Recording device tape and recording device

Abstract

The present invention provides a belt of a recording device and a recording device. A belt suitable for detecting the lateral swing amount of the belt and the reference position of one belt cycle is realized with a simple structure. The belt of the recording device has a plurality of marks for detecting the position of the belt in the conveying direction of the belt. The plurality of marks respectively have: a first specific part, the size of which in the conveying direction varies depending on the position in the cross direction intersecting with the conveying direction; and a second specific part, the size of which in the conveying direction is fixed regardless of the position in the cross direction. The plurality of marks include a reference mark whose size in the conveying direction of the second specific part is different from that of the other marks.

Description

Technical Field

[0001] The present invention relates to a belt used in a recording device such as an inkjet printer or a copier, and a recording device equipped with the belt. Background Art

[0002] In a recording device such as an inkjet printer, an endless conveyor belt is provided for conveying paper to a position opposite to a recording head. The conveyor belt is stretched and stretched by at least two rollers. When the conveyor belt oscillates laterally, the lateral oscillation can be corrected by tilting any one of the rollers according to the amount of lateral oscillation. For example, Patent Document 1 discloses a technique for correcting the lateral oscillation of a conveyor belt.

[0003] Prior art literature

[0004] Patent Document 1: Japanese Patent Publication No. 2006-264934

[0005] However, in an inkjet printer, it is sometimes desirable to detect a reference position of a conveyor belt. For example, when it is desirable to place paper at a predetermined position on the conveyor belt, if the reference position of a conveyor belt can be detected, the paper can be placed at the predetermined position on the conveyor belt by feeding the paper to the conveyor belt after a predetermined period of time has passed since the detection of the reference position.

[0006] Considering the correction of the lateral swing of the conveyor belt and the placement of the paper to a predetermined position on the conveyor belt, it is desirable to realize a conveyor belt suitable for detecting the lateral swing amount and the reference position of the conveyor belt. However, if a conveyor belt with a complex structure is required for performing these two detections, the manufacturing cost of the conveyor belt increases, which is not preferred. Therefore, it is desirable to realize a conveyor belt suitable for detecting the lateral swing amount and the reference position with a simple structure. However, such a conveyor belt has not yet appeared.

[0007] In addition, for example, the intermediate transfer belt of a color copier sometimes needs to detect the lateral swing amount and the reference position. Therefore, it is desired to realize a belt suitable for lateral swing amount detection and reference position detection that can also be applied to the intermediate transfer belt with a simple structure. Summary of the invention

[0008] In view of the above problems, an object of the present invention is to provide a recording device tape having a simple structure and being suitable for detecting the lateral vibration amount of the belt and the reference position of one belt revolution, and a recording device using the tape.

[0009] In order to achieve the above object, the present invention provides a belt of a recording device, which has a plurality of marks for detecting the position of the belt in the conveying direction of the belt. The plurality of marks respectively include: a first specific part, the size of which in the conveying direction varies depending on the position of a cross direction intersecting the conveying direction; and a second specific part, the size of which in the conveying direction is fixed regardless of the position of the cross direction. The plurality of marks include a reference mark, and the size of the second specific part of the reference mark in the conveying direction is different from that of other marks.

[0010] According to the above configuration, a belt suitable for detecting the lateral swing amount of the belt and detecting the reference position of one belt revolution can be realized with a simple configuration. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is an explanatory diagram showing a schematic structure of a printer as an inkjet recording device according to one embodiment of the present invention.

[0012] Figure 2 It is a top view of a recording unit included in the above-mentioned printer.

[0013] Figure 3 This is an explanatory diagram schematically showing the peripheral structure of a paper conveyance path from a paper feed cassette of the above-mentioned printer via a first conveyance unit to a second conveyance unit.

[0014] Figure 4 This is a block diagram showing the hardware configuration of the main parts of the above-mentioned printer.

[0015] Figure 5 This is an explanatory diagram showing an example of input signals and output signals to and from the mask circuit included in the above-mentioned printer.

[0016] Figure 6 It is a plan view showing a configuration example of a first conveyor belt included in the first conveyor unit.

[0017] Figure 7 It is a schematic representation of the use Figure 6 An example of a pattern of an opening portion group for flushing action when the first conveyor belt is moved, and an explanatory diagram of paper arranged on the first conveyor belt corresponding to the above-mentioned pattern.

[0018] Figure 8 It is an explanatory diagram schematically showing another example of the above-mentioned mode and paper arranged on the above-mentioned first conveyor belt corresponding to the above-mentioned mode.

[0019] Fig. 9 It is an explanatory diagram schematically showing still another example of the above-mentioned mode and paper arranged on the above-mentioned first conveyor belt corresponding to the above-mentioned mode.

[0020] Fig.10 It is an explanatory diagram schematically showing still another example of the above-mentioned mode and paper arranged on the above-mentioned first conveyor belt corresponding to the above-mentioned mode.

[0021] Fig.11 It is a top view showing a configuration example of a reference mark provided on the first conveyor belt.

[0022] Fig.12 It is a top view showing another configuration example of the above-mentioned reference mark.

[0023] Fig.13 It is a top view showing a configuration example of a normal mark provided on the above-mentioned first conveyor belt.

[0024] Fig.14 It is a top view showing another configuration example of the above-mentioned normal mark.

[0025] Fig.15 It is an explanatory diagram schematically showing a detection signal obtained when the belt sensor reads the above-mentioned reference mark, an output signal from the above-mentioned shielding circuit, and a lateral swing amount signal.

[0026] Fig.16 It is an explanatory diagram schematically showing a detection signal obtained when the belt sensor reads the normal mark, an output signal from the mask circuit, and a lateral swing amount signal.

[0027] Fig.17 It is an explanatory diagram schematically showing a lateral vibration amount signal obtained when the belt sensor reads the normal mark at the reference position.

[0028] Fig.18 It is an explanatory diagram schematically showing a lateral runout amount signal obtained when the belt sensor reads the normal mark at a position shifted from the reference position.

[0029] Fig.19 This is an explanatory diagram schematically showing a lateral runout amount signal obtained when the belt sensor reads the normal mark at another position shifted from the reference position.

[0030] Fig. 20 It is a plan view showing another configuration example of the first conveyor belt.

[0031] Fig.21 It is a top view showing a configuration example of another reference mark. DETAILED DESCRIPTION

[0032] [1. Structure of inkjet recording device]

[0033] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Figure 11 is an explanatory diagram showing a schematic structure of a printer 100 as an inkjet recording device according to an embodiment of the present invention. The printer 100 includes a paper cassette 2 as a paper storage unit. The paper cassette 2 is disposed at the lower portion of the printer body 1. The paper cassette 2 contains paper P as an example of a recording medium.

[0034] Downstream in the paper feeding direction of the paper feeding cassette 2, that is, Figure 1 A paper feeding device 3 is arranged on the upper right side of the paper feeding box 2. Through the paper feeding device 3, the paper P is Figure 1 The sheets are separated one by one and sent to the upper right of the paper feed box 2.

[0035] The printer 100 has a first paper feed path 4a therein. The first paper feed path 4a is located to the upper right of the paper feed cassette 2 in the paper feed direction. The paper P fed from the paper feed cassette 2 is fed vertically upward along the side of the printer body 1 through the first paper feed path 4a.

[0036] A registration roller pair 13 is provided at the downstream end of the first paper feeding path 4a in the paper feeding direction. In addition, the first conveying unit 5 and the recording unit 9 are arranged near the downstream of the registration roller pair 13 in the paper feeding direction. The paper P fed from the paper feed cassette 2 passes through the first paper feeding path 4a and reaches the registration roller pair 13. The registration roller pair 13 corrects the deviation of the paper P, estimates the timing of the ink ejection operation performed by the recording unit 9, and feeds the paper P to the first conveying unit 5.

[0037] The paper P conveyed to the first conveying unit 5 passes through the first conveying belt 8 (see Figure 2 ) is transported to a position opposite to the recording unit 9 (particularly the recording heads 17a to 17c described later). By ejecting ink from the recording unit 9 to the paper P, an image is recorded on the paper P. At this time, the ejection of ink in the recording unit 9 is controlled by the control unit 111 inside the printer 100. The control unit 111 is composed of, for example, a CPU (Central Processing Unit).

[0038] In the paper feeding direction, downstream of the first feeding unit 5 ( Figure 1 The second transport unit 12 is disposed on the left side of the recording unit 9. The paper P on which the image is recorded by the recording unit 9 is transported to the second transport unit 12. The ink ejected onto the surface of the paper P is dried while passing through the second transport unit 12.

[0039] A decurling unit 14 is provided downstream of the second conveying unit 12 in the paper conveying direction and near the left side of the printer body 1. The paper P dried with ink by the second conveying unit 12 is conveyed to the decurling unit 14, and curl generated in the paper P is corrected.

