WO2002082385A1 - A detector arrangement for use in conjunction with document transporting means - Google Patents

Abstract

Detectors (33, 34, 43, 44) are mounted on a common positionally adjustable carrier (50) mounted at the input to a document transporter (1) so that the carrier (50), mounted adjacent the input to the transporter (1), will position two laterally separated detectors (33, 34) in the input nip (13) of the transporter, and position two further detectors (43, 44) downstream of the first detectors (33, 34), said further detectors being separated transversely to the direction in which the document is transported. The detectors are coupled to a computer (80) which functions to evaluate the documents with respect to their movement and orientation.

Description

A detector arrangement for use in conjunction with document transporting means

The present invention relates to a detector arrangement intended for use in conjunction with document transporting means.

By document we mean a document of value such as a banknote, cheque or the like, typically a rectangular sheet. For the sake of simplicity, the invention will be described in the following with reference to banknotes.

When banknotes are dispensed from a banknote cassette for instance, and advanced to and into a banknote transporter (belt transporter or an equivalent device, for further conveyance, one banknote at a time) , it is normally necessary to gather information concerning the banknotes in several respects.

Several separate sensor units are used in a conventional transport system to this end; these sensor units being - an outfeed sensor that detects whether or not a banknote has actually been dispensed from the cassette and received by the transporter,

- a typical mechanical thickness measuring device which functions to ascertain whether or not a banknote received by the transporter is a double outfeed, in other words consists of two or more mutually overlaying or overlapping banknotes,

- a banknote speed sensor,

- a banknote length sensor. The work involved in mounting these sensor units is relatively extensive and the units are normally dispersed over a relatively long distance along the banknote transporter. Moreover, these sensor units shall be connected to monitoring means, for instance to a computer, for evaluation of the information obtained from the sensor units, or detectors, it being necessary to provide the computer or monitor with information relating to the relative distances between the detectors whose signals are to be processed.

In accordance with the present invention, an arrangement for sensing documents which are fed singly into a document transporter that includes a pair of shaft- parallel, mutually co-acting rotatably driven rolls that define therebetween an infeed nip that leads to a document transport path, wherein the arrangement includes optical detectors disposed along said path, is characterised in that the detectors are mounted on a common carrier mounted at the location of the transporter infeed and positionally adjustable such that the carrier will have at the transporter infeed a first optical detector arrangement that includes two mutually separated detectors which lie along a line that extends perpendicular to the direction of document transportation and parallel with the nip, and a second detector arrangement that includes two detectors which are mutually separated transversely to the direction of document transportation and are located downstream of the first detector arrangement in said transportation direction; and in that the detectors are adapted for connection to a computer which on the basis of signals received from the detectors, said signals indicating that an edge of a document has passed respective detectors, evaluates said documents with respect to their motion and orientation.

The present invention provides a detector arrangement which can be mounted adjacent the transporter in a simple fashion and with relatively small effort, and which has a relatively small construction length along said transporter, and where the detectors/sensors are located in pre-known and determined positions so that a computer used for said evaluation work can be provided beforehand with corresponding information on which evaluation of received signals can be based, wherewith the computers may be provided beforehand with limit values, or threshold values, with which the detector signals or the values calculated on the basis of these signals can be compared, such as criteria for initiating attendant activities (for instance that a banknote shall be deflected from the transportation path when the banknote is askew, crooked, damaged, or a doubled outfeed, etc.).

The invention also enables a detector arrangement to be provided which allows the acceleration of a banknote in the input region of the transporter to be readily ascertained; the acceleration of a banknote constitutes valuable information with respect to the control of a banknote separating device in the banknote cassette arrangement for instance, regarding dispensing single banknotes .

In one particularly preferred embodiment of the invention, the detectors are mounted on a detector carrier along two mutually parallel lines. The carrier includes conventional means for simple and adjustable mounting of the carrier in the input region and adjacent the transporter input nip, in a manner such that the first line will lie in the transporter input nip and extend at right angles to the banknote transporting direction and lie adjacent the plane of the banknotes. The second line lies downstream of the first line and is spaced therefrom at a distance within which the banknote will have been accelerated to the speed of the transporter.

With respect to a longitudinal centre line of the transporter, along which the longitudinal centre of the banknotes runs, there is provided along each detector line two detectors which are preferably spaced equidistantly from said longitudinal centre line. The detectors, however, are spaced at different distances from the longitudinal centre line of the transporter along both of said lines. The detectors are preferably optical detectors and may each have the form of a light source that is directed transversely to the plane of the banknote and towards a light sensor, the output signal of which may thus determine the presence/absence of a banknote in the beam path, and can suitably sense the transparency of the banknote. The detector is thereby also able to detect whether or not a single banknote lies in the beam path or whether or not several banknotes are present simultaneously in the beam path.

