US4126100A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for causing a developer powder to make an irregular motion in a developing zone
Assignee: Kyocera Mita Industrial Co Ltd
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Filing: 1977-07-26
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Granted: 1978-11-21
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Expires: 1997-07-26
Abstract
Abstract An apparatus for developing an electrostatic latent image formed on the surface of an electrostatic latent image-bearing material by applying a powdery developer, wherein means are provided for bringing the surface of a developer-retaining member retaining a layer of the powdery developer thereon into rolling contact with the surface of the image-bearing material in such a relation that a reservoir zone of the developer is formed at least upstream of the zone of rolling contact between the two surfaces, and means are provided for physically disturbing the developer in the reservoir zone to cause the developer to make an irregular motion.
Inventors
- 👤 Hitoshi Nishihama
- 👤 Katsuhiko Gotoda
- 👤 Minoru Motomura
- 👤 Takanobu Nakajima
- 👤 Tatsuo Aizawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 03:12
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/09; G03G15/082
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
186 words
An apparatus for developing an electrostatic latent image formed on the surface of an image-bearing material by applying a powdery developer thereto, said apparatus comprising a developer-retaining member capable of retaining a layer of the powdery developer on its surface, the surface being movable at a predetermined speed, means for feeding the solid powdery developer to the surface of said developer-retaining member at a predetermined position so that the developer-retaining member can have a layer of the developer on its surface, means for bringing the surface of the developer-retaining member into rolling contact with the surface of the image-bearing material through the layer of the developer at a predetermined position downstream of said first-mentioned predetermined position in the moving direction of the surface of said developer-retaining member, said contacting means bringing the two surfaces into rolling contact with each other in such a relation that a reservoir zone of the developer is formed upstream of and adjacent to the rolling contact zone of the two surfaces, and means for physically disturbing the developer in said reservoir zone to cause the developer to make an irregular motion.
Claim 2
Independent Claim
186 words
An apparatus for developing an electrostatic latent image formed on the surface of an image-bearing material by applying a powdery developer thereto, said apparatus comprising a developer-retaining member capable of retaining a layer of the powdery developer on its surface, the surface being movable at a predetermined speed, means for feeding the solid powdery developer to the surface of said developer-retaining member at a predetermined position so that the developer-retaining member can have a layer of the developer on its surface, means for bringing the surface of the developer-retaining member into rolling contact with the surface of the image-bearing material through the layer of the developer at a predetermined position downstream of said first-mentioned predetermined position in the moving direction of the surface of said developer-retaining member, said contacting means bringing the two surfaces into rolling contact with each other in such a relation that a reservoir zone of the developer is formed upstream of and adjacent to the rolling contact zone of the two surfaces, and means for physically disturbing the developer in said reservoir zone to cause the developer to make an irregular motion.
Claim 3
Dependent Claim
17 words
The apparatus of claim 1 wherein said disturbing means is a means for disturbing the developer magnetically.
Claim 4
Dependent Claim
28 words
The apparatus of claim 1 wherein said disturbing means is made of at least one fine metal wire disposed within the reservoir zone for mechanically disturbing the developer.
Claim 5
Dependent Claim
63 words
The apparatus of claim 1 wherein the developer-retaining member and the image-bearing material are arranged in the following relation d.sub.o ≦ d wherein d o is the minimum thickness of the developer layer to be retained on the surface of the developer-retaining member, and d is the minimum distance between the surface of the developer-retaining member and the surface of the image-bearing material.
Claim 6
Dependent Claim
46 words
The apparatus of claim 1 wherein said developer-retaining member is a rotatable hollow cylinder, and a roll-like permanent magnet is disposed within said retaining member so as to retain the developer on the surface of the retaining member by the action of the roll-like permanent magnet.
Claim 7
Dependent Claim
36 words
The apparatus of claim 5 wherein said roll-like permanent magnet is provided rotatably independently of the developer-retaining member, and the developer in the reservoir zone is magnetically disturbed by the rotation of the roll-like permanent magnet.
Claim 8
Dependent Claim
23 words
The apparatus of claim 6 wherein said roll-like permanent magnet has a plurality of poles of opposite polarities arranged alternatively on its periphery.
