JP4893658B2 - Platen and image recording apparatus - Google Patents

Description

  The present invention relates to a platen used for image recording in an ink jet recording system and an image recording apparatus equipped with the platen.

  2. Description of the Related Art Conventionally, in a serial type ink jet recording type printer, a carriage capable of reciprocating in a predetermined direction (main scanning direction), a recording head mounted on the carriage and capable of ejecting ink from a nozzle surface (ink ejection surface), It has. A platen is disposed at a position facing the recording head with a predetermined gap, and the recording paper is intermittently conveyed in a direction orthogonal to the predetermined direction while being supported by the platen, and the recording head faces the recording head. An image is recorded on the recording paper by ejecting ink droplets from the recording head onto the surface of the paper.

  By the way, so-called borderless image recording, in which an image is recorded on one side of a recording sheet without a margin, is known. When this borderless image recording is executed, generally, when the leading edge of the recording paper comes within the ink discharge range (recording area) by the recording head, the recording head applies ink to an area slightly larger than the size of the recording paper. Discharge. The same applies to the side edge of the recording paper, and also to the rear edge of the recording paper. Then, ink droplets that do not land on the recording paper land (attach) on the platen. Then, when the recording paper on which an image is recorded next is supported by the platen and conveyed, the back surface of the paper (the surface opposite to the surface on which the image is recorded) is stained with ink adhering to the platen. There was a problem that.

  In order to solve this problem, in Patent Document 1, an upstream side wall that stands upright on the upstream side in the recording sheet conveyance direction outside the image recording area by the recording head and a recording sheet that is also outside the image recording area. A downstream side wall standing upright on the downstream side in the transport direction is formed to extend along the main scanning direction. A platen that opens upward is disposed between the upstream side wall and the downstream side wall. In addition, a technique has been proposed in which ribs protrude from the upper ends of the upstream side wall and the downstream side wall, and an ink absorber is disposed in the opening of the platen.

On the other hand, in Patent Document 2, a paper feed roller is arranged on the upstream side in the recording paper conveyance direction outside the image recording area (printing area) by the recording head, and the recording paper conveyance is also outside the printing area. A discharge roller is disposed downstream in the direction. A casing (printing area) in which an ink absorber is arranged at the lower part is arranged in the printing area in the meantime. A plurality of fin-shaped leading end guide members whose guide surfaces (upper surfaces) are separated from the sheet are fixed to the upper portion of the casing. And the said front-end | tip guidance guide member is what is formed in the inclined form so that the clearance gap between the guide surface (upper surface) and the paper to pass may become narrow toward the conveyance downstream. Further, the guide surface located at least on the outer side in the sheet width direction of the leading-end guide member is disposed so as to be inclined outward with respect to the sheet conveyance direction.
Japanese Patent Laid-Open No. 2000-118058 (see FIGS. 3 to 5) Japanese Patent No. 2945781 (see FIGS. 1 to 3)

  However, according to the structure of Patent Document 1 described above, a problem occurs in the following cases when the distance between the upstream side wall and the downstream side wall of the platen in the transport direction is wide. That is, when the leading edge of the paper is positioned in the opening beyond the rib on the upstream side wall or when the trailing edge of the paper is positioned in the opening after passing through the rib on the upstream side wall, that is, the leading edge or the trailing edge of the paper. This is a problem when the end edge is cantilevered by the rib on the upstream side wall or the downstream side wall. When supported in this way, paper with a low stiffness or paper with its leading edge or trailing edge curled downwards will hang down at the leading edge or trailing edge of the ink absorber in the opening. There is a problem that the leading edge and the trailing edge of the paper are easily contacted with ink and become dirty with ink.

  On the other hand, according to the structure of Patent Document 2, the downstream end portions of the plurality of fin-shaped tip guide guide members are connected (connected) to the downstream side wall of the casing. Then, when the ink ejected in the printing area adheres to the guide surface of the tip guide member, the ink rises (diffuses) along the guide surface that is inclined upward toward the downstream side due to the capillary action of the ink. Finally, there is a possibility that the top of the highest downstream side wall gets wet with ink. As a result, when the passing paper contacts the top surface of the highest downstream side wall, there is a problem that the back surface of the paper is stained with ink over a wide range. This phenomenon can also occur on the upstream side wall of the casing.

  Further, according to the structure of Patent Document 2, the guide surface located at least outside in the paper width direction of the leading-end guide member is arranged so as to be inclined outward with respect to the paper transport direction. In such cases, problems occur. In this case, that is, a middle part in the paper transport direction is supported by the pair of upstream transport rollers, but a downstream end in the paper transport direction (hereinafter referred to as the leading edge) is supported. There is no state (supported like a cantilever beam by a pair of conveying rollers), in particular, a state where the tip end portion is curled downward. In this state, the portion where the ink ejected from the nozzle of the recording head adheres to the guide surface of the leading guide member located at least on the outer side in the paper width direction is the leading edge of the next (following) paper. When the paper passes, as the paper advances (moves downstream), the portion where the guide surface of the leading guide member contacts the front edge of the paper moves so as to be shifted to the outside of the paper. As a result, the ink adhering to the back surface of the leading edge of the paper spreads in the width direction of the paper, and there is a problem that the contamination range by the ink is widened.

  Note that the height dimension (gap space) from the upper surface of the ink absorber to the upper end surface of the rib is increased in order to avoid contact between the upper surface of the ink absorber disposed in the image recording area (printing area) and the paper. When set, the following problems occur. That is, ink droplets accidentally ejected from the recording head without the presence of paper during image recording work, ink droplets ejected from the recording head but not landed on the recording paper, etc. land (attach) to the ink absorber. It becomes an ink mist without drifting and drifts in the gap space. Such ink mist adheres to the succeeding recording paper and ribs, thereby contaminating the front and back surfaces of the recording paper. As a result, there is a problem that image quality deteriorates.

  The present invention has been made in order to solve the above-described problems, and is capable of recording a borderless image without contaminating the back surface of the recording medium and having a simple configuration and an image recording including the platen. The object is to provide an apparatus.

  In order to achieve the above object, the invention according to claim 1 has a recording area that is disposed opposite to a recording head that includes nozzles capable of ejecting ink droplets, and on which ink ejected from the nozzles can land, A platen that supports a recording medium that can be transported along a predetermined direction, wherein a plurality of upstream ribs that support the recording medium are provided upstream of the recording area in the transport direction, and the transport direction Downstream of the recording area is provided with a downstream support part for supporting the recording medium, and at least a front end part and a rear end part in the transport direction of the recording medium can be supported in the recording area, respectively. One in-region support rib is provided so as to extend along the transport direction, and the at least one in-region support rib has a height at the upper end surface of the upstream rib and the downstream support. Lower than the height of the upper end surface of the, it is what is formed so as to overlap with at least one of the upstream ribs or the downstream support portion when and projected view the platen from the side.

  According to a second aspect of the present invention, in the platen according to the first aspect, the in-region support ribs are formed so as to protrude from the surface of the bottom plate of the platen.

