JP2014162108A - Recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce temperature unevenness of a recording medium when heating a conveying path with a plurality of heaters.SOLUTION: To improve fixability of ink, a heater is provided at a conveying plate constituting a conveying path of a recording medium to heat the recording medium. A platen for supporting the recording medium in a planar shape and paper guides for adequately heating the recording medium at an upstream side and a downstream side of the platen respectively include the heaters. The platen and the paper guides have different heat capacities and heat release characteristics. Temperature differences due to regions of the platen and paper guides are prevented by an arrangement of the heaters. Thus, temperature unevenness of the recording medium can be relaxed.

Description

  The present invention relates to a recording apparatus including a heater for heating a recording medium.

  2. Description of the Related Art Recording apparatuses such as an ink jet printer that supplies ink from an ink cartridge to an ink jet recording head and ejects ink droplets from the recording head onto a recording medium to record images and characters are widely used.

  Such inkjet recording heads are widely used not only for small printers used in homes and small offices, but also for large printers capable of printing on large-sized recording media exceeding 1 meter wide. Has been.

  A solvent ink using a pigment as a coloring material and an organic solvent added to a solvent has good performance such as fixing property and light resistance to a plastic film, and is widely used for the production of printed matter for outdoor use. When the solvent ink is used, the fixing property and the drying property of the solvent ink are further improved by warming the recording medium before recording, during recording, and after recording. However, the conveyance path of the recording medium in the ink jet printer has different heat dissipation characteristics depending on the parts such as both ends and the center. As a result, a temperature difference occurs for each part of the recording medium, and due to the influence, the fixing property and the drying property differ for each part, and the image quality of the recorded image may be deteriorated. The difference is particularly noticeable in large printers.

  Therefore, as described in Patent Document 1 below, a technique is used in which a plurality of heaters are used, and a platen that supports a recording medium is subjected to heat treatment for each region, thereby improving ink fixability.

JP-A-8-207262 JP 2012-135889 A

  However, in the inkjet printer described in Patent Document 1, since the rectangular heaters are arranged in parallel along the direction intersecting the conveyance direction of the recording medium, the boundary region where the heater does not exist becomes a low temperature. It is formed along the transport direction. For this reason, since the specific portion along the conveyance direction of the recording medium continuously passes over the boundary region of the heater, the portion of the recording medium that has passed over the boundary region is appropriately heated as compared with other portions. Therefore, the temperature unevenness occurs, the ink fixing property becomes non-uniform, and the image quality deteriorates.

  The recording apparatus described in Patent Document 2 includes a preheater unit and an after heater unit that heat the recording medium on the upstream side and the downstream side in the conveyance direction of the platen and the recording medium of the platen. In these, a linear heater is folded back and forth at an end portion and arranged along the width direction. Therefore, there is no low temperature region along the conveyance direction of the recording medium. However, since the arrangement is monotonous, there arises a problem that the temperature differs depending on the portion of the portion having different heat dissipation characteristics, or the platen and the preheater portion or the afterheater portion having different heat capacities.

  Accordingly, an object of the present invention is to further reduce temperature unevenness of the recording medium when the conveyance path of the recording medium is heated.

  In order to achieve this object, an ink jet printer according to the present invention includes an ink jet head for ejecting ink, a transport means for transporting a recording medium, and the ink jet head mounted in a direction crossing the transport direction of the recording medium. A carriage that reciprocally scans, a platen that is disposed along a scanning direction of the inkjet head and that faces the inkjet that performs reciprocating scanning, and is disposed upstream of the transport direction of the platen and guides the recording medium And a pre-guide that is disposed downstream of the platen in the transport direction and guides the recording medium, wherein the platen has a groove formed on a back surface thereof, and the platen is formed in the groove. A heater wire is disposed, the platen is heated by the heater wire, and the pre- The pre-guide heater wire is disposed on the back surface of the id, the pre-guide is heated by the heater wire, and the after-guide heater wire is disposed on the back surface of the id guide. The heater wire for the platen is increased in density of wiring per unit area stepwise toward the end of the platen in the scanning direction, and the heater wire for the pre-guide is The density of the wiring per unit area gradually increases toward the scanning direction end of the guide, and the heater wire for the after guide gradually increases toward the scanning direction end of the after guide. The density of wiring per area increases and changes toward the scanning direction end of the pre-guide and the after-guide. Every stage is characterized by changes in fewer steps than the platen.

