JP2005089076A - Recording medium carrying mechanism and image forming device equipped with the recording medium carrying mechanism, and ink jet recording device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stabilize behavior of a recording medium in delivery of the recording medium to a conveyor belt mechanism on the downstream side to a conveyor belt mechanism on the upstream side. <P>SOLUTION: When paper P conveyed by a conveyor belt 38A of the conveyor belt mechanism 302 is delivered to a conveyor belt 38B of the conveyor belt mechanism 304 on the downstream side, a front end of the paper turns upward. An angle at which the front end of the paper P turns upward are determined according to printing coverage (printing area ratio on the recording medium), type of the paper P, feeding speed of the paper P, size of the paper P. The angles at which the front end turns upward is calculated by combining one or the plurality of such conditions, a paper feeding frame is turned and an upward gradient is set on the conveyer belt 38B based on the result of the calculation. Even if the front end of the paper P turns upward, since the conveyor belt 38B on the downstream side has the upward gradient in relation to the conveyor belt 38A on the upstream side according to the angles at which the paper P turns upward, the paper P is naturally conveyed without correcting posture of the Paper P. Consequently, since behavior of the paper P is stabilized and the paper P is conveyed smoothly, tilting, jamming, or the like are prevented. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a recording medium conveyance mechanism, an image forming apparatus including the recording medium conveyance mechanism, and an inkjet recording apparatus.

  In an ink jet recording apparatus that records an image by ejecting ink droplets onto a recording medium such as paper, the ink jet recording head is mounted on a moving member such as a carriage, and the ink jet recording head moves in a direction perpendicular to the recording medium conveyance direction. There is a so-called scanning type in which (main scanning) and movement of the recording medium (sub-scanning) are alternately performed.

  By the way, in general, in an ink jet recording apparatus, for example, a so-called dummy jet is used to eliminate clogging of the nozzle, or the nozzle is capped to prevent thickening due to ink drying, and the recovery operation for the nozzle needs to be performed. There is. For this reason, head recovery means (sometimes referred to as a maintenance device or a maintenance unit) is provided in the ink jet recording apparatus to perform these recovery operations.

  In the above-described scanning ink jet recording apparatus, since it is easy to retract the ink jet recording head to a position that does not face the recording medium transport means (transport roller, spur, etc.), head recovery means is provided at this retracted position. There was no particular difficulty in performing the head recovery operation.

  In addition, since a small ink-jet recording head is sufficient (as a minimum necessary configuration, one ink-jet recording head needs only one nozzle), the yield in manufacturing the ink-jet recording head is high.

  However, on the other hand, the reciprocation (main scanning) of the ink jet recording head is indispensable for image recording, so there is a natural limit to the pursuit of high productivity (recording more images on a recording medium per unit time). Has occurred.

  On the other hand, in order to realize high productivity, a long length capable of collectively recording an image of an area that is the same as or larger than the width of the recording medium (the length in the direction perpendicular to the conveyance direction). A so-called full-line head type ink jet recording apparatus has been proposed in which an ink jet recording head is fixed and image recording is performed on the entire image only by conveying the recording medium. This method does not require the reciprocating operation of the ink jet recording head, so that high productivity can be achieved as compared with the scanning method.

  However, since an inkjet recording head having a size larger than the width of the recording medium, that is, a head having thousands to tens of thousands of nozzles must be manufactured as an integral part, the yield may be deteriorated.

  Further, in order to mount the above-described head recovery means in a full-line head type ink jet recording apparatus, a new device is required.

  In such an ink jet recording apparatus, there is described a label printer having a configuration in which a label is transported by a plurality of transport belts, and a recovery system unit is moved in a horizontal direction by a predetermined amount during a head recovery operation. (For example, refer to Patent Document 1).

  However, with the configuration in which the head recovery means is moved in this way, recovery operations (dummy jets, etc.) during continuous image recording cannot be performed, and there is a limit to obtaining high productivity. .

  Therefore, the ink jet recording apparatus described in Japanese Patent Application No. 2003-302800 has the following configuration.

  In this ink jet recording apparatus, a plurality of unit heads (ink jet recording heads) constitute a recording head set arranged along the transport direction of the recording medium.

  The plurality of recording head groups are arranged corresponding to each of a plurality of individual recording areas divided in the width direction of the recording medium. Further, adjacent individual recording areas are arranged at different positions along the transport direction, and the recording head set is separated in the recording medium transport direction when viewed in the recording medium width direction.

  In this way, the recording head group is in a so-called staggered arrangement, and adjacent ones in the recording medium width direction are alternately positioned in the transport direction. That is, as a whole, the recording head set is arranged over the entire width of the recording medium. Therefore, if the recording medium is conveyed by the conveying means, it is possible to perform image recording over the entire width of the recording medium.

  As the recording medium conveying means, two conveying belt mechanisms for conveying the recording medium by the conveying belt are provided on the upstream side and the downstream side.

A plurality of transport belts are arranged in the transport direction at positions avoiding the ink droplet flight trajectory from the unit head, that is, between the individual recording areas and the individual recording areas. Therefore, ink droplets do not adhere to the conveyor belt during image recording. Further, head recovery means corresponding to the unit head on a one-to-one basis is disposed at a position facing the unit head, that is, in a region where the conveyance belt is not disposed (on the ink droplet flight locus). Therefore, so-called dummy jet during image recording is also possible, and high productivity can be obtained.
JP-A-8-132700

  However, when the recording medium is transferred from the upstream conveying belt mechanism to the downstream conveying belt mechanism, particularly when the recording medium is conveyed at high speed, air enters the lower surface of the recording medium and the recording medium is lifted. was there. For this reason, the behavior of the recording medium becomes unstable, and skewing, JAM, image defects, and the like may occur.

  The present invention has been made to solve the above problem, and an object of the present invention is to stabilize the behavior of a recording medium when the recording medium is transferred from an upstream conveying belt mechanism to a downstream conveying belt mechanism. .

  The recording medium conveyance mechanism according to claim 1 is a recording medium conveyance mechanism in which a plurality of conveyance belt mechanisms that convey a recording medium to a print area of a recording head by a conveyance belt are arranged in the conveyance direction of the recording medium. It is characterized in that the downstream conveying belt has an upward slope with respect to the belt.

  In the recording medium conveying mechanism according to the first aspect, the recording medium conveyed to the conveying belt of the upstream conveying belt mechanism is delivered to the conveying belt of the downstream conveying belt mechanism. In such delivery, air enters the lower surface of the recording medium and the recording medium rises.

  However, even if the leading edge of the recording medium is lifted, the downstream conveying belt has an upward gradient with respect to the upstream conveying belt, so that the behavior of the recording medium is stabilized and smoothly conveyed. Accordingly, skew, JAM, image defects, and the like are prevented.

  According to a second aspect of the present invention, there is provided a recording medium conveying mechanism according to the first aspect, wherein the recording medium conveying mechanism includes an angle adjusting mechanism that adjusts the upward gradient of the downstream conveying belt.

  The recording medium conveyance mechanism according to the second aspect has the same effect as that of the first aspect, but at an angle at which the leading end of the recording medium is lifted and is directed upward in the transfer to the conveyance belt of the downstream conveyance belt mechanism. Accordingly, the upward gradient of the downstream conveyor belt is adjusted by the angle adjustment mechanism.

