SHEET FEED APPARATUS AND SHEET FEED METHOD

Abstract

Provided is a sheet feed apparatus including: a loading unit loaded with a sheet stack including sheets; a feed unit that comes into contact with a surface of the uppermost sheet of the sheet stack and feeds the sheet in a feed direction; and a separation mechanism that jets out air to sheets to separate the sheets in a height direction, the separation mechanism has a first jetting unit that jets out air to a first region including a downstream end of the uppermost sheet and a second jetting unit that jets out air to a second region of the sheet stack below the first region, the first jetting unit jets out air such that a first jetting direction to the first region varies, and the second jetting unit jets out air in a second jetting direction directed to the second region and set independently of the first jetting direction.

Claims

1. A sheet feed apparatus comprising: a loading unit configured to be loaded with a sheet stack including sheets; a feed unit configured to come into contact with a surface of the uppermost sheet of the sheet stack and feed the sheet in a feed direction; and at least one first separation mechanism configured to jet out air to a plurality of sheets including the uppermost sheet of the sheet stack to separate the plurality of sheets in a height direction, wherein the first separation mechanism has a first jetting unit configured to jet out air to a first region including a downstream end in the feed direction of the uppermost sheet of the sheet stack, and a second jetting unit configured to jet out air to a second region of the sheet stack, the second region being below the first region in the height direction, wherein the first jetting unit jets out air such that a first jetting direction directed to the first region varies, and wherein the second jetting unit jets out air in a second jetting direction directed to the second region and set independently of the first jetting direction.

2. The sheet feed apparatus according to claim 1, wherein the second jetting unit fixes the second jetting direction to a constant direction and jets out air.

3. The sheet feed apparatus according to claim 1, wherein the first jetting unit jets out air such that the first jetting direction oscillates in the height direction, wherein the second jetting unit jets out air such that the second jetting direction oscillates in the height direction, and wherein a first motion direction in the height direction of the tip of the first jetting unit is set to an opposite direction to a second motion direction in the height direction of the tip of the second jetting unit.

4. The sheet feed apparatus according to claim 1, wherein a plurality of first separation mechanisms are arranged at a plurality of positions along a width direction orthogonal to the feed direction of the sheets fed by the feed unit.

5. The sheet feed apparatus according to claim 4, wherein a pair of the first separation mechanisms are arranged at positions symmetrical with respect to the center position in the width direction of the sheet stack.

6. The sheet feed apparatus according to claim 5 further comprising a second separation mechanism configured to jet out air to the plurality of sheets including the uppermost sheet of the sheet stack to separate the plurality of sheets in the height direction, wherein the second separation mechanism is arranged at a more distant position from the center position than the first separation mechanism.

7. The sheet feed apparatus according to claim 1, wherein the first separation mechanism has an air supply path supplied with air, a partition plate that partitions air supplied from the air supply path into the first jetting unit and the second jetting unit at a predetermined position in the height direction, and a deflection plate that causes a flowing direction of air guided to the first jetting unit to vary in the height direction.

8. The sheet feed apparatus according to claim 1, wherein the feed unit has a driving roller, a driven roller, a feed belt stretched around the driving roller and the driven roller, suction holes being formed in the feed belt, and a suction unit configured to suck air through the suction holes formed in the feed belt passing by a position facing the sheet stack.

9. The sheet feed apparatus according to claim 1, wherein when the sheets are viewed in planar view, the first jetting unit jets out air in a direction to an edge arranged at a downstream end in the feed direction of the sheets, the direction being opposite to the feed direction.

10. The sheet feed apparatus according to claim 1, wherein when the sheets are viewed in planar view, the first jetting unit jets out air in a direction to an edge arranged parallel to the feed direction of the sheets, the direction intersecting the feed direction.

11. A sheet feed method for feeding sheets by a sheet feed apparatus, wherein the sheet feed apparatus comprises a loading unit configured to be loaded with a sheet stack including sheets, a feed unit configured to come into contact with a surface of the uppermost sheet of the sheet stack and feed the sheet in a feed direction, and at least one first separation mechanism configured to jet out air to a plurality of sheets including the uppermost sheet of the sheet stack to separate the plurality of sheets in a height direction, and wherein the first separation mechanism has a first jetting unit configured to jet out air to a first region including a downstream end in the feed direction of the uppermost sheet of the sheet stack, and a second jetting unit configured to jet out air to a second region of the sheet stack, the second region being below the first region in the height direction, the sheet feed method comprising: a first jetting step of jetting out air such that a first jetting direction directed from the first jetting unit to the first region varies; a second jetting step of jetting out air in a second jetting direction directed from the second jetting unit to the second region and set independently of the first jetting direction; and a feeding step of feeding the sheet in the feed direction by the feed unit in a state where air is jetted to the first region in the first jetting step and air is jetted to the second region in the second jetting step.

