JPH03249781A - Developer leakage preventing device and process cartridge provided therewith - Google Patents

Abstract

PURPOSE:To prevent toner from leaking from a gap by overlapping on end seal and a longitudinal direction seal. CONSTITUTION:An interference part 25a with a sleeve lower seal 24 and an interference part 25b with a regulating blade 23 are provided up and down with respect to the end seal 25, and the sleeve lower seal 24 and the sleeve end seal 25 are overlapped, then the seal 24 are interposed by the part 25a and a sleeve 21. Thus, the gap between the sleeve end seal 25 and the sleeve lower seal 24 is eliminated, thereby preventing the toner from leaking from the gap.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a developer leak prevention technology for image forming apparatuses using electrostatic latent images such as electrophotography, such as copying machines and laser printers. .

[Prior Art] The conventional technology will be explained by taking as an example a small laser printer used as an output device of an information processing system. 7th
As shown in the figure, a laser printer 1 has an image forming apparatus main body 2.
The process cartridge 3 includes an electrophotographic photosensitive drum 4 as an image carrier, a charger 5, a developer 6, and a cleaner 7 disposed around the electrophotographic photosensitive drum 4. It has built-in known process equipment such as Further, a scanner unit 8 and a mirror 9 for irradiating and scanning laser light are arranged on the upper part of the apparatus main body 2, and a latent image corresponding to predetermined image information is placed on the photosensitive drum 4, which is uniformly charged by the charger 5. An image is formed, and the latent image is developed by a developing device 6 to become a toner image. Further, a paper feed cassette 10 for storing a large number of sheet materials S is arranged below the main body 2 of the apparatus, and a paper feed roller 11 is arranged facing the paper feed cassette 10. The sheet materials S housed in are fed one by one to the registration rollers 12 by the paper feed roller 11, and are sent between the photosensitive drum 4 and the transfer charger 13 at the same timing by the registration rollers 12. , the toner image on the photosensitive drum 4 is transferred at this position. and,
The sheet material S onto which the toner image has been transferred is sent to the fixing device 15 by the conveyor belt unit 14, the toner image is fixed thereon, and the sheet material S is discharged out of the apparatus main body 2.

For maintenance of the laser printer 1, ie, jam removal, replacement of the process cartridge 3, etc., the upper part 2a of the main body 2 of the apparatus should be replaced with the lower part 2, as shown by the two-dot chain line in the figure.
This is done by rotating upwards about the support shaft P relative to b to open the inside of the device, and inserting the hand from the direction of arrow A.

Here, FIG. 4(A) is a perspective view of the conventional developing device 6, FIG. 4(B) is a sectional view at section A in FIG. 4(A), and FIG. 4(C) is a perspective view of the conventional developing device 6. FIG. 4 is a sectional view taken at section B in FIG. 4(A).

The container 17 containing the toner 20 of the developing device 6 includes a developing sleeve 21 that rotates and transports the charged toner 20 to the photosensitive drum 4, a magnet roller 22 that magnetically attracts the toner 20 to the sleeve 21, and a magnet roller 22 that is directed toward the photosensitive drum. a metal plate that is in gentle contact with the developing sleeve along its longitudinal direction in order to regulate the amount of toner 20 conveyed to the developing sleeve;
An elastic blade 23 made of rubber or the like is provided.

Reference numeral 24 denotes a sleeve lower seal, which seals the toner 2 in the container 17.
0 is inserted into the container 17 to prevent it from flying out from under the developing sleeve 21), and the developing sleeve 21 is rotated in the direction of the arrow in FIG. 4(B) along its longitudinal direction. It is an elastic film made of polyethylene terephthalate or the like that is in gentle contact.

Reference numeral 25 denotes a sleeve end seal, which is fitted in the container 17 to prevent the toner 20 from flying out from the longitudinal end of the developing sleeve 21, as shown in FIG. 4(C). An elastic member such as felt or maltblane that is compressed to seal its longitudinal ends.

[Problem to be Solved by the Invention] However, as shown in FIG. 5, between the sleeve end seals 25 at both ends 11! It is difficult to fit the sleeve lower seal 24 (length ρ2) without a gap in J21 (development width). It is difficult to eliminate the gaps ΔJ2L and ΔJZR due to processing dimensions, molding dimensions, and assembly work. Further, this also applies to the relationship between the developer layer thickness regulating blade 23 and the sleeve end seal 25. Therefore, as shown in FIG. 6, the toner 20 tends to leak from the gap.

