JPH03202518A - Heat fixing device - Google Patents

Abstract

PURPOSE:To promote development of a sensitized sheet and to increase the heat fixing speed by a method wherein an air generating source, a temperature control device, and a cross blower device are mounted in a casing having a heat reflecting function, and developing sheets are made to pass therethrough. CONSTITUTION:A hot blast transmission mechanism is formed in a casing 44 with a heater 40, a temperature sensor 41, a cross flow fan 42, and a motor 43, and after enough polishing of an inner surface 44a of the casing 44, nickel chrome plating is applied. The heater 40 insulated by mica 45 is mounted to the two ends of the internal part of the casing 44, a temperature sensor 41 is mounted to the heater 40, and temperature is controlled to a specified value. The cross fan 42 is run with the aid of the motor 43, and air is fed to the heater 40 to feed downward hot blast. This constitution enables promotion of coloring of a developing sheet passing in the direction of an arrow mark.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a heat fixing device for an image forming apparatus that forms an image on a photosensitive recording medium.

[Prior Art] In conventional image forming apparatuses, for example, those that form a latent image on microcapsule paper or the like and then integrate it with a photosensitive recording medium such as developer paper for pressure development, the developer paper is transferred to the developer paper using a heat fixing device. The image is formed by heating and thermal fixing.

The heat fixing device has a configuration in which a heater and a heat transfer mechanism that sprays heat from the heater toward the photosensitive surface of the photosensitive recording medium are covered by a casing.

[Problems to be Solved by the Invention] However, the casing is often made of iron, and the heat emitted from the heater is absorbed by the casing, causing a problem of loss of heat that should be used for thermal fixing.

The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to provide a heat fixing device in which the heat emitted from the heater is not absorbed by the casing and can be effectively used for heat fixing. It is said that

[Means for Solving the Problems] In order to achieve this object, the heat fixing device of the present invention covers a heater and a hot air transmission mechanism that blows heat from the heater toward the surface of a photosensitive recording medium with a casing. , a heat reflector is provided on the inner wall surface of the casing.

[Function] In the heat fixing device of the present invention having the above-described configuration, heat from the heater is blown toward the surface of the photosensitive recording medium by the hot air transmission mechanism, and thermal fixation is performed.

At this time, the heat from the heater is reflected by the heat reflector on the inner wall surface of the casing.

[Embodiments] Hereinafter, embodiments embodying the present invention will be described with reference to the drawings.

In the photosensitive and pressure sensitive copying machine 1 of this embodiment, as shown in FIG. 2, photosensitive paper consisting of microcapsule paper 12 and color developer paper 28 is used.

The surface of the support of the microcapsule paper 12 used in this example is coated with microcapsules, and the microcapsules contain a dye precursor that reacts with a color developer, which will be described later. . 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, but the details are described in US Pat. No. 4,399,209 and the like and will not be described 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.
is placed face down and the document table cover 3 is closed.

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 section 5 irradiates light onto the document table glass 2 in a line 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 section 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.
The light is reflected in the order of b and guided 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 10a,
10b.

Microcapsule paper 12 is placed on the right side of the reflective mirror 10b.
An exposure table 11 for exposing the light is provided, and a reflecting mirror 1
A reflecting mirror 10c for switching the optical path is disposed between 0b and the exposure table 11.

Microcapsule paper 12 arranged along exposure table 11
The image information on the document 4 is formed into an image.

In addition, 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 the elongated 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 and a dancer roller 21 for tension adjustment are provided below the exposure table 11.

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. The microcapsule paper 12 that comes out from the top of the cartridge 15 is guided by a tension roller 19 and passes above the exposure table 11, and then a dancer roller 21,
After passing through the pressure developing device 22 and further guided to the separation roller 23, it is wound up on the winding shaft 24. Note that the unexposed microcapsule paper 1 after leaving the cartridge 15
2 is maintained in an unexposed state by a light-shielding cover. A paper feed cassette 29 containing developer paper 28 is installed below the pressure developing device 22 . Above the paper feed cassette 29, a suction cup-type paper feed mechanism 30 that sucks paper using negative pressure suction is arranged, and the developing paper 28 is taken out one by one by the paper feed mechanism 30.

A feed guide 31d1 and feed rerollers 31a, 31b, and 31C are disposed between the paper feeding mechanism 30 and the pressure developing device 22, and the color developing paper 28 is moved between the feed rollers 31a, 31.
b, 31c, and are conveyed by a feed guide 31d and carried into the pressure developing device 22.

