JPH02296276A - Electrophotographic device - Google Patents

Abstract

PURPOSE:To improve cleaning ability based on a printed result without interrupting the operation by contacting / separating from an image carrier at an appropriate timing a blade of a mechanical method cleaning means provided along with a magnetic cleaning means with manual procedure. CONSTITUTION:A magnetic method cleaning means 10 provided integrally with a developing device 4, and a mechanical cleaning means 20 formed including a blade 22 are provided together. Then while the image carrier 1 is cleaned by the magnetic method cleaning means 10, if improvement of the cleaning ability is required from the printing result, the mechanical cleaning means 10 is operated manually to contact / separate from the image carrier the blade 22 at an appropriate timing and supplementary cleaning is carried out. Thus, the cleaning ability can be adjusted based on the printing result without interrupting the operation of the device.

Description

[Detailed description of the invention] [Industrial application fields] The present invention relates to an electrophotographic apparatus.

[Prior Art] FIG. 4 shows the general structure of a conventional electrophotographic apparatus, in which reference numeral 1 denotes a drum-shaped image carrier that is rotatably provided. Around the image carrier 1, there is a charger 2 that uniformly charges the surface of the image carrier 1, and a laser beam is irradiated onto the charged surface of the image carrier 1 based on print data etc. to generate an electrostatic latent. An exposure section 3 that forms an image, a developing device 4 that attaches toner to the image carrier 1 on which the electrostatic latent image is formed and develops it, and transfers the toner image formed on the image carrier 1 onto a sheet of paper 9. A transfer device 5 for removing electricity from the image carrier 1 and a static eliminator 6 for removing electricity from the charged image carrier 1 after the transfer are sequentially arranged.

By the way, if toner, paper powder, etc. remain on or adhere to the image carrier 1 after the transfer, a portion of the printing surface of the paper to be printed next often becomes dark, causing printing defects. For this reason, the electrophotographic apparatus is provided with a cleaning means for cleaning the image carrier 1.

Conventionally, the cleaning means is provided integrally with the developing device 4, performs development in cooperation with the developing device 4, and collects the toner 12 remaining on the image carrier 1 into the developing device 4 by magnetic action. A magnetic cleaning means 10 configured to clean the image carrier 1 is known.

Further, as a cleaning means, as shown in Fig. 4,
A mechanical cleaning means 20 is also known in which the blade 22 is brought into contact with the surface of the image carrier 1 to scrape off residual toner from the surface and store the residual toner in a waste toner storage section 23.

Since this mechanical cleaning means 20 directly scrapes off the residual toner with the blade 22, it may be possible to perform good cleaning over a long period of time. The disadvantage is that the surface of the carrier 1 is easily damaged and it is difficult to maintain good printing quality.

On the other hand, although the control of the magnetic cleaning means 10 tends to be more complicated than that of the mechanical cleaning means 20, since the residual toner can be collected and reused without contacting the image carrier 1, it is used in recent electrophotographic apparatuses. In many cases, a magnetic cleaning means 10 is selectively used as a cleaning means.

[Problems to be Solved by the Invention] Here, if the residual toner is firmly attached to the image carrier 1, even if the image carrier 1 is cleaned by the magnetic cleaning means 10, the cleaning performance may be reduced. It is not possible to remove the insufficient residual toner, which may cause printing defects such as partial darkening of the printed surface of the paper 9. In particular, the magnetic cleaning means 1
0 deteriorates with use and its cleaning ability decreases, the above-mentioned printing defects are likely to occur.

However, due to its structure, the magnetic cleaning means 10 cannot be adjusted while the electrophotographic apparatus continues to operate. Therefore, if insufficient cleaning is found from the printing results as described above, it is necessary to immediately stop the operation of the device and adjust the magnetic cleaning means 10 to increase the cleaning ability, which reduces printing efficiency. It will drop.

An object of the present invention is to provide an electrophotographic method that can adjust the cleaning ability of a cleaning means based on printing results without interrupting operation, and that can prevent deterioration of printing quality and printing efficiency over a long period of time. The goal is to provide equipment.

[Means for Solving the Problems] The present invention cleans the image bearing member using a magnetic cleaning means, and when it is found from the printing result that cleaning is insufficient, the mechanical cleaning means is operated manually. This structure is designed to increase the cleaning ability.

