JP2010012607A - Inkjet recording device and borderless recording method - Google Patents

Abstract

The present invention provides a means for reliably supporting a sheet by a support portion that reciprocates in the conveying direction in borderless recording, and realizing an increase in recording speed and a reduction in size of the apparatus.
A printer unit 11 includes a recording head 39 that selectively ejects ink droplets, a platen 42 having an upper surface 109 arranged to face the recording head 39, and a protrusion from the upper surface 109 of the platen 42 toward the recording head 39. In addition, the first support portion 102 and the second support portion 103 that are arranged at a separation distance 111 along the conveying direction 89, and the first support portion 102 and the second support portion 103 that are provided on the platen 42. , A movable portion 88 that can reciprocate along the transport direction 89, and a movable portion 88 that protrudes from the upper surface 109 of the platen 42 toward the recording head 39 and is separated by a separation distance 112 along the transport direction 89. A pair of third support parts 121 and 122 arranged, and a drive mechanism 105 that reciprocates the movable part 88 along the conveyance direction 89 are provided.
[Selection] Figure 7

Description

  The present invention relates to an inkjet recording apparatus and a marginless recording method for performing marginless recording by selectively ejecting ink droplets from a recording head onto a sheet.

  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 recording paper (sheet) 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 faces the recording head by a rib or the like provided on the platen or the platen. Supported by the state.

  By the way, in recent years, digital cameras have become widespread, and so-called home photo printing, in which image data taken with a digital camera is recorded on a dedicated recording sheet, has been widely performed. There is known a recording method for recording an image on a recording sheet without providing a margin at the periphery of the recording sheet when such a photographic image is recorded on a dedicated recording sheet. It is called a record. In borderless recording, ink droplets are ejected from the recording head to substantially the same position as the periphery of the recording paper or outside. For this reason, in borderless recording, ink droplets that have not landed on the recording paper may land on the platen. In order to prevent ink droplets that have landed on the platen from adhering to the back surface of the recording paper, the ink receiving portion of the platen is recessed from a rib that supports the recording paper. In borderless recording, control is performed so that ink droplets are not ejected from the recording head until the recording paper covers the ribs of the platen.

  In the borderless recording described above, the recording head ejects ink droplets in a wide area to increase the recording speed, and to support the recording paper in parallel to the recording head, a movable rib (movable support) Have been proposed (Patent Documents 1 to 4). In this configuration, a groove that cannot be contacted by the recording paper is formed at a position corresponding to the image recording area by the recording head in the rib provided on the platen and extending in the conveying direction, and the groove is slid in the conveying direction of the recording paper. A movable rib is provided. As a result, the ink droplets that have not landed on the recording paper in borderless recording land on the groove of the rib, so that the ink droplets in the groove do not adhere to the recording paper conveyed thereafter. Further, in the groove of the rib, the movable rib that is slid according to the position of the front end or the rear end of the recording paper supports the recording paper, so that the recording surface is parallel to the recording head on the groove. The paper is supported.

JP 2006-326990 A JP 2007-118480 A JP 2007-175971 A JP 2007-176093 A

  By the way, when image data such as photographs is recorded on a recording sheet, the amount of ink droplets ejected on the recording sheet generally increases. In addition, when recording is performed by transporting a so-called horizontal paper sheet along the long side in which the flow of fibers of the recording sheet intersects the long side of the recording sheet, the recording sheet is greatly bent due to the permeation of ink. Sometimes. Due to such various factors, the recording paper on which the ink droplets have landed may be bent on the platen. On the other hand, as described above, when the image recording area by the recording head is expanded in the transport direction in order to realize high-speed image recording, the width of the groove corresponding to the image recording area (distance in the transport direction) also increases. In so-called borderless recording, when the movable rib moves to the upstream side or downstream side in the conveying direction, the recording paper is not supported on the groove, and the recording paper bent on the platen contacts the bottom of the groove. There is a risk. Ink ribs that have not landed on the recording paper in borderless recording land on the groove of the rib, so that if the recording paper hangs down in the groove, ink may adhere to the recording paper and become dirty.

  If the portion where the movable rib supports the recording paper is lengthened in the transport direction with respect to the above-described problem, the distance that the movable rib must be slid to retract from between the ribs becomes long. That is, the area provided for retracting the movable rib on the upstream side and the downstream side in the conveyance direction from the rib becomes wider. As a result, the platen becomes large, which is contrary to the miniaturization of the apparatus.

  The present invention has been made in view of such circumstances, and an object of the present invention is to ensure that a sheet is reliably supported by a support portion that reciprocates along a conveying direction in so-called borderless recording. An object of the present invention is to provide means capable of realizing high speed and downsizing of the apparatus.

  (1) 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 disposed to face the recording head, and a protrusion protruding from the upper surface of the platen toward the recording head. And a first support part and a second support part that are disposed at a first distance along a transport direction in which the sheet is transported, and at least the first support provided on the platen. A movable part capable of reciprocating along the conveying direction between the first part and the second supporting part, and a sheet that is provided in the movable part and protrudes from the upper surface of the platen toward the recording head and supports the sheet. A plurality of third support portions arranged at a second distance shorter than the first distance along the direction, a transport mechanism for transporting the sheet to the platen, and a reciprocating motion of the movable portion along the transport direction A drive mechanism for, those having a.

  The ink jet recording apparatus can perform borderless recording. In borderless recording, a sheet is conveyed onto a platen arranged to face the recording head. The leading end side of the sheet conveyed on the platen is supported by the first support portion. Further, the leading end side of the conveyed sheet is supported by the third support portion. At this time, the third support unit is moved from the initial position to the first support unit side (upstream side in the transport direction). Further, the leading end side of the sheet may be supported by all or a part of the plurality of third support portions. When the movable portion is moved following the conveyance of the sheet, the third support portion follows the sheet while supporting the sheet. Since the plurality of third support portions are arranged to be separated along the conveyance direction, the sheet on the platen is supported at a plurality of locations with respect to the conveyance direction. Moreover, since the 2nd distance which is the distance between 3rd support parts is shorter than the 1st distance which is the distance between a 1st support part and a 2nd support part, between a 1st support part and a 2nd support part The sheet is supported by the plurality of third support portions. This prevents the sheet from sagging between the first support portion and the second support portion. When the sheet is further conveyed and the leading end side of the sheet is also supported by the second support part, the movable part does not follow the sheet and waits, for example, near the middle between the first support part and the second support part. . This standby position may be the same position as the initial position.

