U.S. patent application number 14/851381 was filed with the patent office on 2016-03-31 for paper sheet feeding apparatus.
The applicant listed for this patent is Kabushiki Kaisha Toshiba. Invention is credited to Atsushi Ina, Junichi Inoue, Takahiro Suzuki.
Application Number | 20160090249 14/851381 |
Document ID | / |
Family ID | 54014671 |
Filed Date | 2016-03-31 |
United States Patent
Application |
20160090249 |
Kind Code |
A1 |
Suzuki; Takahiro ; et
al. |
March 31, 2016 |
PAPER SHEET FEEDING APPARATUS
Abstract
A paper sheet feeding apparatus according to an embodiment
includes a first feeding tray 210, a pickup unit 150, a second
feeding tray 310, an air blow unit 130, a status sensor 140, and a
controller 100. The first feeding tray 210 and the second feeding
tray 310 respectively feed a batch of sheets to the pickup unit
150. The air blow unit 130 blows air to loosen an upper part of the
batch of sheets. The status sensor 140 detects sparseness value of
the upper part of the batch of sheets. The controller 100 makes the
batch of sheets on the first feeding tray 210 to fall on top of
that of the second feeding tray 310 when switching the feeding tray
in charge of feeding the sheets from the first feeding tray 210 to
the second feeding tray 310.
Inventors: |
Suzuki; Takahiro; (Tokyo,
JP) ; Inoue; Junichi; (Kanagawa, JP) ; Ina;
Atsushi; (Saitama, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Kabushiki Kaisha Toshiba |
Tokyo |
|
JP |
|
|
Family ID: |
54014671 |
Appl. No.: |
14/851381 |
Filed: |
September 11, 2015 |
Current U.S.
Class: |
271/9.08 |
Current CPC
Class: |
B65H 2553/414 20130101;
B65H 1/263 20130101; B65H 2513/40 20130101; B65H 1/30 20130101;
B65H 7/04 20130101; B65H 2513/40 20130101; B65H 2515/60 20130101;
B65H 2701/1912 20130101; B65H 2515/60 20130101; B65H 3/48 20130101;
B65H 2515/12 20130101; B65H 3/0883 20130101; B65H 2515/12 20130101;
B65H 2220/01 20130101; B65H 2220/02 20130101; B65H 2220/03
20130101 |
International
Class: |
B65H 1/28 20060101
B65H001/28; B65H 7/02 20060101 B65H007/02; B65H 7/20 20060101
B65H007/20; B65H 1/26 20060101 B65H001/26; B65H 3/08 20060101
B65H003/08 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 30, 2014 |
JP |
2014-202634 |
Claims
1. A paper sheet feeding apparatus, comprising: a first feeding
tray configured to support and feed a batch of sheets, said first
feeding tray movable in a vertical direction; a second feeding tray
configured to support and feed a batch of sheets, said second
feeding tray movable in a vertical direction; a pickup unit
configured to pick up sheets, arranged above the first feeding tray
or the second feeding tray in charge of feeding; an air blow unit
configured to blow air towards an upper part of the batch of sheets
on the first feeding tray or the second feeding tray in charge of
feeding from a side of the upper part of the batch of sheets; a
status sensor configured to detect a sparseness value of the upper
part of the batch of sheets loosened by the air blow unit; and a
controller configured to control the vertical movement of the first
feeding tray or the second feeding tray in charge of feeding so
that the sparseness value of the upper part of the batch of sheets
stays within an upper limit sparseness value and a lower limit
sparseness value that is suitable for picking up a sheet from the
batch of sheets; wherein the first feeding tray is movable in a
direction perpendicular to the vertical direction after making the
first feeding tray ascend until the status sensor detects the upper
limit sparseness value, such that the batch of sheets on the first
feeding tray falls on top of the batch of sheets on the second
feeding tray.
2. A paper sheet feeding apparatus according to claim 1, wherein
the controller is configured to move the first feeding tray in the
perpendicular direction so that a distance d is greater than a
margin D, wherein the distance d is a distance between a position
of the first feeding tray when reaching the upper limit sparseness
value and a position of the first feeding tray when reaching the
lower limit sparseness value, and wherein the margin D is a
distance the batch of sheets on the first feeding tray falls on top
of the batch of sheets on the second feeding tray when the first
feeding tray moves perpendicularly from the vertical direction.
3. A paper sheet feeding apparatus according to claim 2, wherein
the controller elevates the second feeding tray while moving the
first feeding tray perpendicularly from the vertical direction.
4. A paper sheet feeding apparatus according to claim 1, wherein
the first feeding tray and the second feeding tray configure a
meshing structure in a plane perpendicular to the vertical
direction; and wherein the controller moves the first feeding tray
downwards below the second feeding tray after the first feeding
tray is moved perpendicularly from the vertical direction, and then
elevates the first feeding tray to a common plane as the second
feeding tray such that the batch of sheets on the second feeding
tray is transferred to the first feeding tray.
5. A paper sheet feeding apparatus according to claim 2, wherein
the first feeding tray and the second feeding tray configure a
meshing structure in a plane perpendicular to the vertical
direction; and wherein the controller moves the first feeding tray
downwards below the second feeding tray after the first feeding
tray is moved perpendicularly from the vertical direction, and then
elevates the first feeding tray to a common plane as the second
feeding tray such that the batch of sheets on the second feeding
tray is transferred to the first feeding tray.
6. A paper sheet feeding apparatus according to claim 3, wherein
the first feeding tray and the second feeding tray configure a
meshing structure in a plane perpendicular to the vertical
direction; and wherein the controller moves the first feeding tray
downwards below the second feeding tray after the first feeding
tray is moved perpendicularly from the vertical direction, and then
elevates the first feeding tray to a common plane as the second
feeding tray such that the batch of sheets on the second feeding
tray is transferred to the first feeding tray.
7. A paper sheet feeding apparatus according to claim 1, wherein
the controller elevates the first feeding tray or the second
feeding tray in charge of feeding when the status sensor detects
the lower limit sparseness value, and stops the elevation of the
first feeding tray or the second feeding tray in charge of feeding
when the status sensor detects the upper limit sparseness
value.
8. A paper sheet feeding apparatus according to claim 2, wherein
the controller elevates the first feeding tray or the second
feeding tray in charge of feeding when the status sensor detects
the lower limit sparseness value, and stops the elevation of the
first feeding tray or the second feeding tray in charge of feeding
when the status sensor detects the upper limit sparseness
value.
9. A paper sheet feeding apparatus according to claim 3, wherein
the controller elevates the first feeding tray or the second
feeding tray in charge of feeding when the status sensor detects
the lower limit sparseness value, and stops the elevation of the
first feeding tray or the second feeding tray in charge of feeding
when the status sensor detects the upper limit sparseness
value.
10. A paper sheet feeding apparatus according to claim 4, wherein
the controller elevates the first feeding tray or the second
feeding tray in charge of feeding when the status sensor detects
the lower limit sparseness value, and stops the elevation of the
first feeding tray or the second feeding tray in charge of feeding
when the status sensor detects the upper limit sparseness
value.
11. A paper sheet feeding apparatus according to claim 5, wherein
the controller elevates the first feeding tray or the second
feeding tray in charge of feeding when the status sensor detects
the lower limit sparseness value, and stops the elevation of the
first feeding tray or the second feeding tray in charge of feeding
when the status sensor detects the upper limit sparseness
value.
12. A paper sheet feeding apparatus according to claim 6, wherein
the controller elevates the first feeding tray or the second
feeding tray in charge of feeding when the status sensor detects
the lower limit sparseness value, and stops the elevation of the
first feeding tray or the second feeding tray in charge of feeding
when the status sensor detects the upper limit sparseness value.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This Application is based upon and claims the benefit of
priority from the prior Japanese Patent Application No.
JP2014-202634, filed Sep. 30, 2014; the entire contents of which
are incorporated herein by reference.
FIELD
[0002] Embodiments described herein relate generally to a paper
sheet feeding apparatus.
BACKGROUND
[0003] A paper sheet feeding apparatus is equipped in, e.g., a
banknote processing machine that inspects and sorts paper sheets
such as banknotes. The existing paper sheet feeding apparatus feeds
sheets to a pickup unit, which picks up sheets one by one from a
batch of sheets and sends them out downstream at a certain
interval, by using two feeding trays. Before all the sheets stacked
on one of the feeding trays that is in charge of feeding the sheets
then (here, the feeding tray in charge will be referred to as "the
upper feeding tray") have been picked up, another batch of sheets
is additionally supplied to the other feeding tray that is
positioned below the upper feeding tray then (here, the other
feeding tray will be referred to as "the lower feeding tray"), and
the lower feeding tray is elevated to be on standby directly below
the upper feeding tray.
[0004] Then the upper feeding tray is moved perpendicularly from
the vertical direction, and the remaining sheets stacked on the
upper feeding tray are dropped by the force of gravity onto the
additionally supplied batch of sheets on the lower feeding tray. By
doing so, the batch of sheets on the lower feeding tray and the
remaining sheets stacked on the upper feeding tray integrate as one
batch of sheets. Then the lower feeding tray takes over the feeding
of the sheets to the pickup unit.
[0005] In the vicinity of an area below the pickup unit, an air
blow unit that blows air towards the side of the upper part of the
batch of sheets is equipped. The pickup unit sucks and picks up the
sheets one by one from the cluster of sheets in the upper part of
the batch of sheets loosened by the blowing of the air.
[0006] However, there is a gap between the top part of the dropped
stacked sheets and the pickup unit when the remaining sheets
stacked on the upper feeding tray are dropped onto the batch of
sheets on the lower feeding tray. When the gap is too large, the
air blows through, above the top part of the dropped stacked
sheets. In such state, the sheets cannot be properly picked up by
the pickup unit. When the lower feeding tray, now with the
integrated batch of sheets, is elevated to fill the gap, the
uppermost sheet would be blown away by the blowing air.
