JPS63281181A - Fixing device - Google Patents

Abstract

PURPOSE:To contrive to improve the thermal efficiency of non-contact heating by placing a reflecting means for reflecting a far infrared radiation radiated from a far infrared radiation substance toward the surface of a recording material, in the periphery of a halogen lamp heater provided with a metallic cylinder having the far infrared radiation substance on the surface of a glass tube. CONSTITUTION:A halogen lamp heater 1 has an electrode 7 on both ends of a sealed quartz glass tube 5, and in its inside, a tungsten filament 6 for connecting both the electrodes is provided. Also, on the surface of the quartz glass tube 5, alumite plating is performed to a metal whose thermal conductivity is high, for instance, aluminum 9 so that the thermal absorptivity is raised and the surface temperature becomes uniform in the axial direction, and a far infrared radiation substance layer 8 is provided thereon. Moreover, in the periphery of the halogen lamp heater 1, a reflecting plate 2 for reflecting the far infrared radiation radiated from the far infrared radiation substance 8 toward the surface of a recording material 3 is placed. In such a way, the thermal efficiency can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention is utilized in the field of fixing technology for electrophotographic devices, and particularly relates to a fixing device that thermally fixes a recording material having an unfixed toner image by non-contact heating. Regarding.

(Prior Art and Problems) In the fixing of electrophotographic devices, a thermal fixing device that non-contactly heats a recording material with an unfixed toner image is widely known. There are fixing devices, flash fixing devices, etc., but all of them have problems.

First, there is a chamber fixing device, which has a sheathed heater that heats the toner to red heat, heats the recording material with the heat, and fixes the toner by heating it and melting the toner. but,
Not only did the sheathed heater body not have good thermal efficiency, but much of its radiated heat was radiated to areas other than the recording material, resulting in a lot of energy loss.

In addition, thermal roller fixing devices that press the recording material against a roller with a built-in heating source have the problem of heat escaping through the roller. The problem is very similar to that of the chamber fixing device described above. Furthermore, flash fixing devices require large capacitors to instantaneously apply high voltage to the flash lamp to cause it to emit light.
This increases the size of the device and makes it difficult to increase the speed due to the charging time of the capacitor.

(Means for Solving the Problems) An object of the present invention is to provide a fixing device that can solve the above-mentioned problems and improve its thermal efficiency in non-contact heating.

The present invention aims to achieve the above objects.

In an apparatus for thermally fixing a recording material having an unfixed toner image by non-contact heating, the heat source for non-contact heating consists of a halogen lamp heater equipped with a metal cylinder containing a far-infrared emitting substance on the surface of a glass tube. It is constructed by disposing a reflecting means around the halogen lamp heater for reflecting far infrared rays emitted from the far infrared ray emitting substance toward the surface of the recording material L.

(Embodiment) Hereinafter, a device according to an embodiment of the present invention will be described based on the accompanying drawings.

Figure 1 is a sectional view of the device of this embodiment taken in a plane perpendicular to the longitudinal axis of the halogen lamp heater as a heat source;
This figure is a sectional view of the halogen lamp heater of FIG. 1 taken along a plane including the axis.

In FIG. 1, reference numeral 1 denotes a halogen lamp heater, and above the halogen lamp heater, a reflecting plate 2 is disposed to cover the halogen lamp heater.

As shown in FIG. 2, the halogen lamp heater 2 has electrodes 7 at both ends of a sealed quartz glass tube 5, and a tungsten filament 6 connecting the two electrodes is arranged inside.

The surface of the quartz glass tube 5 is covered with a metal 1 having high thermal conductivity.
For example, the aluminum 9 is plated with alumite to increase the heat absorption rate and to make the surface temperature uniform in the axial direction, and furthermore, a far-infrared emitting material layer 8 is provided thereon. As the far-infrared emitting material, for example, a material consisting of 75% betalite, 8.4% lithium carbonate, 7.0% limestone, 2.8% zinc white, and 6.8% aluminum hydroxide is used.

