JP3082352B2 - Hot melt ink jet recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording apparatus, and more particularly to a hot-melt ink jet recording apparatus.

[0002]

2. Description of the Related Art Conventionally, in a recording apparatus of this type, particularly a hot-melt ink jet recording apparatus which records on a recording medium using a heat-meltable ink which is solid at normal temperature and melts when heated, the recording medium is hardly used. In order to transfer ink effectively, a platen that supports a recording medium at a recording position is heated to raise the temperature of the recording medium prior to a recording operation.

In a hot-melt type ink jet recording apparatus, as shown in FIG. 4, a print head 70 jets molten ink onto a sheet 74 as a recording medium on a platen 72 to perform recording. This print head 7
The carriage 76 carrying the “0” is supported by two guide shafts 78 and is provided so as to be capable of reciprocating parallel movement on a sheet 74 supported by a platen 72 by driving a carriage motor (not shown). The paper 74 is the print head 70
The sheet is conveyed in the direction of the recording position by a sheet feed roller 82 from a sheet cassette 80 provided upstream of the recording position where the sheet is present, and between the sheet feeding roller 82 and the recording position where the print head 70 is located, and downstream of the print head 70 The paper feed at the recording position is controlled by the driving roller 84 and the nip roller 86 located respectively. When the recording is completed, the paper 74 is conveyed to the paper discharge collection unit 91.

A heater 88 for heating the platen 72 and a thermistor 90 for maintaining and controlling the temperature of the platen 72 are attached to the platen 72 in order to raise the temperature of the sheet 74 prior to recording. The paper 74 heated by the platen 72 maintained at the constant temperature can more effectively fix and penetrate the ink droplets ejected from the print head 70, thereby obtaining a good recording result. .

[0005]

However, in the above-described hot-melt type ink jet recording apparatus, when the paper 74 that has absorbed moisture due to high humidity is used as a recording medium, the moisture-absorbed paper 74 rapidly changes. The heating causes the water to evaporate from the paper 74, causing the paper 74 to undulate. At the time of recording, paper 7
The occurrence of undulation in 4 causes deterioration of recording quality, especially when a high degree of positional accuracy is required.
Some convexities of the paper 74 formed by the waving come into contact with the print head 70 and become dirty, and the floating side edge of the paper 74 due to the waving gets caught on the print head 70 and damages the paper 74 itself. Maybe. Some recording devices are provided with a changeover switch for changing the temperature. If it is possible to predict that the paper 74 will undulate at the start of recording, the temperature of the platen 72 is reduced by changing the changeover switch. Thus, the waving of the moisture-absorbing paper 74 is reduced. However, if the temperature of the platen 72 is lowered in this manner, the paper 74 cannot be sufficiently heated, and therefore, there is a problem that the ink is not sufficiently fixed on the paper 74. SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and a recording apparatus capable of preventing paper from waving due to heating, more effectively fixing ink on the paper, and obtaining better recording results. It is intended to provide.

[0006]

According to the present invention, there is provided a hot-melt ink jet recording apparatus for recording on a recording medium using a hot-melt ink which is solid at normal temperature and melts when heated. A recording head for recording on a medium, a platen provided to face the recording head and supporting the recording medium, first heating means for heating the platen for pre-heating the recording medium, and the first heating Setting means for setting the heating temperature of the means, second heating means provided downstream of the recording head for reheating the recorded recording medium, and transport for directly transporting the recorded recording medium to the paper discharge collection section A transport path for bypassing a path and a recorded recording medium to the position of the second heating means, and transport means having switching means for switching these transport paths. When lowering the heating temperature of the first heating means Ri, in which said switching means is to switch to select the conveying path with the second heating means.

