JP4192928B2 - Tilt detection method and printing method - Google Patents

Description

  The present invention relates to a tilt detection method and a printing method.

A color inkjet printer, which is a typical printing apparatus, is already well known. This color ink jet printer includes an ink jet print head that ejects ink from nozzles, and is configured to record images, characters, and the like by landing ink droplets on printing paper as an example of a printing medium. Yes.
The print head is supported by a carriage, which is an example of a movable member that includes the print head in a state where the nozzle surface on which the nozzles are formed is opposed to the print paper, and is moved along the guide member. The ink is ejected in synchronization with the main scanning.
In recent years, color ink jet printers capable of so-called borderless printing, which performs printing on the entire surface of printing paper, are gaining popularity for the reason that an output result of the same image as a photograph can be obtained. By borderless printing, for example, it is possible to print by ejecting ink without margins on the four edges of the printing paper.

  An object of the present invention is to realize an inclination detection method, a printing method, a program, and a computer system for detecting the inclination of a print sheet when the print sheet is bent and fed.

The main invention is a print head movable in the main scanning direction, a printing medium feeding means for feeding the printing medium, and movable in the main scanning direction, and can detect the presence or absence of the printing medium. A tilt detecting method for detecting the tilt of the printing medium by a printing device that discharges ink from the print head and prints on the printing medium. Positioning at a first position in a scanning direction, feeding the printing medium by the printing medium feeding means, detecting a leading end of the printing medium by the sensor at the first position, A step of moving the sensor to a temporary position different from the first position; a step of detecting the presence or absence of the printing medium by the sensor at the temporary position; and the presence of the printing medium at the temporary position. Moving the sensor to a second position opposite to the temporary position when viewed from the first position, feeding the print medium by the print medium feeding means, and the sensor. Detecting the leading edge of the substrate at the second position, and determining the inclination of the substrate based on the detection result of the leading edge at the first position and the second position; , a tilt-out detecting how having a, the case where it is detected by the sensor and is not the medium to be printed at the temporary position, without moving the sensor to said second position from said temporary position, wherein The printing medium feeding means feeds the printing medium, the leading end of the printing medium is detected by the sensor at a predetermined position on the same side as the temporary position when viewed from the first position, and the first position and the first position Predetermined Based on the leading edge of the detection result of the position, the is the slope detection method characterized by determining the inclination of the printing substrate.

  Other features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

=== Summary of disclosure ===
At least the following will be made clear by the description of the present specification and the accompanying drawings.

In a printing apparatus that has a print head movable in the main scanning direction and a printing medium feeding means for feeding the printing medium, and performs printing on the printing medium by discharging ink from the printing head, The leading edge that is fed in advance by the printing medium feeding means among the edges of the printing medium is detected at a plurality of points to determine the inclination of the printing medium, and according to the obtained inclination, A printing apparatus characterized by changing a start position and / or an end position at which ink is ejected from the print head moving in the scanning direction.
The leading edge that is fed in advance by the printing medium feeding means among the edges of the printing medium is detected at a plurality of points to determine the inclination of the printing medium, and according to the obtained inclination, By changing the start position and / or the end position at which ink is ejected from the print head moving in the scanning direction, the ink consumption can be reduced.

Moreover, it is good also as printing for the whole surface of the said to-be-printed body.
In the case of borderless printing, since the printing is performed also on the edge of the printing paper, the merit by the above means becomes larger.

A light emitting unit for emitting light; and a light receiving sensor for receiving the light that moves in the main scanning direction in accordance with the movement of the light emitting unit in the main scanning direction. The change in the output value of the light receiving sensor caused by blocking the light emitted by the light emitting means may be detected a plurality of times by changing the position of the light emitting means to obtain the inclination of the printing medium.
In this way, the position of the leading end can be easily specified.

Further, a change in the output value due to the leading end of the printing medium being blocked by the light at a first position and a second position that are different from each other in the main scanning direction is detected from the first position to the second position. On the basis of the distance in the main scanning direction and the feed amount of the printing medium from when the change in the output value is detected at the first position to when the change in the output value is detected at the second position, It is good also as calculating | requiring the inclination of a to-be-printed body.
In this way, the number of times the change in the output value of the light receiving sensor is detected can be minimized, and the procedure can be simplified.

Further, the output value of the light receiving sensor is obtained by stopping the printing medium and moving the light emitting means in the main scanning direction so that the light emitted by the light emitting means blocks the edge of the printing medium. Is detected, the position of the edge is specified, and the start position and / or the end position at which ink is ejected from the print head moving in the main scanning direction is changed according to the inclination and the position of the edge. It is also possible to make it.
In this way, since more information for determining an appropriate start position or end position for ejecting ink from the print head moving in the main scanning direction is increased, the appropriate start position or end position is accurately determined. it can.

Further, the change in the output value of the light receiving sensor due to the light emitted by the light emitting means blocking the end of the printing medium is detected twice, the positions of the two ends are specified, and the inclination and The start position or the end position or both may be changed according to the positions of the two ends.
In this way, since more information for determining an appropriate start position or end position for ejecting ink from the print head moving in the main scanning direction is increased, the appropriate start position or end position can be determined more accurately. Can be determined.

The light emitting means and the light receiving sensor may be provided on a moving member that includes the print head and is movable in the main scanning direction.
In this way, there is a merit that the moving mechanism of the moving member, the light emitting means and the light receiving sensor can be shared.

In addition, after detecting the change in the output value of the light receiving sensor due to the movement of the moving member in the main scanning direction and the light emitted by the light emitting means blocking the edge of the printing medium, the detection is performed. Based on this, it is possible to change the start position and / or the end position at which ink is ejected from the print head that moves in the main scanning direction when the moving member is moved again in the main scanning direction.
In this way, there is a merit that it is possible to avoid the inconvenience of having to start discharging ink in advance for some of the nozzles of the print head regardless of the presence or absence of the detection.

A print head movable in the main scanning direction; and a print medium feeding means for feeding the print medium, and ejects ink from the print head to cover the entire surface of the print medium. A printing apparatus for performing printing, comprising: a light emitting means for emitting light; and a light receiving sensor for receiving the light moving in the main scanning direction according to the movement of the light emitting means in the main scanning direction, The light emitting means and the light receiving sensor are provided on a moving member that is provided with a print head and is movable in the main scanning direction. The first and second positions are different from each other in the main scanning direction. Among these, the leading end that is sent in advance by the printing medium feeding means detects a change in the output value of the light receiving sensor due to blocking the light emitted by the positioned light emitting means, and from the first position Said Based on the distance in the main scanning direction to the position and the feed amount of the printing medium from when the change in the output value is detected at the first position until the change in the output value is detected at the second position The inclination of the printing medium is obtained, the printing medium is stopped, and the moving member is moved in the main scanning direction, and the light emitted by the light emitting means blocks the edge of the printing medium. The change in the output value of the light receiving sensor is detected twice, the positions of the two ends are specified, and the moving member is moved again in the main scanning direction according to the inclination and the positions of the two ends. A printing apparatus that changes a start position and / or an end position at which ink is ejected from the print head that moves in the main scanning direction.
In this way, the effects of the present invention can be achieved most effectively because all the effects described above can be achieved.

