JPH075793A - Abnormality detector for ozone exhausting fan - Google Patents

Abstract

PURPOSE:To provide an abnormality detector for a fan capable of surely preventing contamination by ozone even at such an abnormal time that a fan is stopped and also for discharging a transfer sheet which is on the process of forming an image from the machine. CONSTITUTION:In the case of preventing the ozone generated in the machine from being exhausted to the outside of the machine by use of an ozone exhausting fan 1 equipped with an ozone filter, the abnormal rotation of the ozone exhausting fan 1 is detected, and when the abnormality is detected, forming the image on the transfer sheet which is on the process of forming the image is ended, and the image forming device is stopped to be driven after the transfer sheet is discharged, so that the prevention of the contamination by the ozone is secured, and also, the transfer sheet which is on the process of forming the image is discharged from the machine, so that post processing such as a work for removing the transfer sheet remaining in the machine is reduced, and furthermore, the transfer sheet is prevented from being wasted unwittingly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an abnormality detecting device for a fan used in a copying machine, a printer, a facsimile, etc., for discharging ozone in the machine.

[0002]

2. Description of the Related Art Generally, a copying machine is provided with a charger and the like, and when the apparatus is in operation, its discharge operation (minus discharge or AC discharge) produces ozone, which is a harmful substance. There is a safety standard value for the amount of ozone generated in order to prevent environmental pollution. It is necessary to suppress the generation of ozone so that the amount of leakage of ozone to the outside becomes equal to or less than the reference value.

In this respect, in a copying machine or the like, the fan is constantly driven to rotate while the power is on, that is, during the operation, and the cooling and heat discharging operation for the heat generation of the exposure lamp is performed. And
Such a cooling fan is provided with an ozone filter, and the amount of ozone discharged to the outside is kept below a certain value by exhausting air through this ozone filter. However, if the cooling fan stops due to a failure of the cooling fan or disconnection of the wiring code of the cooling fan while the copier is operating, the exhaust will be only natural convection and the efficiency of the ozone filter will decrease. However, ozone generated due to discharge of the charging charger cannot be efficiently processed. If the copy operation is continued in such a state, the ozone generation amount may exceed the safety standard value. Therefore, Japanese Utility Model Application Laid-Open No. 01-157350 and Japanese Patent Application Laid-Open No. 01-177052 have been proposed. When an abnormality occurs in the cooling fan, an abnormality signal or the operation of the copying machine main body is stopped.

However, when the main body of the copying machine is immediately stopped due to the abnormality of the cooling fan, the transfer paper left in the main body is jammed paper even though the image formation was normally performed. Must be removed.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to prevent ozone contamination even when the fan is abnormally stopped and to effectively utilize the transfer paper left in the main body. An object is to provide a fan abnormality detection device.

[0006]

In order to achieve the above object, the present invention detects the abnormal rotation of a fan, at which point the image formation of the transfer sheet during image formation is completed and the transfer sheet is completed. The problem is solved by stopping the main body of the copying machine as soon as is discharged.

[0007]

Embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic perspective view showing an example of an abnormality detecting device for an ozone exhaust fan according to the present invention.

Ozone exhaust fan (hereinafter referred to as fan)
1, ozone or the like generated in the main body is sent through the first duct 2. Then, by the rotation of the fan 1, it passes through the second duct 3 and is discharged to the outside of the machine. The second duct 3 is equipped with an ozone filter 4, which keeps the amount of ozone discharged to the outside of the machine below a safety standard value.

The fan 1 has a light-shielding portion 5, and a reflecting portion 6 is provided on a part of the light-shielding portion 5. The bracket 10 provided above the fan 1 is provided with a hole 11 at a position through which the reflecting portion 6 passes by being rotated.

Then, a reflection type sensor 2 which emits a light ray from a light emitting portion (not shown), reflects it on the reflecting portion 6, and receives the light ray reflected by the reflecting portion 6 through the hole 11.
0 is provided above the bracket 10.

By the reflecting section 6 and the reflection type sensor 20,
The rotation speed of the fan 1 can be detected, and abnormal rotation drive of the fan 1 can be immediately detected.

