JPH0577414A - Hot melt type ink jet recorder - Google Patents

Abstract

PURPOSE:To provide an excellent recording quality recorder without decreasing a fixing property of ink to paper by a method wherein the paper is prevented from waving in a fusion hot melt type ink jet recorder which records on a recording medium by using thermal ink which is solid at ordinary temperature and fused by heating. CONSTITUTION:When a temperature changeover switch 58 is switched, set temperature of a platen 12 is lowered. At the same time, printed caper 13 is introduced in a conveyance path B with a diverter 48 and heat-treated again with a remelt platen 52.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art Conventionally, a recording apparatus of this type, particularly a hot-melt ink jet recording apparatus which records on a recording medium using a heat-melting ink which is solid at room temperature and melts when heated, In order to achieve effective ink transfer, there is a method in which the temperature of the recording medium is raised prior to the recording operation by heating the platen that supports the recording medium at the recording position.

As shown in FIG. 4, the hot-melt type ink jet recording apparatus ejects the melted ink from a print head 70 onto a sheet 74 which is a recording medium on a platen 72 for recording. This print head 7
The carriage 76 carrying 0 is provided so as to be capable of reciprocating parallel movement on the sheet 74 supported by the platen 72 by driving a carriage motor (not shown) supported by two guide shafts 78. The paper sheet 74 is the print head 70.
From a paper feed cassette 80 provided upstream of a certain print position to a recording position by a paper feed roller 82, between the paper feed roller 82 and the print 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 drive roller 84 and the nip roller 86, which are respectively located at. When the recording is completed, the sheet 74 is conveyed to the discharged sheet collecting section 91.

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

[0005]

However, in the above-mentioned hot-melt ink jet recording apparatus, when the paper 74 that has absorbed moisture due to high humidity is used as a recording medium, the absorbed paper 74 suddenly changes. The heating evaporates the moisture from the sheet 74, causing the sheet 74 to wavy. Paper 7 when recording
The waviness in No. 4 causes deterioration of recording quality, especially when high position accuracy is required, and
There arises a problem that some convex portions of the paper 74 formed by corrugation come into contact with the print head 70 and become dirty, or the floating side edge of the paper 74 due to corrugation catches on the print head 70 and damages the paper 74 itself. It can happen. Some recording apparatuses are provided with a changeover switch for changing the temperature. If it can be predicted that the paper 74 will be wavy at the start of recording, the temperature of the platen 72 is lowered by changing over the changeover switch. The waving of the absorbed paper 74 is relieved. However, if the temperature of the platen 72 is lowered in this way, the paper sheet 74 cannot be sufficiently warmed, and therefore, there is a problem that the ink is not sufficiently fixed on the paper sheet 74. The present invention has been made to solve the above-described problems, and a recording apparatus capable of preventing the corrugation of a sheet due to heating and more effectively fixing the ink on the sheet to obtain a better recording result. Is intended to provide.

[0006]

To achieve this object, the present invention provides a hot-melt ink jet recording apparatus for recording on a recording medium using a heat-meltable ink which is solid at room 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 to preheat 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 conveyance for directly conveying the recorded recording medium to the discharged paper collecting section. The setting means includes a path, a conveyance path that detours the recorded recording medium to the position of the second heating means, and a conveyance means that has a switching means that switches these conveyance 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 construction, the first heating means heats the platen to the heating temperature set by the setting means, and the platen preheats the recording medium supported by the platen to warm the recording medium. The recording head performs recording on the medium.
Then, when the heating temperature of the platen is lowered by the setting means, the transport means bypasses the recording medium on which the recording has been performed to the transport path in which the second heating means is provided, and reheats by the second heating means. After that, the paper is conveyed to the discharged paper collecting unit.

[0008]

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

Then, as shown in FIG.
When 7 issues a recording command, the driver 18 applies a voltage to the piezoelectric element 16, and the piezoelectric element 16 is deformed into a shape projecting inward of 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, and adheres to the paper 13 supported by the platen 2 to perform recording.

1 and 2 are a sectional view and a perspective view showing the construction of a hot melt type ink jet recording apparatus. The carriage 20 equipped with the above-described inkjet head 10 is supported by two guide shafts 22 and is provided so as to be capable of reciprocating parallel movement along the platen 12 via the timing belt 26 by the drive of the carriage motor 24. .. A heater 36 for warming 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. Further, a temperature changeover switch 58 for adjusting the temperature of the platen 12 to be lowered 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 near the platen 12 facing the ink jet head 10, and a synthetic resin which is connected to the suction holes 40 and has excellent airtightness. The fan holder 46 is continuously provided on the back surface of the platen 12, and the fan 44 that is rotated by the drive of the fan motor 42 is provided at the rear end of the fan holder 46, that is, at a predetermined position opposite to the position of the platen 12. It is installed. The fan 44 is rotated by the drive of the fan motor 42, and the fan holder 4
By exhausting the air in 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 via the suction holes 40. There is.