  When the sheet is further conveyed on the platen, the rear end side of the sheet is supported by the third support portion. At this time, the third support portion is moved from the standby position to the first support portion side (upstream side in the transport direction). The movable portion is moved following the conveyance of the sheet in a state where the rear end side of the sheet is supported by all of the plurality of third support portions. As the movable part moves, the third support part follows the sheet while supporting the sheet. Since the plurality of third support portions are arranged to be separated along the conveyance direction, the sheet on the platen is supported at a plurality of locations with respect to the conveyance direction. Further, since the second distance is shorter than the first distance, the sheet is supported by the plurality of third support portions between the first support portion and the second support portion. This prevents the sheet from sagging between the first support portion and the second support portion.

  In the present specification, unless otherwise specified, the “direction” is represented by a straight line having opposite directions such as + and −, for example. For example, it is represented by an arrow having one arrow head such as + or-.

  (2) The driving mechanism may include a plurality of the sheets on the leading end side of the sheet supported and conveyed by the first support part positioned upstream in the conveyance direction among the first support part and the second support part. Among these third support parts, the movable part may be made to follow the sheet while maintaining a state supported by a part of the third support parts arranged on the upstream side in the conveyance direction.

  The leading end side of the sheet conveyed on the platen and supported by the first support portion is supported by a part of the plurality of third support portions. Then, when the movable portion is moved following the conveyance of the sheet, the third support portion follows the sheet in a state where the leading end side of the sheet is supported by a part thereof. In this state, when borderless recording is performed on the leading edge side of the sheet, the ink droplets that have not landed on the leading edge of the sheet cause a part of the third supporting part that supports the sheet and the remaining third supporting part that does not support the sheet. Land between. Therefore, since ink droplets do not land on the remaining third support portion that does not support the sheet, even if the remaining third support portion supports the sheet thereafter, the sheet is not soiled. Further, when moving the third support portion to the first support portion side (upstream side in the conveyance direction), it is not necessary to move all of the third support portions outside the image recording region, so the moving region of the movable portion is shortened. In addition, since it is possible to perform borderless recording on the leading end side of the sheet using the entire area of the recording head, the recording speed can be increased and the apparatus can be downsized.

  (3) The first distance may be longer than a third distance along the conveyance direction in an area where the recording head can eject ink droplets, and the second distance may be shorter than the third distance.

  Since the first distance is longer than the third distance, the first support portion and the second support portion can support the sheet outside the image recording area. Therefore, even if ink droplets are ejected from the entire area of the recording head. The ink droplet does not land on the first support part and the second support part. Thereby, an increase in recording speed is realized. In addition, since the second distance is shorter than the third distance, the third support unit can support the sheet at a plurality of positions in the image recording area with respect to the conveyance direction, and thus the sheet is supported by the first support unit and the second support unit. It can prevent sagging between the parts.

  (4) The plurality of third support portions may be arranged in the first direction.

  As a result, the sheet can be supported at a plurality of locations in the width direction (first direction) of the sheet, so that the sheet is supported so that the gap between the recording head and the sheet is equal to the entire surface of the sheet. Image recording is realized.

  (5) The movable portion is disposed on the opposite side of the recording head with respect to the upper surface of the platen, and the plurality of third support portions protrude from the upper surface to the recording head through slits formed on the upper surface of the platen. You may do.

  (6) The borderless recording method according to the present invention includes a first support portion that protrudes from the upper surface of the platen toward the recording head and is disposed at a first distance along the conveyance direction in which the sheet is conveyed. A plurality of third supports that protrude from the upper surface of the platen toward the recording head and are spaced apart from each other by a second distance shorter than the first distance along the conveying direction. In the ink jet recording apparatus provided with a section, the sheet is supported on the leading end side of the sheet supported and transported by the first support section located upstream of the first support section and the second support section in the transport direction. While maintaining the state supported by a part of the plurality of third support portions on the upstream side in the conveyance direction, the ink droplets are selectively transferred from the recording head to the front end side of the sheet while the movable portion follows the sheet. Erupted into In the first step of performing recording, and on the rear end side of the sheet supported and conveyed by the second support part, the movable sheet is maintained while being supported by all of the plurality of third support parts. And a second step of performing edgeless recording by selectively ejecting ink droplets from the recording head to the rear end side of the sheet while causing the portion to follow the sheet.

  In the first step, while maintaining the state where the leading end side of the sheet is supported by a part of the plurality of third support portions on the upstream side in the conveyance direction, the movable portion follows the sheet and the leading end side of the sheet from the recording head When the ink droplets are selectively ejected to perform borderless recording, the ink droplets that have not landed on the leading edge of the sheet are partly supported by the third support portion that supports the sheet and the remaining third support that does not support the sheet. Land between the club. Therefore, since ink droplets do not land on the remaining third support portion that does not support the sheet, even if the remaining third support portion supports the sheet thereafter, the sheet is not soiled. Further, when moving the third support portion to the first support portion side (upstream side in the conveyance direction), it is not necessary to move all of the third support portions outside the image recording region, so the moving region of the movable portion is shortened. In addition, since it is possible to perform borderless recording on the leading end side of the sheet using the entire area of the recording head, the recording speed can be increased and the apparatus can be downsized.

  In the second step, ink droplets are selected from the recording head to the trailing edge of the sheet while maintaining the state where the trailing edge of the sheet is supported by all of the plurality of third support parts and causing the movable part to follow the sheet. When the marginless recording is performed by ejecting the ink, the ink droplets that have not landed on the trailing edge of the sheet land on the upstream side in the transport direction from the third support portion that supports the sheet. Therefore, the ink droplets do not land on the third support portion, so that the sheet is not soiled.

  (7) In the first step, borderless recording is performed using an area upstream of the remaining third support portion that does not support the sheet in the conveyance direction, in the area where the recording head can eject ink. May be.

  According to the present invention, the movable portion that can follow the conveyance of the sheet is provided with the plurality of third support portions arranged at the second distance along the conveyance direction. Between the two support portions, the sheet is supported at a plurality of locations with respect to the conveyance direction. This prevents the sheet from sagging between the first support portion and the second support portion, and thus prevents the sheet from being soiled during borderless recording.

