JPH0728368A - Cleaning device - Google Patents

Abstract

PURPOSE:To prevent the generation of 'missing' at the time of cleaning and a failure in the cleaning by providing a heater warming up a cleaning blade and taking a cleaning action in 'a state where the temperature of the cleaning blade is over a glass transition point, with the heater. CONSTITUTION:The heater 14 is provided on an L-shaped inside plane on the plate of a holder 12. When the main power source of a device is turned on, first, the heater in a fixing roller 8 is started to generate heat and simultaneously, the heater 14 is started to generate the heat by the control of a CPU 16. Then, the heat of the heater 14 is transmitted to the holder 12 and there, a cleaning blade 9, to warm up it. Time for warming up the cleaning blade 9 is set by the count number of a counter 15. A set count number and the output of the heater 14 are set with the count number, so that the temp. of the cleaning blade 9 is over the glass transition point, at least before the fixing roller 8 is preheated and a copying action can be taken.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photoconductor cleaning device applied to an electrophotographic apparatus such as a copying machine or a laser printer.

[0002]

2. Description of the Related Art FIG. 8 is an explanatory view for explaining an example of the structure of an electrophotographic apparatus and an image recording process. Reference numeral 1 is a belt-shaped photoconductor, and 2 is a photoconductor 1 which is stretched and circulated. Roller 3, charging charger 4, optical writing unit 5, developing unit 5, transfer charger 6, recording paper 7, fixing roller 8, cleaning blade 9, waste toner tank 10, static elimination lamp 11 Show.

First, the charging charger 3 uniformly charges the surface of the photoconductor 1 with respect to the photoconductor 1 that moves in a circulating manner. next,
The optical writing unit 4 exposes the charged photoconductor 1 with laser light to form an electrostatic latent image, and the developing unit 5 attaches toner to the electrostatic latent image to form a visible image. As a result, a toner image is formed on the surface of the photoconductor 1.
This toner image is transferred onto the recording paper 7 by the transfer charger 6, and the fixing roller 8 pressurizes and heats the recording paper 7 to fix the toner image on the recording paper 7, thereby creating a hard copy. .

On the other hand, the toner remaining on the surface of the photoreceptor 1 without being transferred to the recording paper 7 is scraped off by the cleaning blade 9 and collected in the waste toner tank 10. The photoconductor 1 from which the residual toner has been removed is neutralized by the static elimination lamp 11 and initialized.

[0005]

As a material of the cleaning blade, an elastic body such as a rubber material is generally used. When the residual toner on the photoconductor is collected by using the elastic cleaning blade, there is a problem that the cleaning blade is apt to cause defective cleaning due to "chip" or "turning". Further, since the rubber material has a characteristic that it cures at a temperature below a certain temperature (glass transition point), “chips” in particular tend to occur in a low environment.

By the way, in the copying machine, the fixing roller is always at a constant temperature (170 ° C. to 180 ° C.) while the main power is on.
Is kept at. Therefore, if a sufficient time has passed after the main power was turned on, the cleaning blade can be heated to some extent by the air warmed by the fixing roller even in a low environment.

However, for example, when a main power source is turned on in the early morning of winter and a copy is made after waiting for the preheating of the fixing roller, the fixing roller reaches the set temperature, but the cleaning blade is set. The heat is not transmitted to the surroundings enough to warm it. In such a case, the cleaning blade may be chipped.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and to provide a cleaning device which prevents the occurrence of defective cleaning due to the lack of a cleaning blade.

[0009]

In order to achieve the above object, the present invention relates to a photoreceptor for removing the developer remaining on the surface of the photoreceptor after image transfer in an electrophotographic process. In a cleaning device provided with a cleaning blade made of an elastic member that comes into contact with and scrapes off the developer, a heater for warming the cleaning blade is provided.

Further, a temperature sensor for detecting the temperature of the cleaning blade or the vicinity of the cleaning blade is provided, and ON / OFF of the heater is controlled by an output of the temperature sensor.

Further, the present invention is characterized in that a time measuring means for measuring the time after the main power source is turned on is provided and the heater is turned on and off by the output of the time measuring means.

A switch for turning on and off the heater is provided at a position where it can be manually operated.

[0013]

According to the above-mentioned means adopted by the present invention, by heating the cleaning blade with the heater and raising the temperature to the glass transition point or higher before performing the first copy,
It is possible to prevent the occurrence of chipping.

