JP2000190481A - Ink jet recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a substantial improvement in throughput by shortening a time before next printing is started without damaging printed images. SOLUTION: A medium 202 is transferred on a platen 201 and ink drops are discharged from a head 205. At this time, the medium is sucked onto the platen via medium suction holes 208 by a medium-sucking fan 204 so as to prevent the medium from floating and cockling. The printed medium is cut by a cutter at a cutter notch 209. The medium suction holes 208 are set to both the upstream side and the downstream side of a cut position, and the sucking fan rotates for a predetermined time after the end of printing as well as during printing, with holding the medium piece on the platen until the ink on the medium piece is dried. An initial operation for next printing is carried out while the ink is dried.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus having a media suction fan for sucking a medium onto a platen, and more particularly, to an ink jet recording apparatus using roll paper as a medium and having an automatic cut function. About.

[0002]

2. Description of the Related Art Conventionally, in an ink jet recording apparatus using a roll paper as a medium and having an automatic cut function, the medium is cut and ejected after a lapse of time in consideration of an ink drying time after printing is completed. You.

[0003]

That is, according to the conventional method, as shown in the flowchart of FIG. 7, after the medium is set, data is received, and after a predetermined initial operation, the suction fan is turned on to perform the printing operation. Start. Even after the printing operation is completed, the apparatus waits until the drying time elapses, and when the drying time elapses, cuts the medium, turns off the suction fan, and shifts to printing of the next image.
This is because if the ink is discharged immediately after printing, the printed image may be stained before drying because the ink is not dried.

Therefore, if it is desired to print the next image immediately after printing one image (page), it is necessary to wait for the time required for drying the ink relating to the previous printing. That is, the actual printing time includes the drying time of the ink. As a result, the actual throughput decreases.

The present invention has been made in order to solve such a problem, and realizes a substantial improvement in throughput by shortening the time until the next printing is started without damaging a printed image. Is what you do.

[0006]

According to the present invention, there is provided an ink jet recording apparatus comprising: a medium conveying means for conveying a medium on a platen; a printing means for performing printing by discharging ink droplets onto the conveyed medium; A media suction fan for sucking the media onto the platen through a media suction hole provided in the cutter, a cutter for cutting the printed media, and control means for controlling the media suction fan, Media suction holes are provided on both the upstream side and the downstream side of the cutting position of the cutter, and the control means rotates the suction fan during printing and performs the suction for a predetermined time after printing is completed. The method is characterized in that a fan is rotated to hold the media piece cut by the cutter.

[0007] With this configuration, since the cut media piece after printing is held on the platen for a predetermined time, the risk of contamination of the undried image is reduced.

Preferably, during the ink drying period after the printing and the cutting are completed, the medium piece is suction-held on the platen by the suction fan. Execute the initial operation for printing. Thereby, the throughput can be improved.

Immediately before the start of the next printing, the rotation of the suction fan may be stopped once, and the held medium piece may be discharged from the platen. With this configuration,
The cut media piece is held on the platen only by suction of the suction fan, and is discharged out of the apparatus by gravity when the suction is stopped.

[0010] Preferably, a media sensor for detecting the media piece is provided at a holding position of the media piece after printing and cutting of the media piece, and the control means controls the media by the media sensor during the drying period. When the detection is stopped, the rotation of the suction fan is temporarily stopped even before the ink drying time has elapsed, and the process proceeds to the next printing operation. This makes it possible to reduce the standby time when the user removes the media piece from the platen before the elapse of the ink drying time.

More specifically, a means for measuring a required ink drying time after the printing and cutting of the medium piece is completed, a time required for an initial operation at the start of the next printing (hereinafter, an initial operation time), Means for comparing the remaining time of the ink drying time with the remaining time, the initial operation is suppressed until the remaining time is equal to or shorter than the initial operation time, and the rotation of the suction fan is continued. When the time becomes equal to or shorter than the initial operation time, the initial operation is started and the rotation of the suction fan is temporarily stopped.