A printing apparatus that has a print head movable in the main scanning direction and a printing medium feeding means for feeding the printing medium, and discharges ink from the printing head to perform printing on the printing medium. In the printing method according to the present invention, the step of detecting the leading edge of the edge of the substrate to be printed preceding by the substrate feeding means at a plurality of points to determine the inclination of the substrate to be obtained is obtained. Changing a start position and / or an end position at which ink is ejected from the print head moving in the main scanning direction in accordance with the inclination.
The leading edge that is fed in advance by the printing medium feeding means among the edges of the printing medium is detected at a plurality of points to determine the inclination of the printing medium, and according to the obtained inclination, By changing the start position and / or the end position at which ink is ejected from the print head moving in the scanning direction, the ink consumption can be reduced.
It is also possible to realize a computer program for causing a printing apparatus to execute the above method that achieves the above effect of reducing the ink consumption.

In addition, a computer main body, a display device connectable to the computer main body, and a printing device connectable to the computer main body, the print head being movable in the main scanning direction, and the printing medium feed for feeding the printing medium And a printing apparatus that discharges ink from the print head and prints on the printing medium, and is fed in advance by the printing medium feeding means at an end of the printing medium. The leading edge is detected at a plurality of points to determine the inclination of the printing medium, and the start position or the end position at which ink is ejected from the print head moving in the main scanning direction according to the determined inclination, or the position A computer system comprising a printing apparatus that changes both.
The computer system realized in this way is a system superior to the conventional system as a whole system.

=== Example of Overall Configuration of Apparatus ===
FIG. 1 is a block diagram showing a configuration of a printing system as an example of the present invention. This printing system includes a computer 90 and a color inkjet printer 20 as an example of a printing apparatus. The printing system including the color inkjet printer 20 and the computer 90 can also be called a “printing apparatus” in a broad sense. Although not shown, from the computer 90, the color inkjet printer 20, a display device such as a CRT 21 or a liquid crystal display device, an input device such as a keyboard or a mouse, a drive device such as a flexible drive device or a CD-ROM drive device, or the like. A computer system has been built.

  In the computer 90, an application program 95 operates under a predetermined operating system. A video driver 91 and a printer driver 96 are incorporated in the operating system, and print data PD to be transferred to the color inkjet printer 20 is output from the application program 95 via these drivers. The application program 95 that performs image retouching or the like performs desired processing on the image to be processed, and displays an image on the CRT 21 via the video driver 91.

  When the application program 95 issues a print command, the printer driver 96 of the computer 90 receives the image data from the application program 95 and converts it into print data PD to be supplied to the color inkjet printer 20. The printer driver 96 includes a resolution conversion module 97, a color conversion module 98, a halftone module 99, a rasterizer 100, a user interface display module 101, a UI printer interface module 102, and a color conversion lookup table LUT. And are provided.

  The resolution conversion module 97 plays a role of converting the resolution of the color image data formed by the application program 95 into the print resolution. The image data thus converted in resolution is still image information composed of three color components of RGB. The color conversion module 98 converts RGB image data into multi-gradation data of a plurality of ink colors that can be used by the color inkjet printer 20 for each pixel while referring to the color conversion lookup table LUT.

  The color-converted multi-gradation data has, for example, 256 gradation values. The halftone module 99 performs so-called halftone processing to generate halftone image data. The halftone image data is rearranged in the order of data to be transferred to the color inkjet printer 20 by the rasterizer 100, and is output as final print data PD. The print data PD includes raster data indicating the dot formation state during each main scan and data indicating the sub-scan feed amount.

  The user interface display module 101 has a function of displaying various user interface windows related to printing, and a function of receiving user input in these windows.

  The UI printer interface module 102 has a function of interfacing between a user interface (UI) and a color inkjet printer. Interpret the command instructed by the user through the user interface and send various commands COM to the color inkjet printer, or conversely interpret the command COM received from the color inkjet printer and perform various displays on the user interface .

  The printer driver 96 realizes a function of transmitting / receiving various commands COM, a function of supplying print data PD to the color inkjet printer 20, and the like. A program for realizing the function of the printer driver 96 is supplied in a form recorded on a computer-readable recording medium. Such recording media include flexible disks, CD-ROMs, magneto-optical disks, IC cards, ROM cartridges, punch cards, printed matter on which codes such as bar codes are printed, computer internal storage devices (such as RAM and ROM). A variety of computer-readable media such as a memory) and an external storage device can be used. It is also possible to download such a computer program to the computer 90 via the Internet.

  FIG. 2 is a schematic perspective view illustrating an example of a main configuration of the color inkjet printer 20. The color inkjet printer 20 includes a paper stacker 22, a paper feed roller 24 driven by a step motor (not shown), a platen 26, and a carriage as an example of a movable moving member that includes a print head for forming dots. 28, a carriage motor 30, a traction belt 32 driven by the carriage motor 30, and a guide rail 34 for the carriage 28. In addition, a print head 36 having a large number of nozzles and a reflective optical sensor 29 described in detail later are mounted on the carriage 28.

  The printing paper P is taken up by the paper feeding roller 24 from the paper stacker 22 and fed on the surface of the platen 26 in the paper feeding direction (hereinafter also referred to as sub-scanning direction). The carriage 28 is pulled by a pulling belt 32 driven by a carriage motor 30 and moves in the main scanning direction along the guide rail 34. The main scanning direction means two directions perpendicular to the sub-scanning direction as shown in the figure. The paper feeding roller 24 also performs a paper feeding operation for supplying the printing paper P to the color ink jet printer 20 and a paper discharging operation for discharging the printing paper P from the color ink jet printer 20.

=== Configuration Example of Reflective Optical Sensor ===
FIG. 3 is a schematic diagram for explaining an example of the reflective optical sensor 29. The reflective optical sensor 29 is attached to the carriage 28, and includes a light emitting unit 38 as an example of a light emitting unit including, for example, a light emitting diode, and a light receiving unit 40 as an example of a light receiving sensor including, for example, a phototransistor. . Light emitted from the light emitting unit 38, that is, incident light, is reflected by the platen 26 when the printing paper P is not in the direction of the printing paper P or emitted light, and the reflected light is received by the light receiving unit 40, and is electrically Converted to a signal. And the magnitude | size of an electrical signal is measured as an output value of the light receiving sensor according to the intensity of the received reflected light.

  In the above description, as shown in the drawing, the light emitting unit 38 and the light receiving unit 40 are integrated to form a device called the reflective optical sensor 29. However, like the light emitting device and the light receiving device, respectively. A separate device may be configured.

