JP2009078377A - Cleaning method of platen for inkjet recorder and inkjet recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a means which can remove an ink adhered to a platen top surface between a pair of fixed supports prepared separately in a conveyance direction of a sheet. <P>SOLUTION: The cleaning method of a platen 42 includes a step (S2) and a step (S3). In the step (S2), a movable rib 121 moves to an upstream side or a downstream side of the conveyance direction in the platen 42 where the first fixed support 102 and the second fixed support 103 projecting from the top surface 109 are prepared separately in the conveyance direction, and where the movable rib 121 moves back and forth in the conveyance direction between the first fixed support 102 and the second fixed support 103 projecting from the top surface 109. In the step (S3), a cleaning sheet 197 capable of absorbing the ink is fed to the platen 42, and a front end or a rear end of the cleaning sheet 197 is hung down to between the first fixed support 102 and the second fixed support 103, whereby the front end or rear end of the cleaning sheet 197 comes in touch with the top surface 109. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a platen cleaning method for an inkjet recording apparatus and an inkjet recording apparatus that remove ink droplets selectively ejected from a recording head from the platen.

  2. Description of the Related Art Conventionally, an ink jet type image recording apparatus (hereinafter also referred to as “ink jet recording apparatus”) that records an image on a recording paper (recording medium) using ink is known. This ink jet recording apparatus includes an ink jet recording head, and selectively ejects ink droplets from a nozzle of the recording head toward a recording paper. The ink droplets land on the recording paper, whereby a desired image is recorded on the recording paper. In an ink jet recording apparatus, a plurality of recording sheets are stored in a box-shaped or tray-shaped space called a sheet feeding cassette or a sheet feeding tray, and are fed immediately below the recording head when image recording is performed. The A platen for an ink jet recording apparatus (hereinafter also referred to as “platen”) is provided immediately below the recording head, and the recording paper is supported by the platen so as to face the recording head.

  As the accuracy of image recording is improved, ink droplets ejected from the recording head become minute, and as a result, a phenomenon may occur in which minute ink droplets that have not landed on the recording paper float. This floating ink droplet is called ink mist. This ink mist can adhere to the peripheral member of the recording head including the platen. Also, this is particularly noticeable when image recording is performed without providing a margin on the edge of the recording paper. Among the ink droplets ejected from the recording head, the ink that does not land on the recording paper and land on the platen as it is. There can be drops. When ink droplets adhere to the platen in this way, the ink droplets adhere (transfer) to the recording paper fed thereafter, causing problems such as contamination of the recording paper and degradation of the recorded image. In order to remove such stains on the platen, cleaning using a dedicated sheet and cleaning using plain paper have been proposed (see Patent Document 1).

  Further, by providing a pair of ribs protruding from the upper surface of the platen on the upstream side and the downstream side of the image recording area by the recording head, a groove that does not contact the recording paper is formed between the pair of ribs. There has been proposed a configuration in which a movable rib that slides in the recording sheet conveyance direction is provided (see Patent Document 2). According to this configuration, since the ink droplets ejected from the recording head land in the groove between the pair of ribs, the ink droplets adhering to the platen are prevented from adhering to the recording paper.

Japanese Patent Laid-Open No. 2004-25666 JP 2007-175971 A

  However, even in the configuration described in Patent Document 2, when an ink droplet that has landed in a groove between a pair of ribs is left unattended, other ink droplets or ink mist grows on the ink droplet and grows large. Ink drops. Then, there is a risk that the ink droplets will contaminate the recording paper passing over the groove. On the other hand, in the cleaning method described in Patent Document 1, even if it is possible to remove the ink attached to the upper surfaces of the pair of ribs, it is not possible to remove the ink attached to the groove between the pair of ribs. Can not.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide ink attached to the upper surface of the platen between a pair of fixed support portions provided to be separated in the sheet conveyance direction. It is to provide means that can be removed.

  (1) In the method for cleaning a platen for an ink jet recording apparatus according to the present invention, a pair of fixed support portions protruding from the upper surface are provided apart from each other in the sheet conveyance direction, and the pair of fixed support portions protrudes from the upper surface. In the platen provided with a movable support portion that reciprocates in the transport direction between the first step in which the movable support portion moves upstream or downstream in the transport direction, and a sheet capable of absorbing ink A second step of feeding the platen to the platen and hanging the leading edge or the trailing edge of the sheet between the pair of fixed support portions so that the leading edge or the trailing edge of the sheet contacts the upper surface.

  In the first step, when the movable support portion moves to the upstream side or the downstream side in the transport direction, the leading end or the rear end of the sheet supported by only one of the pair of fixed support portions is between the pair of fixed support portions. It becomes possible to sag. In the second step, when the sheet is fed to the platen, the leading edge or the trailing edge of the sheet hangs between the pair of fixed support portions and comes into contact with the upper surface of the platen. Since the sheet can absorb ink, the ink remaining on the upper surface of the platen is absorbed by the leading end portion or the trailing end portion of the sheet. Thereby, the ink remaining on the upper surface of the platen is removed.

  (2) In the present invention, the front or rear end of the sheet slides relative to the upper surface by reciprocating the sheet in the transport direction in a state where the front or rear end of the sheet is in contact with the upper surface. It may further include a third step.

  In the second step, after the leading edge or trailing edge of the sheet comes into contact with the upper surface of the platen, in the third step, the sheet is reciprocated in the transport direction, and the leading edge or trailing edge of the sheet slides on the upper surface of the platen. Thereby, the residual ink in the range in which the sheet slides is absorbed by the sheet and removed.

  (3) In the present invention, the movable support portion is moved to the vicinity of the center between the pair of fixed support portions to separate the front end or the rear end of the sheet from the upper surface, and then the movable support portion is moved for a predetermined drying time. It may further include a fourth step in which the support unit waits and the conveyance of the sheet is stopped.

  In the fourth step, the movable support portion moves to near the center between the pair of fixed support portions and stands by, so that the sheet is supported by the movable support portion, and the leading end or the rear end of the sheet is separated from the upper surface of the platen. Is done. The time for which the movable support unit waits is set as a predetermined drying time. During this drying time, the conveyance of the sheet is stopped. Therefore, the sheet is stopped while being supported by the movable support portion. The drying time is the time required for the ink absorbed by the leading edge or trailing edge of the sheet to dry. When the drying time elapses, the leading edge or the trailing edge of the sheet is dried, so that even if the sheet is subsequently conveyed, ink does not adhere to the movable support portion or the like.

  (4) The present invention may further include a fifth step of bending and deforming the leading edge or the trailing edge of the sheet in a bending direction in contact with the upper surface before feeding the sheet to the platen. .

  Thereby, there exists an advantage that it becomes easy to hang | hang a sheet | seat between a pair of fixed support parts.

  (5) In the fifth step, the sheet may be curved and deformed in the fifth step by conveying the sheet to a curved conveyance path communicating with the platen and temporarily stopping conveyance of the sheet in the conveyance path. Good.

  Thereby, the sheet can be easily curved and deformed.

  (6) The present invention may further include a sixth step of ejecting ink droplets from the recording head to the sheet and performing pin check or test printing of the recording head.

  Thereby, areas other than the upper end part or the lower end part of the sheet can be effectively used. In addition, since the platen cleaning and the pin check or test printing can be performed at the same time, the time required for maintenance is shortened.

  (7) An ink jet recording apparatus according to the present invention includes a recording head that selectively ejects ink droplets, a platen whose upper surface is arranged to face the recording head, a protrusion protruding from the platen toward the recording head, and A pair of fixed support portions separated in the sheet conveyance direction, a movable support portion projecting from the platen toward the recording head and reciprocating between the pair of fixed support portions in the conveyance direction, and the platen When a sheet transporting mechanism for transporting a sheet and a sheet capable of absorbing ink by the transport mechanism are fed to the platen, the leading end or the trailing end of the sheet hangs down between the pair of fixed support portions, and the platen And a drive mechanism that moves the movable support portion to the upstream side or the downstream side in the transport direction so as to come into contact with the upper surface.

  Part of the ink ejected from the recording head floats as ink mist and adheres to the upper surface of the platen. When ink mist adhering to the upper surface of the platen grows, ink droplets are formed. These ink droplets cause the recording medium to become dirty as residual ink. In order to remove such residual ink, a sheet capable of absorbing ink is fed onto the platen by the transport mechanism. In that case, a drive mechanism moves a movable support part to the upstream or downstream of a conveyance direction. Thereby, the front-end | tip or the rear end of the sheet | seat supported only in any one of a pair of fixed support part can sag between a pair of fixed support parts. When the sheet is fed to the platen, the leading edge or trailing edge of the sheet hangs between the pair of fixed support portions and comes into contact with the upper surface of the platen, and the ink remaining on the upper surface of the platen is removed from the leading edge or trailing edge of the sheet. Absorbed into the part. Thereby, the ink remaining on the upper surface of the platen is removed.

  (8) The drive mechanism may reciprocate the sheet in the transport direction in a state where the leading end or the trailing end of the sheet is in contact with the upper surface.

  When the sheet is reciprocated in the conveyance direction, the leading edge or the trailing edge of the sheet slides on the upper surface of the platen. Thereby, the residual ink in the range in which the sheet slides is absorbed by the sheet and removed.

  (9) The drive mechanism moves the movable support portion to the vicinity of the center between the pair of fixed support portions and separates the front end or the rear end of the sheet from the upper surface, and then the predetermined drive time. The movable support unit may be on standby, and the transport mechanism may stop the transport of the sheet for the drying time.

  When the movable support portion is moved to the vicinity of the center between the pair of fixed support portions, the sheet hanging between the pair of fixed support portions is supported by the movable support portion, and the leading end or the rear end of the sheet is the platen. Separate from the top surface. The time for which the movable support unit waits is set as a predetermined drying time. During this drying time, the conveyance mechanism stops conveying the sheet. Therefore, the sheet is stopped while being supported by the movable support portion. The drying time is the time required for the ink absorbed by the leading edge or trailing edge of the sheet to dry. When the drying time elapses, the leading edge or trailing edge of the sheet is dried, so that even if the sheet is subsequently conveyed, ink does not adhere to the movable support portion or the conveyance mechanism.

  (10) The present invention further includes a conveyance path that leads to the platen and has a curved portion that curves in a bending direction in which the leading edge or the trailing edge of the sheet contacts the upper surface of the platen, and the conveyance mechanism includes the sheet When the leading edge or the trailing edge of the sheet passes through the curved portion, the conveyance of the sheet may be temporarily stopped.

  When the conveyance of the sheet is temporarily stopped when the leading end or the trailing end of the sheet passes through the bending portion, the sheet is bent and deformed along the bending portion. Since the direction of the curved deformation is a direction in which the leading end or the trailing end of the sheet is in contact with the upper surface of the platen, there is an advantage that the sheet fed onto the platen is likely to hang down between the pair of fixed support portions.

  (11) The recording head may perform pin check or test printing on the sheet.

  Thereby, areas other than the upper end part or the lower end part of the sheet can be effectively used. In addition, since the platen cleaning and the pin check or test printing can be performed at the same time, the time required for maintenance is shortened. Pin check is a process of ejecting ink droplets from each nozzle to a sheet at a predetermined timing, and determining ejection failure of each nozzle (pin) of the recording head that ejects ink droplets based on an image recorded on the sheet. To do. In the test printing, characters and images set in advance as test patterns are recorded on a sheet, and recording failure is determined based on the recording result.

  According to the present invention, the movable support portion moves to the upstream side or the downstream side in the transport direction, and the front end or the rear end of the sheet supported only by one of the pair of fixed support portions is the pair of fixed support portions. Since the sheet sag between the upper surface and the upper surface of the platen, the sheet absorbs ink remaining on the upper surface of the platen and removes the ink. Thereby, the space between the pair of fixed support portions can be cleaned.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings as appropriate. In addition, this embodiment is only an example of this invention and can be suitably changed in the range which does not change the summary of this invention.

