JPH07277540A - Paper feed cassette and thermal printer - Google Patents

Abstract

PURPOSE:To prevent the change of coloring characteristic by restraining the temperature rise of record paper by making a paper feed cassette main body double structure, cutting off heat from a printer main body. CONSTITUTION:A paper feed cassette 10 is composed of the double structure of an inner cassette main body 12 to house a heat sensing record paper sheet 11 and an outer cassette 13 to house turnably this inner cassette main body 12. An adiabatic air layer is constituted by forming projecting stripe portions 13a-13e at the inner wall of the outer cassette main body 13 and forming an opening between the inner and outer main bodies 12, 13. A lift lever 21 that pushes up the inner cassette main body 12 at the time of paper feed and presses a heat sensing record paper sheet 11 against a paper feed roller 19 is provided at a cassette loading chamber 18. Also, the paper feed cassette 10 may be cooled by fitting a cooling fan to the inside of the cassette loading chamber 18 on the bottom plate outer surface of the cassette main body.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feed cassette for accommodating thermal recording paper and a thermal printer using the same.

[0002]

2. Description of the Related Art In a thermal printer, a thermal recording paper having at least one thermosensitive coloring layer formed on one side thereof is used. After thermal recording is performed on this thermosensitive coloring layer by a thermal head, the coloring ability is lost by irradiating ultraviolet rays in a wavelength range peculiar to the thermosensitive coloring layer with a fluorescent lamp for optical fixing. Such thermal recording papers are stored in a paper feed cassette in a stacked state, and the paper feed cassette is loaded into the cassette loading chamber of the thermal printer.

[0003]

When performing continuous printing with the above thermal printer, since the fluorescent lamp for optical fixing is continuously turned on, the temperature inside the printer body rises due to the heat of the fluorescent lamp. This heat is transmitted through the frame of the printer body and raises the temperature in the cassette loading chamber,
The temperature of the paper feed cassette loaded in the cassette loading chamber is raised. As a result, the thermosensitive recording paper stored in the paper feeding cassette is warmed, and the water content of the thermosensitive coloring layer of the thermosensitive recording paper is reduced. Since the coloring property of the thermosensitive coloring layer changes depending on the water content, the thermosensitive recording paper whose water content of the thermosensitive coloring layer has decreased cannot be colored to a desired density even if heat energy according to the image data is applied. .

It is an object of the present invention to provide a paper feed cassette and a thermal printer in which the temperature rise of the thermal recording paper is prevented.

[0005]

In order to achieve the above object, the paper feed cassette of the present invention has a double body structure of the cassette body of the paper feed cassette. Also, a cooling fan is attached to the cassette body so that cooling air is blown to the cassette body.

In the thermal printer of the present invention, a cooling fan is attached to a cassette loading chamber for loading a paper feeding cassette,
Cooling air is blown to the paper feeding cassette in the cassette loading chamber.

[0007]

Since the cassette main body of the paper feed cassette has a double structure, heat from the printer main body is blocked, and the temperature rise of the thermal recording paper stored in the cassette main body is prevented. Therefore, the water content of the thermosensitive coloring layer does not decrease and the coloring characteristics do not change.

Further, since the cooling fan is attached to the cassette body and the cooling air is blown to the cassette body, the temperature rise of the thermosensitive recording paper contained in the cassette body is prevented. Therefore, the water content of the thermosensitive coloring layer does not decrease and the coloring characteristics do not change.

Further, since a cooling fan is attached to the cassette loading chamber to blow cooling air to the paper feeding cassette loaded in the cassette loading chamber, the temperature rise of the thermal recording paper stored in the cassette body is prevented. It Therefore, the water content of the thermosensitive coloring layer does not decrease and the coloring characteristics do not change.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, a paper feed cassette 10 has a dual structure including an inner cassette body 12 for accommodating laminated thermal recording papers 11 and an outer cassette body 13 for accommodating the inner cassette body 12 rotatably. Has become. Protrusions 13a to 13e are formed on the inner wall of the outer cassette body 13, and a gap 1 is formed between the inner cassette body 12 and the outer cassette body 13.
5 is formed. The air layer in the gap 15 can block heat from the outside. The thermosensitive recording paper 11 is, for example, a monochromatic thermosensitive recording paper in which a thermosensitive coloring layer of one color and a protective layer are layered on a PET support.

