GB1572052A

GB1572052A - Readers for use with magnetic strips and for generating control signals in response thereto

Info

Publication number: GB1572052A
Application number: GB1158477A
Authority: GB
Original assignee: SERVICE DISTRIBUTORS Inc
Current assignee: SERVICE DISTRIBUTORS Inc
Priority date: 1977-03-18
Filing date: 1977-03-18
Publication date: 1980-07-23

Description

(54) IMPROVEMENTS IN OR RELATING TO READERS FOR USE WITH MAGNETIC STRIPS AND FOR GENERATING CONTROL SIGNALS IN RESPONSE THERETO (71) We. SERVICE DISTRIBUTORS, INC., a Corporation organised and existing under the laws of the State of California, United States of America, of 567 Seventh Street, San Francisco, State of California. 94103, United States of America, do hereby declare the invention. for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to a reader for use with a magnetic strip and for generating a control signal in response thereto, and is generally applicable to a system employing such a reader in a laundry or vending machine, enabling cards bearing such magnetic strips to be used instead of coins for actuating the machine.

A serious problem in the business of providing laundry and vending machines is the fact that dishonest patrons sometimes open coin boxes which entails not only the loss of the coins but the expense of repair of the coin boxes. Thus. for a long time the need for a system to eliminate the use of coins in actuating machines of this type has existed. but the various substitutes for coins have not proven to be commercially satisfactorv.

According to the present invention there is provided a reader for use with a magnetic strip and for generating a control signal in response thereto, the strip bearing at least one magnetic signal indicative of the number of times the strip can be used in the reader to generate the control signal. the reader comprising transducer head means for selectively reading and erasing magnetic signals on such a magnetic strip being used in the reader, means for transporting the strip past the head means in a first direction on feeding the strip to the reader and then in a second direction to eject the strip from the reader, the head means being responsive to said magnetic signal or signals for providing a positive pulse corresponding to the or each magnetic signal on said strip passing the head means when said strip is transported past the head means in said first direction and a negative pulse corresponding to the or each magnetic signal on said strip passing the head means when said strip is transported passed the head means in said second direction, a counter, means for incrementing the counter in response to positive pulses from the head means and for decrementing the counter in response to negative pulses and means responsive to the counter for generating said control signal when the counter indicates that the strip being read can be used at least once more to generate the control signal, and for effecting erasing by said head means of at least one magnetic signal from the strip when the strip is transported in the second direction.

The strip can conveniently be provided on a card and, where the control signal is used for actuating a laundry or vending machine. the strip may be encoded for a given number of machine cycles. before the card is sold to patrons and used by patrons for one or more machine cvcles.

The reader apparatus is preferably made to fit into the coin box of an existing type of laundry machine and is dimensioned so that it occupies the space occupied by a conventional coin acceptor in a vending machine or laundry machine. No change in the wiring of the existing equipment is required in order to make the same compatible with the reader.

The cards and equipment are suitable for use under the conditions existing in coin operated laundries. For example. there is frequently a considerable amount of steam originating in the laundry equipment. as well as dampness on the floor. The equipment is not affected by such conditions: and even if the card is dropped on a damp floor, it is not adversely affected.

In one embodiment, the reader includes a casing having plates spaced apart in a longitudinally extending gap slightly greater than the thickness of said card and wide enough to receive said card, said casing having a front formed with a slot in registry with said gap and dimensioned to receive said card. a reversible motor in said casing. first and second shafts each resiliently mounted transversely and parallel to said plates. first and second rollers each fixed to one of said hafts and extending into said gap to grip and transport a card inserted into said slot through said gap, a first switch in said casing hiving first switch actuating means extending into said gap positioned to be actuated by the leading edge of a card inserted into said slot to actuate said first switch to energize said motor in a first direction. first drive means interconnecting said motor and said first shaft, second drive means driving said second shaft from said first shaft in a direction opposite said first shaft. a second switch having second switch actuating means extending into said gap a fixed distance inward of said first switch actuating means positioned to be actuated by the leading cdge of said card when it has been moved by said rollers into said gap a fixed distance to actuate said second switch to reverse said shafts. said transducer head means being located in the casing along the path of movement of said strip.

This construction can be simple and inexpensive using few moving parts or other parts requiring maintenance. The electronic components can be solid statc.

One of the advantages of the reader is the fact that it is unnecessary to modify either an encoder for encoding the cards or the reader when it is necessary to change the price charged for the service or article vended. Heretofore, when coin acceptors have been used.

each time a price change occurred a considerably amount of hardware was required to change the coin acceptors for the revised price: and, further, labour was required in installing new acceptors. These problems are eliminated using the present reader.

