US3823689A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Developing device for electrostatic charge images
Assignee: US Philips Corp
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Filing: 1972-09-18
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Granted: 1974-07-16
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Expires: 1992-09-18
Abstract
Abstract A developing device for a carrier provided with electrostatic charge images, consisting of a trough-like chamber which accommodates a paddle wheel. A vertical partition limits a gaplike space in which developing powder is forced upwards by slow rotation of the paddle wheel until it comes into contact with the carrier.
Inventors
- 👤 G Dietz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:58
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/09; G03G15/082
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
213 words
A device for developing electrostatic charge images which are formed on a carrier, comprising: a rotably supported paddle wheel for mixing and passing developing powder over a charged image surface of said carrier; a trough-like chamber containing said paddle wheel, said trough-like chamber comprising a front wall with an upper edge portion, a rear wall, side portions, and a bottom portion joining said front and rear walls and said side portions; a quantity of developing powder in said bottom portion thereof; a partition disposed in said chamber in proximity to a peripheral edge of said paddle wheel, said partition defining a conduit in conjunction with said front wall and said side portions of said chamber to conduct said developing powder into contact with said carrier; and guide means supported at an upper end of said conduit for guiding said carrier along a path over said upper edge portion and over an open upper portion of said trough-like chamber, said guide means defining a bend in said path directing said carrier upward away from said bottom portion over the upper end of said conduit, whereby the carrier is brought into contact with said developing powder in the region of, and just beyond, said bend, and excess developing powder falls back into said trough-like chamber.
Claim 2
Independent Claim
213 words
A device for developing electrostatic charge images which are formed on a carrier, comprising: a rotably supported paddle wheel for mixing and passing developing powder over a charged image surface of said carrier; a trough-like chamber containing said paddle wheel, said trough-like chamber comprising a front wall with an upper edge portion, a rear wall, side portions, and a bottom portion joining said front and rear walls and said side portions; a quantity of developing powder in said bottom portion thereof; a partition disposed in said chamber in proximity to a peripheral edge of said paddle wheel, said partition defining a conduit in conjunction with said front wall and said side portions of said chamber to conduct said developing powder into contact with said carrier; and guide means supported at an upper end of said conduit for guiding said carrier along a path over said upper edge portion and over an open upper portion of said trough-like chamber, said guide means defining a bend in said path directing said carrier upward away from said bottom portion over the upper end of said conduit, whereby the carrier is brought into contact with said developing powder in the region of, and just beyond, said bend, and excess developing powder falls back into said trough-like chamber.
Claim 3
Dependent Claim
48 words
The developing device of claim 1, wherein said guide means comprises said curved upper edge portion of said chamber, and a rotably supported cylinder disposed above and in close proximity to said edge portion so as to form a guiding gap therebetween for said carrier to pass therethrough.
Claim 4
Dependent Claim
69 words
The developing device of claim 1 wherein said paddle wheel comprises a cylindrical cage having blade-like paddle members radially extending outwardly from a center of said cage, said paddle members having a maximum width of one sixth of an outer diameter of the paddle wheel, the central region of said cage defined by radially inwardly directed edges of said blades being open to free movement of said developing powder.
Claim 5
Dependent Claim
61 words
The developing device of claim 2, wherein said developing powder contains iron particles and said guide cylinder provides a magnetic field to attract the iron in said developing powder, and thus attract said developing powder into contact with said imaged charged carrier as it passes through said guiding gap formed by said guide cylinder and the upper edge of said chamber.
Claim 6
Dependent Claim
55 words
The developing device of claim 2 comprising, in addition: pivotal support means for said trough-like chamber, said pivotal support means being spaced from said edge portion; and adjusting means to pivot said trough-like chamber to vary the distance between said edge portion and said rotatably supported cylinder and thereby the width of said guiding gap.
References Cited (Backward Citations)
US3599604A
Cited
US3682137A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-07-15 | 1978-01-14 | 1978-07-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-15 | 1982-01-14 | 1982-07-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-15 | 1986-01-14 | 1986-07-16 | $7700.00 | Window Closed / Lapsed |