[0040] In the paper feeding direction, downstream of the decurling section 14 ( Figure 1The second paper feed path 4b is provided above the printer 100. When the paper P that has passed through the decurling unit 14 is not subjected to double-sided recording, it is discharged to a paper discharge tray 15 provided on the left side of the printer 100 through the second paper feed path 4b.

[0041] A reversing conveying path 16 for double-sided recording is provided at the upper part of the printer body 1 and above the recording unit 9 and the second conveying unit 12. In the case of double-sided recording, the paper P which has been recorded on one side (first side) of the paper P and has passed through the second conveying unit 12 and the decurling unit 14 is conveyed to the reversing conveying path 16 through the second paper conveying path 4b.

[0042] Next, in order to record on the other side (second side) of the paper P, the conveying direction of the paper P conveyed to the reversing conveying path 16 is switched. Then, the paper P is conveyed to the right side through the upper part of the printer body 1, passes through the registration roller pair 13, and is conveyed to the first conveying unit 5 again with the second side facing upward. In the first conveying unit 5, the paper P is conveyed to a position opposite to the recording unit 9, and an image is recorded on the second side by ink ejection from the recording unit 9. The paper P after double-sided recording is discharged to the paper discharge tray 15 through the second conveying unit 12, the decurling unit 14, and the second paper conveying path 4b in sequence.

[0043] In addition, a maintenance unit 19 and a cap unit 20 are arranged below the second conveying unit 12. The maintenance unit 19 moves horizontally to the bottom of the recording unit 9 when performing cleaning, wipes off the ink squeezed out from the ink ejection port of the recording head, and recovers the wiped off ink. In addition, cleaning refers to the action of forcibly squeezing out the ink from the ink ejection port of the recording head in order to discharge the thickened ink, foreign matter, and bubbles in the ink ejection port. The cap unit 20 moves horizontally to the bottom of the recording unit 9 when capping the ink ejection surface of the recording head, and then moves upward to be installed on the lower surface of the recording head.

[0044] Figure 2 1 is a top view of the recording unit 9. The recording unit 9 includes a head housing 10 and line print heads 11Y, 11M, 11C, and 11K. The line print heads 11Y to 11K are held in the head housing 10 at a predetermined height (e.g., 1 mm) relative to the conveying surface of the endless first conveyor belt 8, which is stretched over a driving roller 6a, a driven roller 6b, and another tension roller 7 (see FIG. Figure 3 In addition, the line print heads 11Y to 11K are arranged in order from downstream to upstream in the traveling direction of the first conveyor belt 8 .

[0045] The line print heads 11Y to 11K each have a plurality of (three in this case) recording heads 17a to 17c. The recording heads 17a to 17c are arranged in a staggered manner along the paper width direction (arrow BB' direction) that is orthogonal to the paper feeding direction (arrow A direction). The recording heads 17a to 17c have a plurality of ink ejection ports 18 (nozzles). The ink ejection ports 18 are arranged at equal intervals in the width direction of the recording heads 17a to 17c, that is, in the paper width direction (arrow BB' direction). The ink ejection ports 18 of the recording heads 17a to 17c eject the respective color inks of yellow (Y), magenta (M), cyan (C), and black (K) onto the paper P transported by the first conveyor belt 8.

[0046] Figure 3 The peripheral structure of the conveying path of the paper P from the paper supply cassette 2 to the second conveying unit 12 via the first conveying unit 5 is schematically shown. The tension roller 7 includes a tension roller 7a located upstream and a tension roller 7b located downstream. The tension roller 7a, the tension roller 7b, the driven roller 6b, and the driving roller 6a are arranged in sequence along the traveling direction (circumferential rotation direction) of the first conveyor belt 8.

[0047] The printer 100 includes ink receiving portions 31Y, 31M, 31C, and 31K on the inner peripheral surface side of the first conveyor belt 8. The ink receiving portions 31Y to 31K receive ink ejected from the recording heads 17a to 17c and passing through the openings 80 (see the opening group 82 to be described later) of the first conveyor belt 8 when the recording heads 17a to 17c perform the flushing operation. Figure 6 ) and recovers the ink. Therefore, the ink receiving parts 31Y to 31K are arranged at positions opposite to the recording heads 17a to 17c of the line print heads 11Y to 11K across the first conveyor belt 8. In addition, the ink recovered by the ink receiving parts 31Y to 31K is conveyed to a waste ink box and discarded, for example, but it can also be reused without being discarded.

[0048] Here, the flushing operation refers to ejecting ink at a timing different from the timing that contributes to image formation (image recording) on ​​the paper P in order to reduce or prevent clogging of the ink ejection port 18 due to drying of the ink. The flushing operation in the recording heads 17 a to 17 c is controlled by the control unit 111 .

[0049] The second conveying unit 12 is composed of a second conveying belt 12a and a dryer 12b. The second conveying belt 12a is stretched by two rollers, a driving roller 12c and a driven roller 12d. The paper P conveyed by the first conveying unit 5 and having an image recorded thereon by ink ejected by the recording unit 9 is conveyed by the second conveying belt 12a, and is dried by the dryer 12b during conveyance and conveyed to the decurling unit 14.

[0050] Figure 41 is a block diagram showing the hardware configuration of the main part of the printer 100. The printer 100 includes a registration sensor 21, a first paper sensor 22, a second paper sensor 23, belt sensors 24 and 25, and a lateral swing correction mechanism 30 in addition to the above configuration.

[0051] The alignment sensor 21 detects the paper P fed from the paper feed cassette 2 to the registration roller pair 13 by the paper feed device 3. The control unit 111 can control the timing of starting the rotation of the registration roller pair 13 based on the detection result of the alignment sensor 21. For example, the control unit 111 can control the timing of feeding the paper P after the skew (oblique movement) correction performed by the registration roller pair 13 to the first conveyor belt 8 based on the detection result of the alignment sensor 21.

[0052] The first paper sensor 22 is a line sensor that detects the position in the width direction of the paper P conveyed from the registration roller pair 13 to the first conveyor belt 8. The control unit 111 can record an image on the paper P by ejecting ink from the ink ejection outlets 18 corresponding to the width of the paper P among the ink ejection outlets 18 of the recording heads 17a to 17c of the line print heads 11Y to 11K based on the detection result of the first paper sensor 22.

[0053] The second paper sensor 23 is a detection sensor that detects the passage of the paper P supplied to the first conveyor belt 8 by the registration roller pair 13 as the recording medium supply unit. That is, the second paper sensor 23 detects the position of the paper P supplied by the first conveyor belt 8 in the conveying direction. The second paper sensor 23 is located upstream of the recording unit 9 and downstream of the first paper sensor 22 in the paper supply direction. The control unit 111 can control the timing of ejecting ink to the paper P that has passed through the first conveyor belt 8 and reached the position opposite to the line print heads 11Y to 11K (recording heads 17a to 17c) based on the detection result of the second paper sensor 23.

[0054] The belt sensors 24 and 25 detect a mark 90 (see Figure 6 ) is a transmissive or reflective optical sensor. The belt sensor 24 is located downstream of the recording section 9 and upstream of the driving roller 6a in the paper feeding direction (the traveling direction of the first conveyor belt 8). The belt sensor 25 is located between the driven roller 6b and the tension roller 7b that tension the first conveyor belt 8. The driven roller 6b is located upstream of the recording section 9 in the traveling direction of the first conveyor belt 8. In addition, the belt sensor 24 can also have the same function as the second paper sensor 23. The control section 111 can control the registration roller pair 13 based on the detection result of the belt sensor 24 or the belt sensor 25 to supply paper P to the first conveyor belt 8 at a specified timing. In addition, an example of the supply control of paper P will be described later.

[0055] Furthermore, by detecting the position of the paper using a plurality of sensors (eg, the second paper sensor 23 and the belt sensor 24 ) and detecting the mark 90 using a plurality of sensors (eg, the belt sensors 24 and 25 ), error correction of the detected position and detection of abnormality can also be performed.

[0056] The first paper sensor 22 and the second paper sensor 23 may also be transmissive or reflective optical sensors. In addition, the tape sensors 24 and 25 may also be CIS sensors (Contact Image Sensor). Figure 3 As shown in the figure, the belt sensor 25 is located at a position opposite to the inner peripheral surface of the first conveyor belt 8, but it can also be located at a position opposite to the outer peripheral surface of the first conveyor belt 8, similar to the belt sensor 24. In addition, the installation position of the belt sensor 25 is not limited to between the driven roller 6b and the tension roller 7b. For example, the installation position of the belt sensor 25 can also be between the tension roller 7a and the tension roller 7b, and can also be between the driving roller 6a and the tension roller 7a.

