Patent US4581671A successfully refreshed from Google Patents.
Patent US4458627A successfully refreshed from Google Patents.
US4458627A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Developing apparatus for electrostatic image
Assignee: Canon Inc
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Filing: 1982-01-18
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Granted: 1984-07-10
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Expires: 2002-01-18
Abstract
Abstract A developing device for electrophotography includes a developer supporter faced to an image bearing member with a constant space maintained therebetween at a developing station, a developer supply and an elastic developer limiting member maintained in predetermined pressure contact with the developer supporter between the developer supply and the developing station to limit the thickness of developer supported on the supporter to a value not causing contact of the developer with the non-imaged area on the image bearing member.
Inventors
- 👤 Nagao Hosono
- 👤 Koichi Kinoshita
- 👤 Toru Takahashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:13
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/09; Y; Y10; Y10S; Y10S222/00; Y10S222/01
Claims Analysis
Total Claims: 36
Claim 1
Independent Claim
111 words
A developing apparatus for developing with a powder developer, comprising: a movable developer supporting member provided in facing relationship with an image carrying means in a developing station for developing a latent image carried on the image carrying means, said supporting member being separated from the image carrying means by a predetermined distance; means for supplying powder developer to said supporting member; and an elastic developer limiting member having a free end upstream of the developing station, with respect to the direction of movement of the developer, which is maintained in predetermined pressure contact with said developer supporting member at a position between said developer supply means and the developing station.
Claim 2
Dependent Claim
111 words
A developing apparatus for developing with a powder developer, comprising: a movable developer supporting member provided in facing relationship with an image carrying means in a developing station for developing a latent image carried on the image carrying means, said supporting member being separated from the image carrying means by a predetermined distance; means for supplying powder developer to said supporting member; and an elastic developer limiting member having a free end upstream of the developing station, with respect to the direction of movement of the developer, which is maintained in predetermined pressure contact with said developer supporting member at a position between said developer supply means and the developing station.
Claim 3
Dependent Claim
29 words
An apparatus according to claim 1, wherein said elastic limiting member has a hardness of 70 degrees and applies a pressure of between 0.4 and 40 grams per centimeter.
Claim 4
Dependent Claim
131 words
A developing apparatus for developing with a powder developer, comprising: a movable developer supporting member provided in a developing station in facing relationship with the surface of an image carrying member and separated therefrom by a predetermined distance; means for supplying powder developer to said movable developer supporting member; a first developer layer limiting member provided between said supply means and the developing station and separated from said developer supporting member by a predetermined distance; and a second developer layer limiting member provided between said first limiting member and the developing station, said second limiting member being composed of elastic material and having a free end system of the developing station, with respect to the direction of movement of the developer, maintained in predetermined pressure contact with said developer supporting member.
Claim 5
Dependent Claim
131 words
A developing apparatus for developing with a powder developer, comprising: a movable developer supporting member provided in a developing station in facing relationship with the surface of an image carrying member and separated therefrom by a predetermined distance; means for supplying powder developer to said movable developer supporting member; a first developer layer limiting member provided between said supply means and the developing station and separated from said developer supporting member by a predetermined distance; and a second developer layer limiting member provided between said first limiting member and the developing station, said second limiting member being composed of elastic material and having a free end system of the developing station, with respect to the direction of movement of the developer, maintained in predetermined pressure contact with said developer supporting member.
Claim 6
Dependent Claim
16 words
A developing apparatus according to claim 3, wherein said first limiting member is a rigid member.
Claim 7
Dependent Claim
111 words
A developing apparatus for developing with powder developer, comprising: a movable developer supporting member provided in a developing station in facing relationship with the surface of an image carrying member and separated therefrom by a predetermined distance; means for generating a magnetic field in the developing station; magnetic developer supply means for supplying magnetic powder developer to said developer supporting member; and an elastic developer layer limiting member provided at a position between said developer supply means and the developing station and having a free end upstream of the developing station, with respect to the direction of movement of the developer, maintained in predetermined pressure contact with said developer supporting member.
