JPH0326525Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Prior Art) Generally, in an image forming apparatus to which a corona discharge device is applied, contaminants such as toner and dust are floating in the apparatus. As image formation continues for a long time, this contaminant adheres to the corona discharge electrode of the corona discharge device. Due to the adhesion of this contaminant, discharge efficiency decreases and discharge unevenness occurs, resulting in a decrease in image quality.
Therefore, it becomes necessary to periodically clean the corona discharge electrode.

Conventionally, as a method for cleaning a corona discharge electrode, as described in "IBM Technical Disclosure Bulletin Vol. The cleaning frame moves with the cleaning frame movably disposed on the surface of the corona discharge electrode, and while wiping off the particles adhering to the surface of the corona discharge electrode, the particles are transported to both ends of the corona discharge device where they do not substantially affect the image. Some devices have made it possible to maintain a uniform corona discharge current flowing to a member to be charged by keeping the corona discharge electrode in a clean state at all times. but,
This cleaning pad does not effectively remove particles on the surface of the corona discharge electrode, but can simply move the particles from one position on the corona discharge electrode to another by absorption into the cleaning pad. Therefore, as the number of cleanings increases, the cleaning performance of the cleaning pad decreases.
The cleaning pad itself needs to be cleaned or replaced. Also, the frequency is high.

Also, as described in Japanese Patent Application Laid-open No. 54-51851,
The height of the corona discharge electrode can be adjusted by separating the sliding member of the cleaning member from the corona discharge electrode when not cleaning by engaging the elastic part of the cleaning member with the protrusion provided at the end of the corona discharger. However, if the rubbing member is always separated from the corona discharge electrode when not being cleaned, cleaning may become difficult as the ambient temperature of the corona discharger in the image forming apparatus increases. There was a fear that the elastic portion of the member would be deformed or sag, making it impossible to clean the corona discharge electrode properly for a long period of time.

(Object of the invention) The present invention has been made in view of the above-mentioned points, and an object of the present invention is to provide a corona discharge device equipped with a corona discharge electrode cleaning means that solves the conventional drawbacks.

(Summary of the invention) That is, the present invention provides a corona discharge device having a corona discharge electrode and a shield member surrounding the corona discharge electrode and having at least an opening for corona discharge. A cleaning means that contacts along the
A cleaning means having a rubbing member that rubs a corona discharge electrode during cleaning, and a support member that elastically supports the rubbing member, and when not cleaning, the rubbing member is separated from the corona discharge electrode at least once at an end. and an engaging means that engages the supporting member so that the sliding member subsequently contacts the corona discharge electrode at a predetermined position at the end.

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

FIG. 1 is an external perspective view showing an embodiment of the corona discharge device of the present invention, and FIG. 2 is a partial side view thereof. The corona discharge device 10 has a generally U-shaped shield 1, 2 of conductive material and insulating end blocks 7, 8 for supporting a corona discharge wire 6 as a corona discharge electrode within the shield. . Further, in order to enable the cleaning member 4 to move in the longitudinal direction along the corona discharge electrode 6, a shield back plate 2 is provided.
A slot 3 is provided in the leg 4 of the cleaning member 4.
a, 4a are engaged with the two slots 3. The cleaning member 4 is integrated with a handle (not shown) through a connecting rod 9, and by operating the handle, the cleaning member 4 can be moved along the longitudinal direction of the corona discharge electrode. Note that it is also possible to move the cleaning member 4 itself by holding it by hand without providing a connecting rod or a handle. Also, an insulating end block 8 on the side where the cleaning member 4 is housed when not cleaning.
A protruding pin 5 is provided at , and when the cleaning member 4 moves in the direction of arrow A in FIG. , 4b, and are arranged so that the elastic portion 4b and the protruding pin 5 are engaged with each other. Incidentally, FIG. 3 is a sectional view of the cleaning member 4 at the time of cleaning the corona discharge electrode.

Further, the cleaning member 4 has two legs 4a, 4a and a cleaning pad 11, which is a member for cleaning the corona discharge electrode by rubbing, is attached to the tip of the elastic part 4b, 4b which is divided into two legs. The shape of the cleaning member 4 is set so that the corona discharge electrode 6 is disposed approximately in the center of the pad 11. Further, the contact pressure of the pad 11 that provides a preferable cleaning effect on the corona discharge electrode 6 is set depending on the material of the cleaning member 4, the length of the elastic portion 4b, the thickness of the pad 11, etc.

