 132 of the printing device 101, which will be described later, transports the medium M in the merging transport path P3 of the printing device 101. The first to fifth transport roller pairs 21 to 25 and the sixth and seventh transport roller pairs 26, 27 are examples of multiple individual transport sections that transport the medium M in the first individual transport path P1 and the second individual transport path P2 (multiple individual transport paths). Additionally, the eighth and ninth conveying roller pairs 28, 29 and the receiving roller pair 132 are an example of a junction conveying section that conveys the medium M on the junction conveying path P3. The first individual conveying path P1, the second individual conveying path P2, and the junction conveying path P3 are an example of a conveying path connected to a supply section (the first supply section 11 or the second supply section 12), and the first to ninth conveying roller pairs 21-29 and the receiving roller pair 132 are an example of a conveying section that conveys the medium M on the conveying path.

The first to fourth transport drive units D1 to D4 are motors (an example of an actuator) that rotate the drive rollers of the first to ninth transport roller pairs 21 to 29. The first transport drive unit D1 rotates the drive rollers of the first and second transport roller pairs 21, 22. The second transport drive unit D2 rotates the drive rollers of the third to fifth transport roller pairs 23 to 25. The third transport drive unit D3 rotates the drive rollers of the sixth and seventh transport roller pairs 26, 27. The fourth transport drive unit D4 rotates the drive rollers of the eighth and ninth transport roller pairs 28, 29. The first and second transport drive units D1, D2 and the third transport drive unit D3 are examples of individual transport drive units that drive multiple individual transport units (the first to seventh transport roller pairs 21 to 27). The fourth transport drive unit D4 and the transport drive unit (not shown) that drives the receiving roller pair 132 are an example of a confluence transport drive unit that drives the confluence transport unit (the eighth and ninth transport roller pairs 28, 29 and the receiving roller pair 132). The first to fourth transport drive units D1 to D4 and the transport drive unit (not shown) that drives the receiving roller pair 132 are also an example of a transport drive unit that drives the transport unit (the first to ninth transport roller pairs 21 to 29 and the receiving roller pair 132). The transport speed of the medium M by the first to ninth transport roller pairs 21 to 29 is, for example, constant. However, the transport speed may be different between the first individual transport path P1, the second individual transport path P2, and the confluence transport path P3, or the transport speed may be different within at least one of the first individual transport path P1, the second individual transport path P2, and the confluence transport path P3.

The first entrance passage detection sensor S11, the first intermediate passage detection sensors S12 to S14, the first exit passage detection sensor S15, the second entrance passage detection sensor S21, the second intermediate passage detection sensors S22 and S23, and the second exit passage detection sensor S24 are, for example, reflective or transmissive photoelectric sensors that detect the passage of media M.

The first entrance passage detection sensor S11 is disposed adjacent to the first conveying roller pair 21 on the downstream side in the conveying direction of the first conveying roller pair 21. The first mid-way passage detection sensor S12 is disposed adjacent to the second conveying roller pair 22 on the downstream side in the conveying direction of the second conveying roller pair 22. The first mid-way passage detection sensor S13 is disposed adjacent to the third conveying roller pair 23 on the downstream side in the conveying direction of the third conveying roller pair 23. The first mid-way passage detection sensor S14 is disposed adjacent to the fourth conveying roller pair 24 on the downstream side in the conveying direction of the fourth conveying roller pair 24. The first exit passage detection sensor S15 is disposed adjacent to the fifth conveying roller pair 25 on the downstream side in the conveying direction of the fifth conveying roller pair 25.

The first entrance passage detection sensor S11 detects the passage of medium M, and the first exit passage detection sensor S15 detects the passage of medium M near the exit of the first individual transport path P1.

The second entrance passage detection sensor S21 is disposed adjacent to the sixth conveying roller pair 26 on the downstream side in the conveying direction of the sixth conveying roller pair 26. The second midway passage detection sensor S22 is disposed adjacent to the seventh conveying roller pair 27 on the downstream side in the conveying direction of the seventh conveying roller pair 27. The second midway passage detection sensor S23 is disposed adjacent to the eighth conveying roller pair 28 on the downstream side in the conveying direction of the eighth conveying roller pair 28. The second exit passage detection sensor S24 is disposed adjacent to the ninth conveying roller pair 29 on the downstream side in the conveying direction of the ninth conveying roller pair 29.

The second entrance passage detection sensor S21 detects the passage of medium M near the entrance of the second individual transport path P2, and the second exit passage detection sensor S24 detects the passage of medium M near the exit of the media supply device 1 on the merging transport path P3.

The first entrance passage detection sensor S11 and the second entrance passage detection sensor S21 are examples of entry detection sensors that detect that the medium M supplied from the supply unit (first supply unit 11 or second supply unit 12) has entered the transport path (first individual transport path P1 or second individual transport path P2). This entry detection sensor may be the first mid-way passage detection sensor S12 or the second mid-way passage detection sensor S22, etc., since there is no particular restriction on the detection position on the transport path (first individual transport path P1 or second individual transport path P2). However, since it is used to determine whether empty transport is occurring in the medium M, it is preferable that it is located near the first supply unit 11 or the second supply unit 12.

The first midway passage detection sensors S12 to S14, the first exit passage detection sensor S15, the second midway passage detection sensors S22 and S23, the second exit passage detection sensor S24, and the registration sensor S30 are examples of passage detection sensors that detect the passage of medium M downstream in the transport direction of medium M from the entry detection sensor (first entrance passage detection sensor S11 or second entrance passage detection sensor S21) and upstream in the transport direction from the intake transport section (registration roller pair 131).

The control unit 31 shown in FIG. 2 has a processor (e.g., CPU: Central Processing Unit) that functions as an arithmetic processing device that controls the operation of the entire medium supply device 1, and controls each part of the medium supply device 1. For example, the control unit 31 controls the first supply unit 11, the second supply unit 12, and the first to fourth transport drive units D1 to D4 based on a supply signal for the medium M that the interface unit 33 described later receives from the interface unit 153 (control unit 151) of the printing device 101. Note that the control of the first supply unit 11 and the second supply unit 12 may be performed by the control units arranged in the first supply unit 11 and the second supply unit 12, respectively, when the control unit receives the supply signal from the printing device 101. Also, when the medium supply device 1 is provided integrally with a supply destination device such as the printing device 101, the control unit of the supply destination device (e.g., the control unit 151 of the printing device 101 described later) may function as the control unit 31.

