JPS6334567A - Developing device - Google Patents

Abstract

PURPOSE:To enable supply of a uniformly and stably electrically charged toner to a magnet sleeve by mounting agitating vanes at specific intervals and dispositions with respect to the spirals of a 1st toner conveying screw to at least said screw. CONSTITUTION:The 1st toner conveying screw 172 which agitates the supplied toner and transfers the toner in the longitudinal direction and the 2nd toner conveying screw 173 which agitates the toner and transfers the same in the opposite direction are provided with the spirals 172A, 173A directed to the respectively opposite directions. The agitating vanes 177 are mounted to the top and bottom of the spirals 172 of the 1st toner conveying screw 172 by shifting the phase to the opposed directions of every two pitches. The pitches where the vanes 177 exist and the pitches where said vanes do not exist are thereby alternately connected to each other; therefore, the agitating power of the toner and developer is intensified and since the intrinsic circulating power is held by the device, the excellent agitating and circulating power is exhibited.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a developing device, and is used as a developing device for electronic copying machines, microfilm readers, printers, and the like.

(Prior Art) A printing device 1 used for electronic copying etc. generally has a toner supply port 2, a first toner conveying screw 3, and a second toner conveying screw 4, as shown in FIG. is provided in a case G via a partition wall 7, and a magnetic sleeve 5 for transferring toner to a photoreceptor drum (not shown) is provided at one end of the case.
is provided.

The first toner conveying screw 3 and the second toner conveying screw 4 are respectively provided with spirals 3A and 4A in opposite directions for stirring and conveying the toner, and the toner is supplied from the toner supply port 2. The toner is first transported by the first toner conveying screw 3 in the direction of the 14th port while being stirred together with the developer, then transferred to the second toner transporting screw 4, and is then transferred to the 14th mouth while continuing to be stirred. →It is designed to be transported in the direction of A.

Therefore, the toner is circulated while being stirred together with the developing agent, and after being uniformly charged by repeating this @ ring,
It is supplied to the circumferential surface of the magnetic sleeve 5 and transferred to a photosensitive drum (not shown).

(Problems to be Solved by the Invention) However, in the above-mentioned conventional developing device, although the circulating transfer of toner and developer is sufficiently achieved, stirring is insufficient, so the charging safety of the toner is affected. There is a problem with missing parts.

If the toner is sent to the photoreceptor drum in a state where it is not sufficiently agitated in this way, the toner may scatter to the outside of the developing device due to the centrifugal force of the magnetic sleeve 5 or the impact when it comes into contact with the photoreceptor drum. , the main body of the apparatus, peripheral parts, etc. may be dyed, causing uneven discharge, insufficient light G, uneven light distribution, etc., resulting in the problem of degrading the quality of the copied image.

The present invention was achieved as a result of studies to solve the problems of the conventional developing device described above.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an apparatus capable of supplying toner to a photoreceptor drum with excellent toner agitation ability and circulation ability and with excellent charging stability.

[Configuration 1 of the Invention (Means for Solving the Problems) In other words, the present invention comprises a toner supply port, a first toner conveying screw that stirs the supplied toner and transports it in the longitudinal direction, and A second stirring and transporting in the opposite direction to the above.
and a magnetic sleeve for transferring the agitated toner to the photoreceptor drum, the developing device comprising at least the first toner FI"
It is characterized by a stirring blade attached to the S screw.

(Function) The developing device of the present invention has an agitating blade attached at a specific interval and station to the spiral of at least the first toner conveying screw. capacity and the toner circulation ability of the two toner transport screws work synergistically,
It is possible to supply toner with extremely high charging stability to the photoreceptor drum.

Therefore, a copying machine equipped with the developing device of the present invention has no risk of contaminating the main body or peripheral parts with toner, and the quality of copied images is also excellent.

(Example) Hereinafter, the developing device Vi of the present invention will be described according to the drawings.

FIG. 1 is a cross-sectional explanatory view of a copying machine equipped with the phenomenon device of the present invention, FIG. 2 is a schematic structural view of FIG. 1, and FIG. 3 is a plan view of the phenomenon device of the present invention.

First, the developing device of the present invention is applied. For example, an overview of the configuration and functions of a copying machine will be explained with reference to FIGS. 1 and 2.

In FIG. 1, on the upper surface of the copying machine main body 11, there is provided a document loading table 12 which moves reciprocally along with the copying process, and at the center of the main body 11, there is provided a document table 12 which moves back and forth along with the copy process. A photoreceptor 13 serving as a drum-shaped developing portion that rotates in synchronization with the photoreceptor 13 is pivotally supported.

A lamp 13 is provided between the photoreceptor 13 and the original table 12.
．． Lens 14. An exposure unit 16 consisting of a mirror 15 and the like is provided to irradiate the document placed on the document table 12 and guide the reflected light onto the photoreceptor 13 to form an image of the document.

Further, around the photoreceptor 13, from this image formation position, the photoreceptor 1
3, the developing device 17 and the transfer device 1
8. Peeling device 19. Static eliminator 20° cleaning device 21. A static eliminating lamp 22 and a charging device 23 are arranged.

Further, a transfer path 24 for transfer paper P passing between the photoreceptor 13, the transfer device 18, and the peeling device 19 is provided in the main body 11, and the base end thereof is connected to a manual feed guide 25 provided on one side of the main body 11. Alternatively, a paper feed device 27 that independently feeds paper from the paper feed cassette 26 has its end facing a paper discharge tray 29 via a fixing device 28 .