By sandwiching the corona discharge electrode 6 with the cleaning pads 11 and moving the cleaning member 4 in the longitudinal direction of the corona discharge electrode while pressing them with the contact pressure, particles such as toner and dust attached to the surface of the corona discharge electrode 6 are removed from the pads. 11, it is carried to the end of the corona discharge electrode while being wiped and collected. On the other hand, the protruding pin 5 integrally molded with the insulating end block 8 or attached to the block 8 pushes out the elastic part 4b of the cleaning member 4, so that the pressing of the cleaning pad 11 against the corona discharge electrode 6 is released. The carried particles fall under their own weight and are removed from the corona discharge electrode. FIG. 4 shows a cross-sectional view of the cleaning member 4 when the pressure on the corona discharge electrode is released.

Further, when the cleaning member 4 is pushed in the direction of arrow A in FIG. Then, the pressing state on the corona discharge electrode is restored. In this case, groove 5
The diameter of a is determined by the elastic member 4 when cleaning the corona discharge electrode.
By making the distance smaller than the distance between b and 4b, the elastic part 4
By holding the cleaning member in this state during non-cleaning and when the image forming apparatus is in operation, the stress at the fixed end of b can be suppressed to a minimum, thereby preventing deformation of the elastic portion 4b of the cleaning member 4 due to an increase in the ambient temperature of the corona discharge device. Can prevent sagging. Furthermore, since the cleaning pad can be kept in contact with the corona discharge electrode, it can be expected to be effective in preventing vibration of the corona discharge electrode.

Next, modified examples of the shape of the protruding pin 5 are shown in FIGS. 5 and 6.

If the protruding pin 5 is made into a stepped shape as shown in Fig. 5,
When the cleaning member 4 is moved within the range of the protruding pin, vibration is excited in the elastic part 4b of the cleaning member 4,
A greater particle removal effect can be expected.

Further, in FIG. 6, the protruding pin 5 is provided with several grooves 5a. When the cleaning member 4 is moved within the range of this protruding pin, vibrations are excited in the elastic part 4b and the cleaning pads 11 sandwiching the corona discharge electrode 6 from both sides collide, causing the pads 11 to vibrate. Adhering particles can be brushed off.

In both the modified examples shown in FIGS. 5 and 6, the cleaning member 4 is held in the groove 5a of the protruding pin 5 provided on the insulating end block 8 when the image forming apparatus is not being cleaned or when the image forming apparatus is in operation. Since the cleaning pads sandwich the corona discharge electrode, it is possible to prevent the elastic portion 4b of the cleaning member 4 from being deformed or set, and furthermore, since the cleaning pads sandwich the corona discharge electrode, vibration of the corona discharge electrode can also be prevented.

Incidentally, in the above embodiment, an example of a cleaning member provided with a plurality of corona discharge electrodes and a plurality of cleaning pads for cleaning each of the corona discharge electrodes was shown, but in the present invention Of course, it is also possible to use a cleaning member with one discharge electrode and one cleaning pad correspondingly.

Further, in the above embodiment, the cleaning member is moved manually, but by detecting that a predetermined image forming operation has been completed, a driving means such as a motor is driven, and the cleaning member is thereby moved. It is also possible to clean the discharge wire by automatically moving the discharge wire.

In addition, in the part of the cleaning member that comes into contact with the shield,
If a rubbing member such as the cleaning pad is provided, the shield can be cleaned.

(Effects of the invention) As explained above, according to the invention, contaminants can be reliably cleaned and removed from the corona discharge electrode, and the elastic portion of the cleaning member is not deformed or worn out. The corona discharge electrode can be cleaned well over a long period of time. Furthermore, since the rubbing member is in contact with the corona discharge electrode during non-cleaning, vibration of the corona discharge electrode can also be prevented.

[Brief explanation of the drawing]

Fig. 1 is an external perspective view showing an embodiment of the corona discharge device of the present invention, Fig. 2 is a partial side view of the corona discharge device, Fig. 3 is a sectional view of the cleaning member when cleaning the corona discharge electrode, and Fig. 4 The figure is a cross-sectional view showing a state when the protruding pin is engaged with the cleaning member, and FIGS. 5 and 6 are side views showing modified examples of the protruding pin. 4...Cleaning member, 5...Protrusion pin, 6...Corona discharge electrode, 11...Cleaning pad.

Claims (1)

[Claims for Utility Model Registration] A corona discharge device having a corona discharge electrode and a shield member surrounding the corona discharge electrode and having at least an opening for corona discharge. a cleaning means that comes into contact with the
A cleaning means having a rubbing member that rubs a corona discharge electrode during cleaning, and a support member that elastically supports the rubbing member, and when not cleaning, the rubbing member is separated from the corona discharge electrode at least once at an end. and engaging means that engages the supporting member so that the sliding member thereafter contacts the corona discharge electrode at a predetermined position at the end. (Technical Field) The present invention relates to a corona discharge device, and particularly to a corona discharge device provided with a cleaning means for cleaning a corona discharge electrode of the corona discharge device.