[Explanation of drawings]
FIG. 1 is an external perspective view of a multifunction machine 10 according to an embodiment of the present invention. FIG. 2 is a longitudinal sectional view showing the internal configuration of the multifunction machine 10. FIG. 3 is a partially enlarged cross-sectional view showing the main configuration of the printer unit 11. FIG. 4 is a plan view showing the main part of the printer unit 11. FIG. 5 is a perspective view showing the main part of the printer unit 11. FIG. 6 is a block diagram illustrating a configuration of the control unit 64 of the multifunction machine 10. FIG. 7 is an enlarged perspective view of the platen 42 and the drive mechanism 105. FIG. 8 is an enlarged perspective view of the movable support portion 88. FIG. 9 is an enlarged perspective view of the movable support portion 88 viewed from the bottom surface side of the platen 42. FIG. 10 is an enlarged perspective view of the drive mechanism 105. FIG. 11 is an enlarged perspective view of the rotating plate 125. FIG. 12 is a bottom view of the rotating plate 125. FIG. 13 is a timing chart showing the timing of conveying the recording paper and sliding the movable support portion 88 when borderless recording is performed. In FIG. 13, the horizontal axis indicates the passage of time, lines 167 and 173 indicate the displacements of the positions of the leading and trailing ends of the recording paper being conveyed, and the line 170 indicates the position of the movable support 88. The displacement is shown. Further, in FIG. 13, a diagram 169 and a diagram 168 respectively show the displacement of the contact member 158 and the drive timing of the LF motor 71. FIG. 14 is a diagram illustrating the displacement of the movable support portion 88 in the order of (a) to (d) during conveyance of the recording paper. In FIG. 14, the direction of the arrow 166 is the conveyance direction of the recording paper. FIG. 14 shows the operation timing from when the recording paper is registered by the conveyance roller 60 (see FIG. 3) to when the recording on the recording paper is finished, and is fed from the paper feed tray 20. The operation until the recording paper reaches the conveyance roller 60 is omitted. FIG. 15 is a diagram showing the positional relationship between the recording paper and the movable support portion 88 in borderless recording. FIG. 16 is a timing chart showing the timing of conveying the cleaning sheet 197 and sliding the movable support 88 when cleaning is performed. In FIG. 16, the horizontal axis indicates the passage of time, lines 188 and 192 indicate the displacements of the positions of the front and rear ends of the cleaning sheet 197 being conveyed, respectively, and lines 190 and 195 are The displacement of the movable rib 121 is shown. In FIG. 16, diagrams 189, 191, 193, 194, and 196 indicate the displacement of the contact member 158 and the driving timing of the LF motor 71, respectively. 17 and 18 are diagrams showing the positional relationship between the cleaning sheet 197 and the movable rib 121 in cleaning.

[Schematic configuration of MFP 10]
The multifunction machine 10 is a multi-function device (MFD) having a printer unit 11 and a scanner unit 12, and has a print function, a scan function, a copy function, and a facsimile function. The printer unit 11 of the multifunction machine 10 corresponds to the ink jet recording apparatus according to the present invention. Therefore, functions other than the printer function in the multifunction machine 10 are arbitrary, and the inkjet recording apparatus according to the present invention may be implemented as a single-function printer in which the scanner unit 12 is omitted, for example.

  The printer unit 11 of the multifunction machine 10 can be connected mainly to an external information device such as a computer or a digital camera. Based on print data including image data and document data transmitted from an external information device, the printer unit 11 records an image or document on a recording sheet as a recording medium. The multi-function device 10 can be loaded with various storage media such as a card-type memory. It is also possible for the printer unit 11 to record an image on a recording sheet based on the image data stored in the storage medium.

  As shown in FIG. 1, the outer shape of the multifunction machine 10 is a wide, thin, substantially rectangular parallelepiped whose width and depth are larger than the height. The lower part of the multifunction machine 10 is a printer unit 11. The multifunction machine 10 has an opening 13 on the front side. Inside the opening 13, a paper feed tray 20 and a paper discharge tray 21 are provided in two upper and lower stages. A plurality of recording sheets are held in the sheet feeding tray 20. At the time of image recording, the recording paper held in the paper feed tray 20 is fed into the printer unit 11 to record a desired image, and the recording paper after image recording is discharged to the paper discharge tray 21.

  The upper part of the multifunction machine 10 is a scanner unit 12. Although the scanner unit 12 is configured as a so-called flatbed scanner, the configuration of the scanner unit 12 is not directly related to the present invention, and thus detailed description thereof is omitted.

  An operation panel 15 is provided on the front upper portion of the multifunction machine 10. The operation panel 15 is a device for operating the printer unit 11 and the scanner unit 12 and includes various operation buttons and a liquid crystal display unit. The multifunction machine 10 operates based on an operation instruction from the operation panel 15. When the multifunction device 10 is connected to an external information device, the multifunction device 10 also operates based on an instruction transmitted from the external information device via a printer driver or a scanner driver. In addition, a slot portion 16 is provided in the upper left part of the front surface of the multifunction machine 10 (see FIG. 1). A card-type memory card is inserted into the slot portion 16 so that data can be read and written.

[Schematic Configuration of Printer Unit 11]
Hereinafter, a schematic configuration of the printer unit 11 will be described. As shown in FIG. 2, a paper feed tray 20 is disposed on the bottom side of the multifunction machine 10. The paper feed tray 20 can hold recording paper of A4 size or smaller. However, if a slide tray is provided in the paper feed tray 20 so that the tray surface can be enlarged, a recording paper larger than A4 size can be held in the paper feed tray 20.

  A separation plate 22 is provided on the back side of the paper feed tray 20. The upper end of the separation plate 22 is tilted toward the back side of the printer unit 11. The separation sheet 22 separates the recording paper that is double-fed from the paper feed tray 20 and guides the separated uppermost recording paper upward.

  The paper discharge tray 21 is arranged in two upper and lower stages above the paper feed tray 20. The paper discharge tray 21 holds recording paper after image recording in a stacked state. The recording paper can be conveyed from the paper feed tray 20 to the paper discharge tray 21 through a paper conveyance path 23 described later. Image recording is performed by the image recording unit 24 in the process of transporting the recording paper.

  As shown in FIG. 3, a paper feed roller 25 is provided above the paper feed tray 20. The paper feed roller 25 supplies the recording paper stacked on the paper feed tray 20 to the paper transport path 23. The paper feed roller 25 is supported at the tip of the arm 26. The sheet feed roller 25 is driven and rotated by a drive transmission mechanism 27 provided along the arm 26 with the LF motor 71 (see FIG. 6) as a drive source. In the drive transmission mechanism 27, a plurality of gears are engaged with each other, and the rotation of each gear is sequentially transmitted to transmit the drive of the motor 71 to the paper feed roller 25.

  The base end portion of the arm 26 is supported by the base shaft 28, and the arm 26 can rotate about the base shaft 28. By the rotation of the arm 26, the paper feed roller 25 moves up and down so as to be able to contact and separate from the paper feed tray 20. The arm 26 is elastically biased downward by its own weight or biased by a spring or the like. For this reason, the arm 26 normally rotates toward the paper feed tray 20 and is pushed upward by the paper feed tray 20 when the paper feed tray 20 is inserted and removed. When the arm 26 is rotated downward by elastic bias, the paper feed roller 25 is pressed against the recording paper on the paper feed tray 20. In this state, when the paper feeding roller 25 is rotated, the uppermost recording paper is sent out to the separation plate 22 by the frictional force between the roller surface of the paper feeding roller 25 and the recording paper. The leading edge of the recording sheet abuts on the separation plate 22 and is guided upward, and is fed into the sheet conveyance path 23. 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 by the action of friction or static electricity, but this recording paper is restrained by contact with the separation plate 22. The

  The sheet conveyance path 23 is formed as a so-called U-turn path extending upward from the upper side of the separation plate 22 in the sheet feeding tray 20 to the front side of the apparatus. A portion of the U-turn path that is curved on the back side of the apparatus is referred to as a curved portion 17 in this specification. The paper conveyance path 23 is partitioned and formed by an outer guide surface and an inner guide surface, except for a portion where the image recording unit 24 and the like are disposed. For example, the bending portion 17 is configured by arranging an outer guide member 18 and an inner guide member 19 to face each other and fixing them to the apparatus frame. The outer guide member 18 constitutes an outer guide surface, and the inner guide member 19 constitutes an inner guide surface. The bending portion 17 is provided with a rotating roller 29. The rotating roller 29 is freely rotatable. The roller surface of the rotary roller 29 is exposed from the outer guide surface into the sheet conveyance path 23. Therefore, the rotary roller 29 can come into contact with the recording surface side of the recording paper (the surface facing the recording head 39). As the rotary roller 29 rotates while contacting the recording paper, the recording paper is smoothly conveyed in the bending portion 17.

[Image recording unit 24]
As shown in FIG. 3, the image recording unit 24 is disposed on the downstream side in the transport direction from the curved portion 17 in the paper transport path 23. The image recording unit 24 includes a carriage 38 and an ink jet recording head 39. The recording head 39 is mounted on the carriage 38. The carriage 38 reciprocates in a horizontal direction perpendicular to the recording sheet conveyance direction. Although not appearing in FIG. 3, an ink cartridge is disposed inside the multifunction device 10 independently of the recording head 39. Cyan (C), magenta (M), yellow (Y), and black (Bk) inks are supplied from the ink cartridge to the recording head 39 through the ink tube 41 (see FIG. 4).

  Although not shown in each figure, the recording head 39 has a plurality of nozzles on its lower surface. The nozzles are arranged in one row in the recording sheet conveyance direction corresponding to the respective color inks of C, M, Y, and Bk. The ink droplets of each color ink are ejected from each nozzle by the vibration of the piezo element provided in each nozzle. While the carriage 38 is reciprocated, each color ink is selectively ejected from the recording head 39 as fine ink droplets. As a result, an image is recorded on the recording paper conveyed on the platen 42. Note that the pitch and number of each nozzle in the transport direction are appropriately set according to the resolution of the recorded image. The number of nozzle rows corresponding to each color is increased or decreased according to the number of types of color ink.

  As shown in FIGS. 4 and 5, a pair of guide rails 43 and 44 are arranged on the upper side of the sheet conveyance path 23. The guide rails 43 and 44 are separated from each other by a predetermined distance in the recording sheet conveyance direction (the direction from the upper side to the lower side in FIG. 4), and perpendicular to the recording sheet conveyance direction (left and right direction in FIG. 4). Are arranged in the longitudinal direction. The guide rails 43 and 44 are provided in the casing of the printer unit 11 and constitute a part of a frame that supports each member constituting the printer unit 11.

  The guide rail 43 disposed on the upstream side in the recording sheet conveyance direction has a substantially flat plate shape. The length of the guide rail 43 in the longitudinal direction (left-right direction in FIG. 4) is set longer than the reciprocating range of the carriage 38. The guide rails 44 disposed on the downstream side in the recording paper conveyance direction are also substantially flat, and the length in the longitudinal direction is the same as the length of the guide rails 43. Further, the edge 45 on the upstream side in the conveying direction of the guide rail 44 is bent at a substantially right angle upward.

  The carriage 38 is disposed so as to straddle the guide rails 43 and 44. That is, the end of the carriage 38 on the upstream side in the transport direction is placed on the guide rail 43, and the end of the carriage 38 on the downstream side in the transport direction is placed on the guide rail 44. Although not shown in each drawing, the carriage 38 sandwiches the edge 45 of the guide rail 44 by a pair of rollers. As a result, the carriage 38 is positioned with respect to the recording paper conveyance direction and is slidable in the longitudinal direction of the guide rails 43 and 44, that is, in a direction orthogonal to the recording paper conveyance direction. During the sliding, the roller pair slides along the edge 45 while rotating.