12. The sheet feed method according to claim 11, wherein the second jetting step includes fixing the second jetting direction to a constant direction and jetting out air.

13. The sheet feed method according to claim 11, wherein the first jetting step includes jetting out air such that the first jetting direction oscillates in the height direction, wherein the second jetting step includes jetting out air such that the second jetting direction oscillates in the height direction, and wherein a first motion direction in the height direction of the tip of the first jetting unit is set to an opposite direction to a second motion direction in the height direction of the tip of the second jetting unit.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0037] FIG. 1 is a sectional view illustrating a sheet feed apparatus according to a first embodiment of the present disclosure.

[0038] FIG. 2 is a plan view of the sheet feed apparatus illustrated in FIG. 1 when viewed from above.

[0039] FIG. 3 is a diagram of the sheet feed apparatus illustrated in FIG. 1 when viewed from upstream in a feed direction.

[0040] FIG. 4 is a partial enlarged view of a first separation mechanism illustrated in FIG. 1.

[0041] FIG. 5 is an arrow B-B sectional view of the sheet feed apparatus illustrated in FIG. 3.

[0042] FIG. 6 is a partial enlarged view illustrating a first separation mechanism of a sheet feed apparatus according to a second embodiment of the present disclosure.

DETAILED DESCRIPTION

First Embodiment

[0043] A sheet feed apparatus 100 according to a first embodiment of the present disclosure will be described with reference to the drawings. FIG. 1 is a sectional view illustrating the sheet feed apparatus 100 according to the first embodiment of the present disclosure. FIG. 2 is a plan view of the sheet feed apparatus 100 illustrated in FIG. 1 when viewed from above. FIG. 3 is a diagram of the sheet feed apparatus 100 illustrated in FIG. 1 when viewed from upstream in a feed direction FD. FIG. 1 is an arrow A-A sectional view of the sheet feed apparatus 100 illustrated in FIG. 3.

[0044] As illustrated in FIG. 1, the sheet feed apparatus 100 of the present embodiment includes a loading unit 10, feed units 20, first separation mechanisms 30, second separation mechanisms 40, and a control unit 50. The sheet feed apparatus 100 is an apparatus that causes the feed unit 20 to feed only the uppermost sheet S out of a plurality of sheets S included in a sheet stack St loaded on the loading unit 10 in a one-by-one manner in the feed direction FD.

[0045] The loading unit 10 is a device that is loaded with the sheet stack St including a plurality of sheets S. The sheet stack St is formed of a plurality of sheets S stacked in the height direction HD on a shelf 11. The shelf 11 is moved in the height direction HD by the lift mechanism 12 so that the uppermost sheet S of the sheet stack St comes close to the feed units 20. The lift mechanism 12 is controlled by a control instruction from the control unit 50.

[0046] The feed units 20 each are a device that comes into contact with the front face of the uppermost sheet S of the sheet stack St and feeds the sheet S in the feed direction FD. Each feed unit 20 has a driving roller 21, a driven roller 22, a feed belt 23, and a suction unit 24. The feed belt 23 is a belt stretched around the driving roller 21 and the driven roller 22 and having a plurality of suction holes 23a formed therein. For example, the feed belt 23 is formed of a rubber material.

[0047] As illustrated in FIG. 2, the feed units 20 are arranged at a plurality of positions along the width direction WD. The plurality of feed units 20 are arranged at symmetrical positions (four points of positions in the example illustrated in FIG. 2) with respect to the center position in the width direction WD of the sheet stack St (with respect to a position on an axis X along the feed direction FD). The driving roller 21 generates drive force of rotation in a rotation direction RD. The driving roller 21 is rotated in the rotation direction RD, thereby the drive force is transferred to the feed belt 23, and the feed belt 23 is rotated in the rotation direction RD.

[0048] The suction unit 24 is a device that sucks outside air through the suction holes 23a formed in the feed belt 23 passing by a position facing the sheet stack St. The suction unit 24 sucks outside air through the suction holes 23a, and thereby the uppermost sheet S of the sheet stack St is sucked to the feed belt 23. The sheet S sucked to the feed belt 23 is fed in the feed direction FD by the feed belt 23.

