JP3077235B2 - Image forming device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copying machine, a printer,
The present invention relates to an image forming apparatus that can be used for a plotter, a facsimile, and the like.

[0002]

2. Description of the Related Art Conventionally, an image recording apparatus for controlling the passage of toner particles through an aperture by applying an image signal to an electrode having an aperture to obtain an image on a support has been proposed in US Pat. No. 3,689,935. I have. In this proposal, a reference electrode which is continuous on one surface with an insulator layer interposed therebetween and a plurality of control electrodes which are insulated from each other on the other surface are provided. An aperture electrode body having a row of apertures, means for selectively applying a potential between the control electrode and the reference electrode, and a flow of toner particles through the aperture is modulated by the applied potential. It comprises means for projecting charged particles and means for positioning the support in the particle flow path by the relative movement of the support and the aperture electrode body.

[0003]

However, the electrodes having apertures due to the toner are very dirty and clogged, causing problems in the output image.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an image forming apparatus capable of reducing the dirt and clogging of an electrode having an aperture and obtaining a stable output image. The purpose is.

[0005]

In order to achieve this object, an image forming apparatus according to the present invention controls the passage of charged toner through an aperture by applying an image signal to an electrode having an aperture. In an image forming apparatus for forming an image on a support provided on the opposite side of a toner supply source by a cloud and an apertured electrode, a charging unit for strongly charging toner clogged in the aperture, and an aperture charged by the charging unit And a removing electric field generating means for attracting and removing the toner clogged in the toner.

[0006]

According to the present invention having the above construction, the toner clogged in the aperture is strongly charged by the charging means, and the toner clogged in the aperture charged by the charging means is attracted to the removing electrode to eliminate the clogging of the aperture. I do.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of an image forming apparatus 100 according to an embodiment of the present invention. As shown in detail in FIG. 2, the aperture electrode body 1 has a reference electrode 3 on the toner supply source side of the insulating layer 2 and a control electrode 4 on the support side.
A large number of apertures 6 penetrating through the insulating layer 2 and the control electrode 4 are formed in a line in the width of the support. In FIG. 1, on the left side of the image forming apparatus 100, a cassette 50 for storing the support 10 and a half-moon roller 5 for supplying the support 10 one by one.
1, a support supply roller 52 for feeding the support 10 to a downstream portion, and a chute 53 are provided.

On the downstream side, on the control electrode side of the aperture electrode body 1, the support transport roller 14, the sensor 57, and
A back electrode 11 is provided in contact with the back surface of the support 10, and each control electrode 4 is connected to a control voltage drive circuit 8 that generates a voltage according to an image signal. The back electrode 11 is connected to a negative high voltage power supply 12.

A toner transport belt 26 is wound around the reference electrode side of the aperture electrode body 1 between the drive roller 20 and the backup roller 24.
A cam roller 27 having an elliptical cross section is arranged on the back side of the surface facing the aperture electrode body, and a static elimination brush 31 is arranged on the upstream side. The toner case 21 includes the toner 22 stored in the vicinity of the supply roller 23 and the support roller 30 which is in contact with the supply roller 23 and has a clearance of 0.1 to 0.4 mm with respect to the toner conveyance belt 26.
Is stored within. The supply roller 23 is a sponge,
The carrying roller 30 has a surface formed of resin.

A corotron 61, a removing electrode 62, and an elastic blade 63 are provided on the outer peripheral side of the toner transport belt 26 and downstream of the surface facing the aperture electrode body with respect to the traveling direction of the toner transport belt 26. The corotron 61 and the removal electrode 62 are fixed to the same frame (not shown), and can be simultaneously moved to the left by a driving source (not shown).

Further downstream, the fixing device 13 and the chute 5
4, a discharge roller 55 and a tray 56 are provided.

The operation of the above configuration will be described in detail below.