Claim 9
Dependent Claim
42 words
The apparatus of claim 7 which further includes means for adjusting the amount of the developer to be retained on the surface of the developer-retaining member, said adjusting means being located immediately downstream of said developer-feeding means with its forward end being
Claim 10
Dependent Claim
69 words
The apparatus of claim 8 wherein said distance (a) is 0.1 to 1.0 mm, the minimum distance (d) between the surface of the developer-retaining member and the surface of the image-bearing material is 0.1 to 1.0 mm, and said apparatus further comprising means to rotate the roll-like permanent magnet at a speed of at least 150 rpm in a direction opposite to the rotating direction of the developer-retaining member.
Claim 11
Dependent Claim
24 words
The apparatus of claim 9 wherein the rotating means is capable of rotating the roll-like magnet at a speed of 300 to 400 rpm.
Claim 12
Dependent Claim
29 words
The apparatus of claim 1 wherein the developer is a one-component developer, and the surface of the developer-retaining member has a surface roughness of not more than 12 S.
Claim 13
Dependent Claim
50 words
The apparatus of claim 1 wherein the developer is a relatively conductive one-component developer having a resistivity of not more than about 10 13 ohms.cm, and the developer-retaining member has an insulating coating having a resistance of about 10 3 to 10 9 ohms per cm 2 on its surface
Claim 14
Dependent Claim
20 words
The apparatus of claim 12 wherein the developer has a resistivity of not more than 5 × 10 11 ohms.cm.
Claim 15
Dependent Claim
24 words
The apparatus of claim 12 wherein the surface coating has a resistance of about 10 4 to 10 7 ohms per cm 2 .
Claim 16
Dependent Claim
11 words
The apparatus of claim 12 wherein the developer-retaining member is grounded.
Claim 17
Dependent Claim
13 words
The apparatus of claim 12 wherein said coating is a metallic oxide coating.
Claim 18
Dependent Claim
60 words
The apparatus of claim 1 wherein said developer-retaining member is a rotatable hollow cylinder, said image-bearing material is sheet-like, and said means for rolling contact is capable of rotating said developer-retaining member at a predetermined speed and simultaneously moves the image-bearing material relative to the developer-retaining member at substantially the same speed as the surface speed of the developer-retaining member.
Claim 19
Dependent Claim
45 words
The apparatus of claim 17 wherein said rolling contact means includes means for guiding the electrostatic latent image-bearing material, said means being of such a construction that the reservoir zone disappears when the rear end of the image-bearing material has passed the rolling contact zone.
Claim 20
Dependent Claim
17 words
The apparatus of claim 18 wherein said guiding means has raised and depressed portions on its surface.
Claim 21
Dependent Claim
22 words
The apparatus of claim 19 wherein said guide means includes at least one rotatable guide roller disposed opposite to the developer-retaining member.
Claim 22
Dependent Claim
69 words
The apparatus of claim 1 wherein said developer-retaining member is a rotatable hollow cylinder, said image-bearing material is a photosensitive plate mounted on a rotary drum, and said rolling contact means is capable of rotating said hollow cylinder and rotary drum in opposite directions to each other at such a speed that the surface speed of the hollow cylinder becomes substantially the same as that of the photosensitive plate.
Claim 23
Dependent Claim
16 words
The apparatus of claim 21 which further includes means for causing the reservoir zone to disappear.
Claim 24
Dependent Claim
55 words
The apparatus of claim 21 wherein said photosensitive plate has a length shorter than the entire peripheral length of said rotary drum, and at least a portion of that part of the rotary drum at which the photosensitive plate is not present is retracted from the surface of the photosensitive plate by a predetermined distance.
Claim 25
Dependent Claim
41 words
The apparatus of claim 21 Wherein said photosensitive plate is endless and mounted over the entire periphery of the rotary drum, and which further includes means for shutting off the supply of the developer to the surface of the developer-retaining member.
