GB2096808A - Magnetic card reading equipment - Google Patents

Abstract

In a magnetic card reader, the card drive system includes a drive wheel 9 which bears on the card and not only drives it along a guideway 12 which extends perpendicular to the drive wheel axis but also, being of frusto-conical shape, applies to the card a lateral thrust which (for both directions of travel of the card) keeps it against that side of the guideway (including a bearing surface) towards which the wheel diameter increases. In combination with such drive wheel a novel magnetic-head configuration 8 against which the card is pressed by the drive wheel is well adapted for use with cards in which the magnetic material is of high coercivity and is embedded within the thickness of the card and not exposed at the faces thereof. Photo-electric sensors enable opening of an entry shutter, starting of the motor, and other transport operations. Two card drive units and readers with multiple track reading heads are also disclosed. An erase head may remove data from cards having low coercivity magnetic material. <IMAGE>

Description

SPECIFICATION Magnetic card reading equipment This invention relates to magnetic card reading equipment and to card transport means incorporated in such equipment.

According to one aspect of the present invention a card transport means of magnetic card reading equipment comprises a guideway for the passage of such a card, a bearing surface forming one side of the guideway and defining the transport path of such card, and a drive wheel arranged to bear upon such card and, when rotatably driven, to drive the card along the said transport path, the drive wheel having its rotational axis in the plane perpendicular to the direction of transport of the card along the transport path where the drive wheels bears upon the card and being arranged to impose a lateral bias on the card whereby the card is thrust against the said bearing surface as well as being driven along the said transport path.

Preferably the rotational axis of the drive wheel extends, in the said perpendicular plane, parallel to the plane of the transport path where the drive wheel bears upon the card, and the drive wheel is of frusto-conical form, being of increasing radius towards that side of the guideway which is formed by the said bearing surface.

Particularly (but not only) in card transport means in which a single drive wheel as referred to above constitutes the only drive means and the only or at least the major lateral biassing means applied to a card within that region of the transport path which, for the card in question, is within range of the drive wheel, it is advantageous that a magnetic head positioned to support and be slidingly engaged by that part of the card upon which the drive wheel bears should present to such card a thrust-reaction surface of which the extent, lengthwise of the guideway and the transport path therethrough, is substantially greater than that of magnetic elements of the head exposed at that surface; and according to another aspect of the invention an improved configuration of magnetic head is provided which possesses the desired physical extent while achieving a desirable relationship between the boundaries of such exposed magnetic elements at the surface and a card sliding over such surface in contact therewith.

According to another aspect of the present invention a card transport means for use in an.

automated transaction comprises a guideway for the passageway of a card, the guideway extending through a slot which provides at least an exit for a card from the transport means, means for driving a card along the guideway, printing means controlled to print a record of a transaction, dispensing means adapted to supply record material from a roll thereof past said printing means and across the path of a card approaching the exit slot, the path of the record material being such that the record material is, in operation, folded over the leading edge of the card as the card enters said slot, the folded material being driven through the slot by the card, and means being provided for severing the folded material so that the card and the severed folded material can be withdrawn together from the slot.

Also according to the invention, the driving means of a card transport means of a card reading equipment preferably incorporates signal generating means providing an indication of the driving rate of said driving means, magnetic reading means of the equipment being controlled to sample card data at a rate determined by said signal generating means.

According to a preferred feature of the invention, magnetic card reading means comprises a magnetic reading head adjacent a guideway for the passage of magnetically encoded cards having magnetic coding portions of predetermined coercivity, and means for applying to any card passing through such guideway a bias field of predetermined level insufficient to saturate magnetic coding portions of said predetermined coercivity.

Embodiments of magnetic card reading equipment incorporating card transport means in accordance with the present invention will now be described, by way of example, with reference to the accompanying drawings, of which: Figure 1 is a perspective exploded view of equipment incorporating the invention, Figure 2 is a cross-sectional sketch of the card transport means according to the invention incorporated in the equipment shown in Figure 1, Figure 3 illustrates part of a guideway of the card transport means shown in Figure 2, Figure 4 is a more detailed plan view of a card transport and reading means according to the invention, Figure 5 is a sectional view taken on the line V-V of Figure 4, Figure 6 is a sectional view taken on the line VI--VI of Figure 4, and Figures 7 and 8 are respectively a plan and an elevation of a magnetic head shown in Figures 5 and 6.