  In the above, in order to obtain the intensity of the received reflected light, the magnitude of the electric signal is measured after converting the reflected light into an electric signal. However, the present invention is not limited to this. It is only necessary to measure the output value of the light receiving sensor according to the intensity of the reflected light.

=== Example of configuration around carriage ===
Next, the configuration around the carriage will be described. FIG. 4 is a diagram showing a configuration around the carriage 28 of the inkjet printer.

  The ink jet printer shown in FIG. 4 has a paper feed motor (hereinafter also referred to as a PF motor) 31 that feeds paper as an example of a printing medium feed means, and a print head 36 that ejects ink onto the printing paper P. A carriage 28 driven in the main scanning direction, a carriage motor (hereinafter also referred to as a CR motor) 30 for driving the carriage 28, a linear encoder 11 fixed to the carriage 28, and slits are formed at predetermined intervals. The linear encoder code plate 12, the rotary encoder 13 (not shown) for the PF motor 31, the platen 26 that supports the printing paper P, and the paper feed roller that is driven by the PF motor 31 to transport the printing paper P 24, a pulley 25 attached to the rotating shaft of the CR motor 30, and a traction belt driven by the pulley 25 And a 2.

  Next, the linear encoder 11 and the rotary encoder 13 will be described. FIG. 5 is an explanatory diagram schematically showing the configuration of the linear encoder 11 attached to the carriage 28.

  The linear encoder 11 shown in FIG. 5 includes a light emitting diode 11a, a collimator lens 11b, and a detection processing unit 11c. The detection processing unit 11c includes a plurality of (for example, four) photodiodes 11d, a signal processing circuit 11e, and, for example, two comparators 11fA and 11fB.

  When the voltage VCC is applied to both ends of the light emitting diode 11a through a resistor, light is emitted from the light emitting diode 11a. This light is condensed into parallel light by the collimator lens 11 b and passes through the linear encoder code plate 12. The linear encoder code plate 12 is provided with slits at predetermined intervals (for example, 1/180 inch (1 inch = 2.54 cm)).

  The parallel light that has passed through the linear encoder code plate 12 passes through a fixed slit (not shown), enters each photodiode 11d, and is converted into an electrical signal. The electric signals output from the four photodiodes 11d are subjected to signal processing in the signal processing circuit 11e, the signals output from the signal processing circuit 11e are compared in the comparators 11fA and 11fB, and the comparison result is output as a pulse. The pulses ENC-A and ENC-B output from the comparators 11fA and 11fB are the outputs of the linear encoder 11.

  FIG. 6 is a timing chart showing waveforms of two output signals of the linear encoder 11 at the time of forward rotation and reverse rotation of the CR motor.

  As shown in FIGS. 6 (a) and 6 (b), the pulse ENC-A and the pulse ENC-B differ in phase by 90 degrees in both cases of CR motor forward rotation and reverse rotation. When the CR motor 30 is rotating forward, that is, when the carriage 28 is moving in the main scanning direction, the pulse ENC-A is 90 degrees from the pulse ENC-B, as shown in FIG. When the phase is advanced by the time and the CR motor 30 is reversely rotated, the phase of the pulse ENC-A is delayed by 90 degrees from the pulse ENC-B, as shown in FIG. One cycle T of the pulse ENC-A and the pulse ENC-B is equal to the time during which the carriage 28 moves through the slit interval of the linear encoder code plate 12.

  Then, the rising edge and the rising edge of each of the output pulses ENC-A and ENC-B of the linear encoder 11 are detected, the number of detected edges is counted, and the rotational position of the CR motor 30 is based on the counted value. Is calculated. This count is incremented by “+1” when one edge is detected when the CR motor 30 is rotating forward, and is “−1” when one edge is detected when the CR motor 30 is rotating in the reverse direction. Is added. The period of each of the pulses ENC-A and ENC-B is the time from when a slit passes through the linear encoder 11 until the next slit passes through the linear encoder 11 of the linear encoder code plate 12. The pulse ENC-A and the pulse ENC-B are different in phase by 90 degrees. For this reason, the count value “1” of the count corresponds to ¼ of the slit interval of the linear encoder code plate 12. Thus, if the count value is multiplied by ¼ of the slit interval, the movement amount of the CR motor 30 from the rotational position corresponding to the count value “0” can be obtained based on the multiplication value. At this time, the resolution of the linear encoder 11 is ¼ of the slit interval of the linear encoder code plate 12.

  On the other hand, the rotary encoder 13 for the PF motor 31 has the same configuration as the linear encoder 11 except that the rotary encoder code plate 14 is a rotating disk that rotates in accordance with the rotation of the PF motor 31. Two output pulses ENC-A and ENC-B are output, and the movement amount of the PF motor 31 can be obtained based on the outputs.

=== Example of an electrical configuration of a color inkjet printer ===
FIG. 7 is a block diagram illustrating an example of an electrical configuration of the color inkjet printer 20. The color inkjet printer 20 includes a buffer memory 50 that receives a signal supplied from a computer 90, an image buffer 52 that stores print data, a system controller 54 that controls the overall operation of the color inkjet printer 20, and a main memory 56. And an EEPROM 58. The system controller 54 further includes a main scanning drive circuit 61 that drives the carriage motor 30, a sub-scanning drive circuit 62 that drives the paper feed motor 31, a head drive circuit 63 that drives the print head 36, and reflective optics. A reflection type optical sensor control circuit 65 that controls the light emitting unit 38 and the light receiving unit 40 of the sensor 29, the linear encoder 11 described above, and the rotary encoder 13 described above are connected. The reflection type optical sensor control circuit 65 includes an electric signal measurement unit 66 for measuring an electric signal converted from the reflected light received by the light receiving unit 40.

  The print data transferred from the computer 90 is temporarily stored in the buffer memory 50. In the color ink jet printer 20, the system controller 54 reads necessary information from the print data from the buffer memory 50, and based on this information, the system controller 54 sends it to the main scanning drive circuit 61, the sub-scanning drive circuit 62, the head drive circuit 63, and the like. Send a control signal to it.

  The image buffer 52 stores print data of a plurality of color components received by the buffer memory 50. The head drive circuit 63 reads the print data of each color component from the image buffer 52 in accordance with a control signal from the system controller 54 and drives the nozzle array of each color provided in the print head 36 in response to this.

=== Example of print head nozzle arrangement ===
FIG. 8 is an explanatory diagram showing the nozzle arrangement on the lower surface of the print head 36. The print head 36 has a black nozzle row and a color nozzle row arranged on a straight line along the sub-scanning direction. In this specification, the “nozzle row” is also referred to as “nozzle group”.

  The black nozzle row (indicated by white circles) has 180 nozzles # 1 to # 180. These nozzles # 1 to # 180 are arranged at a constant nozzle pitch k · D along the sub-scanning direction. Here, D is the dot pitch in the sub-scanning direction, and k is an integer. The dot pitch D in the sub-scanning direction is equal to the pitch of the main scanning line (raster line). Hereinafter, the integer k representing the nozzle pitch k · D is simply referred to as “nozzle pitch k”. The unit of the nozzle pitch k is “dot”, which means the dot pitch in the sub-scanning direction.

