JP4701785B2 - Image recording device - Google Patents

Description

  The present invention relates to an image recording apparatus in which a sensor of end detection means for detecting a front end and a rear end of a recording medium is mounted on a scanning carriage together with a recording head.

  Conventionally, for example, an ink jet printer is known as an image recording apparatus called a serial printer. In the ink jet printer, ink is guided to the actuator, and the ink is pressurized and ejected using the bending of the actuator such as a piezoelectric element or the electrostrictive element according to the input signal or the local boiling of the ink by the heating element. The head is mounted on a scanning carriage that reciprocates in a direction perpendicular to the conveyance direction of the recording paper. The scanning carriage is scanned each time the recording paper is conveyed with a predetermined line feed width, and the recording head is By ejecting ink based on the input signal, image recording is performed on the recording paper.

  In such an ink jet printer, the end of the recording paper is detected in order to accurately align the position of the image with respect to the recording paper. In particular, when image recording is performed up to the edges of both ends of the recording paper, that is, when borderless printing is performed, it is necessary to accurately detect the positions of both ends of the recording paper.

  The detection of the edge of the recording paper is carried, for example, by mounting an optical sensor having a light emitting unit for irradiating the recording medium with light and a light receiving unit for receiving reflected light from the recording medium on the scanning carriage, Scanning is performed while irradiating the recording paper with light, and the presence or absence of the recording paper is detected based on the magnitude of the reflected light (see, for example, Patent Document 1).

JP 2004-182361 A

  In an image recording apparatus such as an ink jet printer, high-precision and high-speed printing is desired. One of means for realizing high-speed printing is continuous feeding of recording paper. In general paper feeding, the recording paper fed from the paper feed tray is transported through the transport path to the scanning carriage, and image recording is performed by the recording head mounted on the scanning carriage, and the paper is ejected to the paper ejection tray. After that, the next recording sheet is fed from the sheet feeding tray.

  On the other hand, in continuous paper feeding, the next recording paper is fed from the paper feeding tray to the conveyance path before the previous recording paper is discharged to the paper discharge tray. Accordingly, the previous recording sheet and the next recording sheet are simultaneously conveyed on the conveying path in a state where they are separated from each other by a predetermined distance in the conveying direction. As a result, when recording an image on a plurality of recording sheets, there is an advantage that the time required for transporting each recording sheet is reduced and the speed of image recording is increased.

  However, since the optical sensor for detecting both ends of the recording paper and the recording head described above have different positions on the scanning carriage, the recording paper detected by both ends of the optical sensor and the recording head perform image recording. There are cases where the recording paper being used is different, and there are cases where it is not appropriate to immediately apply the both end positions detected by the optical sensor to the recording paper on which image recording is currently being performed. That is, since both end positions of the recording sheet conveyed below the recording head are slightly different for each recording sheet, both end positions of the recording sheet on which image recording is performed next are applied to the recording sheet on which image recording is currently performed. In this case, there is a problem that the position of the recorded image with respect to the recording sheet is shifted.

  The present invention has been made in view of such a problem, and an object of the present invention is to provide means capable of accurately reflecting the detected both-end positions on a recording medium on which image recording is performed.

An image recording apparatus according to the present invention includes a conveying unit that conveys a recording medium on which recording is next performed in a conveying direction before the image recording of the recording medium that is currently recording an image , and an image on the recording medium. A recording head that performs recording, and a sensor that can detect the presence or absence of the recording medium upstream of the recording head in the transport direction of the recording medium and at one end in the scanning direction of the scanning carriage, in addition to the recording head. And a scanning carriage that reciprocates in a scanning direction orthogonal to the conveying direction of the recording medium by the conveying means, and in borderless printing, the scanning carriage is moved and the recording medium is moved based on a detection signal from the sensor. left and right end detecting means for detecting right and left ends in the scanning direction, the borderless printing, contact to the scanning by the scanning carriage is scanned in the scanning direction the recording head That after the image recording has been performed, the recording head is on standby to the scanning carriage to the standby position and the sensor is positioned outside the left and right ends of the recording medium is inside the left and right ends of the recording medium, the transport front and rear end detecting means means detects a pre-rear in the conveying direction of the recording medium on the basis of a detection signal output from the sensor when conveying the recording medium at a predetermined linefeed width, the borderless printing, the left and right Storage means for storing left and right edge information indicating the left and right edge positions of the recording medium detected by the edge detection means in association with a recording medium that is currently recording an image and a recording medium that is next to record an image; in borderless printing, after detecting the trailing edge of the recording medium in which the front and rear end detecting means is performing the current image recording, based on the detection of the front end of the recording medium next record images, Resting a within the image recording, by moving the scanning carriage to detect the right and left ends in the scanning direction of the recording medium based on the detection signal from the sensor, the recording medium associated with the left and right end information next Recording medium determining means for determining that image recording should be performed, and image recording operation of the recording head to each recording medium based on left and right end information stored in the storage means in borderless printing And a control means.

  The conveying means conveys the recording medium on which image recording is performed next to the detection position of the sensor before the image recording of the recording medium on which image recording is currently being performed. With such continuous feeding, it is possible to reduce the time required to record an image on a plurality of recording media.

  The recording medium is conveyed in the conveying direction with a predetermined line feed width by the conveying means, and the scanning carriage is scanned in the scanning direction orthogonal to the conveying direction for each line feed of the recording medium. Image recording is performed. Further, the left and right edge detection means detects the left and right edges of the recording medium based on a detection signal from the sensor by moving the scanning carriage.

The front and rear end detection means waits at the standby position after the scanning carriage is scanned in the scanning direction and image recording is performed by the recording head, and the conveying means is subjected to recording. The front and rear ends of the recording medium are detected based on a detection signal from the sensor when the medium is conveyed with a predetermined line feed width. By waiting the recording head outside the left and right ends of the recording medium, the front end of the recording medium on which image recording is performed next does not come into contact with the recording head. On the other hand, by causing the sensor to stand by on the inner side from the left and right ends of the recording medium, the rear end of the recording medium on which image recording is currently performed can be accurately detected when transporting with a predetermined line feed width. Further, after detecting the rear end of the recording medium on which image recording is currently performed, the front end of the recording medium on which image recording is performed next can be detected with high accuracy.

Based on the detection of the front and rear ends, the recording medium determination means determines that the sensor is positioned on the recording medium on which image recording is to be performed next , pauses the current image recording, moves the scanning carriage, Based on the detection signal, the left and right edges of the recording medium in the scanning direction are detected, and the recording medium associated with the left and right edge information is determined. As a result, the left and right end information stored in the storage means is accurately associated with the recording medium on which image recording is currently performed and the recording medium on which image recording is to be performed next.

  The control means records the image data of the recording medium currently recorded by the recording head based on the left and right edge information related to the current number of recording pages, and then records the recording medium on which the image recording is performed. The image data is recorded based on left and right end information related to the recording medium.

  According to the present invention, in the image recording apparatus, the front and rear end detection means determines a standby position of the scanning carriage based on the left and right end information. Accordingly, at the standby position, the recording head can be reliably positioned outside the recording medium and the sensor can be reliably positioned within the recording medium. The detection of the positions of both ends of the recording medium in the scanning direction by the left and right edge detection means may be performed only in the vicinity of the front end of the recording medium or may be performed for each predetermined transport amount.

  In the image recording apparatus according to the aspect of the invention, the transport unit may transport the recording medium so that one of left and right ends of the recording medium passes on a reference line along the transport direction. The front and rear end detection means sets one end side on the reference line side of the recording medium as the standby position. As a result, regardless of the size of the recording medium on which image recording is performed next, the front and rear ends of the recording medium can be reliably detected with the standby position kept constant.

  In the image recording apparatus, the image recording apparatus further includes recording medium detection means for detecting passage of the recording medium upstream of the scanning carriage in the conveyance direction, and the front and rear end detection means is configured to detect the recording medium. The means detects the front and rear ends of the recording medium by waiting the scanning carriage at the standby position after detecting that the recording medium that is currently recording an image has passed.

  Until the vicinity of the rear end of the recording medium that is currently recording an image reaches the detection position of the sensor, a normal image recording operation is performed without waiting the scanning carriage at the standby position. When the vicinity of the end approaches, the scanning carriage waits at the standby position, and the sensor detects the vicinity of the rear end of the recording medium and the vicinity of the front end of the recording medium on which image recording is performed next. Thereby, detection by the sensor at a position where the front end and the rear end of the recording medium do not exist can be omitted, and the operation speed of image recording is improved.

