JPH04151659A - Thermal fixing device - Google Patents

Abstract

PURPOSE:To obtain the thermal fixing device which allows the complete sepn. of a medium to be recorded from a thermal fixing belt and does not discharge odorous gases to the outside by disposing a cooling fan which blows out air toward the thermal fixing belt in the direction opposite from the transporting direction of the thermal fixing belt between a pressing roller and a paper discharge port. CONSTITUTION:The medium to be recorded is transported according to the rotation of the thermal fixing belt 55 and the images formed on this medium to be recorded are heated and fixed when the thermal fixing belt 55 rotates. The medium to be recorded is cooled by the cooling fan 63 provided between the pressing roller 58 and a discharge port 34 and the medium to be recorded is completely separated from the thermal fixing belt 55. Since the blowing out direction of the cooling fan 63 is set opposite from the transporting direction of the medium to be recorded, the odorous gases are not directly discharged from the paper discharge port 35 to the outside. The thermal fixing device which can separate the medium to be recorded completely from the thermal fixing belt and does not discharge the odorous gases generated at the time of heating the medium to be recorded directly from the paper discharge port 35 is obtd. in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a thermal fixing device that pressurizes and heats an image formed on a recording medium to fix the image on the recording medium.

[Prior Art] In a conventional heat fixing device of this type, for example, a heat fixing belt is stretched between a heat roller and a tensioning roller, and a heat roller is applied via the heat fixing belt. The pressure roller is pressed. The recording medium is conveyed as the thermal fixing belt rotates, and the recording medium is sandwiched between the thermal fixing belt and the pressure roller, and is pressed and heated to fix the image on the recording medium. After fixing, the paper is discharged from the paper discharge port.

[Problems to be Solved by the Invention] However, in this belt-type heat fixing device, the heat fixing belt and the recording medium are brought into pressure contact and heated, so the recording medium is conveyed while being stuck to the heat fixing belt. If the heated recording medium is not cooled sufficiently, there is a problem in that the recording medium is transported without being separated from the heat fixing belt, resulting in a state in which transport is impossible. For this reason, some devices are equipped with a cooling fan that actively cools down the heated recording medium. However, if the blowing direction of this cooling fan is the same as the conveyance direction of the recording medium, there is a problem in that the odorous gas generated when the recording medium is heated by the heat roller is exhausted outside the apparatus from the paper ejection port. There was a point.

The present invention has been made in order to solve the above-mentioned problems, and provides a heat fixing device that can completely separate a recording medium from a heat fixing belt and does not directly exhaust odor gas to the outside. The purpose is to

[Means for Solving the Problems] In order to achieve this object, the present invention includes a pair of rollers disposed a predetermined distance apart, a heat fixing belt stretched between the pair of rollers, and a heat fixing belt stretched between the pair of rollers. , comprising a heat generating means disposed between a pair of rollers, and a pressure roller that presses against the heat generating means with the heat fixing belt sandwiched therebetween; The image is fixed on the recording medium by pressing and heating it, and
In a thermal fixing device that conveys a recording medium toward a paper discharge port by rotation of a thermal fixing belt, the thermal fixing belt is placed between a pressure roller and a paper discharge port in a direction opposite to the conveying direction of the thermal fixing belt. A cooling fan is installed to blow air towards the

[Function] In the heat fixing device of the present invention having the above configuration, when the heat fixing belt rotates, the recording medium is conveyed as the heat fixing belt rotates, and the image formed on the recording medium is heated. It will be established. Then, the recording medium is cooled by a cooling fan provided between the pressure roller and the discharge port, and the recording medium is completely separated from the heat fixing belt. Further, since the blow ratio direction of the cooling fan is set opposite to the conveyance direction of the recording medium, the odor-filled gas is not exhausted directly to the outside from the paper discharge port.

[Example] Hereinafter, an example embodying the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 shows the configuration of a photosensitive and pressure sensitive copying machine 1 to which a heat fixing device of the present invention is applied.

As shown in FIG. 1, this photosensitive and pressure sensitive copying machine 1 uses photosensitive paper consisting of light and pressure sensitive paper 12 (hereinafter referred to as microcapsule paper) and color developer paper 28 (hereinafter referred to as recording paper). .

In addition, the microcapsule paper 12 used in this example
The surface of the support is coated with microcapsules, and the microcapsules contain dye precursors and the like that react with the color developer described below. A color developer is coated on the surface of the support of the color developer paper 28 and develops color by reacting with a dye precursor.
It is described in the specification of No. 9, etc., and is omitted here.

