JPH103225A - Fixing device - Google Patents

Abstract

(57) [Problem] To improve the fixing efficiency by reducing standby time and power consumption until a set mode reaches a set temperature, and to cause a fixing defect on an object to be fixed. To provide no fusing device. A fixing device includes a fixing roller, a pressure roller provided to face the fixing roller,
A temperature control means for detecting the temperature of the fixing roller 1 and controlling the temperature of the fixing roller 1 is provided independently in the axial direction and the circumferential direction between the core of the fixing roller 1 and the surface coating layer 6. The heating wires 8 and 9 which are provided and are corrugated are arranged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing device.

[0002]

2. Description of the Related Art A typical conventional fixing device is disclosed in (1) Japanese Patent Application Laid-Open No. 3-44682, which will be described with reference to FIG. .
It includes a fixing roller 21 having a non-contact type fixing heater 22 installed therein, a pressure roller 23 provided opposite to the fixing roller 21, a temperature sensor 24 for detecting the temperature of the fixing roller 21, A temperature control means 25 is provided which receives a temperature from the temperature sensor 24, controls the temperature of the fixing roller 21 by comparing the temperature with a set temperature.

Next, as another type of fixing device,
(2) There is one disclosed in Japanese Patent Laid-Open No. 4-213480, which will be described with reference to FIG. The fixing roller 31 is provided with a heating element 32 that is bent in the circumferential direction and extends in the axial direction.The power supply brush 33 is arranged in a limited manner to supply power only to the heating element 32 necessary for fixing, and partially fix the fixing roller 31. To be heated.

[0004]

In the fixing device as described in the above (1), a fixing roller is provided for each operation state.
Since the temperature of 21 is changed and used by the temperature control means 25, if the amount of change in the set temperature is large, the apparatus may start until the set mode reaches the set temperature. Therefore, there is a problem that wasteful standby time and power consumption are required, and the fixing efficiency is poor. In the fixing device as described in (2), the problem of the fixing device as in (1) can be solved. However, since the heating element 32 is configured to extend only in the axial direction, In order to keep the entire fixing roller 31 at a uniform temperature, the circumferential distance between the heating elements 32 must be close, which is inefficient in terms of power consumption, and the heating elements 32 required for fixing are not required. Only the power is supplied, and the fixing roller 31 is partially heated, so that the fixing object reaches the fixing roller 31 before the surface temperature of the fixing roller 31 reaches the set temperature depending on the setting conditions. Thus, there is a problem that a fixing failure occurs.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems of the conventional fixing device, and reduce the standby time and power consumption until the set mode reaches the set temperature, thereby improving the fixing efficiency. An object of the present invention is to provide a fixing device which is excellent and does not cause a fixing defect on a fixing object.

[0006]

According to the present invention, there is provided a fixing apparatus for achieving the above object.
The present invention provides a fixing device including a fixing roller, a pressure roller provided opposite to the fixing roller, and a temperature control unit that detects a temperature of the fixing roller and controls a temperature of the fixing roller. Wherein a heating wire which is provided independently in the axial direction and the circumferential direction and is corrugated is disposed between the core of the fixing roller and the surface coating layer. According to a second aspect of the present invention, in the first aspect, a current is constantly supplied to the heating wire, and the temperature of the fixing roller is kept constant by a temperature control unit.

According to a third aspect of the present invention, in the first aspect of the invention, when the temperature of the fixing roller reaches a set temperature, the supply of current to the heating wire is temporarily stopped, and the temperature of the fixing roller is reduced. An electric current is supplied to the heating wire when the temperature becomes lower than the set temperature. The invention according to claim 4 is such that in the invention according to claim 3, the temperature of the fixing roller is lower than the set temperature. When the temperature rises by 1% or more, the supply of the current to the heating wire is temporarily stopped, and when the temperature of the fixing roller falls by 1% or more from the set temperature, the current is supplied to the heating wire.

According to a fifth aspect of the present invention, in the first aspect of the invention, a current is alternately supplied to the heating wires in the axial direction and the circumferential direction, and the temperature of the fixing roller is kept constant by the temperature control means. It is characterized by holding.

