DOCUMENT FEEDING METHOD AND APPARATUS
FIELD OF THE INVENTION
The present invention relates generally to the fielά υf άυcument hanάling systems anά, more particularly, to a paper currency feeάing methoά anά apparatus for use with a paper currency hanάling system. BACKGROUND OF THE INVENTION
A variety of techniques anά apparatuses have been useά to satisfy the requirements of automateά currency hanάling systems. As businesses anά banks grow, these businesses are experiencing a greater volume of paper currency. Consequently, these businesses are continually requiring that their currency be processeά in a more timely anά efficient manner.
One drawback of currency hanάling machines that process stacks of currency bills is the unreliability associated with striping individual bills from a stack of bills and feeding the stripped bills inte the currency processing machine. Specifically, often multiple bills are stripped anά feed into the machine at the same time. This situation often translates into the reprocessing of an entire stack of bills so that an accurate count of the bills can be made. Reprocessing stacks of bills adds to the overall time required t process a batch of currency. Accordingly, there is a need for a feeding mechanism which can more reliably strip bills from a stack of bills anά advance the stripped bills into a currency handling machine. SUMMARY OF THE INVENTION
A document feeding apparatus for use with a document processing άevice. The document feeding apparatus comprises an input receptacle adapteά to receive a stack of άocuments and at least one feeding wheel adapted to strip documents, one at a time, from the stack of documents. The feeάing wheel includes a moveable insert having a high friction surface adapteά to engage anά to aάvance each of the άocuments.
The above summary of the present invention is not intenάeά to represent each emboάiment, υr every aspect, of the present invention. Aάάitional features and benefits υf the present inventiυn will become apparent from the detailed description, figures, and claims set forth below.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the invention will become apparent upon reading the follυwing detaileά άescription in conjunction with the drawings in which:
FIG. 1 is a perspective view of a currency processing machine for use with the present invention;
FIG. 2 is a functional block diagram of the currency processing machine of FIG. 1;
FIG. 3 is an enlarged vertical section taken approximately through the center of a currency processing machine, but showing various transport rolls in side elevation, according to the prior art;
FIG. 4 is an enlarged perspective view of various transport rolls of a transport mechanism for use with a currency processing machine according to the prior art;
FIG. 5 is a cross-sectional view of variυus transport rolls of a transpυrt mechanism for use with a currency processing machine accorάing to the prior art; FIG. 6a is a cross-sectional view of various transport rolls υf a bill separating mechanism and transport mechanism for use with a currency processing machine according to one embodiment of the present invention;
FIG. 6b is a perspective view of a pair of feeding wheels according to one embodiment of the present invention; FIG. 7a anά 7b are siάe sectional views of a feeάing wheel accorάing to one embodiment of the present invention;
FIGS. 8a-d and 9a-d are siάe sectional views of a feeάing wheel shown in various pυsitions during the bill feeding process according to one embodiment of the present invention; FIG. 10 is an enlarged perspective view cf various transport rolls of a transport mechanism for use with a currency processing machine according to one embodiment of the present invention;
FIGS. 11 and 12 are a perspective views of a main drive roller according to one embodiment of the present invention; and FIG. 13 is a cross-sectional view of the main drive roller depicted in FIG. 11 alcng line 13 according to one embodiment of the present invention.
DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS
Referring now to FIGS. 1 and 2, there is shown a currency processing machine 10. The machine 10 includes an input receptacle 12 where stacks of currency bills that need to be identified and ccunted are pυsitioned. Bills in the input receptacle 12 are picked out or separateά, one bill at a time, anά sequentially relayeά by a bill transport mechanism 16, between a pair of scanheaάs 18a and 18b where, for example, the currency denomination of the bill is scanned and identified. In the embodiment depicted, each scanhead 18a,b is an optical scanhead that scans for characteristic information from a scanned bill 17 which is useά to identify the denomination of the bill. The scanned bill 17 is then transporteά to an output receptacle 20, which may incluάe a pair of stacking wheels 21, where bills so processed are stackeά for subsequent removal. In alternative emboάiments of the present invention, the machine 10 may incluάe a plurality of υutput receptacles such as άescribeά in commυnly υwneά U.S. Patent Nυ. 6,311,819. Fυr example, the present inventien may be employeά in a machine having two, four, or six output receptacles. The machine 10 incluάes a user interface 23 with a display 36 for communicating with a user of the machine 10. hi alternative embodiments of the present invention, additional sensors can replace or be used in conjunction with the optical scanheaάs 18a,b in the currency processing machine 10 to analyze, authenticate, άenominate, count, and/or otherwise process currency bills. For example, size detection sensors, magnetic sensors, thread sensors, and/or ultraviolet/fluorescent light sensors may be useά in the currency processing machine 10 to evaluate currency bills. The use of these types of sensers for currency evaluation are described in commonly owned U.S. Patent 6,278,795 592 incorporated herein by reference in its entirety.
