JPH0764426A - Fixing device of image output device - Google Patents

Abstract

PURPOSE:To use the heat of a quartz lamp effectively to heat a heat roller and to enable the width of a heat-roller type fixing device to be reduced by preventing heat from leaking from the end of the heat roller. CONSTITUTION:A quartz lamp 10 is disposed inside a heat roller that constitutes a fixing device, and infrared rays output from its filament are applied to the inner surface of the heat roller to give heating action. A metallic sleeve member 20 which is treated to be able to reflect infrared radiation is installed outside the paper fixing area H of the heat roller 1 and around a portion that holds lamp foil 13 located at the end 11 of the quartz lamp 10, and any light leaking from an opening at the end of the heat roller is reflected by the sleeve member so as to enable effective use of heat.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a quartz lamp arranged inside a heat roll of a fixing device, and more particularly to a red lamp at the end of the heat roll so that heat can be prevented from leaking from the end of the heat roll. The present invention relates to a fixing device for an image output device, which is provided with a means for reflecting external light and is capable of reflecting the light from the end portion of the lamp toward the inside of the heat roll.

[0002]

2. Description of the Related Art Like electrophotographic copying machines and printers,
In an image output apparatus that makes a copy using an electrophotographic system, a toner image created on an image bearing member such as a photoconductor drum is transferred to a sheet, and the sheet carrying the toner image is fixed through a fixing device to make a copy. The method of creating is used. As the fixing device, a device of a heat roll system is often used, and in the fixing device of the heat roll system, a heat roll having a built-in heat source inside, and a predetermined pressure with respect to the heat roll. And a pressure roll to be pressed. Then, by passing the paper in a state in which the surface of the paper on which the toner image is transferred corresponds to the heat roll, the toner is melted by the heat of the heat roll and pressed against the paper to make a copy.

In the heat roll type fixing device as described above, for example, as shown in FIG. 5, the quartz lamp 10 is housed inside a pipe-shaped heat roll 1 made of iron, aluminum or the like. A filament 12 as a heating element is arranged inside the quartz lamp 10.
Also, the lamp ends 11 are provided on both ends of the filament 12.
The lamp foil 13 provided in the lamp foil 13 is connected to the outside of the lamp foil 13, and the input terminal 15 contacts the outside to supply electric power. The lamp 10 is held at a fixed position. Further, the end portion of the heat roll 1 is rotatably supported by a frame of a copying machine or the like via a bearing 2, and is rotated at a constant speed by a drive mechanism (not shown). Then, in the fixing device using the heat roll, when the main switch of the image output device is turned on, the heat roll is rotated while energizing the quartz lamp, and the surface of the roll is kept at a constant temperature (for example, 1
90 ° C.), the image output device is set to an operable state, and even if the paper passes and the surface temperature of the roll decreases, the energization is performed to keep the surface temperature of the roll constant. Control is performed so that the fixing temperature can be maintained within an allowable range.

Heat roll 1 as shown in FIG.
In, in the position close to the outer portion of the paper fixing area, the support portion by the bearing is formed, so that the heat of the end portion of the quartz lamp heats the end portion of the heat roll,
There is a problem that the end portion of the roll is excessively heated, and the portion of the lamp foil arranged at the end portion of the lamp is affected by heat and the durability is reduced. Therefore, in the conventional heat roll, for example, in the example shown in FIG. 5, when the lamp end portion is arranged so as to project to the position shown by the phantom line, the heat inside the heat roll is shown in the reflected light R. Even if the heat is transmitted to the end of the heat roll, the lamp foil is not excessively heated, and the life of the quartz lamp is not significantly affected.

[0005]

However, as shown by the phantom line in FIG. 5, if the end of the lamp is largely projected toward the outside of the heat roll, the heat roll of the image output device is supported. On the side of the frame,
It is necessary to set a large margin for the quartz lamp. Therefore, in a comparatively small electrophotographic copying machine or the like, the width of the device is unnecessarily increased, which hinders the downsizing and causes an increase in the cost of the device. Further, in the conventional fixing device as described above, since the heat released from the end of the heat roll to the outside is relatively large, the temperature drop at both ends of the paper fixing area of the heat roll becomes a problem. There is.

Therefore, in order to solve the above-mentioned heat dissipation problem, for example, as disclosed in Japanese Patent Laid-Open No. 1-319774, a quartz lamp is projected further outward from the end of the heat roll, It has been proposed to arrange it inside a small-diameter pipe-shaped member. However, in the above-mentioned conventional example, there is a problem that the quartz lamp is largely projected to the side portion of the heat roll and the width of the apparatus is increased. Further, in JP-A-64-7792, a heat-resistant paint is applied to the end of the quartz lamp to prevent the temperature of the end of the quartz lamp from decreasing. When the means is used, there is a concern that the durability of the lamp is greatly affected by the temperature rise of the lamp foil portion. Furthermore, in the example disclosed in Japanese Patent Laid-Open No. 2-163784,
It is shown that a heat-shielding protruding member is arranged at the end of the heat roll to prevent heat inside the heat roll from escaping from the end. However, disposing the heat shield plate at the end of the heat roll not only complicates the structure of the roll itself, but also attaches the heat shield plate to the roll member to which a relatively large pressing force is applied. Providing a hole or the like also greatly affects the strength thereof and is not very preferable.

