JP2011224826A - Recording device and recording method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid positional deviation between an image and a recording paper for obtaining a high-grade printed matter.SOLUTION: A generation range of expansion and contraction which is generated in the width direction of the recording paper is identified from a tip of the recording paper during the period from setting the recording paper to an introduction part of a conveying system until the time immediately before print start. An image is recorded by adjusting a print start position for the recording paper according to a specified generation range of the expansion and contraction.

Description

  The present invention relates to a recording apparatus and a recording method, such as a large copying machine and a plotter, which form an image on recording paper.

  For example, the size of recording paper such as plain paper and tracing paper expands and contracts due to changes in temperature and humidity. For this reason, for example, Patent Document 1 detects the edge position of the set recording paper and the width of the recording paper in a series of initial operations before printing, and detects the positional deviation of the image with respect to the recording paper. A technique for correcting is disclosed.

JP 2000-109243 A

  By the way, if the surrounding environment of the recording apparatus such as temperature and humidity changes after the recording sheet is set in the recording apparatus so that printing can be performed, the recording sheet may expand and contract. If the recording paper expands or contracts after the recording paper is set in the recording apparatus, there is a problem that the position of the image printed on the recording paper is shifted.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to suppress a decrease in print quality due to the expansion and contraction of the recording paper that occurs after the recording paper is set so that printing is possible. It is to provide a recording apparatus.

  The present invention relates to the expansion and contraction for specifying the generation range from the leading edge of the recording paper that occurs in the width direction of the recording paper between the time when the recording paper is set at the introduction part of the transport system and immediately before the start of printing. The image processing apparatus includes: a range specifying unit; and a control unit that records an image by adjusting a recording start position with respect to a recording sheet according to an expansion / contraction generation range specified by the expansion / contraction range specifying unit.

  According to the present invention, it is possible to avoid misalignment between an image and a recording sheet and obtain a high-quality printed matter.

1 is an overall schematic configuration diagram of a recording apparatus according to an embodiment of the present invention. It is a block diagram of a cutter unit. It is a schematic diagram of a recording paper detection unit. It is a block diagram which shows the structure of a recording device. FIG. 6 is a diagram illustrating a detection operation position when a paper is set. It is a perspective view which shows the force which acts on a recording paper. It is a figure which shows the state of a recording paper, and a detection operation position figure. 6 is a flowchart illustrating an example of a print control process. 10 is a flowchart illustrating another example of print control processing. It is a figure which shows the expansion-contraction area | region profile of a recording paper.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of an entire recording apparatus according to an embodiment of the present invention. The recording apparatus 1 includes a roll paper holder unit 10, an image forming unit 20, and a paper discharge unit 30.

  The roll paper holder unit 10 is an introduction unit that feeds the roll-shaped recording paper PR to the transport system, and holds the roll-shaped recording paper PR rotatably. The image forming unit 20 forms an image while holding the recording paper fed from the roll paper holder unit 10. The paper discharge unit 30 cuts the recording paper after image formation and discharges the recording paper to the outside of the apparatus.

  The roll paper holder unit 10 is configured so that the recording paper PR is rotatably held by the spool shaft 11 and the pair of spool flanges 12L and 12R, and both ends of the spool shaft 11 are received by the spool bearing portions 13L and 13R. In order to easily replace the recording paper PR, there are slide slopes 13′L and 13′R in front of the bearing portions 13L and 13R, and the operator can follow the recording paper PR along the slopes. Desorption of. A pair of paper feed guides is provided below the recording paper PR to support the operator when the paper is fed to an image forming unit 20 described later.

  The image forming unit 20 includes an LF roller 21, a plurality of pinch rollers 22, a platen 23, and a carriage 40. The LF roller 21 is for conveying a predetermined amount of recording paper during image formation. The plurality of pinch rollers 22 are driven to rotate while being urged toward the LF roller 21 with a predetermined pressure F. The platen 23 holds the paper in a flat shape while sucking the paper through the suction holes 23a. The carriage 40 holds the recording head 41 and reciprocally scans in a paper conveyance direction Y (referred to as the sub-scanning direction) and a direction perpendicular to the paper transport direction Y (referred to as the main scanning direction) X.

  The recording head 41 is a well-known ink jet system, and ink droplets are applied to the recording paper PR by a head driving signal based on image data generated in synchronization with the reciprocating movement operation of the carriage 40 holding the ink jet in the main scanning direction. Dispense toward. Thereby, the recording head 41 records an image. An image is formed on the recording paper while alternately repeating a predetermined amount of conveyance (referred to as band conveyance) by the LF roller 21 and recording by the carriage 40. A cutter unit 50 that cuts the recording paper PR while moving in the main scanning direction (−X direction) is detachably provided at the left end of the carriage 40.