The storage unit 32 may include, for example, a ROM (Read Only Memory), which is a read-only semiconductor memory in which a specific control program is pre-recorded, or a RAM (Random Access Memory), which is a semiconductor memory that can be written and read at any time and is used as a working memory area as necessary when the processor executes various control programs. Note that in cases where the medium supply device 1 is provided integrally with a destination device such as the printing device 101, the storage unit of the destination device (for example, the storage unit 152 of the printing device 101 described below) may function as the storage unit 32.

The interface unit 33 exchanges various information with external devices such as the printing device 101. For example, the interface unit 33 receives information such as a medium M supply signal and the detection results of the registration sensor S30 from the interface unit 153 of the printing device 101, and the control unit 31 controls the operation of each part of the medium supply device 1 based on this information. The interface unit 33 also sends information such as a notification of retry mode 1 or 2, which will be described later, to the interface unit 153 of the printing device 101.

Next, we will explain the printing device 101.

As shown in Figures 1 and 2, the printing device 101 includes a printing unit 110, a suction conveying unit 120, a conveying unit 130, a registration sensor S30, a destination conveying path P11, a circulating inversion conveying path P12, an inversion unit 140, a control unit 151, a memory unit 152, and an interface unit 153. Note that in Figure 1, the junction conveying path P3 and the destination conveying path P11 are shown with solid lines, and the circulating inversion conveying path P12 is shown with dashed lines.

The printing unit 110 has, for example, a line-head type inkjet head (not shown) for each color used for printing. Note that the printing method of the printing unit 110 may be a printing method other than the inkjet printing method.

As shown in FIG. 1, the suction transport unit 120 is disposed to face the printing unit 110. The suction transport unit 120 transports the medium M by a transport belt while suctioning the medium M.

The transport unit 130 has a registration roller pair 131 that corrects skew of the medium M by being abutted against the medium M transported toward the printing unit 110, a receiving roller pair 132 that transports the medium M in the merging transport path P3 continuing from the medium supply device 1, and multiple transport roller pairs 133 that transport the medium M in the destination transport path P11 or the circulating inversion transport path P12. The registration roller pair 131, the receiving roller pair 132, and the multiple transport roller pairs 133 transport the medium M while nipping it.

The registration roller pair 131 is an example of an intake conveying section that takes in the medium M conveyed by the above-mentioned conveying section (the first to ninth conveying roller pairs 21 to 29 and the receiving roller pair 132) into, for example, the supply destination conveying path P11 of the printing device 101. The registration roller pair 131 is also an example of a reference arrival position in the merging conveying path P3, where, for example, the medium M arrives at a reference arrival time of a predetermined interval, and the medium M is taken in, for example, at a take-in time of a predetermined interval. The reference arrival time and take-in time may be a time with a range. The reference arrival time and take-in time may also be set for each medium M based on, for example, the size of the medium M, the printing time of the printing section 110 corresponding to the print content, the gap between the media M that are continuously conveyed, etc. The arrival of the medium M at the registration roller pair 131 later than the reference arrival time is a factor in determining whether a jam has occurred, and causes a delay in the printing start time by the printing section 110 and variations in the accuracy of skew correction. The reference arrival position may be any position other than the registration roller pair 131.

The registration sensor S30 is disposed near the registration roller pair 131 in the junction conveying path P3 upstream in the conveying direction of the registration roller pair 131. The registration sensor S30 is disposed in the junction conveying path P3 and is an example of an arrival detection sensor that detects the arrival time of the medium M. This arrival detection sensor may be the above-mentioned second exit passage detection sensor S24 disposed in the junction conveying path P3 of the medium supplying device 1. As described above, the medium supplying mechanism in this embodiment includes the medium supplying device 1, the configuration of the conveying path to the registration roller pair 131 of the printing device 101 (the receiving roller pair 132, the registration roller pair 131, the registration sensor S30, and the junction conveying path P3), and the control unit 151 of the printing device 101, so that the receiving roller pair 132 and the registration sensor S30 can be said to be part of the medium supplying mechanism.

The pair of registration rollers 131, which is an example of the reference arrival position described above, is not provided with a sensor to detect the medium M. Therefore, it is possible to determine whether the medium M has reached the pair of registration rollers 131 based on the detection result of the registration sensor S30.

The destination transport path P11 is connected to the junction transport path P3 continuing from the medium supply device 1, and extends downstream in the transport direction from the registration roller pair 131. In the printing system 100 shown in FIG. 1, if other printing devices or medium ejection devices are arranged downstream in the transport direction of the printing device 101, the destination transport path P11 is connected to the transport paths of these devices.

The circular inversion transport path P12 transports medium M when printing is to be performed on the opposite side of medium M that has been printed on one side by the printing unit 110.

The inversion unit 140 has an inversion path and a pair of switchback rollers that invert the front and back of the medium M transported to the circulatory inversion transport path P12.

The control unit 151 shown in FIG. 2 has a processor (e.g., a CPU) that functions as an arithmetic processing device that controls the operation of the entire printing device 101, and controls each part of the printing device 101. As will be described in detail later, the control unit 151 controls the pair of registration rollers 131 to delay the take-in time of the medium M based on a notification of retry mode 1 or 2 received from the control unit 31 of the medium supplying device 1. Therefore, it can be said that the control unit 31 of the medium supplying device 1 indirectly controls the pair of registration rollers 131 using the control unit 151 of the printing device 101.

The storage unit 152 has memories such as a ROM, which is a read-only semiconductor memory in which a specific control program is pre-recorded, and a RAM, which is a semiconductor memory that can be written and read at any time and is used as a working memory area as necessary when the processor executes various control programs.

The interface unit 153 exchanges various information with external devices such as the medium supply device 1 and a user terminal that transmits print data. For example, as described above, the interface unit 153 sends information such as a supply signal for the medium M and the detection results of the registration sensor S30 to the interface unit 33 of the medium supply device 1, and receives information such as a notification of retry mode 1 or 2 from the interface unit 33.

Next, we will provide an overview of the operation of the printing system 100, omitting points that overlap with the above explanation as appropriate.

First, the control unit 31 shown in FIG. 2 controls the first supply unit 11 and the second supply unit 12 to switch between the medium M of the first supply unit 11 and the medium M of the second supply unit 12 shown in FIG. 1, or to supply the medium M from only one of the first supply unit 11 or the second supply unit 12, based on a supply signal for the medium M received by the interface unit 33 from the printing device 101 (interface unit 153).