In an alternative embodiment, the detector may include a light source and a detector in the proximity of one another and on the same side of the banknote transport plane, such that the detector will detect light deriving from the light source and reflected by the banknote. The reflected light may have different characteristics also in this case, said characteristics determining whether the light has been reflected by a single banknote or by a so- called double outfeed. The provision of at least two detectors along a detector line provides redundancy in respect of the arrangement. The arrangement will function effectively, even if one of the detectors malfunctions. Because the detectors are located in relative positions that are determined and known beforehand, adjustment of the carrier will mean that all detectors have known positions in relation to the transporter input nip and the longitudinal centre of the transporter, so as to enable the computer to be programmed correspondingly, partly for evaluating magnitudes that can be calculated on the basis of the detector signals and also so that the computers can also be programmed with respect to evaluating limits for initiating attendant measures.

The invention will now be described in more detail with reference to exemplifying embodiments thereof and also with reference to the accompanying drawings, in which:-

Figure 1 is a schematic sectioned view of an inventive arrangement, taken on the line I-I in Figure 2;

Figure 2 is a schematic view taken on the line II-II in Figure 1; and,

Figure 3 is a schematic view taken on the line III-III in Figure 2. It will be seen that the invention includes a banknote transporter 1, for instance a belt transporter, which has two shaft-parallel rolls 12 at its input end 11. The rolls 12 mutually co-act to define a nip axis 13 on which a banknote 5 fed from the nip is gripped by the transporter. The leading edge 6 of the banknote 5 will normally be parallel with the nip line or axis 13. Respective endless belts 14 extend around the nip-defining rolls 12 and said rollers may be driven to drive the belts 14 in the indicated directions at a chosen, conveniently constant, speed. The speed of the transporter 1 is usually much higher than the speed at which the banknote 5 is fed into the transporter, and the banknote 5 will therefore be accelerated in the input part of the transporter 1. The rate of acceleration can vary, depending on retardation of the banknote 5 in a banknote dispensing means 99 affiliated, for instance, with a cassette from which banknotes 5 are dispensed one at a time. Retardation of the banknotes in the cassette dispensing means serves, most often, to separate double outfeed of banknotes initially dispensed from the cassette. Information relating to banknote acceleration in the transporter input section can thus be used to control retardation of banknotes in the banknote dispensing means in the cassette, with the aim of minimising banknote wear and reducing the frequency at which doubled banknotes are fed into the transporter 1. The rolls 12 include a central shaft 121 on which a series of coaxial bundle-carrying and separated rollers 122 are mounted. As will be seen in particular from Figures 1 and 2, a number of detectors 33, 34, 43, 44 is mounted on a carrier 50. In the illustrated case, the carrier 50 comprises two mutually connected and mutually parallel detector-carrying discs, or plates, 51, 52. Each detector may include a light source 61 and a light sensor 62 mounted on a respective disc 51, 52 and arranged in alignment with one another so as to detect the presence of a banknote in the beam path passing therebetween. The discs 51, 52 have tongues 53, 54 which project forwards in the space between mutually adjacent rollers 122. The end portion of respective tongues extends above and beneath the nip axis and the detectors 33, 34 in alignment with the nip axis 13.

The detectors 33, 34, 43, 44 are coupled to a computer 80.

The carrier 50 has a transporter-accommodating cut-out or recess, which enables the transporter 1 plane and the space between the carrier discs 51, 52 to receive banknotes 5 for passage along the transporter 1. The carrier 5 has a known fitting 57 which facilitates mounting of the carrier 50 adjacent the transporter 1, in a position and in an orientation chosen in the following way: The carrier 50 includes a first rectilinear line or row 35 of detectors 33, 34, wherein the carrier 50 is mounted so that said line 35 coincides with the engagement nip between the rolls 12 and is thus parallel with two edges 6, 7 of a banknote 5 that has been fed correctly into the transporter 1. The carrier 50 also includes two detectors 43, 44 that are disposed along a line or row 45 which extends parallel with the line 45 and which is spaced therefrom at a distance c.

The transporter has a longitudinal centre line 21 which is situated midway of the banknote edges 6 and 7, when the banknotes have been fed correctly into the transporter. The detectors 33, 34 are situated equidistantly from the line 21, at spacings al, a2 and on respective sides of said lines. The detectors 43, 44 are disposed equidistantly from the line 21, at spacings bl, b2 and on respective sides of said lines.

The distances al, a2 are suitably identical. The distances bl, b2 are also suitably identical and preferably differ form the distance al/a2. A banknote 5 passing through the transporter 1 will therefore be sensed along four essentially parallel tracks. The time difference between signals from detectors 34 to 44 and the signals from detectors 33 to 43, this latter concerning the trailing edge 7 of a banknote 5, may be used to calculate the speed of the banknote 5 in the transporter 1. The length d of the banknotes 5 can be determined on the basis of the known speed of the transporter 1, said length normally being correlated to the denomination of the banknote .

This length information can be utilised to deflect a detected or sensed banknote to an appropriate end station.

Because the distance c between the lines 35, 45 is known, a time difference in the signals sent, for instance, from the detector 34 and the detector 44 with respect to the leading edge 6 of a banknote for instance, constitutes a measurement of banknote acceleration, wherewith this information can be used to control parts of a banknote transporting system, for instance the banknote separator in the cassette dispenser arrangement.

Any crookedness in the attitude of a banknote 5 can be determined by measuring the time difference between the signal sensed by the detectors 43, 44 in a line 54, particularly when the speed at which the banknote is transported is known.

By designing the detector sensors 62 to distinguish between the outfeed of single banknotes and double-feed banknotes, the information obtained can be utilised to deflect any banknotes that are folded double or that overlap, etc. If the detectors 35, 45 and 34, 44 on respective sides of said longitudinal centre line 21 give substantially different values, this deviation can be utilised to detect torn or double-folded parts of a banknote, so that such a banknote can be deflected away from the banknote transporting path. The inventive arrangement also provides the person skilled in this art with other evaluation options.

The invention affords the fundamental advantages of knowing the relative positions of the detectors 33, 34, 43, 44 and enabling the detectors to be disposed in two lines or rows at a relatively small distance apart in the vicinity of a transporter input nip, by simple fitting the carrier 50 adjacent the transporter 1, wherewith a monitoring and controlling computer to which the detectors are connected can be pre-programmed with respect to the detection of "erroneous" banknotes, so as to cause such banknotes to be deflected from the transport path on the basis of such detection. The ends of the carrier have the form of a rectangular tubular element and are received in guide slots in the side plates supporting the transporter 1. The carrier 50 can be displaced along the slots 58, to enable the detectors 33, 34 to be brought into alignment with the nip 13 between the nip-defining rollers 122 of the transporter. Although not shown, the arrangement includes locking elements which enable the carrier to be locked in a set position.

Claims

1. An arrangement for sensing documents (5) which are fed singly into a document transporter (1) that includes a pair of shaft-parallel, mutually co-acting rotatably driven rolls (12) that define therebetween an infeed nip that leads to a document transport path, wherein the arrangement includes optical detectors (33,34,43,44) disposed along said path (1) , characterised in that the detectors (33,34,43,44) are mounted on a common carrier (50) mounted at the location of the transporter infeed and positionally adjustable such that the carrier (50) will have at the transporter infeed a first optical detector arrangement (33, 34) that includes two mutually separated detectors (33, 34) which lie along a line (35) that extends perpendicular to the direction of document transportation and parallel with the nip (13) , and a second detector arrangement that includes two detectors (43, 44) which are mutually separated transversely to the direction of document transportation and are located downstream of the first detector arrangement in said transportation direction; and in that the detectors (33,34,43,44) are adapted for connection to a computer (80) which on the basis of signals received from the detectors, said signals indicating that an edge of a document has passed respective detectors, evaluates said documents with respect to their motion and orientation.

2. An arrangement according to Claim 1, characterised in that the computer (80) functions to initiate deflection of documents from the transporter on the basis of a comparison made between document detection signals and a control value .

3. An arrangement according to Claim 1 or 2 , characterised in that the detectors (43, 44) of the second detector arrangement are disposed along a line (45) that extends parallel with the line (35) of the first detector arrangement .

4. An arrangement according to any one of Claims 1 to 3, characterised in that the detectors (33, 34) of the first detector arrangement are disposed at pre-determined, preferably equal, distances (al, a2) from the longitudinal centre line (21) of the transport path.

5. An arrangement according to any one of Claims 1 to 4 , characterised in that the detectors (43, 44) of the second detector arrangement are disposed at pre-determined and preferably equal distances (bl, b2) from the longitudinal centre line (21) of the transport path (1) .

6. An arrangement according to Claim 4 or Claim 5, characterised in that the distance from the longitudinal centre line (21) of the transporter to said detectors is different in the first and second detector arrangements.