JPS63127279A - Blade cleaning device - Google Patents

Abstract

PURPOSE:To keep the picture quality of copies in a satisfactory state at the time of continuous copying by detecting the revolution of a photosensitive drum and rocking a cleaning blade at every prescribed revolution of the photosensitive drum. CONSTITUTION:An input part 21 to which the number of copies is inputted, an input part 22 to which the revolution of the photosensitive drum is inputted from a detector, and a blade rocking timing setter 23 are connected as input devices to a controller 20. The controller 20 outputs ad signal 24 applies to a solenoid, a copying operation interrupting signal 25, etc., to separate the blade from the photosensitive drum and outputs information to a microcomputer 26 constituting the controller of a printer to control image formation, form feeding, etc. The copying operation is interrupted and the cleaning blade is rocked to remove a stuck toner or the like at every time of prescribed revolution of the photosensitive drum during continuous copying, thus keeping the copy picture quality in the satisfactory state.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a cleaning device using a cleaning blade for cleaning a photoreceptor drum. The blade is configured to be separated from the photosensitive drum every predetermined rotation of the drum, and the blade is configured to be able to shake off adhered toner, paper dust, etc. when the blade is rapidly swung. Regarding the ¥A placement.

(Prior Art) In devices such as electronic copying machines, an image carrier provided on the surface of a photoreceptor drum or the like is uniformly charged with a charging rod, and the surface is illuminated with light emitted from an original. An electrostatic latent image is formed, and then toner is supplied from a developing device to the electrostatic latent image to visualize it as a toner image.

Furthermore, in devices such as electrophotographic printers, the method of forming an electrostatic latent image is different from that of the above-mentioned electronic copying machine, and instead of reading the original image with an image reading device, it is input into a storage device. The difference is that a light-emitting element such as a laser is turned on based on the information provided, and the light is irradiated onto the photoreceptor drum to form an electrostatic latent image, but the other configurations are the same as in the case of an electronic copying machine. considered to be almost identical. Therefore, the cleaning device described below will be explained as being common to the above-described devices.

The toner image formed on the surface of the photoreceptor drum as described above is then moved to an image transfer section, where it is transferred onto paper by a transfer member such as a transfer corotron, and the toner image is transferred to a sheet of paper by a transfer member such as a transfer corotron. The paper onto which the image has been transferred is introduced into a fixing device, where it is heated and pressurized to complete the copy.

However, in the image transfer process described above, not all of the toner image formed on the photoreceptor drum is transferred to the paper, and several percent or more remains attached to the photoreceptor drum. remain.

Therefore, in devices such as electronic copying machines that have been used conventionally, a cleaning action is performed by a cleaning device between the above-mentioned image transfer process and the next charging process by a charger, which prevents toner from adhering to the surface. The raw material is supplied to the next process in a state where it is not completely removed.

Conventionally, cleaning devices for photoreceptor drums include:
Devices using rotating brushes, devices using cleaning blades, etc. are known. Among these devices, devices using rotating brushes such as fur brushes have the advantage of being able to perform cleaning operations without damaging the surface of the photoreceptor drum. In addition to the relatively complicated mechanism, such as the need to use a suction fan, there are many problems in terms of cost, space, power consumption, noise, etc.

On the other hand, a cleaning device using a cleaning blade has a simple mechanism and requires only one
It is said that it is possible to scrape off toner and paper dust and clean the image forming surface of the photoreceptor drum by simply pressing the tip of the blade against the surface of the photoreceptor drum using a plate-shaped blade. There is.

(Problems to be Solved by the Invention) However, in the cleaning device using the conventional cleaning blade as described above, the tip of the blade is constantly pressed against the surface of the photoreceptor drum. It has the disadvantage that the tip part is particularly prone to wear.

In addition, if the material of the blade is not uniform, or if the pressure applied to the surface of the photoreceptor drum is not balanced, the cleaning action will be uneven, resulting in sushi-like formations on the surface of the photoreceptor drum after cleaning. Problems such as toner remaining and staining the next copy are likely to occur.

In addition to this, if the cleaning blade is installed correctly, its cleaning action will be performed reliably;
In addition to toner adhering to the surface of the photoreceptor drum, the blade scrapes off a mixture of paper powder and dust generated from the electronic copying machine. These scraped items may get stuck between the cleaning agent and the cleaning agent, resulting in defects such as incomplete cleaning.

On the other hand, in the above-mentioned cleaning apparatus, an apparatus is sometimes used which is equipped with a mechanism for separating the cleaning blade from the photosensitive drum when the electronic copying machine is stopped.

However, in a device equipped with such a blade swinging mechanism, the swinging mechanism is not activated during copying, so even if a large number of copies are to be made in succession, Even if the blade becomes dirty, it cannot be cleaned, resulting in the formation of smudge-like stains, resulting in defects such as gradually blurring of copies.

To deal with this, we constantly monitor the copy status and
When an operator finds dirt, he or she stops the electronic copying machine and cleans the blade, but this is a very inefficient method and greatly reduces the efficiency of copying. This poses a very serious problem, such as lowering the temperature.

