US3882823A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stirring and scraping device for developing material
Assignee: Minolta Co Ltd
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Filing: 1974-07-09
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Granted: 1975-05-13
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Expires: 1994-07-09
Abstract
Abstract A stirring and scraping device for developing material for use in an electrophotographic copying apparatus which comprises a rotary member rotatably provided below a toner dispenser and adjacent to a rotary developing roller in which stationary magnets are enclosed. The rotary member further includes a rotary shaft provided with many equally spaced grooves cut around the shaft so as to form a roller portion having many square edges. Upon rotation of the member in engagement with the developing roller the developing material on the developing roller is attracted by the member magnetized by the stationary magnets and subsequently detached from the member by centrifugal force and its own weight while being sufficiently stirred and mixed with fresh toner powder from the toner dispenser.
Inventors
- 👤 Susumu Tanaka
- 👤 Yuji Enoguchi
- 👤 Hidetoshi Kawabata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 23:21
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/09
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
315 words
In a developing device for use in an electrophotographic copying apparatus which comprises a developing roller rotatably provided adjacent to a photoreceptor having a photoreceptor surface on the outer periphery thereof, said developing roller including a rotatable outer cylinder, and a plurality of stationary magnets enclosed in said outer cylinder and disposed in such positions that magnetic fields of said magnets intersect to attract and feed developing material onto said outer cylinder so as to form magnetic brush bristles on said outer cylinder for developing an electrostatic latent image formed on said photoreceptor surface into a visible toner powder image, a toner dispenser provided above said outer cylinder for replenishing said developing material with fresh toner powder, and a sump for said developing material provided below said developing roller, an improvement thereof for efficient stirring and mixing of said developer material with said fresh toner powder and scraping of said developer material off said outer cylinder after said developing comprises a stirring and scraping device composed of a rotary member provided below a toner dispenser and adjacent to an outer periphery of said outer cylinder, said rotary member which is provided with a plurality of grooves and square edges on an outer periphery thereof being adapted, during rotation thereof, to contact said developing material on said outer cylinder and to be magnetized by the magnetic force of said stationary magnets, said developing material being attracted onto said rotary member by magnetic force of the latter concentrating on said square edges and by a difference of strength of magnetic force between said square edges and said grooves, and subsequently dislodged from said rotary member by centrifugal force and decreasing magnetic force due to rotation of said rotary member and by the own weight of said developing material, durIng which process said developing material is stirred and mixed with said fresh toner powder from said toner dispenser.
Claim 2
Dependent Claim
315 words
In a developing device for use in an electrophotographic copying apparatus which comprises a developing roller rotatably provided adjacent to a photoreceptor having a photoreceptor surface on the outer periphery thereof, said developing roller including a rotatable outer cylinder, and a plurality of stationary magnets enclosed in said outer cylinder and disposed in such positions that magnetic fields of said magnets intersect to attract and feed developing material onto said outer cylinder so as to form magnetic brush bristles on said outer cylinder for developing an electrostatic latent image formed on said photoreceptor surface into a visible toner powder image, a toner dispenser provided above said outer cylinder for replenishing said developing material with fresh toner powder, and a sump for said developing material provided below said developing roller, an improvement thereof for efficient stirring and mixing of said developer material with said fresh toner powder and scraping of said developer material off said outer cylinder after said developing comprises a stirring and scraping device composed of a rotary member provided below a toner dispenser and adjacent to an outer periphery of said outer cylinder, said rotary member which is provided with a plurality of grooves and square edges on an outer periphery thereof being adapted, during rotation thereof, to contact said developing material on said outer cylinder and to be magnetized by the magnetic force of said stationary magnets, said developing material being attracted onto said rotary member by magnetic force of the latter concentrating on said square edges and by a difference of strength of magnetic force between said square edges and said grooves, and subsequently dislodged from said rotary member by centrifugal force and decreasing magnetic force due to rotation of said rotary member and by the own weight of said developing material, durIng which process said developing material is stirred and mixed with said fresh toner powder from said toner dispenser.
Claim 3
Dependent Claim
77 words
A stirring and scraping device for developer material as claimed in claim 1, wherein said rotary member comprises a shaft with a pair of friction rollers secured at opposite ends thereof for engagement and synchronous rotation with said outer cylinder, said shaft being provided with a plurality of equally spaced grooves cut around said shaft between said friction rollers to form a roller portion having square edges corresponding to the number of said grooves around said shaft.
