JP2016221723A - Printer and platen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printer capable of reliably performing a margin-less print, and suppressing stain on a rear surface of a sheet with an ink mist generated when the ink is discharged in the outside of a sheet end.SOLUTION: A platen includes a suction part 18 for sucking the sheet with a negative pressure so as to bring the sheet into contact with a support part 14. The printer includes the suction part 18 for applying the negative pressure so as to bring the sheet into contact with the support part, and ink receiving parts 31A, 31B and 34 for receiving the ink discharged in the outside of the sheet, and in the support part, slit holes 423 for sucking air are formed in a part of a side wall part 140A adjacent to the ink receiving parts.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an inkjet printing apparatus including a platen that supports a sheet.

  Patent Document 1 discloses an ink jet printing apparatus capable of performing so-called “marginless printing” in which an image is formed without providing a margin at an end of a sheet. This apparatus uses a suction platen that adsorbs a sheet by negative pressure.

JP 2006-021475 A

  In Patent Document 1, when performing borderless printing on the trailing edge of the sheet, the sheet is adsorbed to the adsorption portion of the platen. However, when performing borderless printing on the leading edge of the sheet, the leading edge of the sheet has not yet reached the suction portion and is not sucked. For this reason, when the sheet is introduced, the lifting of the leading edge of the sheet cannot be suppressed, and the ink is landed while the sheet is lifted. As a result, there is a possibility that the image quality at the raised portion is deteriorated, or the sheet comes into contact with the print head and the sheet becomes dirty. Furthermore, ink that is discarded outside the edge of the sheet during borderless printing may float as a mist-like ink mist and adhere to the back surface of the sheet.

  The present invention provides a printing apparatus and a platen capable of reliably performing borderless printing and suppressing the back surface of the sheet from being stained with ink mist generated when ink is ejected to the outside of the sheet edge. For the purpose of provision.

  An embodiment of the present invention that solves the above-described problem is a printing apparatus that includes a print head that ejects ink and a platen that supports the sheet so as to face the print head, and the platen supports the sheet. A support unit; a suction unit that sucks the sheet with a negative pressure so as to adsorb the sheet to the support unit; and the print unit disposed adjacent to the support unit in the sheet conveyance direction and outside the sheet supported by the support unit. An ink receiving portion that receives ink ejected from the head, and the support portion has a slit hole that sucks air in a part of a side wall portion adjacent to the ink receiving portion. Features.

  According to the present invention, it is possible to reliably perform borderless printing, and it is possible to suppress contamination of the back surface of the sheet with ink mist generated when ink is ejected outside the sheet edge.

1 is a perspective view illustrating an overall configuration of a printing apparatus main body. It is a vertical side view of a printing apparatus. It is the expansion perspective view which looked at a part of platen from diagonally upward. It is a vertical side view which shows a part of platen and its peripheral structure. It is an enlarged plan view showing a part of the platen. It is a vertical front view of a platen. It is an enlarged view which shows a part of platen. It is an enlarged view which shows a part of platen. It is an expansion perspective view which shows a part of platen in 2nd Embodiment. It is a vertical side view which expands and shows a part of platen.

  An embodiment of a printing apparatus according to the present invention will be described. Hereinafter, an example of a serial type inkjet printing apparatus that performs printing by reciprocating a print head capable of ejecting ink in a direction intersecting the sheet conveyance direction with respect to a sheet intermittently conveyed in a certain direction will be described. To do. The present invention is not limited to a serial type printing apparatus, but can be applied to a line printing apparatus that performs continuous printing using a long print head. The printing apparatus is not limited to a single-function printing apparatus, but can be applied to a multifunction printer having both a copy function and a facsimile function.

  The configuration of the printing apparatus 1 in the present embodiment will be described. FIG. 1 is a perspective view showing the overall configuration of the printing apparatus 1, and FIG. 2 is a longitudinal side view of the printing apparatus 1 shown in FIG. A feeding device 40 is provided on the back side of the printing apparatus 1. The feeding device 40 separates the sheets one by one from the bundle of cut sheets (hereinafter simply referred to as “sheets”) stacked on the feeding tray 5 by the rotation of the feeding roller 6, and transport means such as the transport roller 7. To feed. The printing apparatus 1 is provided with a carriage 4 on which a print head 3 that can eject ink is mounted. The carriage 4 is supported so as to be capable of reciprocating along a carriage guide shaft 41 and a carriage rail 42 provided along a direction (X direction) intersecting (orthogonal in the embodiment) with respect to the sheet conveyance direction (Y direction). Has been. The X direction is the carriage movement direction and also the sheet width direction of the conveyed sheet. The Y direction is the sheet conveying direction.

