JP5477042B2 - Inkjet recording device - Google Patents

Description

  The present invention relates to an ink jet recording apparatus, and more specifically, a plurality of carriages each mounting a recording head are arranged along a recording medium conveyance direction, and each carriage moves in a direction intersecting with the recording medium conveyance direction. The present invention relates to an ink jet recording apparatus that performs recording.

  Ink jet recording devices are provided with a guide rail on a support member that extends in the main scanning direction perpendicular to the recording medium conveyance direction for the purpose of increasing the printing speed, increasing the dyeing density, or applying a pretreatment agent. In addition, there is a structure in which a support member with a guide rail is installed at a predetermined interval along the recording medium conveyance direction, and a carriage on which each recording head is mounted is movably provided on each guide rail (patent) References 1, 2).

  In such an ink jet recording apparatus, after the recording along the main scanning direction is performed on the same recording medium by the recording head on the carriage disposed upstream in the conveyance direction of the recording medium, the recording medium is further disposed on the downstream side. Recording along the main scanning direction is performed by a recording head on the carriage.

JP-A-5-301340 JP 2000-282373 A

  When a carriage is attached to each of guide rails provided on a plurality of support members installed at predetermined intervals along the conveyance direction of the recording medium, there are the following problems in order to maintain print quality.

  One problem is the parallelism of movement along the main scanning direction of each carriage.

  Now, as shown in FIG. 5, the two support members 101 and 102 along the sub-scanning direction Y that is the conveyance direction of the recording medium are along the main scanning direction X that is the direction orthogonal to the conveyance direction of the recording medium. It is assumed that Here, the one end portion 102a of the downstream support member 102 is disposed by being shifted by 0.1 mm from the target position (position of the alternate long and short dash line) parallel to the upstream support member 101. When the parallelism of the movement along the main scanning direction of the carriage mounted on the members 101 and 102 is disturbed, if this inkjet recording apparatus tries to print at a resolution of 360 dpi in the conveyance direction of the recording medium, it is between one pixel of 360 dpi. Since the distance is 0.0705 mm, the landing position of the ink droplet is shifted by one pixel or more at one end 102a of the support member 102. For this reason, ink droplets do not land at an appropriate position on the one end portion 102a side of the support member 102, so that white stripes are particularly noticeable when solid printing is performed, and the print quality is greatly deteriorated.

  However, strictly defining the parallelism between the plurality of support members requires a very complicated operation, and there is a problem that it takes time to assemble the apparatus.

  Another problem is the problem of the separation distance between the carriages.

  Now, as shown in FIG. 6, it is assumed that the distance between the carriages 201 and 202 provided on the two support members installed along the conveyance direction of the recording medium is 500 mm. Here, the conveyance of the recording medium is bent, and the conveyance direction Y ′ is not perpendicular to the main scanning direction X which is the scanning direction of the carriages 201 and 202, and an error of 0.1 ° is generated (main When the sub-scanning direction Y ′ is 90.1 ° with respect to the scanning direction X, the recording head on the downstream carriage 202 is positioned at the same position as the landing position d1 printed by the recording head on the upstream carriage 201. Even if printing is performed at this time, the recording medium cannot be printed at the same landing position d because of a deviation in the conveyance direction of the recording medium, and the landing position d2 by the recording head on the carriage 202 on the downstream side is mainly the recording medium. Even if the sheet is transported with a deviation of 0.1 ° with respect to the scanning direction X, the landing position is shifted by 0.87 mm. When the resolution in the main scanning direction X is 540 dpi, the distance between the pixels is 0.047 mm, so that the amount of deviation is 18 pixels.

  Inkjet recording devices ideally transport the recording medium straight so that no deviation occurs during transportation. Actually, however, the recording medium is transported in the width direction due to various factors such as mechanical errors in the transportation means. In many cases, a slight deviation occurs. In the above case, if the separation distance between the carriages 201 and 202 is halved to 250 mm, even if the conveyance angle error is the same 0.1 °, the landing position deviation can be suppressed to 0.44 mm. Therefore, a shorter separation distance between adjacent carriages is advantageous because the distance of the printing area along the recording medium conveyance direction can be shortened and landing position deviation can be suppressed accordingly.