According to a third aspect of the present invention, in the platen according to the first or second aspect, the upper end surface of the in- region support rib is a nozzle of the recording head from the downstream end to the upstream end in the transport direction. It is formed so as to be parallel to the surface.

  According to a fourth aspect of the present invention, in the platen according to the first or second aspect, the height of the support ribs in the region is low at a midway portion in the transport direction in the recording region, and the transport is performed. It has a downstream side inclined surface and an upstream side inclined surface so that the height in the downstream end part and upstream end part of a direction may become high.

  According to a fifth aspect of the present invention, in the platen according to the fourth aspect, the midway provided with a horizontal plane higher than the surface of the bottom plate between the downstream inclined surface and the upstream inclined surface of the in-region support rib. It is connected to the part.

  According to a sixth aspect of the present invention, in the platen according to any of the first to fifth aspects, the upstream end in the transport direction of at least one of the in-region support ribs is the upstream side. It is connected to the rib.

  According to a seventh aspect of the present invention, in the platen according to any one of the first to sixth aspects, at least one of the in-region support ribs is in the transport direction with respect to the upstream rib. It is arranged at a position appropriately deviated in the orthogonal direction, and the height of the upstream end of the at least one in-region support rib is set lower than the height of the downstream end of the upstream rib. is there.

  According to an eighth aspect of the present invention, in the platen according to any one of the first to seventh aspects, the upstream end of the downstream support portion has a top that is higher than the downstream end of the in-region support rib. The top is formed so as to extend in a direction along the surface of the platen and in a direction perpendicular to the transport direction.

  A ninth aspect of the present invention is the platen according to the eighth aspect, wherein a concave portion is formed in the top portion at a position corresponding to the in-region support rib in the transport direction.

  According to a tenth aspect of the present invention, in the platen according to any one of the first to ninth aspects, a roller body that conveys a recording medium is provided on the downstream side in the conveyance direction from the downstream support portion. The roller body is disposed at a position appropriately deviated from a position corresponding to the in-region support rib in the transport direction in a direction along the surface of the platen and in a direction orthogonal to the transport direction. .

  According to an eleventh aspect of the present invention, in the platen according to any one of the first to tenth aspects, an ink absorber that absorbs excess ink adhering to the recording area is disposed below the downstream support portion. It is what.

  According to a twelfth aspect of the present invention, in the platen according to the eleventh aspect, an ink channel groove extending along the transport direction is formed in the bottom plate between the support ribs in the recording area. The ink flow path groove is provided so as to communicate with an arrangement position of the ink absorber that absorbs at least excess ink.

  According to a thirteenth aspect of the present invention, in the platen according to any one of the first to twelfth aspects, a center line in the width direction perpendicular to the conveyance direction of the recording medium is perpendicular to the conveyance direction of the platen. When the recording medium is transported so as to pass through the predetermined position, the predetermined position among the plurality of in-region support ribs arranged at appropriate intervals in a direction orthogonal to the transport direction in the platen The height of one in-region support rib arranged at a position corresponding to is set higher than the height of other in-region support ribs.

  According to a fourteenth aspect of the present invention, there is provided a platen according to any one of the first to thirteenth aspects, a carriage that can reciprocate along a predetermined direction within the main body, and a carriage mounted on the carriage. A recording head capable of recording an image on a recording medium that can be transported on the platen in a direction orthogonal to the moving direction of the carriage by selectively discharging, and the nozzle surface of the platen and the recording head Are arranged opposite to each other with a predetermined gap.

  According to the first aspect of the present invention, the recording head is disposed so as to face a recording head including nozzles capable of ejecting ink droplets, and the ink ejected from the nozzles can be landed and can be transported along a predetermined direction. A platen for supporting a recording medium, wherein a plurality of upstream ribs for supporting the recording medium are provided upstream of the recording area in the transport direction, and downstream of the recording area in the transport direction. A downstream support portion for supporting the recording medium is provided, and at least one in-region support rib capable of supporting each of the front end portion and the rear end portion in the transport direction of the recording medium is provided in the recording region. The at least one in-region support rib is provided so as to extend along the conveying direction, and the height thereof is lower than the height of the upper end surface of the upstream rib and the upper end surface of the downstream support portion. And among the upstream ribs or the downstream support portion said platen from the side when projected view in which are formed so as to overlap with at least one.

  Therefore, when performing edgeless image recording, the front end portion (front end edge) and the rear end portion (rear end edge) of the recording medium are supported in a cantilevered manner and hang down and are arranged in the recording area. The front end portion (leading edge) and the rear end portion (rear end edge) of the recording medium can be supported by the supporting ribs in the region, and the back surface of the recording medium can be prevented from being stained with excess ink.

  The at least one in-region support rib is lower in height than the upper end surface of the upstream rib and the upper end surface of the downstream support portion, and the upstream side when the platen is viewed from the side. Since it is formed so as to overlap with at least one of the side rib or the downstream support portion, the front end portion (front end edge) and the rear end portion (rear end edge) of the recording medium are located at the overlapping portion. When passing, the back surface of the recording medium does not come into contact with the ink accumulated in the overlapped area, so that the ink is not stained.

  According to the second aspect of the present invention, since the in-region support ribs are formed so as to protrude from the surface of the bottom plate of the platen, the front end portion (front end edge) and the rear end portion (rear end) of the recording medium are recorded. Even if the edge is supported like a cantilever and hangs down, it can be supported by the in-region support rib, and the front end of the recording medium (on the surface of the platen bottom plate other than the in-region support rib which is the ink discarding portion) The leading edge) and the trailing edge (rear edge) are not touched, and the back surface of the recording medium can be prevented from being soiled by the discarded (surplus) ink.

According to a third aspect of the present invention, the upper end surface of the in- region support rib is formed so that the downstream end in the transport direction to the upstream end is parallel to the nozzle surface of the recording head. Therefore, even if the front end portion (leading edge) and the rear end portion (rear end edge) of the recording medium are supported in a cantilever manner and hang down, the back surface of the recording medium is discarded (surplus). Can be prevented from being stained with ink.

  According to the invention of claim 4, the height of the in-region support ribs is low in the middle portion in the transport direction in the recording region, and the downstream end and the upstream end in the transport direction. It has a downstream side inclined surface and an upstream side inclined surface so that the height at the height is high.

  Accordingly, when the front end portion (front end edge) of the recording medium is supported in a cantilever manner and hangs down, the recording medium is supported by the high-level inclined surface at the downstream end portion in the transport direction, and similarly the recording medium When the rear end portion (rear end edge) is supported in a cantilever manner and hangs down, it can be supported by an upstream inclined surface having a high height at the upstream end portion in the transport direction. The leading edge) and the trailing edge (rear edge) are less likely to drop, and the deterioration of image recording quality can be reduced.

  According to the fifth aspect of the present invention, the intermediate portion in the transport direction has a higher horizontal surface than the surface of the bottom plate, and the downstream inclined surface and the upstream inclined surface are connected to the intermediate portion. The back surface of the recording medium is also supported so as to be lifted from the bottom plate of the platen, and is not stained with excess ink.