Claim 8
Dependent Claim
111 words
A developing apparatus for developing with powder developer, comprising: a movable developer supporting member provided in a developing station in facing relationship with the surface of an image carrying member and separated therefrom by a predetermined distance; means for generating a magnetic field in the developing station; magnetic developer supply means for supplying magnetic powder developer to said developer supporting member; and an elastic developer layer limiting member provided at a position between said developer supply means and the developing station and having a free end upstream of the developing station, with respect to the direction of movement of the developer, maintained in predetermined pressure contact with said developer supporting member.
Claim 9
Dependent Claim
102 words
A developing apparatus for developing with a powder developer, comprising: a movable developer supporting member provided in a developing station in facing relationship with the surface of an image carrying member and separated therefrom by a predetermined distance; magnetic developer supply means for supplying magnetic powder developer to said developer supporting member; and an elastic developer limiting member provided at a position between said developer supply means and the developing station and having a free end upstream of the developing station, with respect to the direction of movement of the magnetic developer maintained in predetermined pressure contact with said developer supporting member.
Claim 10
Dependent Claim
102 words
A developing apparatus for developing with a powder developer, comprising: a movable developer supporting member provided in a developing station in facing relationship with the surface of an image carrying member and separated therefrom by a predetermined distance; magnetic developer supply means for supplying magnetic powder developer to said developer supporting member; and an elastic developer limiting member provided at a position between said developer supply means and the developing station and having a free end upstream of the developing station, with respect to the direction of movement of the magnetic developer maintained in predetermined pressure contact with said developer supporting member.
Claim 11
Dependent Claim
130 words
A developing apparatus for developing with a powder developer, comprising: a movable developer supporting member provided in a developing station in facing relationship with the surface of an image carrying member and separated therefrom by a predetermined distance; means for generating a magnetic field in the developing station; magnetic developer supply means for supplying magnetic powder developer to said developer supporting member; an elastic developer limiting member at a position between said developer supply means and the developing station and having a free end system of the developing station, with respect to the direction of movement of the magnetic developer, maintained in predetermined pressure contact with said developer supporting means; and means for generating a magnetic field where said elastic limiting member is in contact with said developer supporting member.
Claim 12
Dependent Claim
130 words
A developing apparatus for developing with a powder developer, comprising: a movable developer supporting member provided in a developing station in facing relationship with the surface of an image carrying member and separated therefrom by a predetermined distance; means for generating a magnetic field in the developing station; magnetic developer supply means for supplying magnetic powder developer to said developer supporting member; an elastic developer limiting member at a position between said developer supply means and the developing station and having a free end system of the developing station, with respect to the direction of movement of the magnetic developer, maintained in predetermined pressure contact with said developer supporting means; and means for generating a magnetic field where said elastic limiting member is in contact with said developer supporting member.
Claim 13
Dependent Claim
46 words
A developing apparatus according to claim 7, wherein said means for generating a magnetic field in the developing station and said means for generating a magnetic field where said elastic limiting member is in contact with said developer supporting member are composed of the same magnet.
Claim 14
Dependent Claim
16 words
A developing apparatus according to claim 7, wherein said elastic limiting member is a rubber plate.
Claim 15
Dependent Claim
32 words
A developing apparatus according to claim 9, wherein said rubber limiting plate is maintained in pressure contact in the forward direction with respect to the moving direction of said developer supporting member.
Claim 16
Dependent Claim
32 words
A developing apparatus according to claim 9, wherein said rubber limiting plate is maintained in pressure contact in the reverse direction with respect to the moving direction of said developer supporting member.
Claim 17
Dependent Claim
114 words
A dry developing apparatus for developing latent images, comprising: developer supporting means upon which dry developer may be moved to a developing zone at which said developer supporting means faces a latent image carrying member; means for supplying dry developer to said developer supporting means; and an elastic thickness limiting member having a free end upstream of the developing zone, with respect to the direction of movement of the developer, which bears on said developer supporting means between the position where developer is supplied onto said developer supporting means and the developing zone, so as to limit the thickness of the developer layer which moves on said developer support means toward the developing zone.