  According to the present invention, heating of the recording medium in the conveyance area of the recording medium can be made uniform, and temperature unevenness in the recording medium can be alleviated.

FIG. 1 is an external view showing an example of an ink jet printer. FIG. 2 is a diagram illustrating a platen and a paper guide. FIG. 3 is a schematic diagram illustrating an example of the arrangement of heaters.

  Hereinafter, a preferred embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a schematic diagram showing an example of the arrangement of heaters, FIG. 2 is a diagram for explaining a platen and a paper guide, and FIG. 1 is an external view showing an example of an ink jet printer. Description will be made using these.

  First, the entire inkjet printer 1 will be described. The inkjet printer 1 includes a rail 2 that extends linearly in the width direction. A carriage 3 reciprocates along the rail 2. An ink jet head is mounted on the carriage 3. The ink-jet head is mounted on the carriage 3 in correspondence with four color inks of yellow, cyan, magenta, and black for color printing. The cap 4 caps the ink jet head so that it does not dry, or periodically sucks ink from the ink jet head for maintenance. The conveyance means for conveying the recording medium includes a plurality of conveyance rollers 10 arranged along the rail 2, and conveys the recording medium by rotating the conveyance roller 10.

  The carriage 3 is connected to an endless belt 5, and the belt 5 is connected to a motor 6. The endless belt 5 is wound around a pulley installed at the end of the inkjet printer 1. By driving the motor 6, the endless belt 5 moves, and the carriage 3 also moves at the same time.

  The platen 7 is a flat plate disposed along the rail 2. The platen 7 has a plurality of suction holes on the surface, and can be fixed by sucking the conveyed recording medium through the suction holes. An after guide 8 is provided on the downstream side of the platen 7 in the conveyance direction of the recording medium. The after guide 8 guides the recording medium to be conveyed. A pre-guide 9 is provided on the downstream side of the platen 7 in the conveyance direction of the recording medium. The platen 7, the after guide 8, and the pre guide 9 are provided with heaters and can be heated. The recording medium conveyed by this heating is heated to an appropriate temperature.

  The platen 7 is a flat plate made of aluminum. The surface of the aluminum flat plate is flat and is provided with suction holes. A groove is provided on the back side, and a heater wire is embedded in the groove to heat the platen 7. Further, the after guide 8 and the pre-guide 9 are made by bending an iron plate, a heater wire is arranged on the back side, and an aluminum sheet is covered and fixed.

  The platen 7 has a thickness of about 5 to 10 mm, and the after guide 8 and the pre-guide 9 have a thickness of about 0.5 to 1.0 mm. The platen 7 has a larger heat capacity than the after-guide 8 and the pre-guide 9. When the heat capacity is large, it takes time during heating, but fluctuations in heat can be reduced. In addition, when the heat capacity is small, heating does not take time, but the fluctuation of heat increases.

  In FIG. 3, the example of the wiring of the heater wire | line of the platen 7 and the after guide 8 is shown. The heater wire 11 of the platen 7 is embedded in a groove dug in the back surface of the platen 7. The heater wires 11 are densely wired in the dense portions 12 at both ends of the platen 7. Heater wires 11 are wired in parallel at the central portion of the platen 7, and the wiring interval is wider than that of the dense portion 12, thereby forming a sparse portion 13. Further, the intermediate portion 14 is between the dense portion 12 and the sparse portion 13 and is wired with an intermediate density between them. In this way, the density of wiring per unit area is changed depending on the location. By doing so, uneven temperature is prevented.