  When the upstream end in the transport direction of at least one of the in-region support ribs is connected to the upstream rib as in the invention of claim 6, the upstream rib Thus, the drop when the rear end of the recording medium is transferred from the support rib to the in-region support rib can be remarkably reduced, which can further contribute to maintaining the quality of image recording.

  As in the invention of claim 7, at least one in-region support rib among the in-region support ribs is disposed at a position appropriately deviated in a direction orthogonal to the transport direction with respect to the upstream rib, If the height of the upstream end of one in-region support rib is set lower than the height of the downstream end of the upstream rib, a recording medium having a small size is recorded by the recording head in the borderless recording region. When an edgeless image is recorded, ink ejected to a position protruding from the rear edge of the recording medium adheres to the upper end surface (guide surface) of the in-region support rib, and the upper end surface of the in-region support rib ( It can be set so as to accumulate at the upstream end of each region supporting rib through the guide surface.

  Then, the front half of the recording medium to be recorded and transported without border is one-side supported by the downstream support portion, and the rear edge of the recording medium is placed on the downstream end in the transport direction of the upstream rib. Sometimes, the height of the portion is high, and the upstream end of the upstream rib in the transport direction is offset from the upstream end of the support rib in each region, and is not connected to the transport direction. The ink collected at the end does not touch the trailing edge of the recording medium. Further, even when the trailing edge of the recording medium changes to the support rib side in each region, the accumulated ink is already positioned downstream in the transport direction from the ink reservoir, so that the accumulated ink is behind the recording medium. The trailing edge of the recording medium is not soiled without touching the edge, and the ink does not spread downstream of the upper end surface (guide surface) of the in-region support rib, and the subsequent recording medium is soiled. There is nothing.

  According to the invention of claim 8, the upstream end portion of the downstream support portion is formed with a top portion that is higher than the downstream end portion of the in-region support rib, and the top portion is along the surface of the platen. And extending in a direction perpendicular to the transport direction. Therefore, the entire width of the recording medium on which an image is recorded can be supported on the top.

  According to invention of Claim 9, the recessed part is formed in the position corresponded to the said area | region support rib in the said conveyance direction among the said top parts. With this configuration, the leading end (leading edge) of the recording medium to be transported rubs against the upper end surface (guide surface) of the in-region supporting rib, and the ink adheres to the leading end of the recording medium. Even so, since the ink adhering portion passes within the width dimension of the concave portion, the ink adhering portion can be prevented from spreading in the width direction of the recording medium on the back surface of the recording medium. In addition, since ink does not transfer from the ink adhering portion of the leading end portion (leading edge) of the preceding recording medium to the top portion, even if the back surface of the succeeding recording medium contacts (rubs) the top portion, It is possible to reliably prevent the back surface of the subsequent recording medium from being stained with ink.

  According to the invention of claim 10, the roller body provided on the downstream side in the transport direction with respect to the downstream side support portion is in a direction along the surface of the platen from the position corresponding to the in-region support rib in the transport direction and in the transport direction. If it is arranged so as to be appropriately deviated in the direction orthogonal to the direction (Y-axis direction), the back surface portion of the recording medium to which the ink has adhered by rubbing against the upper end surface (guide surface) of the in-region support is directly Since the roller body is not touched, the ink stains do not diffuse and the back surface of the subsequent recording medium does not get dirty.

  According to the eleventh aspect of the invention, an ink absorber that absorbs excess ink adhering to the recording area is disposed below the downstream support portion. Since the recording medium passing therethrough does not come into direct contact with the ink absorber, it is not contaminated with discarded (surplus) ink.

  According to a twelfth aspect of the present invention, an ink channel groove extending along the transport direction is formed in the bottom plate between the support ribs in the recording region, and the ink channel groove is at least surplus. The ink absorber is provided so as to communicate with an arrangement portion of an ink absorber that absorbs ink. Accordingly, the ink discarded in the bordered recording area and the borderless recording area is guided to the ink absorber arrangement portion via the ink flow path groove, so that the back surface of the recording medium is prevented from being stained with ink. Increases effectiveness.

  According to a thirteenth aspect of the present invention, the recording medium is arranged such that a center line in the width direction orthogonal to the conveyance direction of the recording medium passes through a predetermined position in the direction orthogonal to the conveyance direction of the platen. When transported, one in-region support rib arranged at a position corresponding to the predetermined position among the plurality of in-region support ribs arranged at appropriate intervals in a direction orthogonal to the transport direction in the platen Is set higher than the height of the supporting ribs in other regions.

  Therefore, even if the leading edge of the recording medium wet due to the ejected ink may curl downward due to the borderless image recording, the leading edge of the recording medium is more than the above-mentioned other area support ribs. It moves downstream while contacting the upper end surface (guide surface) of at least one tall long-area support rib. For example, the recording medium is transported so that the center line in the width direction orthogonal to the transport direction in the recording medium passes through a predetermined position in the direction orthogonal to the transport direction in the platen (for example, the central portion in the longitudinal direction of the platen). The height of one in-region support rib arranged at a position corresponding to a predetermined position among the plurality of in-region support ribs arranged at appropriate intervals in the direction orthogonal to the conveying direction in the platen, If the height of the supporting ribs in the other area is set higher than the height of the supporting ribs in the other area, the central part in the width direction of the small-sized recording medium first moves to the top part. The ink flow path is not touched.

  According to a fourteenth aspect of the present invention, the platen according to any one of the first to thirteenth aspects, a carriage that can reciprocate in a predetermined direction within the main body, and a carriage that is mounted on the carriage and ejects ink droplets from the nozzles. A recording head capable of recording an image on a recording medium that can be transported on the platen in a direction orthogonal to the moving direction of the carriage by selectively discharging, and the nozzle surface of the platen and the recording head Are opposed to each other with a predetermined gap, so that the recording medium on which the image is recorded can be recorded without being contaminated, and the platen can be recorded without borders and has a simple structure. An image recording apparatus can be provided.

  An exemplary embodiment of the present invention will be described with reference to the drawings. 1 is a perspective view seen from the front of a multifunction machine applied to the present embodiment, FIG. 2 is a plan view of the recording unit, FIG. 3 is a schematic sectional view of the recording unit, and FIG. 4 is a guide member downstream from the recording unit. FIG. 5 is a plan view of a state where the downstream guide member 23 is removed from the recording unit, FIG. 6 is a perspective view of the platen of the first embodiment, and FIG. FIG. 8 is an enlarged sectional view taken along the line VIII-VIII in FIG. 7, FIG. 9 is an enlarged perspective view partially cut away of the in-region support rib and the downstream support portion, and FIG. 7 is an enlarged sectional view taken along line XX in FIG. 7, FIG. 11 is an explanatory diagram of operation, FIG. 12 is an enlarged sectional view of a main part showing another embodiment of one long region support rib, and FIG. FIG. 14 is an enlarged perspective view of a main part showing a second embodiment of the recording area without recording, and FIG. 14 is an enlarged sectional view taken along line XIV-XIV in FIGS. It is. 15 is an enlarged perspective view of a main part showing a third embodiment in the recording area ENR of the platen, FIG. 16 is an enlarged perspective view of a main part showing a fourth embodiment in the recording area ENR of the platen, and FIG. 17 is a recording area ENR. FIG. 6 is a plan view showing another embodiment of the arrangement of the recording area EAR.

