KR20060136060A - Heating roller and image fixing apparatus using the same - Google Patents

Abstract

The disclosed heating roller includes an outer aluminum pipe having a Teflon layer formed on an outer surface thereof; A primer layer provided inside the outer aluminum pipe; An outer insulating layer provided inside the primer layer; A heating coil provided inside the outer insulating layer; An internal insulation layer provided inside the heating coil; And an inner aluminum pipe provided inside the inner insulating layer and having a predetermined expansion force. The above-mentioned heating roller is used as an image fixing unit which is installed in close contact with the pressure roller at a predetermined pressure and fixes the developed image on the recording medium.

Description

Heat roller and image fixing device using same {{HEATING ROLLER AND IMAGE FIXING APPARATUS USING THE SAME}

1 is a partial cross-sectional view showing the configuration of a conventional heating roller for an image fixing apparatus;

2 is a view showing an example of an image forming apparatus applied to the present invention;

3 is a view showing the configuration of a heating roller according to an embodiment of the present invention, and

4 is an enlarged view illustrating the IV display unit of FIG. 3.

<Description of Main Parts of Drawings>

200: fixing device 210: heating roller

211: outer pipe 212: primer layer

213: heating coil 214: internal insulation layer

215: outer insulation layer 216: inner pipe

217: Teflon layer 230: pressure roller

The present invention relates to a heating roller and an image fixing apparatus using the same, and more particularly, to a heating roller and an image fixing apparatus using the same to solve the slip problem of the internal structure when the roller rotates.

Background Art [0002] Usually, an apparatus using an electrophotographic method such as a copying machine, a facsimile, a laser beam printer, or the like is provided with a fixing unit for fixing a toner image formed on a sheet in an image forming unit on a recording medium by high temperature and high pressure. The fixing unit includes a heating roller that generates heat at a high temperature and a pressure roller which is rotated in contact with a predetermined pressing force on the heating roller.

The above-mentioned heating roller generally arrange | positions a halogen lamp etc. as a heat source in the inside of a metal shaft, and performs fixation by heat transfer from the inside. However, in this case, there is a problem that the heat transfer loss is large because the distance between the heat source and the roller surface is large, and thus the power consumption of the heat source is large.

Therefore, in recent years, a fixing roller has been developed in which an electric resistance heating element layer is disposed near the surface of the roller to allow current to flow through and the fixing is performed using the heat generated by the electric resistance heating element layer as a heat source.

1 is a cross-sectional view showing the configuration of a heating roller of a fixing unit for an image forming apparatus according to the related art.

Referring to FIG. 1, the heating roller 10 includes an outer pipe 11, a heating coil 12, inner and outer insulating layers 13 and 14, and an inner pipe 15.

The heat generating coil 12 electrically generates heat to heat the developer phase formed on the recording medium. A resistance heat generating coil is used, and power is supplied through the terminals 16 provided at both ends of the outer pipe 11.

The outer pipe 11 is made of an aluminum pipe having high thermal conductivity, and a Teflon coating layer 17 is formed to prevent the toner from sticking to the surface thereof.

  The inner and outer insulating layers 13 and 14 are used to prevent the current of the heating coil 12 from being transferred to the surface of the outer pipe 11 so as not to damage the user, and are made of a mica layer.

The inner pipe 15 is also made of an aluminum pipe having high thermal conductivity. The inner pipe 15 includes an inner structure S, that is, the heating coil 12 and the inner and outer insulating layers 13 and 14 described above. The device in close contact with (11) has a predetermined expansion force. Here, the inner pipe 15 is in close contact with the outer pipe 11 and the inner structure without an air gap, so that heat generated in the heating coil 12 is not lost, but is transmitted to the outer pipe 11 to improve heat transfer efficiency. Let's go. In addition, the inner pipe 15 also serves to prevent the slip of the inner structure S from occurring by bringing the inner structure S into close contact with the inside of the outer pipe 11 with a predetermined expansion force.

However, conventionally, the expansion force of the inner pipe 15 may be reduced by the repeated thermal expansion operation of the heating coil 12, in which case the slip of the inner structure S slips from the outer pipe 11. Symptoms may occur.

When the slip of the internal structure (S) occurs, the distortion of the heating coil 12 fixed at both ends occurs, the heating coil 12 is disconnected to generate a coil spark or a low heat error (LOW HEAT ERROR) occurs .

The present invention has been proposed to solve the above problems, and an object of the present invention is to provide a heating roller that eliminates the occurrence of slip in the interior of the outer pipe of the inner structure including the heating coil.

Still another object of the present invention is to provide an image fixing apparatus using the above-described heating roller.