Conveniently, said transducer head means is a reader as claimed in any preceding claim wherein said transducer head means is arranged to provide said positive and negative pulses in response to sawtooth-shaped magnetic signals on the strip each having a slowly changing ramp portion and a rapidly changing step portion. said positive and negative pulses being produced in response only to said step portions either preceding or following said ramp portions in accordance with said directions of transporting the strip passed the head means.

Although in a preferred embodiment of the invention the card is transported into and out of the reader by a motor drive. nevertheless, by a modification which is set forth herein the card may be manually inserted and withdrawn. The sawtooth pulse has even more utility when the card is manually controlled.

Comveniently also. said incrementing and decrementing means is arranged to increment the connter in response to one less than the total number of positive pulses corresponding to magnetic signals On snid strip. Then. said counter responsive means may be arranged to generate said control signal in response to said counter being decremented to zero by hegative pulses. Thus. each card is encoded with one more pulse than the nominal number of pulses or "credits" for which the card is sold. In the reader, preferably the first pulse detected by the transducer head means is diverted or "skipped" so that it does not inerement the counter.Thus when the counter counts down to zero, there is still one pulse on the card and conveniently this pulse is erased as the control signal is generated. i.e. the laundry or vending machine is energized. Viewed from another standpoint. in the preferred embodiment. on the use of the card for the last credit. the first pulse does not energize the counter but is skipped as the card is inserted. The second pulse drives the counter up one count. On the withdrawal of the card. the first pulse drives the counter down to zero and the last pulse is then erased. Hence the onrd cannot be used subsequently to actuate the machine.

A specific embodiment of the present invention will now be described by way of example with reference to the accompanying drawings in which similar reference numerals represent corresponding parts in each of the several views.

In the drawings: Figure 1 is a top plan view of a typical card used in accordance with the present invention.

Figure 2 is an expolded perspective view showing a portion of the reader used to read the card.

Figure 3 is a perspective view showing the reader assembled and a card about to be inserted.

Figure 4 is a vertical sectiona vies. somewhat schematic, through the reader taken substantially along the line ±-+ of Figure 2.

Figure 5 is a horizontal sectional view taken substantially along the line 5-5 of Figure 4.

Figure 6 is a vertical sectional view taken substantially along the line 6-6 of Figure 5.

Figures 7 and 8 are fragmentary sectional views taken substantially along the lines 7-7 and 8-8 respectively of Figure 5.

Figure 9 is a perspective view of an encoder used in accordance with the invention.

Figure 1() is a horizontal sectional view taken substantially along the line 10-10 of ligure 9.

Figure 11 is a vertical sectional view taken substantially along the line 11-11 of Figure 10.

Figure 12 is a diagramatic representation of magnetic puises encoded onto the magnctic strip of the card with flux density plotted against distance along the strip. Figure 12A is a diagramatic representation of the signals generated in the reader when a card of the type shown in Figure 1 having pulses recorded on it as shown in Figure 12 is moving forward (inward) in the reader.

Figure 12B is a representation similar to Figure 12A showing the signal generated in the reader when the card is moving in the reverse direction.

Figure 13 is a block diagram of the card reader.

Figure 14 is a schematic diagram of the reader circuit.

Figure 15 is a block diagram of the encoder.

Figure 16 is a schematic diagram of the encoder circuit.

Coin box 21 shown in FFigures 2 and 3 is a rectangular metallic box of a type commonly used with coin acceptors in automatic laundry equipment. A pair of vertically spaced apart openings 22 is formed in the front panel 23 thereof. A feature of a preferred embodiment of the present invention is that it is adapted to fit into such a box 21 without modification, it being understood that other boxes may be substituted.

Fiuing into the box 21 is a reader 26 having a front panel 27 compatible with panel 23 and formed with a slot 28 for reception of a card 31. Also formed in panel 27 is display window 29 through which the patron may observe the number of "credits" (i.e. the number of times which a washing machine may be energized in accordane with the amount paid in the purchase of the card) at the beginning and at the completion of each use of the card.

Card 31 is subject to considerable modification. As shown. it is a thin rectangular member of cardboard or plastics material having rounded corners and bearing one or more longitudinally extending magnetic strips 32 which may be printed or otherwise affixed thereon. Preferubly. an arrow 34 is applied t indicate the direction of insertion of card 31 in slot 28. A plurality of magnetic pulses (indicated schematically by reference numeral 33 in Figure 1) is applied to strip 32. The original number of pulses 33 applied depends on the amount the patron is charged. Each time the card is used, one pulse 33 is removed.