  FIG. 2 is a configuration diagram of the cutter unit. A cutter blade 51 that directly contacts the recording paper PR and cuts the recording paper PR is fixed to the cutter unit 50. In the portion of the platen 23 where the cutter blade 51 moves, a cutter groove 23b into which the tip of the cutter blade 51 enters is formed.

  A cutter slider 53 that can move up and down is provided inside the cutter holder 52, and a guide roller 54 that rotatably holds the cutter blade is attached to the cutter slider 53. When the cutter blade 51 moves to the storage position 51 ′, the guide roller 54 is pushed upward along the guide rib 23 c (see FIG. 1) formed on the platen 23 and stored in the cutter holder 52. A cutter spring 55, which is a compression coil spring, is provided on the upper portion of the cutter slider 53. The cutter blade 51 is urged downward by the cutter spring 55, and this urging force F applies a tension to the recording paper at the time of cutting. A claw portion 53a is provided at the upper end portion of the cutter slider 53, and the claw portion 53a is selectively locked with the ribs 52b and 52c of the cutter holder 52 to fix the vertical position. At the time of cutting the recording paper, when the carriage 40 overruns to the leftmost part of the main body 1, the claw portion 53a is pushed and released by the projection 2 provided on the wall. The claw portion 53a is moved downward by the cutter spring 55 to a position (cutting position) where it is locked by the rib 52c, and performs the aforementioned cutting operation.

  As shown in FIG. 1, a recording paper detection unit 60 as a recording paper detection unit is provided at the left end of the carriage 40. The structure of the recording sheet detection unit 60 will be described with reference to the schematic diagram of the recording sheet detection unit in FIG. The recording paper detection unit 60 is a reflective optical sensor and includes a light emitting diode 61 (LED) that is a light emitting unit and a phototransistor (or photodiode) that is a light receiving unit 62. Then, the recording paper detection unit 60 irradiates the surface of the recording paper PR from the LED 61 and detects reflected light from the recording paper PR by the phototransistor 62 to detect the recording paper PR. The recording paper detection unit 60 can use any sensor as long as it can detect the presence or absence of recording paper.

  FIG. 4 is a block diagram showing an example of a control system of the recording apparatus to which the present invention is applied. In FIG. 4, the control unit 100 controls the entire recording apparatus and constitutes an expansion / contraction range specifying unit and a control unit of the present invention. An I / F (interface) unit 104 and a host computer (not shown) are connected. A command and recording data for printing are sent from the host computer, and the recording apparatus operates in accordance with the command to perform recording on the recording paper. Further, it is possible to notify the status of the recording apparatus by sending a command and data of the information of the recording apparatus to the host computer, and thereby it is possible to notify the user of paper information. In general, a Centronics and USB interface are often used as the I / F unit 104. The image processing unit 101 executes processes such as γ correction, color processing, enlargement / reduction processing, and binarization on the recording data (multi-valued image data) sent from the I / F unit 104. The image processing unit 101 includes, for example, a memory, an ASIC and DSP, a RISC chip, and the like. The configuration and function of the image processing unit may be configured to be processed by a host-side driver or RIP (Raster Image Processor) in order to reduce the main body cost. The print data developed into a dot pattern at the final stage of processing in the image processing unit 101 is temporarily stored in the memory unit 106. The memory unit 106 includes a memory for one band or more necessary for recording by a recording head (not shown) once scanning in the main scanning direction. The memory unit 106 is also used for storing information such as paper information. The sheet information includes information that is stored as needed every time it is changed, and information that is stored immediately before the power is shut off because it continuously changes during printing, such as the position of the leading edge of the sheet. Writing / reading of print data to / from the memory unit 106 is performed by the memory controller 105 under the control of the DSP or RISC chip of the image processing unit 101. The memory controller 105 generates an address signal and a write / read timing signal for the memory unit 106. The print data read from the memory unit 106 is output to the head controller 107 in synchronization with a read signal from the head controller 107. The head controller 107 generates an ink discharge timing signal and a heat pulse in the head unit 108 under the control of the control unit 100 based on a signal from a linear scale (not shown). The head unit 108 is composed of a recording head corresponding to each color ink, and heats the heater unit by the control unit 100 and the head controller 107 to eject ink, thereby recording an image on a recording sheet. The head unit 108 is actually mounted on the carriage 40 shown in FIG. The mechanical drive unit 103 includes a motor for moving the recording head and recording paper, a paper driving unit including an encoder and a paper presence sensor for detecting the rotation of the motor, a recovery unit unit for recovering ink clogging of the recording head, and the like. The detection value of the encoder in the paper transport unit is used for the calculation of the control unit, and the motor is controlled by the control unit. The control unit also calculates the leading end position of the recording sheet and specifies the leading end position of the recording sheet. In this embodiment, the control unit is configured by software and necessary hardware, but the control unit may be configured by a circuit.