[0049] The first separation mechanisms 30 each are a device that jets out air to a plurality of sheets S including the uppermost sheet S of the sheet stack St to separate the sheets S in the height direction HD. As illustrated in FIG. 2 and FIG. 3, the first separation mechanisms 30 are arranged at a plurality of positions along the width direction WD orthogonal to the feed direction FD of the sheets S fed by the feed units 20. A pair of the first separation mechanisms 30 are each arranged at symmetrical positions with respect to the center position in the width direction WD of the sheet stack St (with respect to a position on the axis X along the feed direction FD).

[0050] FIG. 4 is a partial enlarged view of the first separation mechanism 30 illustrated in FIG. 1. As illustrated in FIG. 4, the first separation mechanism 30 has a first jetting unit 31 and a second jetting unit 32. The first jetting unit 31 jets out air to a first region R1 including the downstream end in the feed direction FD of the uppermost sheet S of the sheet stack St. The second jetting unit 32 jets out air to a second region R2, which is below the first region R1 in the height direction HD, of the sheet stack St.

[0051] For example, the first region R1 is a region in a range of 10 mm or greater and 20 mm or less in the height direction HD from the surface on the sheet stack St side of the feed belt 23. For example, the second region R2 is a region in a range of 5 mm or greater and 10 mm or less from the lower end in the height direction HD of the first region R1.

[0052] As illustrated in FIG. 4, the first separation mechanism 30 has an air supply path 30A, a partition plate 30B, a deflection plate 30C, and a swing mechanism 30D. The air supply path 30A is a flow path in which air is supplied along the flowing direction indicated by arrows in FIG. 4. The partition plate 30B is a plate-like member that partitions the air supplied from the air supply path 30A into the first jetting unit 31 and the second jetting unit 32 at a predetermined position in the height direction HD.

[0053] The symbol JD1 illustrated in FIG. 2 indicates a direction of air jetted out of the first separation mechanism 30 when the sheets S are viewed in planar view from above to below in the height direction HD. As illustrated in FIG. 2, the first jetting unit 31 and the second jetting unit 32 of the first separation mechanism 30 jet out air in a jetting direction JD1, which is a direction opposite to the feed direction FD, to an edge Se1 arranged at the downstream end in the feed direction FD of the sheets S when the sheets S are viewed in planar view.

[0054] Note that, as a modified example for the present embodiment, the first separation mechanisms 30 illustrated by dotted lines in FIG. 2 may be employed instead of the first separation mechanisms 30 illustrated by solid lines in FIG. 2. As illustrated in FIG. 2, the first separation mechanism 30 of the modified example illustrated in the dotted lines jets out air in a jetting direction JD2, which intersects the feed direction FD (for example, the direction orthogonal thereto), to an edge Se2 arranged parallel to the feed direction FD of the sheets S when the sheets S are viewed in planar view. Further, as a modified example for the present embodiment, the first separation mechanism 30 illustrated by the dotted lines in FIG. 2 may be separately provided in addition to the first separation mechanisms 30 illustrated by the solid lines in FIG. 2.

[0055] The deflection plate 30C is a device that causes a flowing direction of air guided from the air supply path 30A to the first jetting unit 31 to vary in the height direction HD. Air blown from a fan (not illustrated) is guided to the air supply path 30A. The deflection plate 30C is swung in a range of an angle about a swing shaft 30E by the swing mechanism 30D. The deflection plate 30C swings the first jetting direction in which the first jetting unit 31 jets out air between the direction ID11 indicated by the solid line and the direction ID12 indicated by the dotted line.

[0056] The swing mechanism 30D is controlled by a control instruction from the control unit 50. The control unit 50 sets a swing cycle at which the deflection plate 30C is swung by the swing mechanism 30D to a range of 0.2 seconds or longer and 0.3 seconds or shorter, for example.

[0057] When the first jetting direction is ID12, the deflection plate 30C is arranged in a position indicated by the dotted lines in FIG. 4. Herein, the first jetting direction is a direction extending in an airflow center line on which the flow speed of air jetted out of the first jetting unit 31 is the highest.

[0058] The first jetting unit 31 jets out air such that the first jetting direction to the first region R1 of the sheet stack St varies between the directions ID11 and ID12 (first jetting step). The second jetting unit 32 jets out air such that the second jetting direction to the second region R2 of the sheet stack St is fixed in a constant direction of ID2 (second jetting step). The feed unit 20 feeds the sheets S in the feed direction FD in a state where air is jetted out of the first jetting unit 31 to the first region R1 and air is jetted out of the second jetting unit 32 to the second region R2 (feeding step). In such a way, the second jetting direction ID2 is a direction set independently of the first jetting direction that varies between the directions ID11 and ID12.