  Accordingly, since the behavior of the recording medium is more stable and smoothly conveyed, skew, JAM, image defects, and the like are prevented.

  According to a third aspect of the present invention, there is provided the recording medium conveying mechanism according to the second aspect, wherein the angle adjusting mechanism adjusts the upward gradient according to the print coverage.

  According to a third aspect of the present invention, the angle at which the leading edge of the recording medium faces upward in the transfer to the conveying belt of the downstream conveying belt mechanism is the print coverage (on the recording medium) printed on the upstream side. Printing area ratio). That is, when the print coverage is large, the leading end portion becomes heavy, and the angle at which the leading end of the recording medium faces upward becomes small.

  Therefore, the angle adjustment mechanism adjusts the upward gradient of the downstream conveyor belt according to the print coverage. That is, when the print coverage is large, the upward gradient of the downstream conveyor belt is decreased, and when the print coverage is small, the upstream gradient of the downstream conveyor belt is increased so that the leading edge of the recording medium faces upward. The downstream conveyor belt rises according to the angle and is smoothly conveyed.

  According to a fourth aspect of the present invention, there is provided the recording medium conveying mechanism according to the second or third aspect, wherein the angle adjusting mechanism adjusts the upward gradient according to the type of the recording medium.

  In the recording medium conveyance mechanism according to the fourth aspect, the angle at which the leading edge of the recording medium faces upward in the transfer to the conveyance belt of the downstream conveyance belt mechanism depends on the type of the recording medium. That is, in a recording medium that is weak, such as plain paper, the leading edge is turned up and the angle is increased. On the other hand, a stiff recording medium, such as thick paper or coated paper, has a small angle at which the tip is upward because the tip is difficult to turn.

  Therefore, the angle adjustment mechanism adjusts the upward gradient of the downstream conveying belt in accordance with the type of recording medium. That is, when the recording medium is weak, the upstream gradient of the downstream conveying belt is increased, and when the recording medium is strong, the upstream conveying belt is decreased to reduce the leading edge recording of the recording medium. The downstream conveyor belt rises according to the angle at which the leading edge of the medium faces upward, and is smoothly conveyed.

  According to a fifth aspect of the present invention, there is provided the recording medium transport mechanism according to any one of the second to fourth aspects, wherein the angle adjusting mechanism adjusts the upward gradient according to the transport speed of the recording medium. Yes.

  In the recording medium conveying mechanism according to the fifth aspect, the angle at which the leading end of the recording medium faces upward depends on the conveying speed of the recording medium when the recording medium is conveyed to the conveying belt of the downstream conveying belt mechanism. That is, when the conveyance speed of the recording medium is high, the tip is lifted, so that the angle at which the tip is directed upward is increased. On the other hand, when the conveyance speed of the recording medium is low, the tip does not float so much, so the angle at which the tip faces upward is small.

  Therefore, the angle adjusting mechanism adjusts the upward gradient of the downstream conveyance belt in accordance with the conveyance speed of the recording medium. That is, when the conveyance speed of the recording medium is low, the upstream gradient of the downstream conveyance belt is reduced, and when the conveyance speed of the recording medium is high, the upstream gradient of the downstream conveyance belt is increased. As a result, the downstream conveyor belt rises according to the angle at which it faces upward, and is smoothly conveyed.

  According to a sixth aspect of the present invention, there is provided the recording medium transport mechanism according to any one of the second to fifth aspects, wherein the angle adjusting mechanism adjusts the upward gradient according to the size of the recording medium. .

  In the recording medium conveying mechanism according to the sixth aspect, the angle at which the leading end of the recording medium faces upward depends on the size of the recording medium in the delivery to the conveying belt of the downstream conveying belt mechanism. That is, when the size of the recording medium is small, the angle at which the tip faces upward is small. On the other hand, when the size of the recording medium is large, the angle at which the tip faces upward becomes large.

  Therefore, the angle adjustment mechanism adjusts the upward gradient of the downstream conveyance belt in accordance with the size of the recording medium. That is, when the size of the recording medium is small, the ascending slope of the downstream conveying belt is reduced, and when the recording medium size is large, the ascending slope of the downstream conveying belt is increased so that the leading edge of the recording medium is increased. As a result, the downstream conveyor belt rises according to the angle at which it faces and is smoothly transported.

  According to a seventh aspect of the present invention, there is provided the recording medium conveying mechanism according to any one of the first to sixth aspects, wherein a guide plate for discharging the recording medium is provided on the downstream side of the most downstream conveying belt mechanism. The guide plate has an upward slope with respect to the conveyance belt of the most downstream conveyance belt mechanism.

  The recording medium conveyance mechanism according to claim 7 is provided with a guide plate for discharging the recording medium on the downstream side of the most downstream conveyance belt mechanism, and is conveyed to the conveyance belt of the most downstream conveyance belt mechanism. The recorded medium is discharged to the guide plate. Also in the discharge to the guide plate, the leading edge of the recording medium floats and faces upward.

  However, even if the leading edge of the recording medium faces upward, the guide plate is inclined upward with respect to the conveying belt of the most downstream conveying belt mechanism, so that the behavior of the recording medium is stabilized and discharged smoothly. Accordingly, skew, JAM, image defects, and the like are prevented.

  According to an eighth aspect of the present invention, there is provided a recording medium conveying mechanism according to any one of the first to seventh aspects, wherein an adsorption means for adsorbing the recording medium to the conveyance belt is provided.

  The recording medium conveyance mechanism according to the eighth aspect has the same effect as that of the first to seventh aspects. However, since the recording medium is adsorbed and conveyed by the conveyance belt by the adsorption unit, the recording medium is more stable. Can be transported.

  According to a ninth aspect of the present invention, there is provided the recording medium conveyance mechanism according to the eighth aspect, wherein the adsorption force of the adsorption means is greater in the downstream conveyance belt mechanism than in the upstream conveyance belt mechanism. .

  In the recording medium transport mechanism according to the ninth aspect, the recording medium attracted and transported by the transport belt of the upstream transport belt mechanism is transferred to the transport belt of the downstream transport belt mechanism.

  In a state in which the recording medium is straddling the upstream conveying belt and the downstream conveying belt, the adsorption surface of the recording medium is discontinuous, and the behavior of the recording medium, for example, the leading edge of the recording medium flutters. Prone to instability. However, since the suction force of the downstream conveyor belt is greater than the suction force of the upstream conveyor belt, the leading edge of the recording medium can be suppressed. Therefore, the behavior of the recording medium is stabilized.

  Accordingly, the recording medium is stabilized and transported more smoothly, so that skew, JAM, image defects, and the like are prevented.

  According to a tenth aspect of the present invention, there is provided the recording medium conveying mechanism according to the ninth aspect, wherein the adsorption means is a charging means that provides a potential difference between the conveyance belt and the recording medium and adsorbs the recording medium to the conveyance belt. The absolute value of the potential difference with the recording medium conveyed on the conveyance belt is characterized in that the conveyance belt mechanism on the downstream side is larger than the conveyance belt mechanism on the upstream side.