The control unit 31 controls the first to fifth transport roller pairs 21 to 25 using the first transport drive unit D1 and the second transport drive unit D2 to transport the medium M supplied from the first supply unit 11 along the first individual transport path P1. When the medium M is transported along the first individual transport path P1, its passage is detected by the first entrance passage detection sensor S11, the first intermediate passage detection sensors S12 to S14, and the first exit passage detection sensor S15.

The control unit 31 also controls the sixth and seventh transport roller pairs 26, 27 using the third transport drive unit D3 to transport the medium M supplied from the second supply unit 12 along the second individual transport path P2. When the medium M is transported along the second individual transport path P2, its passage is detected by the second entrance passage detection sensor S21 and the second mid-way passage detection sensor S22.

The control unit 31 then controls the eighth and ninth transport roller pairs 28, 29 using the fourth transport drive unit D4 to transport the medium M transported from the first individual transport path P1 or the second individual transport path P2 to the merging transport path P3. When the medium M is transported to the merging transport path P3, its passage is detected by the second midway passage detection sensor S23 and the second exit passage detection sensor S24.

As a result, the medium M is supplied to the junction transport path P3 of the printing device 101, which is connected to the junction transport path P3 of the medium supply device 1, its passage (arrival) is detected by the registration sensor S30, it is abutted against the registration roller pair 131 to correct the skew, and then printing is performed by the printing unit 110.

Next, the details of the medium M supply operation in this embodiment will be described with reference to FIG.

Figure 4 is a flowchart explaining the supply operation of medium M.

Note that each process in the flowchart shown in FIG. 4 begins when the control unit 31 of the medium supply device 1 shown in FIG. 2 receives a medium M supply signal from, for example, the control unit 151 of the printing device 101.

First, the control unit 31 of the media supply device 1 determines whether it has received a supply end instruction sent from the control unit 151 of the printing device 101 in response to the end of printing or interruption of printing (step S41).

When the control unit 31 receives a supply end instruction (step S41: YES), it stops the transport of the medium M by the first supply unit 11, the second supply unit 12, and the first to ninth transport roller pairs 21 to 29 (step S42), and ends the supply operation shown in FIG. 4.

When the control unit 31 does not receive a supply end instruction (step S41: NO) but receives a supply signal (step S43), it determines whether the medium M is to be transported (taken in) in retry mode 2 (described below) (step S44). If the medium M is to be transported in retry mode 2 (step S44: YES), the control unit 31 repeats the process from step S41 described above, since no new supply of medium M is to be performed.

If the medium M is not being transported in retry mode 2 (step S44: NO), the control unit 31 starts the transport belts 11b, 12b of the first supply unit 11 or the second supply unit 12 (step S45, for example, times t10, t13 in Figure 5).

The control unit 31 also updates the elapsed time T from the start of the conveyor belts 11b and 12b (step S46) and determines whether the medium M has passed through the entry detection sensor (the first entrance passage detection sensor S11 or the second entrance passage detection sensor S21) (step S47).

When the medium M passes the entry detection sensor (step S47: YES, for example, times t11 and t15 in FIG. 5), the control unit 31 determines whether the elapsed time T is later than the time T2, which is the end of the correction range (step S48). Here, the correction range is equal to or greater than T1 and equal to or less than T2 (T1≦T≦T2), which is the first range R1 shown in FIG. 5. Note that this first range R1 and the second range R2 described later are not limited to the elapsed time T from the start of the conveyor belts 11b and 12b, but may be a time range starting from other conditions, such as when control is performed to start the conveyor belts 11b and 12b, or when the conveyor belts 11b and 12b reach a predetermined rotation speed.

If the elapsed time T is equal to or less than T2 (step S48: NO), the control unit 31 determines whether the elapsed time T is earlier than the time T1, which is the start of the first range R1 (step S49).

When the control unit 31 determines that the elapsed time T is equal to or greater than the time T1 at the beginning of the first range R1 (step S49: NO), the first range R1 satisfies the relationship T1≦T≦T2 (for example, time t11 in FIG. 5), and corrects the transport speed of the medium M by controlling the first to fourth transport drive units D1 to D4 so that the arrival time of the medium M to the registration roller pair 131 approaches a constant value (step S50). The control unit 151 of the printing device 101 also controls the registration roller pair 131 (the registration drive unit that drives the registration roller pair 131) to take in the medium M at a predetermined take-in time, for example, time t12 shown in FIG. 5. The control unit 31 of the medium supplying device 1 then repeats the process from step S41 described above.

Here, the correction of the transport speed of the medium M will be explained with reference to Figures 8 and 9.

Figures 8 and 9 are diagrams showing the relationship between the conveying speed and elapsed time to explain the correction of the conveying speed. In Figures 8 and 9, the medium M supplied from the second supply unit 12 is used as an example.

8, the time (time t41a) when the medium M passes through the second entrance passage detection sensor S21 is delayed from the reference passing time (time t41), which is a theoretical value determined in advance, due to a large amount of slippage between the medium M and the conveyor belt 12b and a low conveyance rate. Therefore, in order to make up for the delay of the medium M and to bring the abutment time (arrival time) at which the medium M abuts against the pair of registration rollers 131 closer to a constant (reference abutment time (reference arrival time)), the control unit 31 determines the conveying speed v1 between the second entrance passage detection sensor S21 and the second exit passage detection sensor S24 (second individual conveying path P2 and merging conveying path P3) so that the conveying speed v1 is faster than the conveying speed v0 between the second exit passage detection sensor S24 and the registration sensor S30. Note that the thick line portion in FIG. 8 represents the case where the conveying speed is not corrected, as will be described later.

On the other hand, in the example of FIG. 9, the slippage between the medium M and the conveyor belt 12b is reduced and the conveying rate is increased, so that the passing time (time t41b) of the medium M through the second entrance passage detection sensor S21 is faster than the reference passing time (time t41), which is a predetermined theoretical value. In this case, in order to make the abutment time (arrival time) at which the medium M abuts against the pair of registration rollers 131 closer to a constant (reference abutment time (reference arrival time)), the control unit 31 determines the conveying speed v2 between the second entrance passage detection sensor S21 and the second exit passage detection sensor S24 (second individual conveying path P2 and merging conveying path P3) so that the conveying speed v2 is slower than the conveying speed v0 between the second exit passage detection sensor S24 and the registration sensor S30.

