JPS63132271A - Electrostatic recorder - Google Patents

Abstract

PURPOSE:To prevent the occurrence of interference caused by air containing ozones and toner does to image formation by permitting a wind direction regulating means provided in the interior of an electrostatic charger to regulate the direction and establishing the flowing path of the wind blown toward a suction port provided in a cleaning device. CONSTITUTION:The electrifying device 60 is provided with an electrode 64 consisting of a pair of stretched wires, a back plate 61 made of a metallic member, an oblong opening part 611 provided on the back of the back plate, a duct 531 from a cross flow fan installed on the back of the electrifying device to the opening part 611 and the wind direction regulating plate 65 made of a rigid thin sheet between the opening part of the back plate and the electrode. The cleaning device 20 is equipped with a main duct 50, a lower duct 51, a suction area 52, a 1st suction port 264 and a 2nd suction port as the suction means sucking toner from the suction port. Thus the flow of the air which is blown from the opening part 611, sucked from the upper suction port 521 and jointed in a suction area 52 cleans the ozone at the electrifying device 60 and toner stuck to an electrode wire.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to an electrostatic recording device such as an electrophotographic copying machine, and more particularly to an electrostatic recording device in which air blown from a charging device is sucked by a cleaning device.

[Conventional technology]

Generally, electrostatic recording devices such as transfer-type electrophotographic copying machines use a rotating drum-type image carrier having a photoconductive photosensitive layer on its outer circumferential surface, and the image carrier is charged by a charging device while rotating. An electrostatic latent image is formed on the photosensitive layer, developed with toner, and the resulting toner image is transferred to recording paper. After the transfer is completed, the residual toner adhered to the outer peripheral surface of the image carrier is removed and cleaned by a cleaning device, and an electrostatic latent image is formed again, and a new image is transferred. It is well known that when a high voltage is applied to the electrodes of the charging device to apply a charge to the bad light layer of the image carrier, a large amount of ozone is generated due to corona discharge. As the concentration of ozone in the charging device increases as copying continues, oxides tend to adhere to the electrodes and also have a negative effect on charging efficiency, resulting in uneven charging of the image carrier.
This will cause density unevenness in the formed image. In order to eliminate this accumulation of ozone in the charging device, a long slit-like hole is made in the back of the back plate that shields the electrode, and a fan blows outside air through the long hole to dilute the ozone concentration around the electrode. After that, a means is taken to discharge it to the outside of the charging device. On the other hand, in a cleaning device, a method is used in which the L/ner scattered inside and outside the device is sucked by suction means. This is, for example, a method in which the l/ner mixed in from the cleaning device and attached to the image carrier is sucked out from a suction port provided at an appropriate location of the cleaning device facing the image carrier, or This method involves sucking up toner floating inside the cleaning device through a suction port provided in a frame inside the device.

[Problems to be solved by the invention]

Toner powder and paper powder may adhere to the electrodes of the charging device and the inner surface of the backbrake I, and in the method described above in which ozone is emitted without changing the direction, these adherents may be attached to the image carrier. There is a risk that it will scatter and adhere to the downstream side, that is, a new image forming/processing section, which is undesirable. The present invention has been made in view of the above-mentioned drawbacks of the prior art, and is configured so that ozone, toner, etc. generated in the charging device are discharged only in the upstream direction of the image bearing member together with the outside air, while cleaning On the device side, an electrostatic recording device is provided with a suction port provided facing the image carrier near the charging device to suck air containing ozone, toner, etc. released from the charging device, thereby eliminating adverse effects on others. The purpose is to provide

[Means to solve the problem]

The above object is to provide an electrostatic recording device that includes a cleaning device that faces an image carrier and removes residual toner, and a charging device that charges the image carrier downstream of the cleaning device. A wind direction regulating means is provided in the cleaning device, and a suction suction port is provided in the cleaning device, and the air blown to the charging device is directionally regulated by the wind direction regulating device toward the cleaning device and is sucked through the suction suction port. This is achieved by an electrostatic recording device characterized by the following.