[0057] The lateral swing correction mechanism 30 corrects the lateral swing of the first conveyor belt 8 by tilting the rotation axis of the roller (e.g., the tension roller 7b) that tensions the first conveyor belt 8. The specific driving of the lateral swing correction mechanism 30 is controlled by the control unit 111. The lateral swing correction mechanism 30 is composed of, for example, a bearing portion that supports the above-mentioned rotation axis and a moving mechanism (including a motor, a cam, etc.) that moves the bearing portion in a direction intersecting the above-mentioned rotation axis.

[0058] In addition, the printer 100 further includes an operation panel 27, a storage unit 28, and a communication unit 29. The operation panel 27 is an operation unit for receiving various setting inputs from the user. For example, the user can operate the operation panel 27 to input information such as the size of the paper P placed in the paper feed cassette 2, that is, the size of the paper P conveyed by the first conveyor belt 8, the number of prints, etc.

[0059] The storage unit 28 is a memory that stores the operation program of the control unit 111 and various information, and is composed of ROM (Read Only Memory), RAM (Random Access Memory), non-volatile memory, etc. The information set by the operation panel 27 (for example, the information on the size of the paper P) is stored in the storage unit 28.

[0060] The communication unit 29 is a communication interface for transmitting and receiving information with the outside (for example, a personal computer (PC)). For example, when a user operates the PC to send a print command together with image data to the printer 100, the image data and the print command are input to the printer 100 via the communication unit 29. In the printer 100, the control unit 111 controls the recording heads 17a to 17c based on the image data to eject ink, and an image can be recorded on the paper P.

[0061] The printer 100 also includes a control board 110. The control board 110 includes a control unit 111, a mask circuit 112, a reference position calculation unit 113, and a lateral swing amount calculation unit 114. The control unit 111, the mask circuit 112, the reference position calculation unit 113, and the lateral swing amount calculation unit 114 are composed of the same CPU, but may be composed of different CPUs.

[0062] The control unit 111 is a controller that controls the operation of each unit of the printer 100. For example, the control unit 111 controls the ejection of ink by the recording heads 17a to 17c and the supply of the paper P to the first conveyor belt 8 by the registration roller pair 13.

[0063] The mask circuit 112 is, for example, a processing circuit that extracts a signal of a predetermined period or longer from the detection signals of the plurality of marks 90 output by the tape sensor 25 and outputs it as a valid pulse. Figure 5 When the detection signal shown is input from the tape sensor 25 to the masking circuit 112, the masking circuit 112 masks the high-level signal and outputs the low-level signal from the rising edge of the input signal until the predetermined period Tc (sec) has passed, and releases the masking at the time when the predetermined period Tc is reached, and outputs the signal of the level after the above time. Among the output signals from the masking circuit 112, the falling edge signal of the effective pulse extracted is the reference signal of one tape cycle.

[0064] The reference position calculation unit 113 obtains the reference position of one cycle of the first conveyor belt 8 based on the signal output from the mask circuit 112. The specific method of obtaining the reference position will be described later. Alternatively, the reference position calculation unit 113 may obtain the reference position of one cycle of the first conveyor belt 8 based on the detection signals of the plurality of marks 90 directly output from the belt sensor 25.

[0065] The lateral swing amount calculation unit 114 obtains the lateral swing amount (offset) of the first conveyor belt 8 based on, for example, the detection result of the plurality of marks 90 by the belt sensor 25. The control unit 111 controls the lateral swing correction mechanism 30 to correct the lateral swing of the first conveyor belt 8 based on the lateral swing amount obtained by the lateral swing amount calculation unit 114.

[0066] [2. Details of the first conveyor belt]

[0067] (2-1. One Configuration Example of the First Conveyor Belt)

[0068] Next, the first conveyor belt 8 of the first conveyor unit 5 will be described in detail. Figure 6 1 is a top view showing a configuration example of the first conveyor belt 8. In this embodiment, a negative pressure suction method is adopted in which the paper P is sucked onto the first conveyor belt 8 by negative pressure suction and conveyed. Therefore, numerous suction holes 8a are provided on the first conveyor belt 8, and the suction holes 8a allow suction air generated by negative pressure suction to pass through.

[0069] In addition, an opening group 82 is also provided on the first conveyor belt 8. The opening group 82 is a collection of openings 80 through which the ink ejected from each nozzle (ink ejection port 18) of the recording heads 17a to 17c passes during the flushing action. The opening area of ​​one opening 80 is larger than the opening area of ​​one suction hole 8a. The first conveyor belt 8 has a plurality of opening groups 82 in one cycle in the conveying direction (direction A) of the paper P, and in this embodiment, there are six opening groups 82. In addition, one cycle refers to the period during which the first conveyor belt 8 rotates one circle. In addition, when distinguishing each opening group 82 from each other, the six opening groups 82 from the downstream in the direction A are referred to as opening groups 82A to 82F. The above-mentioned suction hole 8a is located between the opening groups 82 and the opening groups 82 adjacent in the direction A. That is, on the first conveyor belt 8, no suction hole 8a is formed around the opening 80 of the opening group 82.

[0070] The opening group 82 is not fixed in the A direction in one cycle of the first conveyor belt 8. That is, in the A direction, the intervals between adjacent opening groups 82 are not fixed but vary (there are at least two types of such intervals). In this case, the maximum interval between two adjacent opening groups 82 in the A direction (for example, Figure 6 The interval between the opening group 82A and the opening group 82B is longer than the length in the A direction of the paper P of the minimum printable size (for example, A4 size (horizontally)) when it is placed on the first conveyor belt 8.

[0071] The above-mentioned opening portion group 82 has an opening portion row 81. The opening portion row 81 is composed of a plurality of opening portions 80 arranged in the tape width direction (paper width direction, BB' direction) perpendicular to the A direction. One opening portion group 82 has at least one row of opening portion rows 81 in the A direction, and in the present embodiment, has two rows of opening portion rows 81. In addition, when the two rows of opening portion rows 81 are distinguished from each other, one is referred to as the opening portion row 81a, and the other is referred to as the opening portion row 81b.

[0072] In one opening portion group 82, the openings 80 of any one opening portion row 81 (for example, the opening portion row 81a) are located at positions offset from the openings 80 of other opening portion rows 81 (for example, the opening portion row 81b) in the BB' direction, and are located at positions overlapping with a portion of the openings 80 of other opening portion rows 81 (for example, the opening portion row 81b) when viewed from the A direction. In addition, in each opening portion row 81, a plurality of openings 80 are located at equal intervals in the BB' direction.

[0073] As described above, one opening group 82 is formed by arranging a plurality of opening columns 81 in the A direction, and the width of the opening group 82 in the BB' direction is greater than the width of the recording heads 17a to 17c in the BB' direction. Therefore, the opening group 82 completely covers the ink ejection area in the BB' direction of the recording heads 17a to 17c, and the ink ejected from all the ink ejection ports 18 of the recording heads 17a to 17c passes through any opening 80 of the opening group 82 during the flushing operation.

[0074] (2-2. Pattern of the opening group used for flushing operation)

[0075] In the present embodiment, the paper P is conveyed using the first conveyor belt 8, and based on image data sent from the outside (e.g., a PC), the control unit 111 drives the recording heads 17a to 17c to eject ink onto the paper P, thereby recording an image on the paper P. At this time, by causing the recording heads 17a to 17c to perform a flushing operation (paper feed interval flushing operation) between the conveyed paper P, clogging of the ink ejection port 18 is reduced or prevented.

[0076] In this embodiment, the control unit 111 determines the pattern (combination) of the A direction of the plurality of opening groups 82 used for the flushing operation according to the size of the paper P used in one cycle of the first conveyor belt 8. In addition, the control unit 111 can identify the size of the paper P used based on the information stored in the storage unit 28 (for example, the size information of the paper P input through the operation panel 27a).

[0077] Figure 7 to Figure 10 1 and 2 show examples of patterns of the opening group 82 for flushing operations for different sizes of paper P. For example, when the paper P used is A4 size (horizontal) or letter size (horizontal), the control unit 111 selects Figure 7 That is, the control unit 111 is configured to control the opening group 82 as shown. Figure 6 The opening groups 82A, 82C, and 82F are selected from the six opening groups 82 shown as the opening groups 82 for the flushing operation. When the paper P used is A4 size (vertical) or letter size (vertical), as shown in FIG. Figure 8As shown, the control unit 111 selects the opening group 82A and 82D from the six opening groups 82 as the opening group 82 for the flushing operation. When the paper P used is A3 size, B4 size or standard size (all in vertical orientation), as shown in FIG. Fig. 9 As shown in FIG. 1 , the control unit 111 selects the opening group 82A, 82B, and 82E from the six opening groups 82 as the opening group 82 for the flushing operation. When the paper P used is 13 inches by 19.2 inches in size, as shown in FIG. Fig.10 As shown, the control unit 111 selects the opening groups 82A and 82D as the opening groups 82 for flushing operation from the six opening groups 82. In each of the drawings, for convenience, the openings 80 belonging to the opening group 82 of the above-mentioned mode are indicated by black.