  In the example of FIG. 8, the nozzle pitch k is 4 dots. However, the nozzle pitch k can be set to an arbitrary integer.

The color nozzle array includes a yellow nozzle group Y (indicated by white triangles), a magenta nozzle group M (indicated by white squares), and a cyan nozzle group C (indicated by white rhombuses). In this specification, the nozzle group for chromatic ink is also referred to as a “chromatic nozzle group”. Each chromatic nozzle group has 60 nozzles # 1 to # 60. Further, the nozzle pitch of the chromatic nozzle group is the same as the nozzle pitch k of the black nozzle row. The nozzles of the chromatic color nozzle group are arranged at the same sub-scanning position as the nozzles of the black nozzle row.
During printing, ink droplets are ejected from each nozzle while the print head 36 is moving in the main scanning direction together with the carriage 28. However, depending on the printing method, not all nozzles are always used, and only some nozzles may be used.

=== First Embodiment ===
Next, the first embodiment of the present invention will be described with reference to FIGS. FIG. 9 is a diagram schematically showing the positional relationship among the print head 36, the reflective optical sensor 29, and the printing paper P, and FIG. 10 is a flowchart for explaining the first embodiment.

  First, the user instructs to perform printing in the application program 95 or the like (step S2). When the application program 95 that has received this instruction issues a print command, the printer driver 96 of the computer 90 receives image data from the application program 95, and receives the raster data and the sub data indicating the dot formation state during each main scan. The print data PD including data indicating the scanning feed amount is converted. Further, the printer driver 96 supplies the print data PD to the color inkjet printer 20 together with various commands COM. The color inkjet printer 20 receives these by the buffer memory 50 and then transmits them to the image buffer 52 or the system controller 54.

  Further, the user can instruct the user interface display module 101 to perform the size of the printing paper P or borderless printing. The instruction by the user is received by the user interface display module 101 and sent to the UI printer interface module 102. The UI printer interface module 102 interprets the instructed command and transmits a command COM to the color inkjet printer 20. The color inkjet printer 20 receives the command COM by the buffer memory 50 and then transmits it to the system controller 54.

  Based on the command transmitted to the system controller 54, the color inkjet printer 20 feeds the printing paper P by driving the paper feed motor 31 by the sub-scanning drive circuit 62 (step S4).

  Next, the system controller 54 drives the CR motor 30 by the main scanning drive circuit 61 to move and position the carriage 28 to a predetermined position (hereinafter also referred to as a first position) (step S6). Then, the movement amount from the reference position of the CR motor 30 is obtained based on the output pulse of the linear encoder 11, and the movement amount, in other words, the first position of the carriage 28 is stored (step S8).

  Further, the system controller 54 controls the reflective optical sensor 29 provided in the positioned carriage 28 by the reflective optical sensor control circuit 65, and directs the light emitting unit 38 of the reflective optical sensor 29 toward the platen 26. Light is emitted (step S10).

  When the printing paper P is further fed by the paper feeding motor 31 as shown in FIGS. 9A and 9B, the paper feeding motor is eventually out of the ends of the printing paper P as shown in FIG. 9B. The leading end (hereinafter also referred to as the upper end) sent in advance by 31 blocks the light emitted from the light emitting unit 38 (step S12). At this time, the incident destination of the light emitted from the light emitting unit 38 is changed from the platen 26 to the printing paper P, so that the electric signal that is the output value of the light receiving unit 40 of the reflective optical sensor 29 that has received the reflected light. The size changes. Then, the magnitude of the electrical signal is measured by the electrical signal measuring unit 66 to detect that the upper end of the printing paper P has passed the light.

  At this time, the system controller 54 obtains the movement amount from the reference position of the PF motor 31 based on the output pulse of the rotary encoder 13, and stores the movement amount, in other words, the feed amount of the printing paper P. (Step S14).

  Next, the system controller 54 drives the CR motor 30 by the main scanning drive circuit 61 to move the carriage 28 from the first position to a predetermined position (hereinafter also referred to as a temporary position) (step S16). ). The predetermined position may be either upstream or downstream in the main scanning direction when viewed from the first position. In the present embodiment, as shown in FIGS. 9B and 9C, the carriage 28 is moved and positioned upstream.

  Then, the system controller 54 controls the reflective optical sensor 29 by the reflective optical sensor control circuit 65, receives the reflected light of the light emitted from the light emitting unit 38, and receives the output value. The electric signal measuring unit 66 measures the magnitude of the electric signal. Further, the system controller 54 compares the measured value with a predetermined threshold value, and determines whether or not the light incident destination is the printing paper P (step S18). That is, when the light is incident on the printing paper P and when it is not (that is, the platen 26), the intensity of the reflected light varies depending on the difference in the colors of the two. By comparing the output value of the light receiving sensor corresponding to the intensity of the light with a predetermined threshold value, it is possible to determine whether or not the light incident destination is the printing paper P.

Next, as a result of the determination, when it is determined that the light incident destination is the printing paper P, the system controller 54 drives the CR motor 30 by the main scanning drive circuit 61 to move the carriage 28 to the carriage 28. Positioning is performed by moving from the temporary position to a predetermined position (hereinafter also referred to as a second position) opposite to the temporary position side as viewed from the first position (step S20). On the other hand, when it is determined that the light incident destination is not the printing paper P, the system controller 54 sees the carriage 28 from the first position, that is, a predetermined position on the same side as the temporary position side, that is, the first position. The position is moved to the second position from the temporary position (step S22). Then, the movement amount from the reference position of the CR motor 30 is obtained based on the output pulse of the linear encoder 11, and the movement amount, in other words, the second position of the carriage 28 is stored (step S24).
When it is determined that the light incident destination is not the printing paper P, the temporary position may be set to the second position without moving the carriage 28 from the temporary position to the second position.

  In the present embodiment, as shown in FIG. 9C, it is determined that the light incident destination is the printing paper P. Therefore, the system controller 54 in FIG. 9C and FIG. As shown, the carriage 28 is moved and positioned from the temporary position to a predetermined position (hereinafter also referred to as a second position) opposite to the temporary position side and the first position (step S20).

  Furthermore, when the printing paper P is further fed by the paper feed motor 31 as shown in FIGS. 9D and 9E, the upper end of the printing paper P eventually emits the light emission as shown in FIG. 9E. The light emitted from the unit 38 is blocked (step S26). At this time, the incident destination of the light emitted from the light emitting unit 38 is changed from the platen 26 to the printing paper P, so that the electric signal that is the output value of the light receiving unit 40 of the reflective optical sensor 29 that has received the reflected light. The size changes. Then, the magnitude of the electrical signal is measured by the electrical signal measuring unit 66 to detect that the upper end of the printing paper P has passed the light.

