JP2007176002A - Recording device of line-head type - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recorder of line-head type which is able to prevent the bending of a conveyed recording medium without making the device body enlarged in a recording device of line-head type equipped with a head unit constituted of a plurality of recording heads. <P>SOLUTION: In the longitudinal-direction side surface of the recording head 15, two supporting strips 15a are formed as one piece. In the outside surface of the two supporting strips 15a, column-like revolving shafts 15b are formed as one piece, respectively, in parallel to the long side of the recording head 15. Bending-prevention member 16 consisting of thin-plate member of a nearly polygon with acute vertices like a throwing knife of vehicle ensiform is supported by the revolving shaft 15b. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a line head type recording apparatus that performs recording with a recording head fixed to the apparatus main body in a recording apparatus such as a facsimile, a copying machine, and a printer.

  Recording apparatuses such as facsimiles, copiers, and printers are configured to record images on recording media such as paper, cloth, and OHP sheets. However, depending on the recording method, inkjet, wire dot, and thermal It can be classified into formulas and the like. These recording methods can be further classified into a serial type in which recording is performed while the recording head scans the recording medium, and a line head type in which recording is performed by a recording head fixed to the apparatus main body.

  The line head type recording apparatus has a recording head having a recording area equal to or larger than the width of the recording medium, or a plurality of short recording heads arranged in a direction perpendicular to the conveying direction of the recording medium at a predetermined position in the apparatus body. A head unit having a recording area larger than the width of the recording medium is fixed, and the recording medium is conveyed to a predetermined recording position by a conveying means such as a conveying belt provided in the apparatus main body. One line of recording is performed collectively by the recording head or head unit having the above recording area, and then a predetermined amount is conveyed by the conveying means, and recording of the next line is performed collectively. Then, by repeating such an operation a plurality of times, the entire recording medium is recorded.

  Here, in the line head type recording apparatus, the recording medium is generally transported in a state of being attracted to a transport belt as a transport means by electrostatic adsorption or the like, but transported to a predetermined recording position. Until then, the recording medium may be bent or floated. In such a case, for example, in an ink jet recording apparatus, the recording medium comes into contact with the ink ejection surface of the recording head, the printed image flows or the nozzles are clogged, and white streaks are generated in the image. An image defect sometimes occurred.

  As a method for preventing such image defects caused by the bending of the recording medium, Patent Document 1 discloses that a shaft arranged in the width direction of the recording medium is movable in the width direction and rotated around the axis. An image defect is prevented by preventing a sheet of paper to be bent by a bending prevention member including a plurality of thin plate members arranged in a possible manner and an elastic member arranged between adjacent thin plate members. Recording devices that can do this have been proposed.

However, the head unit provided in the line head type recording apparatus has a plurality of short lengths in a direction orthogonal to the recording medium conveyance direction so that a non-printing area does not occur in the joint portion of the recording heads arranged in the width direction. In the case where the deflection preventing member described in Patent Document 1 is applied to a line head type recording apparatus provided with the head unit configured as described above. As shown in FIG. 5, an extra gap increases between the arranged recording heads 100 and the deflection preventing member 101, resulting in an increase in the size of the apparatus main body.
JP-A-7-314817

  In the present invention, in view of the above-described circumstances, in a line head type recording apparatus including a head unit configured by arranging a plurality of short recording heads, a deflection preventing member is disposed in a gap between the arranged recording heads. Accordingly, it is an object of the present invention to provide a line head type recording apparatus capable of preventing the recording medium from being bent without generating an excessive gap and without causing an increase in the size of the apparatus main body.

  In order to achieve the above object, the present invention provides a conveying means for conveying a recording medium, a plurality of head units arranged along the conveying means for recording an image over the entire width of the recording medium, and a contact arrangement on the conveying means. And a deflection preventing member for preventing deflection of the recording medium, wherein the head unit conveys a plurality of recording heads in a direction perpendicular to the conveying direction of the recording medium, and a part of the adjacent recording heads conveys the recording head. In a line head type recording apparatus that is arranged so as to overlap in the direction, at least between the adjacent head units, the deflection preventing member is provided independently for each recording head.