  In addition, since the movable portion follows the sheet while maintaining the state where the leading end side of the sheet is supported by a part of the third supporting portions arranged on the upstream side in the conveyance direction among the plurality of third supporting portions, the third Since it is not necessary to move the entire support part outside the image recording area, the moving area of the movable part can be shortened, and the entire area of the recording head is used to perform borderless recording on the leading edge side of the sheet. can do. As a result, a higher recording speed and a smaller apparatus can be realized.

  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 configuration 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. FIG. 8 is an enlarged perspective view of the movable portion 88. FIG. 9 is an enlarged perspective view of the movable part 88 as seen from the bottom side. FIG. 10 is an enlarged perspective view of the drive mechanism 105. FIG. 11 is an enlarged cross-sectional view of the movable portion 88. FIG. 12 is a diagram illustrating the displacement of the movable portion 88 during the conveyance of the recording paper in the order of (a) to (d). 13 to 15 are diagrams showing the positional relationship between the recording paper 184 and the third support parts 121 and 122 in borderless recording.

[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. Accordingly, functions other than the print function in the multifunction device 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 recording 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. The printer unit 11 can 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 here.

  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. A slot portion 16 is provided on the front surface of the multifunction machine 10. 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 a predetermined size or less, such as A4 size. Of course, if a slide tray is provided in the paper feed tray 20 so that the tray surface can be enlarged, a recording paper (eg, legal size) larger than a predetermined size (eg, A4 size) of recording paper can be held in the paper feed tray 20. it can.

  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. Even if the recording paper fed from the paper feeding tray 20 by the rotation of the paper feeding roller 25 described later is fed by double feeding, these recording papers are separated and separated by the separation plate 22. The uppermost recording sheet is guided upward.

  The paper discharge tray 21 is disposed 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. The drive transmission mechanism 27 is configured such that a plurality of gears are engaged with each other, and the rotation of each gear is sequentially transmitted to transmit the drive of the LF 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 due to friction or electrostatic action (so-called double feeding). Restrained by contact.

  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 of the conveyance direction 89 from the curved portion 17 in the paper conveyance 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 (arrow 87 in FIG. 4) orthogonal to the recording sheet conveyance direction. Although not shown in FIG. 3, an ink cartridge is arranged for each color ink independently of the recording head 39 inside the multifunction machine 10. Cyan (C), magenta (M), yellow (Y), and black (Bk) color inks are supplied from the ink cartridges to the recording head 39 through the ink tubes 41 (see FIG. 4).

  In the present embodiment, the recording sheet is described as being conveyed only in the conveyance direction 89. However, in the inkjet recording apparatus according to the present invention, the sheet is normally conveyed (conveyance direction 89) according to various recording controls. Needless to say, it may be transported in the reverse transport (direction opposite to the transport direction 89).

  Although not shown in each figure, the recording head 39 has a plurality of nozzles on its lower surface. Each nozzle is arranged in one or two rows along the recording sheet conveyance direction 89 corresponding to each color ink 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 the number of each nozzle along the conveyance direction 89 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 arranged with a predetermined distance from the recording paper transport direction 89 and a direction perpendicular to the recording paper transport direction 89 (arrow 87) as a 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 of the recording paper conveyance direction 89 has a substantially flat plate shape. The length of the guide rail 43 in the longitudinal direction (arrow 87) is set longer than the reciprocating range of the carriage 38. The guide rail 44 disposed on the downstream side of the recording paper conveyance direction 89 is also substantially flat and has a length in the longitudinal direction equal to the length of the guide rail 43. Further, the edge 45 on the upstream side in the conveying direction 89 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 upstream end of the carriage 38 in the transport direction 89 is placed on the guide rail 43, and the downstream end of the carriage 38 in the transport direction 89 is placed on the guide rail 44. Although not shown in each figure, the carriage 38 sandwiches the edge portion 45 of the guide rail 44 by two gripping portions or the like. Accordingly, the carriage 38 is positioned with respect to the recording paper conveyance direction 89 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 89. During this sliding, the gripping part slides while sandwiching the edge 45.

  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 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 belt 49 is stretched between the drive pulley 47 and the driven pulley 48. A plurality of teeth are provided inside the 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 belt 49 moves circumferentially.

  The carriage 38 is connected to the belt 49. Accordingly, the carriage 38 reciprocates on the guide rails 43 and 44 in the horizontal direction 87 based on the circumferential motion of the belt 49. Since the recording head 39 is mounted on the carriage 38 as described above, the recording head 39 reciprocates in the horizontal direction 87 perpendicular to the recording sheet conveyance direction 89 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 later in detail, the platen 42 is provided with a movable portion 88 (see FIG. 8). The movable portion 88 is reciprocated along the recording sheet conveyance direction 89.

  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 the respective color inks of C, M, Y, and Bk. 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 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 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 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, the pinch roller 59, 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 59 are provided upstream of the image recording unit 24 in the conveying direction 89. The pinch roller 59 is provided so as to be movable in a direction in which the pinch roller 59 is in contact with or separated from the conveyance roller 60. The pinch roller 59 is urged so as to be in pressure contact with the conveying roller 60 by a coil spring. When the recording paper enters between the conveying roller 60 and the pinch roller 59, the pinch roller 59 is retracted against the urging force of the coil spring by the thickness of the recording paper, and presses the recording paper against the conveying roller 60. Thereby, the rotational force of the conveyance roller 60 is reliably transmitted to the recording paper. The transport roller 60 and the pinch roller 59 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 downstream of the image recording unit 24 in the transport direction 89. 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 according to the recording control, 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 movable 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.

  A registration sensor 95 is disposed on the sheet conveyance path 23 upstream of the conveyance roller 60 in the conveyance direction 89. The registration sensor 95 is a so-called mechanical sensor having a detector shown in FIG. 3 and an optical sensor not shown. 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 biased by a spring material (not shown) and always protrudes to the paper transport path 23. However, the elastic force that the spring material urges against the detector is such that the detector can be easily rotated only by abutting one recording sheet. Therefore, when the recording paper conveyed through the paper conveyance path 23 comes into contact with the detector, the detector rotates against the elastic biasing by the spring material and retracts from the paper conveyance path 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 includes a main board to which the flat cable 85 described above 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 PWM signal that energizes 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 movable unit 88.

  The ASIC 70 generates a PWM 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.