[0007]

SUMMARY OF THE INVENTION The present invention solves the problems of the conventional fixing device as described above. Even if the end of the quartz lamp is configured so as not to protrude to the outside of the heat roll, the end of the lamp will not pass. An object of the present invention is to provide a device that does not heat and does not allow heat to escape from the end of the heat roll.

[0008]

SUMMARY OF THE INVENTION According to the present invention, a heat roll and a pressure roll are provided with a predetermined nip pressure, and both rolls are arranged to face each other, and a toner image is formed between the both rolls. The present invention relates to a fixing device that performs a fixing action by passing a sheet to be carried. In the present invention, a quartz lamp is arranged inside the heat roll, the end of the quartz lamp is covered with a reflecting member that reflects light, and the light output from the quartz lamp is transferred from the end of the heat roll to the outside. It constitutes a means of preventing release. Further, in the present invention, the reflecting member arranged at the lamp end portion is configured by a sleeve member having heat resistance such as metal, and the sleeve member is configured to match the outer shape of the lamp end portion, or A means for preventing the heat inside the heat roll from being released to the outside by aligning the small diameter portion of the sleeve member with the end of the lamp and integrally providing a flange member having a diameter smaller than the inner diameter of the heat roll. You can Further, in the present invention, it is possible to form the reflecting member arranged at the end portion of the lamp by white or silver coating or plating.

[0009]

As described above, in the fixing device of the image output apparatus of the present invention, since only the member that reflects heat is arranged at the end of the lamp, the heat roll structure does not become complicated. It is possible to prevent the lamp foil arranged at the end portion of the lamp from being subjected to an excessive heating action and to prevent the life of the heating lamp from being affected. Further, in the present invention, the quartz lamp arranged inside the heat roll is provided with means for reflecting the heat toward the inside at the end of the lamp, so that the heat is dissipated from the end of the heat roll to the outside. The temperature distribution in the sheet fixing area of the heat roll can be maintained in a good state.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A fixing device for an image output device of the present invention will be described with reference to the illustrated example. The example shown in FIG. 1 shows a structure of an end portion of a heat roll in a fixing device of a heat roll type, and like the case of a conventional heat roll,
A quartz lamp 10 is arranged inside the heat roll 1 to configure a mechanism for heating the heat roll 1. The end portion of the heat roll 1 is configured to be rotatable via a bearing 2 arranged between the heat roll 1 and the frame of the image output device, and the sheet is nipped between the heat roll 1 and a pressure roll (not shown). , To fix the paper. A quartz lamp 10 arranged inside the heat roll 1 is a lamp in which a filament 12 is provided inside a glass tube and an end portion of the filament 12 is provided at a lamp end portion 11 similarly to a conventionally used quartz lamp. It is connected to the foil 13. Then, the input terminal 15 is connected to the portion exposed to the outside of the lamp foil 13 to supply power, and a temperature sensor (not shown) arranged at a predetermined position on the surface of the heat roll is used for the quartz lamp. The energization is controlled so that the surface temperature of the heat roll can be set within a certain range.

In the quartz lamp 10, a sleeve member 20 as shown in FIG. 2 is arranged at the lamp end portion 11, and the infrared light outputted from the end portion of the filament 12 of the quartz lamp by the sleeve member 20. It constitutes a mechanism that reflects light back toward the inside. The sleeve member 20 is made of a white or silver-colored metal or a heat-resistant non-metal member (for example, ceramics) in a cylindrical shape so as to reflect infrared light. Although the widened portion 22 is provided and the slit 23 is provided in the lengthwise direction, the slit can be formed to have an arbitrary width so that a large gap is not formed when the slit 23 is attached to the end portion of the lamp. Form.
Then, with the sleeve member 20 slightly expanded,
By mounting the sleeve member 20 on the lamp end portion 11, the sleeve member 20 provided on the lamp end portion 11 reflects infrared light output from the vicinity of the lamp foil 13 toward the inside of the quartz lamp 10. Further, infrared light output from the quarz lamp 10 toward the inner surface of the heat roll 1 is also indicated by an arrow R.
Is reflected in the direction of, and a part of the light is transmitted to the surface of the sleeve member 20.
Since it is reflected on the surface of the quartz lamp lamp lamp 1
No extra heating of 3. Therefore, by arranging the sleeve member as shown in FIG. 1, the outside of the sheet fixing area H of the heat roll 1 can be
It is possible to prevent the fixing temperature from dropping extremely, and to make the surface temperature distribution of the heat roll uniform.