  According to the present invention, in the line head type recording apparatus configured as described above, the head unit is formed by arranging the recording heads in two rows in a staggered manner.

  In the line head type recording apparatus having the above-described configuration, the plurality of recording heads are all formed in the same shape.

  According to the present invention, in the line head type recording apparatus configured as described above, a support piece is integrally formed on the plurality of print heads, and the deflection preventing member is supported on the support piece. Yes.

  According to the present invention, in the line head type recording apparatus configured as described above, the bend prevention member is formed of a substantially polygonal thin plate member and is rotatably supported by the support piece.

  In the line head type recording apparatus configured as described above, the present invention is characterized in that the plurality of recording heads are of an ink jet type that performs recording on a recording medium by discharging ink from nozzles.

  According to the first configuration of the present invention, it is possible to form the width of each deflection preventing member below the width of the recording head by disposing the deflection preventing member independently for each recording head. The bending prevention member can be disposed in the gap between the recording heads. Thereby, even if it arrange | positions a bending prevention member, it becomes possible to arrange | position a several head unit so that an adjacent head unit may contact, and an apparatus main body is not enlarged. Further, the recording medium can be sufficiently prevented from being bent by being disposed at least between the adjacent head units.

  According to the second configuration of the present invention, in the line head type recording apparatus having the first configuration, the plurality of recording heads constituting the head unit are staggered in a direction orthogonal to the conveyance direction of the recording medium. By arranging in two rows, it is possible to reduce the length in the transport direction of the head unit in which a part of the adjacent recording heads are arranged so as to overlap in the transport direction, and the size of the line head type recording apparatus is reduced. be able to.

  Further, according to the third configuration of the present invention, in the line head type recording apparatus having the first or second configuration, the plurality of arranged recording heads are all formed in the same shape. There is only one type of replacement recording head that should be stored in case a malfunction occurs in the recording head of the recording unit, and the stock of replacement recording heads can be reduced.

  According to the fourth configuration of the present invention, in the line head type recording apparatus having any one of the first to third configurations, the support pieces are integrally formed on the plurality of recording heads, and the support pieces are prevented from bending. By supporting the member, it is possible to easily dispose the bending preventing member in the gap between the recording heads.

  Further, according to the fifth configuration of the present invention, in the line head type recording apparatus of the fourth configuration, the bending prevention member is formed of a substantially polygonal thin plate member, so The contact area is small and the contact area is small, so that the image recorded on the recording medium is not soiled. Further, by being rotatably supported by the support piece, it is possible to prevent the recording medium from being bent or lifted without hindering the conveyance of the recording medium conveyed on the conveying belt.

  According to the sixth configuration of the present invention, the line head type recording apparatus according to any one of the first to fifth configurations is configured to eject the ink from the nozzles provided in the recording head. By applying the recording medium to the ink jet recording apparatus, the recording medium comes into contact with the ink ejection surface of the recording head, the printed image flows or the nozzles are clogged, and the image has white streaks. Image defects such as occurrence can be prevented.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a side sectional view showing a schematic configuration of a line head type recording apparatus according to the present invention. Here, an ink jet type recording apparatus is shown as an example, but this is applied to a recording apparatus such as a wire dot type or a thermal type. Can also be applied.

  A paper feed tray 2 for storing the recording paper P is provided on the left side of the ink jet recording apparatus 1, and a paper feed tray for feeding the stored recording paper P one by one at one end of the paper feed tray. A driven roller 4 is provided which is pressed against the paper roller 3 and the paper feed roller 3 and rotates.

  A transport belt 5 is rotatably disposed in the right direction of the paper feed tray 2. The conveying belt 5 is stretched between a belt driving roller 6 disposed on the downstream side (right side in FIG. 1) and a belt roller 7 disposed on the upstream side and rotated by the belt driving roller 6 via the conveying belt 5. The recording paper P is conveyed in the direction of the arrow X by the belt driving roller 6 being driven to rotate clockwise. Here, since the belt driving roller 6 is arranged on the downstream side in the paper conveyance direction X, the paper feeding side (upper side in FIG. 1) of the conveyance belt 5 is pulled by the belt driving roller 6, so that the belt tension is applied. Therefore, the recording paper can be stably conveyed.