  An image recording apparatus 1 according to an embodiment of the present invention is a multi-function device (MFD) having a printer function, a copy function, a scanner function, and a facsimile function, but the present invention is an inkjet printer having a simple printer function. You may apply to an apparatus. In this embodiment, paper P such as paper or plastic film is used as the recording medium. However, the present invention is not limited to this, and various recording media can be used.

  As shown in FIG. 1, the inside of the opening 2a on the front side (left side in FIG. 1) of the housing 2 as a recording device body made of synthetic resin in the image recording apparatus 1 is partitioned vertically, and below the opening 2a. On the side, an insertable paper feed cassette 3 for feeding a recording medium (paper P) is arranged. The upper side of the opening 2a functions as a paper discharge port through which the recorded paper P is discharged.

  In the present embodiment, the paper feed cassette 3 is configured such that the short side of the paper P cut into, for example, A4 size, letter size, legal size, etc. as a recording medium has a paper transport direction (sub-scanning direction, X-axis direction). A plurality of sheets are stacked and stored so as to extend in an orthogonal direction (a direction orthogonal to the paper surface in FIG. 1, the main scanning direction, and the Y-axis direction) (see FIG. 3). Note that an auxiliary support member 3a that supports the rear end portion of a long sheet P of a legal size or the like is attached to the front end of the paper feed cassette 3 so as to be movable in the X-axis direction. When using A4 size paper P that does not fit in the paper feed cassette 3 (does not protrude from the opening 2a to the outside of the housing 2), the auxiliary support member 3a is fed to the front of the paper feed cassette 3. It can be stored so as not to obstruct the paper. On the upper surface of the paper feed cassette 3, an auxiliary paper feed cassette unit 30 for accumulating and storing small size paper such as postcard size is mounted so as to be movable in the X-axis direction. A downstream side of the auxiliary paper feeding cassette unit 30 in the paper conveyance direction is a paper discharge tray unit 30a (see FIG. 3).

  In addition, an inclined separation plate 8 for paper separation is disposed on the back side (right side in FIG. 3) of the paper feed cassette 3. In addition, an arm 6a whose upper end is rotatable in the vertical direction is mounted in the housing 2, and a paper feed roller 6 provided at the lower end of the arm 6a and a separation claw 8a in the inclined separation plate 8 The paper P, which is the recording medium, accumulated in the paper feed cassette 3 is separated and conveyed one by one. The separated sheet P is fed to a recording unit 7 provided on the upper side (high position) behind the sheet feeding cassette 3 through a U-turn path (feeding path) 9 facing upward. As will be described in detail later, the recording unit 7 includes a reciprocating carriage 5 on which an ink jet recording type recording head 4 for realizing a printer function and the like is mounted. The paper P recorded by the recording unit 7 is discharged in the direction of arrow A toward the paper discharge tray unit 30a with its recording surface facing upward.

  An image reading device for reading a document in a copy function or a facsimile function is disposed on the housing 2. This image reading device is configured to be capable of opening and closing up and down with respect to one side end of the housing 2 via a pivot portion (not shown), and the rear end of the document cover 13 covering the upper surface of the image reading device is an image reading device. It is attached to the rear end so as to be rotatable up and down around the pivot axis.

  A document that is provided so that the document cover body 13 is opened on the upper side and a document is placed on the placement glass plate, and can be reciprocated in the main scanning direction (Y-axis direction) below the placement glass plate. An image on a manuscript paper is read by a reading image scanner device (CIS: Contact Image Sensor).

  On the upper side of the housing 2, an operation panel unit 14 including various operation buttons and a liquid crystal display unit is provided in front of the document cover body 13. An external memory insertion portion 11 for inserting an external memory is provided on the front surface of the housing 2 and below the operation panel portion 14. The external memory is, for example, CompactFlash (registered trademark), SmartMedia (registered trademark), Memory Stick (registered trademark), SD card (registered trademark), xD (registered trademark), or the like.

  As shown in FIG. 2, the recording unit 7 is supported by a pair of left and right side plates 21a and 21b in a main frame 21 made of a metal plate or the like, and extends in the Y-axis direction (main scanning direction). 22, 23, a carriage 5 that is slidably supported (mounted) across both guide members 22, 23 and configured to be reciprocally movable, and a carriage 5 on which the recording head 4 is mounted are reciprocated. In order to achieve this, a timing belt 25 arranged in parallel with the upper surface of the guide member 23 arranged on the downstream side in the paper transport direction (arrow A direction), and a CR (cage) motor 24 (which drives the timing belt 25) In the embodiment, although it is a DC motor, other motors such as a stepping motor may be used.) And a substantially flat plate-like plastic that supports the paper P conveyed on the lower surface side of the recording head 4. It includes a down 26, a tape scale or the like for detecting the Y-axis direction (main scanning direction) position in the main scanning direction (Y axis direction) are arranged so as to extend along the carriage 5. However, in FIG.4 and FIG.5, the state which removed the guide member 23 of the conveyance direction downstream is shown.

  In addition, a pair of registration rollers 27 is arranged on the upstream side of the conveyance with the platen 26 interposed therebetween, and the paper P is fed to the lower surface of the recording head 4. On the downstream side of the platen 26, a paper discharge roller pair 28 including a spur 28a that contacts the image forming surface (front surface) of the paper P and a paper discharge driving roller 28b on the back side is disposed, and the recorded paper P is discharged. It is conveyed to the tray part 30a.

  Further, outside the width of the conveyed paper P (short side of the paper P), an ink receiving portion 29 is provided on one end side thereof (in the embodiment, a portion close to the left side plate 21a in FIG. 3), and the other end. Maintenance units 35 are arranged on the sides (portions close to the right side plate 21a in FIG. 2). The maintenance unit 35 is attached to the pair of guide members 22 and 23. As a result, the recording head 4 periodically discharges ink to prevent nozzle clogging during a recording operation at the flushing position provided in the ink receiving portion 29, and receives ink at the ink receiving portion 29. In the maintenance unit 35, the carriage 5 is in a standby position and cleans the nozzle surface of the recording head 4, selectively sucks ink for each color, or in a buffer tank (not shown) on the recording head 4. Perform a recovery process to remove bubbles.

  An ink reservoir 15 is disposed on one side of the front part in the housing 2 (right side in FIG. 2). The ink storage unit 15 is opened toward the upper side of the housing 2, and each of four colors (black (BK), cyan (C), magenta (M), and yellow (Y)) of ink for full-color recording is used. The stored rectangular ink cartridges 19 having a small area in plan view and a high height can be stored in a line, and each ink cartridge 19 can be detached from the front by opening the lid 2b on the front surface of the housing 2. It is comprised so that.