Claim 18
Dependent Claim
114 words
A dry developing apparatus for developing latent images, comprising: developer supporting means upon which dry developer may be moved to a developing zone at which said developer supporting means faces a latent image carrying member; means for supplying dry developer to said developer supporting means; and an elastic thickness limiting member having a free end upstream of the developing zone, with respect to the direction of movement of the developer, which bears on said developer supporting means between the position where developer is supplied onto said developer supporting means and the developing zone, so as to limit the thickness of the developer layer which moves on said developer support means toward the developing zone.
Claim 19
Dependent Claim
26 words
A developing apparatus according to claim 12, wherein said developer supporting means comprises a member arranged for movement to carry the developer to the developing zone.
Claim 20
Dependent Claim
70 words
A developing apparatus according to any one of claims 12 or 13, including a further thickness limiting member which is positioned upstream of said elastic thickness limiting member with respect to the direction of movement of the developer so as to limit the thickness of the developer layer moving toward the elastic thickness limiting member and which is separated from the surface of said developer supporting means carrying the developer.
Claim 21
Dependent Claim
17 words
A developing apparatus according to claim 14, wherein said first thickness limiting member is a rigid member.
Claim 22
Dependent Claim
30 words
A developing apparatus according to claim 14, including a magnet member for producing magnetic fields in the developing zone and in the regions of each of said thickness limiting members.
Claim 23
Dependent Claim
31 words
A developing apparatus according to claim 13, wherein said developer supporting means comprises a cylindrical sleeve, said supplying means being arranged to supply developer onto the peripheral surface of said sleeve.
Claim 24
Dependent Claim
22 words
A developing apparatus according to claim 17, wherein said sleeve is rotatable about its longitudinal axis to cause movement of the developer.
Claim 25
Dependent Claim
24 words
A developing apparatus according to claim 13, wherein said developer supporting means comprises an endless belt arranged to rotate about a plurality of rollers.
Claim 26
Dependent Claim
18 words
A developing apparatus according to claim 12, including means for producing a magnetic field at the developing zone.
Claim 27
Dependent Claim
30 words
A developing apparatus according to claim 12, including means for producing a magnetic field in the region of contact between said elastic thickness limiting member and said developer supporting means.
Claim 28
Dependent Claim
38 words
A developing apparatus according to claim 12, including a magnet member which produces a magnetic field at both the developing zone and in the region of contact between said elastic thickness limiting member and the developer support means.
Claim 29
Dependent Claim
22 words
A developing apparatus according to claim 22, wherein said magnet member is stationary so that said magnetic fields produced thereby are stationary.
Claim 30
Dependent Claim
20 words
A developing apparatus according to claim 22, wherein said magnet member is movable to cause movement of said magnetic fields.
Claim 31
Dependent Claim
21 words
A developing apparatus according to claim 12, wherein said elastic thickness limiting member is in the form of a resilient plate.
Claim 32
Dependent Claim
38 words
A developing apparatus according to claim 25, wherein said resilient plate is arranged with a gap between it and said developer supporting means tapering toward the region of pressure contact in the direction of movement of the developer.
Claim 33
Dependent Claim
42 words
A developing apparatus according to claim 25, wherein said resilient plate is arranged with a gap between it and said developer supporting means tapering toward the region of pressure contact in a direction opposite to the direction of movement of the developer.
Claim 34
Dependent Claim
16 words
A developing apparatus according to claim 12, wherein said elastic thickness limiting member is a roller.
Claim 35
Dependent Claim
59 words
A developing apparatus according to claim 12, wherein at the developing zone the gap between said developer supporting means and the latent image carrying member is such as to avoid contact between the developer supported on said developer supporting means and the portion of the latent image on the latent image carrying member which is not to be developed.
Claim 36
Dependent Claim
53 words
A developing apparatus according to claim 12, including means for vibrating said elastic thickness limiting member to cause said thickness limiting member to oscillate in a direction transverse to the direction of movement of the developer, thereby to avoid the coagulation of developer between said developer supporting means and said thickness limiting member.
References Cited (Backward Citations)
US4154520A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-07-10 | 1988-01-09 | 1988-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-07-10 | 1992-01-09 | 1992-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-07-10 | 1996-01-09 | 1996-07-10 | $7700.00 | Window Closed / Lapsed |