Alternatively, the control means includes means for measuring a required ink drying time after the printing and cutting of the medium piece, and after the printing and cutting of the medium piece, initials for the next printing. The operation is started and the rotation of the suction fan is continued until the ink drying time elapses, and the rotation of the suction fan is temporarily stopped when the ink drying time elapses.

[0013] The control means may change the drying time of the ink using at least one of a type of a medium to be used, an image data amount, a printing method, and an ambient temperature as parameters. This allows for non-uniform ink drying times depending on the situation

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

FIG. 1 is a view showing the appearance of an ink jet recording apparatus (here, an ink jet plotter) according to the present invention. This figure shows a state in which the cover 11 is opened and the internal carriage 12 is visible. The roll paper pulled out from the roll housed therein passes through an internal transport path, on which an image is printed by a print head mounted on the carriage 12, and then cut and discharged from the front of the apparatus. In the example shown in the figure, an operation unit 13 is provided on the front right side of the apparatus, where the user inputs instructions to the apparatus and displays information from the apparatus to the user.

FIG. 4 is a block diagram showing a hardware configuration of the ink jet recording apparatus according to the present embodiment.

The ink jet recording apparatus 100 receives an image signal from an external host computer 24 and prints it. The inkjet recording apparatus 100 includes a control unit 20
Controls the carriage motor 34 for driving the carriage on which the head 32 is mounted, and the paper transport motor 35
While controlling the ejection of ink droplets from the inkjet head 32 via the head driver 31. Also,
The control unit 20 includes a thermistor (temperature detecting element) 25 for detecting the temperature inside the apparatus, a media sensor 203 for detecting that the roll paper (media) 202 has been set on the platen 201, and a medium present at a holding position to be described later. While controlling the suction fan 23 for sucking the roll paper 202 onto the platen 201 in order to prevent the roll paper 202 from floating and cockling on the platen 201 while receiving the output of the media sensor 39 for detecting that 205
Of the recovery system unit 39 that performs the ink suction operation, the wiper operation, and the preliminary ejection operation of.

The control unit 20 has a CPU for controlling the entire apparatus.
21, a timer 22 for measuring the ink drying time, and driver ICs 26 and 2 for controlling the carriage motor 34 and the paper transport motor 35 under the control of the CPU 21, respectively.
7 inclusive.

FIG. 2 is a side sectional view of the ink jet recording apparatus 100. The platen 201 places a roll paper 202 as a recording material (media) on the upper surface. CPU2
When the media sensor 203 detects that the roll paper 202 has been pulled out of the roll 211 and set on the platen 201, the suction fan 204 is rotated and the suction hole 2 of the medium provided on the platen 201 is rotated.
08, the roll paper 202 is sucked onto the platen. The roll 211 is held on the back of the apparatus by a spool (described later).

The roll paper 202 includes a grid roller 206
Is driven and conveyed by the pinch roller 207 to move on the platen 201. Above the platen 201, for example, two mutually parallel guide shafts are installed in parallel with the platen 201. A carriage is attached to the guide shaft so as to be reciprocally movable via a slide bearing so that the carriage can be moved in parallel along the guide shaft. This carriage has
A head 205 for discharging ink is mounted. The carriage is operated by a carriage motor (34 in FIG. 4) and a belt (not shown) under the control of the control unit 20, and reciprocates the mounted head 205 in parallel with the guide shaft. The recovery system unit 37 is located at a retracted position outside the image forming area at one end of the movable range of the carriage.
Is provided.

In such a configuration, the head 205 moves left and right along the guide shaft together with the carriage. At this time, ink is ejected from nozzles (not shown) to form an image corresponding to the nozzle width. Next, roll paper 202
Is transported by the nozzle width by the grid roller 206 and the pinch roller 207. Image formation is performed by repeating this.