<Object of the Invention> The present invention solves the above-mentioned drawbacks of conventionally used cleaning devices. It is an object of the present invention to provide an apparatus that can set a cycle, temporarily interrupt the copying operation, automatically clean the blade, and then continue the copying operation.

(Means and effects for solving the problem) The blade cleaning device of the present invention includes a blade swinging means configured to swing the cleaning blade and release the pressure of the blade against the photosensitive drum, A detection means for detecting the number of rotations of the photosensitive drum is provided, and at every predetermined number of rotations of the photoreceptor drum, the copying operation is interrupted and the blade is oscillated to shake off toner etc. adhering to the blade. It is configured so that it can be done.

Therefore, in the apparatus of the present invention, when a large number of copies are made continuously from the same original, a cycle for cleaning is automatically set in the middle of the copying, and the copying operation is interrupted and the blade is removed. By swinging the blade, toner and the like attached to the blade can be removed.

With the above-described configuration, the blade cleaning device of the present invention can prevent the image quality of copies from deteriorating as the number of copies increases, unlike in the case of conventional devices.

(Execution W4> The configuration of the blade cleaning device of the present invention will be described according to the illustrated embodiment.

As shown in FIG. 1, around the photosensitive drum 1,
As in the case of conventionally used electronic copying machines, a charge corotron 2, a developing device 4, a transfer corotron 5, a transfer corotron 6, a peeling corotron 7, etc. are provided.

Further, the cleaning device 10 provided subsequent to the paper peeling section of the photoreceptor drum 1 includes a cleaning blade 15 that comes into contact with the surface of the photoreceptor drum 1, a blade holder 11 for holding the blade, and a blade holder 1.
The blade holder is comprised of a fulcrum 12 constituting a fulcrum for swinging the blade holder, a solenoid 13 and a spring 14 for swinging the blade holder.

When this photosensitive drum 1 is used in an electrophotographic printer, a charge corotron 2 and a developing device 4 are used.
A light irradiation section 3 provided between the printer and the printer irradiates the printing document with light obtained by a laser beam generator.

In an electrophotographic printer using this photoreceptor drum, when printing is performed, the surface of the image carrier of the photoreceptor drum 1 is first uniformly charged by a charge corotron 2. The layer is irradiated with laser light generated from the light irradiation section 3, thereby forming an electrostatic latent image on the surface of the photoreceptor drum. Thereafter, toner is supplied from the developing bag M4 to visualize the electrostatic latent image as a toner image.

For the toner image thus obtained, the pre-transfer corotron 5 weakens the adhesion of the toner to the photoreceptor drum, and the transfer corotron 6 transfers the image to the paper conveyed via the paper conveyance path 8. Perform transcription.

During image transfer, electric charges are supplied to the paper that is in close contact with the surface of the photoreceptor drum 1.
An alternating current discharge is generated from the back side by a peeling corotron 7 to remove static electricity and peel the paper.

If this peeling operation cannot be performed sufficiently by the peeling corotron alone, a peeling claw device or the like is provided in the paper peeling section to forcibly peel off the paper to which the toner image has been transferred, and the fixing device By applying heat and pressure to the toner that forms the toner image, it is fixed to the paper and completed as a copy.

Further, the cleaning device 10 provided subsequent to the image transfer section of the photosensitive drum has a solenoid 13 installed at the end of the blade holder 11 that holds the cleaning blade 15.
and the spring 14 are provided so as to face each other,
During normal printer operation, the cleaning blade 15 is pressed against the surface of the photoreceptor drum 1 with a predetermined pressure.
The rotation of the photosensitive drum performs a cleaning action by scraping off toner and the like adhering to its surface.

That is, in the blade cleaning device of the present invention, when performing a printing operation using a normal printer, the power supply to the solenoid 13 is turned off, and the cleaning grade 15 is pressed against the surface of the photoreceptor drum 1 by the force of the spring 14. Therefore, the state shown in FIG. 2(a) is maintained.

On the other hand, when one cycle of printing operation by the printer is completed, the solenoid 13 is turned on by a signal such as a stop signal for the rotation of the photoreceptor drum, and the solenoid 13 acts against the force of the spring 14. Since the blade holder 11 is rotated in the opposite direction via the fulcrum 12, the tip of the blade 15 is moved +mts away from the photoreceptor drum 1, as shown in FIG. 2(b).

In addition, since the blade swinging device of the present invention rapidly swings the blade holder 11 using the solenoid 13, the impact generated at that time causes the toner etc. adhering to the blade to be brushed off. Paper powder and the like caught between the surface of the photosensitive drum and the like fall at the same time, and are discharged to the toner recovery device by a conveying device or the like provided at the bottom of the housing of the cleaning device.

In addition to the normal printing operation of an electrophotographic printer, an electrophotographic printer using the cleaning device of the present invention also uses the cleaning device when printing multiple copies of the same image in succession. It is configured to be activated at predetermined intervals.