  According to a tenth aspect of the present invention, the charging medium conveys the recording medium by adsorbing the recording medium to the conveying belt by providing a potential difference between the conveying belt and the recording medium by the charging unit. The absolute value of the potential difference between the transport belt and the recording medium transported to the transport belt is larger in the downstream transport belt mechanism than in the upstream transport belt mechanism.

  Therefore, since the suction force of the downstream conveyor belt mechanism is greater than the suction force of the upstream conveyor belt mechanism, the same effect as in the ninth aspect is achieved.

  According to an eleventh aspect of the present invention, there is provided the recording medium conveying mechanism according to the tenth aspect, wherein the charging means is a charging roller that contacts the conveying belt and rotates following the conveying belt to charge the conveying belt.

The recording medium transport mechanism according to claim 11 charges the transport belt by bringing a charging roller to which a predetermined voltage is applied into contact with the transport belt and rotating the charging roller, thereby providing a potential difference between the transport belt and the recording medium. The recording medium is adsorbed and conveyed. Then, by increasing the absolute value of the charging potential of the conveying belt on the conveying belt on the downstream side of the conveying belt on the upstream side, the adsorbing force on the conveying belt on the downstream side is greater than the adsorbing force on the conveying belt on the upstream side. The image forming apparatus according to a twelfth aspect includes the recording medium conveyance mechanism according to any one of the first to eleventh aspects.

  Since the image forming apparatus of the twelfth aspect includes the recording medium conveying mechanism according to any one of the first to eleventh aspects, the recording medium is smoothly and stably conveyed. Therefore, good recording is performed on the recording medium by the recording means.

  An ink jet recording apparatus according to a thirteenth aspect is the image forming apparatus according to the twelfth aspect, wherein the recording means is an ink jet recording means that discharges and records ink droplets on a recording medium conveyed by a conveying belt. Yes.

  In the ink jet recording apparatus according to the thirteenth aspect, the recording medium is smoothly and stably conveyed. Accordingly, the ink droplets ejected from the ink jet recording means are accurately landed at a predetermined position on the recording medium. Therefore, good recording is performed on the recording medium.

  An ink jet recording apparatus according to a fourteenth aspect is the constitution according to the thirteenth aspect, wherein the ink jet recording means is composed of a plurality of unit heads having different ink ejection characteristics provided along the conveyance direction of the recording medium. A plurality of recording heads corresponding to each of a plurality of individual recording areas divided in the recording medium width direction orthogonal to the direction, and arranged at different positions along the transport direction in adjacent individual recording areas A pair of ink receiving means disposed opposite to the ink droplet ejection surface of the unit head and capable of receiving at least the ink ejected from the unit head, and the conveying belt is in a normal direction of the recording medium And is disposed at a position that avoids the ink droplet flight trajectory from the unit head, and is divided into a plurality in the transport direction. To have.

  The ink jet recording apparatus according to the fourteenth aspect has the same effect as that of the thirteenth aspect, but also has the following action.

  In this ink jet recording apparatus, a plurality of recording head groups are arranged corresponding to each of a plurality of individual recording areas divided in the recording medium width direction, and the recording head group corresponds to the entire width of the recording medium as a whole. Can be made. Therefore, if the recording medium is conveyed by the recording medium conveyance mechanism, it is possible to perform image recording over the entire width of the recording medium. Since there is no need to move the recording head set (main scanning), high productivity can be obtained. Since a conveying belt is used as the conveying means, the recording medium can be conveyed with high conveying accuracy while maintaining the flatness of the recording medium, and a high-quality image can be obtained.

  In addition, the plurality of recording head groups are arranged at different positions along the transport direction in the adjacent individual recording areas, and the recording head group is separated in the recording medium transport direction when viewed in the recording medium width direction. ing. In addition, since a plurality of conveying belts, which are conveying means, are arranged in the conveying direction at positions avoiding the ink droplet trajectory from the unit head, ink droplets adhere to the conveying belt during image recording. There is nothing. Also, when the ink receiving means receives ink from the unit head, the flying ink does not adhere to the transport belt. Therefore, a so-called dummy jet during image recording is also possible, and in this respect, high productivity can be obtained.

  Furthermore, since it is not necessary to move the ink receiving means during the dummy jet and it is not necessary to provide an opening in the transport belt, the structure of the ink jet recording apparatus can be simplified and downsized.

  One recording head set includes a plurality of unit heads having different ink ejection characteristics along the transport direction. This “different ink ejection characteristics” broadly includes, for example, ejection of ink droplets of different colors, and different characteristics of ink droplets having different droplet volumes and actually ejected ink droplets. Therefore, as an example, one recording head set is composed of four (or more) unit heads, and at least yellow (Y), magenta (M), cyan (C), and black (K) ink droplets can be ejected. By doing so, a so-called full-color image can be recorded.

  As the ink receiving means, as long as it can receive flying ink by a dummy jet as described above, its function is sufficient, but the ink discharge port is further in close contact with the ink discharge surface of the unit head. May be capped.

  In order to enable recording of the entire width of the recording medium, the recording head set only needs to be arranged in all the individual recording areas. Therefore, the recording medium may be randomly arranged in the recording medium width direction. It is preferable to arrange with a fixed period in the width direction.

  Similarly, the position of the conveyor belt is not limited as long as the recording medium can be reliably transported and the flight trajectory of the ejected ink droplets is avoided. This is preferable for reliable conveyance of the recording medium.

  As described above, according to the present invention, there is an effect of stabilizing the behavior of the recording medium when the recording medium is transferred from the upstream conveying belt mechanism to the downstream conveying belt mechanism.

  Hereinafter, a recording medium transport mechanism of an ink jet recording apparatus according to an embodiment of the present invention will be described with reference to the drawings.

  As shown in FIG. 1B, the inkjet recording apparatus 12 records an image on a paper feed tray 24 that stores paper P, which is an example of a recording medium, and the paper P supplied from the paper feed tray 24. The recording unit 80 includes a paper discharge tray 18 that stacks and stores paper P on which images are recorded by the recording unit 80, and a guide plate 20 that discharges the paper P from the recording unit 80 and guides it to the paper discharge tray 18. doing.

  The paper P in the paper feed tray 24 is taken out one by one by a pip-up roller (not shown) and sent to the recording unit 80.

  As shown in FIG. 3, the recording unit 80 includes paper transport frames 202 and 204 attached to the housing 206. As shown in FIG. 7, the downstream sheet transport frame 204 is rotatable in a substantially horizontal direction and an upper direction with a driving roller 42 described later as a rotation axis. In addition, the rotating rods 214 attached to both ends on the downstream side of the sheet conveying frame 204 rotate along the groove 212 of the housing 206.

  A drive mechanism 210 is disposed below the paper transport frame 204, and the drive rod 208 is moved up and down by an instruction from a control unit (not shown). The drive rod 208 is in contact with the paper transport frame 204. Accordingly, when the drive rod 208 moves up and down, the downstream paper transport frame 204 rotates.

  The paper P is transported in a predetermined transport direction. In each drawing, the paper conveyance direction is indicated by an arrow F, and the paper width direction orthogonal thereto is indicated by an arrow W.

