JPH0695477A - Electrifier - Google Patents

Abstract

PURPOSE:To obtain stable uniform electrification and an electrifier not being affected by means of dust by dividing an electrifying wire to which a high voltage is applied into plural short segments and slantingly extending plural divided short segments of the electrifying wire at a constant angle with respect to a drum axis line. CONSTITUTION:An electrifier main body 1 is set for the length of a printing region L2 or more. The electrifying wire 21 is slantingly extended at the constant angle theta with respect to the drum axis line L1 between a contact point 4 connected with a connector 6 and a contact point 31. Similarly, short wires 22-27 are extended at the angle theta with respect to the drum axis line L1 between contact points 41 and 32, 42 and 33, 43 and 34, 44 and 35, 45, and 36 and 46 and 3, respectively. The segments of a part of adjacent electrifying wires 21 and 22-27 are arranged so as to overlap because the paired contact points 31 and 41 and 32 and 42-36 and 46 are shifted in the direction of the axis line L1. These paired contact points are electrically connected with the electrifier main body 1 by a connecting part 5 and the high voltage is applied to the electrifying wires 21-27.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic apparatus such as a printer or a copying machine, and more particularly to a charger for charging a photosensitive drum or transferring a recording sheet.

[0002]

2. Description of the Related Art Conventionally, this type of charger charges a photosensitive drum or a recording paper by applying a high voltage to one or a plurality of charging wires having a length equal to or greater than a print width region. I was transcribing.

[0003]

In the conventional charger, since the charging wire is supported at both ends, the central portion vibrates when a high voltage is applied, which causes an unstable distance to the photosensitive drum. However, it was difficult to uniformly charge. Due to this, there is a problem that the print quality is deteriorated.

In addition, when dust in the air adheres to the wire, only that part of the wire suffers from charging failure, which deteriorates the printing quality.

An object of the present invention is to solve the above problems and to provide a stable and uniform charging and a charger which is not affected by dust.

[0006]

In order to achieve the above object, in a charger according to the present invention, a high voltage discharge is performed within a printing area set in the drum axial direction of a photosensitive drum for forming an electrostatic latent image. In the charger, a charging wire to which a high voltage is applied is divided into a plurality of short line segments, and the short line segments of the plurality of charge wires are obliquely stretched at a constant angle with respect to the drum axis. It was done.

Further, among the short line segments of the charging wire divided into the plurality of parts, adjacent line segments partially overlap each other in the axial direction of the photosensitive drum.

[0008]

According to the present invention, a plurality of charging wire line segments which are short with respect to the width of the printing area and which are stretched obliquely with respect to the axis of the photosensitive drum are provided. Since each charging wire line segment supplements the charging area of the adjacent charging wire line segment, stable and uniform charging can be performed.

[0009]

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

FIG. 1 is a plan view showing an embodiment of the present invention.

In the figure, a photosensitive member for forming an electrostatic latent image is generally formed in a drum shape. When an electrostatic latent image is formed on the photosensitive drum, the drum axis L _{1 of the} photosensitive drum is formed.
A print area L ₂ is required along the line. This means that the printing area L ₂ is required as the charger even when the visible image developed on the photoconductor is transferred onto the recording paper. At least the charging is performed within this print area L ₂ .

Here, in the charger according to the present embodiment, the charger main body 1 is set to have a length equal to or longer than the print area L ₂ .
A connection connector portion 6 is provided at one end thereof to be inserted and connected to a power connector of the apparatus body.

Further, the charger main body 1 has a pair of contacts 3 ₁ and 4 ₁ , 3 ₂ and 4 ₂ , 3 which are electrically connected to each other by a connecting portion 5.
₃ and 4 ₃ , 3 ₄ and 4 ₄ , 3 ₅ and 4 ₅ , 3 ₆ and 4 ₆ are displaced in the direction of the drum axis L ₁ and provided at regular intervals in the left-right direction. A conductor, a conductive wire, or the like is used as the connecting portion 5.

[0014] Here, this embodiment, in order to divided into a plurality of charging wires to which a high voltage is applied to the short line segments, to separate one charging wire to a plurality of wires 2 ₁ to 2 _7, the plurality the wire 2 ₁ to 2 ₇ is an example of a case of using as the short line segments.