After the formation of the image, the roll paper 202 is cut to a predetermined length by moving the cutter 301 along the cutter groove 209 as shown in FIG.
The cutter 301 is mounted on a carriage, and the blade portion is pulled out by moving the carriage to a cutter pull-out position (not shown). Further, the roll paper 202 can be cut by moving the carriage with the blade portion pulled out.

When the roll paper 202 is cut by the cutter 301, a portion where printing is completed (hereinafter, a print cut paper piece or a medium piece) 302 is separated from the roll paper 202 before printing. By sucking the print cut paper piece 302, the print cut paper piece 302 is held for a time necessary for drying the ink (ink drying period), and the image is protected.

After the elapse of the drying time, the rotation of the suction fan 204 is stopped, that is, the suction of the print cut paper piece 302 is completed, and the print cut paper piece 302 is discharged out of the apparatus (dropped by gravity).

Print cut paper piece 302 for drying ink
The CPU 21 determines whether or not the print cut sheet piece 302 exists at the holding position for drying the ink by the sensor 39 provided in the vicinity of the holding position. The sensor 39 is used when performing continuous printing of a plurality of pages. In the case where printing is continuously performed on a plurality of pages, the print cut paper piece 30 waiting at the ink drying holding position after cutting on the platen is used.
2 is detected, the remaining time of the drying time of the print cut sheet 302 and the initial operation (for example, a wiper operation for the print head,
The CPU 21 compares the time required for the preliminary ejection operation, the positioning of the leading edge of the roll paper, etc.), and starts the initial operation when the time required for the initial operation of the next print becomes longer, and By turning off the suction fan 204, the holding of the print cut sheet piece 302 at the holding position is released, and the print cut sheet piece 302 is discharged out of the apparatus.
Thus, the time point at which the initial operation ends and the time point at which the ink drying time elapses substantially coincide with each other. Since the printing operation is not performed during the initial operation, the next roll paper is prevented from running on the undried print cut sheet piece 302. Also, since the period of the initial operation cannot be used for printing from the beginning, by overlapping this period with the ink drying time, it is possible to shift to the next printing operation immediately after the elapse of the ink drying time or at an earlier time. Can be improved.

Referring to FIG. 5, a specific processing flow of the printing operation in the present embodiment will be described. This process is based on the CP
This is executed by U21.

First, a medium is set (S1).
1) Next, image data to be printed (which may include text) is received (S12), and an initial operation is performed (S13). As described above, the initial operation includes a wiper operation for the print head, a preliminary ejection operation, positioning of the leading end of roll paper, and the like. Next, the suction fan is turned on (S14), and the printing operation is started (S15). After the printing operation is completed, the medium is cut at a predetermined length (S1).
6). At this time or at the end of the printing operation, the timer 22 for counting the ink drying time is started. Therefore, until the drying time of the ink of the image just printed elapses (S1
7, No), unless there is the next print data (S20, N
o), stand by, and when the drying time has elapsed, the suction fan is turned off to open the cut piece of paper (S18). Note that the drying time can be predicted by the CPU 21 based on what kind of image is printed by what kind of printing method as described later.

If there is data to be printed next (S1)
9) Return to receiving data (S12). If the media sensor 39 is off in step S17, the process proceeds to S18. This corresponds to a case where the cut sheet piece is not present at the holding position due to the user picking up the cut sheet piece from the holding position or the like. In such a case, it is not necessary to wait for the elapse of the drying time. It is.

If "next data exists" in step S20, the time required for the next initial operation is compared with the estimated remaining time of the drying time (S21). Since the type of the initial operation performed here is known by the CPU 21, the time required for the type can be predicted. As long as the initial time is longer than the remaining time of the drying time, the apparatus waits as it is. When they match or the initial time is shorter, data is accepted (S22), and the initial operation is started (S2).
3). Also in step S21, the media sensor 39
Is monitored, and if the media sensor 39 is off,
Move to step S22. At the end of the initial operation, the remaining time of the drying time is almost zero. Then, the suction fan is turned off (S24), and the cut piece of paper is opened. Thereafter, the process returns to step S14, where the suction fan is turned on again (S14), and the next printing operation is performed (S15).