The deviation of the passing time (times t41a, t41b) of the second inlet passing detection sensor S21 of the above-mentioned media M from the reference passing time (time t41) is not limited to when the topmost media M, which is floated by the floating air and separated from the lower media M by the separation air, is adsorbed and transported by the transport belt 12b, but also occurs when the topmost media M and the lower media M are separated by a separation plate or the like, due to friction acting between the separation plate and the media M.

4, when the control unit 31 determines that the elapsed time T is earlier than the time T1 (step S49: YES), it can be said that the medium M has reached the entry detection sensor earlier than the first range R1, and therefore notifies the control unit 151 of the printing device 101 of a jam error (step S51). Then, the control unit 31 of the medium supplying device 1 repeats the process from the above-mentioned step S41.
For example, when the control unit 151 of the printing device 101 receives a jam error notification, it sends a supply end instruction to the control unit 31 to stop the supply of the medium M.

Returning to step S48 above, if it is determined that the elapsed time T is slower than T2 (step S48: YES), this is limited to the case where the elapsed time T is equal to or shorter than time T3, which is the end of the second range R2, after going through steps S54 to S56 described below before the medium M passes the entry detection sensor in step S47 above. Therefore, since the elapsed time T falls within the second range R2 that satisfies the relationship T2<T≦T3 (for example, time t15 in FIG. 5), the control unit 31 notifies the control unit 151 of the printing device 101 of retry mode 2 (step S52). In this case, the control unit 31 does not perform the speed correction of the medium M described above (step S53), and repeats the process from step S41 above.

Here, when the control unit 31 of the medium supply device 1 notifies the control unit 151 of the printing device 101 of retry mode 2, the control unit 31 delays the supply of the next medium M from the supply unit (for example, stops one supply as shown at time t17 in FIG. 5). As a result, the conveying speed is not corrected (corrected to increase the conveying speed), and the medium M is conveyed at the conveying speed v0 as shown by the thick solid line in FIG. 8, so that the passing time t42a of the second exit passage detection sensor S24 is delayed from the reference passing time t42, the arrival time t43a of the registration sensor S30 is delayed from the reference arrival time t43, and the impact time t44a (arrival time) of the registration roller pair 131 is delayed from the reference impact time t44. However, as shown in FIG. 11, the nth medium M, which is transported later than planned (dashed line), does not come into contact with the nth medium M when it abuts against the registration roller pair 131, for example, because the supply of the next n+1th medium M (next medium M to be transported) is delayed by, for example, one time, as described above.

In addition, when the control unit 31 of the medium supplying device 1 notifies the control unit 151 of the printing device 101 of retry mode 2, the control unit 151 of the printing device 101 controls the registration roller pair 131 to delay the take-in time of the medium M (for example, by stopping the take-in as shown at time t16 in FIG. 5). For example, the control unit 151 may control the registration roller pair 131 to take in the medium M whose take-in time has been delayed at the take-in time (for example, time 18 in FIG. 5) at which the next transported medium M was scheduled to be taken in.

When notifying the retry mode 2, the control unit 31 may block the blowing of the floating air A2 by the floating air shutters 11e and 12e shown in FIG. 3 (for example, time t15 in FIG. 5). As a result, as shown in FIG. 10A, the medium M on the stacking table 11a and 12a that has been floating due to the blowing of the floating air A2 by the floating air blowing mechanism 11d and 12d is dropped when the preceding medium M is detected by the entry detection sensor (the first inlet passage detection sensor S11 or the second inlet passage detection sensor S21) as shown in FIG. 10B. Therefore, so-called double feeding can be suppressed. When notifying the retry mode 2, if the floating air shutters 11e and 12e are already closed and the blowing of the floating air A2 is blocked as shown in FIG. 10B, the control unit 31 may not open the floating air shutters 11e and 12e until the next medium M is supplied.

When notifying retry mode 2, the control unit 31 may reschedule the allowable time for each sensor as shown in Figs. 12A to 12D. Note that Figs. 12A to 12D use the medium M supplied from the first supply unit 11 as an example, and explain the time in msec.

As shown in FIG. 12A, with respect to the elapsed time T from the start of the conveyor belt 11b, the theoretical passing time of the first inlet passage detection sensor S11 is 100, and the allowable passing time is 80 to 120. If the elapsed time T falls outside this allowable passing time, for example, a non-reaching jam, which is an error indicating that the medium M is not being conveyed normally, is notified to the control unit 151. Also, the allowable time for a retention jam of the first inlet passage detection sensor S11 is 380. If the elapsed time T exceeds this retention jam, a retention jam, which is an error indicating that the medium M is retained in the conveyor path, is notified to the control unit 151.

The theoretical passing time of the first midway passing detection sensor S12 (first midway passing detection sensor 1), which has a required time of 50 from the first entrance passing detection sensor S11, is 150, the allowable passing time is 135 to 165, and the allowable jam time is 435. The reason why the range of the allowable passing time is narrower than that of the first entrance passing detection sensor S11 is because when the above-mentioned conveying speed correction is performed, the arrival time of the registration roller pair 131 is made closer to a constant.

The required time from the first entrance passage detection sensor S11 is 100, the theoretical passing time of the first midway passage detection sensor S13 (first midway passage detection sensor 2) is 200, the allowable passing time is 190 to 210, and the allowable jam time is 490.

The theoretical passing time of the first midway passing detection sensor S14 (first midway passing detection sensor 3), whose required time from the first entrance passing detection sensor S11 is 150, is 250, the allowable passing time is 245 to 255, and the allowable jam time is 545.

The theoretical passing time of the first exit passage detection sensor S15, which has a required time of 200 from the first entrance passage detection sensor S11, is 300, the allowable passing time is only 300, and the allowable jam time is 600.

The theoretical passing time of the registration sensor S30, whose required time from the first entrance passing detection sensor S11 is 250, is 350, the allowable passing time is only 350, and the allowable jam time is 650.

As described above, when the elapsed time T is in the second range R2 that has passed the first range R1 (allowable passage time), the actual passing time of the first entrance passage detection sensor S11 will be, for example, 140, which exceeds the allowable passing time of 80 to 120 for the first entrance passage detection sensor S11. This means that the actual passing times of the other sensors are expected to also exceed the allowable passing times.

Therefore, as shown in FIG. 12B, the control unit 31 sets the predicted passing time of each sensor to, for example, the sum of the actual passing time (140) of the first entrance passing detection sensor S11 and the required time from the first entrance passing detection sensor S11.