According to one embodiment of the currency processing machine 10, each optical scanhead 18a,b comprises a pair of light sources 22 άirecting light onto the bill transport path so as to illuminate a substantially rectangular light strip 24 upon a currency bill 17 positioneά on the transport path aάjacent the scanhead 18. Light reflected off the illuminated strip 24 is sensed by a photoάetector 26 positiυned between the twυ light sυurces. The analog output of the photodetector 26 is converted
into a άigital signal by means of an analog-t -digital (ADC) converter unit 28 whose output is fed as a άigital input to a processor such as central processing unit (CPU) 30.
According to one emboάiment, the bill transport path is άefineά in such a way that the transport mechanism 16 moves currency bills with the narrow dimension of the bills being parallel to the transport path and the scan άirection. As a bill 17 traverses the scanheads 18a,b, the light strip 24 effectively scans the bill across the narrow dimensien υf the bill. In the embediment depicteά, the transport path is so arrangeά that a currency bill 17 is scanneά across a central section of the bill along its narrow dimension, as shown in FIG. 2. Each scanhead functions to detect light reflected from the bill as it moves across the illuminated light strip 24 and to provide an analog representation of the variatiυn in reflecteά light, which, in turn, represents the variation in the άark anά light content of the printeά pattern or indicia on the surface of the bill. This variation in light reflected from the narrow dimension scanning of the bills serves as a measure for distinguishing, with a high degree of confidence, among a plurality of currency άenominations which the system is programmed to handle.
Adάitional details of such a scanning apparatus and process are describeά in U.S. Patent Nos. 5,295,196 anά 5,815,592 each of which are incorporateά herein by reference in their entirety. While the currency process machine 10 has been άescribeά as a machine capable of determining the denomination of processed bill, the present invention is also applicable to note counting devices. Note counting devices are discloseά in commonly owned U.S. Patents Nos. 6,026,175, 6,012,565 and 6,311,819 592 each of which are incorporated herein by reference in their entirety. Further, the present invention is applicable to devices which feeά currency bill as well as other άecuments such as, for example, checks, stock certificates, postage stapes, and casino script.
Referring now to FIGS. 3-5, a prior art bill separating mechanism for use with the currency processing machine 10 will be άescribeά. The bills stacked on a bottom wall 205 of the input receptacle 12 are stripped, one at a time, from the bottom of the stack. The bills are advanced by a pair of feeding wheels 220 mounteά on a drive shaft 221. The feeding wheels 220 project through a pair of apertures or slots fonneά in the bottom wall 205. Part of the periphery of each wheel 220 is prcviάeά with a
raised high-fricticn, serrated surface 222 which engages the bottom bill of the input stack as the wheels 220 rotate, to initiate feeding movement of the bυttυm bill from the stack. The serrated surfaces 222 project radially beyonά the rest of the wheel 220 peripheries so that the wheels "jog" the bill stack άuring each revolutiυn sυ as to agitate anά loosen the bottom currency bill within the stack, thereby facilitating the feeding of the bottom bill from the stack.
The feeding wheels 220 feed each bill B (FIG. 4) onto a άrive roll 223 mυunteά en a άriven shaft 224 supperteά across the siάe walls of the machine 10. As can be seen mcst clearly in FIGS. 4 and 5, the drive roll 223 incluάes a central smooth friction surface 225 formeά of a material such as rubber or harά plastic. This smooth friction surface 225 is sandwiched between a pair of grooved surfaces 226 and 227 having serrated portions 228 and 229 formeά from a high-friction material.
