JP2887514B2 - Image recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention forms a latent electrostatic image by supplying a controlled ion current to a charged latent electrostatic image carrier. The present invention relates to an image recording device that develops an image and records the image.

[Conventional technology]

2. Description of the Related Art Conventionally, as shown in FIG. 5, for example, an image recording apparatus used in a copying machine or the like comprises a dielectric drum 1 which forms an electrostatic latent image carrier and rotates in the direction of arrow C, and A scorotron 2 serving as a charging means which is provided around the periphery and uniformly charges the surface thereof; an ion flow recording head 3 serving as an ion flow recording means for supplying ions to the dielectric drum 1 to form a latent image; A developing device 4 for developing the latent image with toner to form a toner image, a transfer device 5 for transferring the developed toner image to recording paper 6 conveyed at a predetermined timing, and holding the toner A static eliminator 7 that applies an electric charge of the opposite polarity to the electric charge to weaken the electrostatic force of the toner.
And a cleaning device 8 for removing the toner remaining on the dielectric drum 1 after transferring the toner image to the recording paper 6.

An ion flow recording head 3 for forming a latent image on such a dielectric drum 1 is disclosed, for example, in Japanese Patent Laid-Open No. 59-190854.
As shown in FIG. 6, generally, as shown in FIG. 6, a discharge wire 3a that is connected to a discharge power supply (not shown) to generate ions, a discharge wire 3a that surrounds the discharge wire 3a, and A shield 3b forming a transfer fluid passage P through which a transfer fluid such as pressurized air for transferring generated ions flows; and a shield 3b disposed at an outlet Pa of the transfer fluid passage P to form a predetermined electric field at the outlet Pa. And a control electrode 3c for controlling the outflow of the ion, the main part of which is formed. The ions generated by the discharge wire 3a are placed on the transfer fluid, and the outflow direction of the ion flow from the outlet Pa as the ion flow is the scorotron 2 It is arranged toward the side.

By the way, in such an image recording apparatus, an image is recorded on the recording paper 6, and a charge having a polarity opposite to that of the toner is given to the remaining toner by the charge eliminator 7 to weaken the electrostatic force (the charge is removed), and The residual toner is removed by the cleaning device 8, and the residual toner is removed from the surface of the dielectric drum 1 as much as possible before reaching a position of the scorotron 2 again.

However, the transfer and cleaning may be insufficient due to the environment, especially fluctuations in humidity, and the potential of the residual toner may not be completely ± 0 V even after being subjected to static elimination. In this case. Therefore, when the residual toner is blown out from the outlet Pa of the ion flow recording head 3 toward the scorotron 2 near the scorotron 2, the residual toner is sowed up by the ion flow. Toner on discharge wire 2a or grid 2b, etc. (especially toner having a potential opposite in polarity to the potential of discharge wire 2a or grid 2b)
Adheres, thereby changing the discharge characteristics of the scorotron 2 and causing unevenness in the electric field formed between the dielectric drum 1 and the grid 2b, thereby causing serious defects in image quality. there were.

As a means for solving this problem, it has been proposed to provide a scorotron with a transfer fluid shut-off member (Japanese Utility Model Application Laid-Open No. HEI 2 (1994)).
However, the so-called toner floats in the apparatus and gradually enters the scorotron, causing the same problem as described above, and is not a sufficient solution.

[Problems to be solved by the invention]

The inventor of the present invention has intensively studied to solve such a problem, and as a result, the direction of the air flow flowing out from the ion flow outlet of the ion flow recording head is substantially the same as the direction of the charging means. By arranging the charging means toward the means, and further by arranging the air blowing means in the charging means, it is possible to prevent the charging means from being stained by toner and to record an image of good image quality over a long period of time. And completed the present invention.

Therefore, an object of the present invention is to prevent the residual toner floating up and flying in the apparatus frame from adhering to the charging means in the image recording apparatus for a long time. An object of the present invention is to provide an image recording apparatus capable of recording an image of good image quality.

[Means for solving the problem]

That is, the present invention provides an electrostatic latent image carrier formed in a cylindrical shape, charging means for gradually charging or charging the surface of the electrostatic latent image carrier to apply a uniform potential, An ion flow recording head for forming an electrostatic latent image on the surface of the applied electrostatic latent image carrier, a developing unit for developing the electrostatic latent image with a developer, and a transfer of the developed toner image onto a recording sheet An image recording apparatus having a transfer means for performing a transfer operation, wherein an outflow direction of an ion flow outlet of an ion flow recording head provided between the charging means and the developing means so as to face the electrostatic latent image carrier is set to the developing means. It is characterized by being arranged toward the side (claims 1 and 2).

Here, the ion flow recording head of the present invention may be appropriately selected as long as the outflow direction of the ion flow outlet is directed to the developing device side. A direction in which charging means is not provided in a direction of an angle within a range in which ions can be supplied and in a direction of an outflow air flow. The charging means may be appropriately selected as long as it is a conventionally known charging means capable of uniformly charging the surface of the electrostatic latent image carrier. Generally, a discharging wire serving as an ion generating means and an electrostatic latent image bearing A scorotron including a grid for forming a predetermined electric field with the body and a shield for preventing ions from being emitted in a random direction is used.

Further, in the present invention, the charging means is provided with an air flow blowing means to prevent the residual toner floating in the apparatus frame from entering the charging means and to prevent the residual toner from adhering to the charging means. (Claims 2 and 3).

Here, as the air flow blowing means, for example, a pressurized air is supplied from a compressor or the like into a shield accommodating a discharge wire of the charging means, and a direction opposite to a direction in which residual toner enters the shield. It is preferable that the air flow is formed.

Further, the air flow blowing means may be a means for branching a part of the air flow supplied to the ion flow recording head and blowing the air flow from the charging means toward the electrostatic latent image carrier. Good (claim 3).

[Action]

According to the present invention, the ion flow recording head is disposed near the electrostatic latent image carrier with the outflow direction of the ion flow outlet directed substantially in the opposite direction to the charging means disposed side. The residual toner scattered by the ion stream (air stream) from the flow recording head is not scattered to the charging unit side. Therefore, it is possible to prevent the toner from adhering to the charging unit and to prevent a change in the discharge characteristics of the charging unit. Also,
By arranging the air blowing means in the charging means, the adhesion of the toner to the charging means is prevented by this air flow, and the change in the discharge characteristics of the charging means can be prevented. Further, by branching off a part of the air flow supplied to the ion flow recording head and blowing out the air flow from the charging means toward the electrostatic latent image carrier, the image recording apparatus can be reduced in size while having the above-mentioned effect. Can be achieved.

〔Example〕

Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.

FIG. 1 shows a state in which an image is recorded on recording paper 6 by the image recording apparatus according to the present invention.

The image recording apparatus includes a dielectric drum 1 serving as an electrostatic latent image carrier, a scorotron 2 disposed around the dielectric drum 1 and uniformly charging the surface thereof, An ion current recording head 3 serving as an ion current recording means for supplying ions to form a latent image; a developing device 4 for developing the latent image with toner to form a toner image; A transfer device 5 that transfers the toner image to the recording paper 6 conveyed at the timing; and a toner remaining on the dielectric drum 1 having a charge having a polarity opposite to that of the charge held by the toner after transferring the toner image to the recording paper 6. And a cleaning device 8 that removes the toner remaining on the dielectric drum 1 and the like.

The scorotron 2 includes a discharge wire 2a connected to a discharge power supply (not shown), a shield 2b for generating ions by performing corona discharge between the discharge wire 2a, This is a scorotron composed of a grid 2c and the like for making the potential uniform.
Further, the ion flow recording head 3 is provided with the outflow direction of the ion flow outlet facing the developing unit 4 side, and the configuration is the same as that of the conventional example.

The above-described image recording apparatus is almost the same as the conventional image recording apparatus shown in FIG. 5, and therefore, the surroundings of the ion flow recording head 3 will be described in detail.

An ion stream is discharged from the ion stream recording head 3 to the uniformly charged dielectric drum 1 in the direction B in the drawing.
At the time of this outflow, not only the ions but also the air flow as the ion transfer fluid is also outflowed, so that the residual toner flies up.
However, since the outflow direction of the air does not face the scorotron 2 side, the residual toner does not scatter and adhere to the scorotron 2 direction.

Therefore, in the image recording apparatus of the present embodiment, since the residual toner sowed up by the ion current recording head does not adhere to the discharge wire 2a or the grid 2c of the scorotron 2, the scorotron 2 is kept uniform over a long period of time. It can be charged, and an image of good quality can be recorded.

FIGS. 2 and 3 show a second embodiment.

In this embodiment, the shield 2b of the scorotron 2
An air flow supply pipe 9 is disposed in the air flow supply pipe 9. A compressor (not shown) is connected to the air flow supply pipe 9, and the air flow from the compressor flows toward the dielectric drum 1 (direction D in the figure).
This prevents the residual toner floating in the apparatus frame from entering the scorotron 2.

Therefore, in the image recording apparatus of the present embodiment, since the residual toner floating in the apparatus frame does not adhere to the discharge wire 2a or the grid 2c of the scorotron, an image of good image quality is recorded for a long time. be able to.

FIG. 4 shows a third embodiment. In this embodiment, an air flow from a compressor (not shown) to which the transfer fluid passage P of the ion flow recording head 3 in the second embodiment is communicated is branched and supplied to the scorotron 2. It is connected to the pipe 9.

In the image recording apparatus of this embodiment, since the above-described operation is performed by using a scorotron compressor, it is possible to provide a downsized image recording apparatus according to the present invention.

〔effect〕

According to the image recording apparatus of the present invention, the residual toner floating up and scattered by the ion current recording head and floating in the apparatus frame does not adhere to the charging means, so that an image of good image quality can be obtained for a long period of time. An image recording apparatus capable of recording can be provided.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an image recording apparatus according to the present invention, FIG. 2 is an explanatory view showing a second embodiment of the image recording apparatus according to the present invention, and FIG. FIG. 4 is an explanatory view showing a scorotron according to a second embodiment of the recording apparatus, FIG. 4 is an explanatory view showing a third embodiment of the image recording apparatus according to the present invention, and FIG. 5 is a conventional image recording apparatus. The explanatory diagram, FIG. 6,
FIG. 9 is an explanatory diagram showing an ion flow recording head of a conventional image recording apparatus. [Explanation of Symbols] (1) ... dielectric drum, (2) scorotron,
(2b)… Shield, (2c)… Grid, (3)…
Ion flow recording head, (9) air flow supply pipe,

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B41J 2/415 G03G 15/02 G03G 15/05

Claims (3)

(57) [Claims] An electrostatic latent image carrier formed in a cylindrical shape, a charging means for removing or charging the surface of the electrostatic latent image carrier to apply a uniform potential, and a potential applied to the surface. An ion current recording head for forming an electrostatic latent image on the surface of the electrostatic latent image carrier, and a developing unit for developing the electrostatic latent image with a developer,
An image recording apparatus having a transfer unit for transferring a developed toner image onto a recording sheet, wherein an outflow direction of an ion flow outlet provided between the charging unit and the developing unit and facing the latent image carrier; An image recording apparatus, wherein the image recording apparatus is disposed toward the developing unit. 2. An electrostatic latent image carrier formed in a cylindrical shape, charging means for removing or charging the surface of the electrostatic latent image carrier to apply a uniform potential, and a potential applied to the surface. An ion current recording head for forming an electrostatic latent image on the surface of the electrostatic latent image carrier, and a developing unit for developing the electrostatic latent image with a developer,
Transfer means for transferring the developed toner image onto a recording sheet, wherein the charging means is provided with air flow blowing means for blowing air flow from the charging means toward the latent image carrier. In the recording apparatus, the outflow direction of an ion flow outlet provided between the charging unit and the developing unit so as to face the latent image carrier is directed toward the developing unit. apparatus. 3. An electrostatic latent image carrier formed in a cylindrical shape, charging means for removing or charging the surface of the electrostatic latent image carrier to apply a uniform potential, and a potential applied to the surface. An ion current recording head for forming an electrostatic latent image on the surface of the electrostatic latent image carrier, and a developing unit for developing the electrostatic latent image with a developer,
Transfer means for transferring the developed toner image onto a recording sheet, wherein the charging means is provided with air flow blowing means for blowing air flow from the charging means toward the latent image carrier. In the recording apparatus, the air flow blowing means of the charging means branches a part of the air flow supplied to the ion flow recording head, and blows the air flow from the charging means toward the latent image carrier. Image recording device.