JPS6095559A - Developing device - Google Patents

Abstract

PURPOSE:To such surely the scattered developer by providing a suction port which opens to the upper stream side and down stream side in the moving direction of a supply member which supplies the developer to a part to be developed and sucks the scattered developer. CONSTITUTION:A bottom cover 11 which forms the 1st duct 10 for sucking the developer 4 scattered from the inside of a case 1 to the outside is disposed to the bottom of the case 1 and a suction port 12 is positioned to face a photosensitive drum 2 in the lower part of a developing region. An upper cover 12 for preventing the scattering of the developer 4 from a magnet roller 6 is attachably and detachably attached to the side plate of the case 1 in the upper part of the case 1. The 2nd duct 16 for sucking the scattered developer 4 is formed between the upper part of the cover 13 and a cover 17 and a suction port is positioned to face between the magnet roller 6 and the cover 17.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention is applicable to, for example, an electronic copying machine or a digital copying machine. The present invention relates to a developing device used in r-printers and the like.

[Technical background of the invention and its problems]

For example, a magnetic brush printer that converts electrostatic latent images formed by electric charges into electronic copiers, G-11 printers, etc. lj! 1 ton of equipment is used. This developing device forms a magnetic brush using a developer consisting of 111 + rear made of magnetic material that holds 1 to 1 and 2 which are the source of the image, and uses this magnetic brush to The image is visualized by stroking the photoreceptor drum holding the image to avoid adhesion of toner.

For this reason, dust such as toner and carrier particles scatters and falls before and after contacting the photoreceptor drum, contaminating the inside of the machine and causing an adverse effect on images. Therefore, conventionally, a device has been used to suck out the dust inside the machine. However, as shown in FIG. 1, in the conventional apparatus, dust scattered above the developing area facing the magnet roller d is sucked by ducts 1 to C formed by a cover b at the top of a container a. It has become. For this reason, although it is possible to suction the dust that has scattered upward, it is not possible to suction the dust that has scattered and fallen downward, and there is a problem in that it is difficult to prevent dirt from forming inside the body.

[Purpose of the invention]

The present invention has been made based on the above-mentioned circumstances, and an object thereof is to provide a developing device that can reliably suck up scattered developer.

[Summary of the invention]

In order to achieve the above-mentioned object, the present invention provides a container for storing one temporary agent in a developer (111V41) which supplies a developer while moving to a developing area and develops the developing area. The container is equipped with a supply member for supplying the developer in the container to the to-be-developed portion, and suction ports opening on the upstream and downstream sides of the supply member in the above-mentioned relative movement direction and sucking the scattered developer. What are the characteristics?

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described with reference to FIG. 2 and FIG. 7. 2. In FIG. 5, reference numeral 1 denotes a container with an opening 3 facing a photoreceptor drum 2, which rotates in a predetermined direction and serves as a printing medium. A developer 4 consisting of a developer 4, an agitator 5 for agitating the developer 4, and a developer 4 stirred by the agitator 5 is conveyed to transfer the toner in the developer 4 to the photosensitive drum 2. A magnet roller 6 serves as a supply member for supplying developer 4 through the magnet roller 6, a layer thickness regulating member 7 regulates the layer thickness of the developer 4 conveyed to the magnet roller 6, and a layer thickness regulating member 7 regulates the layer thickness of the developer 4 to be supplied through the magnet roller 6. A collection plate 8 for returning the waste developer 4 to the agitator 5, a concentration detector 9 for detecting the concentration of the developer 4, and the like are accommodated.

A bottom lid 1 is formed at the bottom of the container 1 to form a first duct 10 for sucking the developer 4 scattered from inside the container 1 to the outside.
1 is arranged, and this first duct 10 has its suction port 12
faces the photosensitive drum 2 below the developing area. Further, an upper lid 13 is disposed on the upper part of the container 1 to prevent the developer 4 from scattering from the magnetic roller 6, and is detachably attached to the side plates 14 and 15 of the container 1. Also, a second duct 16 is formed between the cover 17 and the upper part of the upper lid 13 to suck up the scattered developer 4, and the second duct 16 has its suction port 18 connected to the magnet roller 6. It is placed between it and the cover 17.

In addition, a screen wall 19 is provided in the first and second ducts 10 and 16 to sequentially narrow the gap from the front side to the rear side in order to equalize the suction efficiency in the axial direction.

In addition, there are blocks 2 on the inside of the side plates 14 and 15 of the container 1.
0.21 are arranged facing each other, and inside the block 20 on the rear side there is a third duct that communicates with the first ducts 1 to 10 of the bottom cover 11.
A duct 22 is formed.

The third duct 22 and the second duct 16 on the upper side 113 are connected to each other at a fourth duct 23 provided on the rear side of the container 1. Do not connect to a suction device.

The magnet roller 6 has a cylindrical developing sleeve 24.
and a magnet 25 installed inside the developing sleeve 24, which is rotatably held on the side plates 14 and 15 of the container 1.

The stirrer 5 is held on the side plate 14.15 of the magnetic roller 6 on the opposite side from the photosensitive drum 2, and has two double spirals coaxially arranged with different winding directions.
These are partitioned by a cylindrical sleeve 26 to form an integral structure.

5- Also, a first gear 2 is attached to the shaft 27 of the developing sleeve 24.
8, second gears 30 are respectively attached to the shaft 29 of the stirrer 5, and these are connected and meshed via a third gear 31. The second gear 30 is a coupling gear, and is provided with an engaging protrusion 32.

The layer thickness regulating member 7 is approximately 30 mm thicker than the magnetic roller 6.
It is placed at the top. And block 2 on both sides
0.21, and by moving it horizontally, the layer thickness of the magnetic brush formed on the developing sleeve 24 can be regulated.

The collection plate 8 is arranged below the layer thickness regulating member 7, and similarly to the layer thickness regulating member 7, it is supported by blocks 20, 21 on both sides.

The density detector 9 is arranged above the collection plate 8 and detects the toner density by coming into contact with the developer 4. For example, the density detector 9 is configured to detect the magnetic permeability of the developer 4 using a magnetic bridge method and calculate the toner density. It becomes.

6- Further, the upper lid 13 is provided with a convex portion 33 having a curvature with a slight gap along the developing sleeve 2/I above the non-image portion at both ends of the developing sleeve 24, so that the developer 4 can be Sleeve 24 sleeve i! This prevents it from getting in between the side plates 14 and 15 of fi1. Furthermore, flange portions 34 and 35 are provided at the portions of the blocks 20 and 21 on both sides facing the developing sleeve 24, and there is a gap between the developing sleeve 24 and the side plate 14, 15 (). The thickness is approximately 2 to 0.4 mm to prevent the developer 4 from entering. Note that a brush 36 that contacts the photoreceptor drum 2 is provided at the tip of the cover 17 (1). This prevents the developer 4 from scattering above the container 1 from between the second cover 17 and the second cover 17.

Next, to explain the stirrer 5, 37 in Fig. 6 is the first spiral, which has an inner diameter of 8 mm and an outer diameter of 25 mm.
Two Ishinomaki spirals with a lead length of 20 to 40 mm are wound around the shaft 29 (front and rear).

Further, a second spiral 38 is coaxially provided on the outer periphery of the cylindrical sleeve 26 and has an outer diameter 32 to
It is wound with a left-handed double spiral with a length of 34 mm and a lead of 250 to 350 mm, and is fixed to the first spiral 37 so that it can rotate integrally therewith. Furthermore, the cylindrical sleeve 26 is provided with several first developer discharge holes 39 at the center of the opening of the first spiral 38 at a position 12 to 13 mm rotationally rearward of the second spiral 38, and a plurality of first developer discharge holes 39 are formed on the rear side. A second developer discharge hole 40 is opened from the root of the second spiral 38 to 90 degrees backward in rotation.

Two disks 41,42 are provided, bearings at both ends are adapted to prevent developer material 4 from entering portions 43,44. Further, the cylindrical sleeve 26 and the second spiral 38 are not provided in the length corresponding to the lead of the first spiral 37 from the second disk 42 on the front side to the rear side, and the first spiral 37 is It's exposed. A toner replenishment port 45 is located on the side of the exposed portion of the first spiral 37, and a toner receptacle with a curvature with a slight gap is provided below along the outer diameter of the first spiral 39. Department/16 is arranged.

When the agitator 5 rotates in the direction shown in the figure and the toner is supplied from the toner replenishing port 4 to the toner replenishing port 4, the developer 4 at the bottom of the toner replenishing port 45 is mixed and It is conveyed to the rear side by the spiral 37 (31, -) and enters the cylindrical sleeve 26. The developer 4 that has entered the cylindrical sleeve 26 continues to be stirred as shown in A and is moved to the rear side. On the way, the developer 4 that has been stirred to some extent is gradually drawn out of the cylindrical sleeve 26 from the first developer II' iJl hole 3 hole 9, and the second developer 1 on the rear side
By the time the toner reaches the outlet hole 40, the developer 4 replenished with toner is present over the entire axial direction of the circumference 11 of the cylindrical sleeve 26 of the agitator 5. Furthermore, the developer 4 that has come out of the cylindrical sleeve 2G is transferred to the second spiral 38.
: While being scraped up into the developing sleeve 24, it moves from the rear side to the front side. Finally, at 9- the toner supply port 45 is reached again and the above cycle is repeated. In other words, the flow of the developer 4 is such that the developer 4 whose concentration has become higher due to replenishment of 1-toner is sufficiently stirred and then used for development, and the developer 4 whose concentration has become lower is replenished with toner. is clear, and stable image density can always be obtained.

Next, to explain the magnet roller 6, as shown in FIGS. 4 and 7, the magnet 25 has three transport poles 83. N3, S4, and photosensitive drum 2
1 for holding the magnetic brush and performing development.
three main poles N1, and three collection tanks 81 for collecting the magnetic brushes after development. It is constructed with seven poles of N2.82.

The magnetic poles are arranged to have different polarities from the first transport pole S3 to the third recovery tank S2, and only the first transport pole S3 and the third transport pole S2 have the same polarity, The position of the weak magnetic force created between the two is near the line connecting the center of the magnet roller 6 and the center of the stirrer 5. As a result, the developer 4 that is attracted to the surface of the developing sleeve 24 and is reliably transported from the first transport pole S3 to the third collection +432 is reduced in the binding force due to the magnetic force after the third collection section 82. Due to the centrifugal force caused by the rotation of the developing sleeve and the action of gravity, the five-C is pulled away from the surface of the developing sleeve 24,
It will be blown towards the IN ff unit 5. This developer 4 is further sent to the agitator 'lA5 by the flow of the developer 4 generated by the rotation of the second spiral 38 of the agitator 5, and is again mixed with toner (developer 1, etc.) II. In other words, the developer 4, which has been exposed to the 1-ner process, is refreshed and used for development after being used for development. Since the lower angle 47 between the stirrer 5 and the agitator 5 has an inclination of II compared to the angle of repose of the developer 4, Jt'i!
Agent 4 is also less likely to sink to the bottom.

Further, the first transport pole 83 has a wide magnetic material disposed near the inside of the developing sleeve 24, and
The area near the peak value of the magnetic flux density on the surface covers the height from the top of the stirrer 5 to the tip of the collection plate 8. Therefore, the developer 4 is transferred from the top of the stirrer 5 to the collection plate 8.
It is attracted over the entire upper area of the developing sleeve 24 up to the tip,
A sufficient amount of developer is maintained according to the structure of the magnetic brush, and there is no shortage of developer supply. In addition, the height of the region i72 near the magnetic flux density peak value of the first transport pole S3 is up to the height of the tip of the collection plate 8, and the magnetic flux density is drastically reduced at a height higher than that, so the layer The excess developer 4 on the pressure regulating member 7 is less restrained by the magnetic force, and becomes easier to flow on the collection plate 8.

Further, the collection plate 8 is arranged so that its tip is located at the repose angle of the developer 4 from a position where the distance from the developing sleeve 24 is approximately the same as the distance from the lower surface of the layer thickness regulating member 7 that constitutes the passage for the developer 4. It is installed on a slight slope. Therefore, the excess developer 4 caused by the layer thickness regulating member 7 passes through a path with a constant gap, is less likely to stagnate or get compressed under the layer thickness regulating member 7, flows smoothly, and has an angle of repose. A slightly gentler inclination allows the flow to be controlled to a certain degree and flow more uniformly. Further, the layer thickness regulating member 7 is installed so that its wedge-shaped tip has a rake angle of about 45 degrees and a relief angle of about 15 degrees with respect to the developing sleeve 24, and the developer adsorbed on the developing sleeve 24 is The thickness of the layer is regulated by I, as if removing 4. Therefore, the stress applied to the developer 4 is reduced, the rotational torque is reduced (II), and the life of the developer 4 is extended.

