JPS5912464A - Developing device - Google Patents

Abstract

PURPOSE:To prevent the accumulation and solidification of toner, by forming a gap between the innermost end surface of a cartridge and the facing surface of a developing device side which faces it, and forming a communication part which communicates with a developer bank part to accelerate the falling of a developer. CONSTITUTION:The developing device is so constituted that when the cartridge is stopped in a specific position in the developing device, the gap T is formed between the innermost end surface of the cartridge 2 and the facing surface 6a of the developing device side. Further, a slanting surface 6b for accelerating the falling of toner to the toner bank part under the developing device is formed under said facing surface 6a and communicates with the toner reservoir part. Consequently, toner is never accumulated and caked at the innermost part of a cartridge insertion hole to cause trouble in the operation of the cartridge and developing operation.

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 been conventionally used to supply developer to the developing device.As illustrated in FIG. The i! which houses the developer and maintains the opening 2a formed therein upwards! It is inserted into the hollow cylinder part provided in the developing device, and the above-mentioned car is inserted until it reaches the specified position.
The protrusion 4 provided on the J edge 2 is engaged with the guide groove 5 formed in the hollow cylinder on the developing device side to hold the opening 2a of the cartridge upward, and the protrusion 4 and the recess are held at a predetermined position. Disengage the groove 5 and move the cartridge approximately 180 degrees.
Conventionally, there has been known a structure in which the developer in the cartridge is caused to fall and be supplied into the developing device 1 by rotating the opening 2a of the cartridge 2 to match the opening 3a formed on the lower side of the cylindrical portion 6. It is being

Such materials are considered less likely to cause the operator to come into direct contact with the powdered developer or to be scattered around the equipment.
With the spread of one-component developers, they have become increasingly popular in recent years.

However, as a practical matter, even with the developer supply mechanism as described above, it has not been possible to sufficiently prevent this unwanted escape of the developer. To briefly explain this with reference to FIGS. 2A and 2B, FIG. 2A shows the cartridge 2 containing the developer being inserted into the hollow cylinder part B of the developing device 1 while keeping its opening 2a upward. is a cross-sectional view showing the inner diameter of the hollow cylindrical part 6 compared to the outer diameter of the cartridge 2 so that the operation can be performed smoothly when inserting the cartridge 2 into the hollow cylindrical part 6. Therefore, when the cartridge 2 is stopped at a fixed position in the cylindrical filter, a gap as shown by the symbol G in FIG. Naturally, it is extremely large compared to the powder diameter of the developer.

In this state, if the cartridge 2 is rotated in the direction of the arrow A, the opening 2a of the cartridge 2 will assume the position shown in FIG. 2B before matching with the opening 3a of the cylinder 6. , at this time, the internal developer escapes into the gap G. Of course, as the cartridge 2 moves further, most of the developer in the gap G falls into the developing device from the opening 3a, but some of it remains attached to the inner wall of the hollow cylinder, and the other part remains. When the cartridge is taken out from the developing device, it is taken out to the outside while remaining attached to the outer wall surface of the cartridge.

Materials adhering to the outer wall of the cartridge may stain the operator's body, clothing, etc., or may spread inside the device and stain it, making it difficult to handle. Further, when taking out the cartridge, there is a tendency to scrape out the developer remaining on the inner wall surface of the hollow cylindrical portion 6 of the developing device, either on the flange portion on the back side of the scoop, and this also causes environmental pollution.

In order to solve this problem, for example, a flexible material such as felt or maltbrene is attached to the insertion opening edge of the hollow cylinder part 6 on the side of the developing device into which the cartridge is inserted, so that it has a cleaning effect when the cartridge is pulled out. Although some proposals have been made to reduce the number of cartridges, there was a risk that the repeated insertion and removal of cartridges would rapidly contaminate the felt itself, deteriorating the cleaning action, and even have the opposite effect. .

Furthermore, as the cartridge is repeatedly inserted into the cylindrical part B on the developing device side, the developer remaining on the inner wall surface of the cylindrical part is squeezed out by the corner of the tip of the IJ screw, and the cartridge is pushed. As the cartridge is inserted, it is conveyed and compacted in the direction of the cylindrical part, and if this gradually accumulates, there is a risk that it will interfere with the smooth operation of the cartridge. In order to prevent this drawback, a method has been proposed in which the innermost part of the developing device is opened and the tip of the IJ screw protrudes outside, but it is difficult to process the extruded developer after engraving. However, they were careful not to contaminate the inside of the plane.