  One sheet separated and fed by the feeding device 40 from the sheet bundle loaded on the feeding tray 5 is printed by a first conveying roller pair (conveying means) including a conveying roller 7 and a pinch roller 8. 3 is conveyed onto a platen 9 that supports a sheet at a position opposite to the platen 9. Here, the carriage 4 on which the print head 3 is mounted moves in the X direction, and ink is ejected from the print head 3 toward the sheet. A sheet detection sensor for detecting the end of the sheet is provided on one side surface of the carriage 4. Based on the detection output from the sheet detection sensor, the relative position between the sheet and the print head 3 and the printing on the sheet are performed. The start timing and the like are determined.

  When printing for one scanning is performed on the sheet, the sheet is conveyed by a predetermined amount in the Y direction by the first conveying roller pair. By repeating the movement of the print head 3 and the conveyance of the sheet as described above, printing on the sheet is performed in a serial manner.

  The sheet 2 on which printing has been completed is placed on the discharge tray 12 by a second conveyance roller pair (conveyance means) including a discharge roller 10 and a spur 11 that is disposed downstream of the platen 9 in the sheet conveyance direction (Y direction). Discharged.

Next, the structure of the platen 9 will be described. FIG. 3 is an enlarged perspective view of a part of the platen shown in FIG. 1 as viewed obliquely from above. FIG. 4 is a longitudinal side view showing the platen shown in FIG. 3 and its peripheral portion. Here, a path for sucking ink mist generated when the vicinity of the front end of the sheet is printed is shown.
As shown in FIGS. 2 and 4, the platen 9 is disposed between a first conveyance roller pair including a conveyance roller 7 and a pinch roller, and a second conveyance roller pair including a discharge roller 10 and a spur 11. ing. The platen 9 supports the sheet 2 conveyed by the first and second conveyance roller pairs on a surface (back surface) opposite to the print surface.

  The platen 9 has a sheet support portion (support portion) 14 that can support the back surface of the sheet while suppressing the floating and bending of the sheet 2 in order to keep the gap between the discharge port forming surface 3a of the print head 3 and the sheet 2 appropriate. Is formed. A plurality of sheet support portions 14 are formed along the longitudinal direction (X direction) of the platen 9.

  FIG. 5 is an enlarged view showing a part of the platen 9 shown in FIG. The sheet support portion 14 is formed in a rectangular frame shape by rib-like convex portions. An adsorption recess (suction part) 17 that forms a recess that is one step lower than the sheet support surface 13 is formed in the upper part of the sheet support part 14. A suction hole 18 penetrating the platen 9 is formed on the bottom surface of the suction recess 17. The suction hole 18 communicates with negative pressure generating means 19 such as a fan.

  An upstream side sheet support portion 32 that supports the sheet 2 conveyed from the conveyance roller 7 from the back surface is formed further upstream than a later-described rear end ink discarding groove 31 </ b> B formed in the platen 9. Further, a downstream side sheet support portion 33 that supports the sheet 2 conveyed by the discharge roller 10 from the back surface is formed further downstream than a later-described leading edge ink discarding groove 31 </ b> A formed on the platen 9. Each of the upstream sheet support portion 32 and the downstream sheet support portion 33 is formed by a rib-like convex portion extending along the sheet conveyance direction (Y direction), as shown in FIG. , A plurality of them are arranged in the X direction at regular intervals.

  Further, the upstream sheet support part 32 and the downstream sheet support part 33 are formed so that the positions of the tops thereof are the same height as the sheet support surface (contact part) 13 of the sheet support part 14 described above. The upstream sheet support portion 32 and the downstream sheet support portion 33 prevent the sheet 2 from dropping or getting caught when the leading end or the trailing end of the sheet 2 passes through the sheet supporting portion 14 or each roller. Fulfills the function.