At the top of the copying machine 1, there is a document table glass 2 and a document table cover 3.
A desired original 4 is placed on the original platen glass 2.
The document table cover 3 is closed by lying face down.

A halogen lamp 5a and a reflector 5b are provided below the document table glass 2 in the upper part of the copying machine 1.

A light source unit 5 equipped with a reflecting mirror 8 and the like is disposed so as to be movable back and forth along a shaft 13 extending parallel to the document table glass 2. The light source unit 5 irradiates light in a line toward the document table glass 2 in a direction perpendicular to the movement direction.

The irradiated light passes through the transparent document platen glass 2 and is reflected downward by the document 4 placed thereon.

A mirror part 9 including reflective mirrors 9a and 9b is disposed below the document table glass 2 and is movable separately from the light source section 5, and the light reflected from the document 4 is reflected by the reflective mirrors 8,
The light beams 9a and 9b are reflected in this order and guided in parallel to the moving direction of the light source section 5.

A normally fixed projection lens 7 and a filter 6 for adjusting the color tone of the copied image are disposed below the document table glass 2, and the light reflected by the reflection mirror 9b is directed to the projection lens 7. incident.

The light projected by the lens 7 passes through a group of reflective mirrors 10
a and 10b.

An exposure stage 11 for exposing the microcapsule paper 12 is disposed to the right of the reflective mirror 10b, and a reflective mirror 10c for switching the optical path is disposed between the reflective mirror 10b and the exposure stage 11. ing. Image information on the original document 4 is formed on the microcapsule paper arranged along the exposure table 11.

Further, the reflecting mirrors 10a and 10b are normally fixed, but are set when enlarging or reducing the size of the latent image formed on the microcapsule paper 12, and change the optical path length according to a change in the projection magnification m. Therefore, they are configured to be able to move together in the axial direction of the shaft 13.

On the other hand, a cartridge 15 is disposed in the center of the copying machine 1, and a long microcapsule paper 12 is housed in the cartridge 15, which is removable from the machine while being wound around a cartridge shaft 14.

With the cartridge 15 set at a predetermined position within the machine, the leading end of the microcapsule paper 12 is pulled out toward the exposure table 11. A feed roller 19 is provided below the exposure table 1. A dancer roller 21 for tension adjustment is provided.

To the right of the dancer roller 21 is a large diameter roller 22a.
and a pressure developing device 22 including a backup roller 22b.
is arranged, and on the right side of the pressure developing device 22,
As will be described later, a separation roller 23 is provided to separate the microcapsule paper 12 and color developer paper 28 that are in close contact with each other.
A winding shaft 24 for fitting and holding the microcapsule paper 12 is disposed between the separation roller 23 and the cartridge 15.

Microcapsule paper 1 coming out from the top of cartridge 15
2 is guided by a tension roller 19 and passes above the exposure table 11, and then passes through a dancer roller 21 and a pressure developing device 2.
2 and further guided to a separating roller 23 - after which it is wound onto a winding shaft 24 . Note that the unexposed microcapsule paper 12 after leaving the cartridge 15 is maintained in an unexposed state by the light shielding cover.

A paper feed cassette 29 containing developer paper 28 is installed below the pressure developing device 22 . Above the two paper feed cassettes, a suction cup-type paper feed mechanism 30 that sucks paper using negative pressure suction is arranged, and the developer paper 28 is taken out one by one by the paper feed mechanism 30. . A feed guide 31d, feed rollers 31a, 31b, and 31C are arranged between the paper feeding mechanism 30 and the pressure developing device 22, and the color developing paper 28 is fed by the feed rollers 31a, 31b, 31c, and the feeding speed is 1'.
[3] d and carried into the pressure developing device 22.

A separation chute 27, which will be described later, is disposed on the right side of the pressure developing device 22, a heat fixing device 32 is disposed on the right side of the separation chute 27, and a heat fixing device 32 is disposed on the right side of the heat fixing device 32. A paper discharge tray 33 is provided for storing the color developing paper 28 on which an image has been formed.

Next, the structure of the heat fixing device 32 will be explained in detail with reference to FIG. 2.

As shown in FIG. 2, the copying machine 1 includes a pair of side plates 50 and a plurality of connecting plates 51 installed between the side plates 50. As shown in FIG. The heat roller 52 is rotatably supported by both side plates 50, and a heater 53 made of a halogen lamp or the like is provided inside the heat roller 52. The thermistor 63 is disposed close to the heat roller 52, and under the control of the thermistor 63, the heat roller 52 is heated by the heater 53.
surface temperature or a predetermined temperature. Roller for tensioning 54
is rotatably supported between both side plates 50 around an axis parallel to the heat roller 52, and an endless heat fixing belt 55 is stretched between the heat roller 52 and the stretching roller 54. When the heat roller 52 is rotated counterclockwise by the belt drive motor (path shown), the heat fixing belt 55 is rotated in the same direction to convey the color developer paper 28 as a recording medium on which an image has been formed. will be held.