According to a sixth aspect of the present invention, in the fifth aspect of the present invention, when the temperature of the fixing roller reaches a set temperature, a current is supplied to one of the heating wires in the axial direction and the circumferential direction. The invention according to claim 7, wherein the supply is temporarily stopped, and when the temperature of the fixing roller becomes lower than a set temperature, the current is supplied to the heating wire for which the supply of the current is temporarily stopped. In the invention according to the sixth aspect, when the temperature of the fixing roller is higher than the set temperature by 1% or more, the supply of the current to one of the heating wires in the axial direction and the circumferential direction is temporarily stopped, When the temperature of the fixing roller is lower than the set temperature by 1% or more, the current is supplied to the heating wire for which the supply of the current is temporarily stopped.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In a first embodiment of the present invention shown in FIGS. 1 to 3, a core 4 of a fixing roller 1 and a surface coating layer 6 are provided.
The intermediate sheet 7 is interposed between the intermediate sheet 7 and the intermediate sheet 7.
The heating wires 8 and 9 are provided independently in the axial direction and the circumferential direction.

In such a case, current is always supplied to the heating wires 8 and 9 of the intermediate sheet 7, and the temperature of the fixing roller 1 reaches the temperature set by the temperature sensor 3 by the temperature sensor 3 by the temperature sensor 3. When it is detected, the supply of current to the heating wires 8, 9 of the intermediate sheet 7 is temporarily stopped,
When the temperature of the fixing roller 1 becomes lower than the set temperature, a current is supplied to the heating wires 8 and 9 to keep the temperature of the fixing roller 1 constant.

At this time, in order to keep the temperature of the fixing roller 1 constant, the upper and lower limits of the temperature of the fixing roller 1 are set to 1% of the set temperature, and when the detected temperature becomes higher than the set temperature by 1% or more, the intermediate sheet is set. The supply of the current to the heating wires 8 and 9 is temporarily stopped, and when the temperature becomes lower than the set temperature by 1% or more, the current is supplied to the heating wires 8 and 9.

Next, although not shown, the second embodiment of the present invention
The second embodiment differs from the first embodiment in that current is alternately supplied to the heating wires 8 and 9 in the axial direction and the circumferential direction of the intermediate sheet 7.

In such an embodiment, when the temperature of the fixing roller 1 reaches the set temperature, current is supplied to one of the heating wires 8 and 9 in the axial direction and the circumferential direction of the intermediate sheet 7. Is temporarily stopped, and when the temperature of the fixing roller 1 becomes lower than the set temperature, the current is supplied to the heating wire 8 or 9 for which the supply of the current is temporarily stopped, and the temperature of the fixing roller 1 is kept constant.

At this time, in order to keep the temperature of the fixing roller 1 constant, the upper and lower limits of the temperature of the fixing roller 1 are set to 1% of the set temperature, and when the detected temperature becomes higher than the set temperature by 1% or more, the intermediate sheet The supply of current to one of the heating wires 8 and 9 is temporarily stopped, and when the temperature becomes lower than the set temperature by 1% or more, the supply of current to the heating wire 8 or 9 is temporarily stopped.
To supply current.

[0016]

The present invention is as described above. In the fixing device, the invention according to claims 1 and 2 is characterized in that the axial direction and the circumferential direction are located between the core of the fixing roller and the surface coating layer. The heating wires are provided independently of each other and have a corrugated shape, so that the waiting time and power consumption until the set mode reaches the set temperature are reduced, and the fixing efficiency is good. In addition, there is an effect that the fixing failure does not occur on the fixing object.

According to a second aspect of the present invention, in the first aspect of the invention, a current is constantly supplied to the heating wire and the temperature of the fixing roller is kept constant by the temperature control means.
There is an effect that the power supply voltage can be prevented from dropping due to the rush current.

According to a third aspect of the present invention, in the first aspect, when the temperature of the fixing roller reaches a set temperature, the supply of current to the heating wire is temporarily stopped, and the temperature of the fixing roller is reduced. When the temperature is lower than the set temperature, a current is supplied to the heating wire, so that there is an effect that power consumption can be reduced.