Apart from the embodiment shown in FIGS.
In the present invention, as shown in FIGS. 3 and 4, the sleeve member 25 provided with the collar member 27 can be attached to the end portion of the lamp. Similar to the sleeve member shown in FIG. 2, the sleeve member 25 shown in FIG. 4 is made of a material such as metal capable of exhibiting a function of reflecting heat, and has a small diameter corresponding to the diameter of the lamp end 11. The portion 26 and the end portion of the small diameter portion 26 are combined with a large diameter collar member 27 to be integrally formed, and a slit 28 is provided in the length direction of the sleeve member. Further, the collar member 27 provided on the sleeve member 25 is configured to have a diameter slightly smaller than the inner diameter of the heat roll so that the light reflected toward the outside of the sleeve member can be reflected. The sleeve member shown in each of FIGS. 2 and 4 is attached to the end of the lamp in a state where the small-diameter portion is expanded, and the outer peripheral portion of the lamp end is lightly tightened by the elasticity of the sleeve member. Can be made. Therefore, the sleeve member of the present invention is
Even if the temperature of the quartz lamp rises, it can be kept attached to the end of the quartz lamp in a good condition and exhibits the function of preventing heat from leaking from the end of the lamp to the outside of the heat roll. It becomes possible to do.

The sleeve member 25 of the present invention constructed as described above is arranged inside the heat roll 1 as shown in FIG.
For the lamp foil 13 arranged at both ends of the
5 is connected to supply power. In the quartz lamp 10, the flange member 27 of the sleeve member 25 is provided so as to be located outside the sheet fixing area H of the heat roll, and the reflected light R of infrared light output from the quartz lamp inside the heat roll 1 is The inner surface of the heat roll is irradiated with the heat and acts to heat from the inside. Further, the reflected light R of infrared light that is emitted to the outside of the roll at the end of the quartz lamp 10 is reflected on the inner surface of the sleeve member 25 and does not leak to the outside. Further, as shown in FIG. 3, the light R reflected on the inner surface of the heat roll
Is in a state of being reflected toward the inner surface of the heat roll by the brim member 27, the heat inside the heat roll 1 is prevented from being released from the end portion to the outside, and the heat output from the filament is effectively Can be used.

As described above, when the means for reflecting light is provided at both ends of the quartz lamp, instead of mounting the sleeve member on the end of the lamp as shown in each of the embodiments, The surface of the quartz glass tube may be plated with metal. As the metal plating, any metal material can be used as long as it can form a silver or white anti-slope, and the thickness of the plating layer and the like can also be formed arbitrarily. Further, in the quartz lamp of the present invention, it is also possible to form a layer that reflects light by using a heat-resistant coating material on the end portion of the lamp, and the coating material has a surface temperature of the lamp of about 400. Since the temperature will be in ° C, good results can be obtained by selecting a paint that can withstand the high heat.

[0015]

In the fixing device of the image output apparatus of the present invention, the heat reflecting means as described above is arranged at the end of the lamp. Therefore, the sleeve member is arranged so as to cover the end of the lamp. Or by performing a surface treatment such as plating, it is possible to prevent the heat of the quartz lamp from being radiated outward from the end of the heat roll. Further, the downsizing of the fixing device makes it possible to reduce the size of the image output device, which also has a good effect on the manufacturing cost of the device. Therefore, since it is not necessary to project the end of the quartz lamp to the outside of the heat roll, it is not necessary to make the width of the fixing device excessively wide, and the device can be made compact. Also,
In the heat roll of the present invention, the heat output from the quartz lamp can be used effectively, so that the state of temperature distribution in the paper fixing area can be set satisfactorily, and the temperature drop at the side of the paper fixing area, etc. Can be prevented.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a configuration of an end portion of a heat roll of the present invention.

FIG. 2 is a perspective view of a sleeve member of the present invention.

FIG. 3 is an explanatory diagram of a second embodiment of the heat roll of the present invention.

FIG. 4 is a perspective view of a sleeve member used in FIG.

FIG. 5 is an explanatory diagram showing a configuration of a conventional heat roll.

[Explanation of symbols]

1 Heat Roll, 10 Quartz Lamp, 11
Lamp end, 12 filaments, 13
Lamp foil, 20/25 sleeve member, 22 expanded portion, 27 collar member.

Claims (4)

[Claims] 1. A heat roller and a pressure roller are arranged so as to face each other in a state where a predetermined nip pressure is applied, and a paper carrying a toner image is passed between the rollers to fix the toner image. In the fixing device that operates, a quartz lamp is arranged inside the heat roll, the end of the quartz lamp is covered with a member that reflects light, and the light output from the quartz lamp is output from the end of the heat roll to the outside. A fixing device for an image output device, characterized in that it comprises means for preventing the discharge of the toner. 2. A reflecting member arranged at the end of the lamp,
The fixing device for an image output apparatus according to claim 1, wherein the fixing device is formed of a heat-resistant sleeve member such as metal, and the sleeve member is formed to match the outer shape of the lamp end portion. 3. A reflecting member arranged at the end of the lamp,
It is composed of a heat-resistant sleeve member such as metal, the small diameter portion of the sleeve member is aligned with the end of the lamp, a collar member having a diameter smaller than the inner diameter of the heat roll is integrally provided, and heat inside the heat roll is secured. The fixing device for an image output apparatus according to claim 1, further comprising means for preventing discharge to the outside. 4. A reflecting member arranged at the end of the lamp,
The fixing device for an image output device according to claim 1, wherein the fixing device is formed by white or silver plating or painting.