That is, a short charging wire 2 ₁ is provided between the contact 4 and the contact 3 ₁ which are electrically connected to the connector portion 6.
Is obliquely extended at a constant angle θ with respect to the drum axis L ₁ , and similarly contacts 4 ₁ and 3 ₂ , 4 ₂ and 3 ₃ , 4 ₃ and 3 ₄ , 4
_The short charging wires 2 ₂ , 2 ₃ , 2 ₄ , 2 ₅ , 2 ₆ , 2 ₇ between ₄ and 3 ₅ , 4 ₅ and 3 ₆ and 4 ₆ and 3 have a constant angle θ with respect to the drum axis L _1. And stretch it diagonally.

In this case, the adjacent charging wires 2 ₁ ,
Partial line segments of 2 ₂ , 2 ₃ , 2 ₄ , 2 ₅ , 2 ₆ , 2 ₇ are paired contacts 3 ₁ , 4 ₁ , 3 ₂ , 4 ₂ , 3 ₃ , 4 ₃ , 3 ₄ , 3 ₄ . ₄ , 3, ₅ ,
Since 4 ₅ , 3 ₆ and 4 ₆ are displaced in the drum axis L ₁ direction, they are arranged so as to overlap.

The charger main body 1 is connected to the high voltage power source of the apparatus body by a connector section 6, high voltage is applied to the charging wire 2 ₁ to 2 _7.

According to this embodiment, the charging wires 2 ₁ , 2 ₂
For ~ 2 ₇ length of are shortened compared to the length of the conventional charging wire, it becomes possible generation of vibrations is suppressed even when high voltage is applied, the distance between the charging wire and the photosensitive drum Will be kept constant.

Further, since the adjacent charging wires overlap each other along the drum axial direction of the photosensitive drum,
Not only stable and uniform charging is possible, but also when dust adheres, adjacent charging wires complement each other, which enables stable and uniform charging.

In the above embodiment, one charging wire is divided into a plurality of wires when the charging wire to which a high voltage is applied is divided into short line segments, but the invention is not limited to this.

That is, using one charging wire,
This locked the contact 4 of the upper end shown in FIG. 1 first and then engaged with the contact 3 ₁ stretched between the contacts 4 and 3 _1, the contact 4 and 3
_Use the charging wire line segment between ₁ as a short line segment,
Arranged this short line segment obliquely with a certain angle θ with respect to the drum axis L _1, further lock the charging wire engaged with the contact 3 ₁ to the contact 4 _1, between the contacts 3 ₁ and 4 ₁ by performing using charging wire segment as the connecting portion 5, the task of further locking the charging wire engaged with the contact 4 ₁ to contact 3 ₂ sequentially contacts 4 ₁ and 3 _2, 4 ₂ and 3 _3, 4 ₃ and 3 ₄ , 4 ₄
And 3 ₅ , 4 ₅ and 3 ₆ , 4 ₆ and 3 are used as short line segments, and these short line segments are used at a constant angle θ with respect to the drum axis L ₁ . May be arranged diagonally.

In this case, the contacts 3 ₂ and 4 ₂ , 3 ₃ and 4 ₃ , 3 ₄
The charging wire line segments between and 4 ₄ , 3 ₅ and 4 ₅ , 3 ₆ and 4 ₆ serve as the connecting portion 5.

[0023]

As described above, according to the present invention, a plurality of short charging wire line segments are obliquely stretched, and adjacent charging wires are overlapped with each other, whereby stable uniform charging is performed on the photosensitive drum. Further, even if the charging wire is contaminated by dust or the like, the adjoining charging wire supplements it, so that good printing quality can be maintained for a long period of time.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of the present invention.

[Explanation of symbols]

1 Charging device main body 2 _{1 to} 2 ₇ Charging wire 3, 3 _{1 to} 3 ₆ , 4, 4 ₁ to 4 ₆ contacts 5 Connection part 6 Connection connector part

Claims (2)

[Claims] 1. A charging device for discharging a high voltage in a printing area set in the drum axial direction of a photosensitive drum for forming an electrostatic latent image, wherein a plurality of charging wires to which a high voltage is applied are arranged in short line segments. The charging device is characterized in that a short line segment of the charging wire divided into a plurality of pieces is stretched obliquely at a constant angle with respect to the drum axis. 2. The short line segments of the charging wire divided into the plurality of adjacent line segments are partially overlapped in the axial direction of the photosensitive drum. 1. The charger according to 1.