  Further, the present invention provides the image recording apparatus, wherein the recording head performs image recording of a recording medium on which image recording is currently performed up to a rear end position of the recording medium detected by the front and rear end detecting means. The image recording of the recording medium on which the image recording is performed next is performed within the range after the front end position of the recording medium detected by the front and rear end detecting means. As described above, the front end and the rear end of the recording medium can be accurately detected by the front and rear end detection means because the rear end of the recording medium on which image recording is currently performed and the front end of the recording medium on which image recording is performed next can be accurately detected. Borderless printing can be performed with high precision at the edges.

  Preferably, the sensor includes a light emitting unit that irradiates light to the recording medium and a light receiving unit that receives reflected light from the recording medium. The edge detecting means detects the edge of the recording medium based on whether or not the amount of light received by the light receiving section exceeds a threshold value.

  According to the image recording apparatus of the present invention, the front end of the recording medium on which image recording is performed next can be prevented from contacting the recording head by waiting the recording head outside the left and right ends of the recording medium. Therefore, the recording medium can be prevented from being soiled. In addition, by making the sensor stand inward from the left and right ends of the recording medium, it is possible to detect the front and rear ends of the recording medium when transporting with a predetermined line feed width, so the left and right end information stored in the storage means is detected. Accurately associated with the recording medium. Since the image recording is performed by the recording head based on the left and right end information associated with the recording medium on which image recording is to be performed, for example, when performing borderless printing on the recording medium by the image recording apparatus, each recording medium is recorded. Image recording can be performed with high accuracy on the left and right edges of the recording medium.

  Further, in continuous feeding, when an image is recorded on the recording medium, the recording medium on which image recording is performed next can be transported to the detection position of the sensor, and the feeding time of the recording medium can be reduced. The image recording speed can be improved by shortening. In addition, since the leading and trailing edges of the recording medium can be accurately detected in continuous feeding, borderless printing can be performed with high precision on the front and rear edges of the recording medium.

Embodiments of the present invention will be described below with reference to the drawings as appropriate.
FIG. 1 shows an external configuration of a multifunction machine 1 (image recording apparatus) according to an embodiment of the present invention. The multifunction device 1 is a multi-function device (MFD) having a printer unit 2 at the bottom and a scanner unit 3 at the top, and has a printer function, a scanner function, a copy function, and a facsimile function. . The printer unit 2 of the multifunction machine 1 corresponds to the image recording apparatus according to the present invention, and functions other than the printer function are arbitrary. Accordingly, a single-function printer without the scanner unit 3 and having no scanner function or copy function may be used.

  Further, when the image recording apparatus according to the present invention is implemented as a multi-function apparatus, a plurality of paper feed cassettes and automatic document feeders can be used even if the image recording apparatus is a small one such as the multifunction machine 1 shown in the present embodiment. It may be a large one equipped with (ADF: Auto Document Feeder). The multifunction device 1 is mainly connected to a computer (not shown) and records images and documents on recording paper based on image data and document data transmitted from the computer. Image data output from a digital camera connected to an external device such as a camera is recorded on a recording sheet, or various recording media such as a memory card are loaded, and the image data recorded on the recording medium is recorded on the recording sheet. It is also possible to record in In addition, the configuration of the multifunction machine 1 described below is an example of an image recording apparatus according to the present invention, and it is natural that the configuration can be appropriately changed without departing from the gist of the present invention.

  As shown in FIG. 1, the multifunction device 1 has a wide, thin, rectangular parallelepiped outer shape whose width and depth are larger than the height, and a lower portion of the multifunction device 1 is a printer unit 2. The printer unit 2 has an opening 2a formed in the front, and a paper feed tray 20 and a paper discharge tray 21 are provided in two upper and lower stages so that a part of the opening 2a is exposed. The paper feed tray 20 is for storing recording paper, which is a recording medium, and can accommodate recording papers of various sizes such as B5 size and postcard size, which are A4 size or smaller. Further, as shown in FIG. 2, the sheet feeding tray 20 can expand the tray surface by pulling out the slide tray 20a as necessary. The recording paper stored in the paper feed tray 20 is fed into the printer unit 2 to record a desired image and discharged to the paper discharge tray 21.

  The upper part of the multifunction device 1 is a scanner unit 3, which is configured as a so-called flat bed scanner. As shown in FIGS. 1 and 2, a platen glass 31 and an image sensor 32 are provided below a document cover 30 that can be opened and closed as a top plate of the multifunction machine 1. The platen glass 31 is used to place a document for image reading. Below the platen glass 31, an image sensor 32 whose main scanning direction is the depth direction of the multifunction device 1 is provided so as to be able to scan in the width direction of the multifunction device 1.

  An operation panel 4 for operating the printer unit 2 and the scanner unit 3 is provided in the upper front portion of the multifunction machine 1. The operation panel 4 includes various operation buttons and a liquid crystal display unit. The multifunction device 1 operates based on an operation instruction from the operation panel 4, and also operates based on an instruction transmitted from the computer via a printer driver when connected to the computer. In addition, a slot portion 5 in which various small memory cards as recording media can be loaded is provided in the upper left portion of the front surface of the multifunction device 1. The image data recorded on the small memory card loaded in the slot unit 5 is read out, information on the image data is displayed on the liquid crystal display unit, and an input for recording an arbitrary image on the recording sheet by the printer unit 2 is performed. It can be performed from the operation panel 4.

  Hereinafter, the internal configuration of the multifunction device 1, particularly the configuration of the printer unit 2, will be described with reference to FIGS. 2 to 9. As shown in FIG. 2, on the back side of the paper feed tray 20 provided on the bottom side of the multifunction machine 1, a separation inclined plate for separating and guiding the recording paper loaded on the paper feed tray 20 upward 22 is disposed. Further, the conveyance path 23 is directed upward from the separation inclined plate 22, then bends to the front side, extends from the back side to the front side of the multifunction machine 1, passes through the image recording unit 24, and passes through the paper discharge tray 21. Leads to Accordingly, the recording paper stored in the paper feed tray 20 is guided by the conveyance path 23 so as to make a U-turn from the bottom to the top, reaches the image recording unit 24, and after the image recording is performed by the image recording unit 24. The paper is discharged to the paper discharge tray 21.

  As shown in FIG. 3, on the upper side of the paper feed tray 20, a paper feed roller 25 is provided for separating the recording papers stacked on the paper feed tray 20 one by one and feeding them to the transport path 23. . The paper feed roller 25 is pivotally supported at the front end of a paper feed arm 26 that moves up and down detachably with respect to the paper feed tray 20, and a LF motor 71 ( The drive shown in FIG. 9 is transmitted to rotate.

  The paper feed arm 26 is disposed so as to be swingable in the vertical direction with the base end side as an axis. In the standby state, the paper feed arm 26 is flipped upward as shown in the figure by a paper feed clutch, a spring, etc. (not shown), and swings downward when supplying recording paper. As the paper feed arm 26 swings downward, the paper feed roller 25 pivotally supported at the front end of the paper feed arm 26 presses against the surface of the recording paper on the paper feed tray 20. In this state, when the paper feed roller 25 rotates, the uppermost recording paper is sent out to the separation inclined plate 22 by the frictional force between the roller surface of the paper feeding roller 25 and the recording paper. The front end of the recording sheet comes into contact with the separation inclined plate 22 and is guided upward, and is sent to the conveyance path 23. Further, when the uppermost recording paper is sent out by the paper feed roller 25, the recording paper immediately below it may be sent out together due to friction or static electricity. However, the recording paper abuts against the separation inclined plate 22. Be stopped by.

  The conveyance path 23 includes an outer guide surface and an inner guide surface that are opposed to each other at a predetermined interval except for a portion where the image recording unit 24 and the like are disposed. For example, the conveyance path 23 on the back side of the multifunction device 1 is configured such that the outer guide surface is formed integrally with the frame of the multifunction device 1 and the inner guide surface is fixed to the guide member 28 in the frame. In addition, in the conveyance path 23, particularly in a portion where the conveyance path 23 is bent, the width direction of the conveyance path 23 is set in the axial direction so that each conveyance roller 29 exposes the roller surface to the outer guide surface or the inner guide surface. It is provided as freely rotatable. Each of these transport rollers 29 facilitates transport of the recording paper that contacts the guide surface at a portion where the transport path 23 is bent.

