JPH0658582B2 - Fixing device temperature control method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing device temperature control method, and more particularly to a fixing device temperature control method when a paper jam occurs.

<Prior Art> Conventionally, a copying machine that employs a heat roller fixing method has been widely used. When a paper jam is detected in the middle of a paper feeding path, a copying paper conveying operation and an optical system document exposure are performed. The operation and the image forming operation of the copy processing unit are stopped. Regarding the temperature of the fixing device, a method of continuously maintaining the set temperature at which copying operation is possible and a method of completely cutting off the power supply to the fixing heater incorporated in the heat roller are adopted.

<Problems to be Solved by the Invention> According to the method described above, there is no inconvenience with respect to a paper jam in a portion other than the fixing device, but the fixing device continues to be kept at a set temperature at which copying operation is possible. Therefore, if a paper jam occurs in the fixing device,
If the copy paper is abnormally heated and the jammed copy paper is not removed for a long time, a fire may occur, and the operator may be burned.

Further, according to the above method, even if the copying paper is not removed for a long time after the fixing device is clogged with the copying paper, there is no possibility of causing a fire, but the copying paper was not removed for a long time. In this case, the temperature of the fixing device drops to a temperature close to room temperature. Therefore, when the copying operation is restarted after that, it takes a long time for the temperature of the fixing device to rise to the set temperature at which the copying operation can be performed. There is an inconvenience. In particular, even if the copy paper is jammed at a place other than the fixing time, there is no danger of a fire,
Since the temperature of the fixing device continues to drop until the jammed copy paper is removed, when restarting the copying operation, it takes a long time for the temperature of the fixing device to rise to the set temperature at which the copying operation can be performed as described above. There is an inconvenience that it is necessary.

This invention has been made in view of the above problems,
A temperature control method for a fixing device in which there is no risk of a fire even if a paper jam occurs in the fixing device, and moreover, it is possible to return to a state in which a copying operation can be performed in a short time after removing the jammed copying machine. It is intended to be provided.

<Means for Solving Problems> In order to achieve the above object, the temperature control method of the fixing device of the present invention determines whether a paper jam of the device or a paper jam of a portion other than the fixing device occurs. However, if it is determined that the fixing device has a paper jam, the temperature of the fixing device is controlled to be lower than the set temperature during preheating and higher than room temperature, and the temperature of the parts other than the fixing device is controlled. When it is determined that the paper is jammed, the temperature of the fixing device is controlled to the preset temperature at the time of preheating.

<Operation> When a paper jam occurs in the fixing device, the copy paper makes an abnormal noise, and if the jammed copy paper is not removed for a long time, a fire may occur or the operator may May cause burns.

According to the above temperature control method, when the paper jam in the fixing device is detected, the temperature of the fixing device is maintained at the set temperature lower than the set temperature at the time of preheating and higher than the room temperature. Therefore, even if the jammed copy paper is not removed for a long time without completely interrupting the power supply to the fixing device, the copy paper does not abnormally heat up. As a result, there is no risk of a fire occurring and the operator being injured, and in addition, it is possible to shorten the time from the removal of the paper jam of the fixing device to the restart of the copying operation.

On the other hand, when the copy paper is jammed at a place other than the fixing device, there is no risk of occurrence of fire or the like like the paper jam in the fixing device.

According to the above temperature control method, when a paper jam is detected at a place other than the fixing device, the temperature of the fixing device is maintained at the set temperature during preheating. As a result, the temperature of the fixing device in which no paper jam has occurred does not drop more than necessary, and the time until the copying operation is restarted can be shortened.

<Example> Hereinafter, detailed description will be given with reference to the accompanying drawings illustrating an example.

The drawing is a flowchart showing an embodiment of a temperature control method for a fixing device.

In step, it is determined whether or not the paper jam of the fixing device and the paper jam of the portion other than the fixing device in the paper feeding path have occurred. If it is determined that the paper jam does not occur at all, it is determined whether or not the copying operation is being performed in the step. It is determined whether or not there is, and if it is equal to or higher than the set temperature, the energization to the fixing heater is cut off in the step, and if it is lower than the set temperature, the fixing heater is energized in the step to raise the temperature of the fixing device.