Furthermore, as shown in FIG. 2, the main body 11 can be separated into an upper unit 30 and a lower unit 31 with the transfer path 24 as a boundary. One end of the upper unit 30 is rotatably supported by the lower unit 31, so that the upper unit 30 can be opened and closed.

First, an electrostatic latent image corresponding to the original is formed on the photoreceptor 13 by the charging device 23J3 and the exposure device 16.

Next, this electrostatic latent image is developed by applying toner T by the developing device 17, thereby forming a developer image on the photoreceptor 13.

This developer image is transferred to the transfer paper P fed by the paper feeding device 27.
The transfer paper P to which this developer image has been transferred is peeled off from the photoreceptor 13 by a peeling III device 19, and then the developer image is fixed by a fixing device 28.
The paper is discharged to the paper discharge tray 29.

On the other hand, the toner T remaining on the photoreceptor 13 without being transferred onto the transfer paper P is statically removed by S! The photoreceptor 13 is neutralized by the cleaning device 21 and the toner T is removed.
The static electricity is eliminated by the static elimination lamp 22, and the next process begins.

The phenomenon device 17 of the present invention in the copying machine is [
- Toner supply port 171 and first toner transport screw 1
72, a second toner conveyance screw 173, and a partition wall 17 separating these toner conveyance screws 172 and 173.
6 and a magnetic sleeve 174 are provided in a case 175, which is similar to the conventional developing device shown in FIG. are different.

That is, the first toner conveying screw 172 and the second toner conveying screw 173 are provided with spirals 172A and 173A facing in opposite directions, respectively, but in the phenomenon device 17 of the present invention, the first toner conveying screw Stirring blades 177 are attached above and below the spiral 172A of the screw 172 at opposing positions every two pitches with a phase shift, thereby improving the toner stirring ability.

Here, if the stirring blades are attached to all pitches of the spiral, although the toner stirring ability is improved, the toner circulation ability is conversely reduced, which is not preferable.

Furthermore, if the stirring blades are mounted opposite each other in each bit of the spiral, the phase between the stirring blades will be lost, and the toner will be trapped in that part, which will reduce the circulation ability, which is not preferable.

If the stirring blades are installed in the same phase, even if it is roughly or every two pitches of the spiral, the result will be the above 1.
This is not preferable because it is similar to the case for each pitch, and the circulation ability decreases.

On the other hand, as shown in the figure, at opposite positions every two pitches of the spiral of the first toner conveying screw 172,
In the developing device of the present invention, in which the stirring blades 177 are installed above and below with a phase shift, pitches where the stirring blades 177 are present and pitches where the stirring blades 177 are not present are alternately continuous, so that the ability to stir toner and developer is improved. Since it has been strengthened and still maintains its original circulation ability, it exhibits excellent stirring and circulation ability.

Although FIG. 3 shows an embodiment in which the stirring blade 177 is attached only to the first toner conveying screw 172, an am stirring blade may be attached to the second toner conveying screw 173 depending on the case.

However, in order to increase the ability to stir the toner supplied from the toner supply port 171, a stirring blade 177 is attached to the first toner conveying screw 172.

Therefore, the toner supplied to the developing device 17 of the present invention is
First, the toner is not stirred by the first toner conveyance screw 172 and then transferred from A to B. After passing over the partition wall 176, the toner is further stirred by the second toner conveyance screw 173 and then transferred from A to A. This cycle is then repeated.

Therefore, the toner is uniformly charged in the stirring/fl ring and stably supplied to the circumferential surface of the magnetic sleeve 174, thereby completely eliminating the possibility that the toner will fly to the periphery.

``Effects of the Invention: In the developing device of the present invention, stirring blades are attached to at least the spiral of the first toner conveying screw at specific intervals and arrangement, so that the stirring ability and circulation ability of toner and developer are equalized. It is possible to supply uniformly and stably charged toner to the magnetic sleeve.

Therefore, in the developing device of the present invention, there is no risk of toner scattering and contaminating the main body of the device or surrounding parts, and a copy image of excellent quality can be obtained.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional explanatory view of a copying machine equipped with the developing device of the present invention, FIG. 2 is a structural schematic diagram of FIG. 1, FIG. 3 is a plan view of the developing device of the present invention, and FIG. 1 is a perspective view of a conventional developing device. 11... Copying machine main body 17... Developing device 171... Toner supply port 172... First toner i feeding screw 172A...
・Spiral 173...Second toner conveying screw 173A...
・Spiral 174... Magnet sleeve 175... Case 176... Partition wall 177... Stirring blade

Claims (2)

[Claims] (1) A toner supply port, a first toner transport screw that stirs the supplied toner and transports it in the longitudinal direction, a second toner transport screw that stirs the toner and transports it in the opposite direction, and agitation. What is claimed is: 1. A developing device comprising a magnetic sleeve for transferring the toner to a photoreceptor drum, the developing device comprising a stirring blade attached to at least the first toner conveying screw. (2) At least the stirring blades are placed at opposing positions every two spiral pitches in the first toner conveying screw,
A developing device according to claim (1), characterized in that the developing device is installed with a phase shift.