That is, the present invention includes a magnetic cleaning means provided integrally with the developing device and a mechanical cleaning means formed including a blade, and the mechanical cleaning means is manually operated to remove the blade from the image. It is characterized by being configured so that it can come into contact with and separate from the carrier at appropriate timing.

[Function] In the present invention, in addition to cleaning the image bearing member using the magnetic cleaning means, when it is desired to improve the cleaning ability based on the printing result, the mechanical cleaning means is manually operated to move the blade to the image bearing member at an appropriate timing. It acts to perform auxiliary cleaning by contacting and separating the parts.

[Example code] An embodiment of the present invention will be described based on the drawings.

In this embodiment, as shown in FIG. 1, an image carrier 1, a charger 2,
, an exposure section 3, a developing device 4, a transfer device 5, a static eliminator 6, etc., and a magnetic cleaning device 1 provided integrally with the developing device 4 as a cleaning device.
0.

Components that are the same as those shown in FIGS. 3 and 4 are designated by the same reference numerals, and their explanations will be omitted or simplified.

Here, the magnetic cleaning means 10 is formed to cooperate with the developing device 4 to alternately perform a developing action and a cleaning action at predetermined time intervals, as shown in FIG. Here, the predetermined time t is selected to correspond to the time required for the image carrier 1 to rotate once.

On the other hand, the i-line cleaning means 20 manually moves the blade 22 to the image carrier 1 as appropriate so that the cleaning ability of the entire electrophotographic apparatus can be improved based on the printing results without interrupting the operation of the electrophotographic apparatus. It is configured so that they can be brought into contact and separated at the appropriate timing. Here, manual operation means operating the blade according to the operator's will without being based on a preset program.

In this embodiment, the mechanical cleaning means 20 includes:
It is configured to include a blade 22, a lever 24, etc., and is formed so that the blade 22 can come into contact with and separate from the surface of the image carrier 1.

More specifically, the blade 22 is provided at the lower end of a rotatably provided lever 24.
It is formed so that it can come into contact with and separate from the image carrier 1 by rotating 4.

Further, the blade 22 is normally separated from the image carrier 1 by the cooperation of a lever 24 and a spring 27, and is rotated counterclockwise against the elasticity of the lever 24 or the spring 27 to form an image. It is formed so as to be in contact with the carrier 1.

Further, the lever 24 has its upper portion protruding upward from the opening 7a of the cover 7 covering the image carrier 1 and the like so that it can be easily operated from the outside. Further, a scale (not shown) for measuring the amount of rotation of the lever 24 is provided near the opening 7a of the cover 7. Therefore, by grasping the upper part of the lever 24 and rotating it appropriately, the blade 22
can be brought into contact with and separated from the image carrier 1 at appropriate timings. At this time, the contact pressure of the blade 22 can be easily changed by adjusting the amount of rotation of the blade 22 using the scale as a guide.

Furthermore, the mechanical cleaning means 20 is provided with a solenoid 25 that rotationally drives a lever 24 so that the blade 22 can be manually operated from a location conveniently accessible from the process means of the electrophotographic apparatus. The solenoid 25 is a key (for example, #-31 not shown in FIG. 1) provided on the operation panel.
) is activated via the automatic control means 30 and interface 26, which will be described later. In this embodiment, since the blade 22 is not in constant contact with the image carrier 1 and does not damage it, the magnetic cleaning ability is 1.
The contact pressure of the blade 22 is set to be strong so that even residual toner that cannot be removed by zero can be easily rubbed off.

Further, the electrophotographic apparatus includes a blade 22 so that the mechanical cleaning means 20 can be operated at appropriate time intervals to supplement the cleaning ability of the magnetic cleaning means 10.
An automatic control means 30 is also provided for automatically and intermittently bringing the image carrier into contact with and separating from the surface of the image carrier 1.

Here, in this embodiment, the automatic control means 30 is a part of an automatic control device (CPU, RO,
(M, RAM, operation panel, timer, etc.).

The automatic control means 30 has an operation stop function that repeatedly brings the blade 22 into contact with and away from the image carrier 1 at predetermined time intervals. That is, the automatic control means 30 drives the solenoid 25 via the interface 26 to
As shown in Figure (c), the blade 22 carries the image for each predetermined time (operating time T0°T1.T2.Ts...) at predetermined time intervals (rest time t.1t1.jz, j3..). ROM contains a program whose content is to contact the body 1.
Built-in.

