Patent US4583490A successfully refreshed from Google Patents.
US4583490A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thin developer layer forming apparatus
Assignee: Canon Inc
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Filing: 1984-08-08
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Granted: 1986-04-22
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Expires: 2004-08-08
Abstract
Abstract A thin developer layer forming apparatus including a developer supply container, having an opening, for containing a developer and magnetic particles, an endlessly movable developer carrying member for carrying the developer, which is movable between an inside of the developer supply container and an outside of the developer supply container through the opening, a magnetic particle confining member, provided to an outer surface of the developer carrying member with a gap, and a magnet for generating a fixed magnetic field, having a magnetic pole disposed inside of the carrying member and upstream of the confining member with respect to movement of the developer carrying member, wherein the confining member is inclined toward downstream with respect to the movement of the developer carrying member to confine the magnetic particles within the developer supply container and to apply only the developer on the developer carrying member.
Inventors
- 👤 Fumitaka Kan
- 👤 Hatsuo Tajima
- 👤 Atsushi Hosoi
- 👤 Masanori Takenouchi
- 👤 Takashi Saito
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:48
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/09
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
151 words
A thin developer layer forming apparatus, comprising: a developer supply container, having an opening, for containing a developer and magnetic particles; an endlessly movable developer carrying member for carrying the developer and which is movable between the inside of said developer supply container and the outside of said developer supply container through the opening; a magnetic-particle confining member of magnetic material and spaced from an outer surface of said developer carrying member to define a gap therebetween; and means for generating a fixed magnetic field, having magnetic pole means disposed inside of said carrying member and upstream of said confining member with respect to the movement direction of said developer carrying member; wherein said confining member is inclined toward downstream with respect to the movement direction of said developer carrying member to confine the magnetic particles within said developer supply container and apply only the developer on said developer carrying member.
Claim 2
Dependent Claim
151 words
A thin developer layer forming apparatus, comprising: a developer supply container, having an opening, for containing a developer and magnetic particles; an endlessly movable developer carrying member for carrying the developer and which is movable between the inside of said developer supply container and the outside of said developer supply container through the opening; a magnetic-particle confining member of magnetic material and spaced from an outer surface of said developer carrying member to define a gap therebetween; and means for generating a fixed magnetic field, having magnetic pole means disposed inside of said carrying member and upstream of said confining member with respect to the movement direction of said developer carrying member; wherein said confining member is inclined toward downstream with respect to the movement direction of said developer carrying member to confine the magnetic particles within said developer supply container and apply only the developer on said developer carrying member.
Claim 3
Dependent Claim
59 words
An apparatus according to claim 1, wherein said confining member is inclined, at an angle of 45 degrees--90 degrees with respect to a line which is normal to the outer surface of said developer carrying member and which passes through a tip of said confining member, toward downstream with respect to the movement direction of said developer carrying member.
Claim 4
Dependent Claim
25 words
An apparatus according to claim 1, wherein said confining member extends substantially along a direction of a magnetic field formed by said magnetic pole means.
Claim 5
Dependent Claim
25 words
An apparatus according to claim 2, wherein said confining member extends substantially along a direction of a magnetic field formed by said magnetic pole means.
Claim 6
Dependent Claim
46 words
An apparatus according to claim 1, wherein said developer carrying member is a non-magnetic sleeve, and said magnetic pole means is disposed 20-120 degrees upstream, from a vertical line which passes through the center of said sleeve, with respect to the movement direction of said sleeve.
Claim 7
Dependent Claim
37 words
An apparatus according to claim 5, wherein said confining member is disposed in a range which satisfies, Hθ(θ)≧Hr(θ) where Hr(θ) is a normal component of the magnetic field, and Hθ(θ) is a tangential component of the same.
Claim 8
Dependent Claim
23 words
An apparatus according to claim 1, wherein said confining member is spaced from said developer carrying member by a clearance of 100-1000 microns.
Claim 9
Dependent Claim
17 words
An apparatus according to claim 7, wherein the magnetic particles have a particle size of 30-200 microns.
Claim 10
Dependent Claim
33 words
An apparatus according to claim 1, further comprising a magnetic member, disposed adjacent to a position of said developer container where said developer carrying member moves toward the inside of said developer container.
Claim 11
Dependent Claim
24 words
An apparatus according to claim 9, wherein said magnetic field generating means has one magnetic pole between said confining member and said magnetic member.
Claim 12
Dependent Claim
13 words
An apparatus according to claim 1, wherein said developer is a non-magnetic toner.
Claim 13
Dependent Claim
53 words
An apparatus according to claim 1, wherein said developer carrying member is opposed to an image bearing member bearing an electrostatic latent image thereon to form a developing station where the developer in the form of a thin layer is applied to the image bearing member to develop the electrostatic latent image thereon.
Claim 14
Dependent Claim
54 words
An apparatus according to claim 1, wherein said magnetic particle confining member includes a blade of magnetic material, and said carrying member includes a sleeve of non-magnetic material, and wherein said magnetic blade has an end forming said gap with said sleeve and extends codirectionally with a magnetic field formed at the end thereof.