  Ink is supplied from each ink cartridge 19 to the ink jet recording head 4 via a plurality (four in the embodiment) of ink supply pipes (ink tubes) 20.

  Next, the configuration of the platen 26 will be described in detail with reference to FIGS.

  The image recording apparatus 1 according to the present invention has a mode capable of image recording (edgeless image recording) from the leading edge to the trailing edge of the paper P conveyed in the arrow A direction. In borderless image recording, the left and right side edges (both side edges in the Y-axis direction) of the paper P are also recorded. The user can selectively execute the borderless image recording mode and the bordered image recording mode by a selection command.

  As shown in FIGS. 4 to 6, the platen 26 in the present embodiment is a box-shaped synthetic resin molded product having a substantially rectangular shape in plan view. The platen 26 is configured by integrally forming a shelf plate 40 (refer to FIG. 8: corresponding to the bottom plate in the claims), a concave plate 42 and a stepped shelf plate 43. The shelf plate 40 has a length slightly longer than the short side width of the maximum size (for example, A4 size) paper among the standard sizes of the recording paper that can be used in the image recording apparatus 1 and faces the back surface of the paper P. It is a flat plate. The concave plate 42 is provided on the upstream side in the transport direction with respect to the shelf plate 40, and has a U-shaped cross section that is open upward. The step-down shelf plate 43 is provided at a downstream end portion in the transport direction with respect to the shelf plate 40, and is provided at a position lower than the shelf plate 40 by an appropriate size. The downstream end of the shelf board 40 and the step-down shelf board 43 are connected by a long groove 41 (see FIG. 8) along the Y-axis direction.

  On the upper surface of the shelf board 40, the recording area ENR and the recording area EAR are formed so as to overlap in plan view. The width dimension W1 of the recording area EAR corresponds to a value obtained by adding a small dimension to the width dimension of the short side of the large size sheet (for example, A4 size). On the other hand, the recording area ENR is located in the center of the flat shelf 40 in the Y-axis direction (see FIGS. 5 and 6). In the image recording apparatus according to the present embodiment, when recording an image, such as a postcard or photo L-size paper or an A4 size paper, the center line in the Y-axis direction of each paper is the recording area ENR in the Y-axis direction. A so-called center cash register configuration that almost passes through the center line is adopted. Accordingly, the dimension W2 in the Y-axis direction in the recording area ENR is a value obtained by adding a small dimension (for example, about 10 mm in total on the left and right sides) to the width dimension of the short side of the paper such as the L size of a postcard or a photograph. Equivalent to.

  The dimension L2 in the X-axis direction in the recording area ENR is longer than the dimension L1 in the X-axis direction in the recording area EAR. In borderless image recording using only the recording area ENR, ink can be ejected from all nozzles (not shown) arranged in a line in the X-axis direction in the recording head 4. Therefore, the dimension L2 in the X-axis direction of the recording area ENR corresponds to a value obtained by adding a slight dimension to the lengths of the ink ejection areas from all the nozzles arranged in a line in the X-axis direction in the recording head 4. On the other hand, in borderless image recording using both the recording area EAR and the recording area ENR, image recording is performed by ejecting ink from only a part of the nozzles arranged in the X-axis direction. Therefore, the dimension L1 in the X-axis direction in the recording area EAR is set short.

  A plurality of upstream ribs 44 extending in the X-axis direction extend in the Y-axis direction so as to extend from the recording plate EAR and the recording region ENR to the upstream portion in the transport direction of the shelf plate 40 and the shelf plate 40. They are arranged at appropriate intervals. The sheet P can be supported by the upper end surface of the upstream rib 44.

  In the recording area EAR and the recording area ENR, a plurality of ink flow channel grooves 54 that are open upward such as a V-shaped cross section are formed on the shelf plate 40 between the plurality of in-area support ribs 50, 51. (See FIGS. 5 to 8). The height of the ink channel groove 54 is set to be considerably lower than the height of the in-region support rib 50 (51). Therefore, the ink flow path groove 54 extends toward the downstream side in the transport direction, and is formed to be inclined slightly downward toward the downstream side, and is connected to the concave groove 41. Further, the concave groove 41 communicates with a storage portion 46 in which the ink absorber 45 is stored. An ink absorber 45 that absorbs surplus ink is disposed on almost the entire surface of the housing portion 46. The ink absorber 45 is made of a porous material such as polyurethane foam. The height of the ink absorber 45 is set so as not to contact the lower surface of the downstream support portion 47. Accordingly, of the ink ejected from the nozzles of the recording head 4, the waste ink that has not been received by the paper P is absorbed and captured by the ink absorber 45 in the housing portion 46 from the ink flow channel groove 54 through the concave groove 41. Is done.

  A downstream support portion 47 extending in the Y-axis direction is detachably attached to the upper side of the stepped shelf plate 43 so as to cover the upper side of the storage portion 46 that can store the ink absorber 45. A top 48 is integrally formed at the downstream end portion in the transport direction of the downstream support portion 47. The top 48 is formed so as to extend in a direction along the surface of the platen 26 and in a direction perpendicular to the transport direction. In the embodiment, the top portion (also referred to as a protruding portion) 48 is formed in a substantially triangular shape when the platen 26 is viewed from the side surface (see FIG. 6).

  In the recording area EAR and the recording area ENR, a plurality of in-area support ribs 50 and 51 are provided on the shelf 40 so as to extend at appropriate intervals in the Y-axis direction and along the X-axis direction. . Therefore, the length of the in-region support rib 50 in the recording region EAR (referred to as the length in the X-axis direction, hereinafter the same) is set shorter than the length of the in-region support rib 51 in the recording region ENR. The in-region support ribs 50 and 51 are formed so as to protrude upward from the surface (upper surface) of the shelf board 40 over the entire length thereof. The heights of the upper end surfaces (guide surfaces of the paper P) of all the in-region support ribs 50 and 51 are set to be lower than the upper end of the top portion 48.

  In addition, a center line in the width direction (hereinafter also referred to as the width direction) orthogonal to the conveyance direction of the paper P is a predetermined position in a direction orthogonal to the conveyance direction of the platen 26 (for example, half the length of the platen 26 in the Y-axis direction). When the paper P is conveyed so as to pass through the position, the center position in the width direction, the one in-region support rib 51a corresponds to the predetermined position (for example, the center position in the width direction of the platen 26). Is provided. “Equivalent here” means that the extension line of the center line extending in the X-axis direction of the one in-region support rib 51a passes through the center position in the width direction of the platen 26 in plan view of the platen 26. Or an extension of the center line is arranged so as to pass with a slight displacement with respect to the center position of the platen 26 in the width direction.

  In other words, “corresponding here” means that a pair of side edges extending in parallel with the transport direction in the paper P is a predetermined position in the direction orthogonal to the transport direction in the platen 26 (for example, the center position in the width direction). When configured so as to pass through substantially symmetrical positions, it means that one in-region support rib 51a is also provided at a position corresponding to a predetermined position (for example, the center position in the width direction). .