  As shown in FIG. 2, the conveyance path 23 is a conveyance path 23 after a U-turn from below to above, and a registration sensor 33 (recording medium detection means) is provided on the upstream side of the image recording unit 24. Yes. As shown in FIG. 4, the registration sensor 33 includes a detector 34 that rotates so as to retreat from the transport path 23 by contacting a recording sheet that is projected and transported to the transport path 23. The photo interrupter 35 which detects rotation is provided.

  The detector 34 is integrally formed with a shielding portion 36 that is detected by a photo interrupter 35 and is rotatably provided about a shaft 37. The detector 34 is elastically biased by a biasing means such as a spring (not shown) to a position where the detector 34 protrudes into the conveyance path 23, that is, clockwise in the drawing. Therefore, in the state where no external force is applied to the detector 34, the detector 34 protrudes into the transport path 23, and the shielding portion 36 is located between the light emitting portion and the light receiving portion of the photo interrupter 35, as shown in the figure. Thereby, the light transmission of the photo interrupter 35 is interrupted, and the registration sensor 33 is turned off. On the other hand, when the recording paper is transported to the transport path 23, the recording paper abuts on the detector 34, and the recording paper is further transported to rotate the detector 34 so as to retract from the transport path 23. . The shielding unit 36 is also rotated together with the detector 34, and the shielding unit 36 is separated from between the light emitting unit and the light receiving unit of the photo interrupter 35. Thereby, the light transmission of the photo interrupter 35 is not interrupted, and the registration sensor 33 is turned on. By passing the registration sensor 33 on / off, the passage of the recording sheet is detected on the upstream side of the image recording unit 24.

  As shown in FIG. 3, an image recording unit 24 is provided on the downstream side of the registration sensor 33. The image recording unit 24 includes a scanning carriage 38 that is mounted with a recording head 39 and reciprocates in the main scanning direction. The recording head 39 includes cyan (C), magenta (M), yellow (Y), and black through an ink supply pipe 41 from an ink tank 40 (see FIG. 5) installed separately from the recording head 39 in the multifunction device 1. Each color ink of (Bk) is supplied, and each ink is ejected as a minute ink droplet. By scanning the scanning carriage 38 on which the recording head 39 is mounted, image recording is performed on a recording sheet conveyed on the platen 42.

  Specifically, as shown in FIG. 5, a pair of guide rails 43 a and 43 b are extended in the width direction of the conveyance path 23 at a predetermined interval in the conveyance direction of the recording paper on the upper side of the conveyance path 23. The scanning carriage 38 is slidably provided so as to straddle the guide rails 43a and 43b. The guide rail 43a disposed on the upstream side in the conveyance direction of the recording paper is a flat plate whose length in the width direction of the conveyance path 23 is longer than the scanning width of the scanning carriage 38, and the upper surface of the guide rail 43a is The upstream end of the scanning carriage 38 is slidably supported.

  The guide rail 43b disposed on the downstream side in the recording sheet conveyance direction is a flat plate having a length in the width direction of the conveyance path 23 that is substantially the same as the guide rail 43a. An edge 43c that supports the downstream end is bent at a substantially right angle upward. The scanning carriage 38 is slidably supported on the upper surface of the guide rail 43b, and the edge 43c is held by a roller (not shown). Accordingly, the scanning carriage 38 is slidably supported on the guide rails 43a and 43b and reciprocates in the width direction of the transport path 23 with the edge 43c of the guide rail 43b as a reference. A sliding member for reducing friction is appropriately provided at a portion where the scanning carriage 38 contacts the upper surfaces of the guide rails 43a and 43c.

  Further, as shown in the figure, a belt driving mechanism 44 is disposed on the upper surface of the guide rail 43b. The belt drive mechanism 44 is formed by stretching an endless annular timing belt 47 having teeth on the inner side between a drive pulley 45 and a driven pulley 46 provided near both ends in the width direction of the transport path 23. Is. A driving force is input from the CR motor 73 (see FIG. 9) to the shaft of the driving pulley 45, and the timing belt 47 moves circumferentially by the rotation of the driving pulley 45. In addition to the endless annular belt, the timing belt 47 may be one in which both end portions of the endless belt are fixed to the scanning carriage 38.

  The scanning carriage 38 is fixed to the timing belt 47, and the scanning carriage 38 reciprocates on the guide rails 43a and 43b with the edge 43c as a reference by the circumferential movement of the timing belt 47. A recording head 39 is mounted on such a scanning carriage 38, and the recording head 39 can reciprocate with the width direction of the transport path 23 as the main scanning direction. A strip-shaped linear encoder 77 is disposed along the edge 43c. The linear encoder 77 is detected by a photo interrupter, and the reciprocating movement of the scanning carriage 38 is controlled.

  As shown in FIG. 3, a platen 42 is disposed below the conveyance path 23 so as to face the recording head 39. The platen 42 is disposed over the central portion of the reciprocating range of the scanning carriage 38 through which the recording paper passes. The width of the platen 42 is sufficiently larger than the maximum width of the recording paper that can be conveyed, and both ends of the recording paper always pass over the platen 42. The color of the upper surface of the platen 42 carrying the recording paper is preferably a color having a reflectance different from that of white which is a general recording paper color, and particularly preferably black.

  Further, as shown in FIG. 5, a maintenance unit such as a purge mechanism 48 and a waste ink tray (not shown) is disposed outside the range in which the recording paper does not pass, that is, outside the image recording range by the recording head 39. The purge mechanism 48 is for sucking and removing bubbles and foreign matters together with ink from the nozzles 53 of the recording head 39 and the like. The purge mechanism 48 includes a cap 49 that covers the nozzle surface of the recording head 39, a pump mechanism (not shown) that is connected to the recording head 39 through the cap 49, and the cap 49 that is in contact with and away from the nozzle surface of the recording head 39. And a moving mechanism (not shown). When performing suction removal of bubbles or the like of the recording head 39, the scanning carriage 38 is moved so that the recording head 39 is positioned on the cap 49, and the cap 49 moves upward in this state, and the lower surface of the recording head 39. The ink discharge port 53a (see FIG. 6) is tightly sealed so that ink is sucked from the nozzle 53 of the recording head 39 by a pump connected to the cap 49.

  On the other hand, although not shown in the drawing, a waste ink tray for receiving idle ink discharge from the recording head 39 called flushing is also provided within the reciprocating movement range of the scanning carriage 38 and outside the image recording range. By these maintenance units, maintenance such as removal of air bubbles and mixed color ink in the recording head 39 is performed. It should be noted that maintenance units such as the purge mechanism 48 and the waste ink tray are optional in the present invention.

  As shown in FIG. 1, the ink tank 40 is accommodated in an ink tank accommodating portion 6 provided in a housing on the front side of the printer unit 2 and on the left side (right side in the drawing). As shown in FIG. 5, the ink tank 40 is provided in the apparatus separately from the scanning carriage 38 on which the recording head 39 is mounted, and ink is supplied to the scanning carriage 38 through the ink supply pipe 41. It has become so.

  The ink tank 40 includes four ink tanks 40C, 40M, 40Y, and 40K that store cyan (C), magenta (M), yellow (Y), and black (Bk) color inks. The ink storage unit 6 is loaded at predetermined positions. Although not shown in detail in the drawing, each of the ink tanks 40C, 40M, 40Y, and 40K is a cartridge type in which each color ink is filled in a synthetic resin casing, and is attached and detached from above the ink containing portion 6. It is possible. At the bottom of the casing of each ink tank 40C, 40M, 40Y, 40K, an opening for supplying each color ink stored therein is formed, and the opening is sealed by a check valve. The ink container 6 is provided with a joint for opening the check valve. When the ink tanks 40C, 40M, 40Y, and 40K are loaded in the ink container 6, the check valve for the opening is opened. Is opened, and ink can be supplied from the opening.

  In the present embodiment, the multifunction device 1 that performs image recording with four colors of ink is described. However, the number of ink colors in the image recording apparatus according to the present invention is not particularly limited. Of course, when performing image recording with eight-color ink, it is possible to increase the ink tank. Further, the ink tank 40 is not limited to the cartridge type, and may be installed in the apparatus casing and replenished with ink as appropriate.

  Each color ink is supplied from the ink tanks 40C, 40M, 40Y, and 40K loaded in the ink storage unit 6 to the recording head 39 by the ink supply pipe 41 independent for each color. Each of the ink supply tubes 41C, 41M, 41Y, and 41K is a tube made of synthetic resin, and has such flexibility that it bends according to the scanning of the scanning carriage 38. Although not shown in detail in the drawing, each of the ink supply pipes 41C, 41M, 41Y, and 41K has an opening on one end side thereof at each joint portion provided at each ink tank housing position of the ink housing portion 6. Each is connected. The ink supply pipe 41C corresponds to the ink tank 40C and supplies cyan (C) ink. Similarly, the ink supply pipes 41M, 41Y, and 41K correspond to the ink tanks 40M, 40Y, and 40K, respectively, and supply magenta (M), yellow (Y), and black (Bk) inks, respectively. Is.