  At this time, the system controller 54 obtains the movement amount from the reference position of the PF motor 31 based on the output pulse of the rotary encoder 13, and stores the movement amount, in other words, the feed amount of the printing paper P. (Step S28).

  Next, the system controller 54 stores the first position of the carriage 28 stored in step S8, the second position of the carriage 28 stored in step S24, the feed amount of the printing paper P stored in step S14, and The inclination of the printing paper P is obtained from the feeding amount of the printing paper P stored in step S28.

  A more detailed description will be given with reference to FIG. FIG. 11 is a diagram for explaining an example of a method for obtaining the inclination of the printing paper P.

  A straight line rising to the right indicated by a solid line in the drawing represents the upper end of the printing paper P. Further, the left end of the straight line shown in the drawing represents the right end (hereinafter also referred to as the upper right end) of the printing paper P, and the right end of the straight line represents the left end of the upper end of the printing paper P. The reason why the left and right sides are reversed with respect to the straight line and the upper end of the printing paper P is that the paper feeding direction is from the upper side to the lower side of the drawing.

  As shown in the figure, the first position stored in step S8 when the first position of the carriage 28 is the point A is a numerical value a. Similarly, the second position stored in step S24 when the second position of the carriage 28 is the point B is set as a numerical value b. For convenience, both the numerical values a and b are values based on the position of the upper right end of the printing paper P in the main scanning direction, but the present invention is not limited to this, and other positions may be used.

  Further, paying attention to the paper feeding direction, since the carriage moves only in the main scanning direction, the difference p between the positions of the points A and B in the figure is the same as the feeding amount of the printing paper P stored in step S14. This represents a difference from the feeding amount of the printing paper P stored in S28. Therefore, the difference p can be obtained from the numerical values stored in step S14 and step S28.

  Next, the inclination of the printing paper P is obtained from the numerical values a, b, and p. As shown in the figure, the inclination is represented by, for example, an angle θ between the main scanning direction and the straight line. As is apparent from the figure, there is a relationship of angle θ = tan−1 (p / (b−a)).

  In this way, the inclination of the printing paper P is obtained from the numerical values stored in steps S8, S14, S24, and S28 (step S30).

Next, as shown in FIGS. 9E and 9F, the system controller 54 drives the CR motor 30 by the main scanning drive circuit 61 to move the carriage 28. Eventually, as shown in FIG. 9F, the edge of the printing paper P blocks the light emitted from the light emitting section 38 (step S32). At this time, since the incident destination of the light emitted from the light emitting unit 38 is changed from the printing paper P to the platen 26, the electric signal that is the output value of the light receiving unit 40 of the reflective optical sensor 29 that has received the reflected light. The size changes. Then, the magnitude of this electric signal is measured by the electric signal measuring unit 66, and it is detected that the edge of the printing paper P has passed the light.
Then, the movement amount from the reference position of the CR motor 30 is obtained based on the output pulse of the linear encoder 11, and the movement amount, in other words, the position of the carriage 28 (hereinafter also referred to as the third position) is stored ( Step S34).

Next, as shown in FIGS. 9 (f) and 9 (g), the system controller 54 drives the CR motor 30 to further move the carriage 28 in order to perform borderless printing on the printing paper P. .
Then, as shown in FIGS. 9 (g) and 9 (h), borderless printing is performed by ejecting ink from the print head 36 while moving the carriage 28 in the main scanning direction (step S38).

  Here, the position where ink ejection starts or ends will be described with reference to FIG. FIG. 12 is an explanatory diagram of positions where ink ejection starts or ends.

The positional relationship among the print head 36, the reflective optical sensor 29, and the printing paper P in FIG. 12 corresponds to that in FIG. While the print head 36 shown on the left side of the figure moves in the main scanning direction, ink is ejected from the nozzles of the print head 36 to perform printing on the printing paper P. The print head 36 is shown on the right side of the figure. To reach the position. The six straight lines drawn on the printing paper P represent a set of dots formed by ejecting ink from the nozzles of the print head 36. The nozzle arrangement is as already described with reference to FIG. 8, but in order to facilitate understanding in FIG. 12, the printing is configured by a group of nozzles and provided with eight nozzles. A head is shown as an example.
In the present embodiment, a method for determining the position at which ink discharge from the nozzle N shown in the drawing among the eight nozzles starts or ends will be described. However, the other nozzles are determined based on the same concept. be able to.

  First, attention is paid to the lower left portion of the printing paper P shown in FIG. As shown in the figure, the distance in the paper feeding direction between the reflective optical sensor 29 and the nozzle N is y1, the inclination of the printing paper P is the angle θ, and the third position C and the edge of the printing paper P move in the main scanning direction. Assuming that the distance in the main scanning direction from the point through which the nozzle N of the print head 36 passes is x1, the relationship x1 = y1 × tan θ is established. Since the distance y1 is known, the distance x1 can be obtained by substituting the inclination of the printing paper P obtained in step S30 for the angle θ.

  Similarly, paying attention to the lower center of the printing paper P shown in FIG. 12, as shown in the figure, the distance in the paper feeding direction between the reflective optical sensor 29 and the nozzle N is y1, and the inclination of the printing paper P is the angle θ. X2 = y1 / tan θ where x2 is the distance in the main scanning direction between the second position B and the point where the nozzle N of the print head 36 moving in the main scanning direction among the ends of the printing paper P passes the second time. The relationship is established. Since the distance y1 is known, the distance x2 can be obtained by substituting the inclination of the printing paper P obtained in step S30 for the angle θ.

  Then, based on the third position C in the main scanning direction stored in step S34 and the x1, the position for starting ink ejection from the nozzle N is determined, and the second main scanning direction stored in step S24. Based on the position B and x2, it is possible to determine the position at which the ink ejection from the nozzle N is to be terminated (step S36).

  That is, the system controller 54 controls the main scanning drive circuit 61 to move the CR motor 30 in the main scanning direction, and controls the head driving circuit 63 to drive the print head 36, and the distance x1 from the third position C. The ejection of ink from the nozzle N is started with a delay, and the ejection of ink from the nozzle N is completed earlier than the second position B by the distance x2 (step S38).

  Further, the movement of the carriage 28 in the main scanning direction from FIG. 9G to FIG. 9H causes the light emitted from the light emitting portion 38 of the reflective optical sensor 29 to block the edge of the printing paper P. Become. That is, the above phenomenon occurs when the positional relationship between the printing paper P and the reflective optical sensor 29 is the relationship shown in FIGS. 9 (f) and 9 (e). At this time, as described above, the magnitude of the electrical signal that is the output value of the light receiving unit 40 of the reflective optical sensor 29 that has received the reflected light changes. Then, the magnitude of the electrical signal is measured by the electrical signal measuring unit 66, and it is detected that the edge of the printing paper P has passed the light (step S38).