If it is determined in step that the fixing device has a paper jam, it is determined in step whether or not the temperature is equal to or higher than the preset temperature lower than the preset temperature at the time of preheating. Done,
If it is lower than the set temperature, step processing is performed. If it is determined in step that the paper is jammed in a place other than the fixing device, it is determined in step whether or not the temperature is equal to or higher than the preset temperature at the time of preheating, and if the temperature is equal to or higher than the preset temperature, the process of step is performed. If the temperature is lower than the set temperature, step processing is performed. Then, after performing the step or the processing of the step, in the step, it is determined whether or not a predetermined time has passed after the paper jam is detected. The process is performed, but if the predetermined time has passed, the temperature control of the fixing device is ended by cutting off the power supply to the fixing heater in step.

Therefore, when a paper jam occurs, the temperature control of the fixing device differs depending on whether the paper jam of the fixing device or not. That is, to explain in more detail, if the paper jam of the fixing device, the fixing device is controlled to a set temperature lower than the set temperature at the time of preheating and higher than room temperature, and if the paper is jammed at a place other than the fixing device, The fixing device is controlled to the preset temperature at the time of preheating, and when the paper jam does not occur at any place, if the copying operation is being performed, the fixing temperature is controlled to the setting temperature at which the copying operation can be performed. If not, the temperature can be controlled to the set temperature during preheating. Here, when a paper jam occurs in the fixing device, it is necessary to control the temperature of the fixing device to be lower than the preset temperature at the time of preheating and higher than room temperature. Even if the set temperature during preheating is maintained, if the copy paper temperature rises abnormally and the jammed copy paper is not removed for a long time, a fire may occur or the operator may be burned. This is because there is a fear.

According to the above temperature control method, when the paper jam in the fixing device is detected, the temperature of the fixing device is maintained at the set temperature lower than the set temperature at the time of preheating and higher than the room temperature. Therefore, even if the jammed copy paper is not removed for a long time without completely interrupting the power supply to the fixing device, the copy paper does not abnormally heat up. As a result, there is no risk of a fire occurring or the operator being injured, and in addition, it is possible to shorten the time from the removal of the paper jam of the fixing device to the restart of the copying operation.

On the other hand, when a paper jam in the paper feeding unit is detected, the fixing temperature is maintained at the set temperature during preheating. As a result, the temperature of the fixing device in which no paper jam has occurred does not drop more than necessary, and the time until the copying operation is restarted can be shortened.

In summary, the temperature of the fixing device can be controlled according to the location where the paper jam occurs, and abnormal temperature rise and fire can be reliably prevented, and the temperature of the fixing device can be quickly changed when copying operation is restarted. Therefore, the waiting time can be shortened because the setting time can be increased to the time when copying operation is possible.

The present invention is not limited to the above-described embodiment. For example, when a paper jam occurs in the fixing device, first, the temperature of the fixing device is controlled to the set temperature during preheating, and after a predetermined time elapses. May be controlled to a temperature lower than the preset temperature at the time of preheating and higher than room temperature, and various other setting changes can be made without changing the gist of the present invention.

<Effects of the Invention> As is apparent from the above description, according to the present invention, when the temperature of the fixing device is controlled corresponding to the position where the paper jam occurs, and when the paper jam in the fixing device is detected, The temperature of the fixing device is kept lower than the set temperature during preheating and higher than the room temperature, and when a paper jam at a place other than the fixing device is detected, the fixing temperature is set at the time of preheating. Maintained at set temperature.

As a result, it is possible to reliably prevent the abnormal temperature rise of the copy paper and the occurrence of a fire, and it is possible to return to a state where the copy operation can be performed in a short time after removing the jammed copy paper. Play.

[Brief description of drawings]

The drawing is a flow chart showing an embodiment of a temperature control method for a fixing device.

Claims (1)

[Claims] 1. A paper jam of a fixing device and a paper jam of a part other than the fixing device are determined, and when it is determined that the paper jam of the fixing device is detected, the temperature of the fixing device is changed to When it is determined that the paper temperature is lower than the set temperature during preheating and higher than room temperature, and it is determined that there is a paper jam in a part other than the fixing device, the temperature of the fixing device is changed to the set temperature during preheating. A method for controlling the temperature of a fixing device, which is characterized in that the temperature of the fixing device is controlled.