The control unit 31 also updates the end of the permissible passage time for each sensor to a time later than the expected passage time, as shown in FIG. 12C. The control unit 31 also invalidates the permissible time for a jam or changes it to an appropriately long time.

Then, when the time to take in the medium M is determined (for example, time t18 in FIG. 5), the control unit 31 updates the allowable time for retention jam to match that time, as shown in FIG. 12D.

Returning to the flowchart of FIG. 4, if the medium M does not pass the entry detection sensor (step S47: NO), the control unit 31 determines whether the elapsed time T is later than the time T2, which is the end of the first range R1, in the same manner as in step S48 described above (step S54). If the elapsed time T is equal to or less than T2 (step S54: NO), the control unit 31 returns to step S46 described above.

If the elapsed time T is later than the time T2 which is the end of the first range R1 (step S54: YES), the control unit 31 stops the conveying belts 11b and 12b (step S55, for example, time t14 shown in Figure 5).

The control unit 31 also determines whether the elapsed time T is later than T3, which is the end of the second range R2 (extended range) (step S56). If the elapsed time T is equal to or less than T3 (step S56: NO), the control unit 31 returns to the above-mentioned step S46.

If the elapsed time T is longer than T3 (step S56: YES, for example, if the second range R2 starting from time t24 in FIG. 6 has elapsed), the control unit 31 notifies the control unit 151 of the printing device 101 of retry mode 1 (step S57), and repeats the process from step S41 described above.

Here, when the control unit 31 of the medium supplying device 1 notifies the control unit 151 of the printing device 101 of retry mode 1, the control unit 151 controls the pair of registration rollers 131 to stop taking in the medium M (for example, time t25 in FIG. 6). Meanwhile, the control unit 31 of the medium supplying device 1 starts the conveyor belts 11b, 12b of the supply unit (first supply unit 11 or second supply unit 12) to supply the next medium M as usual (for example, time t26 in FIG. 6, step S5 in FIG. 4). The control unit 151 also controls the pair of registration rollers 131 to take in the next medium M at a predetermined take-in time (for example, time t27 in FIG. 6).

In the present embodiment described above, the medium supply mechanism includes a supply unit (e.g., first supply unit 11 and second supply unit 12) that supplies medium M, a transport path (e.g., first individual transport path P1, second individual transport path P2, and merging transport path P3) connected to the supply unit, a transport unit (e.g., first to ninth transport roller pairs 21-29 and receiving roller pair 132) that transports medium M on the transport path, a transport drive unit (e.g., first to fourth transport drive units D1-D4 and the transport drive unit of transport unit 130) that drives the transport unit, an entry detection sensor (e.g., first inlet passage detection sensor S11 and second inlet passage detection sensor S21) that detects that medium M supplied from the supply unit has entered the transport path, an intake transport unit (e.g., registration roller pair 131) that takes in medium M transported by the transport unit, and a control unit (e.g., control units 31, 151) that controls the supply unit and the intake transport unit. This control unit controls the intake transport unit to take in the medium M (e.g., time t12 in FIG. 5) when the time when the entry of the medium M is detected by the entry detection sensor is within a predetermined first range R1 (e.g., time t11 in FIG. 5). Also, when the time when the entry of the medium M is detected by the entry detection sensor is within a second range R2 that is beyond the first range R1 (e.g., time t15 in FIG. 5), the control unit controls the supply unit to delay the supply of the next medium M to be transported, and controls the intake transport unit to delay the intake time of the medium M (e.g., from time t16 to time t18).

As shown in FIG. 7 (comparison example), even if the conveyor belts 11b and 12b are stopped when the medium M does not reach the entry detection sensor (entrance passage detection sensor) at a predetermined time (for example, time t34 at the end of the first range R1), the conveyor belts 11b and 12b may not stop immediately and the medium M may reach the entry detection sensor later than the predetermined time (for example, time t35). In this case, the supply of the medium M is treated as an error, and the supply of the medium M is stopped, or the intake of the medium M by the registration roller pair 131 (registration drive unit) is stopped (times t37 and t38). In contrast, in this embodiment, when the time when the entry of the medium M is detected by the entry detection sensor is the second range R2 that has passed the first range R1, the intake time of the medium M by the intake conveying unit and the supply of the next medium M to be conveyed are delayed, so that the medium M can be conveyed without the need to correct the conveying speed even if the time when the medium M is detected by the entry detection sensor is later than the reference passage time. This makes it possible to avoid the need to use complex configurations such as high-performance motors to increase the transport speed, and also prevents errors such as jams caused by the medium M being transported too late even when the transport speed is increased.

Therefore, according to this embodiment, the delayed medium M can be reliably transported with a simple configuration.

In addition, in this embodiment, when the time at which the entry of medium M is detected by the entry detection sensor is within the second range (e.g., time t15 in FIG. 5), the control unit controls the intake transport unit to intake medium M with a delayed intake time (e.g., time t16) at the intake time (e.g., time t18) at which the next medium M to be transported was scheduled to be taken in.

As a result, the transport of medium M can be continued by simply pausing the transport of medium M by the transport unit once (for example, time t16 in FIG. 5). Therefore, medium M can be transported with simple control.

In addition, in this embodiment, when the time at which the entry of medium M is detected by the entry detection sensor is within the first range R1, the control unit corrects the transport speed of medium M by controlling the transport drive unit so that the arrival time of medium M to the intake transport unit approaches a constant (for example, transport speed v1 in FIG. 8 and transport speed v2 in FIG. 9). Furthermore, when the time at which the entry of medium M is detected by the entry detection sensor is within the second range R2, the control unit does not correct the transport speed to make the arrival time of medium M to the intake transport unit approach a constant.

As a result, when the time at which medium M is detected by the entry detection sensor is within the first range R1, the time at which it reaches the intake transport section can be made closer to constant, thereby making it possible to avoid, for example, delays in the start time of printing by the printing section 110 and variations in the accuracy of skew correction. Also, when the time at which medium M is detected by the entry detection sensor is within the second range R2, the intake of medium M by the intake transport section is delayed (for example, a one-time rest period), so medium M can be transported with simple control that does not correct the transport speed (correction to increase the transport speed).

