JPS5912465A - Developing device - Google Patents

Abstract

PURPOSE:To prevent environmental contamination caused by a residual developer, by arranging a number of independent guide pieces in the lengthwise direction of a cartridge at intervals at a cartridge storing hollow part on a developing device side where the cartridge is inserted, extracted, and rotated. CONSTITUTION:A number of guide pieces 71, 72, 73-7n, and 81, 82, 83-8n are arranged at adequate intervals in the cartridge lengthwise direction at the cartridge storing hollow part on te developing device side where the cartridge 2 is inserted, extracted extracted, and rotated. Consequently, when a developer in the catridge is supplied to a development position, almost all of a developer falling out of an opening 2a falls out from gaps formed between guide pieces 71 and 72, and 81 and 82, and it never resides on the outer circumferential surface of the cartridge, so that the environmental contamination caused by the residual developer is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Object of the Invention The present invention relates to a developing device in an image forming apparatus such as a copying machine or an electrostatic printer.

In the above-mentioned image forming apparatus, various methods have conventionally been used to supply developer to the developing device.As illustrated in FIG. The developer is stored in the cartridge 2, and the opening 2ai formed in the cartridge is inserted into the hollow cylindrical part provided in the developing device while keeping the opening 2ai horizontal. The opening 2a of the cartridge is engaged with the guide groove 5 formed in the hollow cylindrical portion.
i Hold it on the ground, disengage the protrusion 4 and groove 5 at a predetermined position, and rotate the cartridge 2 by approximately 180 degrees to form the opening 2a'jz of the cartridge 2 on the lower side of the cylindrical part 5. Conventionally, there has been known a structure in which the developer in the cartridge is caused to fall and be supplied into the entire developing device 1 in alignment with the opening 5a.

Such products have become increasingly popular in recent years, especially with the spread of one-component developers, as there is little risk of the operator touching the powdered developer or scattering it around the equipment. It is becoming more and more common.

However, as a practical matter, even with the developer supply mechanism as described above, it has not been possible to sufficiently prevent all of this unwanted escape of the developer. To briefly describe this with reference to FIGS. 2A and 2E, the cartridge 2 containing the developer shown in FIG. 2 is a cross-sectional view showing the insertion of the cartridge 2 into the hollow cylindrical portion 5, and the operation is performed smoothly when the cartridge 2 is inserted into the hollow cylindrical portion 5.
For this reason, when the cartridge 2 is stopped at a fixed position within the cylindrical portion 6, a gap as shown by the symbol G in FIG. 2A is created between the two, and this gap Naturally, this is extremely large compared to the menarche of powdered developer.

If the cartridge 2 is rotated in the direction indicated by the arrow in this state, the opening 2a of the cartridge 2 will move to the position shown in FIG. 2B before matching with the opening a of the cylinder part B. At this time, the internal developer escapes into the gap G. Of course, as the cartridge 2 further rotates, most of the developer 1 in the gap G falls into the developing device (from the opening 5a); When the cartridge is removed from the developing device, the portion remains attached to its outer wall surface Q and is taken out to the outside.

Anything that adheres to the outer surface of the cartridge can stain the operator's body, clothes, etc., or spill into the equipment, making it difficult to handle. Further, when the entire cartridge is taken out, the flange portion on the back side tends to scrape out the developer remaining on the inner wall surface of the hollow cylinder portion 6 of the developing device, which also causes environmental pollution.

In order to eliminate all of these drawbacks, for example, a flexible material such as felt or maltbrene is attached to the insertion opening edge of the hollow cylinder portion 5 on the developing device side, which is the front end of the cartridge, to provide a cleaning effect when the cartridge is pulled out. Although some proposals have been made to make the cleaning process more difficult, there was a risk that the felt itself would rapidly become contaminated as the cartridges were repeatedly inserted and removed, not only degrading the cleaning effect but also having the opposite effect. .

Furthermore, the cylindrical portion 6 on the side of the IJ full developing device
As the cartridge is repeatedly inserted, the developer remaining on the inner wall surface of the cylindrical portion is squeezed out by the corner of the tip of the cartridge, and as the cartridge is pushed in, it is transported toward the back of the cylindrical portion and compacted. If this gradually accumulated, it could interfere with the smooth operation of the cartridge.

The present invention is based on the above-mentioned construction, and the present invention is completely different from the present invention.
In particular, the cartridge housing side wall portion corresponding to the hollow tube WJ6 shown in FIG.

At least in the lower half, a large number of independent guide pieces are formed along the longitudinal direction of the cartridge, thereby allowing the entire cartridge to be smoothly inserted and removed, and rotating the cartridge in order to drop and supply the developer into the entire developing device. By allowing all of the developer that escapes to fall through the gap formed between the guide pieces, even if the cartridge is inserted and removed, some developer remains inside and this developer is removed. The object of the present invention is to provide a developing device in which there is no risk of the liquid being exposed to the outside when the cartridge is pulled out or being attached to the outer surface of the cartridge and contaminating the surrounding area. : An example of the present invention will be described.

(→Structure of the Invention Fig. 5 is a perspective view showing a part of a developing device equipped with a cartridge insertion/removal section according to the present invention, and the hollow cylindrical elongated hole portion for inserting/ejecting the cartridge has a roughly semicircular cross section. Only the lower half of the cylindrical upper half is shown with the entire upper half removed.

As the cartridge, a known cartridge having a generally cylindrical shape as shown in FIG. 1 is used, and this cartridge is inserted into the developing device from the direction of arrow B in the figure. In this case, a groove corresponding to the guide groove 5 on the developing device side, which is provided on the cartridge and is engaged with the protrusion 4, is formed in the semicircular cylindrical portion of the upper half not shown in FIG. As a result, the cartridge is inserted while being maintained over the entire opening 2a, and the flange at the front end of the cartridge is positioned in close contact with the front end surface of the developing device, and further,
In this position, the groove and the protrusion are disengaged and the car
It is no different from any known device in that it can be rotated freely in this position.

In such a device, in the present invention, a large number of guide pieces 71, 72, 74...7n are provided at least in the lower half of the cartridge insertion hole as shown in FIG.
2, 83, . . . 8n are formed with appropriate spacing between them.

The surface of each guide piece is formed into an arc shape, which is a part or whole of the cylindrical surface, so that the cartridge can be freely inserted and removed.

(C) Since the structure is as shown in Akane Akira's purpose, after inserting the cartridge 2 in the direction of arrow B in FIG. The developer is rotated about 1800 times until the part still contacts the stopper pin 9 on the developing device side, and held below the opening 2ai to supply all the developer in the cartridge to the developing device. 71. The guide piece almost falls on the developer.
The gaps f' formed between 72, 81, 82, and so on do not spill over and remain near the outer peripheral surface of the cartridge. In addition, when the cartridge is pulled out, the corners of each guide piece 71...81... are squeezed and come into contact with each other and are displaced relative to each other when the cartridge is pulled out. As the developer falls inside the device (C), residual developer adheres to the surface of the cartridge and comes out.

It is also possible to reliably prevent residual developer from being scraped out of the developing device by the rear edge of the cartridge.

Naori - Since the guide pieces that guide the cartridge when inserting and removing the cartridge are not continuous, the distance between the guide pieces should be selected so that the distance between the guide pieces is not too large so that the insertion operation of the cartridge does not become smooth. is necessary. In order to completely smooth the insertion of the cartridge, for example, as shown in FIG. 4A (this figure is an enlarged view of the deformation of the part corresponding to the part surrounded by the two-dot chain line in FIG. 6), Guide piece 7
2', 73', etc., it is convenient to form the top in a full circular arc shape, and by forming it in this way, there is no flat part where residual developer tends to accumulate, so that the developer further accelerates falling. This is suitable because it reduces the Furthermore, the fourth
As shown in Figure B, the guide piece 72''.

A similar effect can be obtained by forming a te-no-ku or chamfer on both sides like 73"+7).

FIG. 5 shows the deformation of the guide pieces, in which the entire surface of each guide piece 71, 72...81, 82, on which the cartridge 2 is placed, has an L-shaped arc. A continuous curved surface (or curved line) is made up of a part of the curved surface and portions 71a, 81a, etc., which are formed so that the lower part of the curved line is straight or has a large radius of curvature. This structure not only accelerates the fall of the developer, but also prevents the entire cartridge from rubbing in this area, causing the developer to move as the cartridge changes. Since the amount is further reduced, it becomes more effective in preventing contamination.

FIG. 6 shows another embodiment of the present invention.
Instead of arranging a large number of guide pieces as shown in the figure, a relatively small number of guide pieces are provided, and the long gaps between the guide pieces fit into a part of the cylindrical surface sufficient to allow the cartridge to pass through. Trim the mesh 10 to create an arc surface that looks like this.
a, 10b'i.

Even in such a configuration, the same effects as in the embodiment shown in FIG. 6 can be expected, and it is easy to understand that the configuration shown in FIG. 5 can be applied. By the way.

[Brief explanation of drawings]

FIG. 1 is a schematic perspective view showing a known cylindrical cartridge and the operation of a developing device using the same, FIGS. 2 A and B are sectional views of the same essential parts, and FIG. 4A and 4B, and FIG. 5 are enlarged slope views and end views showing modified examples of the guide piece. FIG. 6 is a perspective view of essential parts showing another embodiment of the present invention. 1.6...Developing device, 2...Cartridge, 2
a...Opening, 6...Hollow cylindrical portion, 4...Protrusion FIB, 5...Guiding groove, 71.72...7
n, 81°82...82n...guide piece, 9
...Stock bottle, 10a, 10b - Net material Fig. 3

Claims (1)

[Scope of Claims] In a developing device for an image forming apparatus in which all cartridges containing all developer are installed and the cartridges are rotated to fully replenish the developer, the side of the developing device where the cartridges are inserted and removed and rotated. A developing device comprising a plurality of independent guide pieces spaced apart from each other at least in a lower half of the hollow portion along the longitudinal direction of the cartridge in a hollow portion for housing the cartridge.