【Example】

Embodiments of the electrostatic recording device according to the present invention will be described below with reference to FIGS. 1 to 8, but the embodiments of the present invention are not limited thereto. First, the charging device in the electrostatic recording device will be cleaned. Each process leading up to the device will be briefly explained. The image carrier 10 is a drum-shaped photoreceptor in which a photoconductive material is laminated to a certain thickness on a conductive metal substrate, and is configured to be rotatable, and rotates in the direction shown by the arrow to cover its photoconductive surface. passes sequentially through a plurality of processing stations (not shown). The peripheral surface of the image carrier 10 is irradiated with a pre-charging exposure light source 62 to remove residual charges, and then charged by the charging device 60 according to the present invention, so that the surface of the image carrier 10 is uniformly charged. Hold. The image carrier 10, whose photoconductive surface is uniformly charged, rotates in the direction of the arrow and enters an exposure section (not shown). In the exposure section, reflected light from the original is irradiated onto the photoconductive surface of the image carrier 10 through an optical system such as a mirror and lens, thereby discharging the charges in the exposed area and creating an electrostatic latent image of the original in that area. The image carrier 10 on which the electrostatic latent image has been formed enters a developing section (not shown) as it rotates in the direction of the arrow. In the developing section, the electrostatic latent image is developed by a developing device, and a developing material containing charged toner particles adheres to the latent image to visualize it into the original shape of the document. The one-image carrier 10 carrying the toner image visualized by the toner further rotates and enters a transfer section (not shown). In the transfer section, a recording sheet is conveyed in synchronization with the toner image, and the toner image is transferred onto the recording sheet. The recording sheet onto which the toner image has been transferred is separated from the image carrier 10 by a separator as a transfer sheet, further fixed by a fixing device, and then discharged outside the apparatus. On the other hand, the image carrier 1° separated from the recording paper by the separator enters the cleaning device 2o shown in cross section in FIG. is removed. The cleaning device includes a cleaning blade 21 that actively presses against the image carrier to scrape off residual toner, a fur brush 22 that actively rubs the image carrier to scrape off the residual toner, and the fur brush. 22, an elastic roller that is rotatably arranged and presses against the image carrier, and a static elimination electrode that eliminates the charge of the residual toner below the elastic roller. After the transfer process is completed, the untransferred toner adhering to the outer circumferential surface of the image carrier 10 is removed as the image carrier 10 rotates in the direction of the arrow and its tip reaches a position opposite the static elimination electrode 27. , the charged state of the residual toner is removed by the action of the static eliminating electrode 27. Then, it passes through an elastic roller 23 that is lightly pressed against the image carrier 10 and reaches a position opposite the fur brush 22 . The fur brush 22 is in pressure contact with the image carrier 10 with a nip width of 3 to 4 mm, and rotates in the opposite direction to the image carrier to rub and remove residual toner on the image carrier.
Remove. Approximately 20% to 40% of the residual toner on the image carrier is rubbed off by the fur brush 22. However, the residual toner that could not be removed by the fur brush 22 is sufficiently loosened from adhering to the image carrier by the rubbing action of the fur brush 22, and is then scraped off by the cleaning blade 21. The residual toner rubbed and removed from the image carrier by the fur brush 22 is transferred to the bristles 29 of the fur brush 22, and as the fur brush 22 rotates, the toner is rubbed and removed from the image carrier, and as the fur brush 22 rotates, the toner is rubbed and removed from the image carrier. It is conveyed to the position of a flicker 30 installed so as to uniformly strike the bristles 29, is knocked off by the flicker 30, and falls onto the pressure feeding screw 34. The residual toner scraped off by the cleaning blade 21 falls along the circumferential surface of the image carrier and reaches the fur brush 