According to an embodiment of the present invention for achieving the above object, the outer pipe is formed of a high thermal conductivity material, the Teflon layer is coated on its outer surface; A primer layer provided inside the outer pipe; An outer insulating layer provided inside the primer layer; A heating coil provided inside the outer insulating layer; An inner insulation layer provided inside the heating coil; And an inner pipe provided inside the inner insulation layer, the inner pipe having a predetermined expansion force, and having a predetermined expansion force.

The inner and outer insulating layers are preferably Mica layers.

The primer layer may be made of an enamel material, and the enamel material may be any one of polyamide, polyimide, AIW (polyamideimide), and urethane.

The primer layer may alternatively be based on black painting.

The heating coil is preferably a nickel-chromium layer.

Preferably, the primer layer has a thickness of 50 μm or less, and the primer layer includes a Si component, and is preferably bonded at a high temperature with the Si resin component contained in the mica layer.

The inner and outer pipes preferably use aluminum pipes.

According to another embodiment of the present invention, an outer aluminum pipe having a Teflon layer formed on an outer surface thereof; A primer layer provided inside the outer aluminum pipe; An outer insulating layer provided inside the primer layer; A heating coil provided inside the outer insulating layer; An inner insulation layer provided inside the heating coil; And an inner aluminum pipe provided inside the inner insulation layer and having a predetermined expansion force. And a pressure roller contacting the heating roller at a predetermined pressure to form a fixing nip.

 The inner and outer insulating layers are preferably Mica layers.

The primer layer may be made of an enamel material, and the enamel material may be any one of polyamide, polyimide, AIW (polyamideimide), and urethane.

The primer layer may alternatively be based on black painting.

The heating coil is preferably a nickel-chromium layer.

The thickness of the primer layer is preferably formed to 50㎛ or less, the primer layer comprises a Si component, it is preferable to be bonded at a high temperature with the Si resin component contained in the mica layer.

The inner and outer pipes preferably use aluminum pipes.

According to another embodiment of the present invention, the above-described heating roller; And a pressure roller contacting the heating roller at a predetermined pressure to form a fixing nip.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a diagram showing an example of an image forming apparatus applied to the present invention. The operation of the image forming apparatus will be described with reference to FIG. 2 as follows.

Referring to FIG. 2, the photosensitive drum 211 is driven to rotate in a predetermined direction. The photosensitive drum 211 is charged to a predetermined polarity and potential by the primary charging roller 213 which is a charging unit in the rotation process. A predetermined light, for example a laser beam, is scanned from the light scanning unit 130 on the surface of the charged photosensitive drum 211 to form an electrostatic latent image.

The electrostatic latent image formed on the photosensitive drum 211 is developed and visualized by a developer through a developing roller 215 which is a developing unit.

On the other hand, by the drive of the paper feed roller 141, the recording medium 145 contained in the paper feed cassette 143 is supplied in a sheet and supplied to the photosensitive drum 211 side. The supplied recording medium 145 is supplied to a nip NIP, which is a contact point of the photosensitive drum 211 and the transfer roller 147, and the developer image of the photosensitive drum 211 is sequentially on the surface of the recording medium 145. Is transferred.

Thereafter, the recording medium 145 to which the developer image is transferred is thermally fixed while passing between the heating roller 210 and the pressure roller 230 which are the fixing units 200.

The recording medium 145 passing through the fixing unit 200 is discharged to the discharge tray 181 provided outside the apparatus main body 101 through the discharge unit 170.

3 is a cross-sectional view showing the configuration of a heating roller according to an embodiment of the present invention.

Referring to FIG. 3, the heating roller 210 includes an outer pipe 211, a primer layer 212, a heating coil 213, inner and outer insulating layers 214 and 215, and an inner pipe 216.

The outer pipe 211 is made of, for example, aluminum pipe having high thermal conductivity, and an outer surface of the outer pipe 211 is coated with a teflon layer 217 to prevent toner from sticking.

The primer layer 213 has an internal structure H, that is, the internal structure H with a strong adhesive force in order to eliminate the internal and external insulating layers 214 and 215 including the heating coil 213 from slipping from the inside of the outer pipe 211. ) Is fixed to the inner surface of the outer pipe 211.

The primer layer 212 may be made of an enamel material, for example, polyamide, polyimide, AIW (polyamideimide), or urethane. Alternatively, the primer layer 212 may be based on black painting.

The primer layer 212 including the Si component is preferably bonded to the Si resin component contained in the outer insulating layer 215 made of the mica layer at a high temperature. Here, the primer layer 212 may use DY-39-051 A and DY-39-051 B of Dow Corning.

Here, it is preferable that the thickness of the primer layer 212 is 50 micrometers or less, for example. This is to minimize heat loss of the heating coil 213.