The serrateά surfaces 228, 229 engage each bill after it is feά onto the άrive roll 223 by the feeάing wheels 220, te frictionally advance a bill into the narrow acute passageway formed by the curved guideway 211 aάjacent the rear siάe of the άrive roll
223. The rotational movement of the drive roll 223 and the feeάing wheels 220 is synchronized so that the serrated surfaces on the άrive roll 223 and the feeding wheels 220 maintain a constant relationship to each other. Moreover, the drive roll 223 is άimensioned so that the circumference of the outermost portiυns υf the grooved surfaces is greater than the width W of a bill, so that the bills advanceά by the άrive roll 223 are spaceά apart from each other. That is, each bill feά to the άrive roll 223 is aάvanceά by that roll only when the serrateά surfaces 228, 229 come into engagement with the bill, so that the circumference of the άrive roll 223 determines the spacing between the leading edges of successive bills. hi order to ensure firm engagement between the drive roll 223 anά the currency bill being feά, an iάler roll 230 urges each incoming bill against the smooth central surface 225 of the drive roll 223. The idler roll 230 is journalled on a pair of arms 231 which are pivotally mounted on a support shaft 232. Also mounted on the shaft 232, on oppυsite sides of the iάler roll 230, are a pair of grυυved retard rollers 233 and 234. The groυves in these two retard rollers 233, 234 are registered with the central ribs in the two groυved surfaces 226, 227 υf the άrive rυll 223. The retarά rollers 233, 234 are lecked to the shaft 232, which in turn is locked against movement
in the direction of the bill movement (clockwise as viewed in FIG. 3) by a one-way roller clutch 235. Each time a bill is fed into the nip between the retard rollers 233,
234 and the drive roll 223, the clutch 235 is energizeά to turn the shaft 232 just a few άegrees in a direction opposite the direction of bill mυvement. These repeateά incremental movements άistribute the wear uniformly arounά the circumferences of the retarά rollers 233, 234. The surface of each of the retard rollers 233, 234 has a coefficient of friction greater than that of a currency bill, but less than that of the inserts 228, 229 of the drive roll 223, for stripping the upper bill(s) from the bottom bill which is in contact with the drive roll 223 when multiple bills are advanced by the feeάing wheels 220. Although the idler roll 230 and the guide wheels 233, 234 are mounted behind the guideway 211, the guideway is apertureά to allow the roll 230 anά the wheels 233, 234 to engage the bills on the front siάe υf the guideway.
Beneath the idler roll 230, a spring-loaded pressure roll 236 (FIGS. 3 and 5) presses the bills into firm engagement with the smoυth fricticn surface 225 of the άrive roll as the bills curve άownwarάly along the guiάeway 211. This pressure roll
236 is journalleά on a pair υf arms 237 pivυteά en a statiυnary shaft 238. A spring 239 attacheά tc the lewer enάs υf the arms 237 urges the roll 236 against the άrive roll 233, through an aperture in the curved guideway 211.
At the lower end of the curved guiάeway 211, the bill being transported by the drive roll 223 engages a flat guide plate 240 (FIG. 3) which carries a lower scan head
18b (FIG. 2). Currency bills are positively driven along the flat plate 240 by means of a transport roll arrangement which includes the drive roll 223 at one enά of the plate anά a smaller driven roll 241 at the other end of the plate. Both the άriver roll 223 anά the smaller roll 241 include pairs of smooth raised cylindrical surfaces (not shown) which hold the bill flat against the plate 240. A pair of O rings 244, 245 (FIGS. 3 anά
4) fit into grooves formeά in both the roll 241 anά the roll 223 to engage the bill continuously between the two rolls 223 anά 241 to transport the bill while helping to hold the bill flat against the guide plate 240.
The flat guide plate 240 is provided with openings through which the raised surfaces of both the drive roll 223 and the smaller άriven roll 241 are subjecteά to counter-rotating contact with corresponάing pairs υf passive transport rolls 250 and 251 having high-friction rubber surfaces. The passive rolls 250, 251 are mounted on
the underside of the flat plate 240 in such a manner as to be freewheeling about their axes and biased into ccunter-rotating ccntact with the corresponάing upper rolls 223 and 241. The passive rolls 250 and 251 are biased into ccntact with the driven rolls
223 and 241 by means of a pair of H-shaped leaf springs (not shown). Each of the four rolls 250, 251 is cradled between a pair of parallel arms of one of the H-shaped leaf springs. The central portiυn υf each leaf spring is fastened to the plate 240, which is fastened rigiάly to the machine frame, so that the relatively stiff arms of the H- shaped springs exert a constant biasing pressure against the rolls and push them against the upper rolls 223 and 241. As bills are moved along the flat guide 240 plate, the bills are moveά past sensers which scan the bills or otherwise sample or evaluate. Bills are then moveά along the flat guiάe plate 240 to the stacker wheels 21 anά are stacked in the output receptacle 20. Further details of the mechanical and operational aspects, including the scanning techniques, of various embodiments of a currency scanning and counting machine 10 are describeά in άetail in commonly owneά U.S. Patent Ne. 5,815,592 entitled "Methed Anά Apparatus For Discriminating And Counting Dυcument" which is incorporated herein by reference in its entirety.
The present invention is directed towards a currency bill feeάing mechanism which has been founά to pro iάe more reliable bill feeάing results than that of the prior art. It has been founά that prior art feeding mechanisms often unreliably feed bills in certain situations. "Unreliable feeάing" refers to situations where multiple bills are feά, no bills are fed, or the bill feeding is not smooth.
The feeding of multiple bills sometimes occurs when larger stacks of bills are processed. The weight from a larger stack of bills increases the άegree of friction between the bottom bill anά the feeding wheels as well as the friction between adjacent bills near the bottom of the larger stack. When protruding inserts (e.g., inserts that extenά beyonά the periphery the feeάing wheels), are brought into contact with a large stack of bills to advance the bottom bill, the increased άegree of friction between adjacent bills at the bottom of the stack may result in the advancement of multiple bills. Without inserts that protrude beyond the periphery of the feeding wheels, however, it has been found that bills at the bottom of very small stacks of bill may not be properly advanced into the transport mechanism 16 because there is
insufficient weight forcing the bottom bill in the small stack downward into engagement with the feeding wheel when the small stack is joggeά by the protruding inserts.
The aforementiυned problems are mitigateά by providing a radially floating insert which extends beyonά the periphery υf each wheel a variable άistance D. Very generally, the radially flcating inserts enable the pair of feeding wheels to operate as theugh the feeding wheels each include a protruding insert when the stack of bills is small and operate as though the feeάing wheels each incluάe an insert which is less protruάing or "non-protruάing" when the stack of bills is large. When the stack of bills is large the raάially floating insert is helά within the feeάing wheel to reάuce the occurrences of advancing multiple bills and when the stack of bills is small the radially floating insert is moved radially outward to engage the bottom bill in a stack of bill and to advance that bottom bill.
Referring now to FIG. 6a and 6b, various transport rolls of a bill separating mechanism 300 anά transport mechanism for use with a άocument or currency processing is shewn. Bills stackeά on the bottom wall 205 of the input receptacle 12 are aάvanced, one at a time, from the bottom of the stack. The bottom bill of the stack of bills is advanced by a pair of feeάing wheels 302, mounteά on a άrive shaft 221. The feeding wheels 302 project through a pair of slits or apertures 304 formed in the bottom wall 205. While the separating mechanism 300 includes two feeάing wheels
302 mounted on a commυn drive shaft 221, a single feeding wheel 302 will be discussed in order to simplify the follυwing descripticn υf the operation ef the feeding wheels 302. Each feeding wheel 302 is proviάeά with a raάially floating insert 308. The insert 308 sliάes along a post 310 άisposed in a generally inverted "T" shapeά aperture υr slot 312 άisposeά within the feeάing wheel 302. The post 310 extenάs raάially outward within the slet 312 tυwards the υuter periphery 306 ef the wheels 302. In alternative embediments υf the feeding wheel 302, the raάially fleating insert is sliάeably engageά to a slυt in the wheel anά net a pυst. Like the insert 222 discussed in connection with FIGS. 3-5, the raάially floating insert 306 incluάes a high-friction, serrated surface which engages the bottom bill of a stack of bills placed in the input receptacle 12 as the feeάing wheel 302 rotates, to initiate feeάing movement ef the bettom bill from the stack. Each rotation of the feeάing wheel 302
brings the insert 308 into contact with the bottom of the stack of bills to aάvance the bottom bill. In one emboάiment, each feeάing wheel 302 has a άiameter of approximately 1.5 inches (about 3.81 cm).
Referring now to FIGS. 7a anά 7b, a feeάing wheel 302 having a raάially floating insert 308 is shown. In FIG. 7a, the radially floating insert 306 is shown in a
"minimally extendeά" position such that the insert extenάs beyonά the periphery of the feeάing wheel 302 a minimum άistance D In alternative embodiments, the distance D\ ranges between approximately zero inches (about zero cm) and approximately 0.050 inch (about 0.127 cm), hi one embodiment of the present invention, the distance Oι is about zero inches (about zero cm). The radially floating insert 302 is able to freely slide along a post 310 disposeά with the slot 312 between the "minimally extenάed" position (FIG. 7a) and a fully extendeά position shown (FIG. 7b). In the fully extended position, the insert 308 extends a maximum άistance D2 beyonά the periphery of the feeding wheel 302. In alternative embodiments, the distance D2 ranges between approximately 0.020 inch (about 0.051 cm) and approximately 0.200 inch (about 0.508 cm). In one embodiment of the present invention, the distance D2 is approximately 0.040 inch (about 0.102 cm). Further extension of the radially floating insert beyonά the maximum distance D2 is limited by flanges 314 of the insert 308 which engage walls 316 of the slot 312. hi other alternative emboάiments, the inset άees net include flanges and the slot does not include walls 316 to limit further extension of the insert 308. Rather, in such embodiments, further extension of the radially floating insert 308 beyonά the maximum distance D2 is limited by a resilient member such as a spring, a small chain or cable, a wire, or a string. In an alternative emboάiment of the present invention, the raάially floating insert is biaseά towarάs the extended position by resilient member such as a spring.
As the feeding wheel 302 rotates, the rotatiυnal mυvement of the wheel 302 forces the insert 308 to slide raάially outwarά along the post 310 into the extenάeά position. As wheel 302 rotates, the insert 308 comes into contact with the bottom of a stack of bills. When the insert contacts a stack of bills, the weight of the bills may force the insert 308 raάially inwarά. The extent to which the insert is forceά raάially inwarά άepenάs upon the size/weight of the stack of bills as well as the rotatiυnal
speed of the wheel 302. When the stack of bills is large, the weight of the stack of bills forces the insert to its "minimally extenάeά" position as the insert contacts the stack of bills. When the stack of bills is small (anά light), the weight ef the stack of bills is insufficient to mυve the insert te its "minimally extenάeά" position allowing the insert 308 to maintain its extension beyond the periphery 306 of the feeding wheel
302. Depending on the size/weight ef the remaining stack of bills, the insert 308 may be forced radially inward by the stack of bills such that the insert 308 extends beyond the periphery 306 of the wheel 302 a distance less than D2 but greater than D
Each rotation of the feeάing wheels 302 separates υne bill from the stack of bills. Accorάingly, when the currency hanάling machine 10 is processing bills at a rate of about 800 bills per minute, the feeάing wheels 302 have a rotational speeά of about 800 revolutions per minute. (In alternative emboάiments, the machine 10 is capable of processing from about 800 to over 1500 bills per minute.) Accorάing to one emboάiment of the present invention, each of the inserts 308 are maάe out of a urethane material and have a weight of approximately 0.20 (approximately 0.056
Newton). Each of the feeding wheels have a άiameter of approximately 1.5 in (approximately 3.81 cm). The feeάing wheels are made out of hard plastic such as Delrin®.
Referring now to FIGS. 8a-d anά 9a-ά, the operation of a feeάing wheel 302 with raάially floating inserts 308 will be άescribeά. As the feeάing wheel 302 rotates
(counterclockwise as viewed in FIGS. 8a-d anά 9a-ά), bills are aάvanced, one at a time, toward a main feeding/drive roll 320 of the machine 10. In FIG. 8a-d, a large stack of bills 320 are stackeά upon the bottom wall 205. The rotational movement of the feeάing wheel 302 creates a centrifugal force that forces the insert 308 to move raάially outwarά such that the insert extends beyond the periphery 306 of the feeding wheel 302 (e.g., towards the fully extended position) as shown in FIG. 8a. As feeding wheel rotates, the insert 308 is brought into contact with the bottom bill 322 of the large stack of bills 320 as shown in FIG. 8b. As the wheel continues tc rotate the insert 308 engages the bettυm bill 322 and begins to advance the bill forward (to the left as viewed in FIGS. 8a-d). The weight of the large stack of bills 320 pushes the insert 308 radial inward back within the wheel 302 until the bottom of the insert 308 presses against the bottom υf the slυt as shυwn in FIG. 8c (e.g., the "minimally
extended" position). The insert 308 rotates past the stack of bills 320 having advanced the bottom bill 322. Because the weight of the large stack of bills 322 is no longer acting on the insert 308, the insert 308 is free to slide radially outward as shown in FIG. 8d back into the fully extended position. This movement of the insert 308 is repeated for each revolution of the wheel 302 until the stack of bills is reduced in size wherein the weight of the smaller stack of bills is toυ small tυ press hυld the insert back within the slot 312 of the wheel 302 towarά its minimally extenάeά position.
In FIG. 9a, a small stack of bills 324 is shown resting upen the bettom wall 205. The rotational movement of the feeάing wheel 302 forces the insert 308 to move raάially outwarά such that the insert extends beyond the periphery 306 of the feeding wheel 302 (e.g., to the fully extendeά positiυn) as shυwn in FIG. 9a. As the feeding wheel 302 rotates, the insert 308 is brought into ccntact with a bottom bill 326 of the stack of bills as shown in FIG. 9b. As the wheel continues to rotate the insert 308, still in the fully extendeά positiυn, it "jυgs" the stack υf bills 324 anά engages the bettom bill 326 and begins te advance the bottom bill 326 forwarά (to the left as viewed in FIGS. 9a-d). When the insert contacts the stack of bills, the stack of bills is forced upward resulting in more driving force on the bottom bill. This loosens the bottom bill. The weight of the small stack of bills 324 is insufficient to force the insert 308 radially inward back within the wheel 302 when the stack of bill is small.
Therefore, in the example shown in FIGS. 9a-ά, the insert 308 maintains its fully extended position throughout the revolution of the wheel 302. As the wheel 302 continues to rotate, the bottom bill 326 is pushed forward by the extenάeά insert 308 as shown in FIG. 9c until the insert is rotateά below the bottom wall 205. Referring now to FIGS. 10-13, the feeάing wheels 302 aάvance each strippeά bill B into engagement with a main drive roller 330. Accorάing to the emboάiment of FIGS. 10-12, an integrated main drive roll arrangement 330 is shown. According to one embodiment, the main drive roll arrangement 330 is fabricated from a single piece of material and ccmprises a άrive shaft 332 anά a wheel portion 350. The wheel portion includes outer roller portions 352, O-ring grooves 354 to accommodate O- rings such as O-rings 244, 245 (FIG. 4), walls 356 , and two pairs of shallow grooves 340 and 342 formeά in the surface of the drive roller 330 which correspond to grooved
retard rollers 233, 234. A space 356 disposed between walls 356 hold a rubber ringed called a "tire" 260 that, along with the pressure roller 236, engage bills advanced by the bill separating mechanism 300. The pressure roller 236 presses each of the bills into firm engagement with the tire 260 disposed in the space 356 between walls 356. The outer roller portions 352 of the main άrive roller 330 contact the iάle rollers 250 to positively άrive bills along the flat plate 240 (FIG. 3).
In one emboάiment, the integrateά drive roll 330 is machined out of a single piece of aluminum. Forming the άrive roller 330 of υut a single piece of material alleviates alignment issues associateά with attaching components such as rollers 223 to the άrive shaft 224 of FIG. 4. In order to process 800 bills per minute, the main drive roller 330 rotates on the orάer of approximately 800 revolutions per minute, (hi alternative emboάiments, the machine 10 is capable of processing from about 800 to over 1500 bills per minute.) Because the main drive roller 330 rotates at such high speeds, a high άegree of precision is requireά άuring the alignment of the components associated with the dive roller. Integrating the rollers 223 and the άrive shaft 332 eliminates the step of aligning these two components άuring the manufacturing process which in turn reάuces the maintenance requirements of the machine 10.
The άrive roller 330 illustrated in FIG. 10-13 operates in a manner similar to the prier art arrangement in illustrated in FIG. 4. Bills B aάvanceά to the άrive roller 330 by the feeding wheels 302 are held against the central portions 334 of the main drive roller 330 by the idle roller 230. As the main άrive roller 330 rotates (clockwise as vieweά in FIG. 10), each bill is aάvanceά into the nip formed by the drive roller 330 and the grooved retard rollers 233 and 234. In situations where multiple bills are advanced by the feeάing wheels, the grooveά retard rollers 233, 234 strip the upper bill(s) from the bottom bill which is in contact with the main drive roller 330.
The groυves in the retard rollers 233, 234 are registereά with the two pairs of grooves 340, 342 fermeά in the main άrive roller 330. The twe pairs of grooves 340- 342 extenά arounά the periphery of the main άrive roller 330 (e.g., circumferential grooves). The grooves 340, 342 are shallow such that the surface of the άrive roller 330 is substantially smooth. In the embodiment of the drive roller 330 illustrated in
FIG. 10, the groυves 340, 342 have a depth of approximately 0.010 inch (about 0.025 cm) anά a wiάth of approximately 0.150 inch (about 0.381 cm). The άrive roller in the
depicted embodiment has a diameter of approximately 1.5 inches (about 3.81 cm).
Reducing the depth of the grooves 340, 342 has been founά to facilitate the bill feeding process. Unreliable feeding can be causeά by the tendency for limp currency bills to be forced into conformity with deeper grooves which can cause bills to become jammed while stiff currency bills may not have full contact with the bottom of deeper grooves which can cause bill slippage resulting in the piling-up of bills. Either of these situations can result in multiple bills being fed or insufficient distance between bills, each of which can cause feeding errors.
The main άrive roller 330 incluάes a pair of inserts 344 anά 346 made of out a high friction material such as rubber. The inserts 344, 346 differ for those of the prior art arrangement illustrated in FIG. 4 in that the inserts 228, 228 υf the present inventien are substantially smυυth (e.g., nυt serrateά), but άe contain circumferential grooves that corresponά to the grooves 340, 342 άisposeά in the main άrive roller 330 and mate with the retard rollers 233, 234. The inserts 344, 346 engage each bill after is it feά into engagement with the main άrive rollers by the feeάing wheels 302, to frictionally aάvance each bill into the narrow acute passageway formed by the cured guideway 211 adjacent the rear side of the drive main άrive roller 330. Set screws (not shown) are useά to mount the inserts 344, 346 to the main άrive roller 330.
Tυ further guarά against the simultaneeus remυval of multiple bills from the stack in the input receptacle 12, particularly when small stacks of bills are loaάeά into the machine 10, the feeάing wheels 302 are always stoppeά with the raάially floating inserts 308 positioneά below the bottom wall 205 of the input receptacle 12. This is accomplished by continuously monitoring the angular position of the radially flυating inserts 308 of the feeding wheels 220 via the encoάer 32, anά then controlling the stopping time of the άrive motυr sυ that the metυr always stυps the feeding wheels
302 in a position where the radially floating inserts 308 are located beneath the bottom wall 205 of the input receptacle 12. Thus, each time a new stack of bills is loaάeά into the machine 10, those bills will rest on the smooth portions of the feeάing wheels 302. This has been founά to aiά in the reάuction of simultaneously feeάing of άouble er triple bills, particularly when small stacks υf bills are invelveά.
While the inventien is susceptible tc variυus mυάifications and alternative forms, specific embodiments thereof have been shown byway of example in the
άrawings anά herein άescribeά in detail. It should be understood, however, that it is not intended to limit the invention to the particular forms discloseά, but on the contrary, the intention is to cover all moάifications, equivalents, anά alternatives falling within the spirit and scope of the invention as defineά by the appended claims.