22 . Since the fur brush 22 is rotating in the opposite direction to the rotation direction of the image carrier as described above, some of the toner that has fallen from the cleaning blade 2 is collected by the bristles 29 of the fur brush 22 and transported. The remaining toner is knocked off by the flicker 30, but the remaining toner falls from the part where the image carrier and the fur brush 22 are separated and reaches the elastic roller 23. are in a press-contact state (7) and the elastic roller 23 rotates as a result of the image carrier 10, so the falling toner does not reach any further downward and is conveyed according to the rotation of the elastic roller 23. and the thickness is about 1
It is made of 0.00 micron Mylar and has a length substantially corresponding to the width of the elastic roller 23, and its free ends are in pressure contact with the entire length of the elastic roller 23, and the other end is in contact with the frame of the cleaning device. A scraper holder 3 is installed between the side plates of the body so as to be rotatable with the longitudinal direction as the axis of rotation.
3 is scraped off by a scraper 32 fixed to the screw 34, and reaches the pressure feeding screw 34. 1 to 3 are diagrams showing the vicinity of a charging device and a cleaning device of an electrostatic recording apparatus according to the present invention. The charging device 60 corresponds to a blower means for blowing out air, and the cleaning device 20 corresponds to a suction means for sucking air. The charging device 60 includes an electrode 111i64 made of a pair of stretched wires A, and a back plate 61 made of a metal member having a substantially U-shaped cross section with an open surface of the electrode 64 facing the image carrier 10. , an elongated opening 611 provided on the back of the back plate, and a cross flow fan (not shown) provided on the back of the charging device.
1 to 1, and a wind direction regulating plate 6 made of a rigid thin plate between the opening of the back plate and the electrode.
It is constructed as a charging device in which a blower means is arranged inwardly. An electric suction fan (not shown) or the like is installed in the electrostatic recording device, and suction means for sucking toner from a suction port disposed at an appropriate position in the cleaning device includes a main duct 5o, a lower duct 51, and a suction device. Area 52 and
It is composed of a first suction hole 264 and a second suction hole 265. The main duct 50 is disposed on the back side of the cleaning device, and collects all the air mixed with toner from the suction ports arranged at appropriate positions of the cleaning device, and is used for electric suction (not shown) inside the electrostatic recording device. This is a conduit that conveys to the fan section. The lower duct 51 is provided near the bottom of the cleaning device, and includes an upper duct plate 1-263, a lower duct plate 262, a right side plate 24 that is both sides of the cleaning device frame, and a left side plate. 25 and has a cross-sectional shape as shown in the drawing, which has a width substantially equal to the width of the image carrier, and is located below the elastic roller 23 and close to and opposite to the surface of the image carrier. A lower suction port 5]1 is provided. The suction area 52 has a top surface play 1-266;
a back plate 260, a middle partition wall 267 and a first Mylar plate 268 fixed near both ends of the middle partition wall;
The second mylar plate 269 forms one hollow part, and the upper surface of the free end side of the cleaning blade 21 and the upper surface plate 266 form an upper suction port 521.
is formed. The upper suction port 521 is connected to the image carrier 1.
0 surface, and are open to each other along the entire length in the longitudinal direction. Furthermore, two openings, a first suction hole 264 and a second suction hole 265, are provided in the rear plate 260 of the suction area 52 at opposing positions near both ends of the image carrier. A suction opening for sucking the air inside 52 is formed. The blower means 53 forms a flow path from the opening 611, through the wind direction regulating plate, between the notch 621 of the light source 62 and the surface of the image carrier, and reaching the upper suction port 521. The blower means of the charging device and the suction means of the cleaning device of the electrostatic recording apparatus according to the present invention have the above-mentioned configurations, and their functions will be explained below. After confirming that the cleaning blade 21 is pressed against the image carrier, an