  A belt drive mechanism 46 is disposed on the upper surface of the guide rail 44. The belt drive mechanism 46 includes a drive pulley 47, a driven pulley 48, and an endless annular timing belt 49. The drive pulley 47 and the driven pulley 48 are respectively arranged near both ends in the longitudinal direction of the guide rail 44. The timing belt 49 is bridged between the driving pulley 47 and the driven pulley 48. A plurality of teeth are provided inside the timing belt 49, and these teeth mesh with the teeth of the drive pulley 47. The drive pulley 47 is rotationally driven by a CR motor 73 (see FIG. 5). The rotation of the drive pulley 47 is transmitted and the timing belt 49 moves in a circumferential direction.

  The carriage 38 is connected to a timing belt 49. Accordingly, the carriage 38 reciprocates on the guide rails 43 and 44 based on the circumferential motion of the timing belt 49. Since the recording head 39 is mounted on the carriage 38 as described above, the recording head 39 reciprocates in a direction orthogonal to the recording sheet conveyance direction as the carriage 38 reciprocates.

  As shown in FIG. 4, the encoder strip 50 of the linear encoder 77 (see FIG. 6) is disposed on the guide rail 44. The encoder strip 50 is formed in a strip shape, and light transmitting portions and light shielding portions are alternately arranged at a predetermined pitch along the longitudinal direction thereof. The encoder strip 50 is supported by support portions 33 and 34 provided at both ends of the guide rail 44 in the longitudinal direction, and is disposed on the upper side of the guide rail 44 so as to extend in the longitudinal direction. An optical sensor 35 that is a transmission type sensor is provided on the upper surface of the carriage 38. The optical sensor 35 is disposed corresponding to the encoder strip 50 and detects the pattern of the encoder strip 50 when the carriage 38 reciprocates. The detection signal of the optical sensor 35 is output as a pulse signal from a head control board (not shown) mounted on the carriage 38. Based on this pulse signal, the moving direction and speed of the carriage 38 are calculated, and the reciprocation of the carriage 38 is controlled. In FIG. 5, the encoder strip 50, the support portions 33 and 34, and the optical sensor 35 are omitted.

  A platen 42 is disposed below the guide rails 43 and 44 so as to face the recording head 39. The platen 42 is disposed so as to occupy the central portion through which the recording paper passes in the reciprocating range of the carriage 38. The width of the platen 42 is set sufficiently larger than the maximum width of the recording paper that can be conveyed by the printer unit 11. Therefore, both ends in the width direction of the recording sheet to be conveyed always pass over the platen 42. As will be described in detail later, the platen 42 is provided with a movable support portion 88 (see FIG. 5). The movable support portion 88 is slidable in the recording sheet conveyance direction.

  As shown in FIG. 4, maintenance units such as a purge mechanism 51 and a waste ink tray 84 are disposed on both sides of the platen 42. The purge mechanism 51 is for sucking and removing bubbles and foreign matters from the nozzles of the recording head 39. The waste ink tray 84 is for receiving an empty jet of ink from the recording head 39 called flushing. In FIG. 5, the purge mechanism 51 is omitted.

  As shown in FIG. 4, the ink tube 41 is a tube made of synthetic resin, and has elasticity that bends following the reciprocation of the carriage 38. Four ink tubes 41 are provided corresponding to each color ink of CMYK. One end of each ink tube 41 is connected to the ink cartridge, and ink flowing out from the ink cartridge flows through each ink tube 41. Each ink tube 41 is pulled out to the vicinity of the center along the width direction of the apparatus, a part of which is fixed to the fixing clip 36 of the apparatus main body, and the other end is connected to the recording head 39. The portion of each ink tube 41 from the fixed clip 36 to the carriage 38 is not fixed to the apparatus main body or the like, and this portion changes its posture following the reciprocation of the carriage 38. In FIG. 4, the ink tube 41 extending from the fixed clip 36 toward the cartridge mounting portion is omitted. In FIG. 5, the ink tube 41 is omitted.

  Transmission of a recording signal or the like from the main board constituting the control unit 64 (see FIG. 6) to the head control board of the recording head 39 is performed through the flat cable 85. The flat cable 85 electrically connects the main board and the head control board. The main board is disposed on the front side of the apparatus (the lower side of the paper in FIG. 4) and is not shown in FIG. The flat cable 85 is a thin ribbon in which a plurality of conductive wires that transmit electrical signals are covered with a synthetic resin film such as a polyester film and insulated. Similarly to the ink tube 41, the flat cable 85 has elasticity that bends following the reciprocation of the carriage 38.

[Transport mechanism]
The transport mechanism for transporting the recording paper is composed mainly of the transport roller 60 and the pinch roller, the paper discharge roller 62 and the spur 63 in addition to the paper feed roller 25 described above.

  As shown in FIG. 3, a pair of conveying rollers 60 and a pinch roller are provided on the upstream side of the image recording unit 24 in the conveying direction. In FIG. 3, the pinch roller does not appear hidden behind other members, but the pinch roller is disposed so as to be in pressure contact with the lower side of the conveying roller 60. The transport roller 60 and the pinch roller sandwich the recording paper transported through the paper transport path 23 and transport it onto the platen 42.

  A pair of paper discharge rollers 62 and a spur 63 are provided on the downstream side of the image recording unit 24 in the transport direction. The paper discharge roller 62 and the spur 63 hold the recorded recording paper and convey it to the paper discharge tray 21. The transport roller 60 and the paper discharge roller 62 are rotated in synchronization with the driving force transmitted from the LF motor 71. The conveyance roller 60 and the discharge roller 62 are intermittently driven, so that the recording paper is intermittently conveyed with a predetermined line feed width. A rotary encoder 76 (see FIG. 6) provided corresponding to the transport roller 60 detects the pattern of the encoder disk 61 that rotates together with the transport roller 60 with an optical sensor 82 (see FIG. 5). Based on this detection signal, the rotation of the transport roller 60 and the paper discharge roller 62 is controlled.

  The spur 63 is provided so as to be slidable in a direction in which the spur 63 contacts and separates from the paper discharge roller 62. The spur 63 is urged so as to be in pressure contact with the paper discharge roller 62 by a coil spring. When the recording paper enters between the paper discharge roller 62 and the spur 63, the spur 63 retreats against the biasing force of the coil spring by the thickness of the recording paper and presses the recording paper against the paper discharge roller 62. Thereby, the rotational force of the paper discharge roller 62 is reliably transmitted to the recording paper. The pinch roller is also provided in the same manner with respect to the conveying roller 60. Therefore, the recording sheet is urged by the pinch roller and pressed against the conveying roller 60, whereby the rotational force of the conveying roller 60 is reliably transmitted to the recording sheet.

  A registration sensor 95 is disposed on the upstream side of the conveyance roller 60 in the sheet conveyance path 23. The registration sensor 95 is a so-called mechanical sensor having a detector and an optical sensor not shown in FIG. The detector of the registration sensor 95 has a lever shape protruding so as to penetrate the paper conveyance path 23, and appears and disappears in the paper conveyance path 23 by turning. The detector is elastically urged by the spring material and always protrudes to the paper conveyance path 23. When the recording paper conveyed through the paper conveyance path 23 abuts, the detector rotates against the elastic urging to convey the paper. Retreat from the road 23. The registration sensor 95 detects such rotation of the detector by an optical sensor and outputs it as an electrical signal. Based on the electrical signal output from the registration sensor 95, it is determined that the leading edge or the trailing edge of the recording paper has passed the position of the detector.

[Control unit 64]
The control unit 64 controls the overall operation of the multifunction machine 10 including not only the printer unit 3 but also the scanner unit 2, and is configured by a main board to which the above-described flat cable 85 is connected. Note that the configuration related to the control of the scanner unit 12 is not the main configuration of the present invention, and thus detailed description thereof is omitted.

  As shown in FIG. 6, the control unit 64 mainly includes a CPU (Central Processing Unit) 65, a ROM (Read Only Memory) 66, a RAM (Random Access Memory) 67, and an EEPROM (Electrically Erasable and Programmable ROM) 68. It is configured as a microcomputer. The control unit 64 is connected to an ASIC (Application Specific Integrated Circuit) 70 via a bus 69.

  The ROM 66 stores a program for controlling various operations of the multifunction machine 10 and the like. 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 EEPROM 68 stores settings and flags that should be retained even after the power is turned off.

  The ASIC 70 generates a phase excitation signal for energizing the LF motor 71 in accordance with a command from the CPU 65. This signal is applied to the drive circuit 72 of the LF motor 71, and the drive signal is energized to the LF motor 71 via the drive circuit 72. In this way, rotation control of the LF motor 71 is performed. The LF motor 71 is a drive source for the transport roller 60 and the paper discharge roller 62, and is also a drive source for the paper feed roller 25.

  The drive circuit 72 drives the LF motor 71 at a desired rotation. The drive circuit 72 receives an output signal from the ASIC 70 and forms an electric signal for rotating the LF motor 71. In response to this electrical signal, the LF motor 71 rotates. The rotation of the LF motor 71 is transmitted to the paper feed roller 25, the transport roller 60, the paper discharge roller 62, and the like.

  The ASIC 70 generates a phase excitation signal for energizing the CR motor 73 in accordance with a command from the CPU 65. This signal is applied to the drive circuit 74 of the CR motor 73, and the drive signal is energized to the CR motor 73 via the drive circuit 74. In this way, rotation control of the CR motor 73 is performed.

  The drive circuit 74 drives the CR motor 73 with a desired rotation. The drive circuit 74 receives an output signal from the ASIC 70 and forms an electric signal for rotating the CR motor 73. Upon receipt of this electric signal, the CR motor 73 rotates. The rotational force of the CR motor 73 is transmitted to the carriage 38 via the belt drive mechanism 46, and thereby the carriage 38 is reciprocated. In this way, the reciprocation of the carriage 38 is controlled by the control unit 64.

  The drive circuit 75 drives the recording head 39 at a predetermined timing. Based on the drive control procedure output from the CPU 65, the ASIC 70 generates an output signal. Based on this output signal, the drive circuit 75 controls the drive of the recording head 39. The drive circuit 75 is mounted on the head control board. A signal output from the drive circuit 75 is transmitted from the main board constituting the control unit 64 to the head control board via the flat cable 85. As a result, the recording head 39 selectively ejects each color ink onto the recording paper at a predetermined timing.

  A rotary encoder 76 that detects the rotation amount of the transport roller 60, a linear encoder 77 that detects the position of the carriage 38, and a registration sensor 95 that detects the leading and trailing edges of the recording paper are connected to the ASIC 70. The carriage 38 is moved to one end of the guide rails 43 and 44 when the power of the multifunction machine 10 is turned on, and the detection position by the linear encoder 77 is initialized. When the carriage 38 moves on the guide rails 43 and 44 from the initial position, the optical sensor 35 provided on the carriage 38 detects the pattern of the encoder strip 50. The control unit 64 grasps the moving direction and speed of the carriage 38 based on the number of pulse signals based on the detection of the optical sensor 35. The control unit 64 controls the rotation of the CR motor 73 to control the reciprocation of the carriage 38 based on the moving direction and speed. Further, the control unit 64 grasps the position of the leading or trailing edge of the recording paper based on the signal of the registration sensor 95 and the encoder amount detected by the rotary encoder 76. When the leading edge of the recording sheet reaches a predetermined position of the platen 42, the control unit 64 controls the rotation of the LF motor 71 so as to intermittently convey the recording sheet for each predetermined line feed width. The line feed width is set based on the resolution input as the image recording condition.