  The heater wire 15 of the after guide 8 is covered and fixed to the back surface of the after guide 8 with an adhesive aluminum sheet. The back surface of the after guide 8 is flat, and the heater wire 15 is fixed thereto. Heater wires 15 are densely wired in dense portions 16 at both ends of the after guide 8. The central portion of the after guide 8 is constituted by a portion where the heater wire 15 is parallel and a portion which is inclined with respect to the portion. By making this slant, the length of the heater wire 15 between the dense portions 16 is shortened by about 5% compared to the case where the platen 7 is used. Further, the after guide 8 has no intermediate portion 14 like the platen 7. Here, the case where the after guide 8 and the platen 7 are the same size has been described. Further, the after-guide 8 and the pre-guide 9 are wired in the same manner as the heater wires. In this way, the density of wiring per unit area is changed depending on the location. By doing so, uneven temperature is prevented.

  The platen 7 has a large heat dissipation at both ends, and the temperature is lowered if no measures are taken. On the other hand, in order to make the temperature uniform, the amount of heat applied by making the heater wire 11 dense at the dense portion 12 is increased. And the wiring which makes the heater wire 1 sparse in steps as it goes to the center. The after-guide 8 also has a large heat dissipation at both ends, and the temperature is lowered if no measures are taken. On the other hand, in order to make the temperature uniform, the amount of heat applied by making the heater wire 15 dense at the dense portion 16 is increased. And the wiring which makes the heater wire 1 sparse in the center. The same applies to the pre-guide 9.

  The platen 7 and the after-guide 8 have different heat radiation and heat capacity, and therefore have different wirings. Since the platen 7 has a large heat capacity, it takes time to increase the heat at the end portion, so that the platen 7 is gradually increased from sparse to dense. Occasionally, since the heat capacity of the after guide 8 is small, in order to make the wiring as short as possible in the sparse portion 17, the wiring is performed obliquely without using the intermediate portion. The same applies to the pre-guide 9.

  Since the platen 7 and the after guide 8 are adjacent to each other, it is better to eliminate as much as possible the temperature difference between them. Therefore, although the density of the heater wire is almost the same at the end portion, the wiring in the middle portion and the sparse portion is made different to suppress the temperature difference. The same applies to the pre-guide 9.

  Moreover, since the platen 7 has thickness, it can heat from the inside by providing a groove | channel and putting the heater wire 11 in it, and can transfer heat suitably. Moreover, since the after guide 8 and the pre-guide 9 are the thing which curved the thin iron flat plate, the heater wire 15 is inserted | pinched with the aluminum sheet with high heat conductivity, and heat conductivity is improved.

  The present invention can be used for an ink jet printer.

1 Inkjet printer 2 Rail 3 Carriage 7 Platen 8 After guide 9 Pre-guide 11 Heater wire

Claims (4)

An inkjet head that ejects ink;
Conveying means for conveying the recording medium;
A carriage mounted with the inkjet head and reciprocatingly scanned in a direction intersecting the conveyance direction of the recording medium;
A platen disposed at a position facing the inkjet that performs the reciprocating scan along the scanning direction of the inkjet head;
A pre-guide disposed on the upstream side of the transport direction of the platen and guiding the recording medium;
A pre-guide that is disposed downstream of the platen in the transport direction and guides the recording medium;
In a recording apparatus comprising:
A groove is formed on the back surface of the platen, a heater wire for the platen is disposed in the groove, and the platen is heated by the heater wire,
The pre-guide is provided with a heater wire for the pre-guide on the back surface, and the pre-guide is heated by the heater wire,
The after guide is provided with a heater wire for the after guide on the back surface, and the after guide is heated by the heater wire,
The heater wire for the platen increases in density of wiring per unit area step by step toward the end of the platen in the scanning direction,
The heater wire for the pre-guide increases in density of wiring per unit area step by step toward the scanning direction end of the pre-guide,
The heater wire for the after guide is increased in density of wiring per unit area stepwise toward the scanning direction end of the after guide,
The recording apparatus according to claim 1, wherein the density level of the pre-guide and the after-guide that changes toward the end portion in the scanning direction is changed in fewer stages than the platen.   The recording apparatus according to claim 1, wherein a heat capacity of the platen is larger than that of the pre-guide and the after-guide.   The recording apparatus according to claim 1, wherein the platen is made of aluminum, and the pre-guide and the after-guide are made of iron.   4. The recording apparatus according to claim 1, wherein widths of regions having a high wiring density per unit area of the platen, the pre-guide, and the after-guide are equal. 5.

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