JPH0233260Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a technique for improving a cleaning device installed in an electrostatographic copying machine or the like.

[Prior Art] Such a cleaning device rotates about a rotation axis parallel to the rotational axis of the photoconductor at an upper portion of the photoconductor and upstream in the rotational direction of the photoconductor with respect to a magnetic brush developing device. An elastic blade for cleaning is freely provided, and the elastic blade is placed in a first position in which the tip of the blade contacts the surface of the photoconductor to block residual toner on the surface of the photoconductor, and in a first position in which the blocked residual toner is removed from the photoconductor. A structure has been proposed in which the blade tip can be freely switched to a second position in which the tip of the blade is separated from the surface of the photoreceptor so that it is collected by the magnetic brush of the developing device as the blade rotates.

According to the cleaning device described above, by switching the elastic blade to the first attitude while the photoreceptor is rotating, residual toner on the surface of the photoreceptor is removed and blocked, and while the photoreceptor is rotating, the residual toner is removed and blocked. By switching the elastic blade to the second position, the blocked toner is collected by the magnetic brush of the developing device while being carried on the photoreceptor, and the toner collected by the cleaning device is transferred to the screw and pipe. Compared to recycling means in which the developing device is returned to the developing device, the components and the drive device can be simplified.

[Problem that the invention attempts to solve] However, in the conventional cleaning device,
Since no consideration was given to the wind generated along the surface of the photoreceptor as the photoreceptor rotates, the wind collides with the elastic blade and becomes turbulent. When the toner blocked by the elastic blade scatters, or when the elastic blade is switched to the second position, the previously turbulent wind flows between the tip of the elastic blade and the surface of the photoreceptor. As a result, the toner carried on the surface of the photoreceptor and to be collected by the magnetic brush is blown away, and the scattered toner stains the transfer paper or adheres to other devices, causing malfunctions. There were many cases where it caused negative effects such as causing problems.

The present invention was developed in view of the above circumstances, and is a cleaning method that effectively prevents toner from scattering and reliably collects it on a magnetic brush through simple and rational improvements. The purpose is to provide equipment.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides the cleaning device described at the beginning, in which the rotation axis of the elastic blade is positioned upstream of the elastic blade in the direction of rotation of the photoreceptor. At the same time, a wind shielding member that forms a space for preventing toner scattering caused by wind by the elastic blade is connected to hang down near the rotation axis so as to rotate together with the rotation axis. The present invention is characterized in that the tip of the wind shielding member is configured to be in contact with or close to the surface of the photoreceptor in the second attitude of the elastic blade.

[Operation] According to the above characteristic configuration, the elastic blade is
During the cleaning process in which the photoconductor surface is blocked from remaining toner by changing its posture, a wind shielding member provided upstream of the photoconductor in the direction of rotation of the photoconductor prevents the wind generated as the photoconductor rotates. This effectively prevents wind from entering the toner scattering prevention space formed by the wind shielding member and the elastic blade.

On the other hand, in order to collect the blocked toner with a magnetic brush as the photoreceptor rotates, the tip of the wind shield member is brought into contact with or close to the surface of the photoreceptor while the elastic blade is switched to the second attitude. Therefore, the intrusion of wind into the toner scattering prevention space is prevented or suppressed.

[Example] Hereinafter, an example of the present invention will be described based on the drawings.

FIG. 1 shows a schematic structure of an image forming section of an electrostatographic copying machine equipped with a cleaning device 1 according to the present invention. , the transfer paper separation roller 7, the static eliminator 7', and the cleaning device 1,
They are arranged in this order in the rotational direction of the photoreceptor 2.

Reference numeral 11 denotes a rotation shaft parallel to the rotation axis of the photoreceptor 2 and disposed on a vertical line 12 passing through the rotation axis 10. As shown in FIG. A holding frame 9 having a U-shaped cross section and spanning almost the entire length of the holding frame 2 is fixed.

Reference numeral 8 denotes an elastic blade for cleaning that constitutes the cleaning device 1, and is made of an elastic material such as urethane rubber, and is attached to the rotation shaft 1 with respect to the holding frame 9.
1 in the rotational direction of the photoreceptor 2 and so that the tip of the blade contacts the surface of the photoreceptor 2 at an angle α of about 10 degrees with the vertical line 12. attached.

As the rotation shaft 11 rotates, the tip of the blade contacts the surface of the photoreceptor to block residual toner on the surface of the photoreceptor, and the blocked toner is transferred to the photoreceptor 2. As the blade rotates, it is configured to be switched to a second position (not shown) in which the tip of the blade is separated from the surface of the photoreceptor so that it can be collected by the magnetic brush 19 of the developing device 5.