  Data is transmitted / received to / from the scanner unit 12, the operation panel 15 for instructing operation of the multifunction device 10, the slot unit 16 into which various small memory cards are inserted, and an external information device such as a personal computer via a parallel cable or a USB cable. A parallel interface 78 and a USB interface 79 are connected to the ASIC 70. Further, an NCU (Network Control Unit) 80 and a modem (MODEM) 81 for realizing the facsimile function are also connected to the ASIC 70.

[Platen 42]
As shown in FIG. 7, the platen 42 has a generally flat plate shape, and the upper surface 109 thereof is disposed to face the lower surface of the recording head 39. The platen 42 is arranged with the width direction of the recording paper (the direction of the arrow 87) as the longitudinal direction. In FIG. 7, the direction of the arrow 89 is the recording paper conveyance direction.

  The platen 42 mainly includes a frame 100, a first fixed support portion 102 and a second fixed support portion 103 provided on the frame 100, and a movable support portion 88 provided slidably on the frame 100. The drive mechanism 105 for slidingly driving the movable support 88 is integrally assembled.

  The frame 100 is made of, for example, a synthetic resin or a steel plate, and constitutes the skeleton of the platen 42. The frame 100 is substantially C-shaped with a cross-sectional shape opened downward. Brackets 106 and 107 are respectively provided integrally with the frame 100 at both ends in the longitudinal direction of the frame 100. The frame 100 is fixed to the frame of the printer unit 11 using brackets 106 and 107. A drive mechanism mounting portion 108 is provided integrally with the frame 100 on one end side in the longitudinal direction of the frame 100 (front side in FIG. 7). The drive mechanism attachment portion 108 has a hook portion 110 that opens in the horizontal direction. The drive mechanism 105 is supported by the hook portion 110.

  A first fixed support portion 102 and a second fixed support portion 103 are provided on the upper surface 109 of the frame 100. A plurality of first fixed support portions 102 are provided in a row at predetermined intervals along the longitudinal direction on the upstream end 94 side in the transport direction on the upper surface 109, and each first fixed support portion 102 is a recording head. It protrudes upward toward 39. A plurality of second fixed support portions 103 are provided in a row at predetermined intervals along the longitudinal direction on the downstream end portion 96 side in the transport direction on the upper surface 109, and each second fixed support portion 103 is a recording head. It protrudes upward toward 39.

  The plurality of first fixed support portions 102 and the plurality of second fixed support portions 103 are separated in the transport direction to form a pair, and the number of first fixed support portions 102 and the number of second fixed support portions 103 are The same. Needless to say, even if the first fixed support portion 102 or the second fixed support portion 103 that is not paired exists on the upper surface 109 of the frame 100, there is no obstacle in implementing the present invention. In the present embodiment, a part of the upper surface 109 recognized as between the first fixed support portion 102 and the second fixed support portion 103 is referred to as a groove 116. The groove 116 extends in the longitudinal direction of the platen 42 on the upper surface 109. The length of the groove 116 in the transport direction (the separation distance between the first fixed support portion 102 and the second fixed support portion 103) corresponds to the nozzle position in the recording head 39, and an ink droplet is ejected from each nozzle. It is wider than the area.

  Each of the first fixed support portions 102 protrudes upward on the upper surface 109 as a thin plate-shaped rib with the conveying direction as a longitudinal direction, and the corner portions of the ribs are chamfered. Similarly, each second fixed support portion 103 protrudes upward on the upper surface 109 as a thin plate-like rib with the conveying direction as the longitudinal direction, and the corner portion is chamfered.

  A plurality of slits 119 extending in the recording sheet conveyance direction are provided on the upper surface 109 of the frame 100. The slits 119 are arranged at predetermined intervals along the longitudinal direction of the platen 42. Each slit 119 extends in the transport direction including between the adjacent first fixed support portions 102 and between the adjacent second fixed support portions 103. Through each slit 119, a movable rib 121 of a movable support portion 88 described later protrudes upward from the upper surface 109 toward the recording head 39.

  As shown in FIGS. 8 and 9, the movable support portion 88 includes a base 120 formed in a box shape and a plurality of movable ribs 121 provided on the base 120. The movable rib 121 is a thin flat plate rib, and protrudes upward from the base 120 with the short direction of the base as the longitudinal direction. The movable rib 121 protrudes from the lower side of the frame 100 of the platen 42 to the upper side of the upper surface 109 of the frame 100 through the slit 119. The movable support part 88 may be comprised from a synthetic resin or a metal. The base 120 is roughly a flat plate shape elongated in the longitudinal direction of the platen 42, but its cross-sectional shape is a C-shape opening downward. The base 120 is fitted into the inside from the lower opening of the frame 100.

  As shown in FIG. 8, slide rollers 93 are provided at both ends of the base 120 in the longitudinal direction. Each slide roller 93 is rotatably supported on the base 120 with the longitudinal direction of the base 120 as an axial direction. In addition, a part of the peripheral surface of each slide roller 93 bulges from the upper surface of the base 120, contacts the inner surface of the frame 100, and rotates following the slide of the movable support portion 88.

  As shown in FIG. 8, a plurality of movable ribs 121 are integrally provided on the upper surface of the base 120. The projecting tip of the movable rib 121 has a mountain shape. The plurality of movable ribs 121 are arranged at predetermined intervals along the longitudinal direction of the base 120, and each movable rib 121 is attached to the frame 100 in the recording sheet conveyance direction (indicated by an arrow 89 in FIG. 8). Direction). The thickness of the movable rib 121 corresponds to the width of the slit 119, and the arrangement of the plurality of movable ribs 121 corresponds to the arrangement of the plurality of slits 119.

  The drive mechanism 105 is for reciprocating the movable support portion 88 in the recording sheet conveyance direction. The drive mechanism 105 transmits the rotation of the paper discharge roller shaft 92 to the movable support portion 88. As shown in FIG. 10, the drive mechanism 105 includes a rotating plate 125 and a lever member 126 (see FIGS. 8 and 9) that converts the rotating motion of the rotating plate 125 into the translational motion of the movable support portion 88. The rotating plate 125 is rotated by the drive transmitted from the paper discharge roller shaft 92 via the power transmission mechanism 124.

  As shown in FIGS. 10 and 11, the rotating plate 125 has a disk shape, and may be made of, for example, resin or metal. The rotating plate 125 includes a circular disk portion 141 and a cylindrical shaft 127 erected at the center of the upper surface of the disk portion 141. The cylindrical shaft 127 is rotatably supported by the frame 100 of the platen 42. Although not shown in the drawing, a support shaft provided on the frame 100 is inserted into and supported by the cylindrical shaft 127. The support shaft extends in a direction perpendicular to the longitudinal direction of the frame 100 and the conveyance direction of the recording paper, that is, in the vertical direction. On the upper surface of the rotating plate 125, guides 128 and 129 that are substantially continuous in the circumferential direction are provided upright. The guides 128 and 129 are both centered on the shaft 127, and the guide 128 is disposed radially outside the guide 129.

  The rotating plate 125 is driven and transmitted from the power transmission mechanism 124 to rotate forward or reverse. Here, the direction of the arrow 130 in FIG. 11 is the forward rotation direction in this specification. The guide 128 is provided with a substantially V-shaped groove 114 and groove 115. The groove 114 forms two wall surfaces in the guide 128. One of the wall surfaces is a forward rotation restricting surface 132 extending in the axial direction of the shaft 127, that is, a direction orthogonal to the rotation direction of the rotating plate 125, and the other wall surface is from the lower edge of the forward rotation restricting surface 132. This is a reverse permissible surface 133 that extends obliquely toward the circumferentially forward rotation side of the guide 128 and continues to the upper surface 137 of the guide 128.

  The groove 115 is disposed at a position that forms an angle of 90 ° (degree) with respect to the groove 114 with the cylindrical shaft 127 as the center. The groove 115 has the same shape as the groove 114, and forms two wall surfaces in the guide 128. One of the wall surfaces is a forward rotation restricting surface 182 that extends in the axial direction of the shaft 127, and the other wall surface extends obliquely from the lower edge of the forward rotation restricting surface 132 toward the circumferentially forward rotation side of the guide 128, and This is a reverse rotation allowable surface 183 that is continuous with the upper surface 137 of the guide 128. As will be described in detail later, the groove 114 determines a first position as an initial position of the rotating plate 125, and the groove 115 determines a second position where the rotating plate 125 is rotated by 90 ° from the initial position.

  The guide 129 is also provided with a substantially V-shaped groove 134. The groove 134 forms two wall surfaces in the guide 129. One of the wall surfaces is a reverse rotation restricting surface 135 extending in the axial direction of the shaft 127, that is, a direction orthogonal to the rotation direction of the rotating plate 125, and the other wall surface is the guide 129 from the lower edge of the reverse rotation restricting surface 135. This is a forward rotation permissible surface 136 that extends obliquely toward the circumferentially reverse side of the guide 129 and continues to the upper surface 138 of the guide 129.

  A lock member 139 and a lock member 140 (see FIG. 12) as the rotation restricting means 156 can be engaged with the groove 114, the groove 115, and the groove 134, respectively. When the lock member 139 is engaged with one of the grooves 114 and 115, the forward rotation of the rotating plate 125 is restricted. When the lock member 140 is engaged with the groove 134, the reverse rotation of the rotating plate 125 is restricted.

  As shown in FIGS. 9 and 12, a guide groove 143 is provided on the back surface 142 of the rotating plate 125. The guide groove 143 is formed so as to draw a locus curve on the cylindrical shaft 127. The shape of the guide groove 143 is described in a polar coordinate system with the center of the cylindrical shaft 127 as the origin. That is, in FIG. 12, when the virtual axis 144 extending in the horizontal direction along the back surface 142 is set, the guide groove 143 is formed along a locus curve that satisfies R = kθ (k is a constant). Here, the angle from the origin toward the left side of the virtual axis 144 is θ = 0, and the clockwise direction around the origin is the positive direction of θ. This trajectory curve depicts an Archimedean spiral. The distance R between the origin and the center of the guide groove 143 and the angle θ are in a linear relationship. However, in this embodiment, the trajectory curve according to R = kθ is in the range of 0 ° ≦ θ ≦ 180 °, and the trajectory curve formed in this range is symmetric about the virtual axis 144 (in FIG. Symmetrical). Therefore, the guide groove 143 is formed along the Archimedean spiral formed symmetrically with respect to the virtual axis 144.

  As shown in FIG. 9, the lever member 126 is a crank-shaped flat plate and connects the base 120 of the movable support portion 88 and the rotating plate 125. Specifically, the distal end portion 145 of the lever member 126 is engaged with the back surface side of the base 120, and the proximal end portion 146 of the lever member 126 is engaged with the guide groove 143 of the rotating plate 125. The intermediate portion 147 of the lever member 126 is supported by the frame 100 of the platen 42, but the support structure between the lever member 126 and the frame 100 of the platen 42 is not shown. An example of the support structure is a structure in which the intermediate portion 147 is rotatably fitted to a support shaft provided on the frame 100. Thereby, the lever member 126 is rotatable around the intermediate portion 147.

  The base end portion 146 of the lever member 126 rotates around the intermediate portion 147 in a state where the base end portion 146 is engaged with the guide groove 143 of the rotating plate 125. The rotation of the lever member 126 is transmitted to the base 120. The base 120 is fitted in the frame 100 and can slide only in the recording paper conveyance direction. Therefore, the rotation of the rotating plate 125 is transmitted to the base 120 via the lever member 126, and the base 120 slides in the recording sheet conveyance direction.

