JPS5967567A - Heat fixation roll - Google Patents

Abstract

PURPOSE:To obtain a heat fixation roll which has a shortened start time by using titanium oxide for a resistance heating body. CONSTITUTION:An Al2O3 insulating layer 3 which is 200mum thick as the 1st layer, a titanium oxide resistor layer 4 which is 70mum thick as the 2nd layer, and a ''Teflon'' film 5 which is 20mum thick as an outermost layer are formed respectively on the surface of the fixation roll body 1. The electrodes 6a and 6b of the resistor are provided at both end parts of the ''Teflon'' film 5, and the fixation roll surface is heated by conducting a current from the electrodes 6a and 6b. A conventional halogen lamp method requires 750W powder to obtain 200 deg.C, but this invented fixation roll obtains 200 deg.C with 300W; when a 80V voltage is impressed between the electrodes 6a and 6b, the roll attains 200 deg.C in about 40sec and when 100V is applied, it takes about 20sec to obtain 200 deg.C to save electric power by about several ten %, and to improve a start characteristics to several times highen.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the structure of a heat fixing device used in electronic copying machines and the like, and particularly to improvements in the heating plate.

Conventionally, heating methods for heat-fixing rolls used in electronic copying machines and the like include: 1. A method in which an infrared lamp is housed in the roll body made of a metal cylinder with high thermal conductivity such as AI, and heating is performed from the inner wall of the roll; (2) A method has been used in which a heating section made of PTC ceramics is provided near the outer circumferential surface of the roll and heating is performed from near the outer circumferential surface of the roll.

However, method (2) above has the disadvantage that several minutes of warming-up time is required before starting, and the thermal efficiency is not high.

In addition, with method (2) above, it is difficult to produce 1q of PTCt laminated materials having a desired resistance rise temperature, and it is especially difficult to control the resistance value when forming a resistor film on the roll surface. He is a hard worker.

Therefore, for example, when the desired value is set to 200°C, the rise temperature of the resistor deviates from 200°C by about 5°C, causing the PT.
C ceramics [There are problems such as the impossibility of electrical heating.

The present invention has been carried out in order to improve the above-mentioned drawbacks of the prior art, and its main purpose is to realize a heat fixing roll with a shortened start time. Another object of the present invention is to provide a heat-fixing roll that can contribute to energy saving and facilitates the formation of resistors.

In order to achieve the above object, the present invention is characterized in that titanium oxide is used as the heating resistor material.

Titanium oxide has the advantage that it has high weather resistance, allows easy formation of a resistive layer or film, and can be used without problems even at temperatures of about 200° C. required for heat fixing. In general, when a titanium oxide resistor is used, rapid heating is possible, and the titanium oxide resistive layer or resistive film does not change during rapid heating. Furthermore, when using a titanium oxide resistor, there is an advantage that higher thermal efficiency can be obtained compared to the conventional infrared heating method.

The present invention will be described in detail below based on examples.

FIG. 1 is a partially sectional structural explanatory diagram showing an embodiment of the present invention. In the figure, reference numeral 1 denotes a fixing roll body made of a metal pipe such as iron, and has a rotating shaft 2. As shown in FIG. The surface of the fixing roll main body 1 has a thickness of 2 as a first layer.
A 00 μm thick Al2O3 insulating layer 3, a 70 μm thick titanium oxide resistor layer 4 as a second layer, and a 20 μm thick Teflon film 5 as the outermost layer are formed. Resistor electrodes 6 are provided at both ends of the outermost Teflon film 5.
a.

A current is passed through the electrodes 5a and 5b to heat the surface of the fixing roll.

In the heat fixing roll of the present invention having the above configuration, the electrode 6a,
200 by applying a voltage of 45V between 6+b
It was possible to obtain a surface temperature of °C.

With the conventional halogen lamp method, it is possible to obtain 200°C.
The heat fixing roll according to the present invention achieved a temperature of 200° C. with 300 W, whereas the heat fixing roll according to the present invention required 750 W, confirming that the present invention can realize an energy-saving heat fixing roll.

In addition, in this embodiment, 80V is applied between the electrodes 6a and 6b.
It was confirmed that the temperature reached 200° C. in about 40 seconds when a voltage of 200° C. was applied, and in about 20 seconds when a voltage of 100° C. was applied, which was a fraction of the time required by the conventional method.

(Details above) As mentioned above, the present invention has the advantage of saving several tens of percent of power and improving the starting characteristics several times. Further, in the present invention, the above-mentioned resistive film or resistive layer can be easily formed by thermal spraying, etc., and has the advantage of being excellent in mass production.

[Brief explanation of drawings]

FIG. 1 is a partially cross-sectional diagram illustrating the structure of a heat fixing roll showing an embodiment of the present invention. 1: Roll body, 2: Rotating shaft, 3: Insulating layer, 4: Resistance layer, 5: Teflon film, 6: Electrode. Figure l Amendment to the procedure June 13, 1980 Display of the case of the Commissioner of the Patent Office 1982 Patent application No. 172582 Title of the invention
Relationship with the case of a person who corrects heat-fixing rolls Patent applicant address 2-1-2 Marunouchi, Chiyoda-ku, Tokyo Name (5)
08) Contents of amendment in the "Detailed Description of the Invention" column of the Hitachi Metals Co., Ltd. Specification As shown in the attached sheet, the description in the "Detailed Description of the Invention-I" column of the description will be corrected as follows. . (1) "To change" in the 4th line of page 3 of the specification is corrected to "to be damaged." (2) In the same book, page 2, line 7, "deviation of approximately 5°C from 200°C" is corrected to "deviation of 5°C from 200°C." (3) "Thickness 20 μm" on page 3, line 15 of the same book is corrected to "thickness 30 μm J."

Claims (1)

[Claims] A heating fixing roll characterized by using titanium oxide as a resistance heating element.