JPH08137287A - Excess developer removing device - Google Patents

Abstract

PURPOSE: To prevent the developer clogging (toner clogging) in the tip end part of a nozzle in an excess developer removing device provided with the nozzle for ejecting the air into the vicinity of a developing device. CONSTITUTION: The excess developer removing device for removing the excess developer stuck on the photosensitive material 2 by ejecting the air from the nozzle 20a of the wind pressure unit 20 arranged on the downstream side in the transferring direction of the photosensitive material 2 from the developing device 16, by winding the photosensitive material 2 recording the latent image on the rotary drum 6, integrally transferring these with the rotary drum 6, and at the time of developing the recorded latent image to the visual image by the developer supplied from the developing electrode 16a inside the developing device 16 arranged close to the rotary drum 6, is provided with the nozzle moving forwards and backwards means 50 capable of freely moving forwards and backwards the nozzle 20a so as to come close to the developing electrode 16a in the midst of developing the photosensitive material 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an excess developer removing device provided with a nozzle for blowing air in the vicinity of a developing device, and in particular, clogging of the developer (toner clogging) at the tip of the nozzle.
The present invention relates to an excessive developing solution removing device configured to prevent the above.

[0002]

2. Description of the Related Art In a wet electrophotographic apparatus in which an electrostatic latent image is recorded on a photosensitive material and the electrostatic latent image is developed by a wet developing device to be visualized, after passing through the developing device. Inevitably, the developing solution (toner) remains on the surface of the photosensitive material (image carrier), and if this residual developing solution (hereinafter referred to as excess developing solution) is left unattended, the quality of the completed image deteriorates. The inconvenience occurs. For this reason, the applicant of the present invention has previously proposed, in Japanese Unexamined Patent Publication No. 6-51642, an excess developer removing device provided with a nozzle for blowing air in the vicinity of the developing device.

FIG. 4 is a side view for explaining a conventional excess developer removing device.

A conventional excess developer removing device 1 shown in FIG.
00 is disclosed in Japanese Patent Laid-Open No. 6-51642, and will be briefly described here.

In FIG. 1, in a conventional excess developing solution removing apparatus 100, a photosensitive material 101 having an electrostatic latent image recorded thereon is wound around a rotary drum 102 and is rotationally transferred together with the rotary drum 102 in a direction of an arrow A. Has been done. Further, below the rotary drum 102, a developing device 103 for developing the photosensitive material 101 is provided so as to be movable back and forth (movable up and down) in a direction perpendicular to the rotary drum 102 (directions of arrows B ₁ and B ₂ ). There is.

Here, the developing device 103 is connected to the rotary drum 1
02, the long developing electrode 103 along the shaft 102a of the rotary drum 102 provided in the developing device 103.
The developer supplied from a is brought into contact with the photosensitive material 101 to visualize the recorded electrostatic latent image, and the developer overflowing from the developing electrode 103a is collected by the developer collecting drain 10
Recovered in 3b. In addition, the photosensitive material 1 from the developing device 103
Nozzle 1 for blowing air to the downstream side of 01 in the transfer direction
A blower 104 provided with 04a is provided, and the excess developing solution adhering to the photosensitive material 101 during development on the photosensitive material 101 is blown off by the air blown from the nozzle 104a and collected by the developing solution collecting drain 103b. ing.

[0007]

By the way, in the above-mentioned conventional excess developer removing device 100, the excess developer adhering to the photosensitive material 101 is blown off by the air blown from the nozzle 104a of the blower 104, and the developing device is removed. 103
Although the excess developer (excess toner) is prevented from remaining on the surface of the photosensitive material 101 after passing through the sheet, the tip portion of the nozzle 104a has a developing electrode 103a in the developing device 103.
Since a portion of the developing solution overflowing from the developing electrode 103a enters the nozzle 104a and causes clogging of the developing solution (toner clogging) at the tip of the nozzle 104a, the air is not blown out. Is occurring. Here, although it is considered that clogging of the developing solution in the nozzle 104a can be avoided by increasing the wind pressure (air pressure) of the blower 104, if the wind pressure is too strong, the photosensitive material 101 is adversely affected, and therefore the wind pressure is It is suppressed to the extent that excess developer can be removed.
The clogging of the developer with 4a cannot be avoided.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, an excess developing solution removing apparatus according to the present invention is a rotatable rotary drum for winding a photosensitive material having a latent image recorded thereon and transferring the photosensitive material integrally. And a developing device capable of advancing and retreating with respect to the rotating drum and having a developing electrode therein, and supplying the recorded latent image from the developing electrode with the developing device being close to the rotating drum. When a visible image is developed with the developed developer, the excess developer adhering to the photosensitive material is removed with air blown from a nozzle provided downstream of the developing device in the transfer direction of the photosensitive material. In the above, the nozzle advancing / retreating means is provided so as to move the nozzle closer to the developing electrode only during the development of the photosensitive material.

