JPS6151410A - Powder carrying screw - Google Patents

Abstract

PURPOSE:To reduce variation of load when using while bending the screw and to improve the carrying performance, in a screw for carrying powder through rotary motion, by employing resin or metal applied with resin coat as the material of screw. CONSTITUTION:Residual toner not transferred onto the paper is removed from the surface of photo-sensitive drum 1 by means of a cleaning blade and a sponge roller 3 arranged on the cleaner body 6 then carried through carrying screw 4 in the coupling pipe 7 and contained through a coupling adaptor 8 in a discard toner case 5. Here, the carrying screw 4 is made of resin or metal applied with resin coat. Consequently, when using while bending the carrying screw 4, the rigidity is low and the recovery force in the direction for enlarging the curvature R is also low, thereby the rotary load torque of carrying screw 4 and the load variation will decrease thus to prevent fluctuation of rotation of photo- sensitive drum 1.

Description

[Detailed Description of the Invention] [Scope of Application in Industry 2] The present invention relates to a conveying screw used for conveying powder, and mainly relates to a toner conveying screw for copying machines, laser printers, etc. be.

[Conventional technology]

Conventionally, toner transport screws used in developing units and cleaners of copying machines, etc. are made of metal such as piano wire or stainless steel wire for springs, and the cross-sectional shape of the wire is rectangular or circular. was common.

[Problem that the invention seeks to solve]

There is no particular problem when these screws are used in a straight line, but if the conveyance screw is bent due to space inside the device, unit placement, waste toner capacity, etc., the following disadvantages occur. there were.

FIG. 1 is a perspective view (partially sectional view) of the cleaner portion.

Briefly, toner remaining without being transferred to the paper is removed from the photosensitive drum 1 by a cleaning blade (not shown) installed in the cleaner body 6 and a sponge roller 3.
The waste toner is removed from the surface of the toner, is transported inside the connecting pipe 7 by the transporting screw 4, and is stored in the waste toner case 5 via the connecting adapter 8. Here, since the connecting pipe 7 is generally made of a silicone rubber hose or a Teflon tube, the contact area between the screw and the inside diameter of the pipe increases, and the sliding resistance increases significantly. It may even get stuck in the pipe and damage the pipe.

In addition, the metal conveying screw has relatively high rigidity, and since it is used by forcing a straight line, a restoring force acts in the direction of increasing the radius of curvature R. There is also an increase in the sliding load, which results in an increase in the rotational load torque of the screw and fluctuations in the rotational load.

In this case, if the rotation of the photosensitive drum and the rotation of the conveyance screw are connected by a gear train, etc., variations in the rotational load of the screw may cause uneven rotation of the photosensitive drum, which may adversely affect the image on the paper. be. Of course, it is possible to change the rigidity to some extent by selecting the cross-sectional dimensions, winding diameter, winding pitch, etc. of the conveying screw, but there is a usable limit depending on the degree of the radius R of one curve.

[Purpose of the invention]

The present invention aims to solve the drawbacks of the above-mentioned conventional examples, especially the problems when the conveying screw is used with a bent position.

〔Example〕

A feature of the present invention is that the material of the toner conveying screw is resin.

When using a plastin screw, even if it is bent as shown in Figure 1, it has lower rigidity than a conventional metal screw of the same size and shape, and has less restoring force in the direction of increasing the radius of curvature R. . Therefore, the rotational load torque and load fluctuation of the screw are reduced, and the above-mentioned adverse effects on the image are less likely to occur. Furthermore, by using a plastic screw, the above-mentioned defects are less likely to occur even if the radius of the screw is small (for example, R=35 mm) as shown in FIG.

Another example is a method of coating the surface of a conventional metal screw with resin.

FIG. 3 is a diagram showing its shape. Reference numeral 10 indicates a conventional metal screw, and reference numeral 11 indicates a resin coated around the screw. This resin coating has a thickness of, for example, 0.3 to 0.
Polyacecool of about 5+nm.

Tefton etc. is preferable.

Although this embodiment does not provide any improvement over the conventional method in terms of rigidity, it is an effective means for improving the slidability in the connecting pipe portion, and is also effective in preventing damage to the pipes.

〔Effect of the invention〕

In addition, in the description, only the case where the screw is used in a bent manner is described in detail, but according to the present invention, of course, even when the screw is used in a straight position, the weight can be reduced and the slidability can be improved. It is clear that there are effects such as

[Brief explanation of drawings]

1 and 2 are top views of the cleaner section, FIG. 3(a) is a top view of a screw showing another embodiment, and FIG. 3(b) is a sectional view taken along the line AA. In the figure, 4 is a toner conveying screw, 5 is a waste toner case, 6 is a cleaner body, 7 is a connecting pipe, 10 is a metal toner conveying screw, and 11 is a resin coating.

Claims (1)

[Scope of Claims] 1. A powder conveying screw, which is a screw-like member that conveys powder by interlocking rotation, characterized in that the material of the screw-like member is resin. 2. A powder conveying screw, which is a screw-like member that conveys powder by interlocking rotation, characterized in that the cross-section of the screw-like member is made of metal at the center and has a resin coating around it.