As the abnormality detection of the fan 1, it is also possible to detect the abnormal rotation by detecting the drive current of the fan 1 and comparing it with a reference value.

FIG. 2 is a control block diagram according to the present invention.

The reflection type sensor 20 detects whether the fan 1 is rotating or not.
Is detected by the CPU (Center) in the main control unit
It is determined by the local processing unit (central processing unit) 30. If there is no abnormality here, the main body performs the drive operation as it is, but if it is determined to be abnormal, an abnormality display is displayed on the operation unit 31.

When it is determined to be abnormal, the transfer paper on which image processing is being performed in the machine is subjected to image formation (steps from transfer to fixing / paper discharge), and then the drive of the main body is stopped.

When this abnormality determination is made, the process at which the transfer paper is discharged is determined to be a process that can be processed within a time period in which ozone discharge does not exceed the safety standard value due to abnormal rotation. Specifically, at the time when this abnormality determination is made, only the visible material formed on the photoconductor is transferred to the transfer paper, and the fixing and discharging are performed. The transfer paper waiting by the registration roller located upstream of the photoconductor is left as it is and taken out as jam paper from the inside of the machine later, or when the fan 1 is normally driven and the drive of the main body is restored. Alternatively, it may be conveyed at the registration timing and used for image formation.

By thus processing the transfer paper in the machine, the transfer paper that has been normally transferred is ejected and the copying is completed, so that the transfer paper remaining in the machine is reduced and the transfer paper is wasted. do not become.

FIG. 3 is an operation flowchart of the detection control in the CPU.

Reference numeral 40 is for setting a stop judgment timer of the fan 1 for a certain period of time and checking the input of the sensor by interrupt control. That is, when a sensor input that rises from a low signal to a high signal is detected within a predetermined time set by the stop determination timer, it is determined by 41 that the drive is normal, the stop determination timer is reset, and the drive is continued as it is.

Reference numeral 42 sets the abnormality detection because the fan 1 is not driven due to some abnormality when the sensor input with the same level is detected in the stop determination timer even after a predetermined time. is there.

Then, 43 is the fan 1 by this 42.
It outputs a signal indicating the abnormal condition.

Further, by 44, the main body is stopped. At this time, this stop timing is performed after the transfer paper being image-formed is discharged as described above.

In the above, the abnormal drive is determined by determining whether the fan 1 is driven, but it is determined whether the rotation speed is normal, that is, whether the rotation is slower or faster than normal. The same is true.

Even if two or more fans are provided, it may be determined which fan is abnormal and control as described above.

Further, by using both the suction fan for transporting the transfer paper and the ozone exhaust fan, it is possible to detect the abnormality in the transport suction force.

[0027]

According to the above construction, even when the fan is stopped abnormally, it is possible to ensure the prevention of contamination by ozone, and the transfer paper during image formation is discharged from the inside of the machine, so that it remains inside the machine. Post-processing such as transfer paper removal work can be reduced, and the transfer paper is not wasted.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing an abnormality detection device for an ozone exhaust fan according to the present invention.

FIG. 2 is a control block diagram according to the present invention.

FIG. 3 is an operation flowchart of detection control in a CPU.

[Explanation of symbols]

 1 Ozone Exhaust Fan 2 First Duct 3 Second Duct 4 Ozone Filter 20 Reflective Sensor 30 CPU

Claims (2)

[Claims] 1. An abnormality detection device for an ozone exhaust fan of an image forming apparatus, which uses an ozone exhaust fan with an ozone filter to prevent exhaust of ozone generated inside the device to the outside of the device. Anomaly detection means for detecting rotation, and when abnormal rotation is detected by the abnormality detection means, image formation on the transfer sheet during image formation at the time of detection is completed, and the image is formed after being discharged. An abnormality detecting device for an ozone exhaust fan, comprising: a control means for stopping driving of the ozone exhaust fan. 2. The abnormality detecting device for an ozone exhaust fan according to claim 1, wherein the ozone exhaust fan indicates that the fan is abnormally rotating.