Further, in the excess developer removing device, the nozzle advancing / retreating means uses the same drive source as the developing device advancing / retreating means for advancing / retreating the developing device, and the drive source and the developing device advancing / retreating cam and the nozzle advancing / retreating. It is characterized in that the use cams are provided in phase with each other.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the excess developer removing device according to the present invention will be described in detail below with reference to FIGS.

FIG. 1 is a block diagram for explaining an excessive developing solution removing device according to the present invention, FIGS. 2A and 2B are diagrams for explaining the operation of the excessive developing solution removing device, and FIG. 6 is a timing chart showing operation timings of main part members in the same excess developer removing device.

The excess developer removing device 1 according to the present invention shown in FIG. 1 is constructed as a wet electrophotographic device.
A photosensitive material 2 is mounted in a state of being rolled into a roll in the excess developer removing device 1. The photosensitive material 2 is composed of a pair of rollers 3 and a pair of rollers 4 and is a rotary drum described below. 6, is further pressed against the rotating drum 6 by the pressing roller 5, and the suction force is applied by the operation of a suction device (not shown) in the rotating drum 6, while the rotating drum 6 is wound around the rotating drum 6. And is integrally rotated in the counterclockwise direction (direction of arrow A) in the figure. After that, the photosensitive material 2 is cut into a predetermined length by a cutter 7 provided between the rollers 3 and 4.

Further, the photosensitive material 2 transferred integrally with the rotating drum 6 is a charger 8 provided upstream of the photosensitive material 2 in the transfer direction.
Thus, the rotary drum 6 is uniformly charged as the rotary drum 6 rotates.
Then, the image signal output from the semiconductor laser 9 is rotated by the rotatable polygon mirror 10 to the shaft 6a of the rotary drum 6.
Is scanned line by line to irradiate the charged photosensitive material 2 through the lens 11 and the reflecting mirrors 12 and 13 sequentially to perform exposure, and an electrostatic latent image corresponding to an image signal is recorded as a charge image. are doing.

Further, a pre-bath 14 for eliminating unevenness in density is provided downstream of the charger 8 in the transfer direction of the photosensitive material 2, and the pre-bath taken in from a liquid supply means (not shown)
It is poured onto the outer peripheral surface of the roller 14a and applied so as to cover the charge image.

Further, a terminal toner removing device 15 is provided downstream of the pre-bath device 14 in the transfer direction of the photosensitive material 2, and a cleaning member 15a wound like a roller is provided with the photosensitive material 2 via an arm 15b. By attaching to the terminal part of
As will be described later, the excess developing solution (excess toner) attached to the end portion of the photosensitive material 2 can be removed during a plurality of times of development.

Further, the photosensitive material 2 is fed from the end toner removing device 15.
One of the plurality of developing devices 16 to 19 is provided directly below the rotary drum 6 on the downstream side in the transport direction of the developing device 16 (to 19).
Is provided so as to be movable back and forth (movable up and down) in the vertical direction (directions of arrows B ₁ and B ₂ ) with respect to the rotary drum 6. The plurality of developing devices 16 to 19 have long developing electrodes 16a to 19a provided along the shaft 6a of the rotary drum 6 therein, and color develop the electrostatic latent image recorded on the photosensitive material 2. When a visible image is formed by developing, the developing device 16 is a developing solution for yellow (Y), the developing device 17 is a developing solution for magenta (M), and the developing device 18 is a developing solution for cyan (C). The container 19 is prepared as a developing solution for black (B). Then, of the plurality of developing devices 16 to 19, one developing device 16 (to 1
9) is selectively mounted on the developing device mounting table 34 described later. At this time, when the electrostatic latent image recorded on the photosensitive material 2 is developed for each color, the developing device advancing / retreating means 30 to be described later moves the developing device 16 for the first color yellow (Y) to just below the rotary drum 6. The developing solution for yellow (Y) is brought into contact with the photosensitive material 2 from the developing electrode 16a in the developing device 16 to develop the electrostatic latent image into yellow, and thereafter, each time the rotary drum 6 rotates. Developing device 17 for magenta (M), cyan (C)
The developing device 18 for black and the developing device 19 for black (B) can successively and repeatedly perform color development.