Further, for example, after the fixing roller is sufficiently heated, the cleaning blade is heated by the air warmed by the fixing roller after a certain period of time, so that the heater is always turned on. No need to leave. Therefore, by providing a temperature sensor and a time measuring means and controlling the on / off of the heater, it is possible to keep the heater on until the cleaning blade is warmed by the heat of the fixing roller.

[0015]

Embodiments of the present invention will now be described in detail with reference to the drawings. The same members as those in the conventional technique shown in FIG. 8 are designated by the same reference numerals and detailed description thereof is omitted.

FIG. 1 is a block diagram showing an electrophotographic apparatus provided with a first embodiment of the present invention, and FIG. 2 is a perspective view showing the configuration of a holder and its periphery according to the first embodiment. In FIGS. 1 and 2, reference numeral 12 is a holder for supporting the cleaning blade 9. The holder 12 is composed of an L-shaped plate member in a side view, and support pieces 12a are provided on both sides of an end of one flat plate A in the L shape. The support piece 12a extends in the opposite direction to the other flat plate B of the L-shape, and has a hole 12b in the center thereof.

Further, L on the flat plate A of the holder 12
A cleaning blade 9 is attached to the plane outside the letter shape, and one long side of the cleaning blade 9 extends from the L-shaped bent portion of the holder 12. The holder 12 is rotatably supported by the main body of the apparatus through the hole 12b of the support piece 12a, and the cleaning blade 9 is rotated by the rotation.
Abuts on the photoconductor 1 so that the tip of is opposite to the moving direction of the photoconductor 1.

Reference numeral 13 denotes a spring, and this spring 13
One end is locked to the flat plate B of the holder 12, and the other end is locked to the apparatus main body. When the spring 13 presses the flat plate B, the holder 12 rotates, and the cleaning blade 9 contacts the photoconductor 1.

Reference numeral 14 denotes a heater, which is installed on the flat surface of the flat plate A of the holder 12 inside the L-shape. Further, as shown in FIG. 3, the heater 14 starts to generate heat at the same time when the main power source (not shown) is turned on (S1) (S2), and when the count number set by the counter 15 is counted. (S3), the CPU (Central Processing Unit) 16 is stopped by an instruction (S4).

A rotating member 17 guides the residual toner scraped off by the cleaning blade 9 to the waste toner tank 10.
Reference numeral 18 denotes a flicker that drops the waste toner of the rotating member 17.

When the main power source of the device is turned on, first, the CP
The heater (not shown) in the fixing roller 8 starts to generate heat by the control of U16, and at the same time, the heater 14 starts to generate heat. Then, the heat of the heater 14 is conducted through the holder 12 and transferred to the cleaning blade 9, so that the cleaning blade 9 is warmed.

The time for heating the cleaning blade 9 is
It is determined by the count number of the counter 15 as described above. The count number can be set arbitrarily, but at least before the fixing roller 8 is preheated and the copying operation is possible, the set count number and the heater 14 are set so that the temperature of the cleaning blade 9 exceeds the glass transition point. It is necessary to determine the output of.

With this configuration, the cleaning blade 9 is preheated before the copy operation can be started, so that the copy operation is started and the cleaning blade 9 collects the residual toner. At this time, it is possible to prevent the occurrence of "chip" at the tip.

FIG. 4 is a block diagram showing the essential parts of the second embodiment of the present invention. The same members as those in the first embodiment shown in FIGS. 1 and 2 are designated by the same reference numerals and detailed description thereof is omitted.

In FIG. 4, 19 is a heater and 20 is a temperature sensor. The heater 19 is installed near the cleaning blade 9 and heats the cleaning blade 9 by heating the air around the cleaning blade 9. The temperature sensor 20 is arranged on the flat plate A of the holder 12 and further detects the temperature of the holder 12.

FIG. 5 is a block diagram showing the control system of the second embodiment shown in FIG. As shown in FIG. 5, each unit in the electrophotographic apparatus is controlled by the CPU 16.
In particular, the heater 19 is turned on / off according to the output result of the temperature sensor 20, and the fixing heater 8a for heating the fixing roller 8 is turned on / off according to the output result of the thermistor 8b which detects the surface temperature of the fixing roller 8.

FIG. 6 is a flow chart for explaining the operation of warming the cleaning blade 9 in the second embodiment. Next, the operation of the second embodiment will be described with reference to FIGS.

When the main power source is turned on, the fixing roller 8 (see FIG.
(Refer to FIG. 3), and at the same time, the temperature sensor 20 detects the temperature of the holder 12 at the present time, and it is determined whether or not the temperature exceeds the set temperature (S10). If the set temperature is exceeded, the temperature of the holder 12 is continuously monitored thereafter. If it is lower than the set temperature, turn on the heater 19 and
Holder until the cleaning blade 9 exceeds the set temperature
Continue heating 12 (S12). Then, when the temperature exceeds the set temperature, the heater 19 is turned off (S13), and thereafter, the temperature of the holder 12 is continuously monitored.

With this configuration, the temperature of the cleaning blade 9 can be maintained in a state of exceeding the set temperature, and the occurrence of "chip" can be prevented as in the first embodiment. Further, when the cleaning blade 9 is located near the fixing roller 8, the cleaning blade 9 is warmed by the heat of the fixing roller 8 when a sufficient time has passed after the main power was turned on. Therefore, in the second embodiment, the fixing roller 8
Since the heater 19 can be turned on only for the time until the cleaning blade 9 is warmed by the heat of 1, the power consumption by the heater 19 can be reduced.

Although the embodiments have been described above, the embodiments of the present invention are not limited to the configurations of the first and second embodiments described above.

For example, in the second embodiment shown in FIG. 4, the temperature sensor 20 is installed in the holder 12, whereas the temperature sensor 21 is arranged near the cleaning blade 9 as shown in FIG. Good.

Further, a switch for turning on / off the heater for heating the cleaning blade 9 is provided so that a user or a service person can manually turn on / off the heater so that the heater can be turned on only when necessary. May be.

[0033]

The present invention constructed as described above has the following effects.

According to the first aspect of the present invention, the heater for heating the cleaning blade is provided, and the heater can perform the cleaning operation in a state where the temperature of the cleaning blade exceeds the glass transition point. Can be prevented and defective cleaning can be prevented.

According to the second aspect of the present invention, the temperature of the cleaning blade or the temperature in the vicinity of the cleaning blade is detected by the temperature sensor, and the heater is turned on / off based on the detection result. Since it can be maintained in a state of exceeding, it is possible to prevent the occurrence of "chip" during cleaning.

According to the third aspect of the present invention, the heater is turned on when the main power source is turned on, and the heater is automatically turned off after a lapse of a predetermined time, thereby suppressing power consumption by the heater. be able to.

According to the structure of claim 4, the heater is turned on,
Since the turning off can be operated by a user or a service person, by turning off the heater when unnecessary, it is possible to avoid wasting electricity.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an electrophotographic apparatus including a first embodiment of the present invention.

FIG. 2 is a perspective view showing a holder and its peripheral members according to the first embodiment.

FIG. 3 is a flowchart showing a flow of an operation of warming a cleaning blade in the first embodiment.

FIG. 4 is a configuration diagram showing a main part of a second embodiment of the present invention.

FIG. 5 is a block diagram showing a control system of an electrophotographic apparatus including the configuration of the second embodiment.

FIG. 6 is a flowchart showing a flow of an operation of warming a cleaning blade in the second embodiment.

FIG. 7 is a configuration diagram showing a main part of another embodiment of the present invention.

FIG. 8 is a configuration diagram showing an example of a configuration of a conventional electrophotographic apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Photosensitive member, 8 ... Fixing roller, 9 ... Cleaning blade, 12 ... Holder, 14, 19 ... Heater, 15 ... Counter, 16 ... CPU, 20, 21 ... Temperature sensor.

Claims (4)

[Claims] 1. A cleaning blade comprising an elastic member for scraping off the developer by contacting with the photoconductor in order to remove the developer remaining on the surface of the photoconductor after image transfer in the electrophotographic process. A cleaning device comprising a heater for heating the cleaning blade. 2. The cleaning device according to claim 1, further comprising a temperature sensor for detecting the temperature of the cleaning blade or the vicinity of the cleaning blade, and turning on / off of the heater is controlled by an output of the temperature sensor. 3. The cleaning device according to claim 1, further comprising a time measuring means for measuring a time after the main power source is turned on, and turning on / off of the heater is controlled by an output of the time measuring means. 4. The cleaning device according to claim 1, wherein a switch for turning on and off the heater is provided at a position where it can be manually operated.