Patent US5223900A successfully refreshed from Google Patents.
US5223900A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transfer roller with a resistance determined in accordance with its peripheral speed
Assignee: Canon Inc
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Filing: 1991-12-03
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Granted: 1993-06-29
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Expires: 2011-12-03
Abstract
Abstract An image forming apparatus includes a movable image bearing member; a transfer device cooperative with the image bearing member to form a nip, through which a transfer material is passed to electrostatically transfer an image from the image bearing member onto the transfer material; where the resistance R range providing proper image transfer is determined in accordance with the equation: -9.16×10.sup.3 ×v+11.68-0.65≦log.sub.10 (R×L) ≦-9.16×10.sup.3 ×v+11.68+0.65 where V (mm/sec) is movement speed of the image bearing member (v≧40), R (ohm) is a resistance of the transfer device when a voltage of 3 KV is applied between the image bearing member and the transfer device, and L (mm) is a length of the nip measured in a direction of a generating line of the image bearing member.
Inventors
- 👤 Takayasu Yuminamochi
- 👤 Koichi Tanigawa
- 👤 Akihiko Takeuchi
- 👤 Koichi Hiroshima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 07:33
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/14; G03G15/16; G03G15/1665; G03G15/167; G03G15/1685
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
124 words
An image forming apparatus, comprising: a movable image bearing member; transfer means cooperative with said image bearing member to form a nip, through which a transfer material is passed to electrostatically transfer an image from said image bearing member onto the transfer material; where the resistance R range providing proper image transfer is determined in accordance with the equation: -9.16×10.sup.-3 ×v+11.68-0.65≦log.sub.10 (R×L) ≦-9.16×10.sup.-3 ×v+11.68+0.65 where v (mm/sec) is movement speed of said image bearing member (v≧40), R (ohm) is a resistance of said transfer means when a voltage of 3 KV is applied between said image bearing member and said transfer means, and L (mm) is a length of the nip measured in a direction of a generating line of said image bearing member.
Claim 2
Dependent Claim
124 words
An image forming apparatus, comprising: a movable image bearing member; transfer means cooperative with said image bearing member to form a nip, through which a transfer material is passed to electrostatically transfer an image from said image bearing member onto the transfer material; where the resistance R range providing proper image transfer is determined in accordance with the equation: -9.16×10.sup.-3 ×v+11.68-0.65≦log.sub.10 (R×L) ≦-9.16×10.sup.-3 ×v+11.68+0.65 where v (mm/sec) is movement speed of said image bearing member (v≧40), R (ohm) is a resistance of said transfer means when a voltage of 3 KV is applied between said image bearing member and said transfer means, and L (mm) is a length of the nip measured in a direction of a generating line of said image bearing member.
Claim 3
Dependent Claim
31 words
An apparatus according to claim 1, further comprising a power source for supplying electric power between said image bearing member and said transfer means during transfer operation of said transfer means.
Claim 4
Dependent Claim
18 words
An apparatus according to claim 1, wherein said transfer means is in the form of a rotatable member.
Claim 5
Dependent Claim
16 words
An apparatus according to claim 1 or 3, wherein said transfer means has an elastic layer.
Claim 6
Dependent Claim
33 words
An apparatus according to claim 1 or 3, wherein said transfer means includes a conductive elastic layer and a resistance layer having a volume resistivity larger than that of said conductive elastic layer.
Claim 7
Dependent Claim
34 words
An apparatus according to claim 1, further comprising latent image forming means for forming an electrostatic latent image on said image bearing member and developing means for developing the electrostatic latent image with toner.
Claim 8
Dependent Claim
26 words
An apparatus according to claim 1, wherein said latent image has a polarity which is opposite from that of a charging polarity of said transfer means.
Claim 9
Dependent Claim
24 words
An apparatus according to claim 7, wherein a charging polarity of the latent image is the same as a charging polarity of the toner.
Claim 10
Dependent Claim
22 words
An apparatus according to claim 7 or 8, wherein said image bearing member is a photosensitive member having an organic photoconductive layer.
Claim 11
Dependent Claim
19 words
An apparatus according to claim 1 or 3, wherein said transfer means is press-contacted to said image bearing member.
Claim 12
Dependent Claim
18 words
An apparatus according to claim 1, wherein said image bearing member is in the form of a drum.
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) | 1996-06-28 | 1996-12-28 | 1997-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-06-28 | 2000-12-28 | 2001-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-06-28 | 2004-12-28 | 2005-06-29 | $7700.00 | Window Closed / Lapsed |