  Each of the ink supply pipes 41C, 41M, 41Y, 41K led out from the ink containing portion 6 is pulled out to the vicinity of the center along the width direction of the apparatus, and is temporarily fixed to an appropriate member such as an apparatus frame. The portion from the fixed portion to the scanning carriage 38 is not fixed to the apparatus frame or the like, and changes its posture following the reciprocating movement of the scanning carriage 38. That is, as the scanning carriage 38 moves to one end (left side in the figure) in the reciprocating direction, each ink supply tube 41C, 41M, 41Y, 41K is bent so that the bending radius of the U-shaped curved portion becomes smaller. The scanning carriage 38 moves in the moving direction. On the other hand, as the scanning carriage 38 moves to the other end (the right side in the figure) in the reciprocating direction, each ink supply tube 41C, 41M, 41Y, 41K bends so that the bending radius of the curved portion increases, while the scanning carriage 38 Move in the direction of movement.

  As shown in FIG. 6, a media sensor 50 is mounted on the scanning carriage 38 together with the recording head 39. As shown in FIGS. 6 and 7, the media sensor 50 includes a light emitting unit 51 made of a light emitting diode and a light receiving unit 52 made of an optical sensor. As shown in FIG. 7, the light emitting unit 51 of the media sensor 50 emits light toward the platen 42, and the light receiving unit 52 receives the reflected light of the light. As described above, the color of the upper surface of the platen 42 is a color having a reflectance different from that of the recording paper P, such as black, and when the recording paper P is not present, the reflected light from the platen 42 having a low reflectance. Therefore, the detection value (AD value) of the media sensor 50 is a low value. On the other hand, when the recording sheet P exists, the light receiving unit 52 receives the reflected light from the recording sheet P having a high reflectance, so that the detection value (AD value) of the media sensor 50 is a high value. As shown in FIG. 6, such a media sensor 50 is mounted on the scanning carriage 38 on the upstream side in the transport direction of the recording head 39 and at one end in the scanning direction, and reciprocates in the scanning direction by the scanning carriage 38. It is like that.

  As shown in FIG. 6, the recording head 39 has ink discharge ports 53a arranged on the lower surface thereof in the recording paper transport direction for each color ink of CMYBk. Note that the pitch and number of the ink ejection ports 53a in the transport direction are appropriately set in consideration of the resolution of the recorded image. It is also possible to increase or decrease the number of columns of the ink discharge ports 53a according to the number of types of color ink.

  As shown in FIG. 8, the lower ends of the nozzles 53 arranged in the lower part of the recording head 39 are opened in the lower surface of the recording head 39 to form the ink discharge ports 53a. On the upper end side of the nozzle 53, a manifold 54 is formed across a plurality of nozzles 53 for each color ink. The manifold 54 includes a supply pipe 55 formed on one end side of the nozzles 53 arranged in a row and a manifold chamber 56 formed over the upper ends of the nozzles 53, and is supplied from the supply pipe 55. The ink is distributed to each nozzle 53 through the manifold chamber 56.

  The surface of the manifold chamber 56 facing the nozzles 53 is inclined so as to descend toward the downstream side where the ink flows, and the sectional area of the manifold chamber 56 is configured to decrease toward the downstream side. Yes. The mechanism in which each nozzle 53 ejects the ink distributed by the manifold 54 as an ink droplet from the ink ejection port 53a is, for example, a structure in which the side wall of the nozzle 53 is made of a piezoelectric material and the ink droplet is ejected by deformation of the piezoelectric material. Alternatively, other known mechanisms can be employed.

  Further, a buffer tank 57 is disposed above the manifold 54. The buffer tank 57 is provided for each color ink of CMYBk similarly to the nozzle 53 and the manifold 54. Each buffer tank 57 is supplied with ink from an ink supply port 58 through an ink supply pipe 41 from the ink tank 40 as shown in FIG. In this way, by temporarily storing the ink in the buffer tank 57 without supplying ink directly from the ink tank 40 to the nozzle 53, bubbles generated in the ink can be captured by the ink supply pipe 41 or the like. Air bubbles can be prevented from entering the wall. Air bubbles trapped in the buffer tank 57 are sucked and removed from the air bubble outlet 59 by a pump mechanism (not shown).

  The buffer tank 57 is connected to the manifold chamber 56 through the supply pipe 55. As a result, the flow path is configured such that each color ink supplied from the ink tank 40 flows to the nozzle 53 via the buffer tank 57 and the manifold 54. CMYBk color inks supplied through such a flow path are ejected as ink droplets from the ink ejection port 53a onto the recording paper.

  As shown in FIG. 3, on the upstream side of the image recording unit 24, there are a pair of transport rollers 60 and a pressing roller 61 that sandwich the recording paper transported through the transport path 23 and transport it onto the platen 42. Is provided. On the other hand, on the downstream side of the image recording unit 24, a pair of paper discharge rollers 62 and a spur roller 63 are provided for nipping and transporting recorded recording paper. The conveying roller 60 and the paper discharge roller 62 are intermittently driven with a predetermined line feed width when the driving force is transmitted from the LF motor 71. The rotation of the transport roller 60 and the paper discharge roller 62 is synchronized, and the rotation of the transport roller 60 and the paper discharge roller 62 is detected by detecting a rotary encoder 76 (see FIG. 9) provided on the transport roller 60 with a photo interrupter. Is controlled.

  On the other hand, the pressing roller 61 is urged so as to be pressed against the conveying roller 60 with a predetermined pressing force and is rotatably provided. When a recording sheet enters between the conveying roller 60 and the pressing roller 61, the pressing roller 61 retreats by the thickness of the recording sheet and holds the recording sheet together with the conveying roller 60. Thereby, the rotational force of the conveyance roller 60 is reliably transmitted to the recording paper. The spur roller 63 is also provided in the same manner as the paper discharge roller 62. However, since the spur roller 63 is in pressure contact with the recorded recording paper, the roller surface is uneven in a spur shape so as not to deteriorate the image recorded on the recording paper. It has become.

  The recording paper held between the transport roller 60 and the pressing roller 61 is intermittently transported on the platen 42 with a predetermined line feed width. The recording head 39 is scanned for each line feed, and image recording is performed from the front end side of the recording paper. Thereafter, the front end side of the recording paper on which image recording has been performed is held between the paper discharge roller 62 and the spur roller 63. Accordingly, the recording sheet is intermittently conveyed with a predetermined line feed width with the front end side being sandwiched between the paper discharge roller 62 and the spur roller 63 and the rear end side being sandwiched between the transport roller 60 and the pressing roller 61. Similarly, image recording is performed by the recording head 39. When the recording sheet is further conveyed, the trailing end of the recording sheet passes through the conveying roller 60 and the pressing roller 61, and the nipping by these is released. Accordingly, the recording sheet is sandwiched between the paper discharge roller 62 and the spur roller 63 and intermittently conveyed with a predetermined line feed width, and image recording is performed by the recording head 39 in the same manner. After image recording is performed on a predetermined area of the recording paper, the paper discharge roller 62 is continuously rotated. As a result, the recording paper held by the paper discharge roller 62 and the spur roller 63 is discharged to the paper discharge tray 21. The conveying roller 60, the pressing roller 61, the paper discharge roller 62, the spur roller 63, and the paper feeding roller 25 as described above constitute a conveying means according to the present invention.

  FIG. 9 shows the configuration of the control unit 64 (recording medium determination unit and control unit) of the multifunction machine 1. The control unit 64 controls the overall operation of the multi-function device 1 including not only the scanner unit 2 but also the printer unit 3, but a detailed description of the configuration of the scanner unit 3 is omitted in the present embodiment. As shown in the figure, the control unit 64 is configured as a microcomputer mainly including a CPU 65, a ROM 66, a RAM 67 (storage means), and an EEPROM 68, and is connected to an ASIC (Application Specific Integrated Circuit) 70 via a bus 69. ing.

  The ROM 66 stores programs for controlling various operations of the multifunction machine 1. The RAM 67 is used as a storage area or a work area for temporarily recording various data used when the CPU 65 executes the program.