Note that, as shown in FIG.
In the case of "there is next data", the data may be immediately received (S31) and the initial operation (S32) may be started. Thereafter, it is checked whether or not the remaining time of the drying time is 0 (S33). If the remaining time is not 0, it is waited until the remaining time becomes 0 and the fan is turned off (S2).
4). Other operations in the process of FIG. 6 are the same as those in the case of FIG. In FIG. 6, the initial operation (S32) is started after the data reception (S31), but both operations may be started simultaneously in parallel.

In the processing flow of FIG. 5, "there is next data"
In the case of, as shown in FIG.
0), the initial operation is started at a time point t1 at which a time (initial operation time) Ti required for the initial operation is inversely calculated from a lapse of a time Td required for ink drying (ink drying time). . by this,
As described above, when the initial operation is completed, the ink is also dry.

On the other hand, in the processing flow of FIG.
As shown in (2), in the case of "there is next data", the initial operation is started immediately upon receipt of the data, and when the time Td required for ink drying has elapsed, the suction fan is turned off and the operation proceeds to the next printing operation. In FIG. 9, the initial operation time Ti
Shows an example in which the elapsed time t4 is earlier than the elapsed time t5 of the ink drying time Td. However, even in the opposite case, the remaining time of the drying time becomes 0 at the elapsed time t5 of the ink drying time Td, and the suction fan Proceed to the off step.

In each of the processes shown in FIGS. 5 and 6, instead of starting the initial operation for the next printing after the elapse of the ink drying time Td, the initial operation is started at an early point in time and the initial operation time is reduced. The feature is that it overlaps at least a part of the ink drying time.

Incidentally, the ink drying time varies depending on the type of roll paper 202 used, as shown in FIG. The CPU 21 can estimate the ink drying time (the time required for drying the ink after printing is completed) based on the type of the roll paper 202 set by the user using the operation panel, the driver, or the like.

Further, as shown in FIG. 11, the ink drying time varies depending on the print duty, the number of print passes (at the time of multi-pass), a printing method such as bidirectional / one-way printing, and the like. In FIG. 11, the horizontal axis represents the drying time, the left vertical axis represents the printing duty, and the right vertical axis represents the printing mode (printing time). The printing time on the right vertical axis is 100 for one-pass bidirectional printing.
Indicates the relative printing time when. As can be seen from this figure, the ink drying time increases in proportion to the print duty. The ink drying time is 1 pass bidirectional → 1 pass unidirectional → 2 pass unidirectional → 4 pass unidirectional → 6
The ink drying time decreases in the order of one pass. This is because, as the number of passes increases, the printing time increases, and as a result, the drying of the ink proceeds as needed during printing,
In addition, the increase in the number of passes causes a reduction in the amount of ink ejected in one scan of the head. Since these printing methods are also known by the CPU 21 in advance, it is possible to predict the ink drying time.

In addition, the ink drying time varies depending on the amount of image data (ink ejection amount) sent from the host computer and the ambient temperature. These can be recognized by the CPU 21 based on the image data sent from the host computer and the thermistor 25 provided in the main body. Based on such various factors, the CPU 21 can predict an appropriate drying time by using a data table (not shown) or the like.

Although the preferred embodiment of the present invention has been described above, various modifications and changes can be made.

[0037]

According to the present invention, in the ink jet recording apparatus, the time until the next printing is started can be shortened and the substantial throughput can be improved without damaging the printed image.

[0038]

[Brief description of the drawings]

FIG. 1 is a view showing the appearance of an ink jet recording apparatus (ink jet plotter) according to the present invention.

FIG. 2 is a side sectional view of the ink jet recording apparatus shown in FIG.

FIG. 3 is a diagram illustrating a state after the roll paper is cut in the inkjet recording apparatus illustrated in FIG. 1;

FIG. 4 is a block diagram illustrating a hardware configuration of the inkjet recording apparatus illustrated in FIG.