Referring first to Figure 1 of the accompanying drawings, this shows the main constituents of magnetic card reading equipment embodying the invention, viz. card transport means 1, an electronic circuit board 2 (for processing card information), a power module 3, a receipt printer 4, and a shuttered slot 5.

Referring now to Figure 2, this illustrates the card transport means as incorporating a guideway 1 2 in an extrusion member 6 of uniform cross section, and which, in this case, is manufactured from an extrusion cut to length for the particular size of card to be read. A bearing member 7, consisting of a strip of material having a low coefficient of friction, is positioned on edge in a groove in the guideway 12 to form a side wall for the passage of the card 14. Each magnetic card 14 which is required to be read has a magnetic strip 13 whose longitudinal edge is parallel to and inset from a longitudinal edge of the magnetic card 14. The card 14 is inserted into the guideway 1 2 with the magnetic strip 1 3 facing downwards as shown.The card is biased, in its travel through the guideway 12, against the bearing member 7 so as to maintain constant the position of the magnetic strip 13 relative to the side of the extrusion member 6. Mounted underneath this extrusion member 6 is a magnetic reading head 8 which is arranged to read the information contained on the magnetic strip 1 3 of a passing card 14. The card 14 is driven through the guideway 12 by a wheel 9 driven in turn by a drive motor 1 0. The wheel 9 has a resilient urethane tyre 1 5 in frictional contact with the card 14. This wheel 9 as well as propelling the card 14 along the guideway 12 biases the card 14 against the bearing member 7.This biasing is achieved by a bevel on the resilient tyre 1 5 which is thus of frusto-conical form, so as to provide a flicking or whipping action by the greater diameter edge of the tyre 1 5. The resulting differential forces on the card across the tyre 1 5 produce a transverse bias force urging the card toward the bearing member 7. Obviously a wheel 9 made totally from a suitable resilient material could be made to serve the same purpose as the tyred wheel 9.

Referring now to Figure 3, this shows how a card 14 in the guideway 12 may be biased towards the bearing member 7 before and after the card 14 is acted upon by the tyred drive wheel 9. Biasing is provided by two springs 11 fixed to the guideway 12 so as to engage the edge of a card 14 opposite the bearing member 7. These springs 11 are located, one at the entrance and one at the exit of the guideway.

The operational sequence of the invention will now be described. Mounted at one end of the guideway 12 is a card entry slot 5 and a shutter control. Two photo-electric sensors (not shown in Figures 1 to 3) are located in the entry to the card slot 5 in such a position that only a card 1 4 of sufficient width interrupts both sensor beams. The slot 5 itself will reject cards of excessive width.

Sensing of the insertion of a card of the correct width causes the shutter to be lifted, allowing the card to be inserted fully into the guideway. The slot is shuttered to prevent access of undersize objects or access whilst another card is present in the equipment. When the card 14 is pushed in far enough a third photo-electric sensor is operated and the motor 10 is signalled to start. The drive wheel 9 rotates in such a direction as to draw the card 14 into the guideway 12 and across the magnetic head 8 while urging it against the bearing member 7 as previously explained. The card 14 emerging from the magnetic head 8 interrupts a fourth sensor which switches off the motor 1 0. Time-signals from the pre-encoded magnetic card 14 are meanwhile decoded by the electronic circuit board 2.The travel of the card 14 along the guideway 12 is biased by a combination of the springs 11 and bevelled drive wheel 9 as described above. The magnetic strip 13 of the card 14 is thus always accurately presented to the magnetic head 8. The bearing member 7 is incorporated in the extrusion member 6 in such a way as to be replaceable when worn as a result of continual card pressure. After the card 14 has interrupted the fourth sensor the card 1 4 may subsequently be passed back and forth within the mechanism for re-reading or writing of new data on to the card 14. Various operational options are then possible depending on the type of transport chosen.For example, the card can be passed forward between another drive wheel 9 and magnetic head 8 that may be set to decode signals from cards coded to an alternative or idertical card standard to that of the first drive/head assembly. Any number of such assemblies can be mechanically mounted end on for applications for fast card throughput of read/write/read-after-write nature. If desired, a facility may be provided such that subsequent to card reading, the card 1 4 can be driven under program control into a container under the extrusion member 6 and held permanently whilst freeing the transport 1 for use with other cards.

Such a facility allows bad debt cards to be collected automatically for subsequent destruction.

The mechanical design may incorporate, as indicated in Figure 1, an assernbly combined with the shuttered entry slot 5 such that whilst a card 1 4 is within the transport a paper receipt 1 6 can be issued up into the exit path of the card 14. The emerging card 14 will force the receipt 1 6 back through the same slot 5 as the card 14. The paper will be wrapped around the leading edge of the card 14 and be forced at an acute angle against a tear off edge mounted beneath the transport. The receipt 1 6 is then torn off accurately when the card 14 and receipt 1 6 are removed.The construction is such that both card 1 4 and receipt 1 6 must be removed together and designed such that remaining paper stock is securely held within the transport behind the shuttered slot 5 protected from weather conditions, should the transport be mounted for outside use.

The electronic circuit board 2 contains circuitry to interface to and control the aforementioned transport. The electronics are based upon use of a microcomputer and associated components such that the range of transport options is under program (software) control. The electronic circuit board 2 can amplify and decode signals from magnetic cards with inputs from up to 4 recorded tracks simultaneously. The various possible encoding standards are decoded by the microcomputer by sampling the incoming signals at a programmable rate'set to meet the requirements of the particular encoding method used. Manchester code, Bi Frequency and pulse width modulations are three current methods of encoding that can be used.

A fundamental requirement of reading and writing on magnetic cards using the above methods of encoding is that the number of bits per unit length (bit density) shall be constant during decoding/encoding. The electronic circuit board 2 has a motor-controlled system that takes digital pulses generated by a rotary pulse generator arrangement attached to the d.c. motor 10, and driven thereby at a speed proportional to that of the drive wheel 9 and a card 14 driven by it. Card decoding and encoding is servo locked to the speed of the pulse train received from the motor 10 ensuring reading and writing on the cards 14 is carried out at constant bit density regardless of the absolute speed of the card 14.

The electronics circuit board 2 can handle signals from magnetic cards 14 of low or high coercivity (magnetic strength) magnetic strips. As a means of providing added security when highcoercivity cards are used, circuitry is provided that will erase any low-coercivity copies of highcoercivity cards. This is implemented by feeding a bias current through the high-coercivity read head 8 from a precision current source. A d.c. field is thus set up across the read head 8 sufficient to saturate low-coercivity magnetic strips whilst not affecting the reading of high-coercivity cards.

Data read from a card 14 is stored on the electronics circuit board 2 and can be formatted under program control in many desired ways compatible with industry standard protocols for subsequent serial transmission to other equipment.

The further embodiment of a card transport and reading means in accordance with the invention illustrated in Figures 4 to 8 comprises a body or chassis 21 which may advantageously be constructed from constant-section metal extrusions cut to appropriate length and machined to produce windows, slots and other apertures as required for mounting and accommodating other components. In the illustrated instance, two card drive units are provided in tandem relationship, as described below, and the chassis length is determined accordingly. The chassis 21 provides a guideway 22, defining a transport path through the chassis for a magnetic card to be processed therein. Along one side, the guideway 22 is fitted with an elongate bearing member 23 which is preferably of low-friction material but also, preferably, is readily removable for replacement in the event of wear occurring.A magnetic card being transported through the guideway is biassed laterally against the bearing member 23, principally (as described below) by an active lateral bias applied by the drive means but also, in a subsidiary degree, by resilient bias members 24 mounted at the other side of the guideway 22 and positioned, spaced therealong, to project resiliently and displaceably into the path of that edge of a magnetic card which is remote from the bearing member 23.

At its front end, i.e. that end at which a magnetic card may be presented for insertion into it, the chassis is provided with a shuttered slot unit 25 which includes a solenoid 26 controlling a shutter 27 which normally closes a card entry slot 28 leading, when not so closed, to the guideway 22. The slot 28 itself is of such width as to prevent insertion of a card of greater than correct width.

Insertion of a card 29 of correct width (but not of one whose width is too small) is detected by both of a spaced-apart pair of infra-red detector units, each comprising a source 30 and an associated detector 31, and simultaneous detection by both detector units is made to result in energisation of the solenoid 26 to raise the shutter 27 and open the slot 28 for continued insertion of the card which enters the guideway 22 as indicated by chain lines 29'. Sliding engagement of one edge of the card 29 with a first of the bias members 24 ensure that as the card moves further into the guideway 22 its other edge slides along the bearing member 23 and the card is properly aligned with the transport direction.

By the time the card 29 has been fully inserted into the slot 28, its leading edge has passed and been detected by a further detector unit comprising an infra-red source 32 and associated detector 33, causing a drive motor 34 to be energised and rotate a drive wheel 35 and drive onward the card 29 which is by then engaged between the wheel 35 and a thrust-reaction member 36 over which the card slides while remaining frictionally engaged by the rotating wheel 35. The member 36 might be a magnetic head for data-transferring co-operation with the card 29, but is not so in the illustrated embodiment, in which it and the drive wheel 35 serve only to feed the card to and from a cardprocessing station which is not directly within reach of the entry slot 28.

The card-processing station comprises a drive motor 37 like the motor 34, a drive wheel 38 like the drive wheel 35, and a magnetic head 39, as well as two further infra-red detector units comprising, respectively, sources 40 and 41 and detectors 42 and 43. Detection of the arrival of the leading edge of the card 29 by the detector 40, 42 is made to initiate the card-reading process by means of the magnetic head 39 and also to cause the motor 37 to be energised (unless, as may be the case, the detector 32, 33 is arranged to cause energisation of both the motors 34 and 37 together.The detector 41, 43 detects that the trailing edge of the card 29 is about to leave the pinch between the drive wheel 38 and the magnetic head 39, and is arranged to cause the motors 34 and 37 to stop and then to drive the drive wheels 35 and 38 in reverse so as to feed the card back towards the entry slot 28.

If new data is to be written on to the card by means of the head 39, that may be done during the reverse pass of the card over the head, and the detector 40, 42 may be arranged to detect completion of this reverse pass and to reverse the motors once again so that the card makes a further forward pass over the head during which a checking read-after-write operation may be carried out. Alternatively, a read/write/read-afterwrite sequence may be carried out during three successive forward passes of the card, separated by two reverse passes and followed by another reverse transport of the card which finally causes it to protrude once again for manual removal from the entry slot 28.The behaviour of the drive motors 34 and 37 and the shutter 27 in response to signals from the various infra-red detectors is programmed under the control of circuitry on an electronic circuit board 44 (shown in Figure 4) which also controls the data-handling functions carried out by means of the magnetic head 39.

The motor 37 drives not only the drive wheel 38 but also a rotary pulse generator 45 which thus generates pulses at a frequency which is proportional to the speed of the drive wheel and of the card 29 driven thereby. The pulses from the generator 45 are also fed to the circuit board 44, and made to control the rate at which data reading or writing is effected, so that this rate is proportional to card transport speed, corresponding to a constant bit density on the card even though the absolute speed of transport of the card may not be accurately controlled.

At least the peripheries of the drive wheels 35 and 38 are of slightly resilient material (such as urethane) providing good frictional engagement with the card 29, and they are slightlyfrusto- conical (of increasing diameter towards the side of the guideway 22 at which the bearing surface 23 is provided) so that, as already described, rotation of either drive wheel provides not only movement of the card along the guideway 22 but also a lateral thrust which causes it to bear smoothly against the bearing surface 23 and be properly positioned with its magnetic strip properly positioned and aligned with respect to the magnetic head 39.This lateral thrust is produced even though the rotational axis of the drive wheel is not only in a plane which is perpendicular to the direction of transport of the card along the transport path as defined by the guideway 22 but is also, within that plane, parallel to the plane of the transport path; and, since the said perpendicular plane which includes the axis of rotation is perpendicular to the direction of transport, the lateral thrust is in the same direction for both directions of rotation of the drive wheel and thus for both forward and reverse feed of the cards which is thus held steadily against the bearing member 23.

The interposition of the drive wheel 35 and reaction member 36 between the entry slot and the magnetic head 39 serves to isolate the card while it is co-operating with the head; but if only a simple reading of the card is to be carried out, after which the card without, multiple reversals, is to be immediately returned to the entry slot for manual removal; such an intermediate drive-only station may be unnecessary and may be omitted, the card reading station then being relocated to the position at which the drive-only station is shown.

The provision of only a single drive wheel 38 to provide transport of the card 29 over the magnetic head 39 and to hold the card in close contact with the head as it slides thereover makes it desirable that the thrust-reaction surface presented to the card by the head should be of substantially greater extent, lengthwise of the transport path of the card, than the extent in that direction of the magnetic elements of the head as exposed at the thrust-reaction surface. This feature is provided by the head 39, which is shown on a larger scaie in Figures 7 and 8.

As shown in Figure 7, the head 39 is a threetrack head (though it might equally well have been designed for more tracks or less) and has three magnetic read/write units embedded in it.

Each such unit has a magnetic core carrying read and write coils (not shown) and having both its poles 45 and 46 exposed at a thrust-reaction surface 47 of the head over which the card 29 slides, driven by the wheel 38. The poles 45 and 46 of each read/write unit of the head are magnetically separated from one another at the surface 47 by the head magnetic gap 48 which extends right across the surface but is filled with non-magnetic material so that the surface is physically uninterrupted. In order to provide the desired extension of the surface 47 lengthwise of the transport path of the card, the head is formed with additional surfaces 49 and 50 which lie in the same plane at the surface 47 but are separated from it by grooves 51 and 52 respectively.It will be observed that the exposed ends of the poles 45 and 46 extend beyond the edges of the surface 47 and into the grooves 51 and 52 respectively. This means that their exposed transverse interfaces, 53 and 54, with the non-magnetic head material in which they are embedded are located down in the grooves 51 and 52 and are not contacted by a card passing over the head in contact with the surfaces 49, 47 and 50. This is believed to result in reduced wear of both heads and cards. It is believed that dust due to wear, including magnetic material, tends to be swept along by a moving card and then to be strongly retained at a transverse interface between magnetic and nonmagnetic material, particularly if the interface is not one of two interfaces at a gap, like the gap 48, between two closely adjacent magnetic elements.

Thus the interfaces 53 and 54 tend to collect such dust and, if they were in contact with the moving cards, the dust would have an abrasive effect and produce exaggerated wear. Such an unwanted effect is avoided by use of the design disclosed, while yet providing the desired extended physical support for the cards.

As already mentioned above, card reading and transport means according to the invention may be designed for use with cards whose magnetic strip incorporates high-coercivity magnetic material, and may in such case include means which will erase information coded on a card presented to it if the magnetic material of that card is low-coercivity material. For that purpose, the thrust-reaction member 36 shown in Figure 5 may be replaced by an erase head supplied with an erase signal at a level which will leave unaffected the high-coercivity cards which may properly be inserted but which will erase data from a fraudulent or other card which is not authorised, if it employs low-coercivity magnetic material.

Particularly in cards using high-coercivity strongly magnetised material, it is feasible to embed the magnetic strip (which may be of normal thickness) within the thickness of the card (as shown in Figure 2) rather than having it exposed at one face of the card. In such a card, of course, surface wear leaves the magnetic strip unaffected. One way of producing the sheet material for such a card is to overlay a layer of suitable plastic material with the magnetic strip in the normal way, with the strip exposed at one surface of the layer, and then (whilst the first layer is still plastic) to overlay both with a further layer of the same or another plastic which bonds to the first layer as both layers are allowed or caused to harden. The first layer may be thinner than normal, so that the combination of both layers gives a card of normal thickness, or the thickness of the two layers together may be reduced to that of a normal card, by rolling or pressing.

The above-described card transport means, with its single drive wheel at any given part of the card transport path, is rugged and simple in both construction and operation, and especially when combined with magnetic heads of the improved kind described, operating in conjunction with cards in which the magnetic strip of a highly magnetised high-coercivity material and is protected as above described from surface wear, there results a system which offers a desirable degree of simplicity and ruggedness in use.

Claims (10)

1. A card transport means of magnetic card reading equipment comprising a guideway for the passage of such a card, a bearing surface forming one side of the guideway and defining the transport path of such card, and a drive wheel arranged to bear upon such card and, when rotatably driven, to drive the card along the said transport path, the drive wheel having its rotational axis in the plane perpendicular to the direction of transport of the card along the transport path where the drive wheel bears upon the card and being arranged to impose a lateral bias on the card whereby the card is thrust against the said bearing surface as well as being driven along the said transport path.

2. A card transport means as claimed in Claim 1, wherein the rotational axis of the drive wheel extends, in the said perpendicular plane, parallel to the plane of the transport path where the drive wheel bears upon the card, and the drive wheel is of frusto-conical form, being of increasing radius towards that side of the guideway which is formed by the said bearing surface.

3. A card reading and transport means of magnetic card reading equipment comprising a magnetic head positioned to support and be slidingly engaged by a card pressed thereagainst and moved thereover by a rotatable wheel located adjacent the head, the head presenting to such card a thrust-reaction surface in which surfaces of magnetic elements of the head are exposed, wherein the extent of the thrust-reaction surface, lengthwise of the card transport path thereover, is substantially greater than that of the said exposed surfaces of the magnetic elements but the said thrust-reaction surface is crossed by grooves and the transverse extreme interfaces, with respect to the lengthwise direction of the transport path, between the said exposed surfaces of the magnetic elements and surrounding non-magnetic material of the head are disposed in the grooves and thus out of the plane of the thrust-reaction surface and out of contact with a card pressed thereagainst.

4. A card reading and transport means as claimed in Claim 3 and also as claimed in Claim 1 or Claim 2.

5. A card transport means for use in an automated transaction comprising a guideway for the passage of a card, a slot which provides at least an exit for a card from the guideway, means for driving a card along the guideway, printing means controlled to print a record of a transaction, dispensing means adapted to supply record material from a roll thereof past said printing means and across the path of a card approaching the exit slot, the path of the record material being such that the record material is, in operation, folded over the leading edge of the card as the card enters said slot, the folded material being driven through the slot by the card, and means being provided for severing the folded material so that the card and the severed folded material can be withdrawn together from the slot.

6. A card transport means as claimed in any of Claims 1 to 5 and incorporating signal generating means providing an indication of the driving rate of said driving wheel or means, magnetic card reading means associated therewith being controlled to sample card data at a rate determined by said signal generating means.

7. A card transport means as claimed in Claim 5 or 6 and also as claimed in any of Claims 1 to 4.

8. A card transport means as claimed in any of Claims 1 to 7 and incorporated in card reading equipment for use with cards having a magnetic strip incorporating magnetic material of high coercivity, wherein there is associated with the transport means an erase head energised at a level to leave such high-coercivity cards magnetically unaffected to but erase magnetically stored data of a card having a magnetic strip incorporating magnetic material of substantially lower coercivity.

9. A card transport means substantially as described herein with reference to any of the accompanying drawings.

10. A card having a longitudinal edge and, parallel thereto, a codable magnetic strip, wherein the magnetic strip contains magnetic material of high coercivity and is embedded within the thickness of the card and is not exposed at either face thereof.