  The displacement amount of the distal end portion 145 of the lever member 126 is a predetermined multiple of the displacement amount of the proximal end portion 146 of the lever member 126. Specifically, this magnification corresponds to the ratio of the distance from the intermediate portion 147 to the distal end portion 145 and the distance from the intermediate portion 147 to the proximal end portion 146. Therefore, the displacement amount of the distal end portion 145 is obtained by amplifying the displacement amount of the proximal end portion 146 by a predetermined factor. Therefore, the rotation amount of the rotating plate 125 is multiplied by a predetermined value by the lever member 126 and converted into the displacement amount of the base 120 in the transport direction. The displacement amount of the base 120 is set as an amount by which the movable rib 121 can reciprocate between the first fixed support portion 102 and the second fixed support portion 103.

  As shown in FIG. 10, the power transmission mechanism 124 includes a torque limiter 148 provided on the paper discharge roller shaft 92 and gears 149 to 151. In the figure, the teeth of the gears 149 to 151 are omitted. The torque limiter 148 includes a flange 153 provided on the paper discharge roller shaft 92, a friction plate 152, a pressing plate 154, and a coil spring 155. The friction plate 152 may typically be a non-woven fabric. The pressing plate 154 is brought into contact with the flange 153 via the friction plate 152. The coil spring 155 elastically biases the pressing plate 154 to the flange 153 together with the friction plate 152. When the pressing plate 154 is pressed against the flange 153 by the coil spring 155, a predetermined frictional force is generated between them. Due to this frictional force, power is transmitted between the pressing plate 154 and the flange 153. When the torque transmitted between the pressing plate 154 and the flange 153 exceeds a certain level, the friction plate 154 slides with respect to the flange 153 and power transmission is not performed. By appropriately setting the elastic force of the coil spring 155, the torque for which power transmission is limited by the torque limiter 148 varies.

  Although omitted in the figure, teeth are formed on the outer peripheral surface of the pressing plate 154, and these teeth mesh with the gear 149. Therefore, when the pressing plate 154 rotates, the gear 149 also rotates. The gear 149 is in mesh with the gear 150, and the gear 150 is in mesh with the gear 151. The rotation center axis of the gear 150 and the rotation center axis of the gear 151 are orthogonal to each other, and the gear 150 and the gear 151 constitute a bevel gear train. As shown in FIG. 10, the outer peripheral surface of the gear 151 is in contact with the outer peripheral surface of the rotating plate 125. In the present embodiment, torque is transmitted between the gear 151 and the rotating plate 125 by the frictional force generated by the contact. Of course, teeth may be formed on both the gear 151 and the rotating plate 125, and both of them may constitute a spur gear train to transmit the drive.

  As shown in FIG. 10, rotation restricting means 156 is provided adjacent to the rotating plate 125. The rotation restricting means 156 includes a lock member 139 and a lock member 140, a coil spring 157, and a contact member 158 that changes the posture of the lock member 139. The coil spring 157 elastically biases the lock member 139 in the direction in which the lock member 139 engages with the rotating plate 125. The contact member 158 is a portion where the carriage 38 contacts to change the posture of the lock member 139.

  The lock member 139 has a crank shape, and a base end side thereof is rotatably supported by a support shaft 159. Therefore, the lock member 139 can rotate in the direction of the arrow 160 about the support shaft 159. An engagement claw 161 is provided at the tip of the lock member 139. The engaging claw 161 has a wedge shape corresponding to the shape of the inner wall surface of the groove 114 in the rotating plate 125 and can be engaged with the groove 114. Since the groove 115 has the same structure as the groove 114, the engagement claw 161 can be engaged with the groove 115.

  The lock member 139 rotates around the support shaft 159, so that the engagement claw 161 is fitted into the groove 114 or 115 and the engagement claw 161 is released from the groove 114 and the groove 115. Change. In this specification, a posture in which the engaging claw 161 is fitted in the groove 114 or 115 is referred to as a “rotation restricting posture”, and a posture in which the engaging claw 161 has escaped from the groove 114 and the groove 115 is a “rotation allowable posture”. It is called. Note that the lock member 139 maintains the rotation-restricted posture at all times when no external force is received by the elastic bias of the coil spring 155.

  When the engaging claw 161 is engaged with the groove 114, the engaging claw 161 comes into contact with the forward rotation restricting surface 132 (see FIG. 11) and the rotating plate 125 is in contact with the rotating plate 125 even if drive transmission in the forward direction is performed. Stop forward rotation. Thereby, the rotating plate 125 is maintained at the first position which is the initial position. Even when the engaging claw 161 engages with the groove 115, the forward rotation of the rotating plate 125 is similarly prevented. Accordingly, the rotating plate 125 is maintained at the second position rotated by 90 ° from the initial position.

  In the case where drive transmission in the reverse rotation direction is transmitted to the rotating plate 125, even if the engagement claw 161 engages with the groove 114 or the groove 115, the engagement claw 161 is applied to the reverse rotation allowable surfaces 133 and 183 (see FIG. 11). The guide reaches the upper surface 137 of the guide 128, and the lock member 139 changes its posture to the rotation allowable posture against the elastic force of the coil spring 155. Thereby, the rotating plate 125 can be reversed regardless of the engagement of the engaging claws 161.

  The locking member 140 has a quadrangular prism shape and does not appear in FIG. 10, but an engagement claw is formed at the lower end portion thereof. This engagement claw is also wedge-shaped like the engagement claw 161 of the lock member 139 and engages with a groove 134 (see FIG. 11) provided in the guide 129 of the rotating plate 125. The lock member 140 can move in the vertical direction and is always elastically biased downward by the coil spring 162. Therefore, when the engaging claw of the lock member 140 engages with the groove 134, the engaging claw comes into contact with the reverse rotation restricting surface 135 (see FIG. 11) and stops the rotation of the rotating plate 125. On the other hand, even if the engaging claw of the lock member 140 is engaged with the groove 134, if the drive transmission in the normal rotation direction is transmitted to the rotating plate 125, the engaging claw is guided to the normal rotation allowable surface 136 (see FIG. 11). Then, it reaches the upper surface of the guide 129 and the lock member 140 moves upward against the elastic force of the coil spring 162. Thereby, the rotating plate 125 can rotate forward regardless of the engagement of the engaging claws of the lock member 140.

  As shown in FIG. 10, the abutting member 158 is provided on the proximal end side of the lock member 139 and can rotate integrally with the lock member 139 about the support shaft 159. The front end 164 of the contact member 158 has a lever shape extending upward, so that the carriage 38 can contact. When the carriage 38 comes into contact with the front end 164 of the contact member 158, the lock member 139 changes its posture to the rotation allowable posture.

[Conveying recording paper for image recording]
The MFP 10 selects a mode of image recording by performing a predetermined operation on the operation panel 15 or by transmitting a predetermined command from an external information device. The image recording mode is so-called margined recording or marginless recording. Hereinafter, conveyance of a recording sheet in image recording when borderless recording is selected will be described.

  When an image recording start command is issued, first, the recording paper loaded on the paper feed tray 20 is fed to the paper transport path 23. Specifically, the control unit 64 drives the LF motor 71 and the paper feed roller 25 is rotated. When feeding paper, the LF motor 71 is driven in reverse. As a result, the transport roller 60 and the paper discharge roller 62 are rotated in the direction opposite to the transport direction, and the paper feed roller 25 is rotated in the direction for feeding the recording paper. The recording paper fed from the paper feed tray 20 to the paper conveyance path 23 is conveyed along the paper conveyance path 23 so as to be reversed from the bottom to the top.

  In the paper transport path 23, the leading edge of the recording paper comes into contact with the registration sensor 95 and the registration sensor 95 is turned on. As the recording sheet is further conveyed, the leading edge of the recording sheet comes into contact with the conveying roller 60 and the pinch roller. Since the conveyance roller 60 is rotated in the direction opposite to the conveyance direction, the leading edge of the recording sheet is not sandwiched between the conveyance roller 60 and the pinch roller in this state, and the recording sheet contacts the conveyance roller 60 and the pinch roller. The resist is processed in the state. The position of the leading edge of the recording paper in the registration process is shown as registration position 174 in FIG. After the recording paper is subjected to the registration process, the control unit 64 drives the LF motor 71 by normal rotation. As a result, the transport roller 60 is rotated in the transport direction, and the registration-processed recording paper is nipped between the transport roller 60 and the pinch roller. Thereafter, the leading edge of the recording sheet passes over the platen 42 as indicated by a line 167 in FIG.

  The sheet discharge roller 62 rotates in the direction opposite to the conveyance direction from the time when the sheet is fed to the registration process. However, as described above, the reverse rotation of the rotating plate 125 is stopped by the lock member 140, so that the torque limiter is stopped. A certain torque or more is generated in 148 to cause slipping, and only the sheet discharge roller 62 rotates in the reverse direction while the rotating plate 125 is stopped. If the rotating plate 125 is not in the initial position when the recording paper is fed, the rotating plate 125 is reversed. However, when the rotating plate 125 is reversed to the initial position, the locking member 140 prevents the rotating plate 125 from being reversed. The Such reverse rotation driving of the LF motor 71 may be set to be performed when the power of the multifunction machine 10 is turned on or after the error is canceled as an operation for initializing the rotary plate 125 to the initial position.

  At the time of borderless recording, the movable support portion 88 is slid following the conveyance of the recording paper. Specifically, when the leading edge of the recording paper reaches the registration position 174, the movable support portion 88 is positioned at the center of the platen 42 (FIG. 14A), and the base end portion 146 of the lever member 126 is the rotating plate. 125 guide grooves 143 are arranged at predetermined positions. The predetermined position of the guide groove 143 is a position indicated by reference numeral 165 in FIG. In other words, the predetermined position indicated by reference numeral 165 is a position where a virtual axis 172 passing through the center of the cylindrical shaft 127 and orthogonal to the virtual axis 144 intersects the guide groove 143. 14A is the initial position of each member corresponding to the initial position of the rotating plate 125. The relative positional relationship among the movable support portion 88, the rotating plate 125, and the lever member 126 in FIG.

  When the leading edge of the recording sheet reaches the platen 42 after the registration process, the LF motor 71 is intermittently driven in the forward direction as indicated by a diagram 168 in FIG. Further, the CR motor 73 is driven at a predetermined timing before and after the leading edge of the recording paper reaches the platen 42 so that the carriage 38 contacts the contact member 158. The timing at which the contact member 158 changes its posture due to the contact of the carriage 38 is shown by the diagrams 169, 175, 176, and 177. In the diagram 169 and the like, the posture change of the contact member 158 such that the engagement claw 161 of the lock member 139 retracts from the groove 114 or 115 is ON.

  When the contact member 158 is turned ON, the engagement between the engagement claw 161 of the lock member 139 and the groove 114 is released, and the rotating plate 125 can be rotated forward. Therefore, after the registration processing, when the discharge roller shaft 92 is rotated in the transport direction by the LF motor 71, this rotation is transmitted to the rotating plate 125 via the power transmission mechanism 124, and the rotating plate 125 rotates in the normal direction. Then, the rotation of the rotating plate 125 is transmitted to the movable support portion 88 by the lever member 126, and the movable rib 121 of the movable support portion 88 is displaced as shown by a line 170 in FIG.

  When the rotating plate 125 rotates forward by 90 °, the engaging claw 161 engages with the groove 115. As a result, the rotating plate 125 is further prevented from rotating forward from that position. When the rotating plate 125 rotates forward, the base end portion 146 of the lever member 126 relatively moves in the direction of the arrow 171 from the predetermined position 165 in FIG. Since the distance between the predetermined position 165 of the base end portion 146 and the cylindrical shaft 127 gradually decreases with the rotation of the rotating plate 125, the lever member 126 swings about the intermediate portion 147 as a swing center. The movable support portion 88 moves to the upstream side in the transport direction. When the rotation angle of the rotating plate 125 reaches 90 ° and the forward rotation is stopped, the movable support portion 88 is at the upstream end in the transport direction (FIG. 14B). The movable support portion 88 moves to the upstream end described above and stops before the leading edge of the recording paper passes through the first fixed support portion 102. At this time, the movable rib 121 of the movable support portion 88 is substantially at the same position as the first fixed support portion 102 in the transport direction (FIG. 15A).