The present invention has been developed in view of the above-mentioned current situation, and in particular, the cartridge is inserted into the developing device, and the large diameter flange portion of the front end of the cartridge is marked, and stops when it comes into contact with the side of the developing device. When the toner inside the cartridge is in a fixed position where it can fall into the developing device, a gap is formed between the end of the cartridge and the opposite surface of the developing device, and the developing device By configuring the opposing surface on the side to communicate with the toner storage section in the device, toner accumulates in the innermost part of the cartridge insertion hole of the developing device due to repeated loading and unloading of the cartridge as described above. The toner may solidify and interfere with cartridge operation and development, or when the cartridge is installed or removed, this toner may remain attached to the front end of the cartridge and be drawn out, staining the equipment, operator's clothes, body, etc. The purpose of this invention is to provide a developing device that does not exist in the prior art.

(B) Structure of the Invention FIG. 6 is a perspective view showing a part of a developing device equipped with a cartridge insertion/removal section according to the invention, and the hollow cylindrical elongated hole portion into which the cartridge is inserted/removed has a cross section. Only the lower half of the semi-cylindrical upper half is shown.

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, the four parts corresponding to the guide grooves 5 on the developing device side, which are engaged with the protrusions 4 provided on the cartridge, are provided in the semicircular cylindrical part of the upper half not shown in FIG. As a result, the cartridge is inserted with the opening 2a held upward, and the flange at the front end of the cartridge is positioned in contact with the front end surface of the developing device. The cartridge is rotatable in this position, which is no different from any known device.

The cartridge insertion portion of the developing device B has a large number of guide pieces 71.72.73-.7n and 81.82.86.in at least the lower half of the cartridge insertion hole as shown in FIG.
- 8n are formed with appropriate spacing between them for sliding. The upper surface of each guide piece is formed in an arc shape forming a part of a cylindrical surface through which a cartridge can be freely inserted and removed, and the opening 2a is maintained upward in the direction of arrow B in FIG. After inserting the cartridge 2 to the internal position of the developing device, the cartridge 2 is rotated approximately 180 degrees until the protrusion comes into contact with the stopper pin 9 on the developing device side, and the opening 2a is brought downward, and the developing device inside the cartridge is inserted. When supplying the volatile agent to the developing device, most of the developer that spills from the opening 2a during rotation falls through the gaps formed between the guide pieces 71, 72, 81, 82, etc., and spills onto the outer peripheral surface of the cartridge. It will not remain in the vicinity. In addition, when the cartridge is pulled out, the corners of the guide pieces 71, 81, and so on are displaced relative to each other while pulling out the cartridge. Since the developer falls into the cartridge, it is possible to reliably prevent residual developer from being scraped out from the cartridge surface, or from being scraped out by the rear edge of the cartridge to the outside of the developing device. It is possible.

Guide when inserting and removing the cartridge Since the valley guide pieces move continuously, the distance between the guide pieces should not be too large so that the cartridge insertion operation does not move smoothly. It is desirable to select

In the present invention, as shown in FIG. 3, when the cartridge stops at the internal position of the developing device, the outermost end surface of the cartridge 2 and the corresponding developing device Between the opposing surface 6a on the side (is the gap T
Further, a slope 6b is formed below the opposing surface 6a to promote the toner falling into the toner storage section at the bottom of the development device. It is communicated.

(c) Effects of the invention The present invention is generally configured as described above, and the card
Even if the cartridge is repeatedly inserted and removed from the developing device, the toner mostly falls through the gaps formed between the guide pieces 71, 81, and so on, so that the toner does not fall between the facing surface 6a and the rear end surface of the cartridge. There is little possibility of accumulation on the slope 6, and the presence of the gap T and the slope 6
As a result of the formation of b, all of the toner immediately falls into the toner reservoir, so there is no accumulation. Of course, this conveying action can be similarly achieved in the case of a known developing device as shown in FIG. 1. In this case, a large number of independent guide pieces as shown in FIG. It is easy to understand that the effect is much more pronounced than if it were the case. Of course, this slope can also be formed vertically on substantially the same plane as the opposing surface 6a.

[Brief explanation of drawings]

FIG. 1 is a schematic perspective view showing the operation of a known cylindrical cartridge and a developing device using the same, FIGS. 2 A and B are sectional views of essential parts of the same, and FIG. FIG. 1.6...Developing device, 2...Cartridge 2a...Opening, 3...Hollow cylinder portion 4/Kist protrusion, 5...Guiding groove 6a...Opposing surface, 6b...Slope 71, 72. Fist 70 81.82...8n...Guide piece 9 Fist/Stopper bottle, T...Gap Applicant Canon Co., Ltd. 1 Figure 1

Claims (1)

[Scope of Claims] In a developing device in which a cartridge containing a developer is inserted and the cartridge is positioned at a fixed position to replenish the developer, the innermost part of the cartridge at the fixed position in the developing device A developing device in which a gap is formed between an end face and a facing face on the side of a developing device facing thereto, and a communicating part with a developer reservoir is formed following the facing face to promote falling of the developer. Device.