  Then, the movement amount from the reference position of the CR motor 30 is obtained based on the output pulse of the linear encoder 11, and the movement amount, in other words, the position of the carriage 28 (hereinafter referred to as the carriage 28 corresponding to FIG. 9 (f)). Is stored as the fourth position, and the position of the carriage 28 corresponding to FIG. 9E is also referred to as the fifth position) (step S40).

Next, as shown in FIGS. 9H and 9I, the system controller 54 drives the CR motor 30 to move the carriage 28 and drives the paper feed motor 31 to perform printing. A predetermined amount of paper P is fed to prepare for the next borderless printing (step S42). At this time, the system controller 54 obtains the movement amount from the reference position of the PF motor 31 based on the output pulse of the rotary encoder 13, and stores the movement amount, in other words, the feed amount of the printing paper P. (Step S44).
Then, as shown in FIGS. 9I and 9J, borderless printing is performed by ejecting ink from the print head 36 while moving the carriage 28 in the main scanning direction (step S48).

  Here, the position where ink ejection starts or ends will be described with reference to FIG. FIG. 13 is an explanatory diagram of positions where ink ejection starts or ends.

  The positional relationship among the print head 36, the reflective optical sensor 29, and the printing paper P in FIG. 13 corresponds to that in FIG. While the print head 36 shown on the left side of the figure moves in the main scanning direction, ink is ejected from the nozzles of the print head 36 to perform printing on the printing paper P. The print head 36 is shown on the right side of the figure. To reach the position. The twelve straight lines drawn on the printing paper P represent a set of dots formed by ejecting ink from the nozzles of the print head 36. Among these, even-numbered straight lines counted from the top in the figure are steps. The odd-numbered straight line is formed in this step.

  In the figure, two reflective optical sensors 29 are shown. The reflective optical sensor 29 indicated by a dotted line on the lower side is a reflective optical sensor before the printing paper P is fed by the predetermined amount. 29 is shown to show the relative position between the paper 29 and the printing paper P. As shown in the figure, the position in the paper feed direction of the reflective optical sensor 29 indicated by the dotted line on the lower side coincides with the position in the paper feed direction of the fourth position D and the fifth position E described above. ing.

The nozzle arrangement is as already described with reference to FIG. 8, but in FIG. 13, for the sake of easy understanding, the printing is composed of a group of nozzles and is provided with eight nozzles. A head is shown as an example.
In the present embodiment, a method for determining the position at which ink discharge from the nozzle N shown in the drawing among the eight nozzles starts or ends will be described. However, the other nozzles are determined based on the same concept. be able to.

  First, attention is paid to the lower left part of the printing paper P shown in FIG. As shown in the figure, the distance in the paper feed direction between the reflective optical sensor 29 indicated by the dotted line on the lower side and the nozzle N is y2, the inclination of the printing paper P is the angle θ, the fourth position D and the printing paper P When the distance in the main scanning direction from the end of the nozzle N of the print head 36 moving in the main scanning direction passes is x3, the relationship x3 = y2 × tan θ is established. Since the distance y2 is equal to the value obtained by subtracting the predetermined paper feed amount of the printing paper P described above from the known distance y1, the distance y2 is obtained by substituting the inclination of the printing paper P obtained in step S30 for the angle θ. x3 can be obtained. The predetermined paper feed amount can be obtained by taking the difference between the numerical values stored in step S28 and step S44.

  Similarly, when attention is paid to the lower center of the printing paper P shown in FIG. 13, as shown in the figure, the distance in the paper feeding direction between the reflective optical sensor 29 and the nozzle N indicated by the dotted line on the lower side is y2, The inclination of the printing paper P is the angle θ, and the distance in the main scanning direction between the fifth position E and the point where the nozzle N of the printing head 36 moving in the main scanning direction among the ends of the printing paper P passes the second time is x4. Then, the relationship x4 = y2 / tan θ is established. Since the distance y2 is equal to the value obtained by subtracting the predetermined paper feed amount of the printing paper P described above from the known distance y1, the distance y2 is obtained by substituting the inclination of the printing paper P obtained in step S30 for the angle θ. x4 can be obtained.

  Then, based on the fourth position D in the main scanning direction stored in step S40 and the x3, the position at which the nozzle N starts to eject ink is determined, and the fifth in the main scanning direction stored in step S40. Based on the position E and the x4, it is possible to determine the position at which the ejection of the ink from the nozzle N is completed (step S46).

  That is, the system controller 54 controls the main scanning drive circuit 61 to move the CR motor 30 in the main scanning direction, and controls the head driving circuit 63 to drive the print head 36, and the distance x3 from the fourth position D. The ejection of ink from the nozzle N is started with a delay, and the ejection of ink from the nozzle N is completed earlier than the fifth position E by the distance x4 (step S48).

Further, the movement of the carriage 28 in the main scanning direction from FIG. 9I to FIG. 9J causes the light emitted from the light emitting portion 38 of the reflective optical sensor 29 to block the edge of the printing paper P. Become. At this time, as described above, the magnitude of the electrical signal that is the output value of the light receiving unit 40 of the reflective optical sensor 29 that has received the reflected light changes. Then, the magnitude of this electrical signal is measured by the electrical signal measuring unit 66, and it is detected that the edge of the printing paper P has passed the light (step S48).
Then, the movement amount from the reference position of the CR motor 30 is obtained based on the output pulse of the linear encoder 11, and the movement amount, in other words, the position of the carriage 28 is stored (step S50).

Next, the system controller 54 drives the CR motor 30 to move the carriage 28 and also drives the paper feed motor 31 to feed the printing paper P by a predetermined amount to prepare for the next borderless printing. . The following procedure is the same as that already described, and the ink discharge start and end positions for each nozzle of the print head 36 are determined based on the position of the carriage 28 stored in step S50 and the predetermined amount. Based on the above, borderless printing is performed on the printing paper P. Then, the borderless printing is completed by repeating this procedure.
Note that a program for performing the above processing is stored in the EEPROM 58, and the program is executed by the system controller 54.

Taking into account that the printing paper is bent (obliquely), prepare print data that is slightly larger than the printing paper, in other words, with some margin compared to the size of the printing paper. In the method of printing on the printing paper based on the print data, there is a possibility that printing is performed in an area other than the printing paper, and there is a problem that ink is consumed wastefully.

  Thus, in this way, the upper end of the printing paper P is detected at a plurality of points to determine the inclination of the printing paper P, and ink is ejected from the print head 36 that moves in the main scanning direction according to the obtained inclination. If the ink consumption is reduced by changing the start position and / or the end position, the above problem can be solved.

  In the above, in step S14 and step S28, the amount of movement of the PF motor 31 from the reference position is obtained, the amount of movement is stored as the amount of feed of the printing paper P, and this difference is stored at the first position of the light receiving sensor. The feed amount of the printing paper from when the change in the output value is detected until the change in the output value of the light receiving sensor is detected at the second position is the reference position when the movement amount of the PF motor 21 is obtained in step S28. May be obtained as the position of the PF motor 31 in step S14. Further, the above-described procedure for obtaining a predetermined paper feed amount from the difference between the numerical values stored at step S28 and step S44, and the above-described procedure for obtaining the distance in the main scanning direction from the difference between numerical values stored at step S8 and step S24. The same is true for the procedure.