  As shown in FIG. 2A, the recording unit 80 has a recordable region R1 having a width W1 that is approximately the same as or larger than the maximum width W0 of the paper P on which image recording with the ink jet recording apparatus 12 is assumed. Have. For example, assuming A3 size paper, the maximum width W0 (length in the short side direction) is 297 mm. On the other hand, the width W1 of the recordable area R1 is 307.8 mm in this embodiment. It is said.

  In the recordable area R1, a plurality of individual recording areas R2 divided in the width direction of the paper P are assumed. As can be seen from FIG. 1, the recording head set 22 of the present invention is arranged corresponding to each individual recording region R2. The recording head sets 22 are in a so-called staggered arrangement, and those adjacent in the paper width direction are alternately positioned in the transport direction (hereinafter, the print head sets 22 are distinguished on the upstream side and the downstream side in the transport direction). If necessary, the upstream side is shown as a recording head set 22A, and the downstream side is shown as a recording head set 22B). Therefore, on the paper P on which image recording has been completed, the area recorded by the recording head set 22A and the area recorded by the recording head set 22B are alternately arranged in the paper width direction.

  Each of the recording head groups 22 is configured by arranging a plurality of unit heads 26 having different ink ejection characteristics along the paper conveyance direction.

  In the unit head 26, as shown in FIG. 4, a nozzle row 32 is constituted by a plurality of nozzles 28 formed along the paper width direction. From the ink discharge port 30 at the tip of the nozzle 28, image information is obtained. A corresponding ink droplet can be ejected. As can be seen from FIG. 1A, the unit heads 26 are arranged so that both end positions of the nozzle row 32 coincide in the paper width direction in one recording head set 22. Further, when viewed in the paper transport direction, recording is performed so that the dots on the paper P due to the ink droplets ejected from the respective unit heads 26 coincide with each other in the paper width direction without causing a gap. A head set 22A and a recording head set 22B are arranged. Accordingly, each recording head set 22 records an image on the paper P only in the corresponding individual recording region R2, but all the recording head sets 22 can record an image over the entire width of the paper P. As described above, when the unit heads 26 are arranged so that the dots from the unit heads 26 overlap in the paper width direction, the nozzles 28 corresponding to the overlapped portions may not be used. .

  The above “ink ejection characteristics” refers to the characteristics of the ink droplets to be ejected, and includes, for example, the color, volume of the ink droplets, ejection speed, and the like. In this embodiment, the number of unit heads 26 per recording head set 22 is four, and yellow (Y), cyan (C), magenta (M), and black (K) are sequentially arranged from the upstream side in the transport direction. Each color is assigned. As a result, a so-called full-color image can be recorded (hereinafter, when the unit heads 26 need to be distinguished for each color, they are distinguished by adding one of Y, M, C, and K at the end of the code. To do). Of course, other configurations are possible. For example, even if the number of unit heads 26 per recording head set 22 is two, two colors are recorded by assigning different colors to each unit head 26. Is possible. In addition, it is possible to add a color other than YMCK and increase the color reproducibility by setting this number to 5 or more, for example. Furthermore, even the unit heads 26 corresponding to the same color may have different ink droplet volumes so as to have higher gradation.

The recording head set 22 may be configured by unitizing the plurality of unit heads 26 in one recording head set 22, but in this embodiment, the recording head set 22 is shown in FIG. As described above, in each of the recording head sets 22A and 22B, a common substrate 36 is provided for each unit head 26 corresponding to each color, and the recording head unit 34 is configured by attaching the unit head 26 to the common substrate 36. The unit head 26 can be easily assembled. (In FIG. 2 (and FIG. 5 described later), only the print head unit 34 corresponding to a specific color (for example, yellow) is shown for convenience of illustration, but the same applies to other colors.)
That is, the common substrate 36 is spanned in the recording medium width direction and fixed to the paper transport frames 202 and 204, and the common substrate 36 is equally spaced in the paper width direction (the same interval as the width W2 of the individual recording region R2). A plurality of unit heads 26 are attached to form a recording head unit 34.

  In this way, the recording head set 22A is provided with one recording head unit 34 for each color (a total of four in this embodiment), and similarly, the recording head set 22B as a whole has one for each color. The recording head units 34 are provided one by one (four in total). In each recording head unit 34, the unit heads 26 are attached at the same interval as the width W2 of the individual recording region R2, so that the two recording head units 34 corresponding to the same color have exactly the same configuration. By disposing the recording head unit 34 in the paper width direction by shifting the recording head unit 34 by the width W2 of the individual recording region R2, ink droplets can be ejected to the entire width of the paper P. If the recording head unit 34 is made common in this way, the number of parts is reduced, and the recording unit 80 can be configured at low cost.

  In the present embodiment, the length of the nozzle row 32 of the unit head 26 is 25.4 mm. Six unit heads 26 are provided by one recording head unit 34, and two recording head units 34 are provided for each color, so that a 25.4 mm nozzle row 32 is formed as a whole. In the paper width direction, there are no gaps, and the recordable area R1 has a width of 304.8 mm.

  The recording unit 80 includes a recording medium transport mechanism 300 that transports paper. The recording medium transport mechanism 300 includes an upper transport belt mechanism 302 having a transport belt 38A and a downstream transport belt mechanism 304 having a transport belt 38B.

  As shown in FIG. 8, a recording head array 40A composed of recording head units 34Y, 34M, 34C, and 34K for the respective colors is disposed on the upstream side of the conveying belt mechanism 302 on the upstream side. A recording head array 40B is disposed on the top of the recording head array 40B. As described above, the recording head units 34Y, 34M, 34C, and 34K are fixed to the paper transport frames 202 and 204 (see FIG. 3A).

  As shown in FIG. 1B, the paper P in the paper feed tray 24 taken out one by one by a pip-up roller (not shown) is sent to the higher-level transport belt mechanism 302, and then the downstream-side transport belt mechanism. 304. Then, the sheet is discharged onto the guide plate 20 and stacked on the discharge tray 18.

  In the recordable area R1, an area where ink droplets are not ejected from the recording head set 22 (unit head 26) (hereinafter referred to as a non-recording area), that is, a flight trajectory of ejected ink from the unit head 26 is avoided. As shown in FIG. 1A, a conveyance belt 38 is disposed at the position. Since the non-recording areas are alternately positioned in the sheet width direction with the recording head group 22, a plurality of conveying belts 38 are hung at equal intervals in the sheet width direction. Since the upstream side conveyor belt 38A and the downstream side conveyor belt 38B are shifted in the paper width direction by the width of the individual recording region R2, the overall conveyor belt 38 is staggered. Yes.

  Therefore, in the present embodiment, when the recordable area R1 is viewed in the paper width direction, the recording head set 22A or the recording head set 22B is arranged in the individual recording area R2 at a constant period, and further, in the non-recording area, The conveyance belt 38A or the conveyance belt 38B is arranged at a constant cycle, and the recording head set 22 and the conveyance belt 38 are alternately arranged.

  As shown in FIG. 3A, a driving roller 42 is stretched in the sheet width direction at the center of the recording unit 80 in the sheet conveyance direction, and is rotatably supported by the sheet conveyance frames 202 and 204. ing. The upstream side conveyor belt 38 </ b> A and the downstream side conveyor belt 38 </ b> B are alternately wound around the drive roller 42 and held.

  Also, one driven roller 44 is stretched around the upstream end and the downstream end in the paper transport direction, respectively, in the paper width direction, and the driven roller frames attached to the paper transport frames 202 and 204, respectively. 46 is rotatably supported via a bearing or the like. As shown in FIG. 1A, each driven roller 44 includes a shaft 66 and a plurality of pulleys 68 to which the shaft 66 is fixed. Further, the conveyor belt 38A and the conveyor belt 38B are wound around the pulley 68 of the corresponding driven roller 44 and held.

  The drive roller 42 is connected to a drive motor 50 via a gear 48 (or directly), and the drive motor 50 is a drive source for the conveyance belt 38. By rotating the drive roller 42 driven by the drive motor 50, all the conveyor belts 38 can be circulated at the same circulation speed, so that the quality irregularity of the recorded image between the recording head groups 22A and 22B is eliminated. A high-quality image can be obtained. As the drive motor 50, it is preferable to use a stepping motor because it is possible to control the sheet conveyance with high accuracy, but the present invention is not limited to this.

  The drive roller 42 is provided with an encoder 52 so as to output a predetermined pulse in synchronization with the rotation of the drive roller 42. Based on this pulse, the drive motor control means 54 controls the rotation of the drive motor 50, and for example, the rotation irregularity of the drive roller 42 caused by the output shaft of the drive motor 50, the gear 48, the eccentricity of the drive roller 42, etc. is constant. It can be suppressed within the range.

  The drive motor control means 54 is not limited as long as the above-described control can be performed. For example, the difference from the ideal rotation of the drive roller 42, that is, the eccentricity, from an individual encoder signal when the drive roller 42 rotates. By reading the error component and providing the drive motor 50 with information for canceling the eccentric error component, it is possible to use one that performs eccentric control.

  As shown in FIGS. 2 (B) and 5 (A) to (D), a position facing the unit head 26 across the sheet P to be conveyed, that is, an area where the conveyor belts 38A and 38B are not arranged. The head recovery means 70 corresponding to the unit head 26 on a one-to-one basis is arranged. Although only one head recovery means 70 is shown between the driving roller 42 and the driven roller 44 in the drawing, the number of unit heads 26 is actually provided. Further, in these drawings, the space between the upstream driven roller 44 and the drive roller 42 is shown, but the head recovery means 70 is similarly provided between the drive roller 42 and the downstream driven roller 44. .

  The head recovery means 70 has at least a cap member 72 that opens toward the unit head 26 and a holding member 74 that holds the cap member 72. The holding member 74 is moved up and down (units) by a lifting mechanism (not shown). Approaching and separating from the head 26). Furthermore, a suction means for sucking the inside of the cap member 72 is provided as necessary.

  As shown in FIG. 5D, when the head recovery means 70 is raised, the cap member 72 is in close contact with each ink ejection surface 26A of the unit head 26 so as to surround the nozzle row 32 (see FIG. 4). And capping. This prevents inadvertent drying of the ink, prevents clogging of the nozzles 28 with thickened ink, and prevents ink deterioration. In this state, a so-called vacuum operation is performed, and ink can be forcibly sucked from the nozzles 28 of the unit head 26.

  On the other hand, when the head recovery means 70 is lowered, the sheet P is conveyed by the conveying belts 38A and 38B and can pass under the unit head 26 as shown in FIG. Image recording can be performed. Further, as shown in FIG. 5C, when the paper P is not positioned below the unit head 26 (for example, between two continuous paper P), a so-called dummy jet is performed from the unit head 26. The ink droplet can be received by the cap member 72.

  The lifting mechanism of the head recovery means 70 may be provided individually for each head recovery means 70, or may be provided in common to the plurality of head recovery means 70. When the lifting mechanism is shared by the plurality of head recovery means 70, for example, the plurality of head recovery means 70 can be fixed on a common base plate and the base plate itself can be moved up and down.

  Further, as described above, it is preferable that the head recovery means 70 can perform capping with respect to the unit head 26. However, depending on the configuration of the inkjet recording apparatus 12, at least the ink of the dummy jet can be received. Can be enough.

  In the above, the recording head groups 22A and 22B are arranged in a staggered manner as a whole. However, if the recording head groups 22A and 22B are arranged so as to cover all the individual recording areas as a whole, the recording paper sets 22A and 22B Since image recording over the entire width is possible, a random arrangement in the width direction of the paper P may be used. However, considering the width of the head recovery means 70, for example, the recording head sets 22A and 22B are arranged at a constant cycle in the width direction of the paper P, and between the recording head sets 22A or between the recording head sets 22B. If a certain amount of space is formed, even if the head recovery means 70 is wide, it is preferable because there are less restrictions on the arrangement in which adjacent head recovery means 70 interfere with each other.

  Similarly, the transport belts 38A and 38B may be any positions that can reliably transport the paper P and avoid the flight trajectory of the ink droplets from the unit head 26, but may be randomly arranged in the width direction of the paper P. . However, it is preferable to arrange the paper P in the width direction at regular intervals so that the paper P can be reliably conveyed.

  6 and 8 show the recording medium transport mechanism 300. FIG. As described above, the recording medium conveyance mechanism 300 includes the upstream conveyance belt mechanism 302 and the downstream conveyance belt mechanism 304.

  As shown in FIGS. 6 and 8, charging rollers 100 </ b> B and 100 </ b> C in which the core 104 is rotatably attached to the paper transport frames 202 and 204 are provided below the transport belt mechanisms 302 and 304, respectively. Further, the charging rollers 100B and 100C are in contact with the conveyance surfaces of the paper P of the conveyance belts 38A and 38B, respectively, and are driven to rotate as the conveyance belts 38A and 38B rotate.

  Further, the upstream portion of the upper portion of the upstream conveying belt mechanism 302 is provided with a charging roller 100A having a core 104 rotatably attached to the sheet conveying frames 202 and 204. When the sheet P is conveyed, the sheet is conveyed. Rotate following contact with P.

  These charging rollers 100A, 100B, and 100C are insulated from the paper transport frames 202 and 204, and have a conductive core at the center of a cylindrical conductive rubber portion 102 provided with a high resistance coating layer (not shown). 104 is configured.

  The cores 104 of the charging rollers 100A, 100B, and 100C are connected to an electric circuit (not shown) and applied with a voltage. The applied voltages are VR1v for the upper charging roller 100A, VR2v for the lower upstream charging roller 100B, and VR3v for the downstream charging roller 100C. Further, the relationship between the voltages is | VR1v | <| VR2v | <| VR3v |.

  By contacting and rotating the conveyance belts 38A and 38B and the paper P, the paper P is charged to the charging potential V1v, the conveyance belt 38A is charged to the charging potential V2v, and the conveyance belt 38B is charged to the charging potential V3v. The relationship of | V1v | <| V2v | <| V3v |.

  As shown in FIG. 6, the conductive rubber portions 102 of the charging rollers 100 </ b> A, 100 </ b> B, and 100 </ b> C are provided over the entire region perpendicular to the conveyance direction F of the conveyance belt mechanism 302. Therefore, the charging roller 100A is charged across the entire width direction of the sheet P, and the charging rollers 100B and 100C are contacted and charged over all the corresponding conveying belts 38B and 38A.

  As shown in FIG. 8, a neutralizing brush 120 made of a conductive brush is provided in the vicinity of the upstream side of the driven roller 44 of the downstream conveying belt mechanism 304, and the back surface of the conveying belt 38B (surface for conveying the paper P). The opposite surface). Further, the static elimination brush 120 is connected to a ground (not shown). Therefore, the static elimination brush 120 neutralizes the conveyance belt 38B.

  Further, a static eliminating brush 122 made of a conductive brush is also provided on the upper portion of the driven roller 44 of the downstream side conveyor belt mechanism 304, and comes into contact with the surface of the paper P that has been conveyed on the conveyor belt 38B. The static elimination brush 122 is also connected to a ground (not shown). Accordingly, the static elimination brush 122 neutralizes the paper P.

  The neutralizing brushes 120 and 122 are provided over the entire direction perpendicular to the transport direction F. Accordingly, the neutralizing brush 120 is in contact with the entire conveying belt 38B across the entire width direction of the paper P, and the neutralizing brush 122 is neutralized by discharging.

  As shown in FIG. 7, when the drive rod 208 of the drive mechanism 210 moves up and down, the paper transport frame 204 rotates about the drive roll 42 in the substantially horizontal direction and upward.

  As the paper transport frame 204 rotates, as shown in FIG. 8, the recording head array 40B (recording head unit 34), the transport belt mechanism 304, the charging roller 100C, and the static elimination brush fixed to the paper transport frame 204. 120 and 122 also rotate together.

  As shown in FIG. 1B, the guide plate 20 is inclined upward with respect to the conveyor belt 38B.

  Further, in the ink jet recording apparatus 12 of the present embodiment, the conveyance speed of the paper P is variable. That is, when high image quality is required, the conveyance speed of the paper P can be reduced, and when low image quality is acceptable, or when priority is given to the printing speed, the conveyance speed of the paper P can be increased.

  Next, the operation of the recording medium transport mechanism 300 of the ink jet recording apparatus 12 of this embodiment will be described.

  In a state where there is no instruction from the controller, the inkjet recording apparatus 12 is in a standby state, and each member is stopped. As shown in FIG. 5D, the head recovery means 70 is raised and the cap member 72 is brought into close contact with the ink discharge surface of the corresponding unit head 26 to prevent clogging of the nozzles 28 and ink deterioration.

  When there is an instruction to perform image recording from the controller, the inkjet recording apparatus 12 can first lower the head recovery means 70 and allow the paper P to pass under the unit head 26 as shown in FIG. Like that. At this time, as shown in FIG. 5C, a so-called dummy jet may be performed as necessary to restore the unit head 26 to an optimum state for ink droplet ejection. Since the cap member 72 is positioned below the unit head 26, ink droplets ejected by the dummy jet can be received.

  In accordance with this, the drive motor 50 is driven to rotate the drive roller 42, and the medium transport belts 38A and 38B are driven to circulate. At this time, the drive motor 50 is rotated while performing eccentricity control in response to a signal from the encoder 52.

  As shown in FIG. 8, when the conveying belts 38A and 38B of the conveying belt mechanisms 302 and 304 are rotated, the charging roller 100B and the charging roller 100C are driven to rotate. Since VR2v is applied to the charging roller 100B and VR3v is applied to the charging roller 100C, the conveying belt 38A is charged to the charging potential V2v, and the conveying belt 38B is charged to the charging potential V3v.

  In a state where the circulation speed of the medium transport belts 38A and 38B is stable and charged to the charging potentials V2v and V3v, a controller (not shown) drives a pip-up roller (not shown) to feed the paper feed tray 24 (see FIG. 1B). The paper P is fed one by one to the upstream conveying belt mechanism 302.

  The paper P sent to the upstream conveying belt mechanism 302 contacts the upper charging roller 100A. Since VR1v is applied to the charging roller 100A, the sheet P is charged to the charging potential V1v.

  Since | VR1v (applied voltage to charging roller 100A) | <| VR2v (applied voltage to charging roller 100A) |, | V1v (charging potential of paper P) | <| V2v (conveying belt 38A) Charging potential) |, and a potential difference is provided between the charging potential of the paper P and the conveying belt 38A. Accordingly, the paper P is electrostatically adsorbed to the transport belt 38A.

  Subsequently, the paper P is delivered to the downstream conveying belt mechanism 304. Similarly, | VR1v (voltage applied to charging roller 100A) | <| VR3v (voltage applied to charging roller 100C) |, so | V1v (charging potential of paper P) | <| V3v (conveying belt) The charging potential of the sheet P and the conveying belt 38A is set to a potential difference. Accordingly, the paper P is electrostatically adsorbed to the transport belt 38B.

  In this way, the paper P is electrostatically attracted to the transport belts 38A and 38B and transported, so that the paper P is transported stably.

  When the sheet P conveyed to the conveying belt 38A of the conveying belt mechanism 302 is transferred to the conveying belt 38B of the conveying belt mechanism 304 on the downstream side, air enters the lower surface of the sheet P and the leading end of the sheet P is moved. Float and face up. The angle at which the leading edge of the paper P faces upward is affected by the following conditions.

  The first condition is the effect of print coverage (print area ratio on the recording medium). That is, when the print coverage is large, the tip of the recording medium becomes heavy and the angle at which the tip of the recording medium faces upward is small. On the other hand, if the print coverage is small, the tip portion is light, and the angle at which the tip faces upward increases.

  The second condition is the effect of the type of paper P. That is, in the paper P having weak stiffness, for example, plain paper, the leading edge is easy to turn, so the angle at which the leading edge faces upward is increased. On the other hand, the paper P having a strong stiffness, such as thick paper or coated paper, has a small angle at which the leading edge is upward because the leading edge is difficult to turn.

  The third condition is the influence of the conveyance speed of the paper P. That is, when the conveyance speed of the paper P is fast, the leading edge is lifted, so that the angle at which the leading edge faces upward is increased. On the other hand, when the conveyance speed of the paper P is low, the leading edge is unlikely to rise, so the angle at which the leading edge faces upward is small.

  The fourth condition is the influence of the size of the paper P. That is, when the size of the paper P is small, the angle at which the leading edge faces upward is small. On the other hand, when the size of the paper P is large, the angle at which the leading end faces upward is large.

  In the present embodiment, one or a combination of the first to fourth conditions described above is used, and the angle at which the leading edge of the paper P floats and faces upward is calculated by a control unit (not shown). Based on this result, as shown in FIG. 7, the control unit raises the drive rod 208 of the drive mechanism 210 and rotates the paper transport frame 204 upward. As shown in FIG. 8, when the paper transport frame 204 is rotated upward, the transport belt 38B is also integrally rotated upward, and an optimal upward gradient is transported according to the angle at which the leading edge of the paper P faces upward. Provided on the belt 38B.

  In this way, even when the leading edge of the paper P is lifted when being transferred to the conveying belt 38B of the downstream conveying belt mechanism 304, the upstream side of the conveying belt 38A is in accordance with the angle at which the leading edge of the paper P faces upward. Since the downstream conveying belt 38B has an upward slope, the behavior of the paper P is stabilized and smoothly conveyed. Therefore, skew, JAM, etc. are prevented.

  Further, since the relationship between the voltages applied to the charging rollers 100A, 100B, and 100C is | VR1v | <| VR2v | <| VR3v |, the relationship between the charging potentials of the paper P and the conveying rollers 38A and 38B is | V1v. | <| V2v | <| V3v |. That is, the potential difference between the charging potential V1v of the paper P and the charging potential V3v of the transport belt 38B is larger than the potential difference between the charging potential V1v of the paper P and the charging potential V2v of the transport belt 38A. That is, the suction force that the sheet P is attracted to the downstream conveyance belt 38B is greater than the adsorption force that the sheet P is attracted to the upstream conveyance belt 38A.

  Now, in a state where the paper P straddles the upstream-side transport belt 38A and the downstream-side transport belt 38B, the suction surface of the paper P is discontinuous. For this reason, the behavior of the paper P tends to be unstable, such as the leading edge of the paper P fluttering. However, since the suction force to the downstream conveyance belt 38B is larger than the suction force to the upstream conveyance belt 38A, the behavior of the paper P is stabilized.

  Discharge brushes 120 and 122 connected to a ground (not shown) are provided downstream of the conveyance belt mechanism 304 on the downstream side. For this reason, the conveying belt 38B and the paper P are neutralized, and the charged potential difference between the conveying belt 38B and the paper P is released.

  Accordingly, the paper P that has been transported without the suction force is easily peeled off from the transport belt 38B and discharged onto the guide plate 20. Since the paper discharge tray 18 is also provided with an upward slope with respect to the conveyor belt 38B, the paper is smoothly discharged. Then, the sheets are stacked on the paper discharge tray 18 (see FIG. 1B).

  On the other hand, while the paper P is being transported in this way, ink droplets corresponding to the image information are sequentially ejected from the unit head 26 at the most upstream in the transport direction to a predetermined position on the paper P, and image recording is performed. As described above, since the paper P is smoothly and stably conveyed, the ink droplets can be landed accurately on a predetermined position of the paper P, and good image quality can be obtained.

  In the present embodiment, since the recording head array 40B (recording head unit 34) is fixed to the paper conveyance frame 204, when the conveyance belt 38B has an upward gradient, it integrally has an upward gradient. That is, the distance between the paper P and the unit head 26 is always constant.

  In the ink jet recording method, the distance between the paper P and the unit head 26 greatly affects the print quality. Therefore, as in the present embodiment, a configuration in which the distance between the paper P and the unit head 26 is always constant even when the transport belt 38B has an upward slope is preferable.

  However, for example, if the change in the angle of the upward gradient of the conveyance belt 38B (the distance between the unit head 26 and the paper P) does not affect the print quality or is within a range where the decrease in print quality is acceptable, the conveyance belt 38B. The unit belt 26 may not move integrally, that is, the distance between the unit head 26 and the paper P may not always be constant.

  Now, when the ink droplet ejection from the unit head 26 on the most downstream side in the transport direction is completed, the image recording on the entire paper P is completed, and the paper P passes through the guide plate 20 and the paper discharge tray 18 (FIG. 1 ( B).) At this time, it is determined whether or not a dummy jet is necessary, and if necessary, the dummy jet is performed. When the dummy jet is not necessary, the next sheet P is printed as it is.

  When the image recording on the predetermined number of sheets P is completed, the rotation of the drive motor 50 is stopped and the circulation of the conveyor belts 38A and 38B is also stopped.

  Thereafter, as shown in FIG. 5D, the controller raises the head recovery means 70 and caps each of the unit heads 26 with the cap member 72.

  Thus, a series of image recording operations are completed. In addition, with the unit head 26 capped by the cap member 72, ink suction (vacuum operation) from the unit head 26 may be performed as necessary.

  As described above, the inkjet recording apparatus 12 according to the present embodiment can perform image recording over the entire width only by transporting the paper P without moving the recording head groups 22A and 22B in the paper width direction, and productivity. Becomes higher.

  Moreover, the head recovery means 70 corresponding to each of the unit heads 26 is always opposed to the ink discharge surface 26A, and it is not necessary to move the unit head 26 or the head recovery means 70 when performing the dummy jet. Further, the medium transport belts 38A and 38B are disposed in the non-recording area, and the ink ejected by the dummy jet does not inadvertently adhere to the medium transport belts 38A and 38B. Therefore, for example, dummy jet can be performed in an area between the sheets P while image recording is performed, and high productivity can be obtained also in this respect. In addition, since it is not necessary to move the unit head 26 or the head recovery means 70 during the dummy jet, the structure of the ink jet recording apparatus 12 can be simplified and downsized.

  In addition, this invention is not limited to said embodiment.

  For example, the recording medium conveyance mechanism 300 is composed of two conveyance belt mechanisms 302 and 304 upstream and downstream (see FIG. 1B). However, three or more conveyor belt mechanisms may be provided.

  For example, as shown in FIG. 9, a recording medium conveyance mechanism 400 including three conveyance belt mechanisms 402, 403, and 404 may be used. In addition to this, in addition to the charging rollers 100A, 100B, and 100C, a charging roller 100D is further provided on the downstream side, and in addition to the recording head sets 22A and 22B, a recording head set 22C is further provided on the downstream side. Yes.

  In the case of such a configuration, as shown in FIG. 9, it is only necessary that the downstream conveyor belt has an upward slope. Further, the voltage applied to each of the charging rollers 100A, 100B, 100C, and 100D is | VR1v | <| VR2v | <| VR3v | <| VR4v |, and the charging potential is | V1v (charging voltage of the paper P) | <| V2v. (Charging potential of the conveying belt 38A) | <| V3v (charging potential of the conveying belt 38B) | <| V4v (charging potential of the conveying belt 38C) |

  Further, for example, as shown in FIG. 10B, the driving system is independent for the conveying belt 338A and the conveying belt 338B. That is, the driving roller 520 and the driven roller 510 may be provided corresponding to the conveying belt 338A, and the driving roller 520 and the driven roller 510 may be similarly provided corresponding to the conveying belt 338B. The downstream side conveyor belt mechanism 504 rotates around the driven roller 510 according to the angle at which the leading edge of the paper P rises, and the conveyor belt 338B has an upward gradient.

  Further, for example, as shown in FIG. 10A, the conveyance belt 338A and the conveyance belt 338B may be configured by a single belt. However, in such a configuration, it is not possible to provide the head recovery means 70 corresponding to the unit head 26 in a one-to-one correspondence with the unit head 26 across the conveyed paper P. (See FIGS. 2 and 5). Therefore, during the head recovery operation, it is necessary to move the head recovery means and perform a recovery operation.

  The ink jet recording apparatus of the present invention is widely included as long as it can record an image by ejecting ink droplets onto a recording medium, and is used as an output device such as a facsimile, a copying machine, a printer complex machine, or a workstation. Recording apparatuses are included, and the ink jet recording method of the present invention also includes a storage method for recording an image on a recording medium using these recording apparatuses.

