CN2575719Y - Mining flame-proof type multifunction digital switch - Google Patents

Abstract

The utility model relates to a charging roller used for an image shaping device, which comprises a roller body and a roller shaft, wherein, the middle of the roller body is positioned in a working area, and both ends of the roller body are positioned in a non-working area; the roller shaft extends outwards from both end faces; the roller body is provided with a radial bulge in the non-working area. The bulge contacts with a non-working area of a photosensitive drum. Therefore, the charging roller can be disengaged from contacting with the non-working area of the photosensitive drum. The cross contamination caused by the contact of working areas can be avoided effectively. The quality of printing can be ensured.

Description

Charging roller

Technical field

The utility model relates to the charging roller that image processing system is used.

Background technology

With the carbon dust is the image processing system of toner, as duplicating machine, laser printer etc., before photo-sensitive cell forms latent image, by charging roller photo-sensitive cell is carried out uniform charging.At present, adopting one of architectural feature that this mode charges is that charging roller directly contacts with photo-sensitive cell, typical case's representative as this design philosophy, CN1250890 Chinese invention patent ublic specification of application discloses " image processing system of roller charging and this device of employing " by name, can guarantee at work and the contacting of photosensitive drum surface for making charging roller, under the charging roller axle bed, also be provided with spring, this spring is radially urging the charging roll shaft, make charging roller just be able to balance at the radial constraint that is subjected to from photosensitive drums, promptly as shown in Figure 5, charging roller 3 surfaces directly contact with photosensitive drums 5 surfaces, uniform charging is carried out on the surface of 3 pairs of photosensitive drums 5 of charging roller, the zone identical with the print media width, the surface of charging roller 3 can be described as workspace 7, and the zone at two ends is a nonclient area 8.

Theoretically, cleaning device is made desirable cleaning to photosensitive drums, and in fact, photosensitive drums can not be cleaned fully, during in particular for high speed copier or printer.Promptly after the photosensitive drums cleaning course is finished, still have a spot of remaining toner to stay the surface, workspace of photosensitive drums, because charging roller contacts with photosensitive drums and together with its rotation, this residual carbon dust is transferred on the charging roller, cause charging roller inhomogeneous charging to take place owing to staiing, this makes image quality descend on the one hand, and on the other hand, the durability of charging roller descends.In addition, because impurity such as dust are easily adhered on the roller surface that charging roller has Sponge or rubber bodies material usually, also can the photosensitive drums of direct contact be polluted, this equally also can reduce print quality.

Summary of the invention

For solving the print quality decline problem that above-mentioned cross pollution causes, the applicant is by observing thinking for many years, and the experiment back is found, for reaching purpose to the photosensitive drums uniform charging, charging roller and photosensitive drums should keep in touch this traditional concept and incorrect, parallelly between charging roller and the photosensitive drums draw back a suitable minim gap, still can normally carry out uniform charging photosensitive drums.

The purpose of this utility model be provide a kind of can effectively avoid and photosensitive drums between produce the charging roller of cross pollution.

For this reason, the technical solution adopted in the utility model is that a radially protuberance is set in the charging roller nonclient area.This protuberance contacts with the nonclient area of photosensitive drums, thereby the workspace of charging roller and photosensitive drums is disengaged, and has avoided effectively because of the workspace contacts the cross pollution that causes print quality being protected.

Above-mentioned radially protuberance can be a ring bodies, and promptly roll body is a reducing cylinder that the two ends radius is bigger basically.It is different according to different type of machines that protuberance exceeds the height on roller surface, relevant with the charging voltage value of charging roller, for most types, protuberance exceeds roller surface 0.03-0.04 millimeter usually, and just the difference of the radius of ring bodies outer shroud and roll body workspace radius is the 0.03-0.04 millimeter.

Description of drawings

Fig. 1 is the stereoscopic figure according to charging roller of the present utility model;

Fig. 2 is the structure principle chart of first embodiment;

Fig. 3 is the structure principle chart of second embodiment;

Fig. 4 is the structure principle chart of the 3rd embodiment;

Fig. 5 is the synoptic diagram that existing charging roller cooperates with photosensitive drums work.

Do explanation in further detail below in conjunction with several embodiment of the present utility model and accompanying drawing thereof.

Embodiment

Referring to Fig. 1, be provided with radially protuberance 2,4 in the nonclient area of charging roller 3, common protuberance has the cylindrical surface with axle 1, charging roller 3 coaxial lines.

The structure principle chart of technical solutions of the utility model as an illustration, for explain convenient for the purpose of, all accompanying drawings are all exaggerated to protuberance thickness diametrically, its actual (real) thickness is between the 0.03-0.04 millimeter.

First embodiment:

Referring to Fig. 2, be positioned at the protuberance the 2, the 4th at charging roller 3 two ends, dope layer, available polytetrafluoroethylmaterial material, also other high-abrasive materials such as available graphite, protuberance 2,4 contacts with photosensitive drums 5, and between the work section of charging roller 3 and photosensitive drums 5, a 0.03-0.04 mm clearance is arranged.The characteristics of present embodiment are that thickness is even, control easily in the processing and manufacturing process.

Second embodiment:

Referring to Fig. 3, be positioned at the protuberance the 2, the 4th at charging roller 3 two ends, sleeve pipe, can adopt polytetrafluoroethylene material or other high-abrasive materials, sleeve pipe can directly tightly be enclosed within the charging roller two ends, also can adopt the mode of thermal shrinkage, make between charging roller 3 and the photosensitive drums 5 work sections and produce the 0.03-0.04 mm clearance.The characteristics of present embodiment are that manufacturing processing is quick, simple to operate.

The 3rd embodiment:

Referring to Fig. 4, be positioned at the protuberance the 2, the 4th at charging roller 3 two ends, sleeve because more aforementioned two examples of sleeve have bigger radial dimension, can adopt moulding, and bush material can adopt high-abrasive materials such as polytetrafluoroethylene, polyoxymethylene, polyamide.

Claims (3)

1, charging roller is positioned at the roll body that workspace and two ends are positioned at nonclient area in the middle part of comprising, and from the overhanging roll shaft of both ends of the surface;

It is characterized in that:

Roll body has radially protuberance in nonclient area.

2, charging roller according to claim 1,

It is characterized in that:

Described radially protuberance is a ring bodies.

3, charging roller according to claim 1 and 2,

It is characterized in that;

Described protuberance exceeds roller surface 0.03-0.04 millimeter.

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