  As shown in FIG. 15, when the leading edge of the recording paper 184 reaches the platen 42 and is further conveyed, the recording paper 184 is supported by the first fixed support portion 102 and the movable rib 121. In other words, the recording paper 184 covers the first fixed support portion 102 and the movable rib 121 from above (FIG. 15B). Thereafter, the CR motor 73 is driven at a predetermined timing, and the carriage 38 comes into contact with the contact member 158 at the timing shown in the diagram 175. As a result, similarly to the above, the lock member 139 is turned ON, the engagement between the engagement claw 161 and the groove 115 is released, and the rotating plate 125 can be rotated forward again. As a result, by the intermittent drive of the LF motor 71, the movable rib 121 is displaced downstream in the transport direction as shown in a diagram 170. Since the recording paper 184 is also transported by the transport roller 60 that is rotated by intermittent driving of the LF motor 71, the recording paper 184 is transported on the platen 42 while being supported by the movable rib 121 as shown in a diagram 167. The relative positional relationship among the movable support portion 88, the rotating plate 125, and the lever member 126 changes in the order of FIGS.

  In a range in which the rotation angle of the rotating plate 125 exceeds 90 ° and reaches 270 °, the distance between the position 165 of the base end portion 146 and the cylindrical shaft 127 gradually increases as the rotating plate 125 rotates. Accordingly, as shown in FIGS. 14B to 14D, the lever member 126 swings around the intermediate portion 147 as the swing center, and as a result, the movable support portion 88 moves downstream in the transport direction. To do. When the rotation angle of the rotating plate 125 reaches 270 °, the movable rib 121 is located at substantially the same position as the second fixed support portion 103 in the transport direction. Furthermore, as the rotating plate 125 rotates, the distance between the position 165 of the base end portion 146 and the cylindrical shaft 127 gradually decreases as the rotating plate 125 rotates. Therefore, the lever member 126 swings around the intermediate portion 147 as the swing center, and the movable support portion 88 moves upstream in the transport direction. When the rotation angle of the rotating plate 125 reaches 360 °, the movable support portion 88 returns to a position corresponding to the initial position of the rotating plate 125.

  While the recording paper 184 is intermittently conveyed, ink droplets of each color are selectively ejected from the recording head 39 that slides with the carriage 38 and land on the recording paper 184. In borderless recording, ink droplets are ejected to the peripheral edge of the recording paper 184. Even if there are ink droplets that do not land on the recording paper 184, ink droplets are applied to the movable rib 121 covered by the recording paper 184. Never land.

  When the rotating plate 125 returns to the initial position, the forward rotation of the rotating plate 125 is stopped by the engagement claw 161 engaging with the groove 114 as described above. On the other hand, the driving force of the LF motor 71 is transmitted to the transport roller 60 and the paper discharge roller shaft 92, and the recording paper 184 is transported intermittently. Then, as shown in the diagram 173, the rear end of the recording paper 184 reaches the platen 42. The position of the trailing edge of the recording paper 184 is determined based on the detection signal of the registration sensor 95. Then, the carriage 38 is brought into contact with the contact member 158 at a predetermined timing, and the contact member 158 is turned on as shown in a diagram 176. As a result, as described above, the engagement between the engagement claw 161 of the lock member 139 and the groove 114 is released, and the rotating plate 125 can be rotated forward.

  By the normal rotation of the rotating plate 125, the movable rib 121 is displaced as shown in a diagram 170. The relative positional relationship among the movable support portion 88, the rotating plate 125, and the lever member 126 changes again in the order of FIGS. When the movable rib 121 moves to the upstream end in the conveying direction, the forward rotation of the rotating plate 125 is stopped by the engagement between the engagement claw 161 and the groove 115, and the movable rib 121 stops at the upstream end. Then, before the rear end of the recording paper 184 passes through the first fixed support portion 102, the carriage 38 contacts the contact member 158 at the timing shown in the diagram 177. As a result, the engagement between the engagement claw 161 and the groove 115 is released, and the rotating plate 125 rotates forward. As a result, the movable rib 121 is displaced as shown by the diagram 170. At that time, the recording paper 184 is conveyed while being supported by the movable rib 121. The relative positional relationship among the movable support portion 88, the rotating plate 125, and the lever member 126 changes in the order of FIGS.

  While the recording paper 184 is intermittently conveyed, ink droplets of each color are selectively ejected from the recording head 39 that slides with the carriage 38 and land on the recording paper 184. In borderless recording, ink droplets are ejected to the peripheral edge of the recording paper 184. Even if there are ink droplets that do not land on the recording paper 184, ink droplets are applied to the movable rib 121 covered by the recording paper 184. Never land. When the rotating plate 125 rotates once, the rotating plate 125 returns to the initial position. When the image recording is completed, the LF motor 71 is continuously driven in the normal rotation, and the recording paper 184 is discharged to the paper discharge tray 21.

  Although not described in detail here, the printer unit 11 can also perform bordered recording. In margined recording, the movable support portion 88 does not need to move following the recording paper 184, so the carriage 38 is not in contact with the contact member 158, and the rotating plate 125 remains at the initial position. It is. Since the movable support portion 88 is always disposed at the center of the platen 42, the leading end or the rear end of the recording paper 184 does not hang down between the first fixed support portion 102 and the second fixed support portion 103, and recording is performed. The distance (head gap) between the head 39 and the recording paper 184 is kept constant.

[Cleaning method of platen 42]
The multifunction device 10 can select a cleaning mode by performing a predetermined operation on the operation panel 15 or by transmitting a predetermined command from an external information device. When the cleaning mode is executed, the cleaning method according to the present invention is performed. As described above, a part of the ink ejected from the recording head 39 floats as ink mist and adheres to the upper surface 109 of the platen 42. The ink mist adhering to the upper surface 109 of the platen 42 can grow into large ink droplets. This ink droplet causes the recording paper to become dirty as residual ink. Cleaning is performed to remove such residual ink. The timing at which cleaning is performed is arbitrary. For example, a user who finds that the recording paper is soiled by residual ink may be arbitrarily performed, or a warning is displayed so that cleaning is performed after a predetermined amount of image recording has been performed. As such, it may be set in advance.

  Each operation in cleaning is stored in the ROM 66 as a predetermined program, and the control unit 64 operates the printer unit 11 based on the program. Prior to the cleaning, a cleaning sheet 197 (see FIG. 17) is placed on the paper feed tray 20. Is loaded. The cleaning sheet 197 is the same sheet as the recording paper, and can absorb and hold ink droplets. Although the cleaning sheet 197 corresponds to the sheet in the present invention, the cleaning sheet 197 does not need to be prepared as a dedicated product, and plain paper used for image recording may be used as the sheet in the present invention.

The cleaning method described in detail below mainly includes steps S1 to S5 described below. In the present invention, the steps indicated as S1, S4, and S5 below can be omitted, and a cleaning mode in which these steps are omitted may be set in the printer unit 11.
(S1) A step of bending the cleaning sheet 197 (corresponding to the fifth step of the present invention).
(S2) A step in which the movable support portion 88 is moved to the first fixed support portion 102 side or the second fixed support portion 103 side (corresponding to the first step of the present invention).
(S3) A step in which the front end or the rear end of the cleaning sheet 197 is brought into contact with the upper surface 109 between the first fixed support portion 102 and the second fixed support portion 103 (corresponding to the second step of the present invention).
(S4) A step of reciprocating the cleaning sheet 197 in a state where the front end or the rear end of the cleaning sheet 197 is in contact with the upper surface 109 (corresponding to the third step of the present invention).
(S5) Corresponds to a step (fourth step of the present invention) in which the front or rear end of the cleaning sheet 197 is separated from the upper surface 109 and dried.

  When there is a cleaning start command, first, the cleaning sheet 197 loaded in the paper feed tray 20 is fed to the paper transport path 23. Specifically, the control unit 64 drives the LF motor 71 and the paper feed roller 25 is rotated. At this time, the LF motor 71 is driven in reverse. As a result, the transport roller 60 and the paper discharge roller 62 are rotated in the direction opposite to the transport direction, and the paper feed roller 25 is rotated in the direction in which the cleaning sheet 197 is fed. The cleaning sheet 197 fed from the paper feed tray 20 to the paper conveyance path 23 is conveyed along the paper conveyance path 23 so as to be reversed from the bottom to the top.

  When the leading edge of the cleaning sheet 197 reaches the curved portion 17 of the paper conveyance path 23, conveyance of the cleaning sheet 197 is temporarily stopped. Specifically, the control unit 64 stops driving the LF motor 71 and counts the stop time. When the stop time reaches a preset time, the driving of the LF motor 71 is resumed. As a result, the front end portion of the cleaning sheet 197 is left for the stop time while being curved along the curved portion 17. In the bending portion 17, the surface of the cleaning sheet 197 that faces the recording head 39 is on the outer side, and therefore, by this temporary stop, the distal end portion of the cleaning sheet 197 is bent and deformed to contact with the upper surface 109 of the platen 42 ( S1). Note that the stop time in the temporary stop can be preset in the ROM 66 as a time during which the cleaning sheet 197 can be bent and deformed.

  When the cleaning sheet 197 is conveyed again, the leading edge of the cleaning sheet 197 contacts the registration sensor 95 and the registration sensor 95 is turned on. When the cleaning sheet 197 is further conveyed, the leading end side of the cleaning sheet 197 is nipped between the conveying roller 60 and the pinch roller and conveyed. In the cleaning, the above-described registration process is optional, but the control unit 64 temporarily stops driving the LF motor 71 in order to switch the rotation of the LF motor 71 from the reverse rotation direction to the normal rotation direction (FIG. 16 at 188). When the LF motor 71 is driven in the forward direction, the conveyance roller 60 is rotated in the conveyance direction, and the cleaning sheet 197 is nipped between the conveyance roller 60 and the pinch roller and conveyed on the platen 42. The front end of the cleaning sheet 197 conveyed on the platen 42 is shown by a line 187 in FIG.

  Note that the paper discharge roller 62 rotates in the direction opposite to the conveyance direction from the time when the paper is fed to the registration process. However, as described above, the reverse rotation of the rotary plate 125 is stopped by the lock member 140. Torque exceeding the limit is generated in the torque limiter 148 and slipping occurs, and only the paper discharge roller 62 rotates in the reverse direction while the rotating plate 125 is stopped.

  During cleaning, the movable support portion 88 is slid at a predetermined timing with respect to the conveyance of the cleaning sheet 197. In detail, the CR motor 73 is driven and the carriage 38 comes into contact with the contact member 158 before the leading end of the cleaning sheet 197 reaches the position 188 where it comes into contact with the transport roller 60. A timing at which the posture of the contact member 158 changes due to the contact of the carriage 38 is shown by a line 189. In the diagram 189, the posture change of the contact member 158 such that the engagement claw 161 of the lock member 139 is retracted from the groove 114 or 115 is ON.

  When the contact member 158 is turned ON, the engagement between the engagement claw 161 of the lock member 139 and the groove 114 is released, and the rotating plate 125 can be rotated forward. Therefore, when the discharge roller shaft 92 is rotated in the transport direction by the LF motor 71, this rotation is transmitted to the rotating plate 125 via the power transmission mechanism 124, and the rotating plate 125 rotates in the forward direction. Then, the rotation of the rotating plate 125 is transmitted to the movable support portion 88 by the lever member 126, and the movable rib 121 of the movable support portion 88 is displaced as shown by a diagram 190 in FIG.