  In the above description, the first position, the temporary position, and the second position are set as predetermined positions, but may be arbitrary positions. Further, when the first position and the second position are the predetermined positions, the subsequent procedure for storing the first position and the second position, that is, steps S8 and S24 may be omitted.

  In step S38, the ejection of ink from the nozzle N is started after being delayed by the distance x1 from the third position C, and the ejection of ink from the nozzle N is terminated earlier than the second position B by the distance x2. The ink ejection from the nozzle N is started with a certain margin and delayed by a distance (x1-Δ1) smaller than the distance x1, and the ink from the nozzle N is earlier by a distance (x2-Δ2) smaller than the distance x2. The discharge may be terminated. Similarly, in step S48, ejection of ink from the nozzle N is started with a delay (x3-Δ3) smaller than the distance x3, and ink from the nozzle N is earlier by a distance (x4-Δ4) smaller than the distance x4. It is good also as ending discharge of this.

=== Other Embodiments ===
As described above, the printing apparatus and the like according to the present invention have been described based on one embodiment. However, the above-described embodiment is intended to facilitate understanding of the present invention and is not intended to limit the present invention. Absent. The present invention can be changed and improved without departing from the gist thereof, and the present invention includes the equivalents thereof.

  Moreover, although the printing paper has been described as an example of the printing material, a film, a cloth, a thin metal plate, or the like may be used as the printing material.

  Further, a computer main body, a display device connectable to the computer main body, a printer according to the above-described embodiment connectable to the computer main body, an input device such as a mouse and a keyboard provided as necessary, a flexible disk drive A computer system having a device and a CD-ROM drive device can also be realized, and the computer system realized in this way is an overall system superior to the conventional system.

  The printer according to the above-described embodiment may have a part of functions or mechanisms respectively included in the computer main body, the display device, the input device, the flexible disk drive device, and the CD-ROM drive device. For example, the printer includes an image processing unit that performs image processing, a display unit that performs various displays, and a recording medium attachment / detachment unit for attaching / detaching a recording medium that records image data captured by a digital camera or the like. Also good.

  In the above embodiment, a color inkjet printer has been described. However, the present invention can also be applied to a monochrome inkjet printer.

In the above embodiment, printing is performed on the entire surface of the printing paper P, that is, so-called borderless printing is performed. However, the present invention is not limited to this. Although not the entire surface, the above means exerts an effective effect when printing over a wide range.
However, in the case of borderless printing, since the printing is performed also on the edge of the printing paper, the merit by the above means becomes larger.

Moreover, in the said embodiment, the light emission part 38 for emitting light, The light-receiving part 40 for light-receiving the said light which moves to a main scanning direction according to the movement to the main scanning direction of this light emission part 38, The change in the output value of the light receiving unit 40 caused by blocking the light emitted by the positioned light emitting unit 38 is detected a plurality of times by changing the position of the light emitting unit 38, and the inclination of the printing paper P is provided. However, the present invention is not limited to this.
However, the above embodiment is more preferable in that the upper end position can be easily specified by doing in this way.

In the above embodiment, the first position is detected by detecting a change in the output value of the light receiving unit 40 due to the upper end of the printing paper P blocking the light at the first position and the second position that are different from each other in the main scanning direction. Based on the distance in the main scanning direction from the first position to the second position and the feed amount of the printing medium from when the change in the output value is detected at the first position until the change in the output value is detected at the second position. Thus, although the inclination of the printing paper P is obtained, the present invention is not limited to this.
However, the above embodiment is more preferable in that the number of times of detecting the change in the output value of the light receiving sensor can be minimized and the procedure can be simplified. .

In the above-described embodiment, the light receiving unit is configured such that the printing paper P is stopped and the light emitting unit 38 is moved in the main scanning direction so that the light emitted from the light emitting unit 38 blocks the edge of the printing paper P. 40, a change in the output value of 40 is detected, the position of the edge of the printing paper P is specified, and the start position or the discharge position of the ink from the print head 36 moving in the main scanning direction according to the inclination and the position of the edge The end position or both are changed, but the present invention is not limited to this. For example, the start position or the end position where ink is ejected from the print head 36 that moves in the main scanning direction according to only the tilt. Alternatively, both of them may be changed.
However, by doing so, since more information for determining an appropriate start position or end position for ejecting ink from the print head 36 moving in the main scanning direction is increased, the appropriate start position or end position can be increased. The above embodiment is more preferable in that it can be determined with high accuracy.

Further, in the above embodiment, the change in the output value of the light receiving unit 40 due to the light emitted from the light emitting unit 38 blocking the end of the printing paper P is detected twice, and the positions of the two ends are specified. The start position or the end position or both are changed according to the inclination and the positions of the two ends, but the present invention is not limited to this. For example, the inclination and the two positions are changed. The start position and / or the end position at which ink is ejected from the print head 36 moving in the main scanning direction may be changed only in accordance with the position of one of the ends.
However, by doing so, since more information for determining an appropriate start position or end position for ejecting ink from the print head 36 moving in the main scanning direction is increased, the appropriate start position or end position can be increased. The above embodiment is more preferable in that it can be determined with high accuracy.

In the above embodiment, the light emitting unit 38 and the light receiving unit 40 are provided on the carriage 28 that includes the print head 36 and is movable in the main scanning direction. However, the present invention is not limited to this. For example, the carriage 28, the light emitting unit 38, and the light receiving unit 40 may be configured to be separately movable in the main scanning direction.
However, the above embodiment is preferable in that the moving mechanism of the carriage 28, the light emitting unit 38, and the light receiving unit 40 can be made common by doing in this way.

Further, in the above embodiment, as shown in Step S38 to Step S48, the light receiving unit that moves the carriage 28 in the main scanning direction and blocks the edge of the printing paper P by the light emitted by the light emitting unit 38. After detecting a change in the output value of 40 (step S38), based on this detection, a start position for ejecting ink from the print head 36 that moves in the main scanning direction when the carriage 28 is moved again in the main scanning direction Alternatively, the end position or both are changed (step S48). However, the present invention is not limited to this. For example, in one movement of the carriage 28 in the main scanning direction, the output value of the light receiving unit 40 is changed. , And based on the detection, a start position and / or an end position at which ink is ejected from the print head 36 moving in the main scanning direction is detected. It may be of.
However, in the latter method, when a change in the output value of the light receiving unit 40 is detected, there are cases where some of the nozzles of the print head 36 have already passed through the end of the printing paper P. For this, it is necessary to take measures such as starting ink ejection in advance regardless of the presence or absence of the detection. On the other hand, the method according to the embodiment is more desirable in this respect because there is no such inconvenience.