FIG. 5 is a flowchart illustrating a specific processing flow of a printing operation according to the embodiment of the present invention.

FIG. 6 is a flowchart illustrating another specific processing flow of a printing operation according to the embodiment of the present invention.

FIG. 7 is a flowchart showing a processing flow of a printing operation in a conventional inkjet plotter.

FIG. 8 is an explanatory diagram of an apparatus operation corresponding to the processing flow of FIG. 6;

FIG. 9 is an explanatory diagram of an apparatus operation corresponding to the processing flow of FIG. 6;

FIG. 10 is a bar graph showing a change in ink drying time depending on the type of roll paper used.

FIG. 11 is a line graph showing a change in ink drying time depending on a print duty, the number of print passes (at the time of multi-pass), a printing method such as bidirectional / one-way printing, and the like.

[Explanation of symbols]

11 ... cover, 12 ... carriage, 13 ... operation panel,
39, 203: media sensor, 201: platen, 2
02: roll paper, 204: suction fan, 205: head, 206: grid roller, 207: pinch roller,
208: suction hole, 209: cutter groove, 301: cutter, 302: print cut paper piece.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C056 EA01 EB14 EB38 EC14 EC36 HA29 HA30 2C058 AB08 AC07 AD01 AE04 AE09 AF06 AF20 AF51 GB01 GB12 GB14 GB30 GB47 GB49 GE24 LA03 LA07 LA14 LB06 LB17 LB42 LC11 2C060 BA05 BC12 BC03 BC03 BC03 BC71 BC83 BC84 BC96 3F103 BC02 BC05 BC10

Claims (7)

[Claims] 1. A medium conveying means for conveying a medium on a platen, a printing means for performing printing by discharging ink droplets on the medium to be conveyed, and a medium on a platen through a medium suction hole provided in the platen. A media suction fan for sucking the media, a cutter for cutting the printed media, and control means for controlling the media suction fan. Provided on both the upstream side and the downstream side, the control means rotates the suction fan during printing, rotates the suction fan for a predetermined time after printing is completed, and controls the medium cut by the cutter. An ink jet recording apparatus characterized by holding a piece. 2. During the ink drying period after completion of printing and cutting, the medium piece is sucked and held on a platen by the suction fan, and the next printing is performed while the ink printed on the medium piece is being dried. 2. The ink jet recording apparatus according to claim 1, wherein an initial operation is performed. 3. The ink jet recording according to claim 1, wherein the rotation of the suction fan is stopped once immediately before the next printing is started, and the held medium piece is discharged from a platen. apparatus. 4. A media sensor for detecting the media piece is provided at a holding position of the media piece after printing and cutting of the media piece, and the control means detects the media by the media sensor during the drying period. 3. The ink jet recording apparatus according to claim 2, wherein when the printing is stopped, the rotation of the suction fan is temporarily stopped even during the ink drying period to shift to a next printing operation. 5. The control means includes means for measuring a required ink drying time after printing and cutting of the medium piece, and a time required for an initial operation at the start of the next printing (hereinafter, an initial operation time). Means for comparing the remaining time of the ink drying time with the remaining time, wherein the initial operation is suppressed and the rotation of the suction fan is continued until the remaining time is equal to or shorter than the initial operation time, and the remaining time is reduced. 3. The ink jet recording apparatus according to claim 2, wherein the initial operation is started and the rotation of the suction fan is temporarily stopped when the time becomes equal to or shorter than the initial operation time. 6. The control means includes means for measuring a required ink drying time after the printing and cutting of the medium piece, and after the printing and cutting of the medium piece,
Starting the initial operation for the next printing and continuing the rotation of the suction fan until the ink drying time elapses, and temporarily stopping the rotation of the suction fan when the ink drying time elapses. The ink jet recording apparatus according to claim 2, wherein 7. The control means sets the ink drying time to
The type of media used, the amount of image data, the printing method,
7. The ink jet recording apparatus according to claim 2, wherein at least one of the ambient temperatures is changed as a parameter.