  The platen 42 mainly includes a frame 100, a first support portion 102 and a second support portion 103 provided on the frame 100, and a movable portion 88 slidably provided on the frame 100, and further includes a movable portion. A driving mechanism 105 for slidingly driving the 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 support portion 102 and a second support portion 103 are provided on the upper surface 109 of the frame 100. A plurality of first support portions 102 are provided in a row at predetermined intervals along the longitudinal direction (arrow 87) on the upstream end portion 94 side in the transport direction 89 on the upper surface 109. Each first support portion 102 protrudes upward as a longitudinal direction on the upper surface 109 as a thin plate-shaped rib, and a corner portion of the rib is chamfered.

  The second support portion 103 extends along the longitudinal direction (arrow 87) on the downstream end portion 96 side in the transport direction 89 on the upper surface 109. The second support portion 103 has a mountain shape in cross section along the conveyance direction 89 and protrudes upward toward the recording head 39. The second support portion 103 extends in the longitudinal direction of the frame 100 (arrow 87).

  The longitudinal direction (arrow 87) of the frame 100 is a direction orthogonal to the transport direction 89 along the upper surface 109 of the platen 42, and corresponds to the first direction in the present invention.

  The plurality of first support portions 102 and the second support portion 103 extending in the longitudinal direction (arrow 87) of the frame 100 are separated along the transport direction 89. In the present embodiment, a part of the upper surface 109 recognized as between each first support portion 102 and the second support portion 103 is referred to as a groove 116. The groove 116 extends on the upper surface 109 in the longitudinal direction of the platen 42 (arrow 87). The length of the groove 116 along the conveyance direction 89 (the separation distance 111 between each first support portion 102 and the second support portion 103) is the distance of the area occupied by each nozzle along the conveyance direction 89 in the recording head 39. It is supported. That is, the separation distance 111 is wider than the distance along the transport direction 89 in the region 114 (see FIG. 13) where ink droplets are ejected from each nozzle. This separation distance 111 corresponds to the first distance in the present invention. Further, the distance along the transport direction 89 in the region 114 where ink droplets are ejected from each nozzle of the recording head 39 corresponds to the second distance in the present invention.

  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. Most of the slits 119 extend from between the adjacent first support portions 102 to the downstream side in the transport direction 89 from the second support portion 103. Accordingly, the second support portion 103 is divided by the plurality of slits 119 with respect to the longitudinal direction of the platen 42 as a result. Through each slit 119, third support portions 121 and 122 of the movable portion 88 described later project upward from the upper surface 109 toward the recording head 39. However, the width of each slit 119 in the longitudinal direction (arrow 87) of the frame 100 is sufficient if the third support portions 121 and 122 of the movable portion 88 can pass therethrough. Therefore, in the platen 42 of the present embodiment, the second support portion 103 is divided by the plurality of slits 119, but the configuration of the platen when there is no movable portion 88, that is, a plurality of second support portions 103 is provided. Compared to the configuration of the platen that is not divided by the slits 119, there is no change in the function of supporting the recording paper.

  As shown in FIGS. 8 and 9, the movable portion 88 includes a base 120 formed in a box shape with an open lower surface, and a plurality of third support portions 121 and 122 provided on the base 120. The third support portions 121 and 122 are thin flat ribs, and protrude upward from the base 120 with the short direction of the base (the direction along the transport direction 89) as the long direction. The third support portions 121 and 122 project 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. That is, the movable portion 88 is disposed on the opposite side of the recording head 39 with respect to the upper surface 109 of the frame 100, and the third support portions 121 and 122 protrude toward the recording head 39. The detailed structure of the third support parts 121 and 122 will be described later.

  The movable part 88 can 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 portion 88.

  The drive mechanism 105 is for reciprocating the movable portion 88 along the recording sheet conveyance direction 89. The drive mechanism 105 transmits the rotation of the paper discharge roller shaft 92 to the movable 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 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 FIG. 10, the rotating plate 125 has a disk shape and can 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.

  The rotating plate 125 is driven and transmitted from the power transmission mechanism 124 to rotate forward or reverse. On the upper surface of the rotating plate 125, cams 136 and 137 having a shape perpendicular to the rotating direction of the rotating plate 125 are formed in a circumferential shape around the cylindrical shaft 127. Lock members 139 and 140 may be engaged with the vertical surface of 137, respectively. The forward rotation of the rotating plate 125 is restricted by the engagement of the lock member 139 and the cam 136, and the reverse rotation of the rotating plate 125 is restricted by the engagement of the lock member 140 and the cam 137. The rotation angle at which normal rotation or reverse rotation of the rotating plate 125 is regulated by the vertical surfaces of the cams 136 and 137 is set according to the operation described later. Therefore, the cams 136 and 137 are formed with a plurality of vertical surfaces corresponding to a predetermined rotation angle.

  As shown in FIG. 9, 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 with respect to the cylindrical shaft 127 (see FIG. 10). The guide groove 143 is formed along an Archimedean spiral formed vertically symmetrically with respect to a virtual axis passing through the center of the cylindrical shaft 127 along the back surface 142.

  As shown in FIG. 9, the lever member 126 is a crank-shaped flat plate that connects the base 120 of the movable 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 can be slid only in a direction along the recording sheet conveyance direction 89 by being fitted into the frame 100. Accordingly, the rotation of the rotating plate 125 is transmitted to the base 120 via the lever member 126, and the base 120 slides along the recording sheet conveyance direction 89.

  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 a displacement amount along the conveying direction 89 of the base 120. The displacement amount of the base 120 is set as an amount by which the third support portions 121 and 122 can reciprocate between the first support portion 102 and the second 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. Therefore, both end portions of the coil spring 157 are engaged with the lock member 139 and the frame 100 of the platen 42, respectively. 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 can be engaged with the cam 137 of the rotating plate 125 at a predetermined rotation angle.

  When the lock member 139 rotates about the support shaft 159, the engagement claw 161 is engaged with and disengaged from the cam 137. Note that the lock member 139 is urged in the engagement direction by the elastic urging of the coil spring 157 at all times when no external force is received. When the engaging claw 161 engages with the cam 137, the rotation plate 125 is prevented from rotating forward at a predetermined rotation angle. As a result, even if drive is transmitted from the drive mechanism 105, the rotating plate 125 is maintained at a predetermined rotation angle.

  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 tip 164 of the contact member 158, the lock member 139 is detached from the cam 137.