  In order to reliably perform so-called borderless printing in which printing is performed on the entire sheet 2 without providing a margin at the periphery of the sheet, it is necessary to eject ink to the outside of the end portion of the sheet 2. In addition, in the ink jet printing apparatus, so-called preliminary ejection, in which ink is ejected to the outside of the sheet 2 immediately before the printing operation, is performed in order to stabilize the ink ejection performance of the print head 3. Such ink ejected to the outside of the sheet 2 is received by an ink receiving portion formed on the platen 9. In this example, as the ink receiving portion, the leading edge ink discarding groove 31A for receiving ink ejected outside the sheet leading edge 2a and the trailing edge ink discarding groove 31B for receiving ink ejected outside the sheet trailing edge 2b are used. And are provided. Further, in this example, left and right end ink discarding grooves 34 that receive ink discharged to the outside of the left and right ends (sheet side ends) of the sheet 2 in the sheet width direction are provided as the ink receiving portions.

  FIG. 4 is a longitudinal side view showing a part of the platen 9 and its peripheral structure. Here, an ink discard groove (first ink receiving portion) 31A for the front end of the platen 9 and an ink discard groove for the rear end are shown. A cross section of (second ink receiving portion) 31B is shown. As shown in FIG. 4, the front end ink discarding groove 31 </ b> A extends in the X direction adjacent to the downstream side of the sheet support portion 14, and the rear end ink discard groove 31 </ b> B is formed on the sheet support portion 14. It is elongated in the X direction adjacent to the upstream side.

  On the other hand, in order to surely perform borderless printing on the left and right ends (sheet side ends) of the sheet 2, when the print head 3 ejects ink while scanning in the X direction, it is located outside the left and right ends of the sheet 2. It is necessary to discharge the ink up to. In addition, even when the sheet width of the sheet 2 to be used is changed, the platen 9 has left and right edges that match the width of each sheet so that ink ejected outside the left and right edges of the sheet 2 can be received. An ink discarding groove (third ink receiving portion) 34 is provided (see FIG. 3).

  As the size of the sheet 2 on which borderless printing is performed, a standard size sheet 2 such as L size, 2L size, postcard, A4, letter, A3, legal, A2 is mainly used. Therefore, a plurality of ink discarding grooves 34 are arranged at the left and right sheet edge positions of each sheet 2 in accordance with these sheet sizes. As described above, the front-side ink discarding groove 31A, the rear-end ink discarding groove 31B, and the right-and-left-end ink discarding grooves 34 are formed on the surface of the platen 9 so as to form a lattice pattern. Has been.

  Assuming that borderless printing is performed on the four sides of the cut sheet in this way, the sheet support portion 14 of the platen 9 has the leading and trailing edge ink discarding grooves 31A and 31B, and the left and right edge ink discarding grooves of the sheet. 34, and is in an isolated form. Further, in each of the ink discarding grooves 31A, 31B, and 34, in order to reduce the occurrence of mist due to the rebound at the time of landing of the ink and the leakage of the discarded ink, as shown in FIG. 5 and FIG. An absorber 35 is disposed. The ink absorber 35 is preferably composed of a single sponge-like sheet such as urethane foam. Further, the upper surface of the ink absorber 35 is locked by a plurality of locking claws 38 (see FIG. 7), and the ink absorber 35 is prevented from falling off the platen 9.

  Further, as shown in FIG. 5, an outer peripheral wall 20 that protrudes downward is formed on the surface of the platen 9 opposite to the surface facing the print head 3. Further, the space formed by the outer peripheral wall 20 is divided into a plurality of spaces 22 by a dividing wall 20a as shown in FIGS. A plurality of spaces 22 formed by the partition wall 20 a and the outer peripheral wall 20 are negative pressure chambers to which a negative pressure is applied by the negative pressure generating means 19. Each negative pressure chamber 22 corresponds to the suction recess 17 of each sheet support portion 14. When negative pressure is applied to the negative pressure chamber 22 by the negative pressure generating means 19, air is sucked from the suction hole 18 of the suction recess 17, and the sheet 2 is sucked to the sheet support surface 13 of the sheet support portion 14.