A heat fixing device 32, which will be described later, is disposed to the right of the pressure developing device 22, and a paper discharge tray 33 for storing the developer paper 28 on which an image has been formed is disposed to the right of the heat fixing device 32. ing.

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 leader film section 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 attached to guide the user. An upper machining guide 25 and a lower machining guide 26 are disposed around the winding shaft 24 for winding the leader film.

FIG. 1 is a detailed structural diagram of a casing 44 in a heat fixing device 32 installed in the photosensitive pressure-sensitive copying machine 1 shown in FIG. 2 and its interior. Inside the casing 44, the heater 40 is attached to a mica plate (insulator) 45, and the mica plate 45 is fixed to the casing 44 at both ends. A temperature sensor 41 is installed in the heater 40.
The temperature at zero is controlled to be constant. And motor 43
The cross flow fan 42 rotates, and the heater 40
By blowing the hot air downward, the developing paper 28 passing in the direction shown by the arrow is accelerated in color development and thermally fixed.

The inner wall surface 44a of the casing 44 is sufficiently polished and is plated with nickel chrome so that the heat from the heater 40 is reflected.

Next, the action 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 at the start of autoloading, and feeds the leader film portion to the roller 20. Thereafter, it stops, and subsequent conveyance is performed by driving the rollers 20.

The upper machining guide 25, the lower machining guide 26, and the separation chute 27 are rotated to the positions shown by the - dotted chain line, and the leader film attached to the tip of the microcapsule paper 12 is automatically wound around the winding shaft 24. When loading is completed, the upper machining guide 25, the lower machining guide 26, and the separation chute 27 return to the positions indicated by solid lines and copying is possible.

When the copy start key is operated, the reflecting mirror 8 and halogen lamp 5a move at a moving speed of 1/mV, where the conveying speed of the microcapsule paper 12 is V1 projection magnification m, and the reflecting mirrors 9a and 9b move at a moving speed of 1/mV. 1/2 m
Move with V.

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 4 are sequentially formed on the microcapsule paper 12 as it passes through the exposure stage 11 . Note that the predetermined speed ratio is predetermined based on the setting 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 coated surface is integrally sandwiched between the dog scratching 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 microcapsule paper, and the developer paper 28
An image is formed on top.

The microcapsule paper 12 and the color developer paper 28 that have come out of the pressure developing device 22 are separated by a separation roller 23, and the color developer paper 28 is accelerated in color development by a heat fixing device 32 to form an image, and is then discharged. The paper output tray 33 is moved by the paper roller 32b.
It will be transported to In addition, the separated microcapsule paper 12
is wound up on a winding shaft 24 via a separation roller 23.

As is clear from the detailed description above, in the heat fixing device 32 of this embodiment, the heat from the heater 40 is blown toward the developing paper 28 by the cross flow fan 42 and thermally fixed. Since the heat is reflected by the heat reflector on the inner wall surface 44a of the casing 44,
The heat emitted from the heater 40 is not absorbed by the casing 44 and can be effectively used for thermal fixing.

Note that any coating method for the heat reflector can be applied as long as a metal with high heat reflectivity is used, such as aluminum vapor deposition.

Other changes may be made without departing from the spirit of the invention.

[Effects of the Invention] As is clear from the above detailed description, in the heat fixing device of the present invention, heat from the heater is blown toward the surface of the photosensitive recording medium by the hot air transmission mechanism and thermally fixed. Since the heat from the heater is reflected by the heat reflector on the inner wall surface of the casing, the heat emitted from the heater is not absorbed by the casing and can be effectively used for heat fixing. Therefore, the photosensitive recording medium can be thermally fixed quickly, improving image quality such as glossiness and speeding up the fixing process.

[Brief explanation of drawings]

1 and 2 show an embodiment embodying the present invention. FIG. 1 is a diagram of the casing of the heat fixing device of this embodiment and its internal structure, and FIG. 1 is an overall configuration diagram of a photosensitive and pressure-sensitive copying machine to which a heat fixing device is applied. In the figure, 28 is developer paper, 32 is a heat fixing device, 40 is a heater, 42 is a cross flow fan, 44 is a casing, 44
a is the inner wall surface.

Claims (1)

[Claims] 1. A heat fixing device disposed opposite to the surface of a photosensitive recording medium on which an image is formed, comprising: a heater; and hot air that blows heat from the heater toward the surface of the photosensitive recording medium. A heat fixing device characterized in that a transmission mechanism is covered with a casing, and a heat reflector is provided on an inner wall surface of the casing.