[0059] The second separation mechanisms 40 each are a device that jets out air to a plurality of sheets S including the uppermost sheet S of the sheet stack St to separate the sheets S in the height direction HD. As illustrated in FIG. 2 and FIG. 3, the second separation mechanisms 40 are arranged at a plurality of positions along the width direction WD orthogonal to the feed direction FD of the sheets S fed by the feed units 20.

[0060] Four second separation mechanisms 40, with two of which being paired, are arranged at symmetrical positions with respect to the center position in the width direction WD of the sheet stack St (with respect to a position on the axis X along the feed direction FD). The second separation mechanisms 40 are arranged at more distant positions from the center position in the width direction WD of the sheet stack St than the first separation mechanisms 30.

[0061] FIG. 5 is an arrow B-B sectional view of the sheet feed apparatus 100 illustrated in FIG. 3. As illustrated in FIG. 5, the second separation mechanisms 40 jet out air to a third region R3 including the downstream end in the feed direction FD of the uppermost sheet S of the sheet stack St. Each second separation mechanism 40 has an air supply path 40A and a jetting unit 40B. Air blown from a fan (not illustrated) is guided to the air supply path 40A. The second separation mechanism 40 jets, out of the jetting unit 40B, the air supplied in the direction indicated by arrows in FIG. 5 from the air supply path 40A and guides the air to the third region R3.

[0062] The effects and advantages achieved by the sheet feed apparatus 100 of the present embodiment described above will be described.

[0063] According to the sheet feed apparatus 100 of the present embodiment, a plurality of sheets S including the uppermost sheet S of the sheet stack St are separated in the height direction HD by air jetted out of the first separation mechanisms 30. Since the first jetting direction of air jetted to the first region R1 of the sheet stack St out of the first jetting unit 31 varies, even when separation between the sheets S adjacent to each other in the first region R1 of the sheet stack St is less likely to occur, air can be reliably guided between these sheets S to be separated in the height direction.

[0064] Further, according to the sheet feed apparatus 100 of the present embodiment, the second jetting direction of air jetted out of the second jetting unit 32 to the second region R2 of the sheet stack St is fixed to a constant direction. Thus, even when the sheets S are pressed downward in the height direction HD by the air jetted out of the first jetting unit 31, the sheet S is pushed up toward the first region R1 by the air jetted out of the second jetting unit 32. This prevents the sheet S from being excessively pressed downward in the height direction HD by the air jetted out of the first jetting unit 31 and thus prevents an increase in the distance in the height direction HD from the pressed sheet S to the uppermost sheet S, and the time required for the pressed sheet S to move to the position of the uppermost sheet S is shortened. It is therefore possible to cause the sheets S stacked into the sheet stack St to be reliably separated one by one and feed the separated sheet S while increasing the feed speed of the sheets S.

[0065] According to the sheet feed apparatus 100 of the present embodiment, a plurality of first separation mechanisms 30 arranged at a plurality of positions in the width direction WD of the sheets S jet out air to a plurality of positions in the width direction WD of the plurality of sheets S including the uppermost sheet S of the sheet stack St, and thereby the sheets S can be reliably separated in the height direction HD.

[0066] According to the sheet feed apparatus 100 of the present embodiment, a pair of the first separation mechanisms 30 arranged at positions symmetrical with respect to the center position in the width direction WD of the sheet stack St jet out air to a plurality of positions in the width direction WD of the plurality of sheets S including the uppermost sheet S of the sheet stack St, and thereby the sheets S can be reliably separated in the height direction HD.

[0067] According to the sheet feed apparatus 100 of the present embodiment, the second separation mechanism 40 arranged at a more distant position from the center position in the width direction WD of the sheet stack St than the first separation mechanism 30 can reliably separate the region on the end side in the width direction WD of the sheet stack St into each single sheet in the height direction HD.

[0068] According to the sheet feed apparatus 100 of the present embodiment, air supplied from the air supply path 30A can be separated in the height direction HD by the partition plate 30B, air present above in the height direction HD can be jetted out of the first jetting unit 31 to the first region R1, and air present below in the height direction HD can be jetted out of the second jetting unit 32 to the second region R2. Further, the flowing direction of air guided to the first jetting unit 31 can be changed in the height direction HD by the deflection plate 30C, and the air can be jetted out of the first jetting unit 31.

[0069] According to the sheet feed apparatus 100 of the present embodiment, the uppermost sheet S of the sheet stack St separated from the first separation mechanism 30 is sucked to the feed belt 23 by air sucked by the suction unit 24 and thereby can be fed one by one in the feed direction FD.