[0007] When the air blow is stopped to avoid such state, a certain
amount of time would be required to start the next cycle of the
pickup operation. As a result, the feeding by the paper sheet
feeding apparatus would be paused, and thus the throughput of the
paper sheet feeding apparatus decreases.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a perspective view showing a paper sheet feeding
apparatus according to an embodiment;
[0009] FIGS. 2A and 2B are a schematic top view and a schematic
front view showing the paper sheet feeding apparatus according to
the embodiment;
[0010] FIG. 3 is a schematic top view showing a meshing structure
of feeding trays according to the embodiment;
[0011] FIG. 4 is a block diagram schematically showing the paper
sheet feeding apparatus according to the embodiment;
[0012] FIG. 5 is a schematic front view for explaining an
additional supply operation according to the embodiment;
[0013] FIG. 6 is a schematic front view for explaining the
additional supply operation according to the embodiment;
[0014] FIG. 7 is a schematic front view for explaining the
additional supply operation according to the embodiment;
[0015] FIG. 8 is a schematic front view for explaining the
additional supply operation according to the embodiment;
[0016] FIG. 9 is a schematic front view for explaining a takeover
operation according to the embodiment;
[0017] FIG. 10 is a schematic front view for explaining the
takeover operation according to an embodiment;
[0018] FIG. 11 is a schematic front view for explaining the
takeover operation according to the embodiment;
[0019] FIGS. 12A and 12B are schematic front views for explaining a
relationship between a sparseness value of sheets and a position of
the feeding tray according to the embodiment;
[0020] FIG. 13 is a flowchart showing the whole operation of the
paper sheet feeding apparatus according to the embodiment;
[0021] FIG. 14 is a flowchart showing an initial setup operation of
the paper sheet feeding apparatus according to the embodiment;
[0022] FIG. 15 is a flowchart showing a feed operation of the paper
sheet feeding apparatus according to the embodiment;
[0023] FIG. 16 is a flowchart showing the additional supply
operation of the paper sheet feeding apparatus according to the
embodiment;
[0024] FIG. 17 is a flowchart showing the takeover operation of the
paper sheet feeding apparatus according to the embodiment;
DETAILED DESCRIPTION
[0025] A paper sheet feeding apparatus according to an embodiment
includes a first feeding tray 210, a pickup unit 150, a second
feeding tray 310, an air blow unit 130, a status sensor 140, and a
controller 100. The first feeding tray 210 is configured to support
and feed a batch of sheets, and arranged to be movable in a
vertical direction and in a direction perpendicular to the vertical
direction. The pickup unit 150 is configured to pick up sheets, and
arranged above the first feeding tray 210. The second feeding tray
310 is configured to support and feed a batch of sheets, and
arranged below the first feeding tray 210 to be movable in a
vertical direction. The air blow unit 130 is configured to blow air
towards an upper part of the batch of sheets on the first feeding
tray 210 or the second feeding tray 310 from a side of the upper
part of the batch of sheets. The status sensor 140 is configured to
detect a sparseness value of the upper part of the batch of sheets
loosened by the air blow unit 130 by detecting at least two
different values including an upper limit sparseness value suitable
for picking up sheet, indicating high density, and a lower limit
sparseness value suitable for picking up sheet, indicating low
density. The controller 100 is configured to make the batch of
sheets on the first feeding tray 210 to fall on top of the batch of
sheets on the second feeding tray 310 when switching the feeding
tray in charge of feeding the sheets from the first feeding tray
210 to the second feeding tray 310, by moving the first feeding
tray 210 perpendicularly from the vertical direction after making
the first feeding tray 210 ascend until the status sensor 140
detects the upper limit sparseness value.
[0026] Hereinafter, a paper sheet feeding apparatus of an
embodiment will be described with reference to the drawings.
[0027] First, the setup of the paper sheet feeding apparatus of the
embodiment will be described in detail. FIG. 1 is a perspective
view showing the paper sheet feeding apparatus according to the
embodiment. FIGS. 2A and 2B are a schematic top view and a
schematic front view showing the paper sheet feeding apparatus
according to the embodiment. Note that in FIGS. 2A and 2B, only a
first feeding tray 210 is shown and a second feeding tray 310 is
omitted.
[0028] According to the embodiment, the paper sheet feeding
apparatus has a first feeding tray 210 which supports a first batch
of sheets 120, comprised of stacked sheets. The first feeding tray
210 is installed against a base 160 of the paper sheet feeding
apparatus body, in a way so that it is movable in a vertical
direction. The first feeding apparatus is also movable
perpendicularly from the vertical direction.
[0029] The first feeding tray 210 has a first sheet sensor 290,
which detects whether or not a sheet exists on the first feeding
tray 210. The first feeding tray 210 also has a first proximity
sensor 170 on its underside, which detects whether or not a second
batch of sheets 220 (later to be described) placed on a second
feeding tray 310 (later to be described) has approached the first
feeding tray 210 by a certain distance.
[0030] Above the first feeding tray 210, there is a pickup unit
150, which picks up sheets one by one from the top of the first
batch of sheets 120 fed by the first feeding tray 210, and sends
them to a conveyance path. The pickup unit 150 uses negative
pressure to pick up sheets by sucking the sheet lying on the
uppermost surface of the first batch of sheets 120. Then the pickup
unit 150 moves leftwards in FIG. 1 and hands out the sheet that it
picked up to the conveyance path. Note that the pickup unit 150 may
be embodied in other forms, e.g., a rotating suction pickup
system.
[0031] In the vicinity of an area below the pickup unit 150 on the
opposite side to the base 160, that is, in the direction coming out
of the page in FIG. 1, there is an air blow unit 130. The air blow
unit 130 loosens the cluster of sheets in the upper part of the
first batch of sheets 120 by blowing air towards it from its side.
The things written in this paragraph apply for the later described
second batch of sheets 220 as well.
[0032] Opposite to the air blow unit 130, that is, on the side
where the base 160 is, there is a status sensor 140. The status
sensor 140 detects whether or not the upper part of the first batch
of sheets 120 is at a dense state or at a sparse state.
[0033] The status sensor 140 is, e.g., a reflection-type optical
sensor. A reflection-type optical sensor reflects more light when
the cluster of sheets is at a dense state, and it reflects less
light when the cluster of sheets is at a sparse state. The status
sensor 140 outputs the value of the measured amount of the
reflection light. Thus, the output value and the sparseness of the
sheets are in an almost linear correlation.
[0034] Below the first feeding tray 210, a second feeding tray 310
which supports a second batch of sheets 220 is installed against
the base 160 in a way so that it is movable in a vertical
direction. The second feeding tray 310 has a second sheet sensor
390, which detects whether or not a sheet exists on the second
feeding tray 310. The second feeding tray 310 also has a second
proximity sensor 270 on its side, which detects whether or not the
first feeding tray 210 is at a common plane as the second feeding
tray 310.
[0035] On the base 160, there is a limit sensor 180 which detects
an elevation limit, which is the highest position that the first
feeding tray 210 can ascend to. When there is no more sheet to be
additionally supplied, the first feeding tray 210 ascends until the
limit sensor 180 detects the first feeding tray 210 to have reached
the elevation limit. After the first feeding tray 210 reaches the
elevation limit, the first feeding tray 210 stops ascending, and
the first feeding tray 210 continues feeding. When all the
remaining sheets on the first feeding tray 210 have been picked up
by the pickup unit 150, the first sheet sensor 290 turns `On`,
meaning that it detects no existence of sheets left. The things
written here in this paragraph apply for the second feeding tray
310 as well.
[0036] The first sheet sensor 290 and the second sheet sensor 390
are, e.g., a pair of transmission-type optical sensor. A light
projecting LED and a light receiving sensor are placed facing each
other with the batch of sheets on the feeding tray in between. When
there are sheets on the feeding tray, the projected light would be
blocked and thus the sheet sensor would be in an `Off` state.
[0037] Here, a meshing structure of the feeding trays according to
the embodiment will be described in detail. FIG. 3 is a schematic
top view showing the meshing structure of the first feeding tray
210 and the second feeding tray 310 according to the
embodiment.
[0038] The first feeding tray 210 and the second feeding tray 310
configure a meshing structure. As shown in FIG. 3, the first
feeding tray 210 is shaped like the alphabet `E`. The second
feeding tray 310 is placed closer to the base 160 than the first
feeding tray 210, and it has protruding parts where the first
feeding tray 210 has recessed parts, and recessed parts where the
first feeding tray 210 has protruding parts. Namely, the recessed
parts of the first feeding tray 210 and the protruding parts of the
second feeding tray 310 mesh, and vice versa for the protruding
parts of the first feeding tray 210 and the recessed parts of the
second feeding tray 310.
[0039] The first feeding tray 210 is movable vertically (to the
directions coming in and out of the page in FIG. 3) against the
base 160, and movable perpendicularly away from the base 160 (to
the direction the arrow is pointing at in FIG. 3). The second
feeding tray 310, on the other hand, is movable only vertically
against the base 160.
[0040] The moving away of the first feeding tray 210 from the base
160 is conducted in order to get out of the way of the vertical
moving range of the second feeding tray 310. Once the first feeding
tray 210 is moved perpendicularly from the vertical direction, the
first feeding tray 210 can descend and then move back to a position
below the second feeding tray 310.
[0041] As the first feeding tray 210 and the second feeding tray
310 configure a meshing structure, when there is no sheet placed on
the first feeding tray 210, the empty first feeding tray 210 can
take over the second batch of sheets 220 on the second feeding tray
310 from below. Once the first feeding tray 210 becomes flush with
the second feeding tray 310, the first feeding tray 210, instead of
the second feeding tray 310, supports the second batch of sheets
220 and then continues to ascend to support the second batch of
sheets 220. This will be described later as a takeover
operation.
[0042] Next, a block diagram schematically showing the paper sheet
feeding apparatus according to the embodiment will be described in
detail. FIG. 4 is a block diagram schematically showing the paper
sheet feeding apparatus according to the embodiment.
[0043] As shown in FIG. 4, the outputs of the status sensor 140,
the first proximity sensor 170, the second proximity sensor 270,
the first sheet sensor 290, the second sheet sensor 390, the limit
sensor 180, and a start button 110 are input to a controller 100.
The start button 110 is a button pressed when placing the second
batch of sheets 220 onto the second feeding tray 310 to start the
later described additional supply operation.
[0044] The air blow unit 130, a first drive motor 211 for driving
the first feeding tray 210, an actuator 212 for moving the first
feeding tray 210, and a second drive motor 311 for driving the
second feeding tray 310 are connected to the controller 100. The
controller 100 drives the air blow unit 130, the first drive motor
211, the actuator 212, and the second drive motor 311, based on the
above-mentioned inputs.
[0045] Next, the basic operations of the paper sheet feeding
apparatus according to the embodiment will be described in detail.
FIG. 5 to FIG. 8 are schematic front views for explaining an
additional supply operation according to the embodiment. FIG. 9 to
FIG. 11 are schematic front views for explaining a takeover
operation according to the embodiment.
[0046] FIG. 5 shows a state where the pickup unit 150 is picking up
sheets from the first batch of sheets 120 on the first feeding tray
210. While the paper sheet feeding apparatus is at this state, an
operator places the second batch of sheets 220 on the second
feeding tray 310 so that the second batch of sheets 220 can be
picked up next. Once the operator places the second batch of sheets
220, he or she presses the start button 110. When the start button
110 is pressed, the controller 100 issues an instruction to elevate
the second feeding tray 310. The second feeding tray 310 then
ascends until the top surface of the second batch of sheets 220 is
detected by the first proximity sensor 170.
[0047] When the proximity of the second batch of sheets 220 is
detected, the second feeding tray 310 synchronizes with the
ascending speed of the first feeding tray 210 (as shown in FIG. 6).
The two feeding trays continue to ascend until the later described
upper limit sparseness value P1 is detected by the status sensor
140. Then, the first feeding tray 210 moves away (away from the
base, towards the direction coming out of the pages in FIG. 5
through FIG. 11). At the same time, the second feeding tray 310 is
removed of the synchronization with the first feeding tray 210, and
continues to ascend independently. In the meantime, the first batch
of sheets 120 on the first feeding tray 210 falls on to the second
batch of sheets 220 on the second feeding tray 310 (as shown in
FIG. 7).
[0048] Due to this fall, the second feeding tray 310 then supports
both the second batch of sheets 220 and the first batch of sheets
120 that had just been transferred. FIG. 8 shows a state where the
pickup unit 150 is picking up sheets one by one from the now
integrated batch of sheets. While the paper sheet feeding apparatus
is at this state, the first feeding tray 210 descends vertically
from the moved away position until it reaches a height lower than
the second feeding tray 310. Then, the first feeding tray 210 moves
back to its original vertical moving range and positions below the
second feeding tray 310 (as shown in FIG. 8).
[0049] Then, the first feeding tray 210 starts to ascend in order
to take over feeding by the second feeding tray 310 (as shown in
FIG. 9). The first feeding tray 210 ascends until the second
proximity sensor 270 detects that the first feeding tray 210 and
the second feeding tray 310 have become flush (as shown in FIG.
10). The second feeding tray 310 then descends, and with this, the
integrated batch of sheets is transferred to the first feeding tray
210 (as shown in FIG. 11). The second feeding tray 310 descends to
the lowest position, and the operator supplies the next batch of
sheets onto the second feeding tray 310 to prepare for the next
cycle of feeding.
[0050] As described above, while the first batch of sheets 120 is
being picked up by the pickup unit 150 from the first feeding tray
210, the next batch of sheets to be fed are supplied onto the
second feeding tray 310, and then the first batch of sheets 120 fed
by the first feeding tray 210 would be transferred to the second
feeding tray 310. This series of actions is hereinafter called the
additional supply operation.
[0051] Also, while the integrated first batch of sheets 120 and
second batch of sheets 220 are being picked up by the pickup unit
150 from the second feeding tray 310, the integrated batch of
sheets fed by the second feeding tray 310 would be transferred to
the empty first feeding tray 210. This series of actions is
hereinafter called the takeover operation.
[0052] The paper sheet feeding apparatus according to the
embodiment successively feeds sheets to the pickup unit 150, by
repeating these operations.
[0053] Here, a relationship between the sparseness value of sheets
and the position of the feeding tray in charge of feeding according
to the embodiment will be described in detail. As an example, the
state where the first feeding tray 210 is feeding the first batch
of sheets 120 will be described. FIGS. 12A and 12B are schematic
front views for explaining the relationship between the sparseness
value of sheets and the position of the feeding tray according to
the embodiment.
[0054] As the first feeding tray 210 elevates and the first batch
of sheets 120 gets close to the pickup unit 150, the cluster of
sheets in the upper part of the first batch of sheets 120 loosens
by the air blow unit 130. In the meantime, the status sensor 140
detects the sparseness value of the cluster of sheets in the upper
part of the first batch of sheets 120.
[0055] Of the sparseness values detected by the status sensor 140,
the sparseness value which indicates the densest state possible in
which sheets can be loosened by the air blow, is hereinafter called
the upper limit sparseness value P1. FIG. 12A shows the state in
which the status sensor 140 is detecting the upper limit sparseness
value P1. This state means that if the cluster of sheets has higher
denseness than it currently is, then the sheets would not be able
to be loosened properly and thus be liable to a picking up of two
or more sheets at once.
[0056] The sparseness value which indicates the sparsest state
possible in which sheets can be loosened by the air blow is
hereinafter called the lower limit sparseness value P2. FIG. 12B
shows the state in which the status sensor 140 is detecting the
lower limit sparseness value P2. This state means that if the
sheets have lower denseness than it currently is, then the sheets
would not be able to be sucked properly by the pickup unit 150 and
thus be liable to a malfunction of the picking up of sheets.
[0057] The distance between the position of the top surface of the
first feeding tray 210 when the upper limit sparseness value P1 is
detected and the position of the top surface of the first feeding
tray 210 when the lower limit sparseness value P2 is detected is
hereinafter called distance d. Distance d is a distance
corresponding to the range from the lower limit sparseness value P2
to the upper limit sparseness value P1. In other words, if the
first feeding tray 210 elevates by distance d from the position
where the detected sparseness value is the lower limit sparseness
value P2, indicating that the upper part of the first batch of
sheets 120 is at its lowest denseness possible, the upper part of
the first batch of sheets 120 then turns into its highest denseness
possible, detecting the upper limit sparseness value P1.
[0058] As the first feeding tray 210 elevates, the distance between
the first feeding tray 210 and the pickup unit 150 narrows, and the
upper part of the first batch of sheets 120 gradually becomes
denser. When the sparseness value reaches the upper limit
sparseness value P1, the controller 100 stops the first feeding
tray 210. Then, while the first feeding tray 210 is staying where
it is, the pickup unit 150 continues picking up sheets and thus the
upper part of the first batch of sheets 120 gradually becomes
sparser. When the sparseness value reaches the lower limit
sparseness value P2, the controller 100 elevates the first feeding
tray 210 again.
[0059] The things written here in the above paragraphs apply for
the second feeding tray 310 as well.
[0060] As described, the feeding tray that is in charge of feeding
would be controlled so that the sparseness of the upper part of the
batch of sheets would always stay within the range between the
upper limit sparseness value P1 and the lower limit sparseness
value P2. Namely, if the lower limit sparseness value P2 is
detected, the feeding tray would be elevated, and if the upper
limit sparseness value P1 is detected, the feeding tray would be
stopped from ascending. These are the basic operations
conducted.
[0061] Next, the relationship between the control of the sparseness
value and the positions of the feeding trays during the additional
supply operation according to the embodiment will be described in
detail, referring to FIG. 6 to FIG. 8.
[0062] First, as shown in FIG. 6, the distance from the uppermost
surface of the second batch of sheets 220 to the bottommost surface
of the first batch of sheets 120 when the top surface of second
batch of sheets 220 have neared the first proximity sensor 170 by a
certain distance, is hereinafter called distance DO. While the
movements of the first feeding tray 210 and the second feeding tray
310 are synchronized, the distance DO is maintained.
[0063] The time counting from when the first feeding tray 210 is
moved perpendicularly from the vertical direction until when the
first batch of sheets 120 and the second batch of sheets 220
integrate, is hereinafter called the integrating time. This is the
time it takes to change from the state shown in FIG. 7 to the state
shown in FIG. 8. The integrating time can be calculated from the
falling speed of the first batch of sheets 120 and the ascending
speed of the second feeding tray 310.
[0064] The second feeding tray 310 ascends by a distance of
distance D1 during the integrating time. The thickness of the total
amount of sheets that would be picked up by the pickup unit 150
within the period from when the first feeding tray 210 and the
second feeding tray 310 synchronize at distance DO until when the
first batch of sheets 120 and the second batch of sheets 220
integrate, is hereinafter called distance D2.
[0065] Here, the distance that the uppermost surface of the first
batch of sheets 120 descends during the moving away of the first
feeding tray 210, is hereinafter called margin D. As shown in FIG.
8, this margin D satisfies the following equation: D=D0+D2-D1.
[0066] If margin D is less than distance d, which corresponds to
the range of the suitable sparseness value of the sheets, the
sheets can be maintained to be properly picked up, while the first
feeding tray 210 moves away and the feeding is taken over by the
second feeding tray 310. Thus, the feeding of the sheets would not
be interrupted during the additional supply operation.
[0067] While the first feeding tray 210 moves away and the second
feeding tray 310 takes over the feeding, the sparseness of the
cluster of sheets in the upper part of the first batch of sheets
120 are controlled to stay within the suitable range by satisfying
the following equation: D<d.
[0068] Note that distance DO is a distance determined by the
thicknesses of the first feeding tray 210 and the first proximity
sensor 170. Distance D1 is determined by the speed of the first
feeding tray 210 moving away and the ascending speed of the second
feeding tray 310. Distance D2 is determined by the speed of the
first feeding tray 210 moving away, the ascending speed of the
second feeding tray 310, and the picking up speed of the pickup
unit 150.
[0069] Next, the whole operation of the paper sheet feeding
apparatus according to the embodiment will be described in detail.
FIG. 13 is a flowchart showing the whole operation of the paper
sheet feeding apparatus according to the embodiment.
[0070] The operator first places the first batch of sheets 120 on
the first feeding tray 210 so that they can be fed to the pickup
unit 150 (Step 1). This preparation is hereinafter called the
initial setup operation. Then, the first feeding tray 210 feeds
sheets from the first batch of sheets 120 while maintaining the
sparseness within the suitable range (Step 2). This operation is
hereinafter called the feed operation.
[0071] Then, as the sheets are fed and the amount of the first
batch of sheets 120 decreases, the operator supplies additional
sheets by placing the second batch of sheets 220 on the second
feeding tray 310 (Step 3). This operation is hereinafter called the
additional supply operation. After this operation is conducted, the
feeding tray in charge of feeding the sheets is switched from the
first feeding tray 210 to the second feeding tray 310. Then, in the
same manner as Step 2, the second feeding tray 310 feeds sheets
from the integrated first batch of sheets 120 and second batch of
sheets 220 while maintaining the sparseness within the suitable
range (Step 4).
[0072] Next, the empty first feeding tray 210 ascends until it
becomes flush with the second feeding tray 310. By doing so, the
first feeding tray 210 takes charge of supporting the stacked
sheets remaining on the second feeding tray 310 (Step 5). This
operation is hereinafter called the takeover operation. Then, the
state of the paper sheet feeding apparatus is back to that of Step
2, and from here onward, the operations Step 2 Step 5 are
repeated.
[0073] Note that the placement of the batch of sheets by the
operator can also be done by other automated machines.
[0074] Next, the initial operation (Step 1) shown in FIG. 13 will
be described in detail. FIG. 14 is a flowchart showing the initial
setup operation of the paper sheet feeding apparatus according to
the embodiment.
[0075] First, the controller 100 elevates the first feeding tray
210 when the first batch of sheets 120 is placed on it (Step 101).
Then, when the sparseness value detected by the status sensor 140
reaches an initial sparseness value P0 (Step 102), the controller
100 stops the first feeding tray 210 (Step 103). Then, the
controller 100 enables the air blow unit 130 and loosens the
cluster of sheets by blowing air towards the upper part of the
first batch of sheets 120 from the side of the upper part of the
first batch of sheets 120 (Step 104). The controller 100 also
enables the pickup unit 150 and makes it pick up sheets one by one
from the uppermost sheet on the first batch of sheets 120 (Step
105). Note that the detected sparseness value P0 is a value that is
set so that the sparseness of the upper part of the first batch of
sheets 120 reaches the upper limit sparseness value P1 when the air
blow starts to loosen the sheets.
[0076] Next, the feed operation (Step 2) shown in FIG. 13 will be
described in detail. FIG. 15 is a flowchart showing the feed
operation of the paper sheet feeding apparatus according to the
embodiment.
[0077] Once the picking up starts at Step 105 in FIG. 14, the
status sensor 140 detects whether or not the detected sparseness
value has reached the lower limit sparseness value P2 (Step 201).
While the detected sparseness value has not reached the lower limit
sparseness value P2 (`No` in Step 201), the controller 100 lets the
picking up continue without having the first feeding tray 210
elevated. Once the detected sparseness value reaches the lower
limit sparseness value P2 (`Yes` in Step 201), the controller 100
elevates the first feeding tray 210 (Step 202).
[0078] Once the first feeding tray 210 starts ascending, the limit
sensor 180 detects whether or not the first feeding tray 210 has
reached the elevation limit (Step 203). While the first feeding
tray 210 has not reached the elevation limit (`No` in Step 203),
the status sensor 140 detects whether or not the detected
sparseness value reaches the upper limit sparseness value P1 (Step
204). Once the detected sparseness value reaches the upper limit
sparseness value P1 (`Yes` in Step 204), the controller 100 stops
the first feeding tray 210 (Step 205). Then, the state goes back to
Step 201, and the operations (Step 201.about.) are repeated.
[0079] On the other hand, if the first feeding tray 210 has reached
the elevation limit (`Yes` in Step 203), the controller 100 stops
the ascending of the first feeding tray 210 (Step 206). The first
feeding tray 210 reaching the elevation limit means that there are
no more sheets additionally supplied and thus it is time to have
all the remaining sheets on first feeding tray 210 to be picked
up.
[0080] Then, the picking up continues until it is detected by the
first sheet sensor 290 that there are no more sheets left on the
first feeding tray 210 (Step 207). Once there are no more sheets
left on the first feeding tray 210 (Step 207), the pickup unit 150
ends its operation (Step 208).
[0081] According to these steps, the picking up continues
successively during the feed operation, having the sparseness value
maintained within the range of the upper limit sparseness value P1
and the lower limit sparseness value P2.
[0082] Next, the additional supply operation (Step 3) shown in FIG.
13 will be described in detail. FIG. 16 is a flowchart showing the
additional supply operation of the paper sheet feeding apparatus
according to the embodiment.
[0083] The controller 100 elevates the second feeding tray 310 when
the second batch of sheets 220 is placed on the second feeding tray
310 by the operator and the start button 110 is pressed (Step 301).
Then the second feeding tray 310 ascends until the first proximity
sensor 170, installed on the underside of the first feeding tray
210, detects the approach of the second feeding tray 310 (Step
302). Once the second feeding tray 310 approaches the first
proximity sensor 170 by a certain distance (`Yes` in Step 302), the
controller 100 synchronizes the ascending speed of the first
feeding tray 210 and the second feeding tray 310 (Step 303).
[0084] When the detected sparseness value reaches the upper limit
sparseness value P1 while the first feeding tray 210 and the second
feeding tray 310 are ascending (`Yes` in Step 304), the controller
100 stops the first feeding tray 210 and the second feeding tray
310 simultaneously (Step 305).
[0085] Then, the controller 100 moves away the first feeding tray
210 from its vertical moving range (to the direction of the arrow
shown in FIG. 3), and then makes it position below the second
feeding tray 310 (Step 306). As a result, the feeding tray in
charge of feeding switches from the first feeding tray 210 to the
second feeding tray 310 (Step 307). Until the integrating time
passes (Step 308), the controller 100 elevates the second feeding
tray 310 (Step 309).
[0086] After the integrating time passes, namely, when the first
batch of sheets 120 and the second batch of sheets 220 have
integrated (Step 308), the controller 100 stops the second feeding
tray 310 from ascending (Step 310). Then, the procedure continues
on to the supply operation (Step 4), described in FIG. 13.
[0087] The details of the supply operation (Step 4) described in
FIG. 13 are the same as the supply operation (Step 2) described in
FIG. 15; aside from replacing all first feeding trays 210 into
second feeding trays 310, so the details will be omitted.
[0088] Lastly, the takeover operation (Step 4) shown in FIG. 13
will be described in detail. FIG. 17 is a flowchart showing the
takeover operation of the paper sheet feeding apparatus according
to the embodiment.
[0089] The controller 100 elevates the empty first feeding tray 210
while feeding the sheets from the second batch of sheets 220 on the
second feeding tray 310 (Step 501). Once the second proximity
sensor 270 detects that the first feeding tray 210 has become flush
with the second feeding tray 310 (`Yes` in Step 502), the
controller 100 stops the first feeding tray 210 and descends the
second feeding tray 310 (Step 503). As a result, the feeding tray
in charge of feeding switches from the second feeding tray 310 to
the first feeding tray 210 (Step 504). Then again, the procedure
continues on to the feed operation (Step 2) described in the FIG.
13.
[0090] These were the detailed explanations of the paper sheet
feeding apparatus according to the embodiment shown in FIG. 13,
using FIG. 14 to FIG. 17.
[0091] By controlling the position of the feeding tray as
described, the sparseness of the sheets are maintained within the
suitable range at all times, including the feeding of the sheets,
the additional supplying of the sheets, and the taking over of the
feeding tray. Due to this, a successive feeding of the sheets by
the paper sheet feeding apparatus is realized.
[0092] Note that the `sheets` according to the embodiment include
media made of paper or resin, e.g., banknotes, stocks, postal
matters, magnetic cards, and the like.
[0093] While certain embodiments have been described, these
embodiments have been presented by way of example only, and are not
intended to limit the scope of the inventions. Indeed, the novel
embodiments described herein may be embodied in a variety of other
forms; furthermore, various omissions, substitutions and changes in
the form of the embodiments described herein may be made without
departing from the spirit of the inventions. The accompanying
claims and their equivalents are intended to cover such forms or
modifications as would fall within the scope and spirit of the
inventions.
* * * * *