Further, a blower 20 equipped with a nozzle 20a for blowing out air is provided downstream of the one developing device 16 (to 19) which has risen substantially just below the rotary drum 6 in the transfer direction of the photosensitive material 2. Developing electrode 16a in the container 16 (to 19)
(Through 19a) is provided retractably in the horizontal direction (arrow _X 1 _{X 2} direction) with respect to, and, only during the development of the photosensitive material 2 as will be described later, developed nozzle 20a of the blower 20 Developing electrode 16a (~ 19a) in the container 16 (~ 19)
Is a main part of the excess developer removing device 1 according to the present invention, and the nozzle advancing / retreating means 50 for allowing the nozzle 20a to advance / retreat will be described later together with the developing device advancing / retreating means 30.

Further, a dryer 21 for drying the developed photosensitive material 2 is provided downstream of the nozzle 20a of the blower 20 in the transfer direction of the photosensitive material 2, and a dryer 21 for removing the charge of the charged photosensitive material 2 is provided. A static eliminator 22 is provided respectively. Further, a pair of rollers 23 is provided on the upper left side of the rotary drum in the figure for discharging the photosensitive material 2 which has been developed.

Next, the developing device advancing / retreating means 30 and the nozzle advancing / retreating means 50, which are essential parts of the present invention, will be described.

First, the developing device advancing / retreating means 30 comprises the base 3
A plurality of guide shafts 32 (only two shown) on one
33 is erected, and these plural guide shafts 32,
A developing device mounting table 34 for selectively mounting a plurality of developing devices 16 (to 19) is fitted to 33 so as to be movable up and down. Further, a cam support plate 35 is erected on the base 31, and a motor 36 as a drive source and a rotary shaft 37 which is rotationally driven via a reduction means (not shown) are rotatable on the cam support plate 35. Supported by. A developing device advancing / retreating cam 38 and a nozzle advancing / retreating cam 39 are fixed to the rotating shaft 37 in phase with each other. Further, a substantially V-shaped developing device advancing / retreating lever 40 is rotatably supported on the cam support plate 35 about a shaft 41, and the developing device advancing / retreating lever 40 is also provided.
Is a roller 42 that abuts the developing device mounting table 34 at one end.
And a cam follower 43 that comes into contact with the developing device advancing / retreating cam 38 is provided at an intermediate portion. When the developing device advancing / retreating cam 38 is rotated, the cam follower 43 provided at the intermediate portion of the developing device advancing / retreating lever 40 rotates about the shaft 41 while following the developing device advancing / retreating cam 38. A developing device mounting table 34 on which the developing device 16 (to 19) is mounted via a roller 42 provided at one end of the advancing / retreating lever 40.
Is designed to move up and down.

Next, in the nozzle advancing / retracting means 50, the blower 20 having the nozzle 20a on the blower mounting table 51 moves forward / backward with respect to the developing electrode 16a (~ 19a) in one developing device 16 (~ 19). Horizontal direction (arrow X ₁ , X ₂ direction)
It is mounted so that it can move freely. Further, the blower 20 is provided with a positioning pin 20b at one end on the rotary drum 6 side,
Moreover, an L-shaped engagement plate 20c is provided at the other end, and the other end side is pressed against the rotary drum 6 side by the compression spring 52, so that the tip of the positioning pin 20b is brought into contact with the stopper surface 51a of the blower mounting table 51. Contact the nozzle 20a of the blower 20
As will be described later, the tip end of the is positioned at a position near the developing electrode 16a (to 19a) in the developing device 16 (to 19). In addition, the cam support plate 35 described above is provided with an inverted U-shaped nozzle advancing / retreating lever 53 on a shaft 54.
The nozzle advancing / retreating lever 53 is rotatably supported around the roller 55, which is in contact with one end of the L-shaped engaging plate 20c of the blower 20 from the inside, and the shaft 54.
A cam follower 56 that comes into contact with the nozzle advancing / retreating cam 39 is provided at the other end portion through. When the nozzle advancing / retreating cam 39 is rotated integrally with the developing device advancing / retreating cam 38, the cam follower 56 provided at the other end portion of the nozzle advancing / retreating lever 53 is centered on the shaft 54 along the nozzle advancing / retreating cam 39. Since it rotates, the nozzle advancing / retreating lever 53
The nozzle 20a of the blower 20 is connected to the developing electrode 16a in the developing device 16 (to 19) through the roller 55 provided at one end portion of
(~ 19a) can be moved forward and backward.

In the embodiment, the nozzle 20a is connected to the blower 20.
However, the blower 20 serving as an air supply source is separated from the separate nozzle (not shown), and a flexible pipe (not shown) is provided between the blower 20 and the separate nozzle. No.) and only the nozzle is connected to the developing device 16 (~ 1
A method is also conceivable in which the developing electrode 16a (to 19a) in 9) can be moved forward and backward.

As described above, the developing device advancing / retreating means 30 and the nozzle advancing / retreating means 50 have a developing device advancing / retreating cam 38 and a nozzle advancing / retreating cam 39 on an output shaft (rotating shaft) 37 from a motor 36 serving as the same drive source. Since they are provided in phase with each other,
Advancing and retracting the developing device 16 (to 19) and the nozzle 20 of the blower 20
The timing of the advance and retreat of a can be ensured, which can contribute to the improvement of the reliability of the excess developing solution removing apparatus 1 and also contribute to the cost reduction of the excess developing solution removing apparatus 1 because the drive source is shared.

The operation of the excess developing solution removing device 1 by the nozzle advancing / retreating means 50 will be described with reference to FIGS. 2 and 3.

As shown in FIGS. 2A and 3, when the developing device advancing / retreating cam 38 and the nozzle advancing / retreating cam 39 are integrally rotated, the developing device advancing / retreating lever accompanying the rotation of the developing device advancing / retreating cam 38 is rotated. By the rotation of 40 in the ascending direction, the developing device 1 for the first color yellow (Y) mounted on the developing device mounting table 34.
6 rises to just below the rotary drum 6. After the developing device 16 moves up, the developing electrode 16a in the developing device 16 is attitude-controlled with respect to the rotary drum 6 at a predetermined angle by an attitude control means (not shown) over time. Of course, the developing device advancing / retreating cam 38 and the nozzle advancing / retreating cam 39 continue to rotate integrally during the attitude control of the developing electrode 16a. on the other hand,
During the period until the attitude of the developing electrode 16a in the developing device 16 is controlled, the nozzle 20a is integrated with the blower 20 by the rotation of the nozzle advancing / retreating cam 53 in the retreating direction as the nozzle advancing / retreating cam 39 rotates. While resisting the urging force of the compression spring 52, it separates from the developing electrode 16 in the developing device 16 and retreats in the arrow X ₁ direction. Therefore, before the development on the photosensitive material 2, the developing solution is supplied from the developing electrode 16 even during the attitude control of the developing electrode 16, but the developing solution does not enter the retracted nozzle 20a. No clogging of the developing image liquid (toner clogging) occurs at the leading end of 20.

Next, as shown in FIGS. 2B and 3.
When the developing electrode 16a in the developing unit 16 is attitude-controlled with respect to the rotary drum 6 at a predetermined angle, an electrostatic latent image is recorded by using the yellow (Y) developing solution supplied from the developing electrode 16a. The development of the first color yellow (Y) is started on the photosensitive material 2 thus formed. Immediately before the development of the yellow (Y) of the first color is started, the nozzle advancing / retreating lever 53 is rotated in the approaching direction along with the further rotation of the nozzle advancing / retreating cam 39 so as to be integrated with the blower 20. The nozzle 20a is a compression spring 52.
Is moved in the direction of the arrow X ₂ by the urging force of the nozzle 20a.
The leading end of the developing device approaches the developing electrode 16 in the developing device 16. At this time, since the positioning pin 20b provided on the rotary drum 6 side at one end side of the blower 20 is in contact with the stopper surface 51a of the blower mounting table 51 by the urging force of the compression spring 52, the nozzle 20 of the blower 20 is provided. The front end portion of is positioned at a position close to the developing electrode 16a in the developing device 16 with a slight distance therebetween. As described above, the tip end portion of the nozzle 20 of the blower 20 is maintained close to the developing electrode 16a in the developing device 16 only during the development of the first color yellow (Y). The surplus developer adhering to the surface of the photosensitive material 2 after passing through is blown off by the air blown from the nozzle 20a of the blower 20. As a result, it is possible to prevent the excess developer from adhering to the photosensitive material 2 that has completed development.