[0078] Furthermore, the control unit 111 controls the recording heads 17a to 17c to perform a flushing operation at a timing when the opening group 82 positioned in a certain pattern faces the recording heads 17a to 17c by the movement of the first conveyor belt 8. Here, the movement speed (paper conveying speed) of the first conveyor belt 8, the intervals between the opening groups 82A to 82E, and the positions of the recording heads 17a to 17c relative to the first conveyor belt 8 are all known. Therefore, if the belt sensor 24 or the belt sensor 25 detects that a mark 90 (for example, a reference mark 90a described later) that serves as a reference passes by the movement of the first conveyor belt 8, it can be known how many seconds after the detection time the opening group 82A to 82E passes the position facing the recording heads 17a to 17c. Therefore, the control unit 111 can control the recording heads 17a to 17c to perform a flushing operation at a timing when the opening group 82 positioned in the above-mentioned certain pattern faces the recording heads 17a to 17c based on the detection result of the belt sensor 24 or the belt sensor 25.

[0079] Furthermore, the control unit 111 controls the supply of the paper P to the first conveyor belt 8 so that the paper P is offset from the opening portion groups 82 positioned in the determined pattern in the direction A. That is, the control unit 111 supplies the paper P between the plurality of opening portion groups 82 arranged in the above-described pattern in the direction A on the first conveyor belt 8 through the registration roller pair 13.

[0080] For example, when the paper P used is A4 size (horizontal) or letter size (horizontal), Figure 7 As shown, the control unit 111 controls the alignment roller pair 13 to supply paper P to the first conveyor belt 8 at a specified supply timing, so that two sheets of paper P are arranged on the first conveyor belt 8 between the opening section group 82A and the opening section group 82C, two sheets of paper P are arranged between the opening section group 82C and the opening section group 82F, and one sheet of paper (not shown) is arranged between the opening section group 82F and the opening section group 82A (of the next cycle).

[0081] When the paper P used is A4 size (vertical) or letter size (vertical), Figure 8 As shown, the control unit 111 controls the alignment roller pair 13 to supply paper P to the first conveyor belt 8 at a specified supply timing, so that two sheets of paper P are arranged on the first conveyor belt 8 between the opening group 82A and the opening group 82D, and two sheets of paper P are arranged between the opening group 82D and the opening group 82A (of the next cycle).

[0082] When the paper P used is A3 size, B4 size or standard size (all in portrait orientation), Fig. 9 As shown, the control unit 111 controls the alignment roller pair 13 to supply paper P to the first conveyor belt 8 at a specified supply timing, so that a piece of paper P is arranged on the first conveyor belt 8 between the opening section group 82A and the opening section group 82B, a piece of paper P is arranged between the opening section group 82B and the opening section group 82E, and a piece of paper (not shown) is arranged between the opening section group 82E and the opening section group 82A (of the next cycle).

[0083] In the case where the paper P used is 13 inches × 19.2 inches in size, Fig.10 As shown, the control unit 111 controls the alignment roller pair 13 to supply paper P to the first conveyor belt 8 at a specified supply timing, so that a piece of paper P is arranged on the first conveyor belt 8 between the opening group 82A and the opening group 82D, and a piece of paper P is arranged between the opening group 82D and the opening group 82A (of the next cycle).

[0084] That is, Figure 7 to Figure 10 As shown, the pattern of the opening group 82 used for the flushing action is determined according to the size of the paper P used, thereby determining the placement pattern of the paper P located at a position offset from the opening group 82 in the A direction.

[0085] (2-3. About Marking for Position Detection)

[0086] As described above, in order to supply the paper P to the first conveyor belt 8 and place it in a manner that does not overlap with the opening section group 82, for example, it is necessary to detect (determine) the position of the opening section group 82 (for example, the opening section group 82A) that serves as a reference in the belt conveying direction by the belt sensor 25, and determine the timing of supplying the paper P to the first conveyor belt 8 based on the detection result, and supply the paper P from the registration roller pair 13 to the first conveyor belt 8 at the above supply timing. At this time, in order to detect the position of the opening section group 82 that serves as a reference in the belt conveying direction, it is necessary to detect the reference position of the first conveyor belt 8 in a predetermined positional relationship with the opening section group (for example, the opening section group 82A) that serves as the reference in the belt conveying direction. In addition, in order to correct the lateral swing of the first conveyor belt 8 in the belt width direction (BB' direction), it is necessary to detect the lateral swing amount (displacement amount) of the first conveyor belt 8 in the BB' direction.

[0087] Therefore, if Figure 6 to Figure 10 As shown, the first conveyor belt 8 of this embodiment has a plurality of position detection marks 90 at substantially equal intervals in the conveying direction (direction A) at one end portion in the belt width direction (direction BB').

[0088] In addition, for the convenience of the following description, among the multiple marks 90 provided in the A direction, the mark 90 for detecting the reference position of one cycle of the first conveyor belt 8 is also referred to as a reference mark 90a, and the other marks 90 are also referred to as normal marks 90b. In addition, as an example, the number of the reference mark 90a is one, and the rest are all normal marks 90b. In addition, the total number of the marks 90 is the total of the reference mark 90a and the normal mark 90b, which is three or more, for example, five, but is not limited to this number.

[0089] <Benchmark>

[0090] An example of composition

[0091] Fig.11 1 is a top view showing an example of the construction of the reference mark 90a. The reference mark 90a is composed of a first specific portion 91 and a second specific portion 92. On the first conveyor belt 8, the first specific portion 91 and the second specific portion 92 are located side by side in the A direction. More specifically, the second specific portion 92 is located downstream of the first specific portion 91 in the A direction.

[0092] 《First specific part》

[0093] The first specific portion 91 is composed of a first portion 91a and a separation area 91b. The outer shape of the first portion 91a is a parallelogram in a top view (viewed from a direction perpendicular to the belt plane of the first conveyor belt 8), and the parallelogram has two sides that are located parallel to the A direction and opposite to each other in the BB' direction, and the other two sides that are inclined at an angle θ relative to the A direction in the belt plane. In addition, the angle θ can be an angle other than 90°, and can be an acute angle or an obtuse angle. The dimension (width) of the first portion 91a in the A direction is, for example, Lz (mm). Such a first portion 91a is composed of a hole 91a1 that penetrates the first conveyor belt 8 in the thickness direction.

[0094] The first portion 91a may be a shape other than a parallelogram. For example, the first portion 91a may be a rhombus having two sides parallel to the A direction and opposite to each other in the BB' direction and two other sides inclined at an angle θ with respect to the A direction.

[0095] The separation area 91b is composed of a partial area of ​​the first conveyor belt 8. More specifically, the separation area 91b is a belt area between the first portion 91a and the second portion 92a of the second specific portion 92 described later in the A direction. Due to the existence of this separation area 91b, the first portion 91a and the second portion 92a are located at positions separated in the A direction. As described later, the outer shape of the second portion 92a, when viewed from above, is a rectangle or a square whose two sides intersecting the A direction are perpendicular to the A direction. Therefore, the outer shape of the separation area 91b, which is sandwiched by the second portion 92a and the first portion 91a in the A direction, is measured from the belt end in the BB' direction toward the inner side of the belt (in the BB' direction) by the dimension in the A direction when viewed from above. Fig.11 The shape of the trapezoid is formed by the elongated shape from bottom to top.

[0096] As described above, the first portion 91a is a parallelogram shape in a plan view, and the separation area 91b is a trapezoid shape in a plan view, so the first specific portion 91 formed by splicing the first portion 91a and the separation area 91b in the A direction is formed by a trapezoidal shape in which the dimension in the A direction becomes longer from the belt end in the BB' direction toward the inner side of the belt in a plan view. That is, the first specific portion 91 can be considered to be a region in which the dimension in the A direction is different depending on the position of the intersecting direction (for example, the BB' direction) intersecting the A direction. In addition, the above-mentioned intersecting direction can also be considered to be a direction that forms an angle θ with the A direction.

[0097] 《Second specific part》

[0098] The second specific portion 92 is composed of a second portion 92a. The second portion 92a is located on the first conveyor belt 8 at a position parallel to the first portion 91a of the first specific portion 91 described above in the A direction across the separation area 91b. The outer shape of the second portion 92a is a rectangle in a plan view, and the rectangle has two sides that are located parallel to the A direction and opposite to each other in the BB' direction, and two sides that are located perpendicular to the A direction in the belt plane, but it can also be a square. Therefore, the dimension of the second specific portion 92 composed of the second portion 92a in the A direction is fixed regardless of the position in the BB' direction. Such a second portion 92a is composed of a hole 92a1 that penetrates the first conveyor belt 8 in the thickness direction, similar to the first portion 91a.