A cassette loading chamber 18 for loading the paper feed cassette 10 is provided with a lift lever 21 for pushing up the inner cassette body 12 to press the thermal recording paper 11 against the paper feed roller 19 at the time of paper feeding. When the sheet cassette 10 is inserted into the cassette loading chamber 18, the lift lever 21 is inserted between the outer surface of the bottom plate of the inner cassette body 12 and the inner surface of the bottom plate of the outer cassette body 13 through the hole formed in the outer cassette body 13. To be done. The lift lever 21 is driven by the pusher 22.

When the paper is fed, the thermal recording paper 11 is fed by the paper feed roller 19
When pressed against, the first thermal recording paper 11 from above is pushed toward the paper feed path 24. The thermosensitive recording paper 11 is sent to the printing unit 25 through the paper feed path 24. The print unit 25 is, for example, a monochrome line printer that relatively moves the thermal recording paper 11 in the sub-scanning direction and records the thermal recording paper 11. The printer unit 25 is provided with, for example, a platen drum. On the outer periphery of the platen drum, a thermal head is arranged at the thermal recording position of the thermal recording paper 11, and an optical fixing device is arranged downstream thereof. In the thermal head, a large number of heating elements are arranged in a line in the main scanning direction, and each heating element generates heat energy according to the density of the pixel.

The thermal recording paper 11 has its front end fixed to the peripheral surface of the platen drum via a clamper. As the platen drum rotates, the thermosensitive recording paper 11 is wound around the peripheral surface of the platen drum, and when it reaches the recording position, a thermal image is thermally recorded by the thermal head. After that, the thermal recording paper 11 is irradiated with ultraviolet rays by the optical fixing device, and the thermal coloring layer is optically fixed. The thermally fixed recording paper 11 on which the light has been fixed is ejected with the front end fixed.

When printing is continuously performed by the thermal printer having such a configuration, the lighting time of the optical fixing device becomes long and the temperature of the printing section 25 rises. The heat from the printing unit 25 is also transmitted to the cassette loading chamber 18 via the frame of the printer body, etc., and the temperature of the cassette loading chamber 18 rises. The outer cassette 13 is heated as the temperature of the cassette loading chamber 18 rises, but the temperature of the inner cassette body 12 hardly rises due to the air layer in the gap 15. Therefore, since the thermosensitive recording paper 11 stored in the inner cassette body 12 is not heated, the coloring characteristic of the thermosensitive coloring layer does not change.

In FIG. 2, the sheet feeding cassette 30 is configured such that a cooling fan 33 is attached to the outer surface of the bottom plate 32 of the cassette body 31 to cool the sheet feeding cassette 30. A large number of vent holes 34 a are provided in the cassette loading chamber 34 at a position facing the cooling fan 33 to take in outside air into the cassette loading chamber 34. A temperature sensor 35 is attached to the bottom plate 32 of the cassette body 31 to detect the temperature inside the cassette body 31. Based on this temperature information, the cooling fan 3 is controlled so that the temperature inside the cassette body 31 is maintained constant.
3 is controlled.

The drive control of the cooling fan 33 is performed on the printer body side of the thermal printer. Therefore, the front plate 36 of the cassette body 31 is provided with the respective connectors 37 for the cooling fan 33 and the temperature sensor 35, and the corresponding connectors 38 are provided in the cassette loading chamber 34. When the paper feed cassette 30 is inserted into the cassette loading chamber 34, the connectors 37 and 38 are connected, and the cooling fan 33 and the temperature sensor 35 of the paper feed cassette 30 are connected to the control unit 39 in the printer body via these. The control unit 39 processes the temperature information of the temperature sensor 35 and controls the power supply to the cooling fan 33. Even if the use of the thermal printer is suspended for a while, the temperature inside the cassette body 31 is kept constant unless the power source of the printer body is turned off while the paper feed cassette 30 is inserted into the cassette loading chamber 34. Since the ink is dripping, the color developing characteristics of the thermosensitive coloring layer of the thermosensitive recording paper 11 do not change, and it is not necessary to readjust the print density.