[Means for Solving the Problems] The developer leakage prevention device of the present invention includes a first seal member that comes into contact with a longitudinal end of a developer carrying member that carries and transports developer to prevent developer leakage. , a second member that abuts along the longitudinal direction of the developer carrying member to prevent leakage of the developer.
Since the first seal member and the second seal member are overlapped with each other, leakage of the developer from the boundary between the first seal member and the second seal member can be prevented. When applied to the developing device of the present invention, the developer carrying member is a member that carries and conveys the developer to the developing section, such as a developing roller or sleeve, and when applied to a cleaning device, the developer carrying member is a member such as a photosensitive drum that is transferred. This is an image carrier that carries the remaining developed image and conveys it to the cleaning section.

[Examples] Examples of the present invention will be described below. Figure 4 (A)
, (B), and (C) are given the same reference numerals, and their explanation will be omitted unless necessary.

FIG. 1(A) shows a first embodiment of the present invention, and FIG.
B) is an exploded view of the sleeve end seal 25.

For the conventional end seal 25, as shown in FIG. 1(B), an interference part 25a with the sleeve lower seal 24 or an interference part 25b with the regulation blade 23 is provided above and below the end seal 25, and a second
As shown in the figure, the lower sleeve seal 24 and the sleeve end sleeve 25 are overlapped, and the seal 24 is sandwiched between the portion 25a and the sleeve 21. (The same applies to the regulating blade 23, so the explanation will be omitted below.) As a result, the gaps △ILL and △ρ3 shown in FIG.
This prevents toner from leaking from the gap (Fig. 6).

[Other Embodiments] On the other hand, FIG. 3 shows another embodiment of the present invention, and FIG. 3 (A
) is a perspective view thereof, and FIG. 3(B) is a sectional view at part 0 in FIG. 3(A). The waste toner 26 remaining without being transferred on the photosensitive drum 4 rotating in the direction of the arrow in the figure is scraped off by an elastic cleaning blade 27 pressed against the drum 4 and stored in a container 18 of the cleaner 7.

Here, the cleaner 7 is equipped with a cleaner end seal 28 that contacts the longitudinal end of the tram 4, a lower cleaner seal 29 that contacts the drum 4 along the longitudinal direction, and a cleaning blade 27. It has a structure similar to that of the developing device 6 of 2005, and prevents toner from leaking. At this time, the ends of the cleaner lower seal 29 and the cleaner end seal 28 are overlapped in the same manner as described above to eliminate the gap, thereby preventing the toner 20 from leaking. Similarly, the cleaning plate 27 and the cleaner end seal 28 can be used to remove the toner 20 without any gaps due to overlap.
leakage can be prevented.

[Effects of the Invention] As explained above, in the toner seal of a developing sleeve or photosensitive drum that rotates with developer applied thereto, leakage of developer can be prevented by overlapping the end seal and the longitudinal seal. be able to.

By preventing developer leakage, the process cartridge can be kept clean and the user's handling can be improved.

[Brief explanation of drawings]

FIG. 1(A) is an external perspective view of an embodiment of the present invention, FIG. 1(B) is a perspective view of an end seal member, FIG. 2 is a perspective view of essential parts of an embodiment of the present invention, and FIG. 3(A) is an external perspective view of another embodiment of the present invention, FIG. 3(B) is a sectional view, FIG. 4(A) is an external perspective view of a conventional example, and FIG. 4(B), ( C) is a sectional view, FIG. 5 is a perspective view of a seal portion of a conventional example, FIG. 6 is an explanatory diagram of developer leakage, and FIG. 7 is an explanatory diagram of a process cartridge to which the present invention can be applied. 3 is a process cartridge, 4 is a photoreceptor, 6 is a developing device,
7 is a cleaner; 21 is a sleeve; 23 is a regulating blade; 24 is a lower seal; 25 is an end seal; 27 is a cleaning blade; 28 is an end seal; 29 is a lower seal. 25a 2zoη

Claims (2)

[Claims] (1) A first seal member that contacts the longitudinal end of the developer carrying member that carries and conveys the developer to prevent leakage of the developer; and a first seal member that contacts the longitudinal end of the developer carrying member to carry out development. A developer leakage prevention device comprising: a second seal member for preventing developer leakage; the first seal member and the second seal member are overlapped with each other; (2) A process cartridge that is equipped with a developer carrying member that carries and conveys developer and is removable from the main body of an image forming apparatus, and that comes into contact with the longitudinal end of the developer carrying member to prevent leakage of the developer. and a second seal member that contacts along the longitudinal direction of the developer carrying member to prevent leakage of the developer, and the first seal member and the second seal member are overlapped. A process cartridge equipped with a developer leakage prevention device.