JP2003162149A - Powder storing container, developing device equipped therewith and electrophotographic image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a powder storing container capable of restraining the tilt of the driving shaft of a rotating member while restraining the longitudinal width of the powder storing container and stably keeping sealing property by a seal member. <P>SOLUTION: A toner container in which toner is stored is provided with a toner stirring member 303 capable of rotating in a container main body, a toner stirring gear 313 fit on a circular tube-like projection part 320 formed around a container hole part 322 and transmitting driving force to the member 303, and an oil seal 314 sealing the hole part 322. The gear 313 is fit on a fitting surface 326 at the outside diameter part of the projection part 320, and the seal 314 is fit on a fitting part 327 at the inside diameter part of the projection part 320, then the fitting surfaces 326 and 327 are positioned to be superposed in the radial direction of the rotation of the member 303. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a powder container for containing powder such as toner, a developing device having the same, and an electrophotographic image forming apparatus.

Here, the electrophotographic image forming apparatus forms an image on a recording medium by using an electrophotographic image forming system. Then, examples of the electrophotographic image forming apparatus include, for example, an electrophotographic copying machine, an electrophotographic printer (for example, a laser beam printer, an LED printer, etc.), a facsimile machine, a word processor, and the like.

The powder storage container is a container for storing a developer used in an electrophotographic image forming apparatus or a waste developer remaining after being used for development.

[0004]

2. Description of the Related Art An electrophotographic image forming apparatus supplies a developer in a powder container to an electrophotographic photosensitive member to form a toner image, but conventionally, the powder in the powder container is agitated and conveyed. In order to drive the above-mentioned member, an opening is provided in the powder container, and a driving force from the outside of the powder container is transmitted to the stirring and conveying member inside the powder container through a drive shaft. The drive shaft is passed through the opening of the powder container, and the gap created in this part is typically sealed with a seal member such as an oil seal to prevent the powder from leaking to the outside. Was there.

Conventionally, a gear has been generally used for transmitting power to the drive shaft, but in this case, the meshing force of the gear causes a force to act in the direction in which the drive shaft falls. And
When the drive shaft falls, the interference amount (intrusion amount) between the drive shaft and the oil seal cannot be kept constant, so that the sealing property becomes unstable and there is a risk that the powder will leak to the outside. For this reason, a method has been adopted in which the fitting length A (see FIG. 7) between the powder container and the drive shaft is set to a certain length to prevent the drive shaft from tilting and the sealing performance is kept stable.

[0006]

However, in the above structure, if the fitting length between the powder storage container and the drive shaft is to be increased, the overall length of the powder storage container including the drive shaft also increases. Therefore, as a result, it is necessary to increase the longitudinal width of the image forming apparatus main body in which the powder container is mounted. For this reason, the entire apparatus becomes large, which is disadvantageous in terms of cost.

The present invention solves the above-mentioned problems.
The purpose is to suppress the tilt of the drive shaft of the rotating member while suppressing the longitudinal width of the powder container, and to stably maintain the sealing performance of the seal member, and a developing container including the powder container. An apparatus and an electrophotographic image forming apparatus are provided.

[0008]

A typical structure according to the present invention for achieving the above object is a powder container for storing powder in a container body, wherein the rotating member is rotatable in the container body. A drive transmission member for fitting a circular tubular projection formed around the opening of the container body to transmit a driving force to the rotating member, and a seal member for sealing the opening. , The drive transmission member is fitted to a first fitting portion in an outer diameter portion of the circular tubular projection portion, and the sealing member is fitted to a second fitting portion in an inner diameter portion of the circular tubular projection portion,
Further, the first fitting portion and the second fitting portion are positioned so as to overlap each other in the rotation radius direction of the rotating member.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] FIG. 1 is a longitudinal sectional view showing a schematic configuration of a four-color full-color laser beam printer which is an electrophotographic image forming apparatus embodying the present invention.

{Outline of image forming operation of color image forming apparatus} The photosensitive drum 1 which is an electrophotographic photosensitive member is rotated in the direction of the arrow (counterclockwise) in FIG. 1 in synchronization with the rotation of the intermediate transfer belt 5a. The surface of the photosensitive drum 1 is a charging device 2
Is uniformly charged, and the exposure unit 3 irradiates a yellow image with light to form a yellow electrostatic latent image on the photosensitive drum 1. Simultaneously with the formation of the electrostatic latent image, the developing device 4 is driven to position the yellow developing device 4Y at the developing position, and the photosensitive drum 1 is charged so that the yellow toner adheres to the electrostatic latent image on the photosensitive drum 1. A yellow toner is applied to the electrostatic latent image by applying a voltage having the same polarity and substantially the same potential to develop the electrostatic latent image. After that, a voltage having a polarity opposite to that of the toner is applied to the pressing roller (primary transfer roller) 5j of the intermediate transfer member 5 to primarily transfer the yellow toner image on the photosensitive drum 1 onto the intermediate transfer belt 5a.

When the primary transfer of the yellow toner image is completed as described above, the next developing device is rotationally moved and positioned at the developing position opposite to the photosensitive drum 1, and the magenta color is obtained in the same manner as in the yellow case. Electrostatic latent image formation for each color of cyan, cyan, and black
Development by M, 4C, and 4BK and primary transfer are sequentially performed, and toner images of four colors are superposed on the intermediate transfer belt 5a.

During this time, the secondary transfer roller 11 is not in contact with the intermediate transfer belt 5a. At this time, the charging roller 5f as a cleaning unit is also connected to the intermediate transfer belt 5a.
Is in non-contact with.

After the formation of the four color toner images on the intermediate transfer belt 5a, the secondary transfer roller 11 is pressed against the intermediate transfer belt 5a (the state shown in FIG. 1), and the intermediate transfer belt 5 is further pressed.
In synchronism with the rotation of a, the transfer material S that has been fed from the transfer material cassette 19 by the pickup roller 18 or the conveyance roller 20 as a feeding means and has been waiting at a predetermined position near the registration roller pair 7d is an intermediate transfer. It is sent out to the nip portion between the belt 5a and the secondary transfer roller 11.

Immediately before the registration roller pair 7d, a pre-registration sensor 14 that detects the leading end of the transfer material S to shut off the rotational driving force of the registration roller pair 7d and waits the transfer material S at a predetermined position. It is provided.

Further, a voltage having a polarity opposite to that of the toner is applied to the secondary transfer roller 11, so that the toner image on the intermediate transfer belt 5a is transferred to the surface of the transfer material S which has been collectively conveyed.
Next transfer.

The transfer material S secondarily transferred in this manner
Reaches the fixing device 8 via the conveyor belt unit 12, where the toner images of a plurality of colors are fixed, and then the discharge roller pair
The sheet is conveyed along the discharge guide 15 by the discharge roller pair 13, and is discharged by the discharge roller pair 9 on the discharge tray 10 above the color image forming apparatus A
And the image formation is completed.

On the other hand, after the secondary transfer, the cleaning charging roller 5f is pressed against the intermediate transfer belt 5a to give the residual toner remaining on the intermediate transfer belt an electric charge opposite to that at the time of transfer.

The residual toner to which the opposite charge is applied is electrostatically attached to the photosensitive drum 1 and then collected by the cleaning blade 6 for the photosensitive drum.

The collected residual toner follows a conveyance path for conveying the waste toner, which will be described later, and is collected and accumulated in the waste toner container 16.

{Developing device} The developing device 4 includes four developing devices capable of developing each color of yellow, magenta, cyan, and black in order to visualize the electrostatic latent image on the photosensitive drum 1. It is composed of vessels 4Y, 4M, 4C and 4Bk.

As shown in FIG. 1, the developing devices 4Y, 4M, 4C, and 4Bk are detachably held by a rotary unit 301 that rotates about an axis, and at the time of image formation, the developing devices 4Y, 4M. , 4C and 4Bk are held by the rotary unit 301, rotate about an axis, and a predetermined developing device stops at a position facing the photosensitive drum 1, and a developing roller 305, which is a toner carrier, described later.
Is positioned so as to contact the photosensitive drum 1, and then a visible image is formed corresponding to the electrostatic latent image on the photosensitive drum 1.

During color image formation, the intermediate transfer belt 5
The rotary unit 301 rotates once for each rotation of a, and the developing process is performed in the order of the yellow developing device 4Y, the magenta developing device 4M, the cyan developing device 4C, and then the black developing device 4Bk.

The color developing devices 4Y, 4M, 4C, and 4Bk are different in the colors of the toners stored therein, but have the same structure. FIG. 2 is a cross-sectional explanatory view of one developing device 4. The developing device 4 sends the toner in the toner container 302, which is the main body of the powder container, to the toner supply roller 304 by the toner stirring member 303, which is a rotating member, and rotates the toner supply roller 304 in the clockwise direction in FIG. The developing blade 332 pressed against the outer circumference of the roller 305 applies a thin layer of toner to the outer circumference of the developing roller 305 rotating clockwise in FIG. 2 and imparts electric charge to the toner (friction charging).

By applying a developing bias to the developing roller 305 facing the photosensitive drum 1 on which the latent image is formed, toner development is performed on the photosensitive drum 1 according to the latent image. Magenta developing device 4M, cyan developing device 4
With respect to C and the black developing device 4Bk, toner development is performed by the same mechanism as described above.

Further, each developing roller 305 of each developing device 4Y, 4M, 4C, 4Bk is provided with a high voltage power source and drive (not shown) for developing each color provided in the printer main body when each developing device is rotationally moved to the developing position. ), And a drive is connected by sequentially applying a voltage selectively for each color development.

{Toner stirring means} Next, in the developing device 4,
A drive transmission path to the toner stirring member 303 will be described.

FIG. 3 is an external view of the developing device 4. The drive input gear 306 of the developing device 4 receives a drive input from a gear on the image forming apparatus side (not shown), and drives the above-described developing roller 305, toner supply roller 304, and toner stirring member 303.

FIG. 4 is an exploded perspective view of the drive gear train, and FIG. 5 is a layout explanatory view of the gear train. As shown in the figure, the developing drive input gear 306 is a stepped gear, and one of them transmits the drive to a gear unit 307 that receives a driving input from a gear of the image forming apparatus, a developing roller gear 309, and a toner supply roller gear 310. It consists of a gear unit 308. Then, the developing roller gear 309
Drive is transmitted from the step gear to the idler gear 311 and the idler gear 312, and finally, the toner stirring gear 31 which is the drive transmission member.
Drive is transmitted to 3.

(Toner Stirring Gear Mounting Structure) Next, the mounting structure of the toner stirring gear 313 will be described with reference to FIG.

An oil seal 314, which is a sealing member, is fitted into the toner container 302 in advance. The toner stirring gear 313 has a gear portion to which driving force is transmitted and a shaft portion integrated with the gear portion.
With the toner agitation gear 313 attached to 02, the shaft portion of the toner agitation gear 313 is a hole 3 which is an opening in which the oil seal 314 is fitted from the outside.
It is fitted into the toner stirring member 303 through 22. here,
The toner stirring member 303 is a resin-molded toner stirring shaft 315.
In addition, a stirring sheet 316, which is a sheet member made of PET, for example, having a thickness of about 0.1 mm is joined.

As shown in FIG. 7, the toner stirring shaft 315 has a hole 317 into which the toner stirring gear 313 is fitted, and the shaft portion of the toner stirring gear 313 is passed through this hole. Also,
To prevent the toner agitating gear 313 from coming out of the fitted state, the hole 317 of the toner agitating shaft 313 is provided with a lateral hole 31.
8 is provided, and the elastically deformable claw portion 319 of the toner agitating gear 313 is inserted therein, and serves to prevent the toner agitating gear 313 from coming off. As shown in FIG. 6, the toner container 302 is composed of two members. After the toner stirring member 303 and the toner stirring gear 313 are assembled, the toner bottom member 340 is joined to form the toner container 302.

(Toner stirring gear and toner container fitting part)
Next, the fitting relationship between the toner stirring gear 313 and the toner container 302 in the conventional product will be described with reference to FIG.

The toner container 302 has a cylindrical projection 320 for fitting and supporting an oil seal 314 and a toner stirring gear 313.
Is provided. First, the oil seal 314 is fitted into the inner diameter portion 321 of the circular cylindrical protrusion 320. And
The toner stirring gear 313 is fitted so as to pass through the hole 322 formed in the circular cylindrical protrusion 320 so as to pass through the shaft. Here, the fitting portion 323 of the toner stirring gear 313 is fitted with the inner diameter portion 330 of the circular tubular protrusion 320 of the toner container 302. Further, the shaft portion 324 of the toner stirring gear 313 and the lip portion 325 of the oil seal 314 are
It has a certain amount of intrusion (closeness), and at this part, the lip portion 325 of the oil seal 314 clamps and seals the shaft portion 324 of the toner stirring gear, so that the toner inside the toner container 302 does not leak out. I try not to.

Since the fitting portion 323 of the toner stirring gear and the position of the oil seal 314 are apart from each other in the axial direction of the toner stirring gear 313, as shown in FIG.
Due to the looseness (gap) between the 313 and the toner container 302, the shaft tilt of the toner stirring gear 313 is amplified at the seal portion of the oil seal 314 that is in contact with the toner stirring gear 313. That is, the value of α shown in FIG. 9 increases as the distance from the fitting portion between the shaft 328 and the hole 329 increases. In order to suppress the fluctuation of the amount of invasion (interference) between the toner stirring gear shaft portion 324 and the oil seal lip portion 325 due to the shaft tilting, the fitting length A between the toner stirring gear 313 and the toner container 302 is set to be long to some extent. The shaft of the toner stirring gear 313 can be prevented from tilting.

Next, the fitting relationship between the toner stirring gear 313 and the toner container 302, which is characteristic of this embodiment and is different from the conventional product, will be described with reference to FIG.

In this embodiment, the toner stirring gear 31
3 is not the inner diameter of the circular tubular protrusion 320 of the toner container 302,
It is fitted to the outer diameter portion 331. As a result, it is not necessary to dispose the fitting portion 323 of the toner stirring gear 313 and the oil seal 314 in the axial direction, and the fitting surface (first fitting portion) 326 of the toner stirring gear 313 and the toner container 302 is eliminated. And oil seal 314
The fitting portion between the toner container 302 and the toner container 302 can be brought close to each other.
That is, the fitting surface 326 between the toner stirring gear 313 and the circular tubular projection 302 and the fitting surface (second fitting portion) 327 between the oil seal 314 and the circular tubular projection 320 are the radial direction of the fitting surface. That is, they are positioned so as to overlap with each other in the radial direction of rotation of the toner stirring shaft 315. FIG. 8B shows a range in which the fitting surfaces overlap with each other at a portion B. If the mating surfaces are arranged in this relationship,
It is possible to prevent the value of α shown in FIG. 9 from increasing as the distance between the shaft 328 and the fitting portion of the hole 329 increases. Therefore, the oil seal lip portion 325 and the toner stirring gear shaft portion 324
At the contact position with the toner stirring gear 313 compared to the conventional configuration
It is possible to prevent the shaft from tilting, secure a stable interference, and maintain the sealing property. Further, as a result, the fitting length A between the toner stirring gear 313 and the toner container 302 can be made shorter than in the conventional configuration, and the fitting surface 326 is arranged further inside the toner container 302. , The overall width of the device can be suppressed,
The cost of the device can be reduced.

[Second Embodiment] The present invention can be used not only in the toner container of the developing device shown in the first embodiment, but also in a waste toner container for storing the waste toner remaining after the developing process. .

10 and 11 are explanatory views showing the structure of the waste toner container. The waste toner is stored in the waste toner container 16 in the order described below. The waste toner remaining after development on the photosensitive drum 1 is scraped off by the cleaning blade 6 and stored in the cleaning container 16. The waste toner is first sent backward by the feed spring 151 in the cleaning container 16 and then conveyed by the screw 28 in the axial direction of the photosensitive drum 1. When the waste toner carried by the carrying of the screw 28 is sent to the end of the screw 28, it is then sent to the screw 158 by the impeller 155. Finally, the waste toner is sent to and stored in the waste toner container 16 by the screw 158.

The screw 28, the screw 158, and the impeller 155 are driven by the gear train 31, 163, 164 shown in FIG. The drive gear shafts that drive each drive the waste toner container 16
Screw 28, screw 15 through the hole drilled in
8. Engage the impeller 155 to transmit the driving force. The gap between each drive gear shaft and the hole of the waste toner container 16 is set so that the waste toner does not leak to the outside as in the case of the developing device.
It is sealed by an oil seal 314 which is a seal member.

Also in this case, as in the case of the first embodiment described above, the waste toner container 16 is provided with the cylindrical seal 320 for fitting and supporting the oil seal 314 and the drive gear shaft, and the drive gear shaft is provided. Is fitted to the outer diameter portion of the circular tubular protrusion 320, and the oil seal 314 is fitted to the inner diameter portion thereof. By doing so, the fitting width between the drive gear shaft and the waste toner container 16 can be reduced, and the tilting of the drive gear shaft can be suppressed sufficiently, and a stable interference with the oil seal 314 can be ensured and sealing performance can be improved. It becomes possible to maintain.

As described above, the drive gear shaft and the waste toner container 16
Reducing the fitting width of (1) reduces the longitudinal width of the cleaning device, and further suppresses the longitudinal width of the entire image forming apparatus, thus making it possible to reduce the cost of the apparatus.

[0042]

As described above, according to the present invention, the longitudinal width of the powder container is suppressed, the tilting of the drive shaft of the stirring and conveying member is suppressed, and the seal between the powder container and the drive shaft is suppressed. It is possible to provide a powder container and an electrophotographic image forming apparatus in which the sealing property of a member is stably maintained and the powder does not leak to the outside and contaminate.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an electrophotographic image forming apparatus.

FIG. 2 is a sectional view of a developing cartridge.

FIG. 3 is a perspective view of a developing cartridge.

FIG. 4 is an assembly diagram of a gear train of a developing cartridge.

FIG. 5 is a layout view of a gear train of the developing cartridge.

FIG. 6 is an assembled perspective view of a developer stirring member.

FIG. 7 is a cross-sectional view showing a fitting relationship between a conventional developer stirring gear and a developer container.

FIG. 8 is a cross-sectional view showing a fitting relationship between a developer stirring gear of the present invention and a developer container.

FIG. 9 is a view showing a tilted state of the shaft when the shaft and the hole are fitted together.

FIG. 10 is a sectional view of a cleaning unit.

FIG. 11 is a sectional view showing a waste toner conveying member of the waste toner container.

[Explanation of symbols]

A ... Color image forming apparatus S ... Transfer material 1 ... Photosensitive drum (electrophotographic photosensitive member) 2 ... Charging device 3 ... Exposure means 4 ... Developer 4Bk ... Black developing device 4C: Cyan developing device 4M ... Magenta developer 4Y ... Yellow developing device 5 ... Intermediate transfer member 5a ... Intermediate transfer belt 5f ... Charging roller 5j ... Presser roller 6 ... Cleaning blade 7d ... Registration roller pair 8… Fixer 9 ... Ejection roller pair 10… Ejection tray 11… Secondary transfer roller 12… Conveyor belt unit 13… Ejection roller pair 14… Sensor before cash register 15… Discharge guide 16… Waste toner container 18… Pickup roller 19… Transfer material cassette 20… Conveyor roller 28… screw 151… Spring 155 ... impeller 158… screws 301… Rotary unit 302… Toner container (powder container body) 303 Toner stirring member (rotating member) 304 Toner supply roller 305 ... Developing roller (toner carrier) 306… Drive input gear 307 ... Gear section 308 ... Gear section 309 ... Development roller gear 310 Toner supply roller gear 311 ... Idler Gear 312… Idler Gear 313 ... Toner stirring gear (drive transmission member) 314 ... Oil seal (seal member) 315 ... Toner stirring shaft 316… Stirring sheet 317 ... hole 318… Horizontal hole 319… Claw section 320 ... Protrusion 321… Inner diameter 322… Hole (opening) 323… Mating part 324… Shaft 325… Lip part 326… Mating surface (first fitting part) 327 ... Fitting part (second fitting part) 328… Axis 329 ... hole 330 ... Inner diameter 331 ... Outer diameter 332 ... Development blade 340 ... Container bottom member

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yasushi Yoshino             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation F-term (reference) 2H077 AA12 AB01 AB03 AB13 AC04                       AD06 BA02 BA08 CA13 GA13

Claims (5)

[Claims] 1. A powder storage container for storing powder in a container body, comprising: a rotatable member rotatable within the container body; and a circular tubular protrusion formed around an opening of the container body, A drive transmission member for transmitting a drive force to the rotating member; and a seal member that seals the opening, the drive transmission member being a first fitting portion in an outer diameter portion of the circular tubular protrusion. The seal member is fitted to the second fitting portion in the inner diameter portion of the circular cylindrical protrusion portion, and
The powder container according to claim 1, wherein the fitting portion and the second fitting portion are positioned so as to overlap each other in the rotation radius direction of the rotating member. 2. The powder according to claim 1, wherein the drive transmission member has a gear portion and a shaft portion, and the shaft portion is inserted from the opening portion and engages with the rotating member. Storage container. 3. The powder container according to claim 2, wherein the sealing member seals a gap between the opening and the shaft portion inserted from the opening. 4. A developing device for supplying toner, which is powder, to an electrophotographic photosensitive member, and a toner container for storing the toner, and the toner contained in the toner container is supplied to the electrophotographic photosensitive member. A developing device, comprising: a toner carrying member for storing the toner; and the powder container according to any one of claims 1 to 3 as the toner container. 5. An image forming apparatus for forming a latent image on an electrophotographic photoreceptor and developing the latent image with a developing device to form an image, wherein the developing device comprises the developing device according to claim 4. And an electrophotographic image forming apparatus.