JPS5919979A - Fixation device - Google Patents

Abstract

PURPOSE:To discharge paper from between fixation rolls securely by delaying the stopping of the fixation rolls. CONSTITUTION:When a CPU5 sends out a print stop instruction owing to abnormality, a motor driving circuit 3 stops an AC motor 2 and the fix roll 7 also stop. In this case, a timer 4 operates at this timing for a determined time. Namely, the motor driving circuit 3 is to stop the AC motor 2 by the stop instruction from the CPU5, but the AC motor 2 operates continuously until the timer 4 reaches the specific time and the AC motor also stops the specific time later. The stopping of the fixation rolls 7 is delayed by this timer function several seconds behind the operation stopping of a recording device. Consequently, the paper is discharged from between the fixation rolls securely.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fixing device, and particularly to a fixing device for a recording device that performs fixing by driving a fixing roller with a motor.

In a conventional fixing device, when the operation of the recording device stops during a copy sequence or the like, the fixing roller in the fixing device also stops at the same time. In this case, when there is paper between the fixing rollers, in order to remove the paper from the fixing rollers, a manual switch is used to operate the motor that drives the fixing rollers, and then after the paper is ejected, the motor is stopped. However, in this case, you may forget to turn off the manual switch, and in that case, the motor that drives the fixing roller continues to rotate, so a recording device equipped with a self-diagnosis function will treat it as abnormal operation. be.

Another method is to unconditionally operate the fixing roller idly when the recording apparatus is rotated during pre-rotation, and then discharge the paper present between the fixing rollers. However, with this method, there is a risk that the image quality will deteriorate in areas that are in contact with the fixing roller or areas that have not yet been fixed until the recording device stops and starts operating again. When paper remains, the recording device must be operated to eject the paper between the fixing rollers. Furthermore, in the case of a thermal fixing device, when taking out the paper between the fixing rollers, it is possible to pull out the paper between the fixing rollers directly or rotate the fixing roller manually, but when the paper is pulled out, the paper The paper may become unusable due to cuts or wrinkles, and may come into contact with the heat fixing roller when rotated manually.

Furthermore, in the case of a pressure fixing device, several tons of pressure is applied to the fixing rollers, so it is difficult to pull out the paper present between the fixing rollers, and it is also difficult to rotate the fixing rollers manually.

Therefore, the present invention aims to eliminate such conventional drawbacks, and provides a fixing device that can reliably discharge the paper present between the fixing rollers and perform good fixing. purpose.

According to the present invention, in order to achieve this objective, a configuration is adopted in which when the recording operation stops, the motor is driven to automatically discharge the paper present between the fixing rollers.

The present invention will be described in detail below based on embodiments shown in the drawings.

In FIG. 1, the reference numeral 1 indicates a door switch, and if even one door of the recording apparatus is open, the door switch turns off and cuts off the power supply to the circuit connected to the subsequent stage. An AC converter 2 is connected in series with a motor drive circuit 3 between the power terminals, and this AC
The motor 2 is driven via a motor drive circuit 3 controlled by the CPU 5 to rotate the fixing roller 7.

Also, a timer 4 is connected in parallel with the motor drive circuit 3, and this timer 4 turns on the AC for a period determined by the timer.
Motor 2 is delayed and then stopped.

Further, a timer 4 is connected to one input terminal of an AND gate 8, and when the timer is activated, a signal is input to the AND gate. Also, when CPU 5 stops the recording device etc.
An error display signal is input to the other input terminal of the ND gate 8. The output of AND gate 8 is connected to error indicator 6.

In such a configuration, the motor drive circuit 3 is driven under the control of the CPU 5, thereby turning on and off the current flowing to the AC motor 2. As a result, the AC motor rotates or stops, and accordingly, the fixing roller 7 also rotates or stops, thereby performing a fixing operation. If some abnormality occurs and the CPU 5 issues a print stop command for the entire recording apparatus, the motor drive circuit 3 stops the AC motor 2 and the fixing roller 7 as well. In this case, the timer 4 operates in accordance with this timing and operates for a predetermined period of time. That is, as shown in FIG. 2 (A>VC), when the operation of the recording device stops at time T1, the timer 4 operates for a predetermined time t, and the fixing roller also operates for the predetermined time. At the same time, the timer 4 operates the AC motor 2 for a predetermined time. After the predetermined time elapses, the AC motor 2 will stop. Therefore, the motor drive circuit 3 attempts to stop the AC motor 2 by receiving a stop command from the CPU. The AC motor 2 itself operates until the timer 4 expires for a predetermined time, and then the AC motor also stops after the predetermined time elapses.