A pair of rotating plates 56 are rotatably supported by both side plates 50 of the copying machine 1 via support pins 57.
A pressure roller 58 is rotatably supported between them. The pressure spring 59 is provided between the rotary plate 56 and the side plate 50 via support bolts 60, and the biasing force of the pressure spring 59 causes the pressure roller 58 to be attached to the heat roller 52 via the heat fixing belt 55. A predetermined nip pressure is applied to a part of the heat fixing belt 55 by pressing against the lower surface of the outer periphery of the heat fixing belt 55 .

The guide plate 61 is attached between both side plates 50 so as to extend along the conveyance path of the color developer paper 28 by the heat fixing belt 55.
Eject the developer paper 28! A pair of paper discharge rollers 62 for discharging paper onto the no. 33 is provided.

The paper ejection tray 33 is attached to a paper ejection port 35 provided on the right side of the paper ejection roller pair 62.

A cooling fan 63 that rotates counterclockwise in FIG. It is arranged in the opposite direction, that is, facing the heat roller 52. Therefore, the air flow generated by the cooling fan 63 is in the opposite direction to the direction in which the color developing paper 28 is conveyed.

A deodorizing filter 36 and an exhaust fan 37 are provided above the heat fixing belt 55, as shown in FIG. The exhaust fan 37 sucks odor gas generated when the color developer paper 28 is heated and fixed by the heat roller 52 , passes it through the deodorizing filter 36 to turn it into odorless gas, and exhausts it from the exhaust port 35 .

In the above embodiment, the color developer paper 28 constitutes a recording medium, and the heat roller 52 and the tensioning roller 54 constitute a pair of rollers.

Further, the heat roller 52 and the heater 53 constitute a heat generating means.

Furthermore, this copying machine has an autoloading function for automatically setting the microcapsule paper 12 on a predetermined transport path within the apparatus.

This is a function that automatically pulls out the leader film part attached to the tip of the microcapsule paper 12 into the apparatus, transports it inside the apparatus, and winds it around the winding shaft 24. As a result, the microcapsule paper 12 following the rider film section 18 is also wound up on the winding shaft 24, and the setting in the apparatus is completed.

For this automatic loading, a half-moon roller 17 is provided between the roller 19 and the cartridge 15 for pulling out the leader film section, and a take-up shaft 24 is provided between the roller 19 and the cartridge 15.
A separation chute 27 is rotatably mounted to guide the user. Around the winding shaft 24, a makitri guide unit 2 is provided to wind the leader film portion 18.
5 and a machining guide seat 26 are provided.

Next, the operation of this copying machine will be explained.

When the cartridge 15 is set in the copying machine 1, autoloading is started.

The half-moon roller 17 rotates once to several times in the conveyance direction only when autoloading starts, and the leader film section 18
is sent out to roller 20. After that, it stops, and subsequent conveyance is performed by driving the rollers 20.

Makitori guide sea urchin 25. When the automatic loading is completed, the mantle guide shutter 26 and the separation chute 27 are rotated to the position shown by the - dotted chain line, and the leader film section 18 attached to the tip of the microcapsule paper 12 is wound around the winding shaft 24. Makitori guide sea urchin 25. The machining guide seat 261 separation chute 27 returns to the position shown by the solid line and copying is possible.

When the copy start key is operated, the above reflection mirror 8
．． The halogen lamp 5 has a moving speed of 1/m V, where the transport speed of the microcapsule paper 12 is V and the projection magnification is m.
The reflecting mirrors 9a and 9b move at a moving speed of 1/
Moves at 2 mV.

The conveyance speed of the microcapsule paper 12 is determined by the mirror group 8.9a.
, 9b is synchronized as described above,
Latent images of predetermined lines of the document 40 are sequentially formed on the microcapsule paper 12 as it passes through the exposure stage 11 . Note that the above-mentioned predetermined speed ratio is predetermined based on the set value of the magnification.

The microcapsule paper 12 on which the latent image has been formed is transported,
The topmost color developing paper 28 of the paper feed cassette 29 is fed to the paper feed mechanism 30.
．． It is conveyed by feed rollers 31a, 31b, 31C, etc.