  The lock member 140 can be engaged with the cam 136 of the rotating plate 125 at a predetermined rotation angle. The lock member 140 is elastically urged by the coil spring 162, and is normally urged in the engaging direction without receiving external force. When the lock member 140 is engaged with the cam 136, the reverse rotation of the rotating plate 125 is stopped. The rotation angle of the rotating plate 125 with which the lock member 140 engages with the cam 136 is set corresponding to the initial position. The engagement between the lock member 140 and the cam 136 stops the rotation of the rotating plate 125 with respect to the drive transmission in which the paper discharge roller shaft 92 rotates in the reverse direction, while the paper discharge roller shaft 92 rotates forward (in the conveying direction 89). Corresponding rotation) The rotation of the rotating plate 125 is not restrained against drive transmission. Therefore, when the paper discharge roller shaft 92 is reversed, the lock member 140 and the cam 136 are engaged with each other and the rotation of the rotation plate 125 is stopped when the rotation plate 125 rotates to the initial position. Thereby, the rotating plate 125 is initialized.

[Third support parts 121, 122]
As shown in FIGS. 8 and 11, a pair of third support portions 121 and 122 are provided on the upper surface of the base 120 so as to be spaced apart in the transport direction 89. As shown in FIG. 8, the pair of third support parts 121 and 122 are arranged at predetermined intervals along the longitudinal direction (arrow 87) of the base 120. Each of the third support portions 121 and 122 has substantially the same shape, and has a thin rib shape extending along the recording sheet conveyance direction 89 in a state assembled to the frame 100. Each of the third support portions 121 and 122 protrudes from the base 120 toward the recording head 39, and the protruding tip has a mountain shape. The thickness of each of the third support parts 121 and 122 corresponds to the width of the slit 119, and the arrangement of each of the pair of third support parts 121 and 122 corresponds to the arrangement of the plurality of slits 119.

  In each third support portion 121, the front end surface extending along the conveyance direction 89 is roughly divided into a first inclined surface 130, a support surface 131, and a second inclined surface 132 from the upstream side of the conveyance direction 89. The support surface 131 is a substantially horizontal plane. The first inclined surface 130 is a plane that descends at a predetermined angle with respect to the vertical direction from the upstream end of the support surface 131 in the transport direction 89. The second inclined surface 132 is a plane that descends at a predetermined angle with respect to the vertical direction from the downstream end of the conveying direction 89 on the support surface 131. In addition, although the reference code | symbol is not attached | subjected, the both side surfaces used as the upstream end and downstream end of the conveyance direction 89 in each 3rd support part 121 are planes along a perpendicular direction. In each of the third support portions 121 having such a shape, the recording sheet is supported from below by the support surface 131. Further, since the recording sheet supported by the support surface 131 maintains a flat posture by its waist, it does not contact the first inclined surface 130 and the second inclined surface 131.

  The front end surface extending along the transport direction 89 in each third support part 122 is roughly divided into a first inclined surface 133, a support surface 134, and a second inclined surface 135 from the upstream side of the transport direction 89. The support surface 134 is a substantially horizontal plane. The first inclined surface 133 is a plane that descends at a predetermined angle with respect to the vertical direction from the upstream end of the support surface 134 in the transport direction 89. The second inclined surface 135 is a plane that descends at a predetermined angle with respect to the vertical direction from the downstream end of the support surface 134 in the transport direction 89. In addition, although the referential mark is not attached | subjected, the both side surfaces used as the upstream end and downstream end of the conveyance direction 89 in each 3rd support part 122 are planes along a perpendicular direction. In each of the third support portions 122 having such a shape, the recording sheet is supported from below by the support surface 134. Further, since the recording sheet supported by the support surface 134 maintains a flat posture by its waist, it does not contact the first inclined surface 133 and the second inclined surface 135.

  As shown in FIG. 11, the pair of third support parts 121 and 122 are separated from each other in the conveyance direction 89 by a separation distance 112. The separation distance 112 is a distance along the transport direction 89 from the downstream end of the support surface 131 in the transport direction 89 to the upstream end of the support surface 134 in the transport direction 89. The separation distance 112 is shorter than the distance along the transport direction 89 in the region 114 (see FIG. 13) where ink droplets are ejected from each nozzle in the recording head 39 described above. As a result, the separation distance 112 is shorter than the separation distance 111 (see FIG. 7) between the first support portion 102 and the second support portion 103. Therefore, as shown in FIG. 7, when the movable portion 88 is positioned substantially at the center between the first support portion 102 and the second support portion 103, the first support portion from the upstream side with respect to the transport direction 89. 102, the third support part 121, the third support part 122, and the second support part 103 are arranged in this order at a predetermined separation distance.

  The separation distance 112 includes a distance 115 along the transport direction 89 on the inclined surface 132, a distance 116 along the transport direction 89 on the inclined surface 133, and an ink droplet ejected from the recording head 39 to the leading edge of the recording paper 184. It is larger than the sum of the safety margin 117. That is, (separation distance 112)> (distance 115) + (distance 116) + (safety margin 117). Here, in the so-called borderless recording, the safety margin 117 is caused by various errors such as a conveyance error of the recording paper 184 and an ejection timing error when ink droplets are ejected from the recording head 39 to the tip of the recording paper 184. This is the distance from the leading edge of the recording paper 184 that is assumed to possibly not land on the leading edge of the recording paper 184 to the downstream side in the transport direction 89.

  Furthermore, in other words, in other words, the separation distance 112 is the most downstream position in the portion where the third support portion 121 upstream of the transport direction 89 supports the recording paper 184 and the third downstream position of the transport direction 89. This is the distance along the conveyance direction 89 from the most upstream position at the portion where the support unit 122 supports the recording paper. The distance 115 is a distance along the conveyance direction 89 from the most downstream position in the portion where the third support portion 121 upstream of the conveyance direction 89 supports the recording paper 184 to the most downstream position in the third support portion 121. The distance 116 is a distance along the conveyance direction 89 from the most downstream position in the third support portion 122 downstream in the conveyance direction 89 to the most downstream position in the portion where the third support portion 122 supports the recording paper 184.

  By setting the separation distance 112 to the relationship described above, it is assumed that the operation control of the movable unit 88 is performed so that the leading edge of the recording sheet 184 is positioned immediately above the downstream end of the conveying direction 89 on the inclined surface 132 in borderless recording. Even if the above-described various errors occur, the ink droplets ejected from the recording head 39 toward the leading edge of the recording paper 184 cause the inclined surface 132 or the third third surface of the third support portion 121 to be used. It does not adhere to the inclined surface 133 of the support part 122.