In the above embodiment, after the change in the output value is detected at the first position, the light emitting unit 38 and the light receiving unit 40 are moved upstream or downstream in the main scanning direction from the first position. When it is determined that the light has been applied to the printing paper P based on the output value of the light receiving unit 40 that has been moved to either side and received the light emitted by the light emitting unit 38, the determination side When the second position is set on the opposite side when viewed from the first position and it is determined that the light is not applied to the printing paper P, the second position is viewed from the determined side and the first position. Although the second position is set on the same side, the present invention is not limited to this. For example, the second position may be set by omitting such a procedure.
However, if the second position is set on the side where the incident light is the printing paper if the light is applied without performing the above procedure, the upper end of the printing paper at the second position is set. In order to block the light, it is necessary to back-feed the printing paper. Therefore, the above embodiment is more desirable in that such inconvenience can be avoided.

  Further, in the above, the output value of the light receiving unit 40 is obtained by stopping the printing paper P and moving the light emitting unit 38 in the main scanning direction so that the light emitted by the light emitting unit 38 blocks the edge of the printing paper P. The position of the edge is detected, the position of the edge is specified, and the start position and / or the end position where ink is ejected from the print head moving in the main scanning direction according to the obtained inclination and the position of the edge However, the position of the end, which is information used for determining an appropriate start position or end position, does not necessarily have to be specified immediately before.

1 is a block diagram illustrating a configuration of a printing system as an example of the present invention. 2 is a schematic perspective view illustrating an example of a main configuration of the color inkjet printer 20. FIG. 4 is a schematic diagram for explaining an example of a reflective optical sensor 29. FIG. FIG. 2 is a diagram illustrating a configuration around a carriage 28 of an inkjet printer. 3 is an explanatory diagram schematically showing a configuration of a linear encoder 11 attached to a carriage 28. FIG. 4 is a timing chart showing waveforms of two output signals of the linear encoder 11 during normal rotation and reverse rotation of a CR motor. 2 is a block diagram illustrating an example of an electrical configuration of the color inkjet printer 20. FIG. 4 is an explanatory diagram showing a nozzle arrangement on the lower surface of the print head. FIG. 3 is a diagram schematically illustrating a positional relationship among the print head 36, the reflective optical sensor 29, and the printing paper P. FIG. It is a flowchart for demonstrating 1st embodiment. 5 is a diagram for explaining an example of a method for obtaining the inclination of the printing paper P. FIG. It is explanatory drawing of the position which starts or complete | finishes discharge of an ink. It is explanatory drawing of the position which starts or complete | finishes discharge of an ink.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Linear encoder 12 Linear encoder code board 13 Rotary encoder 14 Rotary encoder code board 20 Color inkjet printer 21 CRT
DESCRIPTION OF SYMBOLS 22 Paper stacker 24 Paper feed roller 25 Pulley 26 Platen 28 Carriage 29 Reflective optical sensor 30 Carriage motor 31 Paper feed motor 32 Pull belt 34 Guide rail 36 Print head 38 Light emitting part 40 Light receiving part 50 Buffer memory 52 Image buffer 54 System controller 56 Main memory 58 EEPROM
61 Main Scan Drive Circuit 62 Sub Scan Drive Circuit 63 Head Drive Circuit 65 Reflective Optical Sensor Control Circuit 66 Electrical Signal Measuring Unit 90 Computer 91 Video Driver 95 Application Program 96 Printer Driver 97 Resolution Conversion Module 98 Color Conversion Module 99 Halftone Module 100 Rasterizer 101 User interface display module 102 UI printer interface module

Claims (5)

A print head movable in the main scanning direction, a printing medium feeding means for feeding the printing medium, and a sensor capable of moving in the main scanning direction and detecting the presence or absence of the printing medium; An inclination detection method for detecting an inclination of the printing medium by a printing apparatus that prints on the printing medium by discharging ink from the print head,
Positioning the sensor at a first position in the main scanning direction;
Feeding the print medium by the print medium feeding means;
Detecting the leading end of the substrate by the sensor at the first position;
Moving the sensor to a temporary position different from the first position;
Detecting the presence or absence of the substrate by the sensor at the temporary position;
Moving the sensor to a second position opposite to the temporary position when viewed from the first position when the sensor detects that the printing medium is present at the temporary position;
Feeding the print medium by the print medium feeding means;
Detecting the leading end of the substrate by the sensor at the second position;
Obtaining the inclination of the printing material based on the detection result of the leading edge at the first position and the second position;
A tilt-out detection method that have a,
When the sensor detects that the printing medium is not present at the temporary position, the printing medium feeding means feeds the printing medium without moving the sensor from the temporary position to the second position. Based on the detection result of the leading edge at the first position and the predetermined position, the leading edge of the printing medium is detected by the sensor at a predetermined position on the same side as the temporary position when viewed from the first position. To determine the inclination of the substrate.
An inclination detection method characterized by that . The tilt detection method according to claim 1 ,
The inclination detection method, wherein the predetermined position is the temporary position. The tilt detection method according to claim 1 or 2 ,
The distance in the main scanning direction from the first position to the second position, the feed amount of the printing medium until the sensor detects the leading edge at the first position, and the sensor is the second position An inclination detection method, wherein the inclination is obtained based on a feed amount of the printing medium until the leading edge is detected at a position. The tilt detection method according to any one of claims 1 to 3 ,
The sensor includes a light emitting unit and a light receiving unit, and detects the presence or absence of the printing medium based on an output value of the light receiving unit. A print head movable in the main scanning direction, a printing medium feeding means for feeding the printing medium, and a sensor capable of moving in the main scanning direction and detecting the presence or absence of the printing medium; A printing method by a printing apparatus that performs printing on the printing medium by discharging ink from the printing head,
Positioning the sensor at a first position in the main scanning direction;
Feeding the print medium by the print medium feeding means;
Detecting the leading end of the substrate by the sensor at the first position;
Moving the sensor to a temporary position different from the first position;
Detecting the presence or absence of the substrate by the sensor at the temporary position;
Moving the sensor to a second position opposite to the temporary position when viewed from the first position when the sensor detects that the printing medium is present at the temporary position;
Feeding the print medium by the print medium feeding means;
Detecting the leading end of the substrate by the sensor at the second position;
Obtaining the inclination of the printing material based on the detection result of the leading edge at the first position and the second position;
Changing a start position and / or an end position at which ink is ejected from the print head moving in the main scanning direction according to the obtained inclination;
A printing method that have a,
When the sensor detects that the printing medium is not present at the temporary position, the printing medium feeding means feeds the printing medium without moving the sensor from the temporary position to the second position. Based on the detection result of the leading edge at the first position and the predetermined position, the leading edge of the printing medium is detected by the sensor at a predetermined position on the same side as the temporary position when viewed from the first position. To determine the inclination of the substrate.
A printing method characterized by the above .

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