  When the rotating plate 125 rotates forward by 90 °, the engaging claw 161 engages with the groove 115. As a result, the rotating plate 125 is further prevented from rotating forward from that position. In addition, since the engagement between the locking claw 161 and the groove 115 does not prevent the rotation of the rotating plate 125, the rotating plate 125 can be reversed from that position. When the rotating plate 125 rotates forward from the initial position, the base end portion 146 of the lever member 126 relatively moves in the direction of the arrow 171 from the predetermined position 165 in FIG. Since the distance between the predetermined position 165 of the base end portion 146 and the cylindrical shaft 127 gradually decreases with the rotation of the rotating plate 125, the lever member 126 swings about the intermediate portion 147 as a swing center. The movable support portion 88 moves to the upstream side in the transport direction. When the rotation angle of the rotating plate 125 reaches 90 ° and the forward rotation is stopped, the movable support portion 88 is at the upstream end in the transport direction (FIG. 14B). At this time, the movable rib 121 of the movable support portion 88 is substantially at the same position as the first fixed support portion 102 in the transport direction (S2).

  When the leading end of the cleaning sheet 197 reaches the platen 42, the cleaning sheet 197 is supported by the first fixed support portion 102 and the movable rib 121. When the cleaning sheet 197 is further conveyed, the leading end portion of the cleaning sheet 197 advances to the second fixed support portion 103 beyond the first fixed support portion 102 and the movable rib 121. At this time, the movable rib 121 remains restrained on the upstream side in the transport direction. In other words, there is no movable rib 121 between the first fixed support portion 102 and the second fixed support portion 103. Then, the cleaning sheet 197 is bent and hangs downward before the tip of the cleaning sheet 197 reaches the second fixed support portion 103. Further, as described above, the tip portion of the cleaning sheet 197 is curved and deformed to the side in contact with the upper surface 109. Accordingly, as shown in FIG. 17A, the tip of the cleaning sheet 197 contacts the upper surface 109 of the platen 42 before reaching the second fixed support portion 103 (S3).

  Since the cleaning sheet 197 can absorb ink, the ink droplet 198 adhering to the upper surface 109 is absorbed by the cleaning sheet 197 when the tip of the cleaning sheet 197 contacts the upper surface 109 of the platen 42.

  The control unit 64 drives the LF motor 71 alternately in the forward direction and the reverse direction at predetermined time intervals immediately before the leading edge of the cleaning sheet 197 reaches the second fixed support unit 103 (FIG. 16). Diagram 191). As a result, the transport roller 60 rotates alternately in the transport direction and the opposite direction, and the cleaning sheet 197 repeats forward and backward with respect to the transport direction. Thereby, the tip of the cleaning sheet 197 slides with respect to the upper surface 109 (S4). Note that the number of times of driving the LF motor 71 by switching the rotation direction is set to three in this embodiment, but this number may be arbitrarily changed. Further, the time for driving in the forward rotation direction or the reverse rotation direction is set in consideration of the range in which the tip of the cleaning sheet 197 slides.

  On the other hand, as described above, the rotation plate 125 is prevented from rotating in the forward rotation direction and allowed to rotate in the reverse rotation direction by the engagement of the engagement claw 161 and the groove 115. 121 repeats forward and backward in the transport direction in the vicinity of the first fixed support portion 102, but the movement of the movable rib 121 does not separate the tip of the cleaning sheet 197 from the upper surface 109. As a result, the ink droplets 198 adhering to the upper surface 109 of the platen 42 are removed within a range where the tip of the cleaning sheet 197 slides.

  Subsequently, the movable rib 121 is returned toward the initial position, and the cleaning sheet 197 is retracted in the direction opposite to the conveying direction. Specifically, the control unit 64 drives the LF motor 71 in the reverse direction. As a result, the rotating plate 125 reverses from the position rotated 90 ° to the initial position as described above. In response, the movable rib 121 is slid from the vicinity of the first fixed support portion 102 to the vicinity of the center between the first fixed support portion 102 and the second fixed support portion 103, that is, toward the initial position. At this time, the front end of the cleaning sheet 197 that has been hung downward is supported by the movable rib 121, and the front end of the cleaning sheet 197 is separated from the upper surface 109 of the platen 42. Then, the control unit 64 stops driving the LF motor 71 in a state where the tip of the cleaning sheet 197 is on the downstream side in the transport direction from the movable rib 102, that is, in a state where the cleaning sheet 197 covers the movable rib 121. As a result, as shown in FIG. 17B, the leading end of the cleaning sheet 197 that has absorbed ink is separated from the upper surface 109 of the platen 42 and is not in contact with the movable rib 121. In this state, the LF motor 71 is stopped for a preset drying time, whereby the leading end of the cleaning sheet 197 that has absorbed ink is dried (S5). This drying time can be preset and stored in the ROM 66 in consideration of the material of the cleaning sheet 197 and the amount of ink absorbed.

  After a predetermined drying time has elapsed, the movable rib 121 is returned to the initial position. Specifically, the control unit 64 drives the LF motor 71 in the reverse direction. As a result, the rotating plate 125 is reversely rotated to return to the initial position, the engaging claw 161 of the lock member 139 engages with the groove 114, and the normal rotation of the rotating plate 125 is stopped, and the engaging claw of the lock member 140 Engages with the groove 134 to stop the reverse rotation of the rotating plate 125. On the other hand, the driving force of the LF motor 71 is transmitted to the conveyance roller 60, and the cleaning sheet 197 is conveyed in the direction opposite to the conveyance direction. At this time, the tip of the cleaning sheet 197 slides on the upper end of the movable rib 121, but since the tip is already dried, the ink does not adhere to the movable rib 121. After the movable rib 121 returns to the initial position, the control unit 121 continuously drives the LF motor 71 in the forward rotation direction. As a result, the tip of the cleaning sheet 197 passes over the platen 42 as shown in the diagram 188.

  When the rear end of the cleaning sheet 197 reaches the curved portion 17 of the sheet conveyance path 23, conveyance of the cleaning sheet 197 is temporarily stopped. Specifically, the control unit 64 stops driving the LF motor 71 and counts the stop time. When the stop time reaches a preset time, the driving of the LF motor 71 is resumed. As a result, the rear end portion of the cleaning sheet 197 is left for the stop time while being curved along the curved portion 17. As a result, the rear end portion of the cleaning sheet 197 is bent and deformed to the side in contact with the upper surface 109 of the platen 42 in the same manner as the front end portion (S1).

  When the cleaning sheet 197 is conveyed again, the rear end of the cleaning sheet 197 passes through the registration sensor 95 and the registration sensor 95 is turned OFF. After a predetermined time has elapsed, the rear end of the cleaning sheet 197 is conveyed on the platen 42. The The rear end of the cleaning sheet 197 conveyed on the platen 42 is shown by a diagram 192 in FIG. Note that after the rear end of the cleaning sheet 197 passes through the conveyance roller 60 and the pinch roller, the cleaning sheet 197 is nipped and conveyed by the paper discharge roller 62 and the spur 63.

  Again, the movable support 88 is slid at a predetermined timing with respect to the conveyance of the cleaning sheet 197. In detail, before the rear end of the cleaning sheet 197 reaches the platen 42, the CR motor 73 is driven to bring the carriage 38 into contact with the contact member 158. This timing at which the posture of the contact member 158 changes due to the contact of the carriage 38 is shown by a line 193. As a result, similarly to the above, the rotating plate 125 can rotate forward, and the movable rib 121 is displaced as shown by a diagram 195 in FIG.

  When the rotating plate 125 rotates forward by 90 °, the engaging claw 161 engages with the groove 115. As a result, the rotating plate 125 is further prevented from rotating forward from that position, and the movable rib 121 is in a position equivalent to the first fixed support portion 102. Thereafter, the CR motor 73 is driven again and the carriage 38 comes into contact with the contact member 158. This timing is illustrated by diagram 194. Thereby, the rotating plate 125 can further rotate forward, and the movable rib 121 slides from the first fixed support portion 102 toward the second fixed support portion 103. When the rotation angle of the rotating plate 125 exceeds 90 ° and reaches 270 °, as shown in FIGS. 14B to 14D, the lever member 126 swings around the intermediate portion 147 as the swing center. As a result, the movable rib 121 is substantially at the same position as the second fixed support portion 103 in the transport direction.

  At this time, the rear end of the cleaning sheet 197 advances to the second fixed support portion 103 beyond the first fixed support portion 102, but a movable rib is provided between the first fixed support portion 102 and the second fixed support portion 103. 121 does not exist. Then, before the rear end of the cleaning sheet 197 reaches the second fixed support portion 103, the cleaning sheet 197 is bent and hangs downward. Further, as described above, the rear end portion of the cleaning sheet 197 is curved and deformed to the side in contact with the upper surface 109. Thus, as shown in FIG. 18A, the rear end of the cleaning sheet 197 contacts the upper surface 109 of the platen 42 before reaching the second fixed support portion 103 (S3).

  Since the cleaning sheet 197 can absorb ink, the ink droplet 199 adhering to the upper surface 109 is absorbed by the cleaning sheet 197 when the rear end of the cleaning sheet 197 contacts the upper surface 109 of the platen 42.

  The control unit 64 drives the LF motor 71 alternately in the forward direction and the reverse direction at predetermined time intervals at a timing immediately after the rear end of the cleaning sheet 197 passes through the first fixed support unit 102 (see FIG. 16 196). As a result, the paper discharge roller 61 rotates alternately in the transport direction and the opposite direction, and the cleaning sheet 197 repeats forward and backward in the transport direction. Thereby, the rear end of the cleaning sheet 197 slides with respect to the upper surface 109 (S4). Note that the number of times of driving the LF motor 71 by switching the rotation direction is set to three in this embodiment, but this number may be arbitrarily changed. Further, the time for driving in the forward rotation direction or the reverse rotation direction is set in consideration of the range in which the rear end of the cleaning sheet 197 slides.

  On the other hand, since the rotation plate 125 is not restricted from rotating in either the forward direction or the reverse direction, the movable rib 121 repeats forward and backward in the transport direction in the vicinity of the second fixed support portion 103. The movement of 121 does not separate the rear end of the cleaning sheet 197 from the upper surface 109. As a result, the ink droplets 199 adhering to the upper surface 109 of the platen 42 are removed within a range in which the rear end of the cleaning sheet 197 slides.

  Subsequently, the movable rib 121 is returned to the initial position, and the cleaning sheet 197 is conveyed in the conveyance direction. Specifically, the control unit 64 drives the LF motor 71 in the normal rotation direction. As a result, the rotating plate 125 further rotates forward from the position rotated by 270 ° as described above. In response, the movable rib 121 is slid from the vicinity of the second fixed support portion 103 to the vicinity of the center between the first fixed support portion 102 and the second fixed support portion 103, that is, toward the initial position. At this time, the rear end of the cleaning sheet 197 hanging downward is supported by the movable rib 121, and the rear end of the cleaning sheet 197 is separated from the upper surface 109 of the platen 42. Then, the control unit 64 stops driving the LF motor 71 in a state where the rear end of the cleaning sheet 197 is upstream of the movable rib 102 in the transport direction, that is, in a state where the cleaning sheet 197 covers the movable rib 121. As a result, as shown in FIG. 18B, the rear end of the cleaning sheet 197 that has absorbed ink is separated from the upper surface 109 of the platen 42 and is not in contact with the movable rib 121. In this state, the LF motor 71 is stopped for a preset drying time, whereby the rear end of the cleaning sheet 197 that has absorbed ink is dried (S5). This drying time can be preset and stored in the ROM 66 in consideration of the material of the cleaning sheet 197 and the amount of ink absorbed.

