JP2868051B2 - Electrophotographic equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic apparatus, and more particularly, to an apparatus for collecting residual toner remaining at the end of a photosensitive member.

[0002]

2. Description of the Related Art An apparatus disclosed in Japanese Patent Application Laid-Open No. 62-144180 is known as an apparatus for recovering residual toner remaining on the end portion of a photoreceptor after completion of a developing step in electrophotography. In this apparatus, the blade provided in the developing device is brought into contact with the end portion of the photoconductor immediately after the development is completed, and further, as the photoconductor carrier moves, the blade continuously contacts from the end portion of the photoconductor to the surface of the photoconductor carrier. The photosensitive member is brought into contact with the blade and finally sucked by a suction member provided on the surface of the photosensitive member remaining between the blade and the photosensitive member.

[0003]

In the above-mentioned conventional residual toner collecting device, the blade is rubbed against the photoconductor carrier, so that the residual toner adheres to the surface of the photoconductor carrier, and the multicolor (2) In the case of using (color or more), the colors are mixed through the blade, so that a cleaning means for the blade surface is required. Further, since the final treatment is performed by suction, a suction path, a suction pump, a liquid separator, and the like are required. And the cost increases.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a method for separating a rear end on which a charge latent image is formed on a surface.
In this state, the forward and reverse rotatable drum having a suction portion for adsorbing the central portion of the photoconductor, and the charge latent image formed on the photoconductor at the time of normal rotation of the drum are developed. An electrophotographic apparatus having a configuration in which a drum is rotated in a reverse direction to remove toner remaining on a photoconductor, wherein the drum is not brought into contact with the photoconductor during normal rotation, and is separated from the drum during reverse rotation. At the rear end, a blade formed in a substantially rectangular shape to be brought into contact with the surface opposite to the surface having the charge latent image, and when the drum is reversed, the blade is brought into contact with the photoreceptor. And an air squeezing nozzle for blowing air to the optical member to blow residual toner on the photosensitive member toward the blade.

[0005]

[Action] The drum is reversed, and the blade is moved to the rear end of the photoconductor.
In contact with the surface opposite to the surface having the charge latent image
In this state, the blade blows the residual toner blown to the rear end of the photoreceptor by the air blown out from the air squeeze nozzle, thereby completely removing the residual toner from the photoreceptor.

[0006]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Here, FIG. 1 is a side view of the electrophotographic apparatus according to the present invention in a developing step, FIG. 2 is a front view of the electrophotographic apparatus at a fixed position of a developing device, FIG. Is a front view in a standby state, FIG. 5 is a front view in a toner collecting process,
6 is an enlarged view of a main part of FIG. 3, FIG. 7 is an enlarged view of a main part of FIG. 4, and FIG. 8 is an enlarged view of a main part of FIG.

Below the photosensitive drum 1, three-color developing units 2, 2, and 2 are provided by a moving chain 3 so as to be movable in a direction orthogonal to the axial direction of the drum 1. As shown in FIG. 8, the photoreceptor drum 1 is formed by adsorbing a photoreceptor 5 on the surface of a drum 4 which is a photoreceptor carrier. Suction unit
Is provided with a photosensitive member suction pad 4b. Here, an end portion 5a as a rear end of the photoconductor 5 (see FIG. 8)
Are held in a state of floating above the surface of the drum 4.

Each developing unit 2 has a drum 1 in an electrode case 6.
The electrode 7 is provided along the axial direction of FIG.
As shown in the figure, the end portion 5a of the photoconductor 5 of the photoconductor drum 1
The blade 8 formed in a substantially rectangular shape for removing the residual toner T remaining on the photosensitive member 5 in the toner collecting step is used.
Is provided so as to come into contact with . A developer inlet 9a and a developer outlet 9b are provided on the side of each developing unit 2.

The photosensitive drum 5 is located below the photosensitive drum 1.
In the vicinity of the end portion 5a , the end of the photoconductor 5 is collected in the toner collecting process.
An air squeeze nozzle 10 for blowing air to the end portion 5a is provided.

Below the developing units 2, there is provided a vertical moving mechanism 11 for moving each developing unit 2 up and down. The vertical movement mechanism 11 includes a vertical guide shaft 1 erected on a base 12.
The upper and lower guide ball bushings 15 attached to the upper and lower plates 14 are slidably fitted in 3.

The roller stand 1 is placed on the upper and lower plates 14.
6 and stand on the upper end of the roller stand 16 for developing.
Rollers 18 engageable with the engaging grooves 17 of the containers 2, 2, 2
Is rotatably supported, and the roller stand 16 has approximately L
A L-shaped lever 19 is pivotally supported by a lever shaft 21, and a lever roller 22 is rotatably supported at the upper end of the lever 19.