  A sheet made of dielectric resin is used for the conveyor belt 5, and a belt in which both ends thereof are overlapped and joined to form an endless shape, a seamless belt (seamless), or the like is preferably used.

  Further, a discharge roller 8 that discharges the recording paper P on which an image is recorded and a driven roller 9 that is driven to rotate by being pressed against the discharge roller 8 are provided on the right side of the conveyance belt 5. A tray 10 is provided. Further, four head units 11, 12, 13, and 14 described later, which are supported at a predetermined height from the conveyor belt 5, are arranged in order from the upstream side of the conveyor belt 5 above the conveyor belt 5. These head units 11 to 14 are provided corresponding to images of four different colors (cyan, magenta, yellow and black).

  The image recording operation of the ink jet recording apparatus 1 configured as described above will be described. First, the recording paper P accommodated in the paper feed tray 2 is placed on the transport belt 5 by the paper feed roller 3 and the driven roller 4. Supplied to. Then, when the conveying belt 5 rotates in the clockwise direction, the recording paper P is conveyed in the direction indicated by the arrow X, and is conveyed to a predetermined recording position below each of the head units 11 to 14.

  At this time, cyan ink is ejected onto the recording paper P by the most upstream head unit 11 at a predetermined timing, and a cyan image is recorded. Thereafter, magenta, yellow and black images are recorded by the head units 12, 13 and 14 in the same manner. These four-color images are formed with a predetermined positional relationship that is predetermined with respect to the recording paper P in order to form a predetermined full-color image.

  Then, the recording paper P on which the full-color image is recorded is separated from the transport belt 5 and is transported as it is to the paper discharge tray 10 provided outside the apparatus main body by the discharge roller 8 and the driven roller 9.

  Next, the head units 11 to 14 and the recording head 15 will be further described with reference to FIGS. 2 is a plan view of the conveyance belt 5 and the head units 11 to 14 of the ink jet recording apparatus shown in FIG. 1 as viewed from above, and FIG. 3 is a perspective view of the recording head 15.

  As shown in FIG. 2, each of the head units 11 to 14 is configured by arranging three recording heads 15 having the same shape. The recording head 15 has a rectangular plate shape, and a plurality of nozzles (not shown) are arranged in the longitudinal direction on the lower surface thereof, and ink is ejected as droplets from the nozzles. Then, the three recording heads 15 are arranged in two rows in a staggered manner in a direction orthogonal to the paper transport direction X, so that the nozzles extend over the entire width of the recording paper P in the width direction Y. Therefore, ink can be ejected over the entire width of the recording paper P in the width direction.

  Examples of the ink ejection method of the recording head 15 include a piezo method in which ink is ejected using a piezo element (not shown), and a thermal ink jet method in which bubbles are generated by a heating element and ink is ejected by applying pressure. It is done.

  The recording heads 15 are arranged so that the longitudinal ends of the adjacent recording heads 15 overlap in the paper transport direction X. When the recording heads 15 are arranged in a straight line, the image may become rough at the joints. However, the joints between the recording heads 15 are arranged by arranging the ends so as to overlap each other. In this case, ink is ejected from both of the adjacent recording heads 15, and an image can be recorded accurately even at the joint portion.

  As shown in FIG. 3, two support pieces 15 a are integrally formed on the side surface in the longitudinal direction of the recording head 15. Further, the outer side surface of the two support pieces 15 a is parallel to the long side of the recording head 15. The cylindrical rotary shaft 15b is integrally formed with each other. Further, a deflection preventing member 16 made of a substantially polygonal thin plate member having a sharp apex like a car sword-shaped shuriken is rotatably supported on the rotating shaft 15b.