  In the case of an ink jet recording apparatus in which a support member with a guide rail and a carriage are provided in a one-to-one correspondence, it is preferable to increase the distance between the carriages from the viewpoints of maintenance and assembly. However, if the distance between the carriages is increased, it becomes difficult to suppress landing position deviation as described above, and it becomes difficult to obtain a high-quality image.

  In order to obtain a high-quality image, it may be possible to reduce the distance between the carriages at the expense of maintainability and assemblability, but even in this case, the support member is still required for each carriage, and the cost is much higher. There is such a problem.

  Accordingly, the problem of the present invention is that it is not necessary to adjust the parallelism of a plurality of carriages arranged along the conveyance direction of the recording medium, the distance between adjacent carriages can be shortened, and the cost can be reduced. It is to provide an ink jet recording apparatus.

  Other problems of the present invention will become apparent from the following description.

  The above problems are solved by the following inventions.

According to a first aspect of the present invention, a first carriage and a second carriage, each mounted with a recording head for ejecting ink, are arranged in order along the conveyance direction of the recording medium, and the first carriage and the second carriage are arranged. a the carriage is moved in a direction intersecting the transport direction of each of the recording medium by an ink jet recording apparatus for recording,
A support member constructed in a direction crossing the conveyance direction of the recording medium;
A guide rail that is fixed to the support member and is formed along a direction in which the support member is installed, and that holds the first carriage and the second carriage;
The first carriage and the second carriage pass through the guide rail with respect to the support member disposed at a position sandwiched between the first carriage and the second carriage in the conveyance direction of the recording medium. The parallelism between the first carriage and the second carriage in a direction intersecting the conveyance direction of the recording medium is defined by the support member. Inkjet recording apparatus.

  According to a second aspect of the present invention, a drying unit is provided between the first carriage and the second carriage and below the support member for drying the ink ejected onto the recording medium. The inkjet recording apparatus according to claim 1.

  According to a third aspect of the present invention, the guide rail includes a first guide rail that moves the first carriage, and a second guide rail that moves the second carriage. Item 3. The ink jet recording apparatus according to Item 1 or 2.

  According to a fourth aspect of the present invention, there is provided a common drive source for moving the first carriage and the second carriage along the first guide rail and the second guide rail, respectively. The inkjet recording apparatus according to claim 3.

  According to a fifth aspect of the present invention, the first carriage and the second carriage are integrally connected by a connecting member, and the common drive source is connected to the first carriage via the connecting member. 5. The ink jet recording apparatus according to claim 4, wherein the carriage and the second carriage are moved along the first guide rail and the second guide rail, respectively.

  According to the present invention, there is no need to adjust the parallelism of a plurality of carriages arranged along the conveyance direction of a recording medium, the distance between adjacent carriages can be shortened, and the cost can be reduced. An apparatus can be provided.

The side view which shows the recording part of the inkjet recording device which concerns on this invention Partial perspective view showing a recording unit The side view which shows the other aspect of the recording part of the inkjet recording device which concerns on this invention. The side view which shows the recording part of the inkjet recording device which concerns on the other aspect of this invention. The figure explaining the problem of the conventional inkjet recording device The figure explaining the problem of the conventional inkjet recording device

  In the ink jet recording apparatus according to the present invention, a first carriage and a second carriage, each of which is mounted with a recording head for ejecting ink, are sequentially arranged along the recording medium conveyance direction (sub-scanning direction). The first carriage and the second carriage perform recording by moving along a guide rail installed in a direction (main scanning direction) intersecting the conveyance direction of the recording medium.

  In the present invention, the guide rail for moving the first carriage is fixed to a single support member constructed along a direction (main scanning direction) intersecting the recording medium conveyance direction, and the first carriage and the second carriage are fixed. The carriage is arranged with this single support member in common with both.

  As a result, the parallelism between the first carriage and the second carriage is defined by the straight advance accuracy of the single support member, and the parallelism between the first carriage and the second carriage. There is no need to match. This eliminates the troublesome work of adjusting the parallelism between the carriages when assembling the apparatus. For this reason, it is possible to simplify the assembling operation of the apparatus without deteriorating the print quality due to the disturbance of the parallelism between the upstream and downstream carriages.

