EP0575159A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Image-forming method and apparatus
Assignee: Fujitsu Ltd
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Filing: 1993-06-16
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Granted: —
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Expires: 2013-06-16
Abstract
Abstract Disclosed are a cleanerless image forming apparatus and method which facilitate the collection of residual toners after transfer. The apparatus comprises a rotary endless latent carrier 1, a means 2a for charging the carrier, an exposure means 3 for forming an electrostatic latent image on the carrier, a means 4 for developing the electrostatic latent image by supplying polymerization toners while simultaneously cleaning residual polymerization toners from the carrier; and a means 5a for transferring the polymerization toners from the rotary endless latent carrier 1 to a sheet P. This apparatus uses polymerization toners which are smoother and more uniform than pulverised toners. In a modification, the transfer means 5a is a rotary transfer roller 50 which is more effective than a corona discharge alone. In a further modification, the charging means 2a includes a rotary charging brush 20 which picks up residual toner and gives it the correct charge for removal from the drum 1 by the developer 4.
Inventors
- 👤 Sachio Fujitsu Limited Sasaki
- 👤 Jun Fujitsu Limited Kodama
- 👤 Tomohisa Fujitsu Limited Mikami
- 👤 Masatoshi Fujitsu Limited Kimura
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 08:34
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G21/00; G03G13/00; G03G13/14; G03G13/16; G03G15/02; G03G15/0208; G03G15/0216; G03G21/0005; G03G21/0064; G03G9/00; G03G9/08; G03G9/0802; G03G9/0804; G03G9/0806; G03G9/0827; G03G2215/00; G03G2215/06; G03G2215/0602; G03G2215/0604; G03G2215/0607; G03G2215/0609; G03G2221/00; G03G2221/0005
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
93 words
An image-forming apparatus comprising: a rotary endless carrier (1) on which a latent image can be formed; a means (2a) for charging the carrier; a means (3) for forming an electrostatic latent image on the carrier; a means (4) for developing the electrostatic latent image on the carrier; a means (4) for developing the electrostatic latent image on the carrier by supplying polymerization toners and for cleaning any residual polymerization toners remaining on the carrier; and a means (5a) for transferring the polymerization toners on the rotary endless latent carrier to a sheet.
Claim 2
Dependent Claim
20 words
An image-forming apparatus according to claim 1, wherein the said toners are one-component non-magnetic polymerization toners or magnetic polymerization toners.
Claim 3
Dependent Claim
140 words
An image-forming apparatus comprising: a rotary endless carrier (1) on which a latent image can be formed; a means (2a) for charging the carrier; a means (3) for forming an electrostatic latent image on the carrier; a means (4) for developing the electrostatic latent image on the carrier; a means (4) for developing the electrostatic latent image on the carrier by supplying toners and for cleaning any residual toners remaining on the carrier; and a means (5a) for transferring the toners on the rotary endless latent carrier to a sheet, in which the transfer means (5a) has a rotary transfer roller (50) for transferring the toners on the carrier (1) to a sheet (P) by sandwiching the sheet between the rotary carrier (1) and the rotary transfer roller (50), and a means (51) for electrifying the rotary transfer roller (50).
Claim 4
Dependent Claim
22 words
An image-forming apparatus according to claim 3, wherein the electrifying means (51) comprises a constant-current source for supplying a constant transfer current.
Claim 5
Dependent Claim
123 words
An image-forming apparatus comprising: a rotary endless carrier (1) on which a latent image can be formed; a means (2a) for charging the carrier; a means (3) for forming an electrostatic latent image on the carrier; a means (4) for developing the electrostatic latent image on the carrier; a means (4) for developing the electrostatic latent image on the carrier by supplying toners and for cleaning any residual toners remaining on the carrier; and a means (5a) for transferring the toners on the rotary endless latent carrier to a sheet, in which the charging means (2a) includes a rotary charging brush (20) for charging the rotary endless latent carrier and a means (23,24) for supplying a charging voltage to the rotary charging brush.