  On the other hand, slit holes 423 and 424 for sucking and collecting ink mist generated when ink is ejected into the ink receiving groove are formed in the side wall portion of the sheet support portion 14 of the platen 9. 3 and 5 show the positions where the slit holes 423 and 424 are formed. As shown in the drawing, the first slit hole 423 is formed in the downstream side wall portion 140 </ b> A substantially parallel to the sheet width direction (X direction) that is a direction intersecting the sheet conveying direction (Y direction) among the sheet support portions 14. Is formed. Further, a second slit hole 424 is formed in the side wall portion 140D of the sheet support portion 14 that is disposed substantially parallel to the sheet conveyance direction. The first slit hole 423 and the second slit hole 424 communicate with the negative pressure chamber 22, and air is sucked from the slit holes 423 and 424 together with the suction hole 18 by driving the negative pressure generating means 19. The

  In the printing apparatus, it is desirable to perform printing with the sheet 2 covering the sheet support portion 14. That is, when suction is performed from the suction hole 18 in a state where the sheet support portion 14 is covered with the sheet, a negative pressure is generated in the space formed by the suction recess 17 and the sheet 2 covering the suction recess 17, and the negative pressure is generated. Thus, the sheet 2 is attracted to the sheet support surface 13 of the sheet support portion 14. For this reason, it is possible to suppress the occurrence of sheet floating and bending such as cockling and curling during printing. As a result, the distance between the ejection port surface 3a of the print head 3 and the sheet 2 (inter-sheet distance) is maintained at an appropriate preset distance, and the deviation of the landing position of the ink ejected from the print head 3 is reduced. As a result, high-quality image formation is possible.

  Further, in borderless printing, the ink ejected to the outside (downstream side) from the front end of the sheet 2 lands on the ink absorber 35 located in the front end side ink discarding groove 31A. At this time, a mist-like minute ink droplet (ink mist) is generated at the time of impact upon landing on the ink absorber 35 or at the time of ink ejection, and this floats in the air. When the ink mist is drawn toward the suction recess 17 by the negative pressure of the suction hole 18 and passes through a minute gap between the sheet support portion 14 and the sheet 2, a part of the mist contacts the back surface of the sheet 2. May adhere and stain the back surface of the sheet 2. However, in this embodiment, since the first slit hole 423 is formed in the side wall portion 140A on the downstream side of the sheet support portion 14, the ink mist is drawn in FIG. As indicated by an arrow F, suction is performed by the first slit hole 423. As a result, even when borderless printing is performed, the ink mist that contacts the back surface of the sheet 2 can be greatly reduced, and the stain due to the ink mist on the back surface of the sheet 2 can be greatly reduced. In the present embodiment, the second slit hole 423 is formed in the side wall portion 140A on the upstream side of the sheet support portion 14, but a similar slit hole may be formed in the side wall portion 140B on the downstream side of the sheet support portion 14. In this case, it is possible to reduce the adhesion of ink mist to the rear end 2b of the sheet 2.

  The processing of the mist generated when printing the leading edge 2a and the trailing edge 2b of the sheet 2 in borderless printing has been described above. Next, it occurs when printing on the left and right end portions of the sheet 2 in borderless printing. The ink mist process will be described.

  FIG. 5 is an enlarged plan view showing a part of the platen 9, and shows the positional relationship between the sheet support portion 14 of the platen 9 and the size of the sheet 2. FIG. 6 is a longitudinal front view of the platen, which shows a path through which ink mist generated when the left and right ends 2a and 2b of the sheet 2 are printed is sucked.

  The arrangement of the sheet support portion 14 in the sheet width direction (X direction) and the position of the ink discarding groove are the sheet size (for example, L plate, KG, 2L, A4, letter, A3, etc.) and print capable of borderless printing. It is determined according to location standards. In this embodiment, a so-called center reference sheet supply is adopted in which the reference of the print position is set at the center of the sheet width. FIG. 5 shows the positional relationship between the end portions of the A4 size sheet 2 and the A3 size sheet 2 and the support portions 14 of the platen. In the figure, P0 indicates the reference (center reference) of the printing position of the platen 9 and the sheet 2, P1 indicates the end position of the A4 size sheet 2, and P2 indicates the end position of the A3 size sheet 2. Yes. Note that instead of the center reference, sheets having various sheet widths may be used as a one-side reference that aligns the left and right reference positions.