  Furthermore, since the first carriage and the second carriage have a common support member, the distance between the carriages can be made as short as possible compared to the case where the support members are provided corresponding to each carriage on a one-to-one basis. . For this reason, it is possible to suppress a decrease in print quality due to a landing position shift between the upstream recording head and the downstream recording head due to a conveyance shift in the main scanning direction of the recording medium as much as possible. In addition, since the number of support members for the two carriages is reduced, the cost can be reduced accordingly.

  In the present invention, the first carriage and the second carriage mean a carriage arranged on the upstream side in the recording medium conveyance direction and the other on the downstream side in the recording medium conveyance direction with a single support member therebetween. To do.

  Next, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a side view showing a recording section of an ink jet recording apparatus according to the present invention, and FIG. 2 is a partial perspective view showing the recording section.

  The inkjet recording apparatus 1 prints on a recording unit P that is transported by the transport unit 2 above the transport unit 2 and a transport unit 2 that moves the recording medium P along the sub-scanning direction Y that is the transport direction. And a recording unit 3 for performing.

  In the transport unit 2, a transport belt 22 is bridged between transport rollers 21, 21 arranged at a predetermined interval along the sub-scanning direction Y, and one transport roller 21 has a transport motor (not shown). When the driving force is transmitted, the conveying belt 22 is rotated along the sub-scanning direction Y indicated by an arrow in the drawing, and the recording medium P on the conveying belt 22 is moved in the sub-scanning direction Y.

  In the recording unit 3, a first carriage 4 </ b> A and a second carriage 4 </ b> B are arranged in order from the upstream side along the conveyance direction of the recording medium P above the conveyance belt 22.

  Each of the carriages 4A and 4B has bottom plate portions 41A and 41B on which the recording heads 5A and 5B are mounted, respectively, and back plate portions 42A and 42B standing from one end of the bottom plate portions 41A and 41B. The back plate portions 42A and 42B are arranged so as to face each other. The recording heads 5A and 5B mounted on the carriages 4A and 4B can be configured by a plurality of recording heads that discharge ink of each color such as YMCK, for example.

  Between the first carriage 4A and the second carriage 4B, one support stay 6 which is a support member common to the carriages 4A and 4B is connected to the sub-scanning direction Y which is the conveyance direction of the recording medium P. It is constructed along the orthogonal main scanning direction X. The support stay 6 has a length over the width of the recording medium P on the transport belt 22.

  A first guide rail 61A and a second guide rail 61B are fixed along the support stay 6 on each side surface of the single support stay 6 on the upstream side and the downstream side in the conveyance direction of the recording medium P, respectively. ing. The guide rails 61A and 61B are engaged with slide blocks 43A and 43B projecting from the back plate portions 42A and 42B of the carriages 4A and 4B. The carriages 4A and 4B are engaged with the guide rails 61A and 61B, respectively. It can be reciprocated in the main scanning direction X along 61B.

  The first carriage 4A and the second carriage 4B are integrally connected by a connecting plate portion 44 at the upper end portions of the back plate portions 42A and 42B. For this reason, the first carriage 4A and the second carriage 4B are integrally moved back and forth along the main scanning direction X along the support stay 6.

  Above the support stay 6, an endless belt 7, which is a driving force transmission means, is disposed along the support stay 6. The endless belt 7 is bridged between a pair of pulleys 71, and a driving force from a driving motor 8 that is a driving source is transmitted to one pulley 71.

  The connecting plate portion 44 is fixed to the endless belt 7. Accordingly, when the endless belt 7 is rotationally driven by the drive motor 8, the first carriage 4 </ b> A and the second carriage 4 </ b> B reciprocate integrally along the support stay 6.

  In the inkjet recording apparatus 1, the recording head 5A on the first carriage 4A disposed on the upstream side in the process in which the recording medium P is transported in the sub-scanning direction Y by the transport belt 22 When the recording medium P is conveyed and positioned immediately below the second carriage 4B on the downstream side, the recording head 5B on the second carriage 4B is moved to the recording head 5A. The desired printing is performed by further ejecting ink onto the pattern printed by.

  In the inkjet recording apparatus 1 shown in the present embodiment, the first carriage 4A and the second carriage 4B arranged along the conveyance direction of the recording medium P move along a single support stay 6. Thus, the parallelism between the carriages 4A and 4B is defined by the straight advance accuracy of the support stay 6. Therefore, it is not necessary to match the parallelism between the carriages 4A and 4B, and the troublesome work of adjusting the parallelism between the carriages when assembling the apparatus is eliminated. For this reason, it is possible to simplify the assembling operation of the apparatus without deteriorating the print quality due to the disturbance of the parallelism between the upstream and downstream carriages.