According to a fourth aspect of the present invention, when the temperature of the fixing roller becomes higher than the set temperature by 1% or more, the supply of the current to the heating wire is temporarily stopped. The temperature of the fixing roller is 1
%, The current is supplied to the heating wire, so that the surface temperature of the fixing roller can be maintained in an optimal and stable state, and the voltage drop due to the inrush current generated by turning off / on can be reduced. effective.

According to a fifth aspect of the present invention, in the first aspect of the invention, current is alternately supplied to the heating wire in the axial direction and the circumferential direction, and the temperature of the fixing roller is kept constant by the temperature control means. Since the holding is performed, it is possible to prevent heat from concentrating at the intersection of the heating wires more than at other portions, thereby preventing damage to the surface of the fixing roller in contact with the intersection.

According to a sixth aspect of the present invention, in the fifth aspect of the invention, when the temperature of the fixing roller reaches the set temperature, the current is supplied to one of the heating wires in the axial direction and the circumferential direction. When the supply is temporarily stopped and the temperature of the fixing roller becomes lower than the set temperature, the current is supplied to the heating wire for which the supply of the current has been temporarily stopped. Is supplied, the surface temperature of the fixing roller can be maintained.

According to a seventh aspect of the present invention, in the invention according to the sixth aspect, when the temperature of the fixing roller becomes higher than the set temperature by 1% or more, the heat is applied to one of the heating wires in the axial direction and the circumferential direction. Is temporarily stopped, and when the temperature of the fixing roller becomes lower than the set temperature by 1% or more, the current is supplied to the heating wire for which the supply of the current is temporarily stopped. Has the effect that the surface temperature of the substrate can be efficiently brought close to the target value.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part of a first embodiment of the present invention.

FIG. 2 is a partially cutaway perspective view of the same.

FIG. 3 is a vertical sectional front view of the same.

FIG. 4 is a perspective view of a conventional fixing device of the same type as the present invention.

FIG. 5 is a perspective view of a fixing roller of another conventional fixing device of the same type as the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fixing roller 2 Pressure roller 3 Temperature sensor 4 Core body 6 Surface coating layer 7 Intermediate sheet 8 Heating wire 9 Heating wire

Claims (7)

[Claims] 1. A fixing device comprising: a fixing roller; a pressure roller provided to face the fixing roller; and a temperature control means for detecting the temperature of the fixing roller and controlling the temperature of the fixing roller. A fixing device, wherein a heating wire that is provided independently in the axial direction and the circumferential direction and that has a corrugated shape is disposed between the core of the fixing roller and the surface coating layer. . 2. The fixing device according to claim 1, wherein a current is constantly supplied to the heating wire, and the temperature of the fixing roller is kept constant by a temperature control unit. 3. When the temperature of the fixing roller reaches a set temperature, the current supply to the heating wire is temporarily stopped, and when the temperature of the fixing roller becomes lower than the set temperature, the current is supplied to the heating wire. The fixing device according to claim 1, wherein: 4. The fixing roller according to claim 1, wherein the temperature of the fixing roller is lower than the set temperature by one.
The current supply to the heating wire is temporarily stopped when the temperature rises by more than 1%, and the current is supplied to the heating wire when the temperature of the fixing roller becomes lower than the set temperature by 1% or more. Fixing device. 5. The fixing device according to claim 1, wherein a current is alternately supplied to the heating wires in the axial direction and the circumferential direction, and the temperature of the fixing roller is kept constant by the temperature control means. 6. When the temperature of the fixing roller reaches the set temperature, the supply of current to one of the heating wires in the axial direction and the circumferential direction is temporarily stopped, and the temperature of the fixing roller becomes lower than the set temperature. The current is supplied to the heating wire, the supply of which is temporarily stopped.
3. The fixing device according to claim 1. 7. The fixing roller according to claim 1, wherein the temperature of the fixing roller is lower than the set temperature by one.
%, The supply of the current to one of the heating wires in the axial direction and the circumferential direction is temporarily stopped. When the temperature of the fixing roller becomes lower than the set temperature by 1% or more, the supply of the current is temporarily stopped. 7. The fixing device according to claim 6, wherein a current is supplied to the stopped heating wire.