Claims
- 1. A recording apparatus comprising:
- a cylindrical image carrier having a toner image developed thereon,
- a transfer station having a transfer unit located above the imaged carrier to transfer the toner imaged to an underside surface of a recording medium having a leading end and moving along a predetermined path extending between the image carrier and the transfer unit,
- a fixing unit, provided along the path and downstream of a point at which the recording medium ejected from the transfer station is separated from the image carrier, for fixing the toner image onto the underside surface of the recording medium, said fixing unit including at least one pair of a heat roll and a backup roll which come into contact with each other to define a nip which forms an entrance through which the recording medium having the toner image transferred thereon by the transfer unit is introduced into the fixing unit, such that the leading end of the recording medium moves downwardly after separating from the imaged carrier due to gravity force to a point in line with the entrance of the fixing unit, so that the leading end of the recording medium is guided into the entrance of the fixing unit,
- means, provided only upstream of a point at which the toner image is transferred to the recording medium, for orienting upward the leading end of the recording medium only by the stiffness of the recording medium when the leading end of the recording medium is being fed toward the transfer station,
- wherein said entrance of said fixing unit is located below a point of separation of the recording medium from the image carrier, and is defined by an intersection point between a center line connecting the center points of the heat roll and the backup roll and the point of contact between the two rolls, and
- wherein said center line is inclined at an angle between about 10.degree. and 18.degree. with respect to vertical and away from the imaged carrier, and a line connecting said intersection point and said separation is declined at an angle between about 5.degree. and 10.degree. with respect to horizontal.
- 2. A recording apparatus according to claim 1, wherein said inclination angle is approximately 10.degree..
- 3. A recording apparatus according to claim 1, wherein a line connecting the intersection point and the separation point is inclined at approximately 7.degree. with respect to the horizontal.
- 4. A recording apparatus according to claim 1, further comprising an electrically conductive and grounded guide which extends along the path of the recording medium between the transfer unit and the fixing unit.
- 5. A recording apparatus according to claim 4, wherein said grounded guide is located above the path of the recording medium so as to come into contact with an upper surface of the recording medium.
- 6. A recording apparatus according to claim 5, wherein said guide is rigidly connected to the transfer unit.
- 7. A recording apparatus comprising:
- a cylindrical image carrier having a toner image developed thereon,
- a transfer station having a non-contact type transfer charger unit located above the imaged carrier to transfer the toner image onto an underside surface of a recording medium having a leading end and moving along a predetermined path extending between the imaged carrier and the transfer unit,
- a fixing unit for fixing the toner imaged on the recording medium discharged from the transfer station, and having a nip portion located at a position such that a line of travel of the recording medium droops towards the nip portion so as to guide the recording medium by gravity; and
- means, provided only upstream of a point where the toner image is transferred to the recording medium, for orienting upward the leading end of the recording medium only by stiffness of the recording medium when the leading end of the recording medium is being fed toward the transfer station,
- whereby said recording medium is led through the transfer station and to the fixing unit by gravity induced bending of the recording medium.
- 8. A recording apparatus according to claim 7, wherein said orienting means comprises guide rollers provided upstream of the transfer station and on opposite sides of the path of the recording medium and located at a level lower than the transfer unit.
- 9. A recording apparatus according to claim 8, wherein said guide rollers are feed rollers for feeding the recording medium to the image carrier and changing the direction of feed of the recording medium.
- 10. A recording apparatus according to claim 7, further comprising a fixing unit for fixing the toner imaged onto the recording medium, said fixing unit comprising a heat roll and a backup roll which comes into contact with the heat roll at a contact point located at a level lower than a separation point at which the recording medium is separated from the imaged carrier, the vertical position of said contact point being selected to be located on the extension of travel of the leading end of the recording medium and being dependent on the weight and stiffness of the recording medium.
- 11. A recording apparatus according to claim 10, further comprising a grounded guide plate for guiding the recording medium ejected from the transfer unit into the fixing unit.
- 12. A recording apparatus comprising:
- a cylindrical image carrier having a toner image developed thereon,
- a transfer station having a non-contact type transfer unit located above the imaged carrier to transfer the toner image to an underside surface of a recording medium having a leading end and moving along a predetermined path extending between the imaged carrier and the transfer unit, the non-contact type transfer unit comprises a housing made of metal which is connected to the ground,
- a fixing unit, provided along the path and downstream of a point at which the recording medium ejected from the transfer station is separated form the image carrier, for fixing the toner image onto the underside surface of the recording medium, said fixing unit including at least one pair of a heat roll and a backup roll which comes into contact with each other to define a nip which forms an entrance through with the recording medium having the toner image transferred thereon by the transfer unit is introduced in to the fixing unit the nip of the fixing unit being located below a point of the transfer station,
- means, provided only upstream of a point at which the toner image is transferred to the recording medium, for orienting upward the leading end of the recording medium only by the stiffness of the recording medium when the leading end of the recording medium is being fed toward the transfer station, and
- an electrical conductor plate which is located along a path extending from the transfer station to the nip, said plate being connected tot he housing of the non-contact type transfer unit and being electrically grounded through the housing thereof.
- 13. A recording apparatus according to claim 12, wherein said guiding means is a grounded guide located above the path of the recording medium so as to come into contact with an upper surface of the recording medium,
- 14. A recording apparatus according to claim 13, wherein said guide is rigidly connected to the transfer unit.
- 15. A recording apparatus according to claim 13, wherein said fixing unit comprises at least one pair of a heat roll and a backup roll, which come into contact with each other to define a nip which forms said entrance of said fixing unit.
- 16. A recording apparatus according to claim 15, wherein said entrance of the fixing unit is defined by an intersection point between a center line connecting the center points of the heat roll and the backup roll and the point of contact between the two rolls and wherein said center line in inclined at a predetermined angle of inclination with respect to the vertical.
- 17. A recording apparatus according to claim 16, wherein said inclination angle is approximately 10.degree..
Priority Claims (3)
Number |
Date |
Country |
Kind |
62-108998 |
May 1987 |
JPX |
|
62-116992 |
May 1987 |
JPX |
|
62-228364 |
Sep 1987 |
JPX |
|
Parent Case Info
This is a continuation of copending application Ser. No. 07/191,159 filed on May 6, 1988, now abandoned.
US Referenced Citations (9)
Foreign Referenced Citations (6)
Number |
Date |
Country |
0017034 |
Feb 1979 |
JPX |
0048859 |
Mar 1985 |
JPX |
0235177 |
Nov 1985 |
JPX |
61-141470 |
Jun 1986 |
JPX |
0175649 |
Aug 1986 |
JPX |
0194261 |
Aug 1987 |
JPX |
Continuations (1)
|
Number |
Date |
Country |
Parent |
191159 |
May 1988 |
|