  At least one in-region support rib 51a among the plurality of in-region support ribs 51 in the recording region ENR is formed longer than the other in-region support ribs 51, and the top portion 48 on the transport upstream side in the downstream support portion 47. It extends so as to be close to. In that case, a longitudinally long groove 52 that opens toward the upstream side of the top portion 48 is formed on the upstream side of the conveyance. The width dimension W4 of the vertically long groove 52 is larger than the plate thickness W5 of the corresponding one in-region support rib 51a (see FIGS. 9 and 11). In the plan view of the platen 26, the transport downstream end 51aa of the at least one in-region support rib 51a enters the width dimension W4 of the vertically long groove 52. As a result, the transport downstream end 51aa of the at least one in-region support rib 51a fits into the longitudinal groove 52 when the platen 26 is projected from the side and overlaps with a part of the downstream support 47. (See FIGS. 7 to 10). Moreover, the transport downstream end 51aa is discontinuous (not connected) with the upstream vertical wall of the top 48 of the downstream support portion 47.

  In addition, the downstream end portion of the in-region support rib 51 other than the at least one in-region support rib 51a and the in-region support rib 50 in the recording region EAR is also the upstream vertical wall of the top portion 48 of the downstream support portion 47. Discontinuous (not connected).

  In the first embodiment, at least one long in-region support rib 51a of the plurality of in-region support ribs 51 has the same height H1 with respect to the nozzle surface (lower surface) 4a of the recording head 4. (Refer to FIG. 8 and FIG. 10). The length L3 in the X-axis direction in the print area of the nozzle surface 4a is shown in FIGS. The one intra-region support rib 51a is set to be higher than the heights of the other plural intra-region support ribs 51 in the recording region ENR.

  With this configuration, when the small-size paper P for borderless recording is supported and transported across the upstream rib 44 and the top 48 on the downstream side of the transport, the back surface of the paper P is the entire area. It does not contact the upper end surface (guide surface) of the inner support rib 51. However, in the state where the leading end of the paper P does not reach the top 48 (the state where the paper P is only supported by the upstream rib 44 only), the edgeless image recording causes the ink to get wet. The leading edge of the paper P may curl downward (see FIGS. 10 and 12). At that time, the leading edge of the paper P moves downstream while contacting the upper end surface (guide surface) of at least one long in-region support rib 51a that is taller than the other in-region support ribs. For example, the paper P is transported such that the center line in the width direction orthogonal to the transport direction of the paper P passes through a predetermined position in the direction orthogonal to the transport direction of the platen 26 (for example, the central portion in the longitudinal direction of the platen 26). In this case, the height of one in-region support rib 51a arranged at a position corresponding to a predetermined position among the plurality of in-region support ribs 51 arranged at appropriate intervals in the direction orthogonal to the conveying direction in the platen 26. However, if the height is set to be higher than the height of the support ribs 51 in the other areas, the central portion in the width direction of the small-size paper P first moves to the top portion 48. The ink channel groove 54 that is the ink discarding portion is not touched.

  When the platen 26 is viewed from the side, the downstream end 51aa of the at least one long region support rib 51a is formed so as to overlap with a part of the downstream support 47. When the leading edge of the sheet P exceeds the downstream end 51aa of the transport, it can immediately transfer to the top 48 on the downstream side of the transport. Accordingly, since the central portion in the width direction of the small-sized paper P first moves to the top portion 48, the left and right side edges of the paper P do not touch the ink flow path groove 54 which is an ink discarding portion described later.

  Even in the case of recording with a border, since the downstream end of the conveyance in all of the in-region support ribs 50 and 51 is not continuous with the upstream vertical wall of the top portion 48, the ejected ink is supported in the region. Even if the ink adhering to the upper end surface (guide surface) of the rib 50 (51) diffuses to the downstream end of the conveyance due to capillary action, the ink does not diffuse to the top 48 side. It is not stained with ink.

  A concave portion 53 that is opened upward is formed at a position corresponding to the in-region support ribs 50 and 51 in the transport direction in the top portion 48 (see FIGS. 6 to 11). This corresponds to the fact that the in-region support ribs 50 or 51 are positioned within the width dimension W3 of the concave portion 53 in the y-axis direction in the plan view of the platen 26 (or the in-region support ribs in the plan view of the platen 26. 50 (51) means that the extension of the center line extending in the X-axis direction passes through the width dimension W3 of the recess 53 (see FIGS. 9 and 11). With this configuration, the leading end (leading edge) of the paper P to be transported rubs against the upper end surface (guide surface) of the in-region support rib 50 (51), and ink is applied to the leading end of the paper P. Even if the ink adheres, the ink adhering portion passes through the width dimension W3 of the concave portion 53. In other words, the top 48 extending in the Y-axis direction does not contact the ink adhering portion. It is possible to prevent the ink adhering portion from spreading in the Y-axis direction. Further, since the ink does not transfer from the ink adhering portion at the leading end portion (leading edge) of the preceding paper P to the top portion 48, even if the back surface of the succeeding paper P contacts (scratches) the top portion 48. It is possible to reliably prevent the back surface of the subsequent paper P from being stained with ink.

FIG. 12 shows another embodiment of at least one long in-region support rib 51a in the recording region ENR. In this embodiment, when the in-region support rib 51a is viewed from the side of the platen 26, the height of the in-region support rib 51a is low at the midway portion 60 in the transport direction in the recording region, and in the transport direction. The downstream inclined surface 61 and the upstream inclined surface 62 are provided so that the height at the downstream end and the upstream end is increased. The downstream inclined surface 61 and the upstream inclined surface 62 are connected to a midway portion 60 having a horizontal plane higher than the surface of the shelf board 40. In this configuration, when the length of the recording head 4 along the transport direction is long, that is, when the recording area is long in the direction of the transport direction, the leading edge or the trailing edge of the paper P contacts the surface of the shelf board 40. This is particularly effective. The height of the midway portion 60 is approximately the same as the height of the other plurality of in-region support ribs 51.
With this configuration, when the paper P is transported in a state where it is only supported by the upstream rib 44, the center of the paper width of the leading edge (tip edge) of the paper P faces the downstream side. Since it is guided in the direction of the top 48 while sliding on the downstream inclined surface 61 of the upward slope, it is easy to transfer to the top 48 first. Further, the in-region support rib 51a has a low height at the midway portion 60 in the transport direction in the recording region and a high height at the downstream end and the upstream end in the transport direction. Since the side inclined surface 61 and the upstream inclined surface 62 are provided, when the length of the recording head 4 along the conveyance direction is long, that is, when the recording area is long in the direction along the conveyance direction, the leading edge of the paper P This is particularly effective because the edge and the rear edge do not contact the surface of the shelf board 40. The height of the midway portion 60 is approximately the same as the height of the other plurality of in-region support ribs 51.