[0099] Another example of composition

[0100] Fig.129 is a top view showing another configuration example of the reference mark 90a. As shown in the figure, the first portion 91a included in the first specific portion 91 of the reference mark 90a and the second portion 92a constituting the second specific portion may also be respectively constituted by reflection members 91a2, 92a2 having a surface reflectivity different from that of the first conveyor belt 8. The reflection members 91a2, 92a2 may be constituted by, for example, a sealant, a coating, etc. In addition, although not shown in the figure, one of the first portion 91a and the second portion 92a of the reference mark 90a may be constituted by a hole, and the other may be constituted by a reflection member.

[0101] <General mark>

[0102] Fig.13 90b is a top view showing an example of the configuration of the general mark 90b. The general mark 90b has the same configuration as the reference mark 90a except that the dimension of the second portion 92a constituting the second specific portion 92 in the A direction is different from that of the reference mark 90a. That is, when the dimension of the second portion 92a in the A direction included in the reference mark 90a is La (mm) and the dimension of the second portion 92a in the A direction included in the general mark 90b is Lb (mm), La≠Lb, and in particular, La>Lb. Alternatively, La may be <Lb。

[0103] In addition, at the same position in the BB' direction, the dimensions of the first specific portion 91 in the A direction are equal to each other (for example, both are L (mm)) in both the reference mark 90a and the normal mark 90b. In addition, the dimension Lb in the A direction of the normal mark 90b is the same as the dimension Lz (mm) in the A direction of the first portion 91a of the first specific portion 91, but they may be different.

[0104] Fig.14 9 is a top view showing another configuration example of the normal mark 90b. Similar to the reference mark 90a, the first portion 91a included in the first specific portion 91 of the normal mark 90b and the second portion 92a constituting the second specific portion may be respectively constituted by reflection members 91a2 and 92a2 having a surface reflectivity different from that of the first conveyor belt 8. In addition, although not shown in the figure, one of the first portion 91a and the second portion 92a of the normal mark 90b may be constituted by a hole, and the other may be constituted by a reflection member.

[0105] <Relationship between tags>

[0106] In the reference mark 90a and the normal mark 90b, the structures of the first specific part 91 and the second specific part 92 are as described above. In the reference mark 90a and the normal mark 90b, the first specific part 91 has the same shape, so in the reference mark 90a and the normal mark 90b, the maximum dimension in the A direction of the first specific part 91 is the same. Therefore, when the relationship of the dimension in the A direction of the second specific part 92 is, for example, La > Lb (refer to Fig.11 , Fig.13 ), the maximum dimension Lmax1 (mm) in the A direction of the reference mark 90a is longer than the maximum dimension Lmax2 (mm) in the A direction of the normal mark 90b. In the present embodiment, on the first conveyor belt 8, each mark 90 is located at positions arranged side by side in the A direction at intervals longer than the maximum dimension Lmax1 in the A direction of the reference mark 90a (refer to Figure 6 ).

[0107] In addition, when La < Lb, on the first conveyor belt 8, each mark 90 is located at positions arranged side by side in the A direction at intervals longer than the maximum dimension Lmax2 in the A direction of the normal mark 90b. That is, on the first conveyor belt 8, each mark 90 is located at positions arranged side by side in the A direction at intervals longer than the maximum dimension of the mark 90 with the largest dimension in the A direction among the reference mark 90a and the normal mark 90b.

[0108] (2-4. Detection method of reference position and detection method of lateral swing amount)

[0109] Next, each method for detecting the reference position around the belt and the lateral swing amount in the belt width direction using the first conveyor belt 8 having the above-described mark 90 will be described. In addition, here, the first part 91a included in the mark is constituted by the hole 91a1, the second part 92a is constituted by the hole 92a1, and the belt sensor 25 is constituted by a transmissive optical sensor. In addition, when the first part 91a is constituted by the reflection member 91a2 and the second part 92a is constituted by the reflection member 92a2, in this case, by using a reflective optical sensor as the belt sensor 25, in the same manner as in the case of using a transmissive optical sensor, the reference position around the belt and the lateral swing amount in the belt width direction can be detected.

[0110] Fig.15 Schematically shows the detection signal (output signal) of the belt sensor 25, the output signal from the shielding circuit 112, and the lateral swing amount signal obtained by the lateral swing amount calculation unit 114 when the belt sensor 25 reads an arbitrary position in the BB' direction of the reference mark 90a as the first conveyor belt 8 travels in the A direction. As the detection signal of the belt sensor 25, the detection time (time t 11 at the end X11 ) rises, and at the upstream end X of the second portion 92a 12 The detection time (time t 12 ) descends, and at the downstream end X of the first portion 91a (hole 91a1). 13 The detection time (time t 13 ) rises, at the upstream end X of the first portion 91a 14 The detection time (time t 14 ) falling signal.

[0111] If the above detection signal is input to the shielding circuit 112, the shielding circuit 112 will 11 The low-level signal is output until the predetermined period Tc has passed. At the time when the predetermined period Tc has passed (time t 1c ) directly outputs the level of the above detection signal. Fig.15 In the example, at time t 11 ~t 12 The period is longer than the prescribed period Tc, so from time t 11 After a predetermined period Tc has passed, the mask circuit 112 outputs a high-level signal until time t 12 In addition, at time t 13 ~t 14 The period is shorter than the prescribed period Tc, so the time t in the above detection signal 13 ~t 14 The high level of is completely shielded. As a result, at time t 12 Thereafter, a low-level signal is output from the mask circuit 112 .

[0112] In contrast, Fig.16 The following diagram schematically shows the detection signal (output signal) of the belt sensor 25 obtained when the belt sensor 25 reads an arbitrary position in the BB' direction (the same reading position as the reference mark 90a in the BB' direction) of the normal mark 90b as the first conveyor belt 8 travels in the A direction, the output signal from the masking circuit 112, and the lateral swing amount signal obtained by the lateral swing amount calculation unit 114. As the detection signal of the belt sensor 25, the end X at the downstream of the second portion 92a (hole 92a1) is obtained. 21 The detection time (time t 21 ) rises, and at the upstream end X of the second portion 92a 22 The detection time (time t 22 ) descends, and at the downstream end X of the first portion 91a (hole 91a1). 23 The detection time (time t 23 ) rises, at the upstream end X of the first portion 91a 24 The detection time (time t24 ) falling signal.

[0113] If the detection signal is input to the shielding circuit 112, the shielding circuit 112 will be 21 The low-level signal is output until the predetermined period Tc has passed. At the time when the predetermined period Tc has passed (time t 2c ) directly outputs the level of the above detection signal. Fig.16 In the example, at time t 21 ~t 22 The period and time t 23 ~t 24 Both of the periods are shorter than the specified period Tc, so the high level of the above detection signal is completely shielded. 21 ~t 24 , a low-level signal is output from the shielding circuit 112.

[0114] like Fig.15 and Fig.16 As shown, the output signal of the mask circuit 112 is different when the belt sensor 25 reads the reference mark 90a and when the belt sensor 25 reads the normal mark 90b. Therefore, the reference position calculation unit 113 determines whether there is a signal that becomes a high level (especially a falling edge) based on the output signal of the mask circuit 112, thereby being able to determine whether the belt sensor 25 has read the reference mark 90a, that is, whether the reference mark 90a has passed the detection position of the belt sensor 25 by the movement of the first conveyor belt 8. As a result, the reference position of one cycle of the first conveyor belt 8 can be detected at the same position of the reference mark 90a.

[0115] In this way, if the reference position of one cycle of the first conveyor belt 8 can be detected, the travel speed of the first conveyor belt 8 can be fixed, and after a predetermined time has passed from the detection time of the reference position, it is detected that a predetermined opening section group 82 (for example, the opening section group 82A) passes through a predetermined position. Therefore, the control unit 111 can control the registration roller pair 13 to supply the paper P to the first conveyor belt 8 so as to be at a predetermined position relative to the predetermined opening section group 82. Figure 7 The paper P is placed in the positional relationship shown in the figure.

[0116] In addition, the reference position calculation unit 113 can directly (without the shielding circuit 112) obtain the reference position of one cycle of the first conveyor belt 8 based on the detection signal of the belt sensor 25. For example, the reference position calculation unit 113 obtains the end X downstream in the A direction from the second specific portion 92 (second portion 92a) of the reference mark 90a. 11 The detection time to the upstream end X 12 The elapsed time Tref (=t 12 -t 11), when the elapsed time Tref is greater than a preset threshold value Tth (sec), the belt sensor 25 determines that the reference mark 90a is read, thereby being able to determine the reference position of one circle of the first conveyor belt 8.