The heating coil 213 is a resistance heating coil is used, is connected to the terminal (not shown) is supplied with power. The material of the heating coil is made of nickel-chromium, for example.

The inner pipe 216 is made of a high thermal conductive aluminum pipe like the outer pipe 211. The inner pipe 216 is plastically processed to have a predetermined expansion force. By the expansion force described above, the inner and outer insulating layers 214 and 215 including the inner structure H, that is, the heating coil 213, are brought into close contact with the inner wall of the outer pipe 211. The primer layer 212 adheres the inner structure H to the inside of the outer pipe 211 by a chemical change, and the inner pipe 216 connects the inner structure H to the outer pipe 211 by physical force. Fix it tightly inside. Therefore, when the heating roller 210 is rotated at a predetermined speed, the phenomenon in which the inner structure H slips from the inner surface of the outer pipe 211 can be effectively prevented.

Table 1 below shows the results of the accelerated test on the mono laser beam printer and the color printer by applying the heating roller 210 as described above.

Trial set The number of prints Resistance change before and after acceleration test (Ω) Internal slip occurrence  Mono laser beam printer #One 100,000 sheets 44.1 → 44.2 radish #.2 100,000 sheets 44.3 → 44.3 radish # .3 100,000 sheets 44.6 → 44.6 radish #.4 100,000 sheets 44.4 → 44.3 radish   Color printer # .5 9.5 million 40.1 → 40.2 radish # .6 100,000 sheets 40.3 → 40.3 radish # .7 100,000 sheets 40.1 → 40.1 radish #.8 100,000 sheets 40.5 → 40.5 radish

TABLE 1

As can be seen from Table 1, as a result of inspecting the resistance change by rotating the heating roller to 100,000 print sheets, there was almost no resistance change, and therefore, the slip of the internal structure H did not occur. Could.

As described above, the present invention can eliminate the slip of the internal structure according to the rotational operation of the heating roller by attaching the internal structure internal to the inside of the outer pipe constituting the heating roller using the primer layer. There is an advantage.

As described above, in the detailed description of the present invention, specific embodiments have been described, but various modifications may be made without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined not only by the claims below but also by the equivalents of the claims.

Claims (20)

An outer pipe formed of a high thermal conductivity material and having a Teflon layer coated on its outer surface; A primer layer provided inside the outer pipe; An outer insulating layer provided inside the primer layer; A heating coil provided inside the outer insulating layer; An inner insulation layer provided inside the heating coil; And And a high thermal conductivity inner pipe provided inside the inner insulating layer and having a predetermined expansion force. The heating roller of claim 1, wherein the outer insulating layer is a mica layer. The heating roller of claim 1, wherein the inner insulation layer is a mica layer. The heating roller of claim 1, wherein the primer layer is made of an enamel material. The heating roller according to claim 4, wherein the enamel material is any one of polyamide, polyimide, AIW (polyamideimide), and urethane. The heating roller of claim 1, wherein the primer layer is a black coating layer. The heating roller of claim 1, wherein the heating coil is a nickel-chromium layer.  The heating roller of claim 1, wherein the primer layer has a thickness of 50 μm or less. The heating roller of claim 2, wherein the primer layer comprises a Si component and is bonded at a high temperature with the Si resin component contained in the mica layer.  The heating roller of claim 1, wherein the outer pipe is an aluminum pipe. The heating roller of claim 1, wherein the inner pipe is an aluminum pipe. An outer aluminum pipe having a Teflon layer formed on an outer surface thereof; A primer layer provided inside the outer aluminum pipe; An outer insulating layer provided inside the primer layer; A heating coil provided inside the outer insulating layer; An inner insulation layer provided inside the heating coil; And an inner aluminum pipe provided inside the inner insulation layer and having a predetermined expansion force. And And a pressure roller in contact with the heating roller at a predetermined pressure to form a fixing nip. The image fixing apparatus according to claim 12, wherein the outer insulating layer is a mica layer. The image fixing apparatus according to claim 12, wherein the inner insulation layer is a mica layer. The image fixing apparatus according to claim 12, wherein the primer layer is made of an enamel material. The phase fixing apparatus according to claim 15, wherein the enamel material is any one of polyamide, polyimide, AIW (polyamideimide), and urethane. The image fixing apparatus according to claim 12, wherein the primer layer is a black coating layer. The image fixing apparatus according to claim 12, wherein the heating coil is a nickel-chromium layer. The image fixing apparatus according to claim 20, wherein the primer layer has a thickness of 50 µm or less. The phase fixing apparatus of claim 13, wherein the primer layer comprises a Si component and is bonded at a high temperature with a Si resin component contained in the mica layer, which is the outer insulating layer.

Images