Reference numeral 13 denotes a wind shielding member made of an elastic material such as urethane rubber, which is formed considerably thinner than the elastic blade 8, and is attached to the holding frame 9 while being positioned between the rotating shaft 11 and the elastic blade 8. It is detachably attached.

More specifically, the wind shielding member 13 is
The wind shielding member 13 is rotated integrally with the windshield member 13.
is connected to hang down from the holding frame 9 near the rotating shaft 11, and the tip of the wind shielding member 13 is brought into contact with the surface of the photoreceptor while the elastic blade 8 is in the first position.

When the elastic blade 8 is switched to the second posture, the tip of the wind shielding member 13 also moves upward, but the wind shielding member 13 is moved to the side of the rotation shaft 11 relative to the elastic blade 8. Therefore, the amount of upward movement of the tip of the wind shielding member 13 due to the rotation of the rotation shaft 11 is extremely small, and therefore the elastic blade 8 is placed in the second position. Even if the switch is made, the wind shielding member 13 against the surface of the photoreceptor
The tip remains in contact. Alternatively, even if they are separated, the distance is small, and the structure is such that the tip of the wind shielding member 13 can be brought close to the surface of the photoreceptor.

Reference numeral 14 denotes a wind shielding case that covers the entire cleaning device 1, and as shown in FIG.
A buffer member 16 made of felt or the like is attached to the lower end of the surface of the photoreceptor 2, and the wind shielding case 14 is placed in contact with the surface of the photoreceptor 2 via the buffer member 16, and the cleaning device 1 as a whole, photoreceptor 2
The structure is designed to protect against wind caused by the rotation of the

The openings at both ends of the holding frame 9 are arranged close to the side plates 15 of the wind shielding case 14,
Also, the side plates 15, the holding frame 9, and the wind shielding member 1
3 and the elastic blade 8, a substantially sealed toner scattering prevention space 17 is formed between the elastic blade 8 and the wind shielding member 13 to prevent the toner from scattering due to wind. be.

Note that 18 in the figure is a weight fixed to the free end side of the holding frame 9, and serves to bring the tip of the elastic blade 8 into contact with the surface of the photoreceptor 2 with an appropriate pressing force. .

Next, to explain the operation, each of the steps of charging, exposure, development, transfer, separation, and charge removal are performed by the first rotation of the photoreceptor 2. At this time, the elastic blade 8 is switched to the first attitude, and the tip of the elastic blade 8 is always in contact with the surface of the photoreceptor 2, so that residual toner is removed from the surface of the photoreceptor 2. It will be reliably removed and blocked by the tip of the elastic blade 8.

At this time, the untransferred residual toner that has been neutralized by the static eliminating device (for example, the static eliminating lamp shown in FIG. 1) 7' first comes into contact with the wind shielding member 13 as the photoreceptor 2 rotates. Although the surface of the photoreceptor 2 has been weakened due to static electricity removal, the toner adsorption force still remains, and the wind shielding member 13 itself is quite thin and is attached near the rotating shaft 11. In connection with the fact that the wind member 13 does not have enough pressing force to scrape up the residual toner,
The toner remaining on the surface of the photoconductor passes through the tip of the wind shielding member 13 and enters the toner scattering prevention space 17, where it is scraped off by the elastic blade 8 to which an appropriate pressing force is applied by the weight 18. The elastic blade 8 prevents the photoreceptor 2 from moving downstream in the rotational direction.

On the other hand, the wind generated along the surface of the photoreceptor as the photoreceptor 2 rotates is blocked by the wind shielding member 13 forming the toner scattering prevention space 17. By preventing the toner from entering the toner 17, the toner blocked by the elastic blade 8 will not be scattered due to the influence of wind.

When the first rotation of the photoconductor 2 is completed in this way, the holding frame 9 is rotated at a predetermined timing in the counterclockwise direction, that is, upwardly in the figure, about the rotation shaft 11, and the elastic blade 8 is switched to the second attitude, and the toner that had been blocked by the elastic blade 8 is carried on the surface of the photoconductor and, as the photoconductor 2 rotates, the toner moves between the tip of the blade and the photoconductor. The toner is transported and discharged from the toner scattering prevention space 17 through the gap with the surface, and is collected by the magnetic brush 19 of the developing device 5.

