JPS59136763A - Developer stirring device of developing machine - Google Patents

Abstract

PURPOSE:To mix and stir sufficiently toner and carrier by supplying the developer in the developing machine to the housing of the developing machine after mixing and stirring the developer in a room dedicated to conveyance and mixing. CONSTITUTION:The whole or part of the developer after being used for development in a development area is conveyed to the room 10 dedicated to conveyance and mixing by the 1st conveying means 7, and the developer in this room 10 is conveyed into the housing 2 of the developing machine A by the 2nd conveying means 8. Then, conveying/mixing blades 11 having blade plates 11b with opening parts 11c are provided freely rotatably in the room 10 dedicated to conveyance and mixing.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a developer stirring device for a developing machine that uses a two-component developer consisting of toner and carrier.

In a developing machine that uses a two-component developer consisting of toner and carrier, the mixing ratio and mixing state of toner and carrier have a large effect on image quality.

For example, if the toner density is uneven in the axial direction (that is, in the axial direction of the developing roll), the image on the photosensitive material becomes uneven in the axial direction, making it impossible to obtain a uniform copy.

Additionally, if the amount of toner in the developer suddenly increases due to variations in the amount of toner supplied to the developer, the toner and carrier will not be mixed sufficiently, and the toner with an insufficient amount of charge will be carried to the development area, causing the photosensitive material to deteriorate. It adheres to the background area and causes a fogging phenomenon on copies.

To this end, various types of stirring devices have been proposed to stir the toner and carrier, but they have not produced satisfactory results, and when replenishing toner, the amount of toner supplied must be made uniform in the axial direction. No means have been proposed which are complicated and which give fully satisfactory results.

In other words, in conventional developing machines, the developer after development is dropped directly into the housing of the developing machine, and toner is also supplied directly to the developer in the housing, making it difficult to mix and stir the toner and carrier. In addition, since uniformity in the axial direction is strictly required when toner is supplied, the above-mentioned problems occur.

The present invention has been made in view of the above circumstances, and its purpose is to transport the developer of the developing machine, mix it in a dedicated mixing chamber, stir it, and then transport it into the housing of the developing machine, so that one toner and carrier can be sufficiently mixed. To provide a developer stirring attachment for a developing machine which enables mixing and stirring.

The present invention will now be described in detail with reference to the drawings. FIG. 1 is a perspective view, in which a housing 2 of a developing machine A is provided facing a drum-shaped photosensitive material 1, and the housing 2 is approximately U.
A pair of developing rolls 3□ includes a bottom wall 2a curved in a character shape and a pair of side walls 2b covering openings on both sides thereof, and extending between the pair of side walls 2b.

32 and the conveyance paddle 4 are rotatably provided, and the scraping plate 5 is in contact with the 20th rule 32 and is continuous with the scraping plate 5 to form a U-shape and extend between the pair of side walls 2b. A groove 6 (that is, continuous in the axial direction of the developing roll 3) is formed, and the groove 6 opens outward from the opening 2'b of the side wall 2b. A first auger 7 serving as a means is provided rotatably over the longitudinal direction.

An M2 auger F3 serving as a second conveyance means is rotatably supported in the axial direction of the conveyance paddle 4, and
One end 8' of the auger 8 is connected to an opening 2 formed in the side wall 2b.
〃Protrudes outward from b.

9 is an auxiliary housing fixed to the side wall 2b;
Said 1st. The second auger 7.8 has a bottom wall 9a and a side wall 2b covering one end 7', 8' of the first auger 7.8.
A transport and mixing chamber IQ is formed at an intermediate position between the transport and mixing chamber IQ and the second auger end 8'.
A conveying and mixing blade 11 is rotatably provided inside the container 0.
Further, an auger 1 connected to the toner box 12 and serving as a replenishment toner conveying means is located above the first auger end 7'.
3 is coming.

Reference numeral 14 denotes an ear stand adjustment member.

In addition, 1. The second developing rolls 31 and 32 each have a sleeve 3b rotatably provided around a magnet 3a.

...The conveyance and mixing blade 11 described in I has a blade plate 1 attached to the rotating shaft 11a.
1b are fixed in a radial manner, and each blade plate 11b has an opening 11c.
The structure is made up of the following.

Thus, the developer that has been conveyed by the developing roll 3 and passed through the developing area A facing the photosensitive material 1 falls and accumulates in the groove 6 even if it is separated by the scraping plate 5.

The toner concentration in the developer in the groove 6 is lower than the toner concentration in the developer in the housing 2, and the toner concentration in the axial direction (developing roll axial direction) is non-uniform.

The developer in the groove 6 is mixed by the first auger 7 into the transport mixing chamber 1o while being transported and dropped.The developer is then transported and dropped from the auger 13 by the transport mixing blade 11 rotating in the transport mixing chamber 10. The toner is conveyed and supplied to one end 6' of the second auger g while being mixed with the supplementary toner.

The second auger 8 is conveyed by a conveyance mixing blade 11, and the supplied developer is further mixed by the mixing action of the auger and conveyed into the conveyance paddle 4. and is sequentially supplied to the developing roll 3.

The developer supplied to the developing roll 3 in the above manner always has a uniform toner concentration in the axial direction, and the toner and carrier are sufficiently mixed to maintain the toner in a normally charged state. .

Further, since the toner replenishing mechanism does not need to uniformly supply replenishing toner over the entire axial direction, the toner replenishing mechanism can be made simple and inexpensive.

Also, conveyance, mixed feathers! Since each blade plate 11b of A11 is formed with an opening 11c, the replenished toner passes through the opening 11c of the blade plate 11b or is rotated and conveyed in the portion of the blade plate 11b other than the opening 11c. Therefore, the toner and developer are sufficiently mixed.

Note that in the above embodiments, an auger is used to transport the developer.
Although the material is transported inside the mixing chamber 10 and the transport paddle 4, other transport means may be used, such as one using an inclined plate and a vibration effect, or one using an air flow.

Furthermore, the toner replenishment mechanism and toner replenishment position are not limited to those in the above embodiment; they may be the same as those in the prior art.

According to the present invention, as described above, the toner and carrier can be sufficiently mixed and stirred to obtain a sufficient amount of charge, so that good development can be performed without toner adhesion to the background part of the photosensitive material. Inside, the replenishment toner and the developer can be sufficiently mixed by the conveyance mixing blade 11, and even better development can be performed.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of the present invention, and FIG. 2 is a cross-sectional view of an auxiliary housing portion. 1 is a photosensitive material, 2 is a housing, 3 is a developing roll, 6 is a groove, 7 and 8 are first . The second conveyance means, 1° is the conveyance mixing room, 11F! Conveying mixing blade, ++b is a blade plate, Ilc is an opening. Applicant Fuji Xerox Co., Ltd. Agent Patent Attorney Masaaki Yonehara Patent Attorney Tadashi Hamamoto

Claims (1)

[Claims] All or part of the developer that has passed through the development area and has been used for development is transported by the first transport means 7 to the dedicated mixing chamber 10, and the developer in the dedicated transport and mixing chamber 10 is transferred to the second The conveying means 8 is used to convey into the housing 2 of the developing machine A, and a conveying/mixing blade 11 having a vane plate 11b having an opening llc is rotatably provided in the conveying/mixing chamber 10. A developer stirring device for a developing machine characterized by: