Patent US3874328A successfully refreshed from Google Patents.
US3874328A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Developing device for electrophotography
Assignee: Ricoh Co Ltd
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Filing: 1973-05-21
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Granted: 1975-04-01
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Expires: 1993-05-21
Abstract
Abstract A developing roller has axially spaced flanges and is partly immersed in developing liquid. A cord material bearing an electrostatic latent image is moved along a path tangent to the periphery of the flanges of the developing roller, with the latent image bearing surface facing the developing roller. The image bearing portion of the card material is narrower than the axial distance between the flanges of the developing roller, such that the image bearing portion of the card material is spaced from the facing circumference of the developing roller. The roller is rotated at a different peripheral speed than the speed of the card material, but streaking of the developed image does not occur because the image bearing portion of the card material is not contacted directly by the developing roller. The card material moving toward the developing roller is tilted such that either its leading end is higher than its trailing end or vice versa depending on the direction of rotation of the developing roller so as to prevent developing liquid from reaching the side of the card material which faces away from the developing roller. After developing, the image bearing side of the card material is pressed against a blotter roller whose outer circumference is greater than the length of the image bearing portion of the card material in order to prevent the occurrence of an offset phenomenon.
Inventors
- 👤 Kenji Isonaka
- 👤 Saburo Hokari
- 👤 Tatsuya Watanabe
- 👤 Masamichi Furukawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 15:24
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/14; G03G15/18; G03G15/22; G03G15/26; Y; Y10; Y10S; Y10S271/00; Y10S271/90
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
216 words
A developing device for developing an electrostatic latent image formed on one side of a card material having a leading end and a traling end and having a length comparable to its width, said device comprising a developing roller having two axially spaced flanges, the axial distance between the flanges being less than the width of the card material but more than the width of the electrostatic latent image thereon, the diameter of each flange being greater than the diameter of the developing roller by a selected amount, means for rotating the developing roller, means for applying developing liquid to the developing roller, and means for moving the card material along a path tangential to the circumference of the flanges of the developing roller, with the image bearing side of the card material facing the developing roller and with the latent image thereof disposed intermediate the flanges of the developing roller, saiD moving means automatically moving the card material from a starting position in which the card material is out of contact with the developing roller, through a developing position in which at least a portion of the card material is in contact with the developing roller, and to an end position in which the card material is again out of contact with the developing roller.
Claim 2
Dependent Claim
216 words
A developing device for developing an electrostatic latent image formed on one side of a card material having a leading end and a traling end and having a length comparable to its width, said device comprising a developing roller having two axially spaced flanges, the axial distance between the flanges being less than the width of the card material but more than the width of the electrostatic latent image thereon, the diameter of each flange being greater than the diameter of the developing roller by a selected amount, means for rotating the developing roller, means for applying developing liquid to the developing roller, and means for moving the card material along a path tangential to the circumference of the flanges of the developing roller, with the image bearing side of the card material facing the developing roller and with the latent image thereof disposed intermediate the flanges of the developing roller, saiD moving means automatically moving the card material from a starting position in which the card material is out of contact with the developing roller, through a developing position in which at least a portion of the card material is in contact with the developing roller, and to an end position in which the card material is again out of contact with the developing roller.
Claim 3
Dependent Claim
51 words
A developing device as in claim 1 wherein the developing roller is rotated in the direction of movement of the card material and wherein the means for moving the card material includes means for preventing the trailing end of the card material from contacting the developing roller or the flanges thereof.
Claim 4
Dependent Claim
54 words
A developing device as in claim 1 wherein the developing roller is rotated in a direction opposie the direction of movement of the card material and wherein the means for moving the card material includes means for preventing the leading end of the card material from contacting the developing roller or the flanges thereof.
Claim 5
Dependent Claim
111 words
A developing device as in claim 1 wherein said moving means includes a hold-down roller and a squeezing roller disposed downstream of the developing roller along the path of the card material and facing each other, said hold-down roller including two flanges axially spaced from each other and extending radially outwardly of the hold-down roller, the distance between the facing ends of the two flanges being greater than the width of the image bearing portion of the card material but less than the width of the card material, said squeezing roller being spaced from the flanges of said hold-down roller by a distance smaller than the thickness of the card material.
Claim 6
Dependent Claim
32 words
A developing device as in claim 4 wherein the axial dimension of the squeezing roller is greater than the distance between the facing ends of the two flanges of the hold-down roller.
Claim 7
Dependent Claim
32 words
A developing device as in claim 4 wherein the axial dimension of the squeezing roller is less than the distance between the facing ends of the two flanges of the hold-down roller.
Claim 8
Dependent Claim
93 words
A developing device as in claim 1 including a blotter roller and a hold-down roller disposed downstream of the developing roller along the path of the card material, said blotter roller having an outer circumference at least equal to the length of the image bearing portion of the card material, said blotter roller disposed on the image bearing side of the card material, said hold-down roller maintained in pressing engagement with the blotter roller to nip the card material therebetween as the card material moves along its path downstream of the developing roller.
References Cited (Backward Citations)
US1987387A
Cited
US3104603A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-31 | 1978-09-30 | 1979-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-31 | 1982-09-30 | 1983-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-31 | 1986-09-30 | 1987-04-01 | $7700.00 | Window Closed / Lapsed |