electric suction fan and an electric blow-off fan (not shown) in the copying apparatus start operating in response to a copy start signal. An air flow path is formed by the operation of each of these fans. The flow path is a flow path for air blown from the cross flow fan (not shown) of the blower means 53, which passes through the duct 1-531 and flows into the back plate 61 from the opening 611, and The wind direction regulating plate 65 has an inclination such that the upstream side in the rotation direction of the image carrier is diagonally upward and the downstream side is also downward. This is a flow path that passes through the upper suction port 521 to the suction area 52, is sucked by the first suction hole 264 and the second suction hole 265 of the area 52, and reaches the main duct 50. Then, the lower duct 5 is sucked from the lower suction port 511.
This is the flow path that passes through the main duct I/50. On the other hand, it is a flow path that is sucked from near both ends of the image carrier in the suction area by the first suction port 264 and the second suction hole 265 and reaches the main duct 50. The flow of air blown from the opening 611 of the charging back plate 1/61 of the charging device 60, sucked from the upper suction port 521, and following the flow path converging at the suction area 52 is caused by the ozone and It has a cleaning effect on l, toner, etc. that adheres to the electrode wire, and also removes toner that leaks out near the upper suction port 521.
The blowing effect of the previous blowout and the effect of suction combine to produce a rubbing and removal effect of the air against the surface of the image carrier. The cleaning device is divided into two hollow parts by the intermediate partition wall 267 and a first Mylar plate 1-268 and a second Mylar plate 269 fixed thereto, the upper part of which is the suction area. 52, and the lower part is the cleaning area 54.
It is. A fur brush 2 is provided in the cleaning area 54.
2, flicker 30, elastic roller 23 and scraper 32
, a pressure feeding screw 34, etc. are installed, and during the cleaning operation, some of the toner scraped off by the cleaning blade 21 or the toner knocked off from the fur brush 22 by the flicker 30 enters the cleaning area 54. It is scattered and is in a state of being cloudy. The suction means in the cleaning device is constructed so that the cleaning area 54 is surrounded by an upper suction port 521 and a lower suction port 511 of the suction area 52, and the toner leaking from the cleaning area 54 is immediately sucked and scattered. The structure is designed to prevent harmful effects caused by energy to others. FIG. 5 is a side sectional view of the cleaning device showing a mechanism for pressing and releasing the cleaning blade 21 against the image carrier 10. The pressure contact/release mechanism includes a DC motor 43 fixedly supported at three points above the right side plate 24 facing the image carrier 10, and a drive gear G1 fixedly fixed to the main shaft of the DC motor 43. An intermediate gear G2 that meshes with the drive gear G1, and a cam 4 that shares the rotating shaft to which the intermediate gear G2 is fixed and is also fixed to the rotating shaft.
4, a stay 42 that engages the cam surface of the cam 44 with an engaging portion 421, a blade shaft 41 to which the stay 42 is fixed to the shaft end, and a blade shaft 41 that swings by rotation of the blade shaft 41. Blade holder 28 and the blade holder 2
8 to the image carrier 10 at all times. The DC motor 43 is a geared motor that outputs the rotational speed of its output shaft in a pre-adjusted state through a plurality of gears in the housing of the motor. The drive gear G1 is fixed. The intermediate gear G2 that meshes with the drive gear G1 is made of synthetic resin, has a bearing part on the right side plate 24, and is fixed together with the cam 44 to a rotating shaft 45 that is rotatably supported by the bearing part. The rotational force from drive gear G1 is transmitted to both intermediate gear G2 and cam 44. The stay 42 has a side engaging portion 421 at one end that is engaged with the cam surface of the cam 44, and the other end is fixed to the blade shaft so that the stay 42 engages with the cam surface of the cam 44 as the cam 44 rotates. The grasping motion of the stay engaging portion 421 is transmitted to the rotation of the blade shaft, and is converted into an operation of pressing the cleaning blade 21 against the image carrier 10 and releasing it. Incidentally, the load when the cleaning blade 21 is pressed against the image carrier is a value determined by the pressure contact springs 46 and 47, and the actual value in the example is 30 g/cm to 5 JH.