In this embodiment, the medium supply mechanism further includes a passage detection sensor (e.g., first midway passage detection sensor S12-S14, first exit passage detection sensor S15, second midway passage detection sensor S22, S23, second exit passage detection sensor S24, and registration sensor S30) that detects the passage of medium M downstream of the entry detection sensor in the transport direction of medium M and upstream of the intake transport section in the transport direction. When the time at which the entry of medium M is detected by the entry detection sensor is within the second range R2, the control unit reschedules the allowable time (e.g., the allowable passage time or the allowable jam time shown in Figures 12A-12D) for the time at which the passage of medium M is detected by the passage detection sensor.

This makes it possible to prevent errors such as jams caused by delayed transport of the medium M even if the transport speed of the medium M that is supplied late and whose time detected by the entry detection sensor is within the second range R2 is not corrected.

In this embodiment, the supply unit includes a loading platform 11a, 12a on which media M are loaded, a floating air blowing mechanism 11d, 12d that blows floating air A2 to float at least the topmost medium M1 of the multiple media M loaded on the loading platform 11a, 12a, and a blocking unit (e.g., floating air shutter 11e, 12e) that blocks the blowing of the floating air A2 by the floating air blowing mechanism 11d, 12d. When the time at which the entry of the medium M is detected by the entry detection sensor is within the second range R2, the control unit causes the blocking unit to block the blowing of the floating air A2 (e.g., time t15 in FIG. 5).

This prevents the medium M transported next to the delayed medium M from floating due to the blowing of floating air A2, resulting in double feeding of the medium M.

<Other embodiments>
In the above-described embodiment, the control unit 31, 151 controls the registration roller pair 131 (an example of an intake conveying unit) to delay the intake time of the registration roller pair 131, for example, to the intake time of the next medium M to be conveyed (for example, from time t16 to time t18) when the time at which the entry of the medium M is detected by the first entrance passage detection sensor S11 and the second entrance passage detection sensor S21 (an example of an entry detection sensor) is within the second range R2 which is beyond the first range R1 (for example, time t15 in Figure 5).

For example, medium M whose entry detection time of the second entrance passage detection sensor S21 was in the second range R has a delayed take-in time by the registration roller pair 131, so the transport speed is not corrected to increase, and the medium is transported at the same specified transport speed v0 as medium M that is transported normally without correction, as shown by the dashed line in FIG. 13. As a result, the passing time t42c of medium M through the second exit passage detection sensor S24 is delayed from the reference passing time t42, the arrival time t43c of the registration sensor S30 is delayed from the reference arrival time t43, and the impact time t44c (arrival time) of the registration roller pair 131 is delayed from the reference impact time t44.

However, even if the contact time t44c with the registration roller pair 131 is delayed in this way, if the take-in time of medium M is delayed to the take-in time of the next medium M to be transported, for example, the state in which medium M is contacted with the registration roller pair 131 continues until the take-in time. As a result, the accuracy of skew correction of medium M decreases.

Therefore, in this embodiment, when the entry detection time is within the second range R2, the transport drive unit (e.g., the fourth transport drive unit D4) is controlled to temporarily stop transport of the medium M (or slow down the transport speed of the medium M) to delay the time when the medium M reaches the registration roller pair 13. Note that in this embodiment, the configuration of the printing system 100 can be the same as in the above-mentioned embodiment, so only the differences from the above-mentioned embodiment will be described.

Figure 14 is a diagram showing the relationship between the transport speed and elapsed time to explain the stop of transport. In Figure 14, as in Figure 13, the example is explained using medium M supplied from the second supply unit 12.

First, when there is a lot of slippage between the medium M and the conveyor belt 12b and the conveying rate is low, and the passing time (time t41c) of the medium M through the second inlet passage detection sensor S21 is within the second range R2 described above (for example, time t15 in Figure 5), the passing time (time t41c) is delayed from the reference passing time (time t41), which is a theoretical value determined in advance.

The control unit 31 controls the third transport drive unit D3 to accelerate the transport speed of the medium M to a transport speed v0 after the medium M passes through the second entrance passage detection sensor S21, similar to the transport speed of the medium M transported normally, as indicated by the dashed line. The control unit 31 also temporarily stops the transport of the medium M after the leading edge of the medium M passes through the second exit passage detection sensor S24 and before it reaches the registration roller pair 131.

Furthermore, the control unit 31 controls the fourth transport drive unit D4 to return the transport speed of the medium M to the specified transport speed v0 before the medium M reaches the registration roller pair 131. The timing for returning the transport speed of the medium M stopped by the control unit 31 to the transport speed v0 in this manner may be controlled by controlling the fourth transport drive unit D4 and the transport drive unit of the transport unit 130 so that the medium M to be transported next reaches the registration roller pair 131 at the arrival time (reference abutment time t52) when the medium M was scheduled to reach the registration roller pair 131. In this case, the time when the medium M reaches the registration sensor S30 is also the same as the arrival time (reference arrival time t51) when the medium M to be transported next was scheduled to reach the registration sensor S30. However, even if the next medium M to be transported reaches the registration roller pair 131 earlier than the arrival time (reference arrival time t51) at which the medium M was scheduled to reach the registration sensor S30, the time during which the medium M remains in contact with the registration roller pair 131 can be significantly shortened by temporarily stopping the transport of the medium M or slowing down the transport speed of the medium M.

In the example shown in FIG. 14, the transport of medium M is temporarily stopped, but the time during which medium M remains in contact with the registration roller pair 131 can also be shortened by slowing down the transport speed of medium M so that the transport speed does not become zero.

In this embodiment, in order to temporarily stop the transport of medium M and delay the time at which medium M reaches the registration roller pair 131, it is advisable to reschedule the time by delaying the predicted passing time (390 msec) and the end of the permitted passing time (395 msec) in the table of the rescheduling of the allowable times for each sensor shown in FIG. 12D described above to the predicted passing time (705 msec) and the end of the permitted passing time (710 msec) shown in FIG. 15.

The receiving roller pair 132 shown in FIG. 1 nips the medium M that is relatively short in length in the transport direction, but does not nip the medium M that is relatively long in length in the transport direction. This is because the medium M can be transported by the eighth transport roller pair 28 and the ninth transport roller pair 29 and the registration roller pair 131 for the long medium M, and is therefore less susceptible to the influence of the difference in transport speed between the first to fourth transport drive units D1 to D4 on the medium supply device 1 side and the transport drive unit on the printing device 101 side. Therefore, when the long medium M is stopped or decelerated as described above, the leading edge of the long medium M may be located between the receiving roller pair 132 and the registration roller pair 131, but when the short medium M is stopped or decelerated as described above, it is preferable that the leading edge of the short medium M is located upstream of the receiving roller pair 132, and more preferably, the leading edge of the short medium M passes through the receiving roller pair 132 after the end of re-acceleration (after returning to the transport speed v0). Furthermore, when stopping or decelerating the medium M as described above, control is simplified by using only the fourth transport drive unit D4 without using the second transport drive unit D2 or the third transport drive unit D3 (particularly the second transport drive unit D2, which is arranged on the upper level 1a of the medium supply device 1, unlike the fourth transport drive unit D4).