Here, the above-mentioned rest time and operation time are selected so that residual toner that cannot be completely collected by the magnetic cleaning means 10 can be scraped off without damaging the surface of the image carrier 1 by the blade 22. .

For example, the pause time t. , t+, t2+ t3, . . . can be kept constant as shown in FIG. 2(c) and can be selected as the operating time required to print 600 sheets of paper. Moreover, each operation time To, T1. T2, T3...
can be selected as a constant operating time required to print two sheets of paper.

In addition, as the operating time becomes longer, the amount of residual toner adhering to the image carrier 1 increases, so as shown in FIG. (e.g. equivalent to printing 600 sheets of paper) and operating time T
. , T+, T2. T3... becomes gradually longer (
For example, T. is equivalent to printing two sheets of paper, and T1. T2. Ts
...or 3.4.5 sheets of paper...equivalent to printing) may be selected.

Furthermore, as shown in FIG. 2(a), the operating time (T, ,T,
, T2. T, -) are kept constant (for example, equivalent to printing 2 sheets of paper), and the pause time (to, t,, t2, t3...) is gradually shortened (for example, 70 is equivalent to printing 600 sheets of paper, 1..12.13... may be selected so that they are equivalent to printing 400 sheets, 300 sheets, 200 sheets, etc.).

The numerical values selected as the rest time and operation time are stored in the RAM of the automatic control means 30 via the operation panel. Note that these numerical values can be changed via the operation panel.

Next, the effect will be explained.

When a start command is issued from the operation panel, the automatic control device controls the rotation of the image carrier 1 and turns on the charger 2.
, the exposure unit 3, the developing device 4, etc. are driven and controlled according to a predetermined procedure to develop a toner image on the image carrier 1, and the toner image is transferred onto the paper 9 fed by the transfer device 5, and then transferred. After that, the static eliminator 6 is driven to eliminate the residual charge on the image carrier 1.

When the development cycle is thus completed, the automatic control device stops driving the charger 1, the exposure section 3, the development device 4, the transfer device 5, etc., and performs magnetic cleaning while controlling the rotation of the image carrier 1. The image carrier 1 is cleaned by means 10 for a predetermined time t, and the magnetic powder toner 12 remaining on the image carrier 1 is collected into the developing device 4 and the image carrier 1 is cleaned.

In this way, printing is performed continuously while alternating the development cycle and the cleaning cycle.

By the way, the automatic control means 30 determines that the operating time is the rest time t.
. (That is, equivalent to printing 600 sheets of paper), the solenoid 25 is driven via the interface 26 to move the blade 22 to the image carrier 1 for an operating time T. (that is, the contact is made by the amount equivalent to printing two sheets of paper). As a result, the image carrier 1 is auxiliary cleaned by the blade 22, and residual l, toner, etc. that could not be removed by the magnetic cleaning means 10 are rubbed off.

Thereafter, each time the operating time reaches the rest time t+, t2, t3, etc., the automatic control means 30 drives the solenoid 25 to bring the blade 22 into contact with the image carrier 1 for the operating time T, T2, T3,... to remove any uncollected residual toner.

By the way, if cleaning is found to be insufficient from the printing results during operation of the apparatus, if the automatic control means 30 waits for auxiliary cleaning by the blade 22 based on the auxiliary cleaning program, a large number of printing defects will occur. There are many.

Therefore, in such a case, it is necessary to forcibly bring the blade 22 into contact with and separate from the image carrier 1 by manual operation to improve the cleaning ability of the entire apparatus.

To do this, the operator grasps the upper part of the lever 24 and rotates the lever 24 to bring the blade 22 into contact with and away from the image carrier 1, thereby performing auxiliary cleaning, without interrupting the operation. This makes it possible to improve the cleaning ability of the entire apparatus and eliminate printing defects without interrupting operation.

In this case, the blade 22 may be manually operated from the operation panel. That is, when a manual command signal is input via the operation panel, the automatic control means 30 drives the solenoid 25 via the interface 25 with priority over execution of the auxiliary cleaning program, and performs the operation as shown in FIG. 2(a).
), (b), and (C), as shown by the two-dot chain line, the blade 22
is brought into contact with the image carrier 1 for a predetermined time Tr for cleaning.