  Further, the first carriage 4A and the second carriage 4B are mounted on guide rails 7A and 7B provided along a single support stay 6, so that the first carriage 4A can be used as a recording head. 5A faces the upstream side in the transport direction of the recording medium P with the back plate portion 42A in the back, and the other second carriage 4B is downstream in the transport direction of the recording medium P with the recording head 5B facing the back plate portion 42B. Facing. For this reason, the attaching / detaching operation and the maintenance operation of the recording head 5A or 5B with respect to each carriage 4A or 4B can be performed from the upstream side and the downstream side in the conveyance direction of the recording medium P, respectively, and the other carriage 4B or 4A or the support stay 6 can be performed. Will not get in the way.

  As a result, the ink jet recording apparatus 1 shown in the present embodiment has a recording medium P of the recording unit 3 extending between the carriages 4A and 4B, as compared with the case where a support stay is provided for each carriage on a one-to-one basis. The length L1 along the transport direction can be shortened as much as possible. For this reason, it is possible to suppress as much as possible a decrease in print quality due to a landing position shift between the upstream recording head 5A and the downstream recording head 5B due to a conveyance shift in the main scanning direction X of the recording medium P.

  In addition, since the inkjet recording apparatus 1 shown in the present embodiment is provided with only one support stay 6 for the carriages 4A and 4B adjacent to the upstream side and the downstream side in the conveyance direction of the recording medium P, the number of parts is reduced. The cost can be reduced by reducing the cost.

  Furthermore, in the ink jet recording apparatus 1 shown in the present embodiment, the first carriage 4A and the second carriage 4B are integrated by a connecting plate portion 44 that is a connecting member, and these are moved together by a single drive motor 8. Therefore, the number of drive motors can be reduced with respect to the number of carriages, and accordingly, the apparatus cost can be reduced, the weight can be reduced, and the drive motor space can be reduced.

  By the way, when the first carriage 4A and the second carriage 4B are arranged along the conveyance direction of the recording medium P, after the printing is performed by the recording head 5A on the upstream first carriage 4A, immediately downstream When printing is performed by the recording head 5B on the second carriage 4B, the ink oozes on the recording medium P depending on the type of ink or the type of the recording medium P, which causes a decrease in printing quality. For this reason, it is preferable to arrange the drying means 9 between the carriages 4A and 4B as shown in FIG.

  The drying means 9 is arranged below the support stay 6 with a length that is equal to or greater than the width of the recording medium P on the conveyor belt 22, as with the support stay 6. Here, an example using a halogen heater is shown, but the specific mode of the drying means is not limited. Alternatively, wind (warm air) that does not affect printing may be blown. The drying means 9 is attached to and supported by the lower portion of the support stay 6 by support means (not shown). It is also preferable that the support means can adjust the distance from the recording medium P by making the height position of the drying means 9 adjustable.

  Further, in place of or in addition to the drying means 9, the recording medium P positioned below the support stay 6 is warmed from the back side of the recording medium P by heating the conveying belt 22, and the ink is supplied. It is also possible to employ a configuration for drying.

  FIG. 4 is a side view showing a recording unit of an ink jet recording apparatus according to another aspect of the present invention. The parts with the same reference numerals as those in FIG. 1 and FIG.

  In this aspect, the first carriage 4A and the second carriage 4B are provided on the upstream side and the downstream side, respectively, in the conveyance direction of the recording medium with respect to the support stay 6 that is a single support member, and these are integrated. Although it is the same as the above-described aspect in that it can move along the support stay 6, the guide rail is also composed of a single guide rail 61 for the first carriage 4A and the second carriage 4B. The movement of the carriages 4A and 4B is commonly guided by the single guide rail 61.

  The single guide rail 61 is provided along the upper end of the support stay 6. On the other hand, a single slide block 43 is provided on the lower surface of the connecting plate portion 44 between the first carriage 4A and the second carriage 4B facing the upper surface of the guide rail 61. By engaging 43 with the guide rail 61, the first carriage 4 </ b> A and the second carriage 4 </ b> B are integrally movable along the guide rail 61.

  Accordingly, the first carriage 4A and the second carriage 4B are configured to move in the main scanning direction along the single guide rail 61 at the portion of the connecting plate portion 44 that is the central portion. Since the guide rail 61 coincides with the load applied to the first carriage 4A and the second carriage 4B, the fulcrum of the support stay 6 is the same as the first carriage 4A. Compared with the above-described aspect in which the first carriage rail 43B and the second guide rail 43B are used by the second carriage 4B, smoother movement can be realized.

  Further, since it is only necessary to provide a single guide rail 61 for the first carriage 4A and the second carriage 4B, the number of guide rails relative to the number of carriages can be reduced, and the cost can be reduced accordingly.

  Furthermore, since the number of guide rails is reduced, the number of assembling steps can be reduced, and the labor and time required for assembling can be reduced.

  Reference numerals 45 </ b> A and 45 </ b> B in FIG. 4 are tilt prevention members that protrude from the back plate portion 42 </ b> A of the first carriage 4 </ b> A and the back plate portion 42 </ b> B of the second carriage 4 </ b> B toward the support stay 6. The inclination preventing members 45A and 45B protrude from the back plate portions 42A and 42B toward the side surfaces 6a and 6b facing the support stay 6, and their tips are slidable with respect to the side surfaces 6a and 6b. It is in contact.

  Thus, when the first carriage 4A and the second carriage 4B are moved with the single guide rail 61 as a fulcrum, the first carriage 4A and the second carriage 4B are upstream or downstream in the conveyance direction of the recording medium. The inclination prevention members 45A and 45B are prevented from sliding while being in contact with the side surfaces 6a and 6b of the support stay 6. Therefore, even if the guide rail is a single guide rail 61 common to the carriages 4A and 4B, the first carriage 4A and the second carriage 4B can be smoothly moved without being inclined.

  The inclination preventing members 45A and 45B are made of a synthetic resin block having a good sliding property such as POM (polyacetal resin), and are also slidable at the tips contacting the side surfaces 6a and 6b of the support stay 6. In consideration of the above, a rotating body such as a rolling bearing may be provided.

  In the embodiment shown in FIG. 4, it is needless to say that the drying means 9 similar to the embodiment shown in FIG. 3 can be provided.

1: Inkjet recording device 2: Conveying unit 21: Conveying roller 22: Conveying belt 3: Recording unit 4A: First carriage 4B: Second carriage 41A, 41B: Bottom plate portion 42A, 42B: Back plate portion 43, 43A, 43B: Slide block 44: Connecting plate portion 45A, 45B: Anti-tilt member 5A, 5B: Recording head 6: Support stay (support member)
6a, 6b: Side surface 61: Guide rail 61A: First guide rail 61B: Second guide rail 7: Endless belt 71: Pulley 8: Drive motor (drive source)
9: Drying means P: Recording medium

Claims (5)

A first carriage and a second carriage, each mounted with a recording head for ejecting ink, are sequentially arranged along the recording medium conveyance direction, and the first carriage and the second carriage are respectively arranged on the recording medium. an inkjet recording apparatus which performs recording by moving in a direction intersecting the transport direction,
A support member constructed in a direction crossing the conveyance direction of the recording medium;
A guide rail that is fixed to the support member and is formed along a direction in which the support member is installed, and that holds the first carriage and the second carriage;
The first carriage and the second carriage pass through the guide rail with respect to the support member disposed at a position sandwiched between the first carriage and the second carriage in the conveyance direction of the recording medium. The parallelism between the first carriage and the second carriage in a direction intersecting the conveyance direction of the recording medium is defined by the support member. Inkjet recording apparatus.   2. A drying unit for drying ink ejected onto the recording medium is provided between the first carriage and the second carriage and below the support member. The ink jet recording apparatus described.   3. The inkjet recording according to claim 1, wherein the guide rail includes a first guide rail that moves the first carriage and a second guide rail that moves the second carriage. apparatus.   4. The inkjet according to claim 3, further comprising a common drive source for moving the first carriage and the second carriage along the first guide rail and the second guide rail, respectively. Recording device.   The first carriage and the second carriage are integrally connected by a connecting member, and the common drive source is configured to connect the first carriage and the second carriage via the connecting member. 5. The ink jet recording apparatus according to claim 4, wherein the ink jet recording apparatus is moved along the first guide rail and the second guide rail, respectively.

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