In this case, since the toner scattering prevention space 17 is formed downstream of the vertical line 12 in the rotational direction of the photoreceptor 2, the toner blocked by the elastic blade 8 is reliably removed by the magnetic brush. It will be transported and discharged to the 19 side.

Furthermore, since the tip of the wind shielding member 13 is configured to contact or be close to the surface of the photoconductor when the elastic blade 8 is switched to the second attitude, the elastic blade 8 is switched to the second attitude. Even if the switch is switched to , the intrusion of wind into the toner scattering prevention space 17 is reliably prevented or suppressed, which not only prevents toner scattering due to the influence of the wind, but also prevents the toner in the toner scattering prevention space 17 from collapsing onto the photoreceptor. 2 is reliably prevented from spilling onto the upstream side in the rotational direction.

In the embodiment, an example was described in which the entire process including the cleaning process is completed by two rotations of the photoreceptor 2, but the toner blocked by the elastic blade 8 is Once the photoreceptor 2 is collected by the magnetic brush 19, it is possible to proceed to the next copying process. It becomes possible to increase the copying speed (the number of copies per unit time) without changing the rotational speed of the printer.

Further, although a configuration has been exemplified in which the tip of the wind shielding member 13 is brought into contact with the surface of the photoconductor during cleaning with the elastic blade 8 in the first position, toner scattering occurs when the elastic blade 8 is switched to the first position. As long as the prevention space 17 can be formed, the tip of the wind shielding member 13 may be configured to be close to the surface of the photoreceptor without coming into contact with it.

[Effects of the invention] As explained above, the cleaning device according to the invention arranges the rotating shaft of the elastic blade upstream of the elastic blade in the rotational direction of the photoreceptor, and also uses the elastic blade to prevent wind from blowing. A wind shielding member that forms a toner scattering prevention space is hung down in the vicinity of the rotation axis so as to rotate together with the rotation axis, and when the elastic blade is switched to the second posture, The wind shielding member is characterized in that the tip thereof is configured to contact or be close to the surface of the photoreceptor, and the elastic blade is
Not only when the elastic blade is in this position, but also when the elastic blade is switched to the second position, the wind generated due to the rotation of the photoreceptor is blocked by the wind shielding member, so that the influence of the wind is suppressed on the toner. The scattering of the toner in the scattering prevention space can be prevented, and the scattering of the toner blocked by the elastic blade or the toner carried on the surface of the photoreceptor and collected by the magnetic brush can be reliably prevented, and the scattering of the toner can be reliably prevented. Trouble caused by scattered toner, such as dirt or equipment failure, can be avoided.

Furthermore, by effectively utilizing the configuration in which the elastic blade is rotated, the wind shielding member is provided near the rotation axis so that the wind shield member rotates together with the rotation axis. The number of parts can be reduced by eliminating the need for special parts for mounting the parts, and it is also easy to assemble the wind shielding member to the cleaning device. Overall, the wind shielding member, which is simple in shape, can be placed near the axis for rotating the elastic blade. By making a simple and rational improvement by simply connecting the toners in a hanging manner, the problem of toner scattering could be solved at a low cost.

[Brief explanation of drawings]

FIG. 1 is a schematic vertical cross-sectional view showing the image forming section of an electrostatographic copying machine, FIG. 2 is a partially cutaway perspective view showing the main parts of the cleaning device, and FIG.
FIG. 2... Photoreceptor, 5... Developing device, 8... Elastic blade for cleaning, 11... Rotating shaft, 13
... Wind shielding member, 17 ... Toner scattering prevention space,
19...Magnetic brush.

Claims (1)

[Scope of utility model registration request] An elastic blade for cleaning is provided above the photoconductor and upstream in the rotational direction of the photoconductor with respect to the magnetic brush developing device, and is rotatable around a rotation axis parallel to the rotation axis of the photoconductor. The elastic blade is placed in a first position in which the tip of the blade is brought into contact with the surface of the photoconductor to block residual toner on the surface of the photoconductor, and the blocked residual toner is collected by a magnetic brush of a developing device as the photoconductor rotates. In the cleaning device configured to be able to freely switch to a second posture in which the tip of the blade is separated from the surface of the photoconductor so as to cause the blade to move, the rotation axis of the elastic blade is disposed upstream of the elastic blade in the rotational direction of the photoconductor; , a wind shielding member that forms a space for preventing toner scattering caused by wind by the elastic blade is connected to hang down near the rotation axis so as to rotate together with the rotation axis; A cleaning device characterized in that, in the second attitude of the blade, the tip of the wind shielding member is brought into contact with or close to the surface of the photoreceptor.