JP4420639B2 - Toner conveying apparatus, electrophotographic apparatus and cleaning apparatus using the same - Google Patents

Description

  The present invention relates to a toner conveying device of an image forming apparatus such as a copying machine, a printer, and a facsimile using an electrophotographic process, and an image forming apparatus and a cleaning device using the toner conveying device.

  2. Description of the Related Art Conventionally, various means have been developed for a toner conveying device used in a developing device of an image forming apparatus such as a copying machine, a printer, and a facsimile machine, and the toner conveying performance has been improved.

FIG. 10 is a perspective view showing a first example of a conventional toner conveying means. FIG. 11 is an enlarged view of a main part showing a second example of a conventional toner conveying means. Conventionally, there are a conveying screw 31 (FIG. 10) and an auger 32 (FIG. 11) as conveying means in the toner conveying apparatus.
However, since the axes pass through the center of these, only conveyance in the linear direction is possible, and there are many layout restrictions. Further, when it is impossible with a single conveying screw or auger, a plurality of the toners are conveyed in combination.
In this case, driving means are required for each of them, resulting in an increase in cost, and a problem such as toner clogging is likely to occur due to a failure in toner transfer at each joint.
FIG. 12 is an explanatory view showing a third example of a conventional toner conveying means. FIG. 13 is an explanatory view showing a fourth example of a conventional toner conveying means. A spring coil 33 as shown in FIG. 12 and an auger coil 34 as shown in FIG. 13 are used to solve the above problems.
Since there is no central axis, these can be arranged even in a curved conveyance path. As a result, the layout margin is increased and the sheet can be conveyed by a single coil, so the cost is low. However, these have poor toner conveyance performance. This is because the spring coil is a wire and has a low toner conveying capability.
Compared with the spring coil 33, the auger coil 34 shown in FIG. 13 also has a higher conveying ability because of its wider toner conveying surface, but since there is no central axis, the toner escapes to the part where there is no central auger, and the toner is conveyed. It is easy to get stuck.
In recent years, when it is required to reduce the size of the apparatus, the toner transport path may need to be transported not only downward and horizontally but also obliquely upward. Conventionally, the toner is difficult to be conveyed in the obliquely upward conveying portion, and problems such as insufficient toner supply and coil locking are likely to occur.
SUMMARY OF THE INVENTION Accordingly, a first object of the present invention is to solve the above problems by preventing toner from being concentrated and solidified when transporting toner, thereby realizing smooth toner transport, space-saving and inexpensive transport. An object of the present invention is to provide a high-performance toner transport device using a transport coil.
The second object of the present invention is to prevent the toner from being concentrated and solidified when transporting the toner even when using a toner by polymerization to improve the image quality, and to realize smooth toner transport. An object of the present invention is to provide an image forming apparatus that uses a low-cost toner conveying device in a space.
A third object of the present invention is to provide a toner for transporting toner even when waste toner mixed with paper dust or waste toner generated from a mechanism using zinc stearate as an assist for cleaning a photoreceptor is used. It is an object of the present invention to provide a cleaning device that can prevent toner density and solidification, realize smooth toner conveyance, and use a low-cost and low-cost toner conveyance device.

In order to solve the above-mentioned problem, in the invention according to claim 1, the narrow band plate-like flat plate surface is formed in a coil shape so as to become a toner conveying surface, and is rotated from one end side to the other end side. In the toner conveying device having a helical coil auger that conveys toner to the side of the part, the flat plate surface viewed from an axial cut surface including the axis of the flat plate of the helical coil auger is in contact with the axis of the toner. A toner transport device that is inclined at an obtuse angle toward the downstream side in the transport direction is the main feature.
In the second aspect of the present invention, an electrophotographic apparatus using a toner conveying device as claimed in claim 1, wherein the feature.
In the third aspect of the present invention, an electrophotographic apparatus according to claim 2, wherein the toner is a toner made of polymerization and feature.
In the invention of claim 4, wherein a waste toner wherein the toner is generated in the electrophotographic apparatus, according to claim 2 or 3, wherein the waste toner generated from the mechanism using zinc stearate as an aid to the photoconductor cleaning the electrophotographic apparatus and Features.
In the invention of claim 5, wherein the cleaning device toner conveying device according to claim 1, wherein is configured as a process cartridge and feature.

According to the first aspect of the present invention , the angle of the flat plate of the coil auger is inclined at an obtuse angle toward the downstream side of the toner conveyance direction with respect to the axis, so that the auger is reliably and efficiently between the wall of the casing. Since toner is transported, toner can be prevented from being concentrated and solidified, smooth toner transport can be realized, and transport performance is good, so it can be transported in an obliquely upward direction, and it is space-saving and low-cost. realizable.
According to the second aspect, since the conveyance performance is good, the conveyance in the obliquely upward direction can be efficiently performed, the layout margin of the toner conveyance path is increased, the size can be reduced, and a special processing technique is required. Therefore, the cost can be reduced, and the electrophotographic apparatus can be reduced in size and cost.
According to the third aspect of the present invention, since the toner produced by the polymerization method has the same particle size for each toner particle and is small, it easily aggregates, but smooth toner conveyance can be realized.
According to the fourth aspect of the present invention, waste toner mixed with paper dust and waste toner generated from a mechanism using zinc stearate as an aid for photoconductor cleaning have a high degree of aggregation and poor fluidity, but smooth toner conveyance. Can be realized.
According to the fifth aspect, in the case of a process cartridge, when an abnormality occurs in one of the components included in the process cartridge, it is necessary to replace the entire cartridge, and the components that are still in service life are discarded. Although not economical, this configuration can prevent problems such as crowding and solidification of waste toner when the transfer residual toner from the photosensitive drum is transported as waste toner, and the advantages of the process cartridge (good Workability).

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a front view showing an electrophotographic apparatus using the toner conveying apparatus of the present invention. The photosensitive drum unit 3 is exposed from the writing unit 1 to form a latent image. It is developed by the developing unit 4 and transferred to paper by the transfer unit 5. After the transfer, the image is fixed by the fixing unit 13 and then discharged outside the apparatus.
The electrophotographic apparatus A shown in FIG. 1 is a full-color printer, and includes four photosensitive drum units 3 (black: K, yellow: Y, cyan: C, magenta: M) and four developing units 4.
FIG. 2 is a front sectional view of the photosensitive drum unit. FIG. 3 is a perspective view of the photosensitive drum unit of FIG. The photosensitive drum unit 3 includes a photosensitive drum 17, a charging roller 18, a charging roller cleaner 19, a cleaning blade 20, a cleaning brush 21, and a waste toner transport coil 22.
In each photosensitive drum unit 3, the untransferred toner on the photosensitive drum 17 is collected by the cleaning blade 20 and the cleaning brush 21. The cleaning brush 21 sends the collected untransferred toner to the waste toner conveying coil 22 side. Further, the waste toner is conveyed from the front of the unit to the waste toner discharge port 23 on the back side by the rotation of the coil.
FIG. 4 is a perspective view showing the vicinity of the waste toner conveyance path disposed on the rear side plate of the electrophotographic apparatus main body. The waste toner discharged from the waste toner discharge port 23 of the photosensitive drum unit 3 falls to the corresponding waste toner recovery port, is transported by the transport coil through the waste toner recovery path, and is stored in the waste toner bottle.
In order to reduce the size of the electrophotographic apparatus in order to reduce the size of the electrophotographic apparatus, the waste toner path is curved at various places as shown in the figure so as to be disposed at a portion that does not interfere with other units, and there is a portion that is conveyed obliquely upward.

FIG. 5 is an explanatory view showing a coil auger according to the present invention. The helical coil auger 35 of the present invention shown in FIG. 5 has a flat plate surface of a narrow band-shaped body constituting the auger inclined by 90 ° or more with respect to the axis with respect to a conventional coil auger (FIG. 13).
FIG. 6 is an explanatory view showing another example (comparative example) of the coil auger of the present invention. The helical coil auger 36 of the comparative example shown in FIG. 6 is inclined by 90 ° (75 °) or less with respect to the axis of the flat plate surface of the narrow strip forming the auger with respect to the conventional coil auger (FIG. 13). ing.
FIG. 7 is a schematic diagram showing the relationship between a conventional coil auger (FIG. 13) and waste toner as a comparative example. FIG. 8 is a schematic diagram showing the relationship between the coil auger (FIG. 5) of the present invention and waste toner. FIG. 9 is a schematic diagram showing the relationship between the coil auger (FIG. 6) of the present invention and waste toner.
As a result, as shown in FIGS. 7 and 8, the waste toner spills and stays in the central portion where there is no coil in the conventional case (FIG. 7), whereas in the present invention shown in FIG. In the spiral coil auger 35, waste toner is conveyed while being pressed in the direction of the wall of the case. Therefore, a large amount of waste toner can be conveyed at a time, and the conveyance performance is improved. This has actually been confirmed by trial manufacture.
However, conversely, as shown in FIGS. 6 and 9, when the flat surface of the helical coil auger 36 is 90 ° or less with respect to the axis, the conveyance performance is worse than the conventional 90 °, and it accumulates in the central portion without the coil. The amount of toner is also increasing.
Waste toner mixed with paper dust or a mechanism that uses zinc stearate as an aid to photoconductor cleaning (a mechanism that applies zinc stearate to the surface of the photoconductor) is used. However, according to the present invention, smooth toner conveyance can be realized. In other words, even when using a cleaning mechanism that uses zinc stearate, it is possible to prevent toner from becoming dense and solidified when transporting toner, and to achieve smooth toner transport, using a space-saving and low-cost toner transport device. A cleaning device can be provided.

By constructing an electrophotographic apparatus such as a copying machine, a printer, or a facsimile apparatus using the toner conveying apparatus of the present invention, a stable toner conveying property can be obtained. Since the conveyance performance is good, it is possible to efficiently convey in an obliquely upward direction, increasing the layout margin of the toner conveyance path, realizing downsizing, and realizing low cost because it does not require so much special processing technology. This makes it possible to reduce the size and cost of the electrophotographic apparatus.
It is also effective to use a toner made by a polymerization method as the toner. That is, the toner produced by the polymerization method has a uniform particle size for each toner particle and is small, so that it easily aggregates, but smooth toner conveyance can be realized.
It is also effective to configure the toner conveying device as a process cartridge. In the case of a process cartridge, if an abnormality occurs in one of its components, it is necessary to replace the entire cartridge, and the parts that are still in service are discarded. By adopting the configuration of the present invention, it is possible to prevent problems such as crowding and solidification of waste toner when transporting the transfer residual toner from the photosensitive drum as waste toner, and to obtain the advantages (good workability) of the process cartridge. You can save it.

1 is a front view showing an electrophotographic apparatus using a toner conveying device of the present invention. FIG. 3 is a front sectional view of the photosensitive drum unit. FIG. 3 is a perspective view of the photosensitive drum unit in FIG. 2. FIG. 3 is a perspective view showing the vicinity of a waste toner conveyance path disposed on a rear side plate of an electrophotographic apparatus main body. Explanatory drawing which shows the coil auger by this invention. Explanatory drawing which shows the other example of the coil auger of this invention. FIG. 14 is a schematic diagram showing a relationship between a conventional coil auger (FIG. 13) and waste toner as a comparison. FIG. 6 is a schematic diagram showing a relationship between a coil auger (FIG. 5) of the present invention and waste toner. FIG. 7 is a schematic diagram showing a relationship between a coil auger (FIG. 6) of the present invention and waste toner. FIG. 6 is an explanatory diagram illustrating a first example of a conventional toner conveying unit. Explanatory drawing which shows the 2nd example of the conventional toner conveyance means. Explanatory drawing which shows the 3rd example of the conventional toner conveyance means. Explanatory drawing which shows the 4th example of the conventional toner conveyance means.

Explanation of symbols

35 spiral coil auger

Claims (5)

In a toner conveying apparatus having a helical coil auger that is formed in a coil shape so that a flat plate surface of a narrow band plate becomes a toner conveying surface and rotates to convey toner from one end side to the other end side The toner is characterized in that the flat plate surface viewed from the axial cut surface including the axis of the helical coil auger is inclined at an obtuse angle toward the downstream side in the toner transport direction with respect to the axis. Conveying device.   An electrophotographic apparatus using the toner conveying apparatus according to claim 1. 3. The electrophotographic apparatus according to claim 2, wherein the toner is a toner made by a polymerization method. 4. The electrophotographic apparatus according to claim 2, wherein the toner is a waste toner generated in the electrophotographic apparatus, and is a waste toner generated from a mechanism using zinc stearate as an auxiliary for cleaning the photoreceptor. .   The cleaning apparatus according to claim 1, wherein the toner conveying apparatus is configured as a process cartridge.

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