  The rotation shaft 15 b is arranged at a position where the pivotally supported deflection preventing member 16 comes into contact with the conveyance belt 5, and the deflection prevention member 16 is configured to be rotated by the conveyance belt 5. Thereby, it is possible to prevent the recording paper P from being bent or lifted up without hindering the transport of the recording paper P transported on the transport belt 5. Further, since the deflection preventing member 16 has a substantially polygonal shape, it comes into contact with the recording sheet only at each vertex, and the contact area becomes very small. Therefore, the deflection of the recording sheet P can be performed without contaminating the image recorded on the recording sheet. Can be prevented.

  As described above, when a plurality of head units in which the recording heads are arranged in a staggered manner as described above are supported by supporting the deflection preventing member on the rotation shaft formed integrally with each recording head, each recording is performed. The deflection preventing member is located in the gap generated between the heads. As a result, when a deflection preventing member is conventionally provided, a useless gap is generated between the recording head and the deflection preventing member. However, in the line head type recording apparatus according to the present invention, such a gap can be eliminated. It is possible to prevent the recording paper from being bent without increasing the size of the apparatus main body.

  In addition, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the meaning of this invention. For example, in the above-described embodiment, the recording apparatus of the type that conveys the recording medium in the lateral direction from the paper feed tray has been described as an example. However, the head unit according to the present invention is provided at the bottom of the apparatus as shown in FIG. The present invention can also be applied to a type of recording apparatus that conveys a recording medium upward from a paper tray. Also, the shape, number and arrangement of the recording heads can be appropriately changed. For example, the recording heads may be arranged in a stepped manner so that a part of the recording heads overlap, and the position and number of support pieces integrally formed with the recording heads. Alternatively, the size, shape, and number of the deflection preventing members can be changed as appropriate. Furthermore, the deflection preventing member may not be directly supported by each recording head, but may be supported by the rotation shaft provided in the apparatus main body.

  The present invention relates to a line head type recording apparatus that performs recording with a recording head fixed to the apparatus main body in a recording apparatus such as a facsimile, a copying machine, and a printer.

These are side surface sectional views which show schematic structure of the line head type | mold recording device which concerns on this invention, and shows the color inkjet recording device which performs color printing as an example here. These are the top views which looked at the conveyance belt and head unit of the inkjet recording device shown in FIG. FIG. 3 is a perspective view of a recording head. These are side cross-sectional views showing another configuration of the line head type recording apparatus according to the present invention. These are plan views showing a line head type recording apparatus in which a conventional deflection preventing member is applied to a line head type recording apparatus configured by arranging a plurality of recording heads in two rows in a staggered pattern.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inkjet recording device 5 Conveyor belt 6 Belt drive roller 7 Belt roller 11, 12, 13, 14 Head unit 15 Recording head 15a Support piece 15b Rotating shaft 16 Deflection prevention member P Recording paper

Claims (6)

A conveying unit that conveys the recording medium, a plurality of head units that are fixed along the conveying unit and that record an image over the entire width of the recording medium, and are arranged in contact with the conveying unit to prevent bending of the conveyed recording medium An anti-bending member,
The head unit is a line head type recording apparatus in which a plurality of recording heads are arranged in a direction perpendicular to the conveyance direction of the recording medium so that a part of the adjacent recording heads overlaps in the conveyance direction.
The line head type recording apparatus, wherein at least the adjacent head units are provided with the anti-bending member independently for each recording head.   2. The line head type recording apparatus according to claim 1, wherein the head unit comprises the recording heads arranged in two rows in a staggered pattern.   The line head type recording apparatus according to claim 1, wherein the plurality of recording heads are all formed in the same shape.   The line according to any one of claims 1 to 3, wherein a support piece is integrally formed on the plurality of recording heads, and the support member is supported by the support piece. Head type recording device.   The line head type recording apparatus according to claim 4, wherein the deflection preventing member is formed of a substantially polygonal thin plate member and is rotatably supported by the support piece.   6. The line head type recording apparatus according to claim 1, wherein the plurality of recording heads are of an ink jet type that performs recording on a recording medium by discharging ink from nozzles.

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