  Next, the process until the recording paper PR (roll paper) is set in the recording apparatus in a state where printing can be started will be described. First, the operator releases the nip by the pinch roller 22 with a release lever (not shown), and sends the recording paper PR to the image forming unit 20. The right end of the recording paper PR is aligned with the set mark 31a of the roll paper cover 31 and is nipped by the pinch roller 22 by the release lever. Starting from this operation, the following paper edge detection operation is started. This is called a pre-feed operation.

  In this embodiment, the side closer to the standby position (referred to as the home position) of the carriage 40 is set to the right and the side far from the left is set to the left, and the detection operation is performed from the right to the left of the recording paper PR in order to shorten the detection operation time. To do. However, when the home position is reversed, it is preferable to perform the detection operation from left to right.

Detection operation (1)
The carriage 40 is moved in the + X direction, and the carriage 40 is stopped at a position where the recording sheet detection unit 60 is positioned on the right end of the sheet (as viewed from the front side of the main body). While the recording paper detection unit 60 detects the recording paper PR, the LF roller 21 back-feeds the recording paper PR in the −Y direction to detect the right leading Y1 of the paper PR.

Detection operation (2)
Next, the recording paper PR is fed in the + Y direction to a predetermined position. The position (reference position) of the right front end X1 of the paper is detected by scanning the carriage 40 in the −X direction while detecting the stopped recording paper PR by the recording paper detection unit 60.

Detection operation (3)
Next, the recording paper PR is fed in a predetermined amount L (300 mm in this example) + Y direction. The position of the right end X2 of the paper PR is detected by reciprocating the carriage 40 with respect to the recording paper PR while detecting the recording paper PR stopped by the recording paper detection unit 60.

Detection operation (4)
Next, while the recording paper PR is detected by the recording paper detection unit 60, the width of the recording paper PR is detected by scanning the carriage 40 in the + X direction (main scanning direction).

Detection operation (5)
The carriage 40 is moved in the −X direction, and the recording paper detection unit 60 is stopped at a position located at the left end (viewed from the front side of the main body) of the paper PR. Next, while the recording paper PR is detected by the recording paper detection unit 60, the position of the left end Y2 of the paper PR is detected by back feeding the recording paper PR in the -Y direction.

Detection operation (6)
Of the right end Y1 and the left end Y2, the recording sheet PR is moved to a position within the recording sheet PR where the distance from the leading end on the upstream side (side closer to the LF roller) to the recording sheet detection unit 60 is a predetermined distance S. Feed in + Y direction.

  Thereafter, the carriage 40 is scanned in the −X direction while being detected by the recording paper detection unit 60, thereby detecting the presence or absence of paper in the entire paper width. The predetermined distance S depends on the detection range (= spot diameter) of the recording paper detection unit 60. In this example, since the spot diameter is Φ3 mm, the predetermined distance S is set to 2 mm in consideration of a margin. Further, the predetermined distance S is set to be equal to or less than the front end margin (5 mm in this example) of the apparatus. In this way, it is possible to prevent the occurrence of a printing defect in which the recording paper PR is surely present at the printing start position and printing directly on the platen. The tip detection position is preferably determined according to the spot diameter and the tip margin set amount.

  When the above series of detection operations is completed, the recording paper PR is back-fed to the standby position in the -Y direction, and the carriage is moved to the standby position in the -X direction to enter a standby state. Further, the width of the paper PR detected in the detection operation (4) and the position of each detected edge are stored in the memory unit 106. As described above, in the present embodiment, it is necessary to change the relative positional relationship between the recording sheet and the recording sheet detection unit by moving the carriage and the recording sheet PR by the transport system, and to specify the expansion / contraction occurrence range. The position information of the correct recording paper PR is acquired.

