JPH01302278A - Image forming device - Google Patents

Abstract

PURPOSE:To facilitate cleaning and to evade cutting a corona wire by providing an opening for cleaning the corona wire on an image forming device capable of freely openable closable and dividable into >=two bodys. CONSTITUTION:In the movable or immovable body of the image forming device, the opening 25 is disposed for cleaning the corona wire 22 of a corona electrifier equipped with an electrostatifying house 18, etc. This opening 25 is usually closed by a cover through a spring 28, etc. When it is opened by turning the cover centering on a rocking shaft 27, a cleaning member is reciprocated there through the use of the cover for guide, so that the wire 22 is easily and preferably cleaned and evaded being cut.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an image forming apparatus such as a printer and a copying machine using an electrophotographic method, and more specifically, the present invention relates to an image forming apparatus such as a printer and a copying machine using an electrophotographic method. There is something about the opening for cleaning the wires of the device.

[Conventional technology]

An image forming device such as a printer or a copying machine that uses a process in which an electrostatic latent image formed on an electrophotographic photoreceptor through charging and light image exposure is visualized on recording paper through development, transfer, and fixing steps. is known and realized. The image forming apparatus includes a device that charges a photoconductive photoreceptor layer such as Se or OPC formed on a substrate to a predetermined polarity, and a toner image formed on the photoreceptor through a development process. Obi'J1
Devices that transfer charges onto the recording paper by applying charges of opposite polarity from the back side of the recording paper are generally 60 to 8
A so-called corona charging device is used, which applies a high voltage to a conductive wire with a diameter of 0 μm to cause corona discharge and generate ions of a predetermined polarity. The general structure of such a corona charging device will be explained in detail using FIG. The charging house 35 is made of a conductive member such as metal, and has a substantially U-shape surrounding the corona wire 36 for the purpose of functioning as a counter electrode for the corona wire 36 .
The photoreceptor drum 7 is disposed so as to closely face the outer peripheral surface of a photoreceptor drum 38 having a cylindrical shape, and is electrically maintained in a grounded state.

The corona wire 36 is stretched between a pair of blocks 39 insulated from the charging house 35 and connected to a high voltage power source 40 of a predetermined polarity. Continued. Corona zone M W with the above configuration
The position e extends parallel to the direction of the rotation axis of the photoreceptor drum 380 and performs the charging function described above.

The corona discharger described above has the problem of wire contamination caused by repeated use, which must be solved in order to form good images. Possible causes of this interlayer include a small amount of toner leaking and floating in the image forming apparatus, paper powder adhering to the surface of the photoreceptor drum, and an adhesion S area of discharge products such as 5iO1.

Due to these deposits, uniformity of discharge cannot be maintained and image defects occur. In order to deal with this problem, the corona wires of relatively large image forming apparatuses are periodically cleaned by specialized personnel as part of maintenance.

On the other hand, recently in the image forming apparatus, a photoreceptor drum,
By purchasing process elements such as a charging device, developing device, and cleaning device in an integrated unit and making the entire unit a consumable item that can be replaced, the overall size of the HR can be reduced, and maintenance that requires specialized knowledge can be reduced by the user. An image forming apparatus has been proposed and realized that frees up the following. However, even in such an image forming apparatus, the need for cleaning the corona wire cannot be solved, and the user is forced to do so. In particular, in the transfer charger, insulating transfer paper is inserted into the open opening 37 of the charging house 35 in order to avoid the danger of the recording paper jumping into the charging house 35 and cutting the corona wire 36 as shown in FIG. Jump prevention wire 4
1 has a groove structure on which it is stretched. For this reason, the cleaning work of the corona wire by an inexperienced user is more complicated than expected, as in addition to being careful not to cut the wire, the user is also forced to work while avoiding the above-mentioned jump prevention wire in the narrow space of the image forming apparatus. He had some shortcomings, such as:

[Problem to be solved by the invention]

The present invention has been made in consideration of the above-mentioned drawbacks of the prior art, and its purpose is to enable easy cleaning of the corona wire from an opening other than the opening of the corona charging device, and to The present invention aims to realize an image forming apparatus that avoids cutting of corona wires during cleaning.

[Means to solve the problem]

In order to achieve the above object, the present invention provides an image forming apparatus that uses an electrophotographic method and can be opened and closed into at least two bodies, a stationary body and a movable body, using a supporting means. The present invention is characterized in that an opening for cleaning the wire of the corona charging device is provided on the - side.