A cam shaft 24 is rotatably supported between support plates 23 erected on the base 12 below the upper and lower plates 14, and the cam shaft 24 moves the upper and lower plates 14 up and down. 25 and LES rocking the lever 19
A bar cam 26 is fixedly arranged, a phase detection sensor 27 (FIG. 1) is arranged on one end of the cam shaft 24, and a driving force transmission gear 28 is fixed on the other end.

On both sides of the photosensitive drum 1, as shown in FIG.
Is arranged.

The operation of the electrophotographic apparatus constructed as described above will be described. As shown in FIG. 2, the moving chain 3 is driven so that the required developing unit 2 is in a fixed position, and the photosensitive drum 1 is moved. When the start end of the photoconductor 5 reaches just below the photoconductor drum 1 with the rotation, the cam shaft 24 is driven to rotate as shown in FIGS. 1, 3, and 6, and the upper and lower cams 25 and the lever cam 26 are moved. By rotating, the upper and lower plates 14 are raised.

Thus, the upper and lower rollers 18 move the developing device 2
Engages the engagement groove 17, with the lever roller 22 comes into contact with the lower surface of the developing unit 2, the developing device 2 is increased with increasing vertical plate 14, the developing device 2 of the electrode 7 and the electrode positioning roller The developing unit 2 develops the image area by engaging with the developing unit 2.

Thereafter, the lever cam 26 is rotated to swing the lever 19, and as shown in FIGS.
Is lowered while being slightly inclined, and stopped until the end portion 5a of the photoconductor 5 of the photoconductor drum 1 passes the position of the blade 8.

The end of the photosensitive drum 5 of the photosensitive drum 1
When the portion 5a passes through the position of the blade 8, the developing device 2 is raised while being tilted as shown in FIGS. 5 and 8, and then the photosensitive drum 1 is rotated in a direction opposite to the process traveling direction. 8, the end portion 5a of the photoreceptor 5 as shown in FIG.
Is brought into contact with the blade 8.

Here, by blowing air from the air squeezing nozzle 10 to the end portion 5a of the photoreceptor 5, the residual toner in the end portion 5a of the photoreceptor 5 is transmitted to the blade 8 to collect the residual toner. .

In this case, the residual toner is more easily transmitted to the blade 8 by applying a bias voltage to the blade 8. By not applying this bias potential except when necessary, the blade 8
It is possible to suppress the adhesion and stacking of the toner on the toner.

[0020]

According to the present invention as described above,
When the drum is rotating forward, it does not contact the photoconductor.
At the rear end of the photoconductor separated from the ram and has a charge latent image
Bent in a substantially rectangular shape to abut the opposite surface
The blade is brought into contact with the photoreceptor by rotating the drum and the drum
Blow air to the photoconductor with the
Air squeeze nose that blows toner toward the blade
Since a and Le, can be flowed transfer the residual toner were received blown to the rear end of the photoreceptor blade by the air blown from the air squeeze nozzle, to completely remove the residual toner from the photoreceptor. For this reason, it is possible to prevent the residual toner from remaining on the photoconductor and deteriorating the quality of the electronically recorded image. Further, since the blade can remove the residual toner without directly touching the surface on which the charge latent image is formed, the electrophotographic image obtained on the photoconductor is not damaged. Therefore, a high-quality electronic image can be obtained.

[Brief description of the drawings]

FIG. 1 is a side view of an electrophotographic apparatus according to the present invention in a developing process.

FIG. 2 is a front view of the electrophotographic apparatus at a fixed position of a developing device.

FIG. 3 is a front view in a developing process.

FIG. 4 is a front view in a standby state.

FIG. 5 is a front view in a toner collecting step.

FIG. 6 is an enlarged view of a main part of FIG. 3;

FIG. 7 is an enlarged view of a main part of FIG. 4;

FIG. 8 is an enlarged view of a main part of FIG. 5;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Photoreceptor drum, 2 ... Developing device, 4 ... Drum, 4b ... Absorption
Attachment part (pad for adsorbing photoreceptor) , 5: photoreceptor, 5a: rear end (end part), 8: blade, 10: nozzle for air squeezing, T: residual toner

Claims (1)

(57) [Claims] 1. After a photoreceptor having a charge latent image formed on its surface
With the ends separated, a forward / reversely rotatable drum having an adsorbing portion for adsorbing the central portion of the photoreceptor, and an electric charge latent formed on the photoreceptor when the drum is normally rotated. An electrophotographic apparatus having a configuration in which an image is developed, and after completion of the development, the drum is rotated in a reverse direction to remove toner remaining on the photoconductor. without, at the rear end of the photosensitive member spaced from the drum to the reverse rotation, and is reversed and the blade bent and formed into substantially V-shape is brought into contact with the surface opposite to the a surface of the latent image, the drum Bring the blade into contact with the photoreceptor
And an air squeezing nozzle for blowing air to the photoreceptor to blow residual toner on the photoreceptor toward the blade.