  In addition, the “recording medium” that is the target of image recording in the ink jet recording apparatus of the present invention includes a wide range of objects as long as the ink jet recording apparatus ejects ink droplets. In addition, the dot pattern on the recording medium obtained by attaching the ink droplets on the recording medium is widely included in the “image” or “recorded image” obtained by the recording apparatus of the present invention. Therefore, the ink jet recording apparatus of the present invention is not limited to that used for recording characters and images on recording paper. In addition, the recording medium includes a recording sheet, an OHP sheet, and the like. In addition, for example, a substrate on which a wiring pattern or the like is formed is included. The “image” includes not only general images (characters, pictures, photographs, etc.) but also the above-described wiring patterns, three-dimensional objects, organic thin films, and the like. The liquid to be discharged is not limited to colored ink. For example, production of a color filter for display performed by discharging colored ink on a polymer film or glass, formation of bumps for component mounting performed by discharging molten solder onto the substrate, and organic EL solution on the substrate For general liquid droplet ejecting devices intended for various industrial applications, such as the formation of EL display panels that are ejected onto the substrate and the formation of bumps for electrical mounting that are performed by ejecting molten solder onto the substrate. It is possible to apply the ink jet recording apparatus of the invention.

  Further, the recording means is not limited to the ink jet recording means. For example, a toner jet method may be used in which charged toner is ejected by an electric force from an aperture electrode, and the toner passing through the aperture electrode is attached to a recording medium to form a toner image. A thermal head recording method using a thermal head that is arranged and selectively heats a heating element by energization corresponding to image data may be used. Alternatively, other recording means may be used.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic structure of the inkjet recording device of one Embodiment of this invention is shown, (A) is a top view, (B) is a front view. (A) is explanatory drawing which shows the relationship between the recording head array of the inkjet recording device of one Embodiment of this invention, a paper width, and a recordable area, (B) shows the position of a conveyance belt and a head recovery | restoration means. It is explanatory drawing shown. 1A is a plan view showing the inside of a paper transport frame of an ink jet recording apparatus according to an embodiment of the present invention, and FIG. It is explanatory drawing which shows the unit head of the inkjet recording device of this invention from the ink discharge surface side. FIG. 2A is a plan view, FIG. 3B is a front view, FIG. 3B is a front view, FIG. 3C is a front view, FIG. 1 is a plan view illustrating a schematic configuration of a recording medium transport mechanism of an ink jet recording apparatus according to an embodiment of the present invention. FIG. 3 is a diagram schematically illustrating a state in which a transport frame on the downstream side of the recording medium transport mechanism of the ink jet recording apparatus according to the embodiment of the present invention rotates substantially horizontally and upward. 1 is a side view showing a schematic configuration of a recording medium transport mechanism of an ink jet recording apparatus according to an embodiment of the present invention, in which a recording head hot water unit fixed to a transport frame, a transport belt mechanism, and a charging roller are substantially horizontal and upward. It is a figure which represents a mode that these are rotated. FIG. 6 is a side view illustrating a schematic configuration of a recording medium conveyance mechanism of an inkjet recording apparatus according to another embodiment of the present invention, in which a recording head hot water unit fixed to a conveyance frame, a conveyance belt mechanism, and a charging roller are substantially horizontal and upward. It is a figure which represents a mode that these are rotated. 2A and 2B show a schematic configuration of a recording medium conveyance mechanism of an ink jet recording apparatus according to another embodiment of the present invention, in which FIG. 3A is a plan view, and FIG. FIG. 3 is a side view schematically showing a state in which the oscillates substantially horizontally and upward.

Explanation of symbols

DESCRIPTION OF SYMBOLS 12 Inkjet recording device 22 Recording head group 22A Recording head group 22B Recording head group 22C Recording head group 26 Unit head 38A Conveyor belt 38B Conveyor belt 38C Conveyor belt 42 Drive roller 44 Follower roller (stretching roller)
70 Head recovery means 100A Charging roller 100B Charging roller 100C Charging roller 100D Charging roller 210 Drive mechanism (angle adjustment mechanism)
300 Recording Medium Conveying Mechanism 302 Conveying Belt Mechanism 304 Conveying Belt Mechanism P Paper R1 Recordable Area R2 Individual Recording Area

Claims (14)

In the recording medium conveying mechanism in which a plurality of conveying belt mechanisms that convey the recording medium to the printing area of the recording head by the conveying belt are arranged in the conveying direction of the recording medium,
A recording medium conveying mechanism, wherein the downstream conveying belt has an upward slope with respect to the upstream conveying belt.   The recording medium conveyance mechanism according to claim 1, further comprising an angle adjustment mechanism that adjusts an upward gradient of the conveyance belt on the downstream side.   The recording medium conveyance mechanism according to claim 2, wherein the angle adjustment mechanism adjusts an upward gradient according to a print coverage.   The recording medium conveyance mechanism according to claim 2, wherein the angle adjustment mechanism adjusts an ascending slope according to a type of the recording medium.   5. The recording medium conveyance mechanism according to claim 2, wherein the angle adjustment mechanism adjusts an upward gradient according to a conveyance speed of the recording medium.   The recording medium transport mechanism according to claim 2, wherein the angle adjustment mechanism adjusts an upward gradient according to a size of the recording medium.   A guide plate for discharging the recording medium is provided on the downstream side of the most downstream conveyance belt mechanism, and the guide plate is inclined upward with respect to the conveyance belt of the most downstream conveyance belt mechanism. A recording medium transport mechanism according to any one of claims 1 to 6.   The recording medium conveyance mechanism according to claim 1, further comprising an adsorption unit that adsorbs the recording medium to the conveyance belt.   The recording medium conveyance mechanism according to claim 8, wherein the adsorption force of the adsorption unit is greater in the downstream conveyance belt mechanism than in the upstream conveyance belt mechanism. The adsorption unit is a charging unit that provides a potential difference between the conveyance belt and the recording medium, and adsorbs the recording medium to the conveyance belt;
The absolute value of the potential difference between the conveyance belt and the recording medium conveyed to the conveyance belt is larger in the conveyance belt mechanism on the downstream side than in the conveyance belt mechanism on the upstream side. 9. A recording medium transport mechanism according to 9.   The recording medium conveyance mechanism according to claim 10, wherein the charging unit is a charging roller that contacts and rotates with the conveyance belt to charge the conveyance belt.   An image forming apparatus comprising the recording medium conveyance mechanism according to claim 1.   13. The ink jet recording apparatus according to claim 12, wherein the recording unit is an ink jet recording unit that discharges and records ink droplets on the recording medium conveyed by the conveyance belt. The inkjet recording means includes
A plurality of unit heads having different ink ejection characteristics provided along the conveyance direction of the recording medium, each corresponding to a plurality of individual recording areas divided in the recording medium width direction orthogonal to the conveyance direction. A plurality of recording head sets arranged to be at different positions along the transport direction in adjacent individual recording areas;
An ink receiving means disposed opposite to the ink droplet discharge surface of the unit head and capable of receiving at least the ink discharged from the unit head;
Have
The inkjet recording apparatus according to claim 13, wherein the conveyance belt is disposed along a conveyance direction of the recording medium between the individual recording area and the individual recording area.

Images