JPH06297752A - Image forming apparatus - Google Patents

Abstract

PURPOSE:To provide an image forming apparatus not generating the lowering of image quality due to clogging, capable of supplying a large quatity of toner to a toner flow control means to increase recording density and capable of forming an image of high quality. CONSTITUTION:A large number of grooves 2a extending toward one end of an insulating sheet 2 from apertures 6 are formed to the surface on the side of a toner support roller of the insulating sheet 2 corresponding to the respective apertures 6 and the extending direction of the grooves 2a coincides with the rotary direction of the toner support roller 14. Therefore, it is prevented that the toner held on the toner suapport roller 14 at the parts corresponding to the apertures 6 is further made thin by the grooves 2a of the insulating sheet 2 and a large quantity of the toner is supplied to the apertures 6 through the grooves 2a and an image with high recording density can be formed on a support.

Description

Detailed Description of the Invention

[0001]

BACKGROUND 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 plotters, facsimiles, and the like.

[0002]

2. Description of the Related Art Conventionally, an image forming apparatus for obtaining an image on a support by controlling the passage of toner particles through an aperture by applying an image signal to an electrode having an aperture has been proposed in US Pat. No. 3,689,935. Has been done.

The image forming apparatus described in US Pat. No. 3,689,935 is composed of a shield electrode which is continuous on one side with a layer of an insulator interposed therebetween and a plurality of control electrodes which are insulated from each other on the other side. And is formed through three layers for each insulated plurality of control electrodes and at least 1
An aperture electrode body having apertures arranged in rows, a means for selectively applying a potential between the control electrode and the shield electrode, a means for supplying charged toner particles to the aperture of the aperture electrode body, and a support It is arranged on the opposite side of the aperture electrode body, and comprises a back electrode to which a high voltage is applied, and a means for moving the support body relative to the aperture electrode body to position the support body in the particle flow path. Has been done.

However, according to this apparatus, the toner particles clog the apertures to deteriorate the recording quality, and the recording speed cannot be increased so much.

The applicant of the present invention further studied,
As already filed in the application No. 254494, there is also proposed an image recording apparatus capable of greatly improving recording characteristics by disposing a carrier holding toner and a recording electrode in contact with each other. According to this device,
Since the recording electrodes are not clogged, the image quality is remarkably improved, and it has become possible to reduce the size and cost of the image recording apparatus.

[0006]

However, in this conventional image forming apparatus, since the carrier holding the toner and the recording electrode are arranged in contact with each other, the amount of toner supplied to the recording electrode is small. There was a problem that the recording density was low and the recording density was low.

The present invention has been made in order to solve the above-mentioned problems, and there is no deterioration in image quality due to clogging, and moreover, a large amount of toner can be supplied to the toner flow control means and recording density can be improved. It is also an object of the present invention to provide an image forming apparatus capable of forming a high quality image by making it darker.

[0008]

In order to achieve this object, an image forming apparatus of the present invention comprises a toner flow control means provided with a toner flow control section, and a toner for supplying a charged toner to the toner flow control means. The carrier and the toner carrier are composed of a back electrode provided on the opposite side with the toner flow control means interposed therebetween, and control the passage of the toner supplied by the toner carrier through the toner flow control unit to control the back surface. An image forming apparatus for forming an image on a support supported on an electrode, wherein the toner carrier is disposed in contact with the toner flow control means at a toner flow control portion, and the toner flow control means is provided. A groove extending in the moving direction of the carrier through the toner flow controller is formed on the surface of the toner carrier side.

Further, a toner flow control unit having a toner flow control unit, a toner carrier for supplying the toner charged to the toner flow control unit, and the toner carrier are opposite to each other with the toner flow control unit interposed therebetween. An image forming apparatus configured to form an image on a support supported on the back electrode by controlling passage of toner supplied from a toner carrier through a toner flow control unit, the back electrode being provided on the back electrode. Thus, a groove extending in the moving direction of the toner carrier is formed in a portion of the toner carrier facing the toner flow controller.

[0010]

According to the image forming apparatus of the present invention having the above structure, a large amount of toner is generated through the groove extending in the moving direction of the carrier as the toner flow control means and the toner carrier move relative to each other. -Supplied to the toner flow controller. The toner that has passed through the toner flow control unit flies toward the back electrode and then deposits on the support, forming a high-density image on the support.

