Claims
- 1. An image transfer device in which a transfer belt is rotated and applied with a charge from a first electrode in contact with said transfer belt to transfer a toner image from an image carrier to a transfer medium carried on said transfer belt, said device comprising:
- a second electrode contacting said transfer belt; and
- a resistance element connected between said second electrode and ground, wherein said resistance element comprises a variable resistance element, said device further comprising control means for producing a ratio of a voltage applied from the first electrode to said transfer belt to an output current from said first electrode to said transfer belt and for controlling a resistance of said variable resistance element such that said ratio has a predetermined value.
- 2. An image transfer device in which a transfer belt is rotated and applied with a charge from a first electrode in contact with said transfer belt to transfer a toner image from an image carrier to said transfer belt, said device comprising:
- a second electrode contacting said transfer belt; and
- a resistance element connected between said second electrode and ground, wherein said resistance element comprises a variable resistance element, said device further comprises control means for producing a ratio of a voltage applied from the first electrode to said transfer belt to an output current from said first electrode to said transfer belt and for controlling a resistance of said variable resistance element such that said ratio has a predetermined value.
- 3. An image transfer device in which a transfer belt is rotated and applied with a charge from a first electrode in contact with said transfer belt to transfer a toner image from an image carrier to a transfer medium carried on said transfer belt, said device comprising:
- a second electrode contacting said transfer belt; and
- a resistance element connected between said second electrode and ground, wherein said resistance element comprises a variable resistance element, said device further comprising control means for producing a ratio of an output current from the first electrode to said transfer belt and a current from said transfer belt to said second electrode and for controlling a resistance of said variable resistance element such that said ratio has a predetermined value.
- 4. An image transfer device in which a transfer belt is rotated and applied with a charge from a first electrode in contact with said transfer belt to transfer a toner image from an image carrier to said transfer belt, said device comprising:
- a second electrode contacting said transfer belt; and
- a resistance element connected between said second electrode and ground, wherein said resistance element comprises a variable resistance element, said device further comprising control means for producing a ratio of an output current from the first electrode to said transfer belt and a current from said transfer belt to said second electrode, and for controlling a resistance of said variable resistance element such that said ratio has a predetermined value.
- 5. A method for forming images, comprising:
- rotating an image transfer belt;
- maintaining a first electrode in contact with said image transfer belt;
- applying a charge to said image transfer belt from a power source via said first electrode;
- feeding back a current from said image transfer belt to said power source via a second electrode which also contacts said image transfer belt;
- controlling a ratio of a voltage applied from the first electrode to said transfer belt to an output current from the first electrode to said transfer belt; and
- controlling the resistance of a variable resistance element such that said ratio has a predetermined value.
- 6. The method according to claim 5, further comprising:
- setting a variable resistance between said second electrode and said power source; and
- controlling the ratio of a voltage applied from the first electrode to the transfer belt to an output current from said first electrode to said transfer belt such that said ratio has a predetermined value.
- 7. The method according to claim 5, further comprising:
- setting a variable resistance between said second electrode and said power source; and
- controlling the ratio of an output current from the first electrode to said transfer belt and a current from said transfer belt to said second electrode such that said ratio has a predetermined value.
- 8. An image transfer device in which a transfer belt is rotated and applied with a charge from a first electrode in contact with said transfer belt to transfer a toner image from an image carrier to a transfer medium carried on said transfer belt, said device comprising:
- a second electrode contacting said transfer belt; and
- a resistance element connected between said second electrode and ground,
- wherein a ratio of a resistance of said transfer belt to a resistance of said resistance element is one of 1:1-100 and 10:1-100 and 100:1-100.
- 9. A device as claimed in claim 8, wherein the resistance of said transfer belt is a rear surface resistance of said belt contacting said second electrode.
- 10. A device as claimed in claim 8, wherein said resistance element has an electric resistance ranging from 10.sup.6 .OMEGA. to 10.sup.8 .OMEGA..
- 11. A device as claimed in claim 10, wherein said resistance element comprises a fixed resistance element.
- 12. A device as claimed in claim 8, wherein said resistance element has an electric resistance higher than a minimum electric resistance belonging to a predetermined electric resistance range particular to said belt.
- 13. A device as claimed in claim 12, wherein said resistance element comprises a fixed resistance element.
Priority Claims (2)
Number |
Date |
Country |
Kind |
4-099928 |
Apr 1992 |
JPX |
|
4-140590 |
Jun 1992 |
JPX |
|
Parent Case Info
This application is a continuation of application Ser. No. 08/046,795, filed on Apr. 16, 1993, now abandoned.
US Referenced Citations (10)
Foreign Referenced Citations (6)
Number |
Date |
Country |
4040962 |
Jun 1991 |
DEX |
0024683 |
Jan 1990 |
JPX |
0182787 |
Aug 1991 |
JPX |
0186876 |
Aug 1991 |
JPX |
0231274 |
Oct 1991 |
JPX |
2065558 |
Jul 1981 |
GBX |
Continuations (1)
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Number |
Date |
Country |
Parent |
46795 |
Apr 1993 |
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