  The ASIC 70 generates a phase excitation signal and the like for energizing the LF (conveyance) motor 71 in accordance with a command from the CPU 65, applies the signal to the drive circuit 72 of the LF motor 71, and drives the drive signal via the drive circuit 72. The LF motor 71 is rotated by energizing the LF motor 71.

  The drive circuit 72 drives the LF motor 71 connected to the paper feed roller 25, the transport roller 60, the paper discharge roller 62, and the purge mechanism 48, receives an output signal from the ASIC 70, and receives the LF motor 71. An electric signal for rotating the is formed. In response to the electrical signal, the LF motor 71 rotates, and the rotational force of the LF motor 71 is fed via a known drive mechanism including a gear, a drive shaft, and the like, through the paper feed roller 25, the transport roller 60, the paper discharge roller 62, And is transmitted to the purge mechanism 48.

  Similarly, the ASIC 70 generates a phase excitation signal and the like for energizing a CR (carriage) motor 73 in accordance with a command from the CPU 65, applies the signal to the drive circuit 74 of the CR motor 73, and passes through the drive circuit 74. Thus, the rotation control of the CR motor 73 is performed by energizing the CR motor 73 with a drive signal.

  The drive circuit 74 drives the CR motor 73 connected to the scanning carriage 38 and receives an output signal from the ASIC 70 to form an electrical signal for rotating the CR motor 73. Upon receipt of the electrical signal, the CR motor 73 rotates, and the rotational force of the CR motor 73 is transmitted to the scanning carriage 38 via the belt drive mechanism 44, whereby the scanning carriage 38 is scanned.

  The drive circuit 75 selectively ejects ink from the recording head 39 to the recording paper at a predetermined timing. The drive circuit 75 receives an output signal generated by the ASIC 70 based on a drive control procedure output from the CPU 65. The recording head 39 is driven and controlled.

  The ASIC 70 also includes a registration sensor 33 for detecting a recording sheet in the conveyance path 26, a rotary encoder 76 for detecting the rotation amount of the conveyance roller 60, and a linear encoder for detecting the movement amount of the scanning carriage 38. 77, a media sensor 50 for detecting the presence or absence of recording paper is connected. The detection signal of the media sensor 50 is stored in the RAM 67 via the ASIC 70 and the bus 69, and the CPU 65 analyzes the detection signal based on the program stored in the ROM 66 to determine the end of the recording paper. Thereby, the left and right end detection means and the front and rear end detection means of the present invention are realized.

  Further, the ASIC 70 includes a scanner unit 3, an operation panel 4 for instructing operation of the multifunction device 1, a slot unit 5 into which various small memory cards are inserted, an external device such as a personal computer, and a parallel cable or a USB cable. A parallel interface 78 and a USB interface 79 for transmitting and receiving data are connected. Further, an NCU (Network Control Unit) 80 and MODEM 81 for realizing a facsimile function are also connected.

  As shown in FIG. 5, the control unit 64 includes a main board 82, and recording signals and the like are transmitted from the main board 82 to the recording head 39 through the flat cable 83. The flat cable 83 is a ribbon-like one in which a conductor for transmitting an electrical signal is covered with a synthetic resin film such as a polyester film and insulated, and the main board 82 and the control board (not shown) of the recording head 39 are electrically connected. Connected. Further, the flat cable 83 is led out from the scanning carriage 38 in the reciprocating direction, and is bent in a substantially U shape in the vertical direction. The substantially U-shaped portion is not fixed to other members, and is scanned. The posture changes following the reciprocation of the carriage 38.

Hereinafter, an image recording operation in the printer unit 2 will be described.
As shown in the flowchart of FIG. 10, when print data is transmitted from a computer or a small memory card to the control unit 64 (S10), the printer unit 2 of the multi-function device 1 causes the recording paper P held in the paper feed tray 20 to be printed. Is started (S20). That is, the LF motor 71 is driven and transmitted to the paper feed roller 25, the transport roller 60 and the paper discharge roller 62, and the recording paper P is fed from the paper feed tray 20 to the transport path 23. The recording sheet P is conveyed while being reversed so as to make a U-turn upward along the conveying path 23, and the front end of the recording sheet P is detected by the registration sensor 33 as shown in FIG. Then, after the registration sensor 33 detects the recording paper P, the rotation amount input to the conveyance roller 60 and the like is grasped as the encoder amount of the rotary encoder 76, and the vicinity of the front end of the recording paper P is directly below the media sensor 50. Then, the recording paper P is conveyed. Then, the control unit 64 turns off the paper trailing edge detection flag and the paper leading edge detection flag (S21). These sheet trailing edge detection flag and sheet leading edge detection flag are stored in the EEPROM 68.

  Subsequently, the paper width is detected near the front end of the recording paper P (S30). FIG. 13 is a flowchart of the paper width detection process. First, as shown in FIG. 12, the scanning carriage 38 is moved so that the media sensor 50 is positioned at the center of the sheet (S301). As shown in the figure, the recording paper P is conveyed with the center of the conveying path 23 as a reference line L, and the central positions of the recording papers P of all sizes are on the reference line L. Accordingly, the scanning carriage 38 is moved so that the media sensor 50 is on the reference line L.

  Subsequently, the light amount of the media sensor 50 is adjusted at the center position (S302). As described above, the end detection means in the printer unit 2 is realized by the media sensor 50 and the control unit 64. When the light emitting unit 51 of the media sensor 50 is energized with a predetermined current value, the light emitting unit 51 emits light with a predetermined light emission amount. The light emission amount of the light emitting unit 51 is appropriately adjusted according to the type of recording paper. For example, a glossy paper for photographic printing in which a predetermined process is performed on the surface of the paper has a higher reflectance than that of plain paper, and thus the amount of light received by the light receiving unit 52 is increased. Similarly, the amount of received light changes if the surface color of the recording paper is different. Therefore, the light emission amount of the light emitting unit 51 is adjusted so that the light reception amount of the light receiving unit 52 is constant when there is a recording sheet.

  Such adjustment of the light emission amount is performed as follows. The media sensor 50 is turned on at the center position shown in FIG. The initial light emission amount is a small amount of light so that the light reception amount does not reach the target value with any paper type. Therefore, the light reception amount of the light receiving unit 52 is smaller than the target value at the initial light emission amount. Thereafter, the light emission amount of the light emitting unit 51 is increased for each predetermined unit of light emission amount, and when the light reception amount of the light receiving unit 52 reaches the target value, the light emission amount is determined as an adjustment value.

  Next, in order to detect the left and right edges of the recording paper P, the scanning carriage 38 moves from the center position shown in FIG. 12 to a paper width detection start position outside the range of the recording paper P (S303). The moving side may be either left or right in the scanning direction, but here, the scanning carriage 38 is moved to the left in the figure. Whether it is out of the range of the recording paper P can be determined from, for example, the recording paper size indicated by the recording paper information included in the print data output from the computer, and the scanning carriage 38 is movable. If it is moved to the end, it will be out of the range of the recording paper of the maximum width capable of image recording.

  Then, the media sensor 50 is turned on (S304), and the scanning carriage 38 is moved to the side opposite to the paper width detection start position, that is, the right side in FIG. 12 (S305). Light is emitted from the light emitting unit 51 of the media sensor 50 with the adjusted light emission amount, and the light receiving unit 52 receives the reflected light of the light. The AD value that is the output value of the light receiving unit 52 is stored in the RAM 67 of the control unit 64 in association with the encoder amount of the linear encoder 77 serving as the position information of the scanning carriage 38. Then, the scanning carriage 38 is moved out of the range of the recording paper P opposite to the scanning start position, and the media sensor 50 is turned off (S306). During this time, the AD value output from the light receiving unit 52 is stored in the RAM 67.

  Based on the AD value stored in the RAM 67, the left and right ends of the recording paper P are detected. For example, in the vicinity of the left end of the recording paper P in FIG. 12, the AD value recorded in the RAM 67 is as shown in the graph in FIG. When there is no recording paper P at the corresponding position of the media sensor 50, that is, when the light receiving unit 52 receives reflected light from the platen 42, the AD value output by the light receiving unit 52 is a low first output level. . When the AD value increases near the left end of the recording paper P and falls within the range of the recording paper P, the light receiving unit 52 receives the reflected light from the recording paper P, and the AD value output by the light receiving unit 52 is high. The second output level is set. Then, the position where the detected AD value becomes the paper edge detection threshold set between the first output level and the second output level is determined as the paper edge position. The paper edge detection threshold is set to an intermediate value between the first output level and the second output level, for example. In the vicinity of the right end of the recording paper P, the AD value output by the light receiving unit 52 changes from the second output level to the first output level, and thus the position that becomes the paper end detection threshold during this time is determined as the paper end position. Thus, by detecting the positions of the left and right ends of the recording paper P near the front edge of the recording paper P, the width of the recording paper P can be accurately grasped before image recording.