The support 10 housed in the cassette 50 is
Rolled out one by one by the half moon roller 51, the shoot 5
3 and is transported to the support transport roller 14 by the support supply roller 52. When the sensor 57 detects the leading end of the support 10, the toner transport belt 26 rotates between the backup roller 24 and the drive roller 20 by the rotation of the drive roller 20 in the direction of the arrow, and the toner 22 by the rotation of the supply roller 23 in the direction of the arrow. After being rubbed by the carrying roller 30 and positively charged, the toner is carried on the toner conveying belt 26 by electrostatic application using a high-voltage power supply.

The carried toner is conveyed toward the surface facing the aperture electrode. At the upstream side of this position, the charge of the conveying belt 26 is removed from the back side of the conveying belt 26 by the discharging brush 31. Since the cam roller is rotating at the position facing the aperture electrode, the surface of the transport belt 26 vibrates.
Therefore, the toner carried on the transport belt 26 receives a force due to the vibration acceleration of the transport belt 26, and is released from an adhesive force such as a mirror image force, a Van der Waals force, and an electrostatic force with the transport belt 26.

On the other hand, when a negative voltage is applied to the control electrode 4 according to an image signal from a storage means (not shown) at this time, the applied aperture 6 of the control electrode 4 is directed from the back surface to the front surface of the aperture 6. The positively charged toner 22 having the lines of electric force formed thereon is drawn out from the back surface of the aperture 6 to the front surface, and further fly over the support by the flying electric field formed by the back electrode 11, It is held and forms an image portion. By applying the same potential or a positive voltage as that of the reference electrode 3 to the control electrode 4 of the aperture 6 corresponding to the non-image portion, the flying electric field generated by the back electrode 11 is shielded, or the front face to the back face in the aperture 6 , The passage of the toner 22 through the aperture 6 is suppressed. By repeating this process while transporting the support 10, a toner image is formed on the entire surface of the support 10.

The support on which the toner image is formed is a fixing device 1
3 and the image is fixed on the support 10. Further, the tray 5 is guided by a chute 54,
It is discharged to 6.

Before the process for forming the next toner image, the corotron 61 is driven by the driving source (not shown) to open the aperture 6.
And the state of FIG. 3 is obtained. Here, ions are generated by the corotron 61, and the toner 22 attached to the aperture 6 is positively and strongly charged.

Further, the removal electrode 62 is moved directly below the aperture 6 by a driving source (not shown), and the state shown in FIG. 4 is obtained. Here, by applying a high negative voltage to the removing electrode 62, the toner 22 attached to the aperture 6 is drawn to and attached to the removing electrode 62.

Then, the corotron 61 and the removal electrode 62 are returned to their original positions by a driving source (not shown). At this time, the elastic blade 63 scrapes the toner 22 on the removing electrode 62 and cleans the removing electrode.

Therefore, the toner 22 attached to the aperture 6 is removed before the aperture 22 is clogged with the toner 22, so that a stable toner image is formed.

Further, the present invention can be modified without departing from the spirit of the present invention without being limited to the above-described embodiment.

[0023]

As is clear from the above description,
According to the present invention, it is possible to reduce contamination and clogging of an electrode having an aperture, so that a stable toner image is formed.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an embodiment embodying the present invention.

FIG. 2 is a perspective view showing details of an aperture electrode body.

FIG. 3 is a cross-sectional view of the first embodiment in a first operation state.

FIG. 4 is a cross-sectional view of the second embodiment in a second operation state.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 aperture electrode body 2 insulating layer 3 reference electrode 4 control electrode 6 aperture 8 control voltage drive circuit 10 support 11 back electrode 12 high voltage power supply 22 toner 23 supply roller 26 toner transport belt 27 cam roller 61 corotron 62 removal electrode

Claims (1)

(57) [Claims] An image signal is applied to an electrode provided with an aperture to control the passage of charged toner through an aperture, and a toner supply source by a toner cloud and a support provided on the opposite side of the electrode provided with the aperture. An image forming apparatus for forming an image on the image forming apparatus, comprising: charging means for charging toner clogged in the aperture; and removing electric field generating means for attracting and removing the toner clogged in the aperture charged by the charging means. A characteristic image forming apparatus.