[Borderless recording method]
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, 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. 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 end of the recording sheet comes into contact with the conveying roller 60 and the pinch roller 59. Since the transport roller 60 is rotated in the direction opposite to the transport direction 89, the leading edge of the recording paper is not sandwiched between the transport roller 60 and the pinch roller 59 in this state, and the recording paper is held by the transport roller 60 and the pinch roller 59. The resist process is performed in a contact state. After the registration of the recording paper, the control unit 64 reverses the rotation of the LF motor 71 and rotates the transport roller 60 in the transport direction 89. As a result, the registration-processed recording paper is nipped between the conveyance roller 60 and the pinch roller 59. Then, the recording paper is conveyed onto the platen 42.

  The sheet discharge roller 62 also rotates during the period from paper feeding to registration processing. However, as described above, the rotation of the rotating plate 125 is stopped by the lock member 140 when the rotating plate 125 reaches the initial position. As a result, a torque of a certain level or more is generated in the torque limiter 148 to cause slipping, and only the paper discharge roller 62 is reversed while the rotating plate 125 is stopped at the initial position.

  Subsequently, an operation corresponding to the first step in the borderless recording method according to the present invention will be described. In the first step, the state where the leading end side of the recording paper 184 is supported by the first support portion 102 and the third support portion 121 is maintained, the movable portion 88 follows the recording paper 184, and the recording paper 184 is conveyed. In the process, ink droplets are selectively ejected from the recording head 39 to the leading end side of the recording paper 184.

  More specifically, when the leading end of the recording paper 184 reaches the conveyance roller 60, the movable portion 88 is positioned at the center of the platen 42, which is the initial position (FIG. 12A), and the base end portion 146 of the lever member 126 is used. Is arranged at an initial position in the guide groove 143 of the rotating plate 125. In order to facilitate understanding of the displacement of the movable portion 88, FIGS. 12A to 12D are views of the platen 42 viewed from the back side, and the back cover of the platen 42 is further removed. It is shown in the figure.

  After the registration processing, the LF motor 61 is rotated forward and the transport roller 60 and the paper discharge roller 61 rotate in the transport direction 89. The recording paper 184 is nipped by the transport roller 60 and the pinch roller 59 and transported in the transport direction 89. . When the leading edge of the recording paper 184 reaches the platen 42, the LF motor 71 is intermittently driven. Further, the CR motor 73 is driven at a predetermined timing before and after the leading edge of the recording paper 184 reaches the platen 42, and the carriage 38 comes into contact with the contact member 158. When the contact member 158 is rotated, the engagement between the engagement claw 161 of the lock member 139 and the cam 137 is released, and the rotating plate 125 can be rotated. Therefore, after the registration process, when the discharge roller shaft 92 is rotated 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. Then, the rotation of the rotating plate 125 is transmitted to the movable portion 88 by the lever member 126, and the third support portions 121 and 122 slide between the first support portion 102 and the second support portion 103 together with the movable portion 88.

  Before the leading edge of the recording paper 184 passes through the first support portion 102, the movable portion 88 is slid to the upstream side in the transport direction 89 and stops. That is, when the rotating plate 125 is rotated by a predetermined rotation angle (for example, 90 °) from the initial position, the engaging claw 161 is engaged with the cam 137 again, and the rotation of the rotating plate 125 is again stopped. At this time, the 3rd support part 121 located in the upstream of the conveyance direction 89 among a pair of 3rd support parts 121 and 122 will be in substantially the same position as the 1st support part 102 (Fig.13 (a)). On the other hand, the third support part 122 is located downstream of the first support part 102 in the transport direction 89, and the position of the third support part 122 is in a region 114 where ink droplets are ejected from the recording head 39. That is, only the third support part 121 located upstream of the transport direction 89 out of the pair of third support parts 121 and 122 is moved outside the region 114 where the ink droplets are ejected.

  As shown in FIG. 13B, 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 support portion 102 and the third support portion 121. In other words, the recording paper 184 covers the first support part 102 and the third support part 121 from above. At this time, the leading edge of the recording paper 184 is positioned between the pair of third support portions 121 and the third support portion 122.

  Thereafter, the CR motor 73 is driven at a predetermined timing, and the carriage 38 comes into contact with the contact member 158. As a result, the lock member 139 is rotated in the same manner as described above, the engagement between the engagement claw 161 and the cam 137 is released, and the rotation plate 125 can be rotated again. As a result, the third support parts 121 and 122 together with the movable part 88 are displaced downstream in the transport direction 89 by the intermittent drive of the LF motor 71. 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 has its leading end positioned between the pair of third support portion 121 and the third support portion 122. In this state, the platen 42 is conveyed. In this conveyance process, the recording paper 184 is supported by the first support portion 102 and the third support portion 121. The relative positional relationship among the movable portion 88, the rotating plate 125, and the lever member 126 changes in the order of FIGS.

  As shown in FIGS. 12B to 12D, when the rotating plate 125 rotates again, the lever member 126 swings about the intermediate portion 147 as a swing center, and as a result, the movable portion 88 moves in the conveyance direction. Move downstream of 89. When the rotation angle of the rotating plate 125 reaches a predetermined angle (for example, 270 °) from the initial position, the third support portions 121 and 122 slide to the vicinity of the second support portion 103. Further, when the rotating plate 125 rotates, the lever member 126 swings around the intermediate portion 147 as the swing center, and the movable portion 88 moves upstream in the transport direction 89. When the rotating plate 125 makes one rotation from the initial position, the movable portion 88 returns to a position corresponding to the initial position of the rotating plate 125.

  As shown in FIGS. 14A and 14B, while the recording paper 184 is intermittently conveyed, ink droplets of each color are selectively ejected from the recording head 39 that is slid with the carriage 38 for recording. Land on the paper 184. In borderless recording, ink droplets are ejected to at least the peripheral edge of the recording paper 184. On the leading end side of the recording paper 184, the recording head 39 can eject ink droplets as the recording paper 184 is intermittently conveyed. Ink droplets are ejected only on the upstream side of the transport direction 89 from a position corresponding to the leading edge of the recording paper 184 in the region 114.