[0011]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing an outline of an image forming apparatus according to the present invention, in which a columnar cylinder serving as a back electrode having a gap of 1 mm on the upper side of an aperture electrode body 1 serving as a toner flow control means. The rear electrode roller 22 is a body (not shown)
It is rotatably disposed in the space and is configured to be able to convey the support body 20 inserted into the gap.

Below the aperture electrode body 1, along the longitudinal direction of the aperture electrode body 1, the toner supply device 1 is provided.
0 is disposed, and a transport roller 29 for transporting the support 20 between the aperture electrode body 1 and the back electrode roller 22 is rotatably arranged on the carry-in side of the aperture electrode body 1. Further, the fixing device 26 is installed at the destination of the support 20 conveyed by the back electrode roller 22.
Is provided.

Next, the respective components will be described in detail. In the toner supply device 10, the toner case 11 also serving as a housing of the entire device, the toner 16 housed in the toner case 11, and the supply roller 12 are provided. And a toner carrying roller 14 as a toner carrying member and a toner layer regulating blade 18. Here, the toner carrying roller 14 carries the toner 16 in layers.
The feeding roller 12 feeds the toner 16 to the toner carrying roller 14.

The supply roller 12 and the toner carrying roller 14 are rotatably supported in the toner case 11 in the direction of the arrow shown in FIG. Further, the toner layer regulating blade 18
Is for adjusting the amount of the toner 16 carried on the toner carrying roller 14 to be uniform on the roller surface and for uniformly charging the toner 16, and is pressed against the toner carrying roller 14.

As shown in FIG. 2, the aperture electrode body 1 includes a polyimide insulating sheet 2 having a thickness of 25 μm, and a plurality of apertures 6 having a diameter of 100 μm penetrating the insulating sheet 2 arranged in a line at equal intervals. A control electrode 4 as a toner flow control unit is formed with a thickness of 1 μm at the periphery of the opening of each aperture 6 on the upper surface side of the insulating sheet 2 while being arranged. As shown in FIG. 1, the aperture electrode body 1 is disposed so as to come into contact with the toner on the toner carrying roller 14 at the aperture position of the insulating sheet 2 with the control electrode 4 facing the support body 20. There is.

Toner carrying roller 14 of the insulating sheet 2
A plurality of grooves 2a extending from the aperture 6 toward one end of the insulating sheet 2 are formed on the side surface so as to correspond to the respective apertures 6, and the extending direction of the grooves 2a is arranged so as to be in contact with the toner carrying roller 14. In this state, it coincides with the rotation direction of the toner carrying roller 14. Further, the aperture electrode body 1 is attached so that the groove 2 a is located on the upstream side in the rotation direction of the toner carrying roller 14.

A control voltage application circuit 8 is connected between the control electrode 4 and the toner carrying roller 14.
The control voltage application circuit 8 is configured to apply a voltage of 0 V or +50 V to the control electrode 4 based on the image signal.

Further, a DC power source 24 is connected between the back electrode roller 22 and the toner carrying roller 14, and this DC power source can apply a voltage of +1 kV to the back electrode roller 22. It is like this.

Next, the operation of the image forming apparatus configured as described above will be described.

First, the toner 16 sent from the supply roller 12 is rubbed against the toner support roller 14 by the rotation of the toner support roller 14 and the supply roller 12 in the direction of the arrow shown in FIG. The toner is carried on the toner carrying roller 14. The carried toner 16 is thinned by the layer regulating blade 18 and further charged, and then is conveyed toward the aperture electrode body 1 by the rotation of the toner carrying roller 14. And
The toner on the toner carrying roller 14 is the same as the aperture electrode body 1.
It is supplied under the aperture 6 while being rubbed by the insulating sheet 2.

At this time, in the present embodiment, the toner 16 carried on the portion corresponding to the aperture 6 among the toners on the toner carrying roller 14 is further thinned by the insulating sheet 2 by the groove 2a. Therefore, the aperture 6 has no groove 2 as the toner carrying roller 14 rotates.
A large amount of toner is supplied via a.

On the other hand, the supporting body 20 is conveyed by the conveying roller 29 between the aperture electrode body 1 and the back electrode roller 22.

Here, in accordance with the image signal, the control voltage applying circuit 8 adds + to the control electrode 4 corresponding to the image portion.
A voltage of 50V is applied. As a result, an electric force line from the control electrode 4 toward the toner carrying roller 14 is formed in the vicinity of the aperture 6 corresponding to the image portion due to the potential difference between the control electrode 4 and the toner carrying roller 14. As a result, the negatively charged toner is subjected to an electrostatic force in the direction of higher potential, and the toner from the toner carrying roller 14 is moved to the aperture 6 side.
And is drawn to the control electrode 4 side. The extracted toner 16 further flies toward the support 20 due to the electric field formed between the support 20 and the aperture electrode body 1 by the voltage applied to the back electrode 22, and the toner 16 on the support 20 rises. To form pixels.

At this time, in the present embodiment, the aperture 6
In the groove 2a as the toner carrying roller 14 rotates.
Since a large amount of toner is supplied via the, it is possible to form a high-density image.

A voltage of 0V is applied from the control voltage application circuit 8 to the control electrode 4 corresponding to the non-image portion.
As a result, between the toner carrying roller 14 and the control electrode 4,
Since the electric field is not formed, the toner carrying roller 14
The upper toner 16 does not pass through the aperture 6 because it is not subjected to electrostatic force.

Further, the support 20 is fed by one pixel in the direction perpendicular to the aperture row while the toner 16 forms one row of pixels on the surface thereof. Then, the toner image is formed on the entire surface of the support 20 by repeating the above process. Then, the formed toner image is fixed on the support 20 by the fixing device 26.

The present invention is not limited to the embodiments described in detail above, and various modifications can be made without departing from the spirit of the invention.

For example, in the above embodiment, the control voltage of the aperture corresponding to the non-image portion is set to 0V, but this may be a negative voltage. In this case, an image with less fogging can be obtained.

Further, in the above embodiment, the groove 2a is formed from the aperture 6 of the insulating sheet 2 toward one end and is located only on the upstream side in the rotation direction of the toner carrying roller 14.
A groove extending from one end to the other end of the insulating sheet 2 through the aperture may be formed so as to be positioned on the upstream side and the downstream side in the rotation direction of the toner carrying roller 14 with the aperture interposed therebetween. As shown, the entire insulating sheet 2 may be curved to form the groove 2a.

Further, as shown in FIG. 4, the aperture 6 of the aperture electrode body 31 is provided on the outer periphery of the toner carrying roller 34.
Even if the groove 34a extending in the rotation direction of the toner carrying roller 34 is formed in the portion facing the above, the same effect as that of the above-described embodiment can be expected. In this case, the surface of the insulating electrode 32 of the aperture electrode body 31 on the side of the toner carrying roller 34 may be formed flat as shown in FIG. 4, or the groove 2a shown in FIG. 2 may be formed. May be.

[0032]

As is apparent from the above description, according to the image forming apparatus of the present invention, there is no deterioration in image quality due to clogging, and moreover, there is a relative movement between the toner flow control means and the toner carrier. Therefore, a large amount of toner is supplied to the toner flow controller through the groove extending in the moving direction of the carrier,
A high-density image can be formed on the support, and thus a high-quality image can be formed.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment embodying the configuration of an image forming apparatus of the present invention.

FIG. 2 is a perspective view showing a configuration of an aperture electrode body used in the image forming apparatus of the present invention.

FIG. 3 is a sectional view showing another embodiment of the aperture electrode body.

FIG. 4 is a diagram showing another embodiment.

[Explanation of symbols]

 1 Aperture Electrode Body 2 Insulating Sheet 2a Groove 4 Control Electrode 6 Aperture 14 Toner Carrier Roller 22 Rear Electrode Roller

Claims (3)

[Claims] 1. A toner flow control unit having a toner flow control unit, a toner carrier for supplying the toner charged to the toner flow control unit, and the toner carrier on the opposite side of the toner flow control unit. It consists of a back electrode provided in
An image forming apparatus that controls passage of toner supplied by a toner carrier through a toner flow control unit to form an image on a support supported on a back electrode, wherein The carrier is arranged in contact with the toner flow control section, and a groove extending in the moving direction of the carrier through the toner flow control unit is formed on the surface of the toner flow control means on the toner carrier side. Image forming apparatus. 2. A toner flow control unit having a toner flow control unit, a toner carrier for supplying the charged toner to the toner flow control unit, and the toner carrier on the opposite side of the toner flow control unit. It consists of a back electrode provided in
An image forming apparatus for controlling the passage of toner supplied by a toner carrier through a toner flow controller to form an image on a support supported on a back electrode, wherein the toner flow controller for the toner carrier is In the facing part,
An image forming apparatus, wherein a groove extending in a moving direction of a toner carrier is formed. 3. The toner carrier according to claim 1, wherein the toner carrier carries toner in a layered form.
The image forming apparatus according to item 1.