[0117] On the other hand, regarding the lateral swing amount of the first conveyor belt 8, the lateral swing amount calculation unit 114 can obtain a lateral swing amount signal based on the output signal of the belt sensor 25, and calculate the lateral swing amount based on the lateral swing amount signal. This will be described in more detail below.

[0118] For example, the lateral swing amount signal obtained when the belt sensor 25 reads the normal mark 90b is a signal obtained by measuring the lateral swing amount from the upstream end X of the second specific portion 92 (second portion 92a) of the normal mark 90b. 22 The detection time (time t 22 ) to the upstream end X of the first specific portion 91 (first portion 91a) 24 The detection time (time t 24 ) during the period TB(=t 24 -t 22 ) as a high level and the rest of the time as a low level signal.

[0119] Here, Fig.17 The figure schematically shows the lateral swing amount signal obtained when the belt sensor 25 reads the normal mark 90b at the reference position in the BB' direction. The reference position corresponds to the position read by the belt sensor 25 when no lateral swing in the BB' direction occurs on the first conveyor belt 8. Fig.17 The horizontal swing amount signal will become a high level period, that is, from the end X 22 The detection time (time t 22 ) to the end X 24 The detection time (time t 24 ) period is set to TB0.

[0120] Fig.18 Schematically shows the inner side of the first conveyor belt 8 in the BB' direction (in Fig.17 The belt sensor 25 is at the belt end side (in the arrow B' side) closer to the BB' direction than the reference position. Fig.17 The lateral swing amount signal is obtained when the normal mark 90b is read from the arrow B side. In the above lateral swing amount signal, the period of high level, that is, from the end X 22 The detection time (time t 22 ) to the end X 24 The detection time (time t 24) is set as TB1. It can be seen that the dimension of the first specific portion 91 in the A direction changes according to the position in the BB' direction, being shorter at the end of the belt and longer at the inner side of the belt, so TB1 <TB0。

[0121] Fig.19 The following diagram schematically shows a lateral swing amount signal obtained when the belt sensor 25 reads the normal mark 90b on the inner side of the belt in the BB' direction relative to the reference position due to the lateral swing of the first conveyor belt 8 toward the belt end in the BB' direction. 22 The detection time (time t 22 ) to the end X 24 The detection time (time t 24 ) is set as TB2. Because the size of the first specific portion 91 in the A direction is determined by the position in the BB' direction and Fig.18 The changes are similar, so it can be seen that TB2>TB0.

[0122] Thus, when the first conveyor belt 8 oscillates in the BB' direction, the length of the period TB during which the lateral oscillation amount signal is at a high level changes according to the lateral oscillation amount. Therefore, the lateral oscillation amount calculation unit 114 can calculate the lateral oscillation amount of the first conveyor belt 8 in the BB' direction based on the length of the period TB.

[0123] The lateral swing amount calculation unit 114 can also calculate the lateral swing amount based on the lateral swing amount signal obtained when the tape sensor 25 reads the reference mark 90a. The lateral swing amount signal obtained when the tape sensor 25 reads the reference mark 90a is a signal obtained by measuring the lateral swing amount from the upstream end X of the second specific portion 92 (second portion 92a) of the reference mark 90a. 12 The detection time (time t 12 ) to the upstream end X of the first specific portion 91 (first portion 91a) 14 The detection time (time t 14 ) during the period TA(=t 14 -t 12 ) as a high level and the rest of the time as a low level signal (refer to Fig.15 ). When the first conveyor belt 8 oscillates in the BB' direction, the length of the period TA during which the lateral oscillation amount signal becomes high varies according to the lateral oscillation amount. This is also the case with the reference mark 90a as with the normal mark 90b. The size of the first specific portion 91 in the A direction (from the end X to the end X) can be known. 12 To end X 14 The distance) is shorter on the belt end side in the BB' direction and longer on the inner side of the belt.

[0124] Therefore, the lateral swing amount calculation unit 114 can obtain the lateral swing amount in the BB' direction of the first conveyor belt 8 based on the length of the period TA. That is, although the dimension of the second specific portion 92 in the A direction is different between the reference mark 90a and the normal mark 90b, the lateral swing amount can be detected regardless of the position of the normal mark 90b or the position of the reference mark 90a, regardless of the difference in the dimension in the A direction.

[0125] As described above, if the lateral swing amount of the first conveyor belt 8 is detected, the lateral swing correction mechanism 30 can correct the lateral swing of the first conveyor belt 8 based on the lateral swing amount.

[0126] [3. Effect]

[0127] As described above, the first conveyor belt 8 of the present embodiment has a plurality of marks 90 for position detection in the A direction which is the conveying direction of the first conveyor belt 8. Furthermore, each of the plurality of marks 90 has a first specific portion 91 whose size in the A direction is different depending on the position in the intersecting direction (e.g., the BB' direction) intersecting the A direction. Thus, the lateral swing amount in the intersecting direction of the first conveyor belt 8 can be detected based on the detection signal obtained by the belt sensor 25 reading the first specific portion 91 in the A direction.

[0128] Furthermore, since there are a plurality of marks 90 having the first specific portion 91 in the A direction on the first conveyor belt 8, even when the total circumference of the first conveyor belt 8 is increased, the lateral swing amount of the first conveyor belt 8 in the A direction can be accurately detected based on the detection signal of the first specific portion 91 of each mark 90. ​​As a result, even when the total circumference of the first conveyor belt 8 is increased, the lateral swing can be corrected with high accuracy.

[0129] In addition, each of the plurality of marks 90 has a second specific portion 92 whose size in the A direction is fixed regardless of the position in the cross direction. Furthermore, the plurality of marks 90 includes a reference mark 90a whose size in the A direction of the second specific portion 92 is different from that of other general marks 90b. Thus, regardless of whether there is lateral swing in the cross direction of the first conveyor belt 8 and the magnitude of the lateral swing, for example, based on the detection signal obtained by reading the second specific portion 92 in the A direction by the belt sensor 25, it is possible to detect whether the read mark 90 is the reference mark 90a or other general mark 90b. Furthermore, by detecting the reference mark 90a, the reference position of one cycle of the first conveyor belt 8 can be detected.

[0130] Furthermore, since each mark 90 has both the first specific portion 91 and the second specific portion 92, and the shape (outer shape) of the first specific portion 91 is made the same in the reference mark 90a and the normal mark 90b, and only the size of the second specific portion 92 in the A direction is made different, the reference position of one cycle of the first conveyor belt 8 and the lateral swing amount of the first conveyor belt 8 can be detected at the position of each mark 90 as described above. Therefore, the first conveyor belt 8 suitable for the above-mentioned detections can be realized with a simple structure.

[0131] In each mark 90, the first specific portion 91 and the second specific portion 92 are located side by side in the direction A. Thus, the detection of the lateral swing amount based on the reading of the first specific portion 91 and the detection of the reference position based on the reading of the second specific portion 92 can be continuously performed as the first conveyor belt 8 travels in the direction A.

[0132] In addition, in each mark 90, the second specific portion 92 is located downstream of the first specific portion 91 in the direction A. Thus, at the position of each mark 90, the reference position can be detected based on the reading of the second specific portion 92 first, and then the lateral swing amount can be detected based on the reading of the first specific portion 91.

[0133] In addition, at the same position in the intersecting direction intersecting with the A direction, that is, at the same reading position of the tape sensor 25, two points at both ends of the A direction of the first specific portion 91 (for example, the end X 12 、End X 14 ) (e.g., end X 12 ) and two points at both ends of the A direction of the second specific portion 92 (for example, the end X 11 、End X 12 ) (e.g., end X 12 In this structure, when reading both ends of the first specific portion 91 and the second specific portion 92 in the A direction, the points read at the same position in the cross direction are three points in total (end X 11 、End X 12 、End X 14 ). In this case, for example, compared with a structure in which the first specific portion 91 and the second specific portion 92 are separated in the A direction by different regions, and a total of four points, namely, two points at both ends of the first specific portion 91 in the A direction and two points at both ends of the second specific portion 92 in the A direction, are read at different times, the number of reading locations (number of times) is reduced. Thus, processing based on reading by the belt sensor 25 (detection of the reference position of one cycle of the first conveyor belt 8 and detection of the lateral swing amount) can be performed quickly and easily.