  The detected left and right edge positions of the recording paper P are stored in the RAM 67 as edge information (S307). At this time, the control unit 64 determines whether the detected left and right end positions of the recording paper P are those of the recording paper P on which image recording is currently performed or the recording paper Pn on which image recording is performed next. Specifically, the determination is made based on ON / OFF of the sheet trailing edge detection flag and the sheet leading edge detection flag stored in the EEPROM 68. That is, if the paper trailing edge detection flag is off and the paper leading edge detection flag is off, the media sensor 50 is on the recording paper P that is currently recording an image, and the control unit 64 detects the left and right edges detected. The position is determined to be that of the recording paper P. If the sheet trailing edge detection flag is on and the sheet leading edge detection flag is off, the media sensor 50 exists between the recording sheet P and the recording sheet Pn, and the control unit 64 detects left and right ends. Not performed. If the sheet trailing edge detection flag is on and the sheet leading edge detection flag is on, the media sensor 50 is on the recording sheet Pn on which image recording is next performed, and the control unit 64 detects the detected left and right edge positions. Is determined to be for the recording paper Pn. Here, since the sheet trailing edge detection flag is off and the sheet leading edge detection flag is off in step S21, the control unit 64 uses the detected left and right edge positions as the recording sheet on which image recording is currently being performed. The data is stored in the RAM 67 as P end information.

  Next, as shown in FIG. 10, the recording paper P is transported by a predetermined transport amount (LF amount) (S40). As shown in FIG. 15, the recording paper P sandwiched between the transport roller 60 and the pressing roller 61 is transported with a predetermined line feed width, and the recording head 39 mounted on the scanning carriage 38 is scanned for each line feed. Then, image recording is performed from the front end side of the recording paper P (S50). Specifically, as shown in FIG. 16, it is determined whether or not x mm or more has been conveyed after the registration sensor 33 detects the absence of the recording paper P (S401). This xmm is used to determine whether or not the vicinity of the rear end of the recording paper P has reached directly below the media sensor 50. For example, the transport distance after the registration sensor 33 detects the absence of the recording paper P. That is, it is set based on the encoder amount of the rotary encoder 76 indicating the rotation amount input to the conveying roller 60 and the like, and the distance of the conveying path from the registration sensor 33 to the media sensor 50. Therefore, in the state shown in FIG. 15, since the registration sensor 33 detects the presence of the recording paper P, the recording paper P is conveyed by a conveyance amount corresponding to a predetermined line feed width (S402).

  After the recording paper P is conveyed with a predetermined line feed width, the scanning carriage 38 is scanned to perform image recording with the recording head 39. Specifically, as shown in FIG. 17, the edge information of the recording paper P stored in the RAM 67 is read (S501), and the print data and the recording paper P are recorded based on the left and right edge positions included in the edge information. Position alignment is performed, and image recording is performed by ejecting ink from the recording head 39 at a predetermined timing (S502).

  In general, when an image is recorded on the recording paper P, print data including recording paper information is transmitted from the computer or the like to the multi function device 1, and the size of the recording paper P is indicated in the recording paper information. . Therefore, the control unit 64 can also control the operations of the scanning carriage 38 and the recording head 39 based on the recording sheet information. However, the recording paper P is not always accurately conveyed to the same position on the platen 42, and the position in the width direction on the platen 42 is slightly different for each conveyance of the recording paper P. In the case of so-called borderless printing in which image recording is performed up to the left and right edges of the recording paper P, portions where no image recording is performed occur on the left and right edges of the recording paper P in order to prevent so-called white residue. In order to minimize the amount of ink ejected by the recording head 39 outside the range of the recording paper P, the position of the left and right ends of the recording paper P is accurately grasped, and the scanning carriage is based on the positions of the left and right ends. By controlling the operations of the recording head 38 and the recording head 39, it is possible to record an image with high accuracy on the left and right edges of the recording paper P.

  Then, after the recording head 39 finishes recording an image for one line feed width, it is determined whether or not print data for the next page is transmitted from a computer or the like (S60). If the image to be recorded is only for one page, paper width detection (S30), line feed (S40), and image recording (S50) are repeated until the print data for one page is completed. When the print data is finished (S70), the image recording is finished without feeding the next page (S80, S90). In this embodiment, the sheet width detection (S30) is performed for each predetermined line feed width. However, the sheet width detection may be performed for each predetermined transport amount wider than the line feed width. However, in order to perform accurate image recording on the left and right edges of the recording paper P in borderless printing, a plurality of times at least every predetermined conveyance with respect to one page of recording paper. It is preferable to perform sheet width detection.

  On the other hand, when there are a plurality of pages of images to be recorded and the next page data is transmitted after the print data for one page is completed, it is determined whether or not it is the paper feed timing of the next page ( S61). In this multifunction machine 1, the recording paper P can be continuously fed. Therefore, before the recording paper P on which image recording is currently being performed is completely discharged to the paper discharge tray 21, the recording paper Pn on which the next image recording is performed is performed. The paper is fed from the paper feed tray 20 to the transport path 23 at a predetermined timing (S62).

  For example, when the registration sensor 33 detects that there is no recording sheet P on which image recording is currently performed, the continuous sheet feeding is performed by immediately feeding the recording sheet Pn on which the next image recording is performed. The recording paper P on which image recording is currently performed is intermittently conveyed while image recording is performed with a predetermined line feed width by the conveyance roller 60 and the paper discharge roller 62, but the recording paper Pn on which image recording is to be performed next. Is continuously conveyed by the paper feed roller 25. Thereby, the recording paper Pn is conveyed faster than the recording paper P. After the registration sensor 33 detects the presence of the recording paper Pn, the recording paper Pn is also conveyed intermittently in synchronization with the recording paper P. Accordingly, the recording paper P on which image recording is currently being performed and the recording paper Pn on which image recording is to be performed next are transported along the transport path 23 with a predetermined distance therebetween in the transport direction. As a result, when image recording is performed on a plurality of recording papers P, the time required for transporting each recording paper P is reduced, and the time required for image recording is reduced.

Hereinafter, detection of the rear end of the recording sheet P on which image recording is currently performed in continuous paper feeding and the front end of the recording sheet P on which image recording is to be performed next will be described.
As shown in FIG. 18, by continuous feeding, the recording paper P on which image recording is currently being performed and the recording paper Pn on which image recording is to be performed next are separated from the recording paper P in the transport direction and are transported synchronously. It is being transported along the path 23. As shown in the figure, since the media sensor 50 and the recording head 39 are at different positions in the transport direction in the scanning carriage 38, the recording head 39 performs image recording on the recording paper P on which image recording is currently being performed. In this case, the media sensor 50 can detect the recording paper Pn on which image recording is performed next. In order to perform borderless printing from the front end of the recording paper Pn with high accuracy, if the media sensor 50 can detect the recording paper Pn, it is necessary to detect the left and right ends of the recording paper Pn.

  Furthermore, in order to accurately align the position of the recording image with respect to the recording paper P, for example, for borderless printing, it is necessary to accurately detect the position of the trailing edge of the recording paper P. Similarly, the recording paper Pn It is necessary to accurately detect the position of the front end. Further, when a paper jam occurs after the registration sensor 33 detects that the recording paper Pn is present, whether the recording paper P is jammed or the image recording on the recording paper P is finished, and the recording paper Pn is jammed. It is also necessary for the control unit 64 to determine whether or not the recording paper should be reprinted after the cancellation. Therefore, when performing borderless printing or continuous paper feeding, it is necessary to accurately detect between the recording paper P and the recording paper Pn, that is, between the papers.

  As shown in FIG. 16, it is determined whether or not x mm or more has been conveyed since the registration sensor 33 detected the absence of the recording paper P (S401). As shown in FIG. 19, when the vicinity of the rear end of the recording paper P has reached just below the media sensor 50, the scanning carriage 38 is set for each line feed width in order to detect the rear end of the recording paper P. After the image is recorded, the recording paper P is conveyed by the line feed width by waiting at the standby position. In the state shown in FIG. 19, since the trailing edge of the recording paper P has not yet been detected, the paper trailing edge detection flag is off (S411). In this manner, until the vicinity of the rear end of the recording sheet P on which image recording is currently performed reaches the detection position of the media sensor 50, normal image recording operation is performed without waiting the scanning carriage 38 at the standby position. When the vicinity of the rear end of the recording paper P reaches the detection position of the media sensor 50, the scanning carriage 38 is put on standby at the standby position so that the rear end of the recording paper P and the front end of the recording paper Pn on which image recording is performed next are performed. By detecting it, it is possible to omit the front end and rear end detection operation at a position other than the front end or the rear end of the recording paper P, and the operation speed of image recording is improved.