  After a predetermined drying time has elapsed, the movable rib 121 is returned to the initial position. Specifically, the control unit 64 drives the LF motor 71 in the forward rotation direction. As a result, the rotating plate 125 is rotated forward and returned to the initial position, the engaging claw 161 engages with the groove 114, the normal rotation of the rotating plate 125 is stopped, and the engaging claw of the lock member 140 is moved into the groove 134. And the reverse rotation of the rotating plate 125 is stopped. On the other hand, the driving force of the LF motor 71 is transmitted to the paper discharge roller 61, and the cleaning sheet 197 is transported in the transport direction. At this time, the rear end of the cleaning sheet 197 slides over the upper end of the movable rib 121, but the rear end is already dried, so that ink does not adhere to the movable rib 121. Further, when the LF motor 71 is continuously driven in the forward rotation direction, the rear end of the cleaning sheet 197 passes over the platen 42 as shown in the diagram 192, and the paper discharge roller 61 and the spur 62 are driven. However, the rear end of the cleaning sheet 197 is already dried, so that ink does not adhere to the discharge roller 61 or the spur 62.

[Effects of this embodiment]
According to the present embodiment, the movable rib 121 moves to the upstream side or the downstream side in the transport direction, and the cleaning sheet 197 supported only on one of the first fixed support portion 102 and the second fixed support portion 103. Since the front end or the rear end hangs down between the first fixed support portion 102 and the second fixed support portion 103 and comes into contact with the upper surface 109 of the platen 42, the ink droplets 198 and 199 remaining on the upper surface 109 of the platen 42 are removed. The cleaning sheet 197 absorbs and removes it. Thereby, the upper surface 109 of the platen 42 can be cleaned.

  In the cleaning described above, the control unit 64 reciprocates the cleaning sheet 197 in the transport direction in a state where the front end or the rear end of the cleaning sheet 197 is in contact with the upper surface 109 via the transport mechanism. The front end or the rear end of the platen slides on the upper surface 109 of the platen 42. Thereby, the ink droplets 198 and 199 in the range in which the cleaning sheet 197 slides are absorbed and removed.

  In the cleaning described above, the control unit 64 moves the movable rib 121 to the vicinity of the center between the first fixed support unit 102 and the second fixed support unit 103 via the drive mechanism and the transport mechanism. The front or rear end of the cleaning sheet 197 is separated from the upper surface 109 of the platen 42, and then the movable rib 121 is waited for a predetermined drying time and the conveyance of the cleaning sheet 197 is stopped, thereby cleaning the ink that has absorbed the ink. Since the leading end portion or the trailing end portion of the sheet 197 is dried, even if the cleaning sheet 197 is subsequently conveyed, the ink does not adhere to the movable rib 121, the paper discharge roller 61, and the like.

  In the above-described cleaning, the control unit 64 temporarily stops the conveyance of the cleaning sheet 197 in the curved portion 17 in the conveyance path 23 via the conveyance mechanism, so that the leading end or the rear end of the cleaning sheet 197 is moved to the platen 42. Since the bending deformation is performed in the bending direction in contact with the upper surface 109, there is an advantage that the cleaning sheet 197 is likely to hang between the first fixed support portion 102 and the second fixed support portion 103.

[Modification]
In addition, this invention may be implemented by the modification shown below.

  In the cleaning described above, the control unit 64 may perform pin check or test printing by ejecting ink from the recording head 39 to the cleaning sheet 197. In the above-described embodiment, the period from when the leading end of the cleaning sheet 197 contacts the upper surface 109 of the platen 42 and a predetermined drying time elapses until the rear end of the cleaning sheet 197 contacts the upper surface 109 of the platen 42. In FIG. 16, the control unit 64 continuously drives the LF motor 71 in the forward rotation direction, and the cleaning sheet 197 is continuously conveyed by the conveyance roller 60 and the paper discharge roller 61. However, as shown in FIG. When returned to the initial position, the cleaning sheet 197 is supported by the first fixed support portion 102, the second fixed support portion 103, and the movable rib 121, and a head gap with respect to the cleaning sheet 197 (from the recording head 39 to the cleaning sheet). The distance to 197) is kept constant.

  Accordingly, by performing pin check or test printing of the recording head 39 during the above-described period, the areas other than the upper end and the lower end of the cleaning sheet 197 can be effectively used. Further, since the cleaning of the platen 42 and pin check or test printing can be performed simultaneously, the time required for maintenance is reduced. Note that only one or both of the pin check and the test print may be performed on one cleaning sheet 197. In addition, a known timing can be adopted as the timing of ink ejection from each pin (nozzle) of the recording head 39 in the pin chuck or test printing.

  In this embodiment, the forward rotation of the rotating plate 125 is stopped at a position rotated by 90 ° from the initial position. However, the rotational position for stopping the forward rotation or reverse rotation of the rotating plate 125 is not limited to the present invention. It may be changed without changing the gist of the above. For example, if the forward rotation and the reverse rotation of the rotating plate 125 are stopped at two positions rotated by 90 ° and 270 ° from the initial position, the movable rib 121 is located near the first fixed support portion 102 and the second fixed support portion 103. Once stopped at two nearby positions, the carriage 38 does not slide unless the contact member 158 changes its posture. Then, when the LF motor 71 is rotated alternately in the forward rotation direction and the reverse rotation direction and the front end or the rear end of the cleaning sheet 197 slides on the upper surface 109 of the platen 42, the movable rib 121 may slide in conjunction with it. Absent.

  On the other hand, if the rotation of the rotating plate 125 is not restricted except at the initial position, the LF motor 71 is rotated alternately in the forward rotation direction and the reverse rotation direction so that the front end or the rear end of the cleaning sheet 197 moves the upper surface 109 of the platen 42. When sliding, the movable rib 121 slides in conjunction with each other. However, in this embodiment, the movable rib 121 has a predetermined timing like the timing when the rear end of the cleaning sheet 197 slides on the upper surface 109 of the platen 42. A timing and a sliding range may be set so that the front end or the rear end of the cleaning sheet 197 is not separated from the upper surface 109 even if the cleaning sheet slides within the range.

FIG. 1 is an external perspective view of a multifunction machine 10 according to an embodiment of the present invention. FIG. 2 is a longitudinal sectional view showing the internal configuration of the multifunction machine 10. FIG. 3 is a partially enlarged cross-sectional view showing the main configuration of the printer unit 11. FIG. 4 is a plan view showing the main part of the printer unit 11. FIG. 5 is a perspective view showing the main part of the printer unit 11. FIG. 6 is a block diagram illustrating a configuration of the control unit 64 of the multifunction machine 10. FIG. 7 is an enlarged perspective view of the platen 42 and the drive mechanism 105. FIG. 8 is an enlarged perspective view of the movable support portion 88. FIG. 9 is an enlarged perspective view of the movable support portion 88 viewed from the bottom surface side of the platen 42. FIG. 10 is an enlarged perspective view of the drive mechanism 105. FIG. 11 is an enlarged perspective view of the rotating plate 125. FIG. 12 is a bottom view of the rotating plate 125. FIG. 13 is a timing chart showing the timing of conveying the recording paper and sliding the movable support portion 88 when borderless recording is performed. FIG. 14 is a diagram illustrating the displacement of the movable support portion 88 during the conveyance of the recording paper in the order of (a) to (d). FIG. 15 is a diagram showing a positional relationship between the recording sheet and the movable rib 121 in borderless recording. FIG. 16 is a timing chart showing the timing of conveying the cleaning sheet 197 and sliding the movable rib 121 when cleaning is performed. FIG. 17 is a diagram illustrating a positional relationship between the cleaning sheet 197 and the movable rib 121 in cleaning. FIG. 18 is a diagram illustrating a positional relationship between the cleaning sheet 197 and the movable rib 121 in cleaning.

Explanation of symbols

11: Printer unit (inkjet recording apparatus)
17... Curved portion 23... Paper transport path 26.
39 ... Recording head 42 ... Platen 60 ... Conveying roller (conveying mechanism)
61: Paper discharge roller (conveyance mechanism)
62 ... spur (conveyance mechanism)
102 ... 1st fixed support part (fixed support part)
103 ... second fixed support part 105 ... drive mechanism 109 ... 121 protruding from the upper surface ... movable rib (movable support part)
197 ... Cleaning sheet (sheet)

Claims (11)

A pair of fixed support portions protruding from the upper surface are provided spaced apart in the sheet conveyance direction, and a movable support portion protruding from the upper surface and reciprocating between the pair of fixed support portions in the conveyance direction is provided. In the platen, a first step in which the movable support portion moves upstream or downstream in the transport direction;
A sheet that can absorb ink is fed to the platen, and the leading edge or the trailing edge of the sheet is suspended between the pair of fixed support portions, whereby the leading edge or the trailing edge of the sheet comes into contact with the top surface. And a step of cleaning the platen for an ink jet recording apparatus.   In a state where the leading edge or the trailing edge of the sheet is in contact with the upper surface, the sheet further includes a third step in which the leading edge or the trailing edge of the sheet slides with respect to the upper surface by reciprocating the sheet in the transport direction. The method for cleaning a platen for an inkjet recording apparatus according to claim 1.   The movable support portion is moved to the vicinity of the center between the pair of fixed support portions to separate the front end or the rear end of the sheet from the upper surface, and then the movable support portion waits for a predetermined drying time and The method for cleaning a platen for an ink jet recording apparatus according to claim 1, further comprising a fourth step of stopping conveyance of the sheet.   The ink jet recording according to any one of claims 1 to 3, further comprising a fifth step of bending and deforming a leading end or a trailing end of the sheet in a bending direction in contact with the upper surface before feeding the sheet to the platen. A method for cleaning an apparatus platen.   5. The inkjet recording apparatus according to claim 4, wherein, in the fifth step, the sheet is conveyed to a curved conveyance path that communicates with the platen, and the sheet is curved and deformed by temporarily stopping conveyance of the sheet in the conveyance path. Cleaning method for platen.   6. The cleaning of the platen for an ink jet recording apparatus according to claim 1, further comprising a sixth step of ejecting ink droplets from the recording head to the sheet and performing pin check or test printing of the recording head. Method. A recording head that selectively ejects ink droplets;
A platen whose upper surface is disposed opposite to the recording head;
A pair of fixed support portions projecting from the platen toward the recording head and separated in the sheet conveyance direction;
A movable support portion that protrudes from the platen toward the recording head and reciprocates between the pair of fixed support portions in the transport direction;
A transport mechanism for transporting a sheet to the platen;
When a sheet capable of absorbing ink by the transport mechanism is fed to the platen, the leading edge or the trailing edge of the sheet hangs between the pair of fixed support portions and comes into contact with the upper surface of the platen. An ink jet recording apparatus comprising: a drive mechanism configured to move the movable support portion upstream or downstream in the transport direction.   The ink jet recording apparatus according to claim 7, wherein the driving mechanism reciprocates the sheet in a transport direction in a state where a leading end or a trailing end of the sheet is in contact with the upper surface. The drive mechanism moves the movable support portion to the vicinity of the center between the pair of fixed support portions to separate the front end or the rear end of the sheet from the upper surface, and then moves the movable support portion for a predetermined drying time. Wait
The ink jet recording apparatus according to claim 7, wherein the transport mechanism stops the transport of the sheet for the drying time. Further comprising a conveyance path that leads to the platen and has a curved portion that curves in a bending direction in which the leading edge or the trailing edge of the sheet contacts the upper surface of the platen;
The inkjet recording apparatus according to claim 7, wherein the conveyance mechanism temporarily stops conveyance of the sheet when the leading edge or the trailing edge of the sheet passes through the curved portion.   The inkjet recording apparatus according to claim 7, wherein the recording head performs pin check or test printing on the sheet.

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