[0134] In addition, on the first conveyor belt 8, each mark 90 is located at a position separated in the A direction. And, the interval between the adjacent marks 90 in the A direction is longer than the above-mentioned maximum dimension of the mark (for example, the reference mark 90a) having the maximum dimension in the A direction among all the marks 90. In this structure, the detection signal of the mark 90 downstream in the A direction based on the belt sensor 25 and the detection signal of the mark 90 upstream can be reliably distinguished as detection signals of different marks 90. That is, it is possible to reliably avoid the situation where the detection signals of the adjacent marks 90 in the A direction interfere with each other and cannot be distinguished. Therefore, based on the detection signal of each mark 90, the reference position of one circle of the first conveyor belt 8 and the lateral swing amount can be reliably detected.

[0135] In addition, in each of the reference mark 90a and the normal mark 90b, the dimension of the first specific portion 91 in the direction A becomes longer as it goes from one side toward the other side (for example, from the belt end side toward the belt inner side) in the direction intersecting the direction A. In this case, the lateral swing amount of the first conveyor belt 8 can be reliably detected based on the detection signal (for example, the length of the high-level detection period) obtained by the belt sensor 25 reading the first specific portion 91 in the direction A.

[0136] In addition, the plurality of marks 90 include a first portion 91a and a second portion 92a located side by side in the A direction, with a portion of the first conveyor belt 8 as a separation area 91b. The first portion 91a is composed of a hole 91a1 or a reflective member 91a2. In addition, the second portion 92a is composed of a hole 92a1 or a reflective member 92a2. Furthermore, the first specific portion 91 is composed of the separation area 91b and the first portion 91a. In addition, the second specific portion 92 is composed of the second portion 92a.

[0137] Thus, by using the separation area 91b formed by a part of the first conveyor belt 8 and the first portion 91a formed by the hole 91a1 or the reflective member 91a2, the first specific portion 91 can be reliably realized. In addition, the second specific portion 92 can be reliably realized by the separate second portion 92a formed by the hole 92a1 or the reflective member 92a2.

[0138] In addition, in each mark 90, at any position in the intersecting direction intersecting with the A direction, the dimension of the A direction of the second specific part 92 is defined by the dimension of the A direction of the second part 92a. For example, in the reference mark 90a, the dimension of the A direction of the second specific part 92 is defined by the dimension La of the A direction of the second part 92a. In addition, in the normal mark 90b, the dimension of the A direction of the second specific part 92 is defined by the dimension Lb of the A direction of the second part 92a. The dimension La is different from the dimension Lb, and the dimension Lb is, for example, the same as the dimension Lz of the A direction of the first part 91a. Therefore, it can be considered that the dimension La of the A direction of the second specific part 92 of the reference mark 90a is different from the dimension Lb of the A direction of the second part 92a of the other normal marks 90b, and is also different from the dimension Lz of the A direction of the first part 91a of all the marks 90.

[0139] In this configuration, the belt sensor 25 can detect the second portion 92a of the reference mark 90a, distinguishing it from the second portion 92a of the normal mark 90b and the first portion 91a of all the marks 90. Thus, the reference position of one cycle of the first conveyor belt 8 can be easily detected based on the detection signal of the belt sensor 25.

[0140] In particular, in a configuration in which the dimension Lb of the second portion 92a of the normal mark 90b other than the reference mark 90a in the A direction is the same as the dimension Lz of the first portion 91a of all the marks 90 in the A direction, the second portion 92a of the reference mark 90a and other portions (e.g., the second portion 92a of the normal mark 90b and the first portion 91a of all the marks 90) can be clearly distinguished and detected by the belt sensor 25. Thus, it is easier to detect the reference position of one cycle of the first conveyor belt 8 based on the detection signal of the belt sensor 25. For example, as described above, it is possible to determine whether the belt sensor 25 has detected the reference mark 90a only by comparing the detection period of the second portion 92a with the threshold value (comparison of the elapsed time Tref with the threshold value Tth), thereby making it easier to detect the reference position of one cycle of the first conveyor belt 8.

[0141] Furthermore, the printer 100 as the recording device of the present embodiment includes the first conveyor belt 8 described above, and records an image on the paper P as the recording medium using the first conveyor belt 8. In this case, in the printer 100 that records an image on the paper P by ejecting ink, a structure that detects a reference position of one circle of the first conveyor belt 8 and detects a lateral swing amount in a cross direction can be realized.

[0142] In particular, the printer 100 of this embodiment includes, in addition to the first conveyor belt 8, recording heads 17a to 17c having a plurality of nozzles (ink ejection ports 18) for ejecting ink, a belt sensor 25 as an optical sensor for detecting a plurality of marks 90 provided on the first conveyor belt 8, a reference position calculation unit 113, and a control unit 111. The first conveyor belt 8 transports the paper P to a position opposite to the recording heads 17a to 17c, and in addition to the plurality of marks 90, has openings 80 or an opening group 82 including the openings 80 at irregular intervals at a plurality of locations in the A direction for passing the ink ejected from the recording heads 17a to 17c during the flushing operation.

[0143] In this structure, the reference position calculation unit 113 obtains the reference position of one cycle of the first conveyor belt 8 based on the detection results of the plurality of marks 90 of the belt sensor 25. Furthermore, the control unit 111 detects (determines) the position of the opening 80 (opening group 82) used for the flushing operation based on the reference position obtained by the reference position calculation unit 113, and causes the recording heads 17a to 17c to perform the flushing operation at a timing when the determined opening 80 (opening group 82) faces the recording heads 17a to 17c by the travel of the first conveyor belt 8.

[0144] When the flushing operation is performed, the ink ejected from the recording heads 17a to 17c passes through the opening 80, so the first conveyor belt 8 is not contaminated by the ink, and the effect of the flushing operation (the effect of preventing nozzle clogging due to drying of the ink) can be obtained. In addition, since the first conveyor belt 8 has the openings 80 (opening group 82) at irregular intervals at multiple locations in the A direction, the openings 80 used in the flushing operation can be selected according to the size of the paper P used. Therefore, the flushing operation can be performed after the position of the opening 80 corresponding to the size of the paper P used is determined based on the above-mentioned reference position.

[0145] The printer 100 of this embodiment further includes a pair of resist rollers 13 as a recording medium supply unit for supplying the paper P to the first conveyor belt 8. The control unit 111 controls the pair of resist rollers 13 to supply the paper P to the first conveyor belt 8 (see FIG. 11 ). Figure 7 to Figure 10 ) to place the paper P in a predetermined positional relationship with the determined opening 80 (opening group 82) in the direction A (for example, to place the paper P in a manner offset from the opening 80 in the upstream of the conveying direction). In this control, before the paper P supplied to the first conveyor belt 8 by the registration roller pair 13 and placed is subjected to ink ejection to record an image, the opening 80 can be flushed. Thus, after the flushing operation, an image with good image quality can be recorded on the paper P by ejecting ink.

[0146] In addition, the printer 100 of the present embodiment includes a shielding circuit 112 that extracts and outputs only signals that last for a specified period or longer from the detection signals of the plurality of markers 90 output by the tape sensor 25. Further, the reference position calculation unit 113 obtains the reference position of one circumference of the first conveyor belt based on the signal output from the shielding circuit 112. By using the shielding circuit 112, it is possible to extract only the signals necessary for detecting the reference position from the detection signals of the tape sensor 25, and thus it is possible to easily detect the reference position (based on the electrical signal).

[0147] In addition, in the printer 100 of the present embodiment, the lateral swing amount calculation unit 114 obtains the lateral swing amount of the first conveyor belt 8 based on the detection results of the plurality of markers 90 of the tape sensor 25. Further, the lateral swing correction mechanism 30 corrects the lateral swing of the first conveyor belt 8 based on the lateral swing amount obtained by the lateral swing amount calculation unit 114. With the structure of each of the above markers 90, it is possible to appropriately obtain the lateral swing amount of the first conveyor belt 8. Therefore, the lateral swing correction mechanism 30 can appropriately correct the lateral swing of the first conveyor belt 8 based on the lateral swing amount.

[0148] (4. Modification example)

[0149] Fig. 20 is a plan view showing another configuration example of the first conveyor belt 8. In Fig. 20 in the shown first conveyor belt 8, in a structure where the plurality of markers 90 are located at three or more positions in the A direction, in addition to the reference marker 90a, other reference markers 90c are provided.

[0150] Fig.21 is a plan view showing a configuration example of one of the other reference markers 90c. The reference marker 90c has the same structure as the reference marker 90a except that the dimension Lc (mm) in the A direction of the second part 92a constituting the second specific part 92 is different from that of the reference marker 90a. For example, the dimension Lc in the A direction of the second part 92a of the reference marker 90c is set so as to satisfy Lb < Lc < La. As a result, when the maximum dimension in the A direction of the reference marker 90c is set to Lmax3 (mm), Lmax2 < Lmax3 < Lmax1. In addition, the size relationship between Lc and La and the size relationship between Lmax3 and Lmax1 may be reversed.