〔Example〕

An embodiment of the present invention will be described below based on the drawings. FIG. 1 is a sectional view schematically showing the main parts of a laser beam printer provided with a wire cleaning opening according to the present invention. In the figure, 1 is a photosensitive drum made of a photoconductive material such as 5e10PC in a drum shape. When the photosensitive drum 1, which is rotatably supported by the printer main body, is rotatably driven in the direction of arrow A by a drive source (not shown), the surface of the drum is uniformly corona charged by the charging device 2.

- The laser beam modulated by the image signal is reflected by the rotating polygon mirror 3, passes through the imaging optical system 12, and sweeps the charged portion on the photoreceptor drum 1 in the direction of the rotation axis to perform optical image exposure. , an electrostatic latent image is formed on the drum surface. This electrostatic latent image is visualized by toner when passing through a developing device 4 that forms a magnetic brush. The toner image formed in this manner is transferred from a transfer paper stacker 8 to a transfer position in synchronization with the toner image on the photoreceptor drum 1 by a transfer belt TR device 5 that performs corona discharge with a polarity opposite to the charging polarity of the toner. The image is transferred onto the fed transfer paper 9. After the transfer, the transfer paper 9 is separated from the photoreceptor drum 1 and transferred to the fixing device 1.
0 and is discharged onto the paper discharge tray 11. On the other hand, about 20 to 3
0% of untransferred toner remains, and this residual toner is
It is removed by the cleaning device 6. After the drum portion has been cleaned, the charge is removed to a certain level by the charge removal lamp 7, and then the drum portion is prepared for the next image forming process.

As mentioned above, since the transfer paper stacker 8 has a structure in which it is disposed above the photoreceptor drum 1, the paper feeding path of the transfer paper 9 is centered around the rotation center of the photoreceptor drum 1, as shown by the broken line in the figure. Since the paper feeding path intersects the horizontal plane through which the photoreceptor drum 1 passes near the outer peripheral surface, the image forming apparatus shown in this embodiment has the feature that the desktop projected area is smaller than the side projected area, and can be used exclusively for desktop use. It becomes possible to suppress the area. FIG. 2 is a diagram showing a state in which the front cover 13 of the image forming apparatus in this embodiment is opened. A transfer charging device 5 and a temporary paper guide 14 are arranged inside the front cover 13.
The movable body 15 is constituted as a whole. The movable body 15 is swingably supported by a stationary body 17 of the image forming KH by a support shaft 16, and is engaged with the stationary body 17 in a closed state by an engagement member (not shown).

The opening for cleaning the corona wire of the transfer belt TT device will be explained in detail with reference to FIG. Components serving the same purpose are designated by the same reference numerals. The charging house 18 is made of a member having tetraelectricity such as metal, and has a pair of side plates 19a and 19b.
and a back plate 21 having a house frontage 20, and is formed in a substantially U-shape surrounding the corona wire 22 for the purpose of acting as an opposing [+i] for the corona wire 22. They are disposed within the front cover 13 so as to be close to each other at a predetermined distance m from the outer peripheral surface of the front cover 13, and are kept electrically grounded. The corona wire 22 is made of a tungsten wire with an outer diameter of 80 μm, and is stretched between a pair of insulating blocks (not shown) fixed to both ends of the charging house 18 and connected to a high voltage power source (not shown). An insulating transfer paper prevention wire 24 is stretched over the opening 23 of the charging house 18 . A wire cleaning opening 25 is formed narrowly in the same direction as the extending direction of the corona wire 22 in the front cover 13 facing the house opening 20, and the wire cleaning opening 25 is sealed so as to be openable and closable. A shutter 26 is provided to stop the vehicle. The shutter 26 is normally biased by a spring 28 so as to be able to swing freely relative to the front cover 13 on a swing shaft 27 to close the wire cleaning opening 25 . t of the corona wire 22
At the time of flH, the shutter 26 is swung open in the direction shown by arrow B, a wire cleaning member to be described later is inserted through the wire cleaning opening 25, and the toner is removed by sliding it back and forth in the direction in which the corona wire 22 is stretched. , paper powder, Stow, etc., adhering to the wire are removed. On the other hand, the shutter 26
When the synchronization 1 is opened, an interlock mechanism (not shown) is activated, and the power to the image forming apparatus is cut off, thereby ensuring the safety of the operator. According to such a mechanism, the corona wire 22 can be cleaned from the opposite side of the opening 23 where the transfer paper intrusion prevention wire 24 is stretched, so that work efficiency is greatly improved.

