1. An image forming apparatus which sequentially arranges a charging device, a developing device, a transfer device, and a charge eliminating device around a single-layer-type electrophotographic photoconductor, wherein
the charging device charges a surface of the single-layer-type electrophotographic photoconductor with a positive polarity,
a precharging device having a conductive member is arranged on an upstream side of the charge eliminating device,
the conductive member is brought into contact with the surface of the single-layer-type electrophotographic photoconductor, and
a current density Ib (\u03bcAm2) of an injected current into the single-layer-type electrophotographic photoconductor from the conductive member is set to a value of 700(\u03bcAm2) or more.
2. The image forming apparatus according to claim 1, wherein assuming the current density of the injected current into the single-layer-type electrophotographic photoconductor from the conductive member as Ib (\u03bcAm2) and a current density of an injected current into the single-layer-type electrophotographic photoconductor from the transfer device as It (\u03bcAm2), a value expressed by |IbIt| is set to a value of 2 or more.
3. The image forming apparatus according to claim 1, wherein assuming an absolute value of a current density It (\u03bcAm2) of an injected current into the single-layer-type electrophotographic photoconductor from the transfer device as a value of 316 or more, an absolute value of a transfer memory potential (V) is set to a value of 8 or less.
4. The image forming apparatus according to claim 1, wherein an applied voltage to the conductive member is set to a value of 1100 (V) or more in a DC voltage.
5. The image forming apparatus according to claim 1, wherein the conductive member is formed of a brush-like conductive member.
6. The image forming apparatus according to claim 5, wherein a yarn resistance of a brush which constitutes the conductive member is set to a value of 1\xd71010 (\u03a9\xb7cm) or less.
7. The image forming apparatus according to claim 1, wherein the charging device is a contact-charge-type charging device.
8. The image forming apparatus according to claim 1, wherein an initial charge potential of the single-layer-type electrophotographic photoconductor by the charging device is set to a value of 400 (V) or more.
9. An image forming method which uses an image forming apparatus which sequentially arranges a charging device, a developing device, a transfer device, and a charge eliminating device around a single-layer-type electrophotographic photoconductor, wherein
the single-layer-type electrophotographic photoconductor is charged with a positive polarity by the charging device,
a precharging device having a conductive member is arranged on an upstream side of the charge eliminating device, and
the conductive member is brought into contact with the surface of the single-layer-type electrophotographic photoconductor, and a current density Ib (\u03bcAm2) of an injected current into the single-layer-type electrophotographic photoconductor from the conductive member is set to a value of 700 (\u03bcAm2) or more.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A sheet feeding device comprising:
a sheet container that contains a sheet stack therein;
an outer end part that is detachably attached to the sheet container;
a sheet feeding member to feed the sheet in the sheet container to an outside of the sheet feeding device;
a swing shaft disposed at an upstream side of the sheet container in a sheet feeding direction;
a sheet loading member having a loading surface on which the sheet in the sheet container is loaded, and being supported by the swing shaft to swing according to an amount of sheets loaded on the loading surface;
multiple rotary shafts;
a sheet amount indicator being rotatably supported by one of the rotary shafts, having a contact end that contacts the sheet loading member swinging according to the amount of sheets loaded on the sheet loading member, and having a sheet amount display end disposed at an opposite side of the contact end with one of the rotary shafts in between and moving in a given display range visible from the outside of the sheet feeding device; and
a rotary supporting part supported by a selected one of the multiple rotary shafts disposed at different positions.
2. The sheet feeding device according to claim 1, wherein an angle and direction of slope of the sloped surface with respect to the loading surface is set as the sheet amount display end of the sheet amount indicator moves a whole range of the given display amount between a sheet full state and a sheet empty state of the sheets on the sheet loading member.
3. The sheet feeding device according to claim 1, wherein the outer end part comprises an outer end surface having a display aperture in which the sheet amount display end is moved,
wherein the sheet amount indicator is detachably attached to a corresponding one of the multiple rotary shafts.
4. The sheet feeding device according to claim 1, wherein the outer end part has a display aperture in which the sheet amount display end of the sheet amount indicator is moved, and is detachably attached to the sheet container, and
wherein the sheet amount indicator includes multiple rotary shafts disposed both at the sheet container and the outer end part.
5. The sheet feeding device according to claim 1, wherein the sloped surface is integrally included with the sheet loading member.
6. The sheet feeding device according to claim 1, wherein the sloped surface projects from the sheet loading member to one of an upper side direction, a lower side direction, and an upper and lower side direction.
7. The sheet feeding device according to claim 1, wherein the sloped surface is disposed at a position not to interfere with the sheet on the sheet loading member.
8. The sheet feeding device according to claim 1, wherein the sheet amount indicator is an arm-shaped member having a bend.
9. The sheet feeding device according to claim 1, wherein the outer end part has an interfering part to interfere with attachment or movement of the sheet amount indicator when the sheet amount indicator is fitted to the rotary shaft other than a target rotary shaft.
10. The sheet feeding device according to claim 1, wherein the sheet amount indicator comprises a detecting part body member having the contact end and a display part body having the sheet amount display end to be detachably attached to each other, and
wherein the rotary supporting part is supported by one of the rotary shafts and is included in either one of the detecting part body and the display part body.
11. The sheet feeding device according to claim 10, wherein the detector part body member and the display part body are connected to each other.
12. The sheet feeding device according to claim 1, wherein the sheet feeding device further comprises multiple supported parts disposed at different positions of the sheet amount indicator,
wherein one of the multiple supported parts is supported by the rotary shaft of the sheet amount indicator.
13. The sheet feeding device according to claim 12, wherein the multiple supported parts of the sheet amount indicator have different shapes from each other, and
wherein the sheet amount indicator includes multiple rotary shafts according to the respective shapes of the multiple supported parts.
14. The sheet feeding device according to claim 12, wherein the sheet amount indicator has multiple different contact ends, and
wherein, when one of the multiple different supported parts of the sheet amount indicator is supported by the rotary shaft, one of the multiple different contact ends contacts the sheet loading member.
15. The sheet feeding device according to claim 1, wherein the sheet amount indicator has multiple different contact ends,
wherein the sheet amount indicator is supported by the rotary shaft in one of a normal manner and an upside down manner, and
wherein one of the multiple different contact end contacts the sheet loading member.
16. The sheet feeding device according to claim 1, wherein the outer end part comprises a display aperture through which the sheet amount display end of the sheet amount indicator is visually acknowledged.
17. The sheet feeding device according to claim 16, wherein the display aperture of the outer end part has a sloped surface at an edge of the display aperture, extending wider from an inner side of the sheet container toward an outer side thereof.
18. The sheet feeding device according to claim 16, wherein the display aperture of the outer end part includes a peripheral part and a graduation arranged on the peripheral part to show a remaining amount of sheets in the sheet container.
19. The sheet feeding device according to claim 16, wherein a leading point of the sheet amount display end of the sheet amount indicator remains inside the display aperture of the outer end part.
20. An image forming apparatus comprising:
an image carrier to form an image on a surface thereof; and
the sheet feeding device according to claim 1 to feed a sheet onto which the image is transferred.
21. The sheet feeding device according to claim 1, wherein the sheet loading member has a sloped surface sloped with respect to the loading surface and disposed at a portion where the contact end of the sheet amount indicator contacts the loading surface.
22. The sheet feeding device according to claim 1, wherein the rotary supporting part is rotatably supported to the support shaft attached to the outer end part.
23. The sheet feeding device according to claim 1, wherein the rotary supporting part is rotatably supported to the support shaft attached to the sheet container.