Further, a collection part 48 with a gentler slope is installed on the collection plate 8, and the upper part thereof is approximately 3
The concentration detector D h+ is installed as a magnetic bridge type concentration detector having a flat probe surface 49 tilted at 0 degrees and with a gap of 3 to 4 mm at the closest point. And this collection section 7
The developer 4 flows between the roller 1 and the roller 49. Furthermore, a rectifying magnet 50 is installed at the top of the tip of the collecting section 48, with a vA pole SO having the same polarity as the first transport pole S3 facing downward 1'J, and rectifying the vA pole SO with the same polarity as the first transport pole S3. The magnetic (J) line generated by the magnetic pole SO is collected in the recovery section 48.
13- It should be approximately parallel to the top surface. As a result, the developer 4 between the collecting section 48 and the probe surface 49 has a stable, steady flow with little stagnation or surface collapse, and the output for concentration detection is stabilized. Note that if the distance between the collecting section 48 and the probe surface 49 is too narrow, the flow will begin to stagnate and the toner will not respond as sensitively even when replenishing the toner.
On the other hand, if it is widened too much, the detection output will fluctuate greatly due to fluctuations in the bed pressure of the flow, making it impossible to obtain a stable output no.

Further, the length of the first transport pole S3 is the same as the maximum width of the sheet on which the image is to be copied, and the other magnetic poles are longer than this. Therefore, the layer thickness regulating member 7 handles the swelling of the developer 4 due to an increase in magnetic flux near both ends of the magnetic pole, and the magnetic force acts to prevent it from spreading to both sides, making the layer thickness of the developer 4 uniform near both ends. Therefore, development can be performed without the developer falling off or the image becoming dark due to excessive contact between the photosensitive drums 2 at both end portions. In addition, all of the poles except the first transport pole S3 are longer than the image width, and therefore the area where the layer thickness of the developer 4 is reduced due to the decrease in force at both ends of the magnetic pole is outside the south width of the image. Since the developer 4 is used effectively at both ends of the magnetic pole, developer 4 is effectively used at both ends of the magnetic pole, and no excess developer 1 or developer 4 is generated, so the IIQ image is formed near both ends of the magnetic pole. The above block 20.2
The developer 4 that passes over the flange 711134.35 of the container 1 and enters the gap between both ends of the developing sleeve 24 and the side plates 14.15 of the container 1 is rapidly lost. Furthermore, on the inside of both 4J sides of the developing sleeve 24, there is a groove (slightly smaller than the outer diameter of the developing sleeve 24) approximately 15 mm outward from both ends of the magnetic pole.
Magnetic disks 51 and 52 having Y are arranged to reduce the magnetic flux density leaking outward from both ends of the developing sleeve 24. For this reason, 11i! FtA sleeve 24
IIN between both ends of the container 1 and the side plate 1'1.15 of the container 1.
(The &+ agent 4 is no longer drawn in, and even if there is developer 4 that enters, it is rare for the developing sleeve 2/1 to rotate while adhering it to both sides of the developing sleeve 24, and the developer 4 is drawn in from both ends of the developing sleeve 24.) will not scatter.

〔Effect of the invention〕

As explained above, according to the present invention, in a developing device that supplies a developer while moving to an area to be developed and develops the area to be developed, there is provided a container for storing the developer, and a developer in the container. a supply member for supplying the to-be-developed portion; and openings on the upstream and downstream sides of the supply member in the relative movement direction;
Since it is provided with a suction port for sucking the scattered developer, it has a soaking effect such that the scattered developer can be reliably sucked.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view showing a conventional example, Figs. 2 to 7 show an embodiment of the present invention, Fig. 2 is a perspective view, Fig. 3 is a cross-sectional plan view, and Fig. 4 is an exploded perspective view. A vertical side view, FIG. 5 is a perspective view showing the rear block,
FIG. 6 is a front view of the stirrer, and FIG. 7 is a partially sectional side view showing the magnet roller portion. 1... Container, 2... Developed area (photosensitive drum), 4
. . . Developer, 6. Supply member (magnet/roller), 12. 18. Suction port. 17- Figure 2+-1 Figure 3 2 Figure 4 Figure 5

Claims (1)

[Claims] A container for storing the developer, a supply member for supplying the developer in the container to the 11 parts to be developed, in an apparatus that supplies a developer while moving relative to the part to be developed to develop the part to be developed; A developing device characterized by comprising suction ports opening on an upstream side and a downstream side in the relative movement direction of the supply member and sucking the scattered developer.