/cm. The mechanism for pressing and releasing the cleaning blade 21 against the image carrier 10 is constructed as described above, and its operation will be described below. In response to the copy start signal, the DC motor 43 rotates for a predetermined time, and the drive gear G1 fixed to the output shaft of the DC motor 43 rotates the cam 44 together with the intermediate gear G2, so that the engagement portion 421 of the stay 42 The cam surface of the cam moves upward due to the biasing force of the pressure springs 46 and 47, rotates the blade shaft 41, and thus the cleaning blade 21
is brought into pressure contact with the image carrier 10. During copying, the cleaning blade 21 continues to be in the pressure contact state and continues to scrape off residual l/toner on the image carrier. In response to the copy end signal, a timer (not shown) activated by the signal causes the DC motor 43 to start rotating after about one minute, and the cam 44 presses the engaging portion 421 of the stay 42 between the springs 46 and 47. The cleaning blade 21 is pushed down against the urging force, and the cleaning blade 21 is thus separated from the surface of the image carrier. Due to the operation of the above-mentioned pressure contact/release mechanism, the pressure contact of the cleaning blade 21 against the image carrier can be kept to the necessary minimum, so that the image carrier 21 that is caused by the cleaning blade being constantly in pressure contact with the image carrier can be reduced. It is possible to reduce scratches and dents on the body, and these lagoons,
Copy defects caused by dents or the like can be prevented from occurring, and at the same time, the life of the image carrier can be extended. In addition, by providing a mechanism for pressing and releasing the cleaning blade against the image carrier on the cleaning device side,
Compared to the conventional method in which the driving force is received from outside the device via a transmission means, the intermediate mJ transmission member or the same means has a simple structure. This method, which eliminates the need for a driving force transmission means from outside the cleaning device, not only makes it easier to install and remove the device during cleaning and maintenance, but also eliminates the need for conventional driving force transmission. Problems caused by cumulative variations in processing accuracy of each member can be eliminated. The sequence of the blowing action of the charging device and the suction action of the cleaning device in the electrostatic recording apparatus of the present invention as described above will be explained using the time chart of FIG. 6. First, when the copy button is turned on, the Prior to the operation of the fan (electric suction fan), ■Blow fan (cross flow fan), etc. ■The blade pressure contact/release motor is turned on and the DC motor 4
3 starts and the image carrier of the cleaning blade 21]
Start pressing operation against 0. After a predetermined period of time has elapsed from the start of the pressing operation of the cleaning blade 21, the pressing operation is completed, and then the operation of (1) the main motor, (2) the suction fan, and (3) the blow fan are simultaneously started. This is because the cleaning blade 21 is attached to the image carrier 1.
In addition to the reason that the residual toner cannot be cleaned by the cleaning blade 21 unless pressure contact with the image bearing member 21 is completed, if there is a gap between the image bearing member and the cleaning blade, the residual toner is removed from the gap. This is inevitable because the air blown out from the blower means 53 enters the cleaning area 54 and causes a large amount of toner to leak out from the cleaning area, which is filled with toner. In this way, the image carrier 10 of the cleaning blade 21
When the pressure contact is completed, the main motor, suction fan, and blow fan start operating at the same time, and copying is performed. At the end of the first copy process, when the number of copied recording sheets reaches a desired number and a copy end signal is issued, the main motor, suction fan, and blow fan simultaneously stop operating. After a period of time has elapsed until the effects of the suction fan and blow fan subside, the blade pressure release motor starts, and the DC motor 43 rotates to separate the cleaning blade 21 from the image carrier 10, thereby releasing the pressure contact. . This is also for the same reason as described above, and is strictly controlled so that the cleaning area is kept in a sealed state by pressure contact between the blade and the image carrier, and air is not blown into the cleaning area by the blow fan. FIG. 7 shows a flowchart 1 to 1 at the start of copying regarding the operation of the blower means of the charging device and the suction means of the cleaning device in the electrostatic recording apparatus of the present invention. When the copy button is turned on, the LED