In FIG. 3, the thermal printer 40 is
A cooling fan 42 is attached to the lower portion of the cassette loading chamber 41 so that the sheet feeding cassette 43 loaded in the cassette loading chamber 41 is cooled from the bottom side. In order to efficiently take in cooling air from the cooling fan 42 into the cassette body 44 of the sheet feeding cassette 43, the bottom plate 45 of the cassette body 44 is formed with a large number of ventilation holes 45a. A large number of ventilation holes 46 for taking in outside air are formed behind the cooling fan 42.

A temperature sensor 47 is attached to the upper part of the cassette loading chamber 41, and the driving of the cooling fan 42 is controlled based on the temperature information output from the temperature sensor 47. As a result, the temperature of the thermosensitive recording paper 11 housed in the cassette body 44 is maintained constant, and the color forming characteristics of the thermosensitive coloring layer of the thermosensitive recording paper 11 do not change during continuous printing. Further, even if the use of the thermal printer is suspended for a while, the temperature in the cassette body 44 is kept constant unless the power of the printer body is turned off, so that it is not necessary to readjust the print density.

The temperature sensors 35 and 47 may be humidity sensors, and the cooling fan may be controlled based on the humidity information to maintain the humidity in the cassette body constant.

In the embodiment described above, the present invention is applied to a monochrome thermal printer, but it goes without saying that it may be applied to a color thermal printer. In this case, a color thermosensitive recording material in which thermosensitive coloring layers of three colors are sequentially laminated is used, and two kinds of lamps having different wavelengths of ultraviolet rays are arranged in the printing section, and the upper 2
The two thermosensitive coloring layers are photo-fixed after thermal recording. Further, the printing unit is an example of a line printer that relatively moves the thermal recording paper in the sub-scanning direction for recording, but the present invention is not limited to this, and the two-dimensional relative movement is performed. It can also be applied to a serial printer for recording.

[0021]

As described above, according to the paper feed cassette of the present invention, since the cassette body has a double structure, the heat of the optical fixing device is shut off, and the temperature of the thermal recording paper rises even during continuous printing. Is prevented. Therefore, since the water content of the thermosensitive color developing layer of the thermosensitive recording paper does not decrease, the color developing characteristics of the thermosensitive color developing layer do not change. Further, since the cassette body is provided with the cooling fan, the temperature rise of the thermal recording paper is prevented even during continuous printing, and the same effect can be obtained.
Further, according to the thermal printer of the present invention, since the cooling fan is provided in the cassette loading chamber, it is possible to prevent the temperature rise of the sheet feeding cassette loaded in the cassette loading chamber,
Even during continuous printing, the color developing characteristics of the thermosensitive coloring layer of the thermosensitive recording paper can be kept constant. Even if the use of the thermal printer is suspended for a while, the power of the printer body is turned off.
Unless it is set to F, the temperature inside the cassette body is kept constant, so that it is not necessary to readjust the print density.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a state in which a paper feed cassette having a double cassette body is loaded in a cassette loading chamber of a thermal printer.

FIG. 2 is an explanatory diagram showing a state in which a paper feed cassette having a cassette body provided with a cooling fan is loaded in a cassette loading chamber of a thermal printer.

FIG. 3 is a schematic explanatory view of a main part of the thermal printer showing a state in which a paper feed cassette is loaded in a cassette loading chamber provided with a cooling fan.

[Explanation of reference numerals] 10,30,43 Paper feed cassette 11 Thermal recording paper 12 Inner cassette body 13 Outer cassette body 18,34,41 Cassette loading chamber 31,44 Cassette body 33,42 Cooling fan 34a, 45a Vent hole 35, 47 Temperature Sensor 39 Control Unit 40 Thermal Printer

Claims (3)

[Claims] 1. A paper feed cassette in which a thermosensitive recording paper is placed, wherein the cassette body has a double structure. 2. A paper feed cassette in which a thermosensitive recording paper is placed, wherein a cooling fan is attached to the cassette body, and cooling air is blown to the cassette body. 3. A thermal printer characterized in that a cooling fan is attached to a cassette loading chamber for loading a paper feeding cassette, and cooling air is blown to the paper feeding cassette in the cassette loading chamber.