Here, the above tungsten filament will be explained in comparison with a case where a conventional nichrome wire heater is used. When a nichrome wire is used instead of the tungsten filament shown in Figure 2, the heat capacity of the halogen lamp heater is 8 J/, while the heat capacity of the nichrome wire heater is 19 J/.
J/, and since nichrome wire heaters need to self-heat up to 600-700°C in order to radiate heat, most of the energy used to reach that temperature after power is supplied is spent on self-heating. It ends up. Therefore, it takes a relatively long time for the aluminum 9 to reach the set temperature of the far-infrared emitting material layer (for example, about 250 to 350° C. in the present invention). On the other hand, in the case of a halogen lamp heater, since the heat capacity is small and the heater itself has good startup characteristics, it takes only a short time for the aluminum 9 to reach the set temperature of the far-infrared radiator JR layer.

Next, the far-infrared material 8 provided on the upper aluminum 9 of the halogen lamp heater used in the present invention has a characteristic of selectively emitting far-infrared rays having a wavelength of 5 μι or more. Since the peak value of the radiant energy of a halogen lamp heater exists near a wavelength of 1.24 m, the far-infrared material mentioned above will pass through wavelengths in this vicinity. Therefore, aluminum 9 with good thermal conductivity is used. By placing it around a halogen lamp heater, it absorbs near-infrared rays and raises the temperature. Also, by controlling the surface temperature of the far-infrared emitting material layer 8 on the surface of the aluminum 9 within a range of 250°C to 350°C.

As shown in FIG. 3, far infrared rays can be efficiently radiated. Further, the emitted far infrared rays are reflected by a reflecting plate 1 (see FIG. 1) made of aluminum or copper, and radiated to recording paper 3, which is an object to be heated. The reflecting plate 2 is preferably made of a material with high reflectivity such as copper or aluminum, and its shape is preferably radial so that the reflected far infrared rays reach the recording paper 3 at right angles.

Furthermore, adding the effect of Aluminum 9, the present invention is basically radiation fixing using far infrared rays, or in fact, heat conduction or near infrared rays radiated from a halogen lamp are used to connect the fixing device and the nearby air. It is heated and enhances the fixing effect. In order to effectively utilize this effect, aluminum 9
This improves the heat capacity of the system, and by applying alumite plating and increasing the specific heat, the effect is further enhanced.

In addition, in order to deal with the problem of peeling, rather than directly coating far-infrared emitting ceramics on quartz glass,
It is more advantageous to apply coach ink to the aluminum surface.

(Effects of the Invention) In the non-contact heating method as described above, the present invention uses a halogen lamp heater having a metal cylinder around it as a heat source and a layer of far-infrared radiation emitting material on the surface of the halogen lamp heater to increase thermal efficiency. We decided to reflect the emitted far infrared rays onto the recording material containing the unfixed toner image using a reflector.
Thermal efficiency can be further improved, and its power is particularly demonstrated in low-speed machines such as copying machines, and the weight reduction becomes "Tffi", resulting in effects such as cost reduction.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of an apparatus according to an embodiment of the present invention, and FIG.
A cross-sectional view of the halogen lamp heater used in the stirrup shown in FIG.・・・・・・・・・・・・Halogen lamp heater 2・
......Reflection means (reflection plate) 3...
...... Recording material 4 ...... Unfixed toner image 8 ---
−−・・・・・・Far-infrared emitting material 9・・・・・・・・・
...Metal cylinder (aluminum) patent applicant
Canon Co., Ltd. Representative Patent Attorney Fuji
Oka Microton 1 Figure 3 Figure 0.10.20.512 5102050100 waves
Length (μm)

Claims (2)

[Claims] (1) In a device that thermally fixes a recording material with an unfixed toner image by non-contact heating, the heat source for non-contact heating is a halogen lamp heater equipped with a metal cylinder containing a far-infrared emitting substance on the surface of a glass tube. A fixing device comprising: a reflecting means arranged around the halogen lamp heater to reflect far-infrared rays emitted from the far-infrared emitting substance toward the surface of the recording material. (2) The fixing device according to claim (1), wherein the halogen lamp heater is connected to a control means for controlling the surface temperature of the metal tube to a predetermined temperature.