  Further, of the side wall portions of the sheet support portion 14, the left and right side wall portions 140 </ b> C and 140 </ b> D formed in a direction parallel to the sheet conveyance direction are located at positions close to the left and right end portions 2 c and 2 d of the sheet 2. A first slit hole is formed in the side wall portion. Since the center reference is adopted as described above, the second slit hole 424 is formed in the right side wall part 140D in the sheet support part 14 located on the right side of the reference P as shown in FIGS. ing. Moreover, in the support part 14 located in the left side from the reference | standard P, the 2nd slit hole 424 is formed in the left side wall part 140C (refer FIG. 6). Similar to the first slit hole, the second slit hole 424 communicates with the negative pressure chamber 22 formed corresponding to the sheet support portion 14, and the negative pressure generating means 19 allows the second slit hole 424 to communicate with the negative pressure chamber 22. The air outside the sheet support portion 14 can be sucked into the negative pressure chamber 22 by the applied negative pressure.

  With the above configuration, the ink mist generated by the borderless printing on the left and right end portions 2c and 2d of the sheet 2 is located near the left and right end portions 2a and 2b of the sheet 2 as shown by an arrow G in FIG. The second slit hole 424 is quickly sucked and sent to the negative pressure chamber 22. Thereby, the ink mist which contacts the back surface of the sheet 2 is reduced, and the stain on the back surface of the sheet 2 due to the ink mist is reduced. In addition, since the time during which the ink mist is floating in the printing apparatus 1 can be reduced, contamination in the printing apparatus 1 can also be suppressed.

  Of the left and right side wall portions 140C and 140D of the sheet support portion 14, the slit hole 424 is formed in the side wall portion closer to the left and right end portions 2c and 2d of the sheet 2, but the other side wall portion is also formed. A slit hole may be formed. In the case where the one-side reference is used instead of the center reference, a slit hole may be formed in at least one of the left and right side wall portions of the sheet support portion that is farther from the reference.

  Here, the configuration of the first slit hole 423 and the second slit hole 424 will be described in more detail. FIG. 7 is a longitudinal side view of the sheet support portion 14 and shows the configuration of the second slit hole 424 formed in the sheet support portion 14. In the following description, the second slit hole 424 formed in the left side wall portion 140C of the sheet support portion 14 will be described based on FIG. However, the second slit hole 424 formed in the right side wall part 140D and the slit hole 423 formed in the upstream side wall part 140A also have the same configuration, and here, the overlapping description of the slit hole 424 is provided. Is omitted. The platen 9 has a substantially horizontal step 141 formed on the left side wall portion 140C of the sheet support portion 14 and a side portion 142 that rises upward from the step 141. A second slit hole 424 is formed between the step portion 141 and the side surface portion 142 along the sheet conveying direction (Y direction). Further, the side wall portion 140C and the side surface portion 142 of the seat support portion 14 are formed so as to extend in a substantially vertical direction.

  Thus, the slit hole 424 is formed by forming the step part 141 in the side wall part 140C extending in the substantially vertical direction. On the other hand, in order to form a slit hole, it is also possible to make the side wall part into the shape which inclined and to form a slit hole in this inclined side wall part. However, in this case, the distance in the sheet width direction increases due to the inclination, and in order to obtain the same volume as that of the present embodiment in the ink receiving groove, it is necessary to widen the space between the adjacent sheet support portions 14. There is a tendency for the sheet to drop between adjacent sheet support portions. As a result, the distance between the print head and the sheet (the distance between the sheets) is not uniform, and the landing position may be shifted in the ink ejected from the print head, which may impair the image quality. In addition, depending on how the sheet falls, the sheet may come into contact with the ink absorber 35 to contaminate the sheet. Furthermore, the shape of the ink absorber 35 must be formed with a non-uniform thickness along with the inclination of the side wall portion forming the slit hole, which makes it difficult to manufacture the ink absorber. On the other hand, according to the present embodiment, since the side wall portion 140C is formed substantially vertically, it is possible to keep the interval between the adjacent sheet support portions 14 to the minimum necessary, and in the ink discarding groove. It is possible to avoid a drop of the sheet and adhesion of waste ink to the back surface of the sheet. Furthermore, since the ink absorber has only to be formed to a uniform thickness, the manufacture becomes easy.

