MEDIUM FEEDING APPARATUS AND IMAGE FORMING APPARATUS

Abstract

A medium feeding apparatus includes a main body, and a medium placing unit at least a part of which can be housed in the main body. The medium placing unit includes a first placing unit held by the main body in such a manner that the first placing unit is shiftable between a housed position where at least one of the first placing unit is housed in the main body and a placing position where the medium can be placed on the first placing unit, a second placing unit has a first shifting condition where the medium can be placed on the first and second placing units and a second shifting condition where the second placing unit is overlapped with the first placing unit, and an auxiliary member disposed on a boundary between the first placing unit and the second placing unit when the second placing unit is in the first shifting condition.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

In the attached drawings:

FIG. 1 is a perspective view showing an external shape of a medium feeding apparatus according to Embodiment 1 of the present invention;

FIG. 2 is a schematic view showing a main part of an image forming apparatus using the medium feeding apparatus according to Embodiment 1 of the present invention;

FIG. 3A is a simplified view showing a relationship among an outer cover portion, a sheet placing plate, a first auxiliary tray and an auxiliary placing plate (when assembled) according to Embodiment 1 of the present invention;

FIGS. 3B through 3G show structures for mounting respective parts;

FIG. 4 is a sectional view showing a sheet supply tray in a housed position in which the sheet supply tray is folded to a main body side of the medium feeding apparatus and is locked by a locking portion;

FIGS. 5A through 5G are schematic views showing an operation to move the sheet supply tray to the housed position in the main body of the medium feeding apparatus according to Embodiment 1 of the present invention in the order of the operation;

FIG. 6 is a perspective view showing a modification of a sheet supply tray according to Embodiment 1 of the present invention;

FIG. 7A is a simplified view showing a relationship among an outer cover portion, a sheet placing plate, a first auxiliary tray and an auxiliary placing plate (when assembled) according to Embodiment 2 of the present invention;

FIG. 7B is a partial view showing a structure of a rotation supporting portion of the sheet supply tray according to Embodiment 2 of the present invention;

FIG. 8 is a side view showing a relationship among heights of respective placing surfaces when the sheet placing plate is in a rotational reference position and when the first auxiliary tray and the auxiliary placing plate are in fully-opening conditions;

FIGS. 9A through 9E are schematic views showing an operation to move the sheet supply tray to the housed position in the main body of the medium feeding apparatus according to Embodiment 2 of the present invention in the order of the operation;

FIGS. 10A through 10E are schematic views showing the respective steps of FIGS. 9A through 9E, as seen from the backside of the sheet placing surface (i.e., as seen from the outer cover portion side);

FIG. 11A is a simplified view showing a relationship among an outer cover portion, a sheet placing plate, a first auxiliary tray and an auxiliary placing plate (when assembled) according to Embodiment 3 of the present invention;

FIG. 11B is a partial view showing a structure of a rotation supporting portion of a sheet supply tray according to Embodiment 3 of the present invention;

FIG. 12 is a side view showing respective parts when the sheet placing plate is in a reference rotational position and when the first auxiliary tray and the auxiliary placing plate are in fully-opening conditions;

FIGS. 13A through 13D are schematic views showing an operation to move the sheet supply tray to the housed position in the main body of the medium feeding apparatus according to Embodiment 3 of the present invention in the order of the operation;

FIG. 14A is a sectional view showing a structure of a sheet supply tray according to Embodiment 4 of the present invention;

FIG. 14B is a partial view of a part indicated by a dashed two-dotted line in FIG. 14A showing a structure of a sheet supply tray according to Embodiment 4 of the present invention;

FIG. 15A is a sectional view showing the sheet supply tray according to Embodiment 4 of the present invention in a state where the first auxiliary tray is lifted in a direction shown by the arrow A in FIG. 14A by an angle of 90 degrees or more;

FIG. 15B is a partial view of a part indicated by a dashed two-dotted line in FIG. 15A showing a structure of a sheet supply tray according to Embodiment 4 of the present invention;

FIG. 16A is a simplified view showing a relationship among an outer cover portion, a sheet placing plate, a first auxiliary tray and an auxiliary placing plate (when assembled) according to Embodiment 5 of the present invention, and

FIG. 16B is a partial view showing a part of the sheet supply tray in which a roller is provided.

Claims

1. A medium feeding apparatus comprising: a main body, anda medium placing unit at least a part of which can be housed in said main body,wherein said medium placing unit includes:a first placing unit held by said main body in such a manner that said first placing unit is shiftable between a housed position where said at least a part of said first placing unit is housed in said main body and a medium placing position where a medium can be placed on said first placing unit;a second placing unit having a first shifting condition where said medium can be placed on said first and second placing units and a second shifting condition where said second placing unit is overlapped with said first placing unit, andan auxiliary member disposed on a boundary between said first placing unit and said second placing unit when said second placing unit is on said first shifting condition.

2. The medium feeding apparatus according to claim 1, wherein said first placing unit includes: a holding member movable between said housed position and said medium placing position, anda medium placing portion shiftably held by said holding member and having a placing surface on which said medium can be placed,wherein, when said holding member is in said medium placing position, said placing surface is adjacent to said main body and said medium is placed on said placing surface.

3. The medium feeding apparatus according to claim 1, wherein said first placing unit has a placing surface on which said medium can be placed, and wherein an end portion of said auxiliary member is rotatably held by said second placing unit, and the other end portion of said auxiliary member moves on said placing plate in accordance with a shifting of said second placing unit.

4. The medium feeding apparatus according to claim 1, wherein said first placing unit and said auxiliary member have engaging portions that engage each other when said second placing unit is in said first shifting condition.

5. The medium feeding apparatus according to claim 3, further comprising an urging member that urges said other end of said auxiliary member against said placing surface.

6. The medium feeding apparatus according to claim 3, further comprising a rotating member provided on said other end of said auxiliary member, said rotating member rotating on said placing surface.

7. The medium feeding apparatus according to claim 1, wherein said auxiliary member is shiftably held by said first placing unit.

8. The medium feeding apparatus according to claim 2, wherein said auxiliary member is shiftably held by said holding member.

9. The medium feeding apparatus according to claim 8, wherein said auxiliary member is shiftable between a housed position in which said auxiliary member faces a surface of said holding member opposite to a surface facing said medium placing portion and a medium placing position in which said auxiliary member is disposed on a boundary of said medium placing portion and said second placing unit.

10. The medium feeding apparatus according to claim 1, wherein said auxiliary member includes a sheet member, wherein one end of said sheet member is fixed to said second placing unit, and the other end of said sheet member is wound around a winding portion rotatably held on said first placing unit and applied with a rotational force in one direction so that said sheet member is kept tensioned.

11. An image forming apparatus including said medium feeding apparatus according to claim 1.