Claim 6
Dependent Claim
27 words
An image-forming apparatus according to claim 5, wherein the said brush-charging means has a constant voltage source (23) and an AC voltage source (24) connected in series.
Claim 7
Dependent Claim
63 words
An image-forming apparatus according to claim 5 or 6, wherein the charging means (2a) further includes a housing covering the rotary charging brush (20), on which housing are provided sputtering-preventing members (22) for covering the inlet and outlet portions of the housing, and a projection (25) which in use comes into contact with the rotary charging brush in order to dislodge toner particles.
Claim 8
Dependent Claim
24 words
An image-forming apparatus according to any of claims 5 to 7, wherein the charging means (2a) is provided above the endless latent carrier (1).
Claim 9
Dependent Claim
61 words
An image-forming apparatus according to any of claims 5 to 8, in which the transfer means (5a) has a rotary transfer roller (50) for transferring the toners on the carrier (1) to a sheet (P) by sandwiching the sheet between the rotary carrier (1) and the rotary transfer roller (50); and a means (51) for electrifying the rotary transfer roller (50).
Claim 10
Dependent Claim
18 words
An image-forming apparatus according to any of claims 3 to 9, in which the toners are polymerization toners.
Claim 11
Dependent Claim
74 words
An image-forming method comprising: a first step of charging a rotary endless latent carrier (1); a second step of forming an electrostatic latent image on the rotary endless latent carrier; a third step of developing the electrostatic latent image by supplying polymerization toners, while cleaning residual polymerization toners from the rotary endless latent carrier; and a fourth step of transferring the supplied polymerization toners on the rotary endless latent carrier to a sheet (P).
Claim 12
Dependent Claim
19 words
An image-forming method according to claim 11, wherein the toners are one-component non-magnetic polymerization toners or magnetic polymerization toners.
Claim 13
Dependent Claim
109 words
An image-forming method comprising: a first step of charging a rotary endless latent carrier (1); a second step of forming an electrostatic latent image on the rotary endless latent carrier; a third step of developing the electrostatic latent image by supplying toners, while cleaning residual toners from the rotary endless latent carrier; and a fourth step of transferring the supplied toners on the rotary endless latent carrier to a sheet (P), in which the fourth step, of transferring the toners from the rotary endless latent carrier to a sheet, is done by sandwiching the sheet between the rotary endless latent carrier (1) and an electrified rotary transfer roller (50).
Claim 14
Dependent Claim
20 words
An image-forming method according to claim 13, in which the electrified transfer roller is supplied with a constant transfer current.
Claim 15
Dependent Claim
97 words
An image-forming method comprising: a first step of charging a rotary endless latent carrier (1); a second step of forming an electrostatic latent image on the rotary endless latent carrier; a third step of developing the electrostatic latent image by supplying toners, while cleaning residual toners from the rotary endless latent carrier; and a fourth step of transferring the supplied toners on the rotary endless latent carrier to a sheet (P), in which the first step, of charging the rotary endless latent carrier (1), is performed by a rotary charging brush (20) supplied with a charging voltage.
Claim 16
Dependent Claim
34 words
An image-forming method according to claim 15, wherein the charging voltage applied in the first step to the rotary charging brush (2) is made up of a constant voltage and a superimposed AC voltage.
Claim 17
Dependent Claim
52 words
An image-forming method according to claim 15 or 16, in which, during the first step, toners are brushed off the rotary charging brush (20) on to the rotary endless latent carrier (1) by a projection provided on a housing (21) of the brush coming into contact with the brush as it rotates.
Claim 18
Dependent Claim
49 words
An image-forming method according to any of claims 15 to 17, in which the fourth step, of transferring the toners from the rotary endless latent carrier to a sheet, is done by sandwiching the sheet between the rotary endless latent carrier (1) and an electrified rotary transfer roller (50).
Claim 19
Dependent Claim
18 words
An image-forming method according to any of claims 13 to 18, in which the toners are polymerization toners.
References Cited (Backward Citations)
No citation records indexed.
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