Regarding the control in this electrophotographic printer, the third
This will be explained using figures. As shown in FIG. 3, in the third aspect of the present invention, an input section 21 for inputting the number of copies
and an input unit 22 from a photoconductor drum rotation speed detection device,
A blade swing timing setting device 23 is connected as an input device to the control device 20.

In addition, the control device 20 outputs a solenoid application signal output unit 24, a copy operation interruption signal 25, etc., and performs an operation to separate the blade from the photoreceptor drum.
The information is outputted to a microcomputer 26 constituting a control device of the printer, and controls operations such as image formation on the photosensitive drum and sheet feeding operation.

Therefore, when copying the same image plane continuously using the apparatus of the present invention, the photosensitive drum rotation speed detection device 22
The number of copies is detected based on the signal from the
The signal from the blade swing timing setting device is compared with the number of copies, and when the number of copies reaches a predetermined number,
The control device 20 outputs a copy operation interruption signal to the microcomputer 26 to interrupt the printer operation, turns on the solenoid 13 in response to the solenoid application signal, and separates the blade from the photoreceptor drum 1.

The control operation in this case will be further explained with reference to the timing chart of FIG. 4. When copy making work is performed continuously, the control device is input.

Then, when the number of copies reaches a predetermined number set in advance by the blade swing timing setting device,
A dead cycle is set by the output from the controller. When the cycle is set, a copy operation interruption signal is output, and a blade swing signal is output.
The solenoid is turned on at a predetermined timing, and the
), the blade is separated from the photoreceptor drum.

After the solenoid remains on for a certain period of time, the solenoid is turned off again and the blade is brought into contact with the photoreceptor drum, as shown in FIG. An activation signal of the detection device is output, which causes a toner image to be formed on the surface of the photoreceptor drum.
The operation of measuring the density of the image is performed.

Note that while these operations are being performed, the main motor that rotates the photoreceptor drum continues to drive, so the photoreceptor drum is not stopped and the developing roller of the developing device remains in operation. be.

However, during the above-described control operation, the irradiation of image information onto the photoreceptor drum is interrupted, so no toner image is formed on the photoreceptor drum except when performing image density detection. Furthermore, when performing image density detection, the blade is in contact with the photosensitive drum, so the cleaning device is in a normally operating state.

By performing the above-mentioned dead cycle setting operation at intervals set by the blade swing timing setting device, the blade swings and toner etc. are removed without stopping the operation of the electrophotographic printer. Remove any deposits.

Note that the timing of the swinging of the blade in the blade cleaning device of the present invention depends on the quality of the paper used in the printer and the surface of the photoreceptor drum, since the main component of what is scraped off by the blade is often paper dust. An appropriate interval can be set depending on the state of the blade, the material of the blade, etc., and the control operation can be performed.

Furthermore, depending on the nature of the object to be scraped, it is of course possible to repeat the blade tract operation not only once but multiple times during one cycle.

Further, in the above-described embodiments of the present invention, the case of an electrophotographic printer was explained, but the cleaning device of the present invention is naturally applicable to devices such as an electronic copying machine, and in particular, the cleaning device of the present invention can be applied to devices such as an electronic copying machine. When copying the same document, the photosensitive drum can be cleaned effectively.

(Effects of the Invention) Since the blade cleaning device of the present invention has the above-described configuration, when printing a large number of sheets in succession, it is possible to remove paper dust etc. that adheres to the blade during copying. Foreign matter can be removed and the image quality of copies can be maintained in good condition.

Furthermore, since the cleaning device of the present invention interrupts the copying operation at a set timing even in the middle of the printing operation, the operator does not need to monitor the image quality of the copies, and is freed from unnecessary work. will be done.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the configuration of the cleaning device of the present invention and a photosensitive drum, FIG. 2(a) is an explanatory diagram of the cleaning state, and FIG. FIG. 3 is an explanatory diagram showing the control device of the present invention, and FIG. 4 is a timing chart showing control operations by the control device. Reference numerals in the figure 1...Photosensitive drum, 2...Charge corotron, 3...Light irradiation section, 4...
Developing device, 5...Bri transfer corotron', 6.
...Transfer corotron, 7...Peeling corotron, 10...Cleaning device, 11...
...Blade holder, 12...Fulcrum, 13
... Solenoid, 14 ... Spring, 15 ... Cleaning blade, 20 ...
...Control! ll device. (1 other person) Figure 1 Figure 2 ((:L) (b) Figure 3 Figure 4 Development -

Claims (1)

[Scope of Claims] A toner image is formed on the surface of a photoreceptor drum of an electrophotographic printer or an electronic copying machine, and the toner image is transferred to paper, and the remaining toner is pressed against the surface of the photoreceptor drum. A device equipped with a cleaning blade for cleaning the photoreceptor drum, comprising: a swinging means for swinging the cleaning blade at a constant rotation speed of the photoreceptor drum to release the blade from contact with the photoreceptor drum; a detection means for detecting the number of rotations, and the blade is oscillated every predetermined number of rotations of the photosensitive drum, and dirt such as toner attached to the blade is removed by the oscillation. A blade cleaning device characterized by: