JPS58172667A - Corona discharger for image transfer - Google Patents

Abstract

PURPOSE:To prevent direct exposure of the surface of a recording medium to transfer corona discharge, by covering one end of the discharge face of a transfer corona discharger with grids, and applying voltage reverse in polarity to the corona discharge in accordance with the width of recording paper to mask it. CONSTITUTION:Electrically isolated grids 21, 22 are installed in parallel on the end of an effective discharge region (b) in an image recording apparatus, and positive voltage can be selectively applied to each grid 21, 22 from a grid voltage source E2 with switches SW1, SW2. A main voltage source E1 for a transfer corona discharger 2 emits negative corona discharge opposite in polarity to toner charged from a charge wire electrode W1. Prescribed recording paper is selected and positive voltage is applied to each grid 21, 22, at that time, negative corona ions discharged from the electrode W1 are cut off with them, thus permitting electrical masking corresponding to the recording paper B, C to be used.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transfer corona discharge device in an electrophotographic or electrostatic recording type transfer type art recording device.

Generally, the photosensitivity or r! moves in the sub-scanning direction. s1!
In an electrophotographic or electrostatic recording transfer type image recording device in which each line of own information in the main scanning direction is sequentially written by a recording head on the surface of an E-type recording medium, , width of recording medium′ (main scanning width)
A4 for V maximum. It is 5K so that images of various sizes such as B4°85 can be recorded.

In addition, even in the case of a transfer corona discharger, it is possible to set a corona discharge area in the main scanning direction that extends across the width of the recording medium to cope with the transfer of an image with a maximum width size. However, when transferring a smaller image with a width of 1K, a recording paper of a corresponding size is fed to the transfer section, so that the surface of the recording medium is partially exposed to the direct transfer corona. Incidentally, FIG. 1 shows the relationship between the effective discharge area and the width of recording paper of various sizes in the transfer corona waste electrical appliance.

In the figure, a indicates the area of the recording medium 1, b indicates the effective discharge area of the transfer corona discharge device 2 (it is set to be equal to the width of the maximum size recording paper A), and r and d indicate the minimum size. record a
Width V of C and C respectively indicate the width of recording paper B having an intermediate size. Further, in the figure, Wl indicates a charge wire electrode of the transfer corona discharger 2.

If the recording medium is partially exposed to the transfer corona,
If the surface potential fluctuates greatly, the quality of the recorded image will deteriorate because the potential will not be the same as that of other parts during static elimination or uniform Teiden process during the next copy cycle, and the quality of the recorded image will deteriorate. The transfer corona with negative polarity generates a large amount of ozone (which causes problems such as deterioration of the recording medium Y).The present invention was made in consideration of these points. (Providing a transfer corona discharge device that electrically masks unnecessary discharge parts of the transfer corona discharge device according to the recording size of image 1 so that the surface of the recording medium is not directly exposed to the transfer corona radiation. It is something to do.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the accompanying drawings.

@Figure 2 is an electrostatic recording type image recording device ILv.
In this example, a uniform band 11IL of the recording medium IEfi is formed by the AC corona discharger 3 and the scorotron 4 according to the movement of the endless belt-shaped recording medium l in the rigid scanning direction, and then one line in the main scanning direction is formed. An electrostatic latent image corresponding to one line of own information is sequentially formed by a recording head 5&C equipped with a stylus, and after the formed latent image is visualized by a V imager 6, it is transferred. By corona discharger 2? The electrostatic recording process is performed by transferring the paper onto the recording paper 8 fed from the straw rough at a predetermined timing, and then fixing the transferred recording paper 8 using the fixing device (not shown) K. Configured to run sequentially. Note that the surface of the recording medium after the transfer is cleaned by a cleaner 9 so as to be ready for the next recording cycle.

In such an image recording apparatus, in particular, the present invention uses a transfer corona discharger 2YM3 and 5#IC as shown in Figures @4.
, electrically floating grids 21.22g are provided in parallel at one end of the effective discharge area bK, and those! Grid 21.22Vc 4 ychi SWI, 8W2
Selectively by grid power supply E2 K by plus i-
voltage? It is possible to apply 1'c. In the figure, W1 is the charge wire electrode Y of the transfer corona discharger 2, W2 and W3 are the wire electrodes of the grid 21 and 22, and Pl is the connector pin of the charge wire electrode W1. ,
P2. P3 is the grid wire electrode W2. Each connector pin of W3 is shown. Also, El in the figure
is the main power source of the transfer corona discharger 2, and is set to 1C so that a negative corona discharge with a polarity opposite to that of the toner is generated from the charge wire electrode Wl.

Therefore, in the transfer corona discharger according to the present invention configured as described above, the width e F/ of the grid 21 is 6 widths (a-b) between the recording paper A and the recording paper B in FIG.
) K, and the width fg of grid n is also recorded as Kikamagi B
6 widths in L, C and! (When using recording paper B other than full-size recording paper A, set only switch 8W1 to ON and grid 2
If a positive voltage is applied to the charge wire electrode Wl, and if a recording AC is used, switches 8W1 and 8W21 are turned on at the same time and a positive voltage is applied to each of the grids 21 and 22, thereby discharging from the charge wire electrode Wl. The negative corona ions are interrupted at the grid 21 or each grid 21.22, and the recording paper B, C used is
It becomes possible to apply a suitable electric mask.

Further, when using a full-size recording RAV, switch 8W1. If both SW2 and Y are turned off,
The transfer corona discharge is performed on the recording paper A in the effective discharge area by without being interrupted in any way by the grids 21 and 22.

Note that the switches SWI and SW2 may be switched manually by the operator depending on the size of the recording paper to be used. The paper feed cassette 12 containing each paper A, B, and C
A, 12B, 120 pieces are prepared separately and 11,111 pieces of 12B are prepared separately.
A selector 81 Y is provided in one part, and a selector 82 V is provided in the 10,000 side part of 12C. Micro switch SWI.

8Wl' is provided, and when the paper feed cassette 12B is inserted, a twist micro switch SW is set on the selector S1.
When the paper feed cassette 12C is inserted, both the microswitches SWI and 8W2 are turned on from the selector 82#c to automatically control the grids 21 and 22 in the transfer corona discharger 2. It is possible to make it happen. Alternatively, grid 21, 220 # may be performed by directly inspecting the width of the fed recording paper using a sensor or the like.

Note that the transfer corona discharger according to the present invention is an electrostatic +ii
Needless to say, the present invention is applicable not only to the case of an ITK apparatus but also to an electrophotographic image recording apparatus that sequentially performs electrophotographic processes on the surface of a photosensitive recording medium.

As described above, in the transfer corona discharger according to the present invention, an image developed with toner is transferred onto the surface of a recording medium in an electrophotographic or electrostatic recording transfer type image recording device. In a transfer corona discharge device, a grid is controlled to cover at least one end of the discharge surface in the effective discharge area of the transfer corona discharger, and a voltage with a polarity opposite to the corona polarity discharged according to the paper width of the recording paper is applied to the grid to generate electricity. It has the excellent advantage of being able to effectively prevent the surface of the recording medium from being directly exposed to transfer corona.

[Brief explanation of the drawing]

Figure @1 is a diagram showing the relationship between the effective discharge area and the recording paper width in % size in a transfer corona discharge device, and Figure @2 is a simplified configuration of a general electrostatic recording type image recording device. 3 is a perspective view showing an embodiment of the transfer corona group 111c6 according to the present invention, FIG. 4 is a diagram illustrating a specific means for automatically performing the process according to the number of times. 1... Recording medium 2... Transfer corona discharger 21.2
2...Crit 10...Image recording device main body 12A
, 12B, 12C--Paper cassette applicant Kiyoshi Torii Figure 3 Figure 4

Claims (1)

[Claims] Transfer type image recording device using electrophotography or electrostatic recording type @
In a transfer corona discharge device that transfers an image developed with toner from a recording medium@ in a VC onto a recording paper, a grid is provided to cover at least one end of the discharge surface in the effective discharge area of the transfer corona discharge device, and a grid is provided to cover the width of the recording paper. A transfer corona discharge that can be applied with an electrical mask by applying a voltage of opposite polarity to the corona polarity that is discharged accordingly.