In the other embodiments described above, the same effects can be obtained for the same matters as in the first embodiment described above, i.e., the medium M that is supplied with a delay can be reliably transported with a simple configuration.

In addition, in this embodiment, when the time at which the entry of medium M is detected by the entry detection sensor (e.g., the first entrance passage detection sensor S11 and the second entrance passage detection sensor S21) is within the second range R2, the control unit (e.g., the control unit 31, 151) controls the transport drive unit (e.g., the fourth transport drive unit D4) to temporarily stop the transport of medium M or slow down the transport speed of medium M to delay the time at which medium M reaches the intake transport unit (e.g., the registration roller pair 131).

This makes it possible to prevent the time that the medium M, whose intake time is delayed as described above because the entry detection time has fallen into the second range R2 (for example, from time t16 to time t18 in Figure 5), is struck by the intake transport section from becoming longer.

In addition, in this embodiment, the control unit temporarily stops the transport of medium M or slows down the transport speed of medium M, and then controls the transport drive unit to return the transport speed of medium M to the specified transport speed v0 before medium M reaches the intake transport unit.

As a result, for media M whose transport has been temporarily stopped or whose transport speed has been slowed down, transport control can be performed just before the media reaches the intake transport section, in the same way as for normal media M for which such control is not performed. Therefore, skew correction can be performed in the same way with the same control as for the normal media M.

In addition, in this embodiment, the control unit temporarily stops the transport of medium M or slows down the transport speed of medium M, and then controls the transport drive unit to make medium M arrive at the intake transport section at the arrival time (e.g., reference impact time 52 shown in FIG. 14) when the next medium M to be transported is scheduled to arrive at the intake transport section.

This allows the medium M to be taken in immediately by the intake transport section, thereby avoiding the medium M being pressed against the intake transport section for a long period of time.

The present invention is not limited to the above-described embodiment as it is, and the components can be modified and embodied without departing from the gist of the invention in the implementation stage. Various inventions can be formed by appropriately combining the multiple components disclosed in the above-described embodiment. For example, all the components shown in the embodiment may be appropriately combined. Of course, various modifications and applications are possible without departing from the spirit of the invention. The invention described in the claims of the original application of this application is described below.

[Appendix 1]
A supply unit that supplies a medium;
A conveying path connected to the supply unit;
a transport unit that transports the medium in the transport path;
A transport drive unit that drives the transport unit;
an entry detection sensor that detects that the medium supplied from the supply unit has entered the transport path;
an intake transport unit that takes in the medium transported by the transport unit;
A control unit that controls the supply unit and the intake conveying unit,
the control unit controls the intake transport unit to intake the medium when a time during which the intake detection sensor detects the intake of the medium is within a predetermined first range;
The control unit controls the supply unit to delay the supply of the next medium to be transported when the time at which the entry of the medium is detected by the entry detection sensor is within a second range that is greater than the first range, and controls the intake transport unit to delay the intake time of the medium.

[Appendix 2]
The control unit controls the intake transport unit to intake the medium with a delayed intake time to the scheduled intake time for the next medium to be transported when the time at which the entry of the medium is detected by the entry detection sensor is within the second range.

[Appendix 3]
when the time at which the entry of the medium is detected by the entry detection sensor is within the first range, the control unit corrects a transport speed of the medium by controlling the transport drive unit so as to make the arrival time of the medium to the take-in transport unit closer to a constant;
The medium supply mechanism described in Appendix 1 or 2, characterized in that when the time at which the entry of the medium is detected by the entry detection sensor is within the second range, the control unit does not correct the transport speed to make the arrival time of the medium at the intake transport unit closer to constant.

[Appendix 4]
a passage detection sensor that detects passage of the medium downstream of the entry detection sensor in the transport direction of the medium and upstream of the take-in transport unit in the transport direction;
The control unit reschedules the allowable time for the passage of the medium to be detected by the passage detection sensor when the time for the entry of the medium to be detected by the entry detection sensor is within the second range.

[Appendix 5]
the supply unit includes a loading platform on which the media are loaded, a floating air blowing mechanism that blows floating air to float at least the uppermost medium among the plurality of media loaded on the loading platform, and a blocking unit that blocks the blowing of the floating air by the floating air blowing mechanism,
A medium supply mechanism as described in any one of appendix 1 to 4, characterized in that the control unit causes the blocking unit to block the blowing of the floating air when the time during which the intrusion of the medium is detected by the intrusion detection sensor is within the second range.

[Appendix 6]
The medium supply mechanism described in Appendix 1 or 2, characterized in that when the time at which the entry of the medium is detected by the entry detection sensor is within the second range, the control unit controls the transport drive unit to temporarily stop transport of the medium or slow down the transport speed of the medium to delay the time at which the medium reaches the intake transport unit.

[Appendix 7]
The medium supply mechanism described in Appendix 6, characterized in that the control unit controls the transport drive unit to temporarily stop transport of the medium or slow down the transport speed of the medium, and then return the transport speed of the medium to a specified transport speed before the medium reaches the input transport unit.

[Appendix 8]
The control unit controls the transport drive unit to temporarily stop transport of the medium or slow down the transport speed of the medium, and then causes the medium to arrive at the intake transport unit at the arrival time when the next transported medium was scheduled to arrive at the intake transport unit.