Due to this timer function, the fixing roller 7 stops with a delay of several seconds when the operation of the recording apparatus stops.

Here, when the door switch 1 is turned off, the power that was being supplied to the fixing device is also no longer supplied. That is, when a jam occurs, the door is opened with an error message, and the door switch is turned off, the operation of the fixing device is unconditionally stopped and turned off. If the door is opened with an error message, the fixing roller 7 is turned off with a delay. It becomes impossible to stop it. Therefore, as shown in ) in FIG. 2, an error is displayed with a delay of a predetermined time of the error display timer 4.

This is accomplished as follows. That is, when an error occurs in FIG. 1, the error display signal is sent from the CPU 5 to AN.
It is input to the error indicator 6 via the D gate 8. This AND gate logically ANDs the output of the timer 4 and the output of the CPU and outputs it to the error indicator 6. Therefore, the error indicator 6 displays an error at the timing shown in ) in FIG. That is, when an error occurs, the fixing roller rotates with a delay for the predetermined time set by the timer 4, the recording apparatus stops, and an error message is displayed.

In the above embodiment, a bimetallic delay relay may be used instead of the timer, and when the motor drive circuit stops the AC motor, current may be passed through the bimetallic delay relay to control the AC motor to be stopped after a certain period of time has elapsed. . In that case, when the motor drive circuit drives the AC motor 2, the bimetallic delay relay is brought into the reset state to operate the AC motor. Furthermore, an electromagnetic timer or the like may be used instead of the bimetallic delay relay.

In addition, an element that can be used as a timer or the like is inserted into the motor drive circuit to provide a delay between when the motor drive circuit receives the command to stop the AC motor 2 and when it actually stops, or to delay the ACC morph stop command itself by the CPU, etc. It is also possible to consider a method such as outputting the data in a delayed manner. In addition, when the motor for operating the fixing roller also serves as a motor for another function, the motor is coupled only to the fixing roller using an electromagnetic clutch or the like only when a stop command is issued.

Furthermore, although the AC motor has been described, it is not limited thereto.
The same can be said for the C motor. Further, according to the present invention, if there is a function such as a fixing roller that requires a delay and is to be stopped for 10 minutes, it can be used in conjunction with that function.

Furthermore, in the above-mentioned embodiment, after a stop command is received, the fixing roller is stopped with a delay, an error message is displayed, and the door switch is turned off. However, if a separate stop command is received, the fixing roller is also stopped immediately. At the same time, an error display may be displayed, and even if the door switch is turned off, as soon as the side door switch is turned on, the fixing roller may be operated unconditionally for several seconds regardless of whether there is any subsequent printing. In addition, the power supply to the fixing device may be stopped after a predetermined time delay even when the door switch is turned off. It can also be used as a backup power source.

Further, as a method of delaying the error display, a method similar to the method of delaying the stoppage of the fixing roller may be used. That is, it is also possible to use a display method with a delay using a timer, bimetal, or CPU software.

As explained above, according to the present invention, when the fixing roller stops, it is stopped with a delay, so even if there is paper between the fixing rollers, it is automatically and surely removed. can be discharged. As a result, when the operation of the recording apparatus is stopped due to an error or the like, for example, it is possible to avoid treating the paper present between the fixing rollers as a misprint. Furthermore, since the error display is delayed, it is also possible to perform self-diagnosis using the predetermined time.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a schematic configuration of the fixing device of the present invention, and FIGS. 2(A) to (Di are timing charts explaining the operation of the device shown in FIG. 1. 1... Door switch 2 ...AC motor 3.
...Motor drive circuit 4...Timer 5...CP
U 6...Error indicator 7...Fusing roller

Claims (3)

[Claims] (1) In a fixing device for a recording device that uses a motor to drive the fixing roller to perform fixing, when the recording device stops operating, the motor is driven to automatically eject the paper present between the fixing rollers. A fixing device characterized by: (2) The fixing device according to claim 1, wherein the fixing roller is driven for a predetermined period of time when the operation of the recording device is stopped. (3) The fixing device according to claim 1 or 2, wherein an error display is performed after the fixing roller stops.