Inkjet head 10 at the recording position
The paper 13 is conveyed in the recording position direction by the paper feed roller 30 from the paper feed cassette 28 installed upstream of the paper, and the paper 13 conveyed to the recording position is located on the upstream side and the downstream side of the recording position, respectively. Roller 32 and nip roller 3
It is nipped by 4 and the paper feed during recording is controlled.
A diverter 48 for branching the transportation path is provided downstream of the inkjet head 10. Normally, the diverter 48 is positioned so as to guide it to the transportation path A for sending the recorded paper 13 to the discharge tray 50. When the solenoid (not shown) is actuated, the deverter 48 moves to a position where the recorded sheet 13 is guided to the conveyance path B. The transport path B is provided with a remelt platen 52 for reheating and melting the recorded paper 13, and the remelt platen 52 is provided with a remelt platen 52 for heating the remelt platen 52. Heater 54
And a thermistor 38 for keeping 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 conveyed from the paper feed cassette 28 to the recording position by the paper feed roller 30. The paper 13 reaching the recording position is driven by the drive roller 32 and the nip roller 34.
It is sandwiched between the platen 12 and the platen 12 through the suction holes 40, and the platen 12 that is in close contact with the platen 12 preheats it to a predetermined temperature, and the inkjet head 10 performs recording. The recorded paper 13 on which the recording has been performed is conveyed in the downstream direction of the inkjet head 10 and guided to the conveyance path A by the deverter 48 provided at the branch point of the conveyance paths A and B, and the driving roller 33 and the nip roller 35. The paper is delivered to the paper discharge tray 50 while being sandwiched by the paper.
When the sheet 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 for guiding the recorded sheet 13 to the conveyance path B by the operation of a solenoid (not shown) and conveyed. The recorded sheet 13 guided to the path B is reheated by the remelt platen 52 sandwiched by the driving roller 31 and the nip roller 37 and set at a predetermined position on the conveyance path B, and then the sheet discharge tray 50. Sent to.

If 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 changeover 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, simultaneously with the switching, the deverter 48 moves to a position where the recorded sheet 13 is guided to the transport path B, and the recorded sheet 13 guided to the transport path B is the recorded sheet 13 due to the lowered set temperature of the platen 12. Insufficient fixing of the above ink is reheated by the remelt platen 52 on the way of the conveyance path B to complete fixing of the ink, whereby good recording results can be obtained. In the present embodiment, even if the paper 13 is plain paper, if it is a paper that has absorbed moisture, the temperature for heating the paper is lowered and the paper is transferred to the conveyance path having the reheat processing unit for the OHP sheet. Since the sheet is passed through, there is an effect that it is possible to appropriately deal with such a sheet without newly increasing the number of parts.

[0015]

As is apparent from the above description, according to the present invention, it is possible to save the paper without impairing the throughput in the normal use environment and even when the paper is used in a high humidity environment. Effective ink transfer is performed and good recording results are obtained without deteriorating recording quality due to rapid heating.

[Brief description of drawings]

FIG. 1 is a 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 showing a configuration of an inkjet head of the recording apparatus and its surroundings.

FIG. 4 is a cross-sectional view of a conventional hot melt type inkjet recording device.

[Explanation 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 Changeover Switch (Setting Means) A Conveyance Path B Transport route

Claims (1)

[Claims] 1. A hot-melt ink jet recording apparatus for recording on a recording medium using a heat-meltable ink which is solid at room temperature and melts when heated, and a recording head for recording on the recording medium and a recording head facing the recording head. A platen for supporting the recording medium, first heating means for heating the platen to preheat the recording medium, setting means for setting a heating temperature of the first heating means, and the recording means. Second heating means provided downstream of the head for reheating the recorded recording medium, a conveying path for directly conveying the recorded recording medium to the discharged paper collecting section, and the recorded recording medium to the second heating means position. A transport path for bypassing and a transport means having a switching means for switching between these transport paths, and when the heating temperature of the first heating means is lowered by the setting means, the switch is turned off. The hot-melt type ink jet recording apparatus, wherein the changing means is adapted to select and switch the conveying path having the second heating means.