  FIG. 8 is a longitudinal side view showing a part of the platen 9 shown in FIG. 4, in which the positional relationship between the first slit hole 423 and the ink absorber 35 is shown. In the downstream ink receiving groove 31 </ b> A, the opening of the first slit hole 423 is provided at a position higher than the ink absorber 35 by Z <b> 1 in the vertical direction (position close to the print head 3). With such a positional relationship, even when the ink absorber 35 is filled with waste ink, the waste ink passes through the side wall portion 140A and the step portion 141 adjacent to the leading-end ink discarding groove 31A. It is possible to avoid flowing into one slit hole 423. Therefore, clogging of the slit hole 423 and deterioration of suction performance due to the flow of waste ink can be suppressed. Similarly to the positional relationship between the ink absorber 35 and the opening of the first slit hole 423 in the vertical direction, the positions of the slit holes 424 and the ink absorber 35 formed in the left and right side wall portions 140C and 140D. Relationships are also defined.

  Note that when the positional relationship in the vertical direction between the position of the opening of the first slit hole 423 and the ink absorber 35 is reversed, the waste ink deposited on the ink absorber 35 is removed from the first slit hole 423. It becomes easy to flow into. When waste ink flows into the first slit hole 423, the slit hole may be blocked due to thickening and solidification of the ink. When the slit hole is blocked, the floating ink is not sucked, and the floating ink may be attracted to the suction hole 18 and the back surface of the sheet may be stained.

  Further, when the distance between the print head 3 and the ink absorber 35 is shortened, the ink ejected to the ink absorber 35 rebounds and can land on the back surface of the sheet 2 before being sucked into the slit holes 423 and 424. There is sex. Therefore, the ink absorber 35 is set below the slit holes 423 and 424 so as to maintain a certain distance from the print head 3 as in the present embodiment, so that the above problems are solved. Is done. Further, when the ink absorber 35 is incorporated in the ink discarding groove, the ink absorber 35 can be incorporated while visually comparing the position with the stepped portion 141. Therefore, the presence of the stepped portion 141 is effective in preventing erroneous assembly.

  The platen 9 is manufactured as one part by a resin mold. The plurality of sheet support portions 14, the upstream sheet support portion 32, the downstream sheet support portion 33, the plurality of negative pressure chambers 22, and the ink receiving portions (first to third ink receiving portions) all constitute the platen 9. It is formed in one resin mold part. This simplifies the manufacturing of the printing apparatus and improves the relative positional accuracy of the functional units.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. In the first embodiment, the step portion 141 is formed on the side wall portion 140D formed in the vertical direction of the sheet support portion 14, and the side surface portion 142 that rises from the step portion 141 in the substantially vertical direction is formed. A slit hole for absorbing ink was formed between the side surface portions 142. On the other hand, in the second embodiment, the first slit hole 425 that passes through the side wall portions 140A and 140D formed in the substantially vertical direction of the sheet support portion 14 and communicates with the negative pressure chamber 22, the second The slit hole 426 is formed (see FIG. 10).

  FIG. 9 shows a case where the first slit hole 425 is formed in the upstream side wall portion 140A, and the second slit hole 426 is formed in the right side wall portion 140D. However, the other side wall portions 140B and 140C have the first slit hole 425 formed therein. It is also possible to form the first and second slit holes 425 and 426. Further, the openings of the slit holes 425 and 426 are set at a position higher than the ink absorber 35 (position close to the print head) to avoid waste ink flowing into the slit holes 425 (see FIG. 10). Other configurations are the same as those in the first embodiment.

  As described above, in the second embodiment, the step portion and the side surface portion are not formed on the side wall portion of the sheet support portion 14. For this reason, compared with the first embodiment, the distance between the adjacent sheet support portions 14 can be reduced by the distance T, and the area of the sheet support surface 13 can be increased. Thereby, the support of the sheet | seat 2 more stable is attained.

  As described in the above embodiments, in order to suck ink mist, it is effective to provide a slit hole in any side wall portion formed in the sheet support portion 14. However, it may be more effective to prevent the ink from adhering to the back surface of the sheet if the slit hole is not formed in the side wall portion formed on the upstream side in the transport direction. That is, the upstream side wall portion may be an inclined surface that is inclined upward from downstream to upstream, and this inclined surface may function as a guide surface for smoothly moving the front end portion of the seat to the seat support surface. . In this case, if a slit hole is formed in the side wall portion on the upstream side, this slit hole may hinder smooth movement of the sheet. In addition, when a slit hole is formed in the upstream side wall, ink mist may adhere to the upstream side wall when sucked into the slit hole, and the back surface of the sheet guided to the side wall may be stained with ink. is there. For these reasons, it may be desirable not to form slit holes in the upstream side wall.

  According to the embodiment that has been described above, it is possible to perform printing without a four-sided border on a cut sheet. In addition, it is possible to reliably perform borderless printing, and it is possible to suppress the back surface of the sheet from being stained with ink mist generated when ink is ejected to the outside of the sheet edge.

2 Sheet 3 Print head 9 Platen 14 Support part 17 Adsorption recess (suction part)
18 Suction hole 22 Negative pressure chamber 31A Front end ink discarding groove 31B Rear end ink discarding groove 34 Left and right end ink discarding groove 35 Ink absorber 140B Upstream side wall 140A Downstream side wall 140C Left side wall Part 140D Right side wall part 141 Step part 142 Side part 423 First slit hole 424 Second slit hole

Claims (11)

A printing apparatus comprising: a print head that ejects ink; and a platen that supports a sheet facing the print head,
The platen is
A support for supporting the sheet;
A suction hole that is provided in the support part and that adsorbs a sheet to the support part;
An ink receiving portion that is provided on at least one of the upstream side and the downstream side of the support portion in the sheet conveyance direction, and that receives ink ejected from the print head on the outside of the sheet supported by the support portion;
Have
The printing apparatus according to claim 1, wherein a slit hole for sucking air is formed in a part of a side wall part adjacent to the ink receiving part in the support part separately from the suction hole.   The plurality of the support portions are arranged side by side in the sheet width direction intersecting the transport direction, and the slit hole is formed in a side wall of each of the support portions. Printing device.   The printing apparatus according to claim 1, wherein the slit hole extending in the sheet width direction is formed in at least one of the upstream side wall portion and the downstream side wall portion of the support portion. .   The printing apparatus according to claim 3, wherein the slit hole is formed only in the downstream side wall portion of the upstream side wall portion and the downstream side wall portion.   The support portion has a step portion formed on a side wall portion adjacent to the ink receiving portion, and the slit hole is formed between the step portion and a side portion rising from the step portion. The printing apparatus according to any one of claims 1 to 4.   The printing apparatus according to claim 1, wherein the slit hole communicates with a negative pressure chamber that applies a negative pressure to the suction hole. In the ink receiving portion, an absorber having an ink receiving surface is disposed at a position lower than a position where the support portion supports the sheet,
The printing apparatus according to claim 1, wherein the slit hole is formed at a position higher than the ink receiving surface. A printing apparatus comprising: a print head that ejects ink; and a platen that supports a sheet facing the print head,
The platen is
A support capable of supporting the sheet;
A suction hole that is provided in the support part and that adsorbs a sheet to the support part;
An ink receiver that receives ink ejected from the print head on the outside of the sheet supported by the support;
Have
The support portion is formed with a step portion on a side wall portion adjacent to the ink receiving portion, and a slit hole for sucking air is provided separately from the suction hole between the step portion and a side portion rising from the step portion. A printing apparatus characterized by being formed.   9. The printing apparatus according to claim 1, wherein the support portion and the ink receiving portion are formed in a single resin mold part that constitutes the platen. 10. A platen disposed opposite to a print head that ejects ink,
A support capable of supporting the sheet;
A suction hole that is provided in the support part and that adsorbs a sheet to the support part;
An ink receiving portion that is provided on at least one of the upstream side and the downstream side of the support portion in the sheet conveyance direction, and that receives ink ejected from the print head on the outside of the sheet supported by the support portion;
Have
The platen according to claim 1, wherein a slit hole for sucking air is formed in a part of a side wall adjacent to the ink receiving part in the support part separately from the suction hole. A platen disposed opposite to a print head that ejects ink,
A support for supporting the sheet;
A suction hole that is provided in the support part and that adsorbs a sheet to the support part;
An ink receiver that receives ink ejected from the print head on the outside of the sheet supported by the support;
Have
The support portion is formed with a step portion on a side wall portion adjacent to the ink receiving portion, and a slit hole for sucking air is provided separately from the suction hole between the step portion and a side portion rising from the step portion. A platen characterized by being formed.