  Here, a change occurring in the recording paper PR stopped at the standby position will be described with reference to FIGS. It has been found that the recording paper PR itself expands and contracts due to the influence of the surrounding temperature and humidity environment. The entire surface of the recording paper does not expand and contract evenly at a time, but expands and contracts in a direction in which it easily expands and contracts. In addition, expansion and contraction occur from locations where the recording paper is easily touched by the environment. This also depends on the elapsed time. For example, the amount of expansion / contraction in each of the areas A to E shown in FIG. 6 is different and shows a tendency as shown in FIG. A is the front end area A of the recording paper PR, B is the area where the recording paper PR is completely separated from the roll, C is the area where the recording paper PR begins to leave the roll, D is the outer area within the roll, and E is the roll. The center region of each is shown. Generally, since the fiber direction of the paper is oriented in the width direction, the paper tends to expand and contract in the width direction. Further, the region closer to the LF roller 21 and the pinch roller 22 tends to stretch and shrink. When the leading end portion of the recording paper PR is fixed by the LF roller 21 and the pinch roller 22 and tension is applied toward the roll, the force for expanding and contracting the recording paper PR is increased toward the center of the roll. It becomes difficult to work. However, for example, when left for a long time of several days, a week, or longer, each region expands and contracts in substantially the same manner.

Detection operation (7)
In consideration of the expansion / contraction characteristics of the recording paper PR, it is necessary to confirm whether the recording paper PR is stopped at the standby position before the printing operation is started. This will be described with reference to FIG. First, at the right end X1, the detection operation (4) is performed to detect the width of the recording paper PR. The detected width is compared with the width detected at the time of setting the paper. If there is a difference between the two, the carriage is moved to the reference position M1 of the previous detection, and the recording paper PR is fed in the + Y direction and expanded or contracted. Detection of the position F of the recording paper PR not being used is performed. Next, the carriage is moved to the position M2 of the left end detected last time, and the position E in the Y direction of the recording paper PR whose left end is not expanded or contracted again is detected. The range from the leading end of the recording paper PR to the position E is an occurrence range in which expansion and contraction occurs due to the influence of the environment.

Detection operation (7) -1
In the above detection operation (7), when a temperature / humidity sensor (not shown) and a timer are used, not only before the printing operation starts but also when a change in temperature / humidity and a certain time elapses. This can only be done when the above conditions are met. The timer counts the elapsed time from the time when the recording paper is set. When the recording paper PR is set, the temperature Ts and humidity Hs are detected using the temperature and humidity sensor and stored in the memory unit 106. When a change occurs in the temperature / humidity sensor after the recording paper is set, the temperature Ts2, humidity Hs2, and timer time ts2 at that time are recorded in the memory unit 106. When the predetermined time tα or more has elapsed from the timer time ts2, the detection operation (7) is executed to detect the expansion / contraction range of the recording paper PR.

Detection operation (7) -2
Further, for example, the influence rate α defined by the following equation (1) is obtained from the temperature change amount, the humidity change amount, and the elapsed time. Then, as shown in FIG. 10, from the profile that defines the relationship between the influence rate α experimentally known in advance and the range Ya (mm) in the transport direction Y affected by the expansion / contraction of the recording paper PR, The shrinkage range Ya can be predicted. This is effective in a recording apparatus that does not include an optical sensor.

  α = ((temperature difference (Ts2−Ts) × influence rate α1) + (humidity difference (Hs) 2−Hs) × influence rate α2))) × tα (1)

  Next, with reference to FIGS. 8 and 9, the flow of print control according to the expansion / contraction region of the recording paper PR detected by each detection operation will be described.

  At the start of printing, the received data is judged to be borderless printing (step S1). The borderless printing is printing in which an image is recorded up to the peripheral edge of the recording medium PR, and the bordered printing is printing in which an image is not recorded on the peripheral edge of the recording paper. In case of borderless printing, since the width of the print data and the width of the recording paper PR do not match, printing cannot be performed as it is. Therefore, the recording paper PR is fed in the transport direction Y so that the edgeless leading edge cutting is performed at the position E that is identified by the above-described detection operation and is equal to the width when the recording paper PR is set (step S2). As a result, the expansion / contraction occurrence range of the recording paper PR can be sent in the transport direction, and the recording start position for the recording paper PR can be adjusted out of the generation range. After the feed is completed, normal borderless printing is started (step S3). In the middle of printing, a front end cut is made (step S4), printing is performed again (step S5), and a rear end cut (step S6). After that, printing is completed.

  Note that when the recording apparatus includes a print data storage unit such as a large-capacity storage device (not shown) and can store the print data, the control shown in FIG. 9 can be executed. In FIG. 9, each step other than steps S10 and S11 is the same processing as in FIG. If it is borderless printing, it is determined whether there is a print data storage area (step S10). If there is a storage area, the print data is temporarily stored (step S11). After that, perform bordered printing, etc., and after the expansion / contraction area specified in the detection operation is used and cut by printing other print data other than print data for borderless printing, printing is resumed and borderless printing is performed. I do. By performing such control, it is possible to suppress consumption of useless recording paper PR.