The pressure developing device 22 is supplied with the microcapsule paper 12 and the color developer paper 28 in close contact with each other, and the microcapsule surface on which the latent image of the microcapsule paper 12 is formed and the color developer of the color developer paper 28. The application surface is integrally sandwiched between the large diameter roller 22a and the backup roller 22b in a state in which they are in contact with each other on the inside, and pressure is applied. This pressure destroys the unexposed microcapsules and forms an image on the developer paper 28.

The microcapsule paper 12 and the color developer paper 28 that have come out of the pressure development device 22 are separated by a separation roller 23, and then the color development of the color developer paper 28 is promoted by the heat roller 52 of the heat fixing device 32 to form an image. After that, the paper is delivered to the paper ejection tray 33 by the paper ejection roller pair 62. Note that the separated microcapsule paper 12 passes through a separation roller 23 and is transferred to a winding shaft 2.
4.

Next, the operation of the heat fixing device 32 will be explained in detail.

When the developer paper 28 with an image formed on its surface is inserted into the heat fixing device 32, the heat roller 5 is moved by a motor (not shown).
2, the heat fixing belt 55 is rotated counterclockwise in FIG. 2, and the heater 53 in the heat roller 52 is energized.

As a result, while the color developer paper 28 is pressed against the heat fixing belt 55, it is heated by the heat of the heater 53 via the heat roller 52 and the heat fixing belt 55, and the color developer on the color developer paper 28 is melted. Therefore, the developer paper 28 is stuck to the lower running portion of the heat fixing belt 55 and is fixed without being conveyed as the heat fixing belt 550 rotates. Then, the developer paper 28 is cooled by the air flow blown out by the cooling fan 63, and the developer on the developer paper 28 solidifies.
The color developing paper 28 is peeled off from the heat fixing belt 55 by the curvature of the stretching roller 54, and is discharged onto the paper discharge tray 33 by a pair of paper discharge rollers 62.

In addition, since the air outlet 63a of the cooling fan 63 is arranged facing the heat roller 52, odor gas generated during the process of heating and fixing the color developer paper 28 is exhausted from the paper discharge port 35 of the color developer paper 28. The air is sucked in by an exhaust fan 37 disposed above the heat fixing device 32 and passed through a deodorizing filter 36. As a result, the odorous gas is changed to an odorless gas, which is exhausted to the outside of the copying machine 1 through the exhaust port 34.

As described in detail above, in the copying machine 1 of this embodiment, the cooling fan 63 is disposed so that the air blowing direction is opposite to the direction in which the color developer paper 28 is conveyed.
can be completely separated from the heat fixing belt 55, and the odor gas generated when heating the color developing paper 28 is directly discharged from the paper discharge port 3.
No exhaust from 5. Since an exhaust fan 37 is disposed above the heat fixing belt 55 via a deodorizing filter 36, the odorous gas can be changed into odorless gas and exhausted from the exhaust port 34 to the outside of all copies.

[Effects of the Invention] As is clear from the detailed description above, the heat fixing device of the present invention is such that even if the heat fixing device is a heat fixing device that heats while being conveyed by the rotation of the heat fixing belt, the air blowing direction can be adjusted to the direction of the recording material. A cooling fan installed in the opposite direction to the conveyance direction of the medium allows the recording medium to be completely separated from the heat fixing belt, and also directly discharges the odor gas generated when the recording medium is heated. It has the excellent effect of not causing exhaust from the mouth.

[Brief explanation of drawings]

1 and 2 show an embodiment embodying the present invention, FIG. 1 is a sectional view showing the configuration of a copying machine to which the heat fixing device of the present invention is applied, and FIG. FIG. 3 is an enlarged cross-sectional view. In the figure, 28 is developer paper, 32 is a heat fixing device, 35 is a paper discharge port, 52 is a heat roller, 53 is a heater, 54 is a tension roller, 55 is a heat fixing belt, 58 is a pressure roller, and 63 is a It is a cooling fan.

Claims (1)

[Claims] 1. A pair of rollers arranged a predetermined distance apart, a heat fixing belt stretched between the pair of rollers, a heat generating means arranged between the pair of rollers, and the heat fixing belt and a pressure roller that presses against the heating means with the image formed thereon, and the recording medium on which the image is formed is sandwiched between the heat fixing belt and the pressure roller and pressurized and heated to fix the image on the recording medium. In a thermal fixing device that conveys a recording medium toward a paper discharge port by rotation of a heat fixing belt, a roller is provided between the pressure roller and the paper discharge port in a direction opposite to the conveying direction of the heat fixing belt. A heat fixing device comprising a cooling fan that blows air toward the heat fixing belt.