Patent Application
20160090249
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.
Embodiments described herein relate generally to a paper sheet feeding apparatus.
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.
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.
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.
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.
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.
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.
Hereinafter, a paper sheet feeding apparatus of an embodiment will be described with reference to the drawings.
First, the setup of the paper sheet feeding apparatus of the embodiment will be described in detail.
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.
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.
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
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
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.
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.
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.
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.
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.
Here, a meshing structure of the feeding trays according to the embodiment will be described in detail.
The first feeding tray 210 and the second feeding tray 310 configure a meshing structure. As shown in
The first feeding tray 210 is movable vertically (to the directions coming in and out of the page in
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.
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.
Next, a block diagram schematically showing the paper sheet feeding apparatus according to the embodiment will be described in detail.
As shown in
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.
Next, the basic operations of the paper sheet feeding apparatus according to the embodiment will be described in detail.
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
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.
Then, the first feeding tray 210 starts to ascend in order to take over feeding by the second feeding tray 310 (as shown in
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.
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.
The paper sheet feeding apparatus according to the embodiment successively feeds sheets to the pickup unit 150, by repeating these operations.
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.
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.
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.
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.
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.
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.
The things written here in the above paragraphs apply for the second feeding tray 310 as well.
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.
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
First, as shown in
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
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.
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
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.
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.
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.
Next, the whole operation of the paper sheet feeding apparatus according to the embodiment will be described in detail.
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.
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).
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.
Note that the placement of the batch of sheets by the operator can also be done by other automated machines.
Next, the initial operation (Step 1) shown in
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.
Next, the feed operation (Step 2) shown in
Once the picking up starts at Step 105 in
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˜) are repeated.
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.
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).
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.
Next, the additional supply operation (Step 3) shown in
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).
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).
Then, the controller 100 moves away the first feeding tray 210 from its vertical moving range (to the direction of the arrow shown in
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
The details of the supply operation (Step 4) described in
Lastly, the takeover operation (Step 4) shown in
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
These were the detailed explanations of the paper sheet feeding apparatus according to the embodiment shown in
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.
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.
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.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2014-202634 | Sep 2014 | JP | national |