[0070] According to the sheet feed apparatus 100 of the present embodiment, air is jetted in the jetting direction JD1, which is a direction opposite to the feed direction FD, to the edge Se1 arranged at the downstream end in the feed direction FD of the sheet S, and thereby the edge Se1 arranged at the downstream end in the feed direction FD of the sheet S can be suitably separated from the remaining sheets S.

[0071] According to the sheet feed apparatus 100 of the present embodiment, air is jetted in a direction, which intersects the feed direction FD, to the edge Se2 arranged parallel to the feed direction FD of the sheet S, and thereby air can be reliably guided between the sheets S to be separated in the height direction HD while the first separation mechanism 30 is arranged at a position distant from a region supplied with the sheets S.

Second Embodiment

[0072] Next, a sheet feed apparatus 100A according to a second embodiment of the present disclosure will be described with reference to the drawings. FIG. 6 is a partial enlarged view illustrating the first separation mechanism 30 of the sheet feed apparatus 100A according to the second embodiment of the present disclosure.

[0073] In the first separation mechanism 30 of the sheet feed apparatus 100 according to the first embodiment, the second jetting unit 32 fixes the second jetting direction ID2 to a constant direction and jets out air. In contrast, in the first separation mechanism 30 of the sheet feed apparatus 100A according to the present embodiment, the second jetting unit 32 jets air such that the second jetting direction oscillates in the height direction.

[0074] The first separation mechanism 30 of the present embodiment has a partition plate 30B that causes the flowing direction of air guided from the air supply path 30A to the second jetting unit 32 to vary in the height direction HD. The partition plate 30B is swung in a range of an angle 2 about a swing shaft 30Ba by a swing mechanism (not illustrated). The partition plate 30B swings the second jetting direction in which the second jetting unit 32 jets out air between the direction ID21 indicated by the solid line and the direction ID22 indicated by the dotted line. The second jetting unit 32 jets out air such that the second jetting direction oscillates in the height direction HD between the directions ID21 and ID22.

[0075] The first separation mechanism 30 of the present embodiment has a deflection plate 30C that causes the flowing direction of air guided from the air supply path 30A to the first jetting unit 31 to vary in the height direction HD. The deflection plate 30C is swung in a range of an angle 1 about a swing shaft 30E by the swing mechanism 30D. The deflection plate 30C swings the first jetting direction in which the first jetting unit 31 jets out air between the direction ID11 indicated by the solid line and the direction ID12 indicated by the dotted line. The first jetting unit 31 jets out air such that the first jetting direction oscillates in the height direction HD between the directions ID11 and ID12.

[0076] In the first separation mechanism 30 of the present embodiment, the first motion direction in the height direction HD of the tip of the first jetting unit 31 (the end on the sheet stack St side of the deflection plate 30C) is set to the opposite direction to the second motion direction in the height direction HD of the tip of the second jetting unit 32 (the end on the sheet stack St side of the partition plate 30B).

[0077] When the first jetting direction of the first jetting unit 31 is moved upward in the height direction HD from ID11 to ID12, the second jetting direction of the second jetting unit 32 is moved downward in the height direction HD from ID21 to ID22. Further, when the first jetting direction of the first jetting unit 31 is moved downward in the height direction HD from ID12 to ID11, the second jetting direction of the second jetting unit 32 is moved upward in the height direction HD from ID22 to ID21.

[0078] In the present embodiment, the first region R1 in which the first jetting unit 31 jets out air to the sheet stack St and the second region R2 in which the second jetting unit 32 jets out air to the sheet stack St partially overlap with each other in the height direction HD. The second jetting unit 32 of the present embodiment can ensure a wider second region R2 in the height direction HD than the second jetting unit 32 of the first embodiment.

[0079] According to the sheet feed apparatus 100A of the present embodiment, since the first motion direction is set to the opposite direction to the second motion direction, a state where air jetted out of the first jetting unit 31 and air jetted out of the second jetting unit 32 are concentrated in regions close to each other in the height direction HD and a state where air jetted out of the first jetting unit 31 and air jetted out of the second jetting unit 32 are distributed into regions spaced apart from each other in the height direction HD are alternatingly repeated. This can facilitate establishment of a state where a plurality of sheets S including the uppermost sheet S of the sheet stack St are separated in the height direction HD by the air jetted out of the first separation mechanism 30.

[0080] Although the second jetting unit 32 jets out air such that the second jetting direction oscillates in the height direction in the sheet feed apparatus 100A of the second embodiment of the present disclosure described above, other forms may be employed. For example, the second jetting unit 32 may fix the second jetting direction at a particular angle between the directions ID21 and ID22 and jet out air in a constant direction.