  Specifically, as shown in FIG. 19, the recording head 39 is outside the range of the recording paper P, that is, on the right side of the right end of the recording paper P in the drawing, and the media sensor 50 is within the recording paper, that is, the recording in the drawing. The scanning carriage 38 is put on standby at a standby position on the left side of the right end of the paper P. At this standby position, the media sensor 50 is turned on (S412). This standby position is determined based on the edge information of the recording paper P that has already been detected. Therefore, it is possible to reliably position the recording head 39 outside the range of the recording paper P and the media sensor 50 within the range of the recording paper P.

  Then, with the scanning carriage 38 in the standby position, the transport roller 60 and the paper discharge roller 62 are driven to transport the recording paper P and the recording paper Pn with a predetermined line feed width (S413). Since the recording head 39 stands by outside the range of the recording paper P, even if the recording paper P and the recording paper Pn are conveyed in this state, they do not contact the recording head 39. In particular, the recording paper Pn on which image recording is to be performed next is conveyed so as to be reversed from the bottom to the top, and its front end tends to protrude upward, but the front end of the recording paper Pn contacts the recording head 39. There is nothing.

  On the other hand, by making the media sensor 50 stand by within the range of the recording paper P, the rear end of the recording paper P on which image recording is currently performed can be accurately detected when transporting with a predetermined line feed width (S414). ). The method for detecting the trailing edge of the recording paper P is the same as the method for detecting the left and right edges of the recording paper P. That is, the recording paper P is conveyed with the media sensor 50 turned on, and during that time, light is emitted from the light emitting unit 51 of the media sensor 50, and reflected light of the light is received by the light receiving unit 52. The AD value that is the output value of the light receiving unit 52 is stored in the RAM 67 of the control unit 64 in association with the encoder amount of the rotary encoder 76 of the transport roller 60. Based on the AD value stored in the RAM 67, the trailing edge of the recording paper P is detected from the paper edge detection threshold. When the trailing edge of the recording paper P is detected, the paper trailing edge detection flag is turned on and stored in the EEPROM 68 (S415), and the media sensor 50 is turned off (S416).

  The control unit 64 records the edge information until the trailing edge detection flag is stored in the EEPROM 68 as ON, that is, the edge information up to the trailing edge position of the recording sheet P. Is stored in the RAM 67 as the edge information. On the other hand, if the trailing edge of the recording paper P is not detected, the media sensor 50 is turned off while the paper trailing edge detection flag remains off (S416).

  If the trailing edge position of the recording paper P is detected, the control unit 64 uses the edge information of the recording paper P stored in the RAM 67 to determine the print data on which image recording is currently being performed as the detected recording paper. The ink ejection of the recording head 39 is controlled so as to be performed within the range up to the rear end position of P. As a result, borderless printing can be accurately performed on the trailing edge of the recording paper P.

  Even after detecting the trailing edge of the recording paper P, until the leading edge of the recording paper Pn on which image recording is to be performed next is detected, the recording head 39 is outside the range of the recording paper P as shown in FIG. The media sensor 50 causes the scanning carriage 38 to wait at a standby position that is within the range of the recording paper. In this state, since the front end of the recording paper Pn is not detected, the paper front end detection flag is off (S421). At this standby position, the media sensor 50 is turned on (S422).

  Then, with the scanning carriage 38 in the standby position, the transport roller 60 and the paper discharge roller 62 are driven to transport the recording paper P and the recording paper Pn with a predetermined line feed width (S423). As described above, since the recording head 39 is waiting outside the range of the recording paper Pn, even if the recording paper P and the recording paper Pn are conveyed in this state, the front end of the recording paper Pn contacts the recording head 39. Never do.

  On the other hand, since the media sensor 50 stands by at a position within the range of the recording paper Pn, when the recording paper Pn is conveyed with a predetermined line feed width, the front end of the recording paper Pn on which image recording should be performed next is accurately performed. It can be detected (S424). The method for detecting the front edge of the recording paper P is the same as the method for detecting the left and right edges of the recording paper P. That is, the recording paper Pn is conveyed with the media sensor 50 turned on, and light is emitted from the light emitting unit 51 of the media sensor 50 during that time, and the reflected light of the light is received by the light receiving unit 52. The AD value that is the output value of the light receiving unit 52 is stored in the RAM 67 of the control unit 64 in association with the encoder amount of the rotary encoder 76 of the transport roller 60. Based on the AD value stored in the RAM 67, the front end of the recording paper Pn is detected from the paper end detection threshold. When the front edge of the recording paper Pn is detected, the paper front edge detection flag is turned on and stored in the EEPROM 68 (S425).

  The control unit 64 uses the end information from the front end position of the recording paper Pn after the paper front end detection flag is stored as ON in the EEPROM 68, that is, the end of the recording paper Pn on which image recording is performed next. The information is stored in the RAM 67 as information. After the front edge detection flag is stored in the EEPROM 68, a normal image recording operation is performed without causing the scanning carriage 38 to wait at the standby position. That is, after the recording paper P is conveyed with a predetermined line feed width, ink is ejected from the recording head 39 at a predetermined timing based on the edge information of the recording paper P stored in the RAM 67 while scanning the scanning carriage 38. Image recording. Then, the recording paper P is transported with a predetermined line feed width in a state where the scanning carriage 38 is positioned outside the range of the recording paper P without waiting at the standby position, and the scanning carriage 38 is similarly scanned. Image recording is performed by the recording head 39. On the other hand, if the front edge of the recording paper Pn is not detected, the media sensor 50 is turned off with the paper front edge detection flag being off (S426).

  When the front end position of the recording paper Pn is detected and the paper front end detection flag is on and the recording paper Pn is conveyed by a certain amount from the front end position (S431), the control unit 64 turns on the media sensor 50. (S432), sheet width detection is performed near the front end of the recording sheet Pn (S433). The position where the sheet width should be detected is set by the transport amount from the front end position in consideration of the possibility of skew of the recording sheet Pn.

  Further, when the recording paper Pn is not conveyed by a certain amount from the front end position of the recording paper Pn, the recording paper Pn is conveyed by a specified amount (S434). The control unit 64 then discharges ink from the recording head 39 based on the edge information of the recording sheet P recorded in the RAM 67 in order to print the print data on which image recording is currently performed on the recording sheet P (S50). Control.

  FIG. 21 shows a state in which the media sensor 50 is on the recording paper Pn and is at a predetermined position from the front end of the recording paper Pn, that is, a position for detecting the paper width at the front end of the recording paper Pn. In this state, the recording head 39 is in the vicinity of the rear end of the recording paper P and performs image recording on the recording paper P. When the recording paper Pn is conveyed and the media sensor 50 reaches the position shown in the drawing, the control unit 64 pauses image recording on the recording paper P and detects the paper width of the recording paper Pn. The paper width detection (S433) is the same as the paper width detection process shown in FIG. That is, as shown in FIG. 21, in order to detect the left and right edges of the recording paper Pn after the scanning carriage 38 is moved so that the media sensor 50 is positioned at the center of the paper and the light quantity of the media sensor 50 is adjusted. From the center position shown in the figure, the scanning carriage 38 moves to the paper width detection start position (left side in the figure) that is outside the range of the recording paper P. Then, the scanning carriage 38 is moved to the right, and the AD value sequentially output from the media sensor 50 is stored in the RAM 67 in association with the encoder amount of the linear encoder 77 serving as the position information of the scanning carriage 38, and the AD value is stored. The left and right edges of the recording paper Pn are detected based on the above.

  The edge information obtained in this way is stored in the RAM 67 as that of the recording paper Pn on which image recording is to be performed next. As described above, when the sheet trailing edge detection flag is on and the sheet leading edge detection flag is on, the control unit 64 determines that the left and right edge positions based on the AD value detected by the media sensor 50 are the next image recording. It is determined that the recording paper Pn is to be used. Therefore, the control unit 64 stores the left and right edge information in the RAM 67 so as to be distinguishable from the edge information of the recording sheet P on which image recording is currently performed, as the recording sheet Pn on which image recording is to be performed next.