  As described above, when the movable portion 88 is slid to the upstream side in the transport direction 89 and stops, only the third support portion 121 on the upstream side in the transport direction 89 out of the pair of third support portions 121 and 122. Is moved outside the region 114 where ink droplets are ejected. The recording sheet 184 covers only the third support portion 121 of the pair of third support portions 121 and 122 from the upper side. Therefore, when the leading edge of the recording paper 184 covers the third support portion 121 and enters the region 114, the ink droplets are immediately ejected from the recording head 39 to perform image recording. That is, borderless recording is performed on the recording paper 184 by using the entire area 114 of the recording head 39 while corresponding to the position of the tip of the recording paper 184.

  As shown in FIGS. 14A and 14B, the leading end of the recording paper 184 is located between the third support portion 121 and the third support portion 122. The positional relationship between the leading end of the recording paper 184 and the third support portions 121 and 122 is maintained while the third support portions 121 and 122 are slid in the transport direction 89. As described above, since the third support portion 121 is covered with the recording paper 184, even if there is an ink droplet that does not land on the recording paper 184, the ink droplet does not adhere to the third support portion 121. Absent.

  On the other hand, since the leading edge of the recording paper 184 is between the third support portion 121 and the third support portion 122, even if there is an ink droplet that does not land on the recording paper 184, the ink droplet remains in the third support portion 121. And land on the base 120 between the first support portion 122 and the third support portion 122. Further, as described above, ink droplets are ejected from the recording head 39 only from the position corresponding to the leading edge of the recording paper 184 on the upstream side in the transport direction 89. In other words, ink droplets are ejected only from the region 114 upstream of the transport direction 89 from the third support portion 122 that does not support the leading end side of the recording paper 184 in the region 114 of the recording head 39. Accordingly, since no ink droplets are ejected from the recording head 39 toward the third support portion 122, no ink droplets adhere to the third support portion 122.

  When the rotating plate 125 returns to the initial position, the engaging claw 161 is engaged with the cam 137 as described above, and the rotation of the rotating plate 125 is stopped. 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, 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 rotated. As a result, as described above, the engagement between the engagement claw 161 of the lock member 139 and the cam 137 is released, and the rotating plate 125 can be rotated.

  As the rotating plate 125 rotates forward, the third support parts 121 and 122 slide between the first support part 102 and the second support part 103. The relative positional relationship among the movable portion 88, the rotating plate 125, and the lever member 126 changes again in the order of FIGS. More specifically, as shown in FIG. 15A, when the third support parts 121 and 122 move to the upstream side in the conveying direction 89, the rotating plate 125 is engaged by the engagement of the engagement claw 161 and the cam 137. , And the third support part 121 becomes substantially the same position as the first support part 102 with respect to the transport direction 89, and the movable part 88 stops. Then, the carriage 38 comes into contact with the contact member 158 before the rear end of the recording paper 184 passes through the first support portion 102. As a result, the engagement between the engagement claw 161 and the cam 137 is released, and the rotating plate 125 can be rotated. As a result, the movable portion 88 to which the driving force from the LF motor 71 is transmitted moves to the movable portion 88, and the third support portions 121 and 122 also slide to the downstream side in the transport direction 89 along with this. Further, the relative positional relationship among the movable portion 88, the rotating plate 125, and the lever member 126 changes in the order of FIGS.

  As shown in FIGS. 15A and 15B, 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 rear end of the recording paper 184 is a pair of thirds. It is conveyed on the platen 42 in a state where both the support parts 121 and 122 are covered. When the trailing edge of the recording sheet 184 is conveyed from the first support unit 102 to the second support unit 103, the recording sheet 184 is supported by the third support units 121 and 122. A pair of 3rd support parts 121 and 122 are spaced apart and arrange | positioned along the conveyance direction 89, The separation distance 112 (refer FIG. 11) is the separation distance of the 1st support part 102 and the 2nd support part 103. 111 (see FIG. 7), the rear end side of the recording paper 184 is between the first support portion 102 and the second support portion 103 with respect to the conveying direction 89 with respect to the pair of third support portions 121 and 122. Supported in two places.

  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, the third support portion 121, which is covered by the recording paper 184, No ink droplets adhere to 122. Then, 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, 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 so-called bordered recording in which there is no image to be recorded around the recording paper. In such bordered recording, all ink droplets ejected from the recording head 39 toward the recording paper 184 land on the recording paper 184, so that the movable portion 88 does not need to move following the recording paper 184. . Accordingly, the carriage 38 is not brought into contact with the contact member 158, and the rotating plate 125 remains stopped at the initial position. Since the movable portion 88 is always disposed at the center of the platen 42, the leading end or the trailing end of the recording paper 184 does not hang between the first support portion 102 and the second support portion 103, and the recording head 39 The distance (head gap) from the recording paper 184 is kept constant.

[Operational effects of this embodiment]
As described above, in the borderless recording, the printer unit 11 uses the third end of the recording sheet 184 conveyed on the platen 42 on the upstream side of the conveying direction 89 in the pair of third support units 121 and 122. Since the movable unit 88 is supported only by the support unit 121 and follows the intermittent conveyance of the recording paper 184, when borderless recording is performed on the front end side of the recording paper 184, it does not land on the front end side of the recording paper 184. The ink droplets land between the third support part 121 and the third support part 122. Accordingly, since no ink droplets adhere to the third support portion 122, the recording paper 184 is not soiled with ink even if the rear end side of the recording paper 184 is supported by the third support portion 122.

  In addition, since it is not necessary to move both the pair of third support parts 121 and 122 to the outside of the area 114 where the ink droplets are ejected from the recording head 39, the moving area of the movable part 88 can be shortened and the recording can be performed. Since borderless recording can be performed on the recording paper 184 using the entire area of the recording head 39 in correspondence with the position of the leading end of the paper 184, the recording speed can be increased and the apparatus can be downsized.

  Further, in the borderless recording, the printer unit 11 supports the rear end side of the recording paper 184 together with the pair of third support parts 121 and 122 so that the movable unit 88 follows the intermittent conveyance of the recording paper 184. The recording paper 184 is supported at a plurality of locations with respect to the conveyance direction 89. This prevents the recording paper 184 from sagging between the first support portion 102 and the second support portion 103.