Claim 4
Dependent Claim
68 words
A stirring and scraping device for developing material as claimed in claim 1, wherein said rotary member comprises a shaft provided with a plurality of equally spaced grooves cut around said shaft to form a roller portion having square edges corresponding to the number of said grooves around said shaft, said roller portion being adapted to engage an outer periphery of said outer cylinder for synchronous rotation therewith.
Claim 5
Dependent Claim
97 words
A stirring and scraping device for developing material as claimed in claim 1, wherein said rotary member comprises a shaft with a pair of friction rollers secured at opposite ends thereof for engagement and synchronous rotation with said outer cylinder, said shaft being provided, between said friction rollers, with a plurality of spiral projections in the form of screw which are disposed in such directions as to collect the attracted developing material at a middle portion of said shaft, so as to form a roller portion having square edges with corresponding number of grooves around said shaft.
Claim 6
Dependent Claim
88 words
A stirring and scraping device for developing material as claimed in claim 1, wherein said rotary member comprises a shaft provided with a plurality of spiral projections in the form of screw which are disposed in such directions as to collect the attracted developing material at a middle portion of said shaft, so as to form a roller portion having square edges with corresponding number of grooves around said shaft, said roller portion being adapted to engage an outer periphery of said outer cylinder for synchronous rotation therewith.
Claim 7
Dependent Claim
27 words
A stirring and scraping device for developing material as claimed in claim 1, wherein said rotary member is adapted to be driven by an independent drive means.
Claim 8
Dependent Claim
100 words
A stirring and scraping device for developing material as claimed in claim 1, wherein said rotary member comprises a shaft with a pair of friction rollers secured at opposite ends thereof for engagement and synchronous rotation with said outer cylinder, said shaft being provided with a plurality of equally spaced rollers fixedly disposed on said shaft between said friction rollers, each plane of said rollers being disposed to extend at a certain angle relative to an axis of said shaft so as to form a roller portion having square edges corresponding to the number of said rollers around said shaft.
Claim 9
Dependent Claim
91 words
A stirring and scraping device for developing material as claimed in claim 1, wherein said rotary member comprises a shaft provided with a plurality of equally spaced rollers fixedly disposed on said shaft, each plane of said rollers being disposed to extend at a certain angle relative to an axis of said shaft so as to form a roller portion haivng square edges corresponding to the number of said rollers around said shaft, said roller portion being adapted to engage an outer periphery of said outer cylinder for synchronous rotation therewith.
Claim 10
Dependent Claim
27 words
A stirring and scraping device for developing material as claimed in claim 1, wherein said rotary member comprises an axially splined roller fixedly mounted on a shaft.
Claim 11
Dependent Claim
27 words
A stirring and scraping device for developing material as claimed in claim 1, wherein said rotary member comprises an axially splined roller integrally formed with a shaft.
Claim 12
Dependent Claim
117 words
A developing device for use in an electrophotographic copying apparatus which comprises a rotatable developing roller disposed adjacent a photoreceptor member for develoPing an electrostatic latent image formed thereon, a plurality of stationary magnets enclosed in said developing roller for attracting developing material and forming magnetic brush on the surface of said roller as it rotates, a magnetizable rotary member parallely provided adjacent said developing roller and positioned in the vicinity of one said magnets for said member to be magnetized, said rotary member being adapted to rotate with said developing roller for attracting the developing material on said roller surface whereby the attracted developing material is agitated and mixed by the rotational movement of said member.
Claim 13
Dependent Claim
117 words
A developing device for use in an electrophotographic copying apparatus which comprises a rotatable developing roller disposed adjacent a photoreceptor member for develoPing an electrostatic latent image formed thereon, a plurality of stationary magnets enclosed in said developing roller for attracting developing material and forming magnetic brush on the surface of said roller as it rotates, a magnetizable rotary member parallely provided adjacent said developing roller and positioned in the vicinity of one said magnets for said member to be magnetized, said rotary member being adapted to rotate with said developing roller for attracting the developing material on said roller surface whereby the attracted developing material is agitated and mixed by the rotational movement of said member.
Claim 14
Dependent Claim
44 words
A developing device as claimed in claim 11, wherein said magnetizable rotary member comprises a shaft provided with a plurality of grooves cut and square edges occurring alternatively for causing the difference in magnetic force therebetween for agitation and mixing of the developing material.
Claim 15
Dependent Claim
38 words
A developing device as claimed in claim 11 further comprises a toner replenishing means disposed above said rotary member and said developing roller for toner replenshed from said means to fall between said rotary member and said roller.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-12 | 1978-11-11 | 1979-05-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-12 | 1982-11-11 | 1983-05-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-12 | 1986-11-11 | 1987-05-13 | $7700.00 | Window Closed / Lapsed |