The ON status is indicated by lighting up. If it is OFF, operate the copy button ○N again. By turning on the copy button, the cleaning blade 2
The pressure contact/release DC motor 43 starts and rotates in a direction to bring the cleaning blade 21 into pressure contact with the image carrier 10 . After waiting for one second, which is required for the cleaning blade 21 to complete the reliable pressure contact with the image carrier 10, the main motor, suction fan, and blow fan operate simultaneously to start copying. FIG. 8 shows the flowchart 1 at the end of copying for the blower means of the charging device and the suction means of the cleaning device (electrically operated) of the present invention. A copy end signal is issued when the paper is ejected, etc. When the copy is completed, the main motor, suction fan,
The operation of the blow fan is stopped at the same time. After that, the DC motor 43 for pressing and releasing the cleaning blade 21 rotates in the direction of releasing the cleaning blade 21 after waiting for the elapse of 2 seconds, which is the time required for the air flow by the suction fan or the blow fan to stop. The blade is separated from the image carrier and continues in this state. [Effects of the Invention] As is clear from the above description, the direction of the air is regulated by the airflow direction regulating means provided in the charging device of the electrostatic recording device of the present invention, and the air flow path reaches the suction suction port provided on the cleaning device. As a result, it is possible to prevent air mixed with ozone, toner, etc. from interfering with new image formation, and to keep the inside of the charging device and the opposing part of the image carrier clean. As a result, an electrostatic recording device capable of producing accurate copies with good image quality has been provided.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the suction means of the cleaning device and the blowing means of the charging device in the electrostatic recording device of the present invention, and FIG. 2 shows the frame of the cleaning device on the side of the image carrier. FIG. 3 is a perspective view showing the suction duct, FIG. 4 is a sectional view of the cleaning device, and FIG. 5 is a perspective view showing the suction duct.
6 is a side cross-sectional view showing a cleaning blade pressure release mechanism, FIG. 6 is a time chart 1-1 of the blower means of the charging device and the suction means of the cleaning device in the electrostatic recording device of the present invention, and FIG. 8 is a flowchart of the blowing means of the charging device and the suction means of the cleaning device when copying is started, and FIG. 1o... Image carrier 20... Cleaning device 21... Cleaning blade 22... Fur brush 23... Elastic roller 24
...Right side plate 25...Left side plate 26...
Frame body 27... Static elimination electrode 28... Two blade holders... Hair body 264... First suction port
265...Second suction port 266...Top surface play i-2
67... Yoko Hibama 268... 1st Miler Play 1
・ 269...Second mylar plate 30...Flicker 32...Scraper 33...
Scraper holder 34...Pressure screw 40...Inner unit 41
...Blade shaft 42...Stay 43...DC
Motor 44...Cam 45...Rotating shaft
46, 4.7・Pressure spring 421...Engagement part
50... Main duct 51... Lower duct 52... Suction area 53... Blower means 54
...Cleaning area 511...Lower suction port 521...Upper suction port 531r...Dak 1 to 60...Charging device 61...Back plate 62...Light source 64/electrode 65...Wind direction regulation Plate 611... Opening 621... Notch Gl, G2. ...
Gear applicant Konishiroku Photo Industry Co., Ltd. Figure 7 Figure 8

Claims (1)

[Claims] An electrostatic recording device including a cleaning device that removes residual toner facing an image carrier, and a charging device that charges the image carrier downstream of the cleaning device, wherein a wind direction regulating means is provided in the charging device. and the cleaning device is provided with a suction suction port, and the air blown to the charging device is directionally regulated toward the cleaning device side by the air direction regulating means so as to be sucked through the suction suction port. electrostatic recording device.