1 medium supply device 1a upper stage 1b lower stage 11 first supply section 11a loading platform 11b conveyor belt 11c suction section 11d floating air blowing mechanism 11e floating air shutter 11f separation air blowing mechanism 11g medium detection sensor 11h end fence 12 second supply section 12a loading platform 12b conveyor belt 12c suction section 12d floating air blowing mechanism 12e floating air shutter 12f separation air blowing mechanism 12g medium detection sensor 12h end fence 21-29 first to ninth conveyor roller pairs 31 control section 32 memory section 33 interface section 100 printing system 101 printing device 110 printing section 120 suction conveyor section 130 conveyor section 131 registration roller pair 132 Receiving roller pair 133, conveying roller pair 140, reversing section 151, control section 152, memory section 153, interface section A1, suction air A2, floating air A3, separation air D1 to D4, first to fourth conveying drive sections M, medium P1, first individual conveying path P2, second individual conveying path P3, merging conveying path P11, supply destination conveying path P12, circulating reverse conveying path R1, first range R2, second range S11, first inlet passage detection sensor S12, first midway passage detection sensor 1
S13 First midway passage detection sensor 2
S14 First midway passage detection sensor 3
S15: First exit passage detection sensor S21: Second entrance passage detection sensor S22: Second midway passage detection sensor 1
S23 Second midway passage detection sensor 2
S24: Second exit passage detection sensor S30: Registration sensor

Claims (7)

A supply unit that supplies a medium;
A conveying path connected to the supply unit;
a transport unit that transports the medium in the transport path;
A transport drive unit that drives the transport unit;
An entry detection sensor that detects that the medium supplied from the supply unit has entered the transport path.
With
an intake transport unit that takes in the medium transported by the transport unit;
A control unit that controls the supply unit and the intake conveying unit,
the control unit controls the intake transport unit to intake the medium when a time during which the intake detection sensor detects the intake of the medium is within a predetermined first range;
the control unit controls the supply unit to delay the supply of the next medium to be transported when the time at which the entry of the medium is detected by the entry detection sensor is within a second range that is greater than the first range, and controls the take-in transport unit to delay a time at which the medium is taken in;
The control unit controls the intake transport unit to intake the medium with a delayed intake time to the scheduled intake time for the next medium to be transported when the time at which the intake of the medium is detected by the intake detection sensor is within the second range. A supply unit that supplies a medium;
A conveying path connected to the supply unit;
a transport unit that transports the medium in the transport path;
A transport drive unit that drives the transport unit;
An entry detection sensor that detects that the medium supplied from the supply unit has entered the transport path.
With Nsa,
an intake transport unit that takes in the medium transported by the transport unit;
A control unit that controls the supply unit and the intake conveying unit,
the control unit controls the intake transport unit to intake the medium when a time during which the intake detection sensor detects the intake of the medium is within a predetermined first range;
the control unit controls the supply unit to delay the supply of the next medium to be transported when the time at which the entry of the medium is detected by the entry detection sensor is within a second range that is greater than the first range, and controls the take-in transport unit to delay a time at which the medium is taken in;
when the time at which the entry of the medium is detected by the entry detection sensor is within the first range, the control unit corrects a transport speed of the medium by controlling the transport drive unit so as to make the arrival time of the medium to the take-in transport unit closer to a constant;
A medium supply mechanism characterized in that, when the time at which the entry of the medium is detected by the entry detection sensor is within the second range, the control unit does not correct the transport speed to make the arrival time of the medium at the intake transport unit closer to constant. A supply unit that supplies a medium;
A conveying path connected to the supply unit;
a transport unit that transports the medium in the transport path;
A transport drive unit that drives the transport unit;
An entry detection sensor that detects that the medium supplied from the supply unit has entered the transport path.
With Nsa,
an intake transport unit that takes in the medium transported by the transport unit;
A control unit that controls the supply unit and the intake conveying unit,
the control unit controls the intake transport unit to intake the medium when a time during which the intake detection sensor detects the intake of the medium is within a predetermined first range;
the control unit controls the supply unit to delay the supply of the next medium to be transported when the time at which the entry of the medium is detected by the entry detection sensor is within a second range that is greater than the first range, and controls the take-in transport unit to delay a time at which the medium is taken in;
a passage detection sensor that detects passage of the medium downstream of the entry detection sensor in the transport direction of the medium and upstream of the take-in transport unit in the transport direction;
The control unit reschedules the allowable time for the passage of the medium to be detected by the passage detection sensor when the time for the entry of the medium to be detected by the entry detection sensor is within the second range. A supply unit that supplies a medium;
A conveying path connected to the supply unit;
a transport unit that transports the medium in the transport path;
A transport drive unit that drives the transport unit;
An entry detection sensor that detects that the medium supplied from the supply unit has entered the transport path.
With Nsa,
an intake transport unit that takes in the medium transported by the transport unit;
A control unit that controls the supply unit and the intake conveying unit,
the control unit controls the intake transport unit to intake the medium when a time during which the intake detection sensor detects the intake of the medium is within a predetermined first range;
the control unit controls the supply unit to delay the supply of the next medium to be transported when the time at which the entry of the medium is detected by the entry detection sensor is within a second range that is greater than the first range, and controls the take-in transport unit to delay a time at which the medium is taken in;
the supply unit includes a loading platform on which the media are loaded, a floating air blowing mechanism that blows floating air to float at least the uppermost medium among the plurality of media loaded on the loading platform, and a blocking unit that blocks the blowing of the floating air by the floating air blowing mechanism,
The control unit controls the blocking unit to block the blowing of the floating air when the time during which the intrusion of the medium is detected by the intrusion detection sensor is within the second range. A supply unit that supplies a medium;
A conveying path connected to the supply unit;
a transport unit that transports the medium in the transport path;
A transport drive unit that drives the transport unit;
An entry detection sensor that detects that the medium supplied from the supply unit has entered the transport path.
With
an intake transport unit that takes in the medium transported by the transport unit;
A control unit that controls the supply unit and the intake conveying unit,
the control unit controls the intake transport unit to intake the medium when a time during which the intake detection sensor detects the intake of the medium is within a predetermined first range;
the control unit controls the supply unit to delay the supply of the next medium to be transported when the time at which the entry of the medium is detected by the entry detection sensor is within a second range that is greater than the first range, and controls the take-in transport unit to delay a time at which the medium is taken in;
The control unit controls the transport drive unit to temporarily stop transport of the medium or slow down the transport speed of the medium when the time at which the entry of the medium is detected by the entry detection sensor is within the second range, thereby delaying the time at which the medium reaches the intake transport unit. The medium supply mechanism of claim 5, characterized in that the control unit controls the transport drive unit to temporarily stop transport of the medium or slow down the transport speed of the medium, and then return the transport speed of the medium to a specified transport speed before the medium reaches the input transport unit. The medium supply mechanism of claim 5 or 6, characterized in that the control unit temporarily stops transport of the medium or slows down the transport speed of the medium, and then controls the transport drive unit so that the medium arrives at the intake transport section at the arrival time when the next transported medium is scheduled to arrive at the intake transport section.

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