  Returning to FIG. 8 again, a case where the printing is not marginal printing but marginal printing will be described. In the case of bordered printing, it is determined whether the amount of expansion / contraction in the left-right width direction specified by the detection operation is equal to the left-right (step S7). If the expansion and contraction is equal, printing is performed on the recording paper PR as it is (step S9). As a result, an image is printed on the central portion of the recording paper PR. However, if the left and right expansion / contraction amounts are not uniform and the expansion / contraction amounts are different in the transport direction, an image forming area estimated to be approximately the center in the width direction is specified, and the recording to the right end position (reference position) is performed. The start position is shifted and printing is started (step S8). That is, an image forming area in which an image is to be formed on the recording paper PR is substantially in the width direction of the recording paper PR in accordance with the position of each end in the width direction of the recording paper PR in the specified expansion / contraction occurrence range. Adjust the recording start position so that it is positioned in the center.

  In the present embodiment, the temperature / humidity sensor is used as the environmental information acquisition means. However, a sensor that detects one of temperature and humidity may be used. In this case, one of temperature and humidity can be used for expansion / contraction detection. It is also possible to detect expansion / contraction using any one of temperature, humidity, and elapsed time, or using these two.

  In the present embodiment, the expansion / contraction occurrence range is specified immediately before the start of printing, but the timing for specifying the expansion / contraction generation range is not limited to this. For example, the expansion / contraction occurrence range may be specified when a certain time has elapsed since the recording paper was set.

DESCRIPTION OF SYMBOLS 1 ... Recording apparatus 10 ... Roll paper holder part (introduction part)
100: Control unit (control means, expansion / contraction range specifying means)

Claims (8)

Expansion / contraction range specifying means for specifying the generation range in the conveyance direction of the expansion / contraction generated in the width direction of the recording paper after the recording paper is set in the introduction part of the conveyance system;
And a control unit configured to record an image by adjusting a recording start position with respect to the recording sheet in accordance with an expansion / contraction generation range specified by the expansion / contraction range specifying unit.   The recording apparatus according to claim 1, wherein the expansion / contraction range specifying unit specifies a generation range in the conveyance direction of the expansion / contraction immediately before starting printing.   The expansion / contraction range specifying means specifies the occurrence range of the expansion / contraction using at least one of temperature change, humidity change, and elapsed time since the recording paper is set in the conveyance system. The recording apparatus according to claim 1, wherein the recording apparatus is a recording apparatus. Recording paper detecting means provided on a carriage that holds a recording head for recording an image on the recording paper and moves in the main scanning direction;
The expansion / contraction range specifying means changes the relative positional relationship between the recording paper and the recording paper detection means by the movement of the carriage and the movement of the recording paper by the transport system, and specifies the range where the expansion / contraction occurs. The recording apparatus according to claim 1, wherein position information of a recording sheet necessary for recording is acquired.   When performing printing with a border that does not record an image on the peripheral edge of the recording paper, the control means is positioned at each end in the width direction of the recording paper in the expansion / contraction occurrence range specified by the expansion / contraction range specifying means. The recording start position is adjusted so that an image forming area in which an image is to be formed on the recording paper is positioned substantially at the center in the width direction of the recording paper. 5. The recording device according to any one of 4.   When performing borderless printing for recording an image up to the peripheral edge of the recording paper, the control means sends the expansion / contraction occurrence range specified by the expansion / contraction range specifying means of the recording paper in the transport direction, 6. The recording apparatus according to claim 1, wherein the recording start position is adjusted. A storage unit capable of storing print data of an image to be recorded on the recording paper;
When executing borderless printing for recording an image up to the peripheral edge of the recording paper, the control means temporarily stores print data for borderless printing in the storage means, and specifies the expansion / contraction range of the recording paper. After the range of occurrence of expansion / contraction specified by the means is used and consumed for recording by print data other than the print data for borderless printing, the recording by the print data stored in the storage means is executed. The recording apparatus according to claim 1, wherein the recording apparatus is a recording apparatus. Specifying the generation range in the conveyance direction of the recording paper in the width direction of the recording paper after the recording paper is set in the introduction part of the conveyance system; and
A recording method comprising: recording an image by adjusting a recording start position on a recording sheet in accordance with a specified expansion / contraction occurrence range.

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