  Further, since the separation distance 111 between the first support portion 102 and the second support portion 103 is longer than the distance along the conveyance direction 89 in the region 114 of the recording head 39, the first support portion 102 and the second support portion 102 are outside the region 114. 2 The support unit 103 supports the recording paper 184. Therefore, even if ink droplets are ejected from all of the region 114 of the recording head 39, the ink droplets do not adhere to the first support portion 102 and the second support portion 103, so that the recording speed can be increased.

  In addition, since the separation distance 112 between the pair of third support portions 121 and 122 is shorter than the distance along the conveyance direction 89 of the area 114 of the recording head 39, the third distance is set at two locations in the area 114 with respect to the conveyance direction 89. Support portions 121 and 122 support the recording paper 184. This prevents the recording paper 184 from sagging between the first support portion 102 and the second support portion 103.

  Further, since the pair of third support portions 121 and 122 are arranged in a direction (arrow 87) perpendicular to the transport direction along the upper surface 109 of the platen 42, the width direction (arrow 87) of the recording paper 184 is provided. On the other hand, the recording paper 184 can be supported at a plurality of locations. As a result, the gap between the recording head 39 and the recording paper 184 is constant with respect to the entire surface of the recording paper 184, so that highly accurate image recording is realized.

  In the above-described embodiment, when the leading edge of the recording paper 184 is transported to the platen 42 in borderless recording, the third support member 121, 122 is located on the upstream side in the transport direction 89 among the pair of third support portions 121, 122. Only the support part 121 supports the leading end side of the recording paper 184, and the leading end of the recording paper 184 is positioned between the third support part 121 and the third support part 122, but a pair of third support parts Both 121 and 122 may support the leading end side of the recording paper 184.

  In order for both of the pair of third support parts 121 and 122 to support the leading end side of the recording paper 184, both the pair of third support parts 121 and 122 are disposed outside the region 114 where ink droplets are ejected from the recording head 39. Although the recording paper 184 is supported at two locations with respect to the conveying direction 89 by the pair of third support parts 121 and 122, the leading end side of the recording paper 184 is the first support part 102 and the second support. There is an advantage that it is prevented from sagging with the portion 103.

  In the above-described embodiment, the pair of third support parts 121 and 122 is shown as the third support part in the present invention. However, the third support part in the present invention is not limited to a pair, and is transported. Three or more in the direction may be constituted by a plurality of ribs arranged in a row with a separation distance 112.

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 configuration 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. FIG. 8 is an enlarged perspective view of the movable portion 88. FIG. 9 is an enlarged perspective view of the movable part 88 as seen from the bottom side. FIG. 10 is an enlarged perspective view of the drive mechanism 105. FIG. 11 is an enlarged cross-sectional view of the movable portion 88. FIG. 12 is a diagram illustrating the displacement of the movable portion 88 during the conveyance of the recording paper in the order of (a) to (d). FIG. 13 is a diagram illustrating a positional relationship between the recording sheet 184 and the third support parts 121 and 122 in borderless recording. FIG. 14 is a diagram illustrating a positional relationship between the recording sheet 184 and the third support portions 121 and 122 in borderless recording. FIG. 15 is a diagram illustrating a positional relationship between the recording sheet 184 and the third support portions 121 and 122 in borderless recording.

Explanation of symbols

11: Printer unit (inkjet recording apparatus)
25 ... Paper feed roller (conveyance mechanism)
39 ... Recording head 42 ... Platen 59 ... Pinch roller (conveyance mechanism)
60: Conveying roller (conveying mechanism)
62... Discharge roller (conveying mechanism)
63 ... spur (conveyance mechanism)
88 ... movable part 102 ... first support part 103 ... second support part 105 ... drive mechanism 109 ... upper surface 119 ... slits 121 and 122 third support part

Claims (7)

A recording head that selectively ejects ink droplets;
A platen whose upper surface is disposed opposite to the recording head;
A first support portion and a second support portion that protrude from the upper surface of the platen toward the recording head to support the sheet, and are disposed at a first distance along a conveyance direction in which the sheet is conveyed;
A movable part provided on the platen and capable of reciprocating between the first support part and the second support part along the conveying direction;
A plurality of second portions provided on the movable portion and projecting from the upper surface of the platen toward the recording head to support the sheet, and arranged at a second distance shorter than the first distance along the conveying direction. 3 support parts;
A transport mechanism for transporting a sheet to the platen;
An ink jet recording apparatus comprising: a drive mechanism that reciprocates the movable portion along a conveyance direction.   The drive mechanism is configured such that the sheet is supported by the first support portion positioned on the upstream side in the conveyance direction among the first support portion and the second support portion, and the sheet is a plurality of the third support portions. The inkjet recording apparatus according to claim 1, wherein the movable unit is made to follow the sheet while maintaining a state of being supported by a part of the third support unit disposed on the upstream side in the conveyance direction of the support unit.   3. The ink jet recording apparatus according to claim 1, wherein the first distance is longer than a third distance along a transport direction in an area where the recording head can eject ink droplets, and the second distance is shorter than the third distance. .   The inkjet recording apparatus according to any one of claims 1 to 3, wherein the plurality of third support portions are arranged in a row in the first direction. The movable part is disposed on the opposite side of the recording head with respect to the upper surface of the platen,
5. The inkjet recording apparatus according to claim 1, wherein the plurality of third support portions protrude from the upper surface to the recording head through a slit formed on the upper surface of the platen. A movable portion that protrudes from the upper surface of the platen toward the recording head and reciprocates between the first support portion and the second support portion that are disposed at a first distance along the conveyance direction in which the sheet is conveyed. In the inkjet recording apparatus provided with a plurality of third support portions that protrude from the upper surface of the platen toward the recording head and are arranged at a second distance shorter than the first distance along the conveying direction.
The sheet is transported among the plurality of third support sections on the leading end side of the sheet supported and transported by the first support section positioned upstream in the transport direction among the first support section and the second support section. In this example, while maintaining the state of being supported by a part of the upstream side in the direction, the movable portion follows the sheet, and ink droplets are selectively ejected from the recording head to the leading end side of the sheet to perform borderless recording. One step,
On the rear end side of the sheet supported and conveyed by the second support part, the sheet is supported by all of the plurality of third support parts while keeping the movable part following the sheet, And a second step of performing marginless recording by selectively ejecting ink droplets from the recording head to the rear end side of the sheet.   7. In the first step, borderless recording is performed using an area upstream of the remaining third support portion that does not support the sheet in the conveyance direction in the area where the recording head can eject ink. The borderless recording method described in 1.

Images