After that, when the development of the first color yellow (Y) is completed, as shown in FIG.
Due to the further rotation of the nozzle advancing / retreating lever 53 in the retracting direction, the nozzle 20a integrally with the blower 20 separates from the developing electrode 16 in the developing device 16 while resisting the biasing force of the compression spring 52. It is evacuating.

After that, when the development of the first color yellow (Y) is completed, the second color magenta (M) and the third color are applied to the photosensitive material 2 on which the electrostatic latent image is recorded every one rotation of the rotary drum 6. The cyan (C) and the black (B) of the fourth color are repeated in the same manner as above to perform color development.

As described in detail above, in the excess developer removing device 1 according to the present invention, only during the development of the photosensitive material 2,
The nozzle 20a for blowing out air is connected to the developing device 16 (to 1
9) The developing electrode 16a (to 19a) in the inside is approached, and the nozzle 20a is connected to the developing device 16 (to 19) except during the development.
Since it is retracted from the developing electrode 16a (to 19a) inside, the developer supplied from the developing electrode 16a (to 19a) does not enter the retracted nozzle 20a.
The development image liquid clogging (toner clogging) does not occur at the tip of the nozzle 20a, which can contribute to the improvement of the quality and reliability of the excess developer removing device 1.

[0030]

In the apparatus for removing excess developer according to the present invention, which has been described in detail above, according to the first aspect, a nozzle for blowing air is provided in the developing electrode in the developing device only during the development of the photosensitive material. Since the nozzle advancing and retracting means that can move forward and backward is provided so that it can approach, the excess developer adhering to the surface of the photosensitive material after passing through the developing device can be completely removed by the air blown from the nozzle during development, Other than the above, the tip of the nozzle is retracted from the developing electrode, so the developer supplied from the developing electrode does not enter the retracted nozzle, so clogging of the developing image liquid (toner clogging) occurs at the tip of the nozzle. It is possible to contribute to the improvement of the quality and reliability of the excess developing solution removing device without causing it.

According to a second aspect of the present invention, in the excess developer removing device according to the first aspect, the nozzle advancing / retreating means uses the same drive source as the developing device advancing / retreating means for advancing / retreating the developing device, and the developing source is the developing source. Since the cam for advancing and retracting the device and the cam for advancing and retracting the nozzle are provided in phase with each other, the timing of the advancing and retracting of the developing device and the advancing and retracting of the nozzle is ensured, which contributes to the improvement of the reliability of the excess developer removing device and the drive source. Since it is shared, it can contribute to the cost reduction of the excess developer removing device.

[Brief description of drawings]

FIG. 1 is a configuration diagram for explaining an excess developer removing device according to the present invention.

FIG. 2 is a diagram for explaining the operation of the excess developer removing device according to the present invention.

FIG. 3 is a schematic diagram showing a surplus developer removing device according to the present invention.
7 is a timing chart showing operation timings of main part members.

FIG. 4 is a side view for explaining a conventional excess developer removing device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Excessive developing solution removing device, 2 ... Photosensitive material, 6 ... Rotating drum, 16-19 ... Developing device, 16a-19a ... Developing electrode,
20 ... Blower, 20a ... Nozzle, 30 ... Developing device advancing / retreating means, 36 ... Drive source (motor), 37 ... Rotating shaft, 38 ... Developing device advancing / retreating cam, 39 ... Nozzle advancing / retreating cam, 50 ... Nozzle advancing / retreating means.

Claims (2)

[Claims] 1. A rotatable rotary drum that winds a photosensitive material on which a latent image is recorded and transports the photosensitive material as a unit, and a developing device that is capable of advancing and retracting with respect to the rotary drum and having a developing electrode therein. A developing solution supplied to the developing electrode from the latent image recorded in a state where the developing device is brought close to the rotating drum, and a developing solution is developed into a visible image. In a surplus developer removing device that removes by means of air blown from a nozzle provided downstream of the developing device in the transfer direction of the photosensitive material, the nozzle is brought close to the developing electrode only while developing the photosensitive material. An excess developer removing device, which is provided with a nozzle advancing / retreating means that can freely move back and forth. 2. The excess developer removing device according to claim 1, wherein the nozzle advancing / retreating means uses the same drive source as the developing device advancing / retreating means for advancing / retreating the developing device, and the driving source is used for advancing / retracting the developing device. A surplus developer removing device, wherein a cam and a nozzle advancing / retreating cam are provided in phase with each other.