Claim 15
Dependent Claim
212 words
A thin developer layer forming apparatus, comprising: a developer supply container, having an opening, for containing a non-magnetic developer and magnetic particles; an endlessly movable developer carrying sleeve for carrying the developer, which is movable between an inside of said developer supply container and an outside of said developer supply container through the opening; a confining member spaced apart from an outer surface of said developer carrying sleeve to form a gap therebetween at a position θ degrees away from a vertical line m passing through the center of said sleeve and upstream with respect to the rotation direction of said sleeve; means for generating a fixed magnetic field having magnetic pole means disposed inside of said carrying member; wherein a normal line n to the outer surface of said sleeve at a position where said gap is formed forms the angle θ with said vertical line m, wherein a magnetic force Rθ in a tangential direction on the sleeve at the gap is larger than a magnetic force Rr in the normal direction n thereat, and wherein the coefficient of friction f and said angle θ satisfy θ≧Tan -1 f so as to supply substantially only non-magnetic developer on said sleeve while the magnetic particles are confined by the confining member.
Claim 16
Dependent Claim
212 words
A thin developer layer forming apparatus, comprising: a developer supply container, having an opening, for containing a non-magnetic developer and magnetic particles; an endlessly movable developer carrying sleeve for carrying the developer, which is movable between an inside of said developer supply container and an outside of said developer supply container through the opening; a confining member spaced apart from an outer surface of said developer carrying sleeve to form a gap therebetween at a position θ degrees away from a vertical line m passing through the center of said sleeve and upstream with respect to the rotation direction of said sleeve; means for generating a fixed magnetic field having magnetic pole means disposed inside of said carrying member; wherein a normal line n to the outer surface of said sleeve at a position where said gap is formed forms the angle θ with said vertical line m, wherein a magnetic force Rθ in a tangential direction on the sleeve at the gap is larger than a magnetic force Rr in the normal direction n thereat, and wherein the coefficient of friction f and said angle θ satisfy θ≧Tan -1 f so as to supply substantially only non-magnetic developer on said sleeve while the magnetic particles are confined by the confining member.
Claim 17
Dependent Claim
55 words
An apparatus according to claim 14, wherein said confining member includes a magnetic member, and said confining member has an end adjacent to said magnetic pole means, and wherein said confining member extends from the end toward the downstream with respect to the rotation of said developer carrying sleeve away from said developer carrying sleeve.
Claim 18
Dependent Claim
53 words
An apparatus according to claim 14, wherein said developer carrying member is opposed to an image bearing member bearing an electrostatic latent image thereon to form a developing station where the developer in the form of a thin layer is applied to the image bearing member to develop the electrostatic latent image thereon.
Claim 19
Dependent Claim
152 words
A thin developer layer forming apparatus, comprising: a developer supply container, having an opening, for containing a developer and magnetic particles; an endlessly movable developer carrying member for carrying the developer, which is movable between an inside of said developer supply container and an outside of said developer supply container through the opening; a magnetic-particle confining member of magnetic material and spaced from an outer surface of said developer carrying member to define a gap therebetween; a magnetic member, disposed adjacent to a position of said developer container where said developer carrying member moves toward the inside of said developer container; means for generating a fixed magnetic field, having one magnetic pole between said confining member and said magnetic member, wherein said one magnetic pole cooperates with said confining member to confine the magnetic particles at said gap, and also cooperates with said magnetic member to confine magnetic particles at said position.
Claim 20
Dependent Claim
152 words
A thin developer layer forming apparatus, comprising: a developer supply container, having an opening, for containing a developer and magnetic particles; an endlessly movable developer carrying member for carrying the developer, which is movable between an inside of said developer supply container and an outside of said developer supply container through the opening; a magnetic-particle confining member of magnetic material and spaced from an outer surface of said developer carrying member to define a gap therebetween; a magnetic member, disposed adjacent to a position of said developer container where said developer carrying member moves toward the inside of said developer container; means for generating a fixed magnetic field, having one magnetic pole between said confining member and said magnetic member, wherein said one magnetic pole cooperates with said confining member to confine the magnetic particles at said gap, and also cooperates with said magnetic member to confine magnetic particles at said position.
Claim 21
Dependent Claim
53 words
An apparatus according to claim 17, wherein said developer carrying member is opposed to an image bearing member bearing an electrostatic latent image thereon to form a developing station where the developer in the form of a thin layer is applied to the image bearing member to develop the electrostatic latent image thereon.
Claim 22
Dependent Claim
48 words
An apparatus according to claim 17, wherein said confining member has an end adjacent to said one magnetic pole and wherein said confining member extends from the end toward the downstream with respect to the rotation direction of said developer carrying sleeve away from said developer carrying sleeve.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-04-21 | 1989-10-21 | 1990-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-04-21 | 1993-10-21 | 1994-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-04-21 | 1997-10-21 | 1998-04-22 | $7700.00 | Window Closed / Lapsed |