JP3349563B2 - Developing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device for an image forming apparatus such as a copying machine, a facsimile, a printer, and more particularly to a developing device using a dry two-component developer.

[0002]

2. Description of the Related Art A dry two-component developer is mounted on an image forming apparatus such as a copying machine, a facsimile, a printer, or the like, and visualizes an electrostatic latent image formed on a photosensitive member by an electrostatic recording method. Are well known. In a conventional two-component developing device, a separator, a conveying screw, an agitator, and the like are used as a horizontal stirring member of the two-component developer, but a developing device of a type using both a separator and a conveying screw is widely used. ing.

Here, an example of this type of developing device will be described with reference to the drawings.

In FIG. 6, a developing device 11 mounted on an image forming apparatus is installed in proximity to a photosensitive drum 22. The developing device 11 includes a paddle 13 and a developing sleeve 1.
4, a doctor blade 12, a separator 15, a conveying screw 16 and the like, and a toner replenishing unit 20 is attached. The developer G in the developing device 11 is flipped up by the rotation of the paddle 13 and is
It is magnetized upward. The magnetized developer is regulated to a fixed amount by the doctor blade 12 and supplied to the photosensitive drum 21. The developer remaining due to the regulation of the doctor blade 12 is laterally stirred by the separator 15 and the conveying screw 16, and is
The toner is supplied to the paddle 13 after being mixed with the toner supplied from Step 1.

In the developing device constructed as described above, for example, when the developer is replaced at a regular inspection, the toner replenishing section 20 is detached from the developing device 11 and the top and bottom of the developing device 11 are moved as shown in FIG. Is turned upside down, and the developer G in the apparatus is discharged from the opening (toner supply section mounting port) 17.

[0006]

However, in the conventional developing device, when the developer in the device is discharged,
The separator 15 of the horizontal stirring member acts as a shielding member,
The work of collecting (discharging) the developer stored in the horizontal stirring member is not only difficult and troublesome, but also it is difficult to sufficiently collect (discharge) the developer. If a new developer is filled with the old developer remaining in the apparatus, and the image forming apparatus is used for development, the old developer (carrier) is added to the electrostatic latent image on the photoconductor. There is a problem that an abnormal phenomenon or an abnormal image occurs, such as adhesion of developer or the developer spilling out of the developing device.

The present invention solves the above-mentioned problem in a conventional developing device using both a separator and a conveying screw as a horizontal stirring member, and can reliably collect (discharge) the developer in a short time. The task is to provide

[0008]

SUMMARY OF THE INVENTION The object of the present invention is to provide a developing apparatus for an image forming apparatus using a dry two-component developer, which uses a separator and a conveying screw for stirring the developer. Wherein the separator comprises a frame portion and a skewing portion rotatably supported by the frame portion, and the skew portion rotates in the developer collecting direction when the developer in the apparatus is collected. Is done.

[0009]

Further, in order to solve the above-mentioned problem, the present invention proposes that the rotatable separator is fixed at a predetermined position in a state where the developing device is mounted on the image forming apparatus.

[0011]

The separator in the developing device comprises a frame portion and a skewing portion rotatably supported by the frame portion. When collecting the developer in the apparatus, the obliquely provided slidable portion rotates in the direction of collecting the developer (for example, the developer collection port is turned upside down with the top and bottom of the apparatus turned upside down). (If collecting, the sloping part rotates downward.)
By this, the separator does not hinder the recovery of the developer,
The developer can be quickly and reliably collected.

Other effects will be apparent from the following description of the embodiment.

[0013]

Embodiments of the present invention will be described below.

FIG. 1 is a side view showing an embodiment of the developing device according to the present invention, and shows a state in which the developing device 10 is installed close to a photoreceptor 22. Note that the toner supply section is omitted in FIG. Separator 1 of developing device 10
As shown in an enlarged view in FIG. 2, the main body part 1a surrounding the conveying screw 16 and a skewed part 1b for returning the developer regulated by the doctor blade 12 to the rear of the paddle are divided into two parts. It is configured. The skew portion 1b is rotatably attached to the frame portion 1a by a shaft 1c. Other configurations of the developing device 10 are the same as those of the conventional developing device 11 described with reference to FIG.

When the developing device 10 is mounted on the image forming apparatus, as shown in FIG. 1, the skewed portion 1b of the separator 1 is positioned so as to ride on the other end of the frame portion 1a and close the opening. ing.

In the developing device 10 of the present embodiment, when the developer in the device is discharged, the top and bottom of the developing device 10 are turned upside down as shown in FIG. I will release the developer inside. At this time,
As described above, since the skewed portion 1b of the separator 1 is rotatably attached to the skeleton portion 1a, the skewed portion 1b rotates counterclockwise in FIG. Is opened. Therefore, the developer G (see FIG. 2) stored in the horizontal stirring member is easily discharged from the developing device, and the developer in the device is easily collected (released).
can do.

As described above, since the skewed portion 1b of the separator 1 is rotatable, the skewed portion 1b is not fixed when the developing device 10 is mounted on the image forming apparatus as it is. If the developing device 10 is driven to perform an image forming operation in that state, the skewed portion 1b moves up and down due to vibration, and the reliable lateral stirring function is impaired. Then, there is a possibility that the bias of the developer occurs in the developing device 10, which leads to generation of an abnormal image such as unevenness of a solid black image.

For this reason, in this embodiment, as shown in FIG. 4, a separator pressing member 23 is provided near the toner supply roller 21 of the toner supply section 2. When the toner replenishing section 2 is attached to the developing device 10, as shown in FIG. 5, the separator pressing member 23 presses the skewed portion 1b of the separator 1, and even if the developing device 10 is mounted on the image forming apparatus, The portion 1b is fixed without rattling. Therefore, an abnormal phenomenon such as bias of the developer is suppressed, and an abnormal image is not generated.

[0019]

[0020]

[0021]

As described above, according to the developing device of the present invention, when the developer in the apparatus is collected, the skewed portion of the separator rotates in the direction of collecting the developer. Can collect (discharge) the developer in the apparatus easily and reliably without damming the developer.

[0022]

According to the second aspect of the present invention, when the developing device is mounted on the image forming apparatus, the skewed portion is fixed at a predetermined position. Therefore, it is possible to prevent the bias of the developer and secure a stable developer balance. it can.

[Brief description of the drawings]

FIG. 1 is a side view showing a state in which an embodiment of the developing device of the present invention is mounted on an image forming apparatus.

FIG. 2 is an enlarged view showing details of a separator of the developing device shown in FIG. 1;

FIG. 3 is a side view showing a state in which the developing device shown in FIG. 1 is turned upside down to collect a developer.

FIG. 4 is a side view illustrating a toner replenishing unit attached to the developing device illustrated in FIG. 1;

FIG. 5 is a side view illustrating the developing device in a state where the toner supply unit illustrated in FIG. 4 is attached.

FIG. 6 is a side view showing an example of a conventional developing device.

FIG. 7 is a side view illustrating a state of the developing device illustrated in FIG. 6 when the developer is collected.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 15 Separator 1a Body part 1b Skew part 2, 20 Toner replenishment part 10, 11 Developing device 12 Doctor blade 13 Paddle 14 Developing sleeve 16 Conveyor screw 22 Photoreceptor 23 Pressing member G Developer

Claims (2)

(57) [Claims] 1. A developing device of an image forming apparatus using a dry two-component developer, wherein a separator and a conveying screw are used in combination for stirring the developer. A developing device, comprising a skewed portion movably supported, wherein the skewed portion rotates in a developer collecting direction when the developer in the apparatus is collected. 2. The developing device according to claim 1, wherein the skewed portion is fixed at a predetermined position when the developing device is mounted on the image forming apparatus.