[0007]

According to the above arrangement, the first heating means heats the platen to the heating temperature set by the setting means, and the platen preliminarily heats the recording medium supported by the platen so that the heated recording medium is heated. The recording head performs recording on the medium.
When the heating temperature of the platen is reduced by the setting unit, the conveying unit detours the recording medium on which recording has been performed to the conveying path provided with the second heating unit, and reheats the recording medium by the second heating unit. Then, the sheet is conveyed to the sheet collection section.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a hot melt type ink jet recording apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 3 is a conceptual diagram showing the configuration and operation of the ink jet head 10 and its periphery. The ink jet head 10 records on the paper 13 by ejecting the melted ink 11 onto the paper 13 on the platen 12. As shown in FIG. 3A, the inkjet head 10 is located at the center of the inkjet head 10, a nozzle 14 filled with the ink 11, and located above the nozzle 14 for heating the ink 11. A head heater 15, a piezoelectric element 16 disposed on a predetermined lower wall surface of the nozzle 14, and a platen 1 of the inkjet head 10.
2. A driver 18 for applying a voltage to the piezoelectric element 16 is provided on a side opposite to the opposite side, that is, at a rear portion of the ink jet head 10, and the driver 18 is connected to a CPU 17 for controlling each mechanism. Further, on the surface of the ink jet head 10, that is, the surface of the nozzle 14 facing the platen 12, the ink 11 does not leak out of the ink jet head 10 due to the surface tension of the ink 11.

[0009] Then, as shown in FIG.
When the recording command is issued by the driver 7, the driver 18 applies a voltage to the piezoelectric element 16, the piezoelectric element 16 is deformed into a shape protruding in the nozzle 14, and presses the ink 11 in the nozzle 14. The compressed ink 11 in the nozzle 14 is ejected from the inkjet head 10 to the outside, adheres to the paper 13 supported by the platen 2, and performs recording.

FIGS. 1 and 2 are a sectional view and a perspective view, respectively, showing the structure of a hot melt type ink jet recording apparatus. The carriage 20 on which the above-described inkjet head 10 is mounted is supported by two guide shafts 22 and provided so as to be able to reciprocate and translate along the platen 12 via the timing belt 26 by driving of the carriage motor 24. . A heater 36 for heating the platen 12 to a predetermined temperature and a thermistor 38 for detecting the temperature of the platen 12 are attached to the platen 12. A temperature changeover switch 58 for adjusting the temperature of the platen 12 to be lower is provided on the surface of the enclosure 56.

Further, in the present apparatus, a plurality of suction holes 40 are provided on the paper transport path in the vicinity of the platen 12 facing the ink jet head 10, and a synthetic resin or the like which communicates with the suction holes 40 and has excellent airtightness. A fan holder 46 is provided continuously on the back surface of the platen 12, and a fan 44 that rotates by driving the fan motor 42 is provided at a rear end of the fan holder 46, that is, at a predetermined position opposite to the platen 12 position. Installed. The drive of the fan motor 42 causes the fan 44 to rotate, and the fan holder 4
By exhausting the air inside 6 to the outside, a negative pressure is generated in the fan holder 46, and the paper 13 fed on the platen 12 comes into close contact with the platen 12 through the suction hole 40. I have.

Inkjet head 10 at recording position
The paper 13 is transported from a paper feed cassette 28 installed upstream of the printer by a paper feed roller 30 in the direction of the recording position, and the paper 13 transported to the recording position is driven upstream and downstream of the recording position, respectively. Roller 32 and nip roller 3
4 to control the paper feed during recording.
Downstream of the ink jet head 10, a deverter 48 for branching the transport path is provided. Usually, the deverter 48 is positioned so as to guide the recorded paper 13 to the transport path A for sending the recorded paper 13 to the paper discharge tray 50. When a solenoid (not shown) is operated, the diverter 48 moves to a position where the recorded paper 13 is guided to the transport path B. The transport path B is provided with a remelt platen 52 for reheating and melting the recorded paper 13. The remelt platen 52 has a remelt platen for heating the remelt platen 52. Heater 54
And a thermistor 38 for maintaining and controlling the temperature of the remelt platen 52 at a constant level.

Next, the operation of the hot melt type ink jet recording apparatus will be described with reference to FIG. When the paper 13 is plain paper, the paper 13 is transported from a paper cassette 28 to a recording position by a paper feed roller 30. The sheet 13 that has reached the recording position is driven by a driving roller 32 and a nip roller 34.
, And is adhered to the platen 12 via the suction hole 40, is heated at a predetermined temperature by the adhered platen 12 in advance, and recording is performed by the inkjet head 10. The recorded paper 13 on which recording has been performed is conveyed in the downstream direction of the ink jet head 10, guided to the conveyance path A by a deverter 48 provided at a branch point of the conveyance paths A and B, and driven by a driving roller 33 and a nip roller 35. The paper is sent out to the paper discharge tray 50 while being pinched.
When the paper 13 is an OHP sheet, after the recording is performed by the inkjet head 10 in the same manner as described above, the deverter 48 is moved to a position where the recorded paper 13 is guided to the transport path B by the operation of a solenoid (not shown). The recorded paper 13 guided to the path B is reheated by the remelt platen 52 which is nipped by the drive roller 31 and the nip roller 37 and is located at a predetermined position on the transport path B. Sent to

When the paper 13 is plain paper,
When it is possible to predict that the paper 13 will be wavy at the start of recording, the temperature switch 58 is switched in advance to lower the set temperature of the platen 12 to prevent the paper 13 from being wavy. At this time, at the same time as the switching, the deverter 48 moves to a position where the recorded paper 13 is guided to the transport path B, and the recorded paper 13 guided to the transport path B is the recorded paper 13 caused by lowering the set temperature of the platen 12. The insufficient fixing of the ink above is reheated by the remelt platen 52 on the way of the transport path B, and the fixing of the ink is completed, whereby a good recording result can be obtained. In this embodiment, even if the paper 13 is plain paper, if it is moisture-absorbing paper, the paper heating temperature is lowered and the paper is transferred to a transport path having a reheating processing unit for OHP sheets. Since the sheet is passed through, there is an effect that such a sheet can be appropriately handled without newly increasing the number of parts.

[0015]

As is apparent from the above description, according to the present invention, the paper can be used without impairing the throughput in a normal use environment and even when the paper is used in a humid environment. Effective ink transfer is performed without causing deterioration of recording quality due to rapid heating, and good recording results are obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a hot-melt ink jet recording apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view of a recording mechanism and a suction mechanism of the recording apparatus.

FIG. 3 is a conceptual diagram illustrating a configuration of an ink jet head of the recording apparatus and a periphery thereof.

FIG. 4 is a sectional view of a conventional hot-melt ink jet recording apparatus.

DESCRIPTION OF SYMBOLS 10 Inkjet head 12 Platen 34 Nip roller 36 Heater (first heating means) 48 Deverter (switching means) 52 Remelt platen 54 Remelt platen heater (second heating means) 58 Temperature switch (setting means) ) A transport route B transport route

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B41J 2/01 B41J 2/015 B41J 29/00

Claims (1)

(57) [Claims] 1. A hot-melt ink-jet recording apparatus for recording on a recording medium using a hot-melt ink which is solid at normal temperature and melts when heated, a recording head for recording on a recording medium, and a recording head facing the recording head. A platen for supporting the recording medium, first heating means for heating the platen for pre-heating the recording medium, setting means for setting the heating temperature of the first heating means, A second heating unit provided downstream of the head for reheating the recorded recording medium, a transport path for directly transporting the recorded recording medium to the paper ejection and collection unit, and moving the recorded recording medium to the second heating unit position A transport path having a detour path and a transport means having a switching means for switching these transport paths, wherein when the heating temperature of the first heating means is lowered by the setting means, the cutoff is performed. A hot-melt ink jet recording apparatus, wherein the changing means selects and switches the conveyance path having the second heating means.