[0151] Thus, the plurality of marks 90 provided on the first conveyor belt 8 include the plurality of reference marks 90a and 90c whose dimensions in the A direction are different from each other in the second specific portion 92, thereby achieving the following effects. That is, for example, a certain reference position of one cycle of the first conveyor belt 8 can be detected based on the detection signal obtained by the belt sensor 25 reading the reference mark 90a, and the position of a certain opening group 82 (for example, the opening group 82A) can be detected based on the detection result. In addition, other reference positions of one cycle of the first conveyor belt 8 can be detected based on the detection signal obtained by the belt sensor 25 reading the reference mark 90c, and the position of other opening groups 82 (for example, the opening group 82B) can be detected based on the detection result. Therefore, even if the opening group 82 that serves as a reference when placing the paper P differs depending on the size of the paper P used, the paper P can be supplied and placed on the first conveyor belt 8 in a manner that the paper P is placed in a predetermined positional relationship with respect to the reference opening group 82 corresponding to the size of the paper P.

[0152] In addition, one or more reference marks may be provided on the first conveyor belt 8 in addition to the reference marks 90a and 90c. That is, a total of three or more reference marks having different dimensions in the A direction of the second specific portion 92 may be provided on the first conveyor belt 8.

[0153] (5. Others)

[0154] In each mark 90 of the first conveyor belt 8, the first specific portion 91 may include an area whose size in the A direction is the same regardless of the position in the cross direction. In this case, the portion other than the above-mentioned area in the first specific portion 91 substantially constitutes the first specific portion 91 whose size in the A direction is different depending on the position in the cross direction.

[0155] In the present embodiment, the maximum dimension of the first specific portion 91 in the direction A is the same in all the marks 90 . However, the maximum dimension of the first specific portion 91 in the direction A of some marks 90 may be different from that of other marks 90 .

[0156] In the present embodiment, a structure in which a plurality of marks 90 are provided on the first conveyor belt 8 of the printer 100 mounted as an inkjet recording device is described, but the plurality of marks 90 described in the present embodiment can also be applied to belts of other recording devices. For example, on the intermediate transfer belt of a color copier, in order to correct the lateral swing of the intermediate transfer belt, it is necessary to detect the amount of lateral swing. In addition, in order to transfer the colorant images of each color at the same position during calibration, the reference position of one circle of the intermediate transfer belt is sometimes detected. By applying the plurality of marks 90 described in the present embodiment to the intermediate transfer belt of an image forming device (recording device) such as a copier, both the reference position detection of one circle of the intermediate transfer belt and the lateral swing amount detection of the intermediate transfer belt can be performed.

[0157] In the above, the case where the paper P is adsorbed to the first conveyor belt 8 and conveyed by negative pressure suction is described, but the first conveyor belt 8 may be charged, and the paper P may be electrostatically adsorbed to the first conveyor belt 8 and conveyed (electrostatic adsorption method). In this case, a structure in which a plurality of marks 90 are provided may also be applied to the first conveyor belt 8.

[0158] In the above, an example of a color printer that uses four-color ink to record color images is described as an inkjet recording device, but the structure of this embodiment (especially the structure of providing multiple marks 90 on the first conveyor belt 8) can also be applied when using a black and white printer that uses black ink to record black and white images.

[0159] Industrial Applicability

[0160] The belt of the recording device of the present invention can be applied to a paper conveying belt used in an inkjet printer, an intermediate transfer belt used in an image forming apparatus such as a copying machine, etc.

[0161] Description of Reference Numerals

[0162] 8. First conveyor belt (belt)

[0163] 13 Registration roller pair (recording medium supply unit)

[0164] 17a~17c Recording head

[0165] 18 ink ejection outlet (nozzle)

[0166] 25 with sensor (optical sensor)

[0167] 30 Lateral swing correction mechanism

[0168] 80 Opening

[0169] 90 Mark

[0170] 90a Benchmark

[0171] 90b Normal mark (other marks)

[0172] 90c Benchmark

[0173] 91 First specific part

[0174] 91a First part

[0175] 91a1 hole

[0176] 91a2 Reflection member

[0177] 91b Separation Area

[0178] 92 Second specific part

[0179] 92a Second part

[0180] 92a1 hole

[0181] 92a2 Reflection member

[0182] 100 printer (recording device)

[0183] 111 Control Department

[0184] 112 Shielding Circuit

[0185] 113 Reference position calculation unit

[0186] 114 Horizontal swing amount calculation unit

Claims

1. A tape for a recording device, characterized in that There are a plurality of marks for detecting the position of the belt in the conveying direction of the belt, The plurality of tags respectively have: a first specific portion, wherein the dimension in the conveying direction is different depending on the position of a crossing direction crossing the conveying direction; and The second specific part has a dimension in the conveying direction that is independent of the position in the crossing direction and is a fixed dimension. The plurality of marks include a reference mark, and a dimension of the second specific portion of the reference mark in the conveying direction is different from those of the other marks.

2. The tape of the recording device according to claim 1, characterized in that In each of the marks, the first specific portion and the second specific portion are located side by side in the conveying direction.

3. The tape of the recording device according to claim 2, characterized in that In each of the marks, the second specific portion is located downstream in the conveying direction relative to the first specific portion.

4. The tape of the recording device according to claim 1, characterized in that At the same position in the intersecting direction, one point at both ends of the first specific portion in the conveying direction and one point at both ends of the second specific portion in the conveying direction are the same point.

5. The tape of the recording device according to claim 1, characterized in that The marks are located at positions separated in the conveying direction, The interval between the marks adjacent to each other in the conveying direction is longer than the maximum dimension of a mark having the maximum dimension in the conveying direction among all the marks.

6. The tape of the recording device according to claim 1, characterized in that A dimension of the first specific portion in the conveying direction increases from one side toward the other side of the intersecting direction.

7. The tape of the recording device according to claim 1, characterized in that The plurality of marks are located at three or more positions in the conveying direction and include a plurality of the reference marks, Among the plurality of reference marks, dimensions of the second specific portion in the conveying direction are different from each other.

8. The tape of the recording device according to claim 1, characterized in that Each of the plurality of marks includes a first portion and a second portion located side by side in the conveying direction across a portion of the belt as a separation region. The first portion and the second portion are formed by a hole or a reflective member, The first specific portion is composed of the separation area and the first part, The second specific portion is constituted by the second part.

9. The tape for recording device according to claim 8, characterized in that At any position in the cross direction, the dimension of the second specific portion in the conveying direction is defined by the dimension of the second portion in the conveying direction. A size of the second specific portion of the reference mark in the conveyance direction is different from a size of the second portion of the other marks in the conveyance direction and a size of the first portion of all marks in the conveyance direction.

10. The tape of the recording device according to claim 9, characterized in that The size of the second portion of the other mark in the conveying direction is the same as the size of the first portion of all marks in the conveying direction.

11. A recording device, characterized in that: The tape according to any one of claims 1 to 10 is included, and an image is recorded on a recording medium using the tape.

12. The recording device according to claim 11, characterized in that include: a recording head having a plurality of nozzles for ejecting ink; a conveyor belt as the belt, conveying the recording medium to a position opposite to the recording head, and having openings at irregular intervals at a plurality of locations in the conveying direction, the openings allowing the ink to pass when the recording head performs a flushing action, wherein the flushing action ejects the ink at a timing different from a timing of forming an image on the recording medium; An optical sensor for detecting a plurality of the marks disposed on the conveyor belt; a reference position calculation unit for obtaining a reference position of one circle of the conveyor belt based on detection results of the plurality of marks by the optical sensor; as well as a control unit that controls ejection of the ink in the recording head, The control unit determines the position of the opening for the flushing operation based on the reference position of the conveyor belt throughout a circle obtained by the reference position calculation unit, and causes the recording head to perform the flushing operation when the determined opening faces the recording head due to the travel of the conveyor belt.

13. The recording device according to claim 12, characterized in that further comprising a recording medium supplying unit for supplying the recording medium to the conveyor belt, The control unit controls the recording medium supply unit to supply the recording medium to the conveying belt so that the recording medium is placed in a predetermined positional relationship with the determined opening in the conveying direction.

14. The recording device according to claim 12, characterized in that It also includes a mask circuit that extracts and outputs only signals that are longer than a predetermined period from the detection signals of the plurality of marks output by the optical sensor, The reference position calculation unit obtains a reference position of one circumference of the conveyor belt based on the signal output from the mask circuit.

15. The recording device according to claim 12, characterized in that Also includes: a lateral swing amount calculation unit for calculating the lateral swing amount of the conveyor belt in the cross direction based on the detection results of the plurality of the marks by the optical sensor; as well as The lateral swing correction mechanism corrects the lateral swing of the conveyor belt based on the lateral swing amount obtained by the lateral swing amount calculation unit.

Images