Claim 26
Independent Claim
252 words
An apparatus for developing an electrostatic latent image formed on the surface of an image-bearing material by applying a powdery developer thereto, said apparatus comprising a hollow cylindrical developer-retaining member rotatable in a predetermined direction, said retaining member having on its surface a relatively insulating coating having a resistance of 10 3 to 10 9 ohms per cm 2 and being kept at a grounded potential; a magnet having a plurality of poles of opposite polarities arranged alternately on its periphery, said magnet being provided within said developer-retaining member and rotatable independently of said developer-retaining member; developer-feed means for feeding a relatively conductive one-component developer having a resistivity of not more than 10 13 to the surface of the developer-retaining member at a predetermined position, thereby to retain the developer magnetically on the surface of the developer-retaining member; and means for bringing the surface of the developer-retaining member into rolling contact with the surface of the image-bearing material through a layer of the developer at a predetermined position downstream of said first-mentioned predetermined position in the rotating direction of the developer-retaining member, said rolling contact means effecting the rolling contact in a predetermined relation so that a reservoir zone of the developer is formed upstream of and adjacent to the rolling contact zone of the two surfaces, and said magnet being rotatable in a direction opposite to the rotating direction of the developer-retaining member to disturb the developer in the reservoir zone physically to cause the developer to make an irregular motion.
Claim 27
Independent Claim
252 words
An apparatus for developing an electrostatic latent image formed on the surface of an image-bearing material by applying a powdery developer thereto, said apparatus comprising a hollow cylindrical developer-retaining member rotatable in a predetermined direction, said retaining member having on its surface a relatively insulating coating having a resistance of 10 3 to 10 9 ohms per cm 2 and being kept at a grounded potential; a magnet having a plurality of poles of opposite polarities arranged alternately on its periphery, said magnet being provided within said developer-retaining member and rotatable independently of said developer-retaining member; developer-feed means for feeding a relatively conductive one-component developer having a resistivity of not more than 10 13 to the surface of the developer-retaining member at a predetermined position, thereby to retain the developer magnetically on the surface of the developer-retaining member; and means for bringing the surface of the developer-retaining member into rolling contact with the surface of the image-bearing material through a layer of the developer at a predetermined position downstream of said first-mentioned predetermined position in the rotating direction of the developer-retaining member, said rolling contact means effecting the rolling contact in a predetermined relation so that a reservoir zone of the developer is formed upstream of and adjacent to the rolling contact zone of the two surfaces, and said magnet being rotatable in a direction opposite to the rotating direction of the developer-retaining member to disturb the developer in the reservoir zone physically to cause the developer to make an irregular motion.
Claim 28
Dependent Claim
27 words
The apparatus of claim 25 wherein the surface coating of the developer-retaining member has a resistance of 10 4 to 10 7 ohms per cm 2 .
Claim 29
Dependent Claim
20 words
The apparatus of claim 25 wherein the developer has a resistivity of not more than 5 × 10 11 ohms.cm.
Claim 30
Dependent Claim
35 words
The apparatus of claim 25 wherein said magnet is a roll-like permanent magnet having at least 6 poles and a magnetic flux density on the surface of the developer-retaining member of at least 500 gauss.
Claim 31
Dependent Claim
75 words
The apparatus of claim 28 further comprising means to rotate said roll-like permanent magnet at a speed of at least 150 rpm, and which further includes means for adjusting the amount of the developer to be retained on the surface of the developer-retaining member, said adjusting means having a forward end being close to the surface of the developer-retaining member by a distance of 0.1 to 1.0 mm immediately downstream of said developer feed means.
Claim 32
Dependent Claim
25 words
The apparatus of claim 29 wherein the rotating means is capable of rotating the roll-like permanent magnet at a speed of 300 to 400 rpm.
Claim 33
Dependent Claim
13 words
The apparatus of claim 25 wherein said coating is a metallic oxide coating.
References Cited (Backward Citations)
US3045644A
Cited
US3176652A
Cited
US3437074A
Cited
US3793985A
Cited
US3834350A
Cited
US3703395A
Cited
US3552355A
Cited
US3641977A
Cited
US3666518A
Cited
US3754963A
Cited
US3839992A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-11-20 | 1982-05-22 | 1982-11-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-11-20 | 1986-05-22 | 1986-11-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-11-20 | 1990-05-22 | 1990-11-21 | $7700.00 | Window Closed / Lapsed |