Therefore, a magnetic cleaning means 10 provided integrally with the developing device 4 and a mechanical cleaning means 20 formed including a blade 22 are provided together, and the mechanical cleaning means 20 can be manually operated to clean the blade 22. Since it is configured to be able to come into contact with and separate from the image carrier 1 at appropriate timings, if insufficient cleaning is found from the printing results, the mechanical cleaning means 20 is operated manually to clean the magnetic cleaning means 10. ability can be supplemented. Therefore, it is possible to improve the cleaning ability of the cleaning means based on the printing results without interrupting the operation, and it is possible to prevent deterioration of printing quality and printing efficiency over a long period of time.

In addition, the mechanical cleaning means 10 is configured so that the blade 22 is brought into contact with the image carrier 1 by grasping and rotating the lever 24 by hand. The contact pressure can be changed as appropriate.

This makes it possible to appropriately adjust the cleaning ability of the entire apparatus depending on the printing results. In this case, cover 7
Since a mark for measuring the amount of rotation of the lever 24 is provided near the opening 7a, the cleaning ability can be easily adjusted using the mark.

In addition, the mechanical cleaning means 10 is configured to drive the solenoid 25 by pressing a key 31 on the operation panel to bring the blade 22 into contact with and away from the image carrier 1. The blade 22 can be manually operated from a remote location, increasing the degree of freedom in layout.

Furthermore, since the blade 22 is configured to come into contact with and separate from the image carrier 1 using the lever 24, auxiliary cleaning can be performed reliably with a simple configuration, and from this point of view, stable cleaning can be achieved over a long period of time. can.

Further, by manually bringing the blade 22 into contact with the image carrier 1, it is possible to scrape off paper dust and the like from the large-diameter paper 9 and prevent it from entering the developing device 4. Therefore, also from this point of view, development can be performed smoothly and deterioration in print quality can be prevented.

Further, since most of the residual toner is collected and reused by the magnetic cleaning means, there is no need to enlarge the waste toner storage section 23 of the mechanical cleaning means 20, and miniaturization of the electrophotographic apparatus is not hindered.

In the above embodiment, the lever 24 of the mechanical cleaning means 20 is configured such that its upper part protrudes outside the cover 7, or the blade 22 is
The structure may be such that the image carrier 1 is not damaged due to careless operation. That is, as shown in FIG.
4 is housed in the cover 7 as a whole, and when manually operating the blade 22, the lever 24 is rotated by opening a mob provided in the opening/closing part 7a of the cover 7 so as to be openable and closable. It's okay.

In addition, although the key 31 provided on the operation panel was used as a means for inputting a manual command signal from the key 31 on the operation panel to the automatic control means 30, a switch for manual operation (not shown) is provided near the lever 24, etc. A manual command signal may be input to the automatic control means 30 by pressing the switch. This allows you to easily operate the switch while checking the print result.
If it is determined from the print result that cleaning is insufficient, the switch 31 can be pressed immediately to operate the mechanical cleaning means 20. At this time, the manual command signal may be input only while the switch is being pressed by hand. Alternatively, the switch may be configured to be mechanically locked when pressed by hand so that the manual command signal continues to be input.

[Effects of the Invention] According to the present invention, a magnetic cleaning means provided integrally with the developing device and a mechanical cleaning means formed including a blade are provided together, and the mechanical cleaning means can be manually operated. Since the blade is configured to be able to come into contact with and separate from the image carrier at appropriate timing, the cleaning ability of the cleaning means can be increased based on the printing results without interrupting operation, and the printing quality can be improved over a long period of time. - It is possible to prevent a decrease in printing efficiency.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing the main part of one embodiment of the present invention, FIG. 2 is a schematic diagram showing the main part of another embodiment of the invention, and FIG. 3 is a timing chart for explaining the operation. It is. 4 and 5 are schematic diagrams showing the main parts of a conventional electrophotographic apparatus, in which FIG. 4 has a magnetic cleaning means as a cleaning means, and FIG. 5 has a mechanical cleaning means as a cleaning means. This is the case. DESCRIPTION OF SYMBOLS 1... Image carrier, 4... Developing device, 10... Magnetic cleaning means, 20... Mechanical cleaning means, 22... Blade.

Claims (1)

[Claims] (1) A magnetic cleaning means provided integrally with the developing device and a mechanical cleaning means formed including a blade are provided, and the mechanical cleaning means is manually operated to move the blade to the image carrier. An electrophotographic device characterized in that it is configured so that it can be brought into contact and separated at appropriate timings.