  On the other hand, when the front half of the sheet P to be transported is one-side supported by the downstream support portion 47 and the rear end of the sheet P is disengaged from the downstream end of the upstream rib 44 in the transport direction, If the height of the upstream end is low, the trailing edge of the paper P will drop significantly. As a result, the posture of the rear end side of the paper P changes greatly in the print area L3, so that the image recording quality deteriorates. As in the present embodiment, on the upstream inclined surface 62 that is inclined upward toward the upstream side, the difference in height (drop) at the downstream end in the transport direction of the upstream rib 44 is reduced. The edge is not greatly depressed, and the image recording quality is maintained.

  In the embodiment, the one long in-region support rib 51a and the upstream rib 44 of any of the above shapes in the recording region ENR are arranged such that the central axis extending in the X-axis direction is substantially located on the same line. . Further, the upstream end of the in-region support rib 51 a is connected to the downstream end of the upstream rib 44. Further, the height of the upstream end of the in-region support rib 51a and the height of the downstream end of the upstream rib 44 are set to be substantially the same (see FIG. 12). With this configuration, the trailing edge of the paper P does not drop significantly, and the image recording quality is maintained.

  In the second embodiment, as shown in FIG. 13, the upstream end 51ab in the transport direction of the other plurality of support ribs 51 in the recording area ENR abuts on the boundary wall 55 on the upstream side of the recording area ENR. It is connected continuously. The downstream end of the upstream rib 44 in the transport direction extends beyond the boundary wall 55 by a dimension L4 on the downstream side. Therefore, when the platen 26 is viewed from the side, the upstream end 51ab in the transport direction and the downstream end of the upstream rib 44 in the transport direction are overlapped by a dimension L4 (FIG. 13). And FIG. 14).

  In that case, the plurality of in-region support ribs 51 are arranged at positions that are appropriately deviated by distances W6 to W7 in the direction orthogonal to the transport direction (Y-axis direction) with respect to the upstream ribs 44 (see FIG. 13). . Further, the height H2 of the upstream end 51ab of each of the plurality of in-region support ribs 51 is set to be lower than the height H3 of the downstream end of the upstream rib 44 (see FIG. 14). That is, the downstream end of the upstream rib 44 is formed so as to climb over the boundary wall 55.

  With this configuration, when a borderless image is recorded on the small size paper P by the recording head 4 in the recording area ENR, the ink ejected to the position protruding from the rear edge of the paper P is placed on the support ribs 51 in the area. Most of the ink adheres to the end surface (guide surface) and falls into the ink flow channel groove 54, but a small amount of ink travels along the upper end surface (guide surface) of the in-region support rib 51, and upstream in each in-region support rib 51. It can be set to accumulate at the intersection between the side end 51ab and the boundary wall 55.

  The front half of the sheet P on which the borderless image is recorded and conveyed is one-side supported by the downstream support portion 47, and the rear edge of the sheet P rests on the downstream end in the conveyance direction of the upstream rib 44. In some cases, the height of the portion is high, and the downstream end of the upstream rib 44 in the transport direction and the upstream end 51ab of the in-region support rib 51 are appropriately displaced in the Y-axis direction by a distance W6 to W7. Therefore, the ink accumulated at the intersection of the upstream end 51ab and the boundary wall 55 does not touch the rear edge of the paper P. Further, even when the rear edge of the paper P is transferred to the in-region support rib 51 side, it is already positioned on the downstream side in the transport direction from the intersection between the upstream end 51ab and the boundary wall 55. The ink collected at the intersection does not touch the rear edge of the paper P, and does not stain the rear edge of the paper P, and the ink is downstream of the upper end surface (guide surface) of the in-region support rib 51. It does not spread and the subsequent paper P is not soiled.

  Further, the downstream end of the upstream rib 44 in the transport direction extends beyond the boundary wall 55 and into the recording area ENR, so that the trailing edge of the sheet P extends from the downstream end of the upstream rib 44 in the transport direction. When the paper P is conveyed so as to be detached, it is supported by the upper end surfaces (guide surfaces) of the plurality of in-region support ribs 51, so that the rear end edge of the paper P does not drop greatly downward, and the image recording quality is maintained. The

  If the leading edge of the paper P that is moved downstream in the transport direction while being supported by the top portion 48 in the downstream support portion 47 is lifted, a paper jam occurs before reaching the downstream discharge roller 28b and spur 28a. Therefore, by providing a separate spur roller 56 on the upstream side (see FIG. 8 and FIG. 10), it is possible to prevent the paper P from being lifted especially on the front side.

  Further, the sheet discharge roller 28b (corresponding to the roller body in the claims) provided on the downstream side in the transport direction with respect to the downstream support portion 47 starts from the position corresponding to the in-region support rib 51 (50) in the transport direction. If it is arranged so as to be appropriately displaced in the direction along the surface of the substrate and in the direction perpendicular to the transport direction (Y-axis direction), the upper end surface (guide surface) of the in-region support rib 51 (50) Since the back surface portion of the paper P to which the ink is rubbed does not directly touch the paper discharge roller 28b, the ink stain does not diffuse and the back surface of the subsequent paper P does not get dirty.

  Furthermore, a third embodiment of the in-region support rib 51 is shown in FIG. The one or more in-region support ribs 51 are arranged at positions appropriately deviated by distances W6 to W7 in the direction orthogonal to the transport direction (Y-axis direction) with respect to the upstream ribs 44, and transport the upstream ribs 44. The downstream end in the direction extends beyond the boundary wall 55 by an appropriate size in the recording area ENR (downstream side). Further, the downstream end of the in-region support rib 51 is fitted in the longitudinal groove 52 in the downstream support 47. Therefore, in the side view of the platen 26, the upstream end portion of the in-region support rib 51 overlaps with the downstream end portion of the upstream rib 44, and the downstream end portion of the in-region support rib 51 is the downstream support portion 47. It is comprised so that it may overlap with the upstream edge part.

  According to this configuration, when the rear end edge of the paper P is transported so as to be separated from the downstream end of the upstream rib 44 in the transport direction, it is supported by the upper end surfaces (guide surfaces) of the plurality of in-region support ribs 51. As a result, the trailing edge of the paper P does not drop significantly downward, and the image recording quality is maintained. Further, the ink accumulated at the intersection between the upstream end and the boundary wall 55 does not touch the trailing edge of the paper P. Further, even when the rear edge of the paper P is transferred to the in-region support rib 51 side, the paper P is already positioned on the downstream side in the transport direction from the intersection of the upstream end and the boundary wall 55. The ink collected at the intersection does not touch the rear edge of the paper P, does not stain the rear edge of the paper P, and the ink spreads downstream of the upper end surface (guide surface) of the in-region support rib 51. And subsequent paper P is not soiled. On the other hand, since the downstream end of the in-region support rib 51 overlaps with the upstream end of the downstream support 47, when the leading end of the sheet P exceeds the transport downstream end, the transport downstream side immediately You can transfer to the top 48. Accordingly, since the central portion in the width direction of the small-sized paper P first moves to the top portion 48, the left and right side edges of the paper P do not touch the ink flow path groove 54 which is an ink discarding portion described later.

  FIG. 16 shows a fourth embodiment of one tall intra-region support rib 51a. In this fourth embodiment, the arrangement position of one in-region support rib 51a is arranged at a position appropriately deviated by a distance W8 in the direction (Y-axis direction) orthogonal to the transport direction with respect to the upstream rib 44, and The downstream end of the upstream rib 44 in the transport direction extends beyond the boundary wall 55 by an appropriate size in the recording area ENR (downstream). Further, the downstream end of the in-region support rib 51 is fitted in the longitudinal groove 52 in the downstream support 47. Even if comprised in this way, there can exist an effect similar to the said 3rd Embodiment.

  As shown in FIG. 17, the recording area ENR in which the dimension L2 in the X-axis direction is long is arranged so as to be biased to either the left or right side in the longitudinal direction (X-axis direction) of the platen 26, and the other side. Alternatively, a recording area EAR having a short dimension L1 in the X-axis direction may be disposed. For such a type of platen, it may be set so that one side edge (edge extending in the X-axis direction) of the conveyed paper P is biased to one side plate of the paper feed cassette.

  In the present embodiment, among the standard sizes of recording paper that can be used in the image recording apparatus 1, the maximum size recording paper is A4 size, but it may be A3 size or A3 novi size. In this case, only the width W1 of the recording area EAR is changed, and it goes without saying that the platen can be configured in the same manner as the platen 26 of the present embodiment.

1 is a perspective view of an image recording apparatus of the present invention. It is a top view of a recording part. It is a schematic sectional drawing of a recording part. It is a perspective view in the state where the downstream guide member 23 was removed from the recording part. It is a top view of the state which removed the downstream guide member 23 from the recording part. It is a perspective view of the platen of a 1st embodiment. It is a principal part expansion perspective view which shows the recording area ENR of a platen. FIG. 8 is an enlarged cross-sectional view taken along line VIII-VIII in FIG. 7. It is a partially cutaway enlarged perspective view of an in-region support rib and a downstream support portion. It is sectional drawing which expanded FIG. 8 further. It is an operation explanatory view. It is a principal part expanded sectional view which shows other embodiment of one long in-region support rib. It is a principal part expansion perspective view which shows 2nd Embodiment in the recording area ENR of a platen. FIG. 17 is an enlarged sectional view taken along line XIV-XIV in FIGS. 13, 15, and 16. It is a principal part expansion perspective view which shows 3rd Embodiment in the recording area ENR of a platen. It is a principal part expansion perspective view which shows 4th Embodiment in the recording area ENR of a platen. It is a top view which shows another embodiment of arrangement | positioning of the recording area ENR and the recording area EAR.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image recording apparatus 2 Housing 4 Recording head 5 Carriage 7 Recording part 26 Platen 40 Shelf board 41 as a baseplate Recessed groove 42 Recessed plate 43 Stepped shelf board 44 Upstream rib 45 Ink absorber 46 Storage part 47 Downstream side support part 48 Top 50, 51 Intra-region support rib 51a One long in-region support rib 51aa Downstream end 51ab Upstream end 52 Vertically long groove 53 Recess 54 Ink channel groove 55 Boundary wall 56 Spur roller

Claims (14)

A platen that is opposed to a recording head having nozzles capable of ejecting ink droplets, has a recording area in which ink ejected from the nozzles can land, and supports a recording medium that can be transported along a predetermined direction. And
A plurality of upstream ribs for supporting the recording medium are provided upstream of the recording area in the transport direction, and a downstream support for supporting the recording medium is downstream of the recording area in the transport direction. Part is provided,
In the recording area, at least one in-area support rib capable of supporting the front end and the rear end in the transport direction of the recording medium is provided so as to extend along the transport direction,
The height of the at least one in-region support rib is lower than the height of the upper end surface of the upstream rib and the upper end surface of the downstream support portion, and the upstream rib when the platen is viewed from the side. Alternatively, the platen is formed so as to overlap at least one of the downstream side support portions.   The platen according to claim 1, wherein the in-region support ribs are formed so as to protrude from the surface of the bottom plate of the platen. The upper end surface of the in- region support rib is formed so as to be parallel to a nozzle surface of the recording head from a downstream end to an upstream end in the transport direction. The platen according to 1 or 2.   The height of the support ribs in the region is such that the height in the middle of the transport direction in the recording region is low, and the heights at the downstream end and the upstream end in the transport direction are high. The platen according to claim 1, further comprising a downstream inclined surface and an upstream inclined surface.   5. The platen according to claim 4, wherein a downstream inclined surface and an upstream inclined surface of the in-region support rib are connected to the midway portion having a horizontal plane higher than a surface of the bottom plate. .   6. The platen according to claim 1, wherein an upstream end in the transport direction of at least one of the in-region support ribs is connected to the upstream rib. . Of the in-region support ribs, at least one in-region support rib is disposed at a position appropriately deviated in a direction perpendicular to the transport direction with respect to the upstream rib,
The height of the upstream end of the at least one in-region support rib is set to be lower than the height of the downstream end of the upstream rib. The described platen. The upstream end of the downstream support portion is formed with a top that is higher than the downstream end of the in-region support rib,
The platen according to any one of claims 1 to 7, wherein the top portion is formed so as to extend in a direction along a surface of the platen and in a direction orthogonal to the transport direction.   The platen according to claim 8, wherein a concave portion is formed at a position corresponding to the in-region support rib in the transport direction in the top portion.   A roller body that transports the recording medium is provided downstream of the downstream support portion in the transport direction, and the roller body is disposed from a position corresponding to the in-region support rib in the transport direction. The platen according to any one of claims 1 to 9, wherein the platen is disposed at a position appropriately deviated in a direction along the surface and in a direction perpendicular to the transport direction.   11. The platen according to claim 1, wherein an ink absorber that absorbs excess ink adhering to the recording area is disposed below the downstream support portion. 11.   An ink channel groove extending along the transport direction is formed in the bottom plate between the in-region support ribs in the recording region, and the ink channel groove disposes an ink absorber that absorbs at least excess ink. The platen according to claim 11, wherein the platen is provided so as to communicate with a portion.   When the recording medium is transported so that the center line in the width direction orthogonal to the transport direction of the recording medium passes through a predetermined position in the direction orthogonal to the transport direction of the platen, The height of one in-region support rib arranged at a position corresponding to the predetermined position among the plurality of in-region support ribs arranged at appropriate intervals in a direction orthogonal to the transport direction is within another region. The platen according to any one of claims 1 to 12, wherein the platen is set to be higher than a height of the support rib.   The platen according to any one of claims 1 to 13, a carriage that can reciprocate in a predetermined direction within a main body, and a carriage that is mounted on the carriage and selectively ejects ink droplets from nozzles. A recording head capable of recording an image on a recording medium that can be transported on the platen in a direction orthogonal to the moving direction of the carriage, and the platen and the nozzle surface of the recording head face each other with a predetermined gap. An image recording apparatus characterized by being arranged.

Images