  Then, after the detection of the left and right ends of the recording paper Pn is completed, the control unit 64 performs image recording near the rear end of the recording paper P again. At this time, the edge information used for controlling the ink ejection of the recording head 39 uses the edge information of the recording paper P recorded in the RAM 67. Therefore, even after the left and right edges of the recording paper Pn are detected, borderless printing can be performed with high accuracy up to the rear edge of the recording paper P based on the left and right edge positions and the rear edge position of the recording paper P. Then, the print data to be recorded on the recording paper P is finished, and the image recording on the recording paper P is finished (S70).

  When the image recording on the recording paper P is completed, the control unit 64 turns off the paper trailing edge detection flag and the paper leading edge detection flag and stores them in the EEPROM 68 (S71). The next recording sheet Pn has already been fed (S80), and the left and right end positions in the vicinity of the front end position of the recording sheet Pn are stored in the RAM 67 as edge information of the recording sheet Pn ( In step S434, the recording paper Pn is conveyed by a predetermined conveyance amount (S40), and printing is performed by controlling the ink ejection of the recording head 39 based on the edge information corresponding to the recording paper Pn (S50). Thereby, borderless printing can be performed with high accuracy in accordance with the front end and left and right end positions of the recording paper Pn.

  As described above, according to the multifunction machine 1, end information based on the AD value of the media sensor 50 is stored in the RAM 67 in association with the recording paper P and the recording paper Pn, and corresponds to the recording papers P and Pn on which image recording is to be performed. Since the image recording is performed by the recording head 39 based on the edge information, the image recording can be accurately performed on the left and right edges of the recording sheets P and Pn.

Hereinafter, modifications of the above embodiment will be described.
In the above embodiment, as shown in FIG. 12, the center of the transport path 23 is the reference line L, and the center of the recording paper P is transported along the reference line L. 22, one end of the conveyance path 23 in the width direction is used as a reference line L, and one end of the recording paper P is conveyed along the reference line L.

  Then, the light amount adjustment (S302) in the sheet width detection process shown in the flowchart of FIG. 13 is not at the center position of the sheet as in S301, but inside the recording sheet P by a predetermined distance from the reference line L as shown in FIG. Perform at the position. When one end side of the recording paper P is conveyed as the reference line L, the recording paper P of all sizes always passes through the center side from the reference line L. Therefore, a position for adjusting the light amount of the media sensor 50 may be set within the range of the width W of the recording paper P of the minimum size on which image recording is performed, from the center of the reference line L.

  Further, the standby position (see FIG. 19) of the scanning carriage 38 in the case of performing the sheet trailing edge detection and the sheet leading edge detection shown in the flowchart in FIG. That is, since recording paper P of all sizes is conveyed with one end thereof aligned with the reference line L, the one end side is set as a standby position, and the recording paper Pn is related to the size of the recording paper Pn on which image recording is performed next. Accordingly, it is possible to reliably detect the front end of the recording paper Pn while keeping the standby position of the scanning carriage 38 constant.

FIG. 1 is a perspective view showing an external configuration of a multifunction machine 1 according to an embodiment of the present invention. FIG. 2 is a longitudinal sectional view showing the internal configuration of the multifunction machine 1. FIG. 3 is an enlarged cross-sectional view showing the main configuration of the printer unit 2. FIG. 4 is an enlarged view showing the configuration of the registration sensor 33. FIG. 5 is a schematic plan view showing the configuration around the scanning carriage 38. FIG. 6 is a bottom view showing the configuration of the bottom surface of the scanning carriage 38. FIG. 7 is a partial cross-sectional view showing an outline of a cross-sectional configuration of the media sensor 50. FIG. 8 is a schematic cross-sectional view showing the internal configuration of the recording head 30. FIG. 9 is a block diagram illustrating a configuration of the control unit 64 of the multifunction machine 1. FIG. 10 is a flowchart showing the printing operation of the multifunction device 1. FIG. 11 is a schematic diagram illustrating a conveyance state of the recording paper P. FIG. 12 is a plan view showing the position of the media sensor 50 in the light amount adjustment. FIG. 13 is a flowchart showing the paper width detection process. FIG. 14 is a graph showing the relationship between the AD value obtained by the media sensor 50 and the paper edge position. FIG. 15 is a schematic diagram illustrating a conveyance state of the recording paper P. FIG. 16 is a flowchart showing the conveyance process. FIG. 17 is a flowchart showing the printing process. FIG. 18 is a schematic diagram illustrating a conveyance state of the recording paper P and the recording paper Pn. FIG. 19 is a plan view showing the standby position of the scanning carriage 38 in detecting the trailing edge of the paper. FIG. 20 is a plan view showing the standby position of the scanning carriage 38 in detecting the front edge of the sheet. FIG. 21 is a plan view showing the position of the scanning carriage 38 in detecting the paper width of the recording paper Pn. FIG. 22 is a plan view showing the light amount adjustment position of the media sensor 50 in the modified example.

1 ... Multifunction machine (image recording device)
25: Paper feed roller (conveying means)
33 ... Registration sensor (recording medium detection means)
38... Scanning carriage 39... Recording head 50... Media sensor (edge detection means)
51... Light emitting section 52... Light receiving section 60.
62... Discharge roller (conveying means)
64... Control unit (control means, end detection means)

Claims (7)

A conveying means for conveying a recording medium to be image-recorded next in the conveying direction before the image recording of the recording medium currently performing image recording ;
A recording head for recording an image on a recording medium;
In addition to the recording head, a sensor capable of detecting the presence or absence of the recording medium is mounted upstream of the recording head in the transport direction of the recording medium and at one end in the scanning direction of the scanning carriage. A scanning carriage that reciprocates in a scanning direction orthogonal to the conveyance direction of the recording medium;
In borderless printing, left and right edge detecting means for moving the scanning carriage and detecting left and right edges in the scanning direction of the recording medium based on a detection signal from the sensor;
In borderless printing, after the scanning carriage is scanned in the scanning direction and image recording is performed by the recording head , the recording head is outside the left and right ends of the recording medium, and the sensor is the recording medium. The scanning carriage is made to wait at a standby position inside the left and right ends of the recording medium, and the recording medium is conveyed based on a detection signal output from the sensor when the conveying means conveys the recording medium with a predetermined line feed width. Front and rear end detecting means for detecting front and rear ends in the direction;
In borderless printing, the left and right edge information indicating the left and right edge positions of the recording medium detected by the left and right edge detecting means is associated with the recording medium that is currently recording an image and the recording medium that is next recording an image. Storage means for storing
In borderless printing, the front and rear end detection means detects the rear end of the recording medium on which image recording is currently performed, and then detects the front end of the recording medium on which image recording is to be performed next . The image recording is stopped, the scanning carriage is moved, the left and right ends in the scanning direction of the recording medium are detected based on the detection signal from the sensor, and the recording medium associated with the left and right end information is the next image recording. Recording medium determination means for determining that the recording medium should be performed,
In borderless printing, an image recording apparatus comprising: a control unit that controls an image recording operation of the recording head on each recording medium based on left and right edge information stored in the storage unit. The image recording apparatus according to claim 1 , wherein the front and rear end detection means determines a standby position of the scanning carriage based on the left and right end information. The transport means transports the recording medium such that one of the left and right ends of the recording medium passes on a reference line along the transport direction, and the front and rear end detection means includes the reference line of the recording medium. The image recording apparatus according to claim 1, wherein one end side on the side is set as the standby position. A recording medium detection means for detecting the passage of the recording medium upstream of the scanning carriage in the transport direction;
The front / rear end detecting means waits for the front and rear of the recording medium by waiting the scanning carriage at a standby position after the recording medium detecting means detects that the recording medium on which image recording is currently finished has passed. The image recording apparatus according to claim 1 , wherein the image recording apparatus detects an end. The recording head performs image recording of a recording medium on which image recording is currently performed within a range up to the rear end position of the recording medium detected by the front and rear end detection means, and then performs image recording 5. The image recording apparatus according to claim 1 , wherein the image recording on the recording medium is performed within a range after the front end position of the recording medium detected by the front and rear end detecting means. The image recording apparatus according to claim 1 , wherein the sensor includes a light emitting unit that irradiates light to the recording medium and a light receiving unit that receives reflected light from the recording medium. . The image recording according to claim 6 , wherein the left and right edge detection means and the front and rear edge detection means detect the edge of the recording medium based on whether or not the amount of light received by the light receiving unit exceeds a threshold value. apparatus.

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