Using FIG. 4(a) and FIG. 4(b), the cleaning member 2
The structure and cleaning method of No. 9 will be explained in detail. The cleaning member 29 includes an arm portion 30 having a substantially horseshoe shape and a cleaning portion 31 made of a material such as felt. What is the shape of the outer surface 32 of the arm portion 30? A feature has been added in which the width becomes narrower as it approaches the FHM section 31, and when cleaning the engagement section 33 provided on the front cover 13, tIJtf! do. The cross-sectional shape of the engaging portion 33 perpendicular to the direction in which the corona wire 22 is stretched has a characteristic that the width becomes narrower as it approaches the corona wire 22 . Due to the above-mentioned characteristics of the outer surface 32 and the engaging portion 33 of the cleaning member 29, the arm portion 30 receives pressure as the cleaning member 29 is inserted into the wire cleaning opening 25, and the gap between the cleaning portion 31 becomes smaller. When the abutting part 34 formed on the arm part 30 comes into contact with the engaging part 33, the arm part 30 is elastically deformed and the cleaning part 31 assumes a form in which the corona wire 22 is held. One operation of cleaning the corona wire 22 is also carried out by sliding the cleaning member 29 back and forth along the engaging portion 33 as shown by the arrow in FIG. 4(b) using the cane. For this reason, it is desirable that the material of the arm portion 30 be an elastically deformable material such as a resin material. In this way, the corona wire 22
Since the corona wire 22 is sandwiched from both sides and the contact portion 34 is formed to prevent the cleaning member 29 from accidentally fitting in, the corona wire 22 is IN hW in all aspects, and the wire is not loosened or cut. Being subjected to meaningless stress caused by stress is also reflected.

In the embodiments shown above, the cleaning opening and its surrounding structure, the shape and material of the cleaning member, the cleaning method, etc. are not limited to the embodiments shown above, and the design may be modified in order to perform a good cleaning work. can be freely administered. - In the strength tree embodiment, the Wt of the corona wire of the transfer charging device
Although the cleaning has been described in detail, the same effect can be obtained even if the object is a charging device using corona discharge, such as a charging device for a photoreceptor, a separation device, a static elimination device, etc.

〔Effect of the invention〕

According to the present invention, in an image forming apparatus that can be divided and opened and closed into at least two bodies, a stationary body and a movable body, by a support shaft, a wire of the corona release!! By arranging the cleaning opening, it is possible to clean the wire from other than the opening facing the charged object, making it easier for users who have not developed specialized knowledge or are unfamiliar with equipment maintenance work. It is possible to perform convenient, quick, and reliable cleaning work without damaging or cutting the wire.In addition, the cleaning opening is formed narrowly, making it difficult to open the main body of the device during work. Since there is no need to open the photoreceptor in large sections, it is possible to minimize exposure of the photoreceptor to light irradiation due to undesirable disturbance light, and to prevent foreign matter from entering the precision mechanical device.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an image forming apparatus provided with a wire cleaning opening according to the present invention. FIG. 2 is a sectional view for explaining a state in which the movable body of the image forming apparatus according to the present invention is opened to the immovable body. FIG. 3 is a diagram for explaining the wire ft sweeping opening of the band W1 device in the present invention. FIGS. 4(a) and 4(b) are diagrams for explaining the cleaning state of the wire by the cleaning member. FIG. 5 is a diagram for explaining a conventional example. In the figure 1... Photoreceptor drum 2... Band ffi device 3...
Rotating polygon mirror 4...Developing device 5...Transfer charging device 6...Cleaning device 7...Static elimination lamp 8
...Transfer paper stuffer 9...Transfer paper 10.
... Fixing device 11 ... Paper ejection tray 12 ... Imaging optical system 13 ... Front cover 14 ... Paper guide plate 15
...Movable body 16...Support shaft 17...Imovable body 18.35...Charging house 1ea119b...
・Side plate 20...House frontage 21...Back plate 22
．． 36...Corona wire 23. 37...Opening port 24.41...Transfer paper intrusion prevention wire 25...Opening for glossy t, ma 26...Shutter 27...Swing shaft 28 ... Spring 29 ... Cleaning member 30
...Arm part 31...Cleaning part 32...Outer surface 33...Engagement part 34...Abutting part 39...
Block 40... High voltage power supply and above Figure 1 (CI) Figure 3 Figure 5

Claims (1)

[Claims] (1) In an image forming apparatus that uses an electrophotographic method and can be divided into at least two bodies, a stationary body and a movable body, by means of a supporting means, at least one of the stationary body or the movable body is provided with wire cleaning equipment for a corona charging device. An image forming apparatus characterized in that an aperture is provided.