Reader 26 comprises a top casing 36 horizontally disposed and having its forward end attached to panel 27 and a bottom casing 37 there-below and held parallel and spaced apart by one or more shims 38 so that a gap 39 exists between the casings 36 and 37 which is in registry with the slot 28 and is dimensioned to accommodate passage of a card 31. Serews 40 spaced along the longitudinal edges of casings 36 and 37 pass through holes in shims 38 and hold casings 36 and 37 assembled. The spacing between shims 38 is equal to the width of card 31. The forward edges of the shims 38 curve outwardly to facilitate insertion of cards into gap 39.

Top casing 36 has a base 41. Figure 5. upstanding sides 42 and is preferably closed with a cover 43. Mounted extending transversely by means of a clamp 45 fastened to base 41 is a miniature motor and reduction gear combination 46 which is preferably D.C. operated and reversible. Pinion 47 is mounted on the outer end of the final shaft of motor and reduction gear 40 and pinion 47 drive a train of gears 48 which are affixed to one of the sides 42 by means of a series of pins 49. The final gear 51 of the train of gears is rotatably mounted on the front end of top casing 36 and fits through a slot 52 in the base 41 to engage a similar gear 51 in bottom casing 37 as hereinafter explained. Gear 51 also turns horizontal transverse shaft 53 on which is mounted rubberized roller 54 which fits into gap 39 through a slot 55 cut in base 41.Shaft 53 is flexiblv mounted by means of two mounting brackets 56 shown in detail in Figure 7. Each bracket 56 has a spring 57 held down by member 58 and formed with a reverse bend 59 into which the shaft 53 fits. Screw 6() (Figure 7) adjusts the roller spring to set the pressure between the top and bottom rollers 54, 72. The mounting 56 permits the roller 54 to be moved slightlv upward when a card 31 passes through the gap 39.

It exerts sufficient downward force on roller 54. however. so that the card 31 is driven into the gap 3').

Also mounted in top casing 36 is a microswitch 61 having a switch arm 62 which extends down through a hole 63 in base 41 into the gap 39. When a card 31 is inserted through the slot 28 and into the gap 39. it engages arm 62 so that switch 61 starts motor 46 in a forward direction. Spaced rearwardly on base 41 is a second microswitch 66 having a switch arm 67 extending into gap 39 through hole fig. When the card 31 is driven into gap 39 until it contacts arm ó7. switch 66 reverses motor 46 and causes the roller 54 which still engages the card to reverse the direction of movement thereof and discharge the card through slot 28.

Lower casing 37 has a base 71 in which is rotatably mounted bottom roller 72 which is similar to roller 54 and which projects through a slot 73 formed in base 71 and rotates on a shaft 74 which carries the gear 51 mating with the gear 51 of casing 36. Shaft 74 may be mounted by means of mountings 76 which resemble the mountings 56 of casing 36.

Likewise mounted on panel 27 is a bracket 78 for a plurality of electronic components 79 including the power supply and one or more printed circuit boards (not shown) located in lower casing 37.

Mounted on base 41 is a transducer (head) 69 which is located over the path of movement of strip 32 and functions to read the number of pulses 33 on card 31 as well as identifving indicia to prevent substitution of cards, to display the number of pulses on the card through window 29 and to erase one pulse as the card 31 is discharged. Simultaneously with the erasure of one pulse. a relay is closed which starts the laundry machine, vending machine, etc. l'he electronic circuitry used with the head 69 is explained in detail hereinafter in this specification.

Referring to Figure 12, there is recorded on the strip 32 of card 31 a plurality of sawtooth shaped magnetic signals or pulses 33 corresponding to the number of 'credits" purchased by 'i patron. Each pulse comprises a ramp portion of relatively low slope and a step portion of relatively high slope. The sawtooth signal is employed for detecting the direction in which the card 31 is moving past the head 69.

I he magnitude of a current generated in a magnetic head, such as head 69. is a function of the rate of change of magnetic flux at the head. The polarity of the current is a function of the polarity of the rate of change of the flux. If a square pulse or any equivalently symmetrical pulse having a sufficientlv high rate of change of flux at both its leading and trailing edges were employed on card 31, it may be noted that the head would output a signal of the sime polaritv regardless of the direction in which the card is moved past the head. This is because the slope of the leading and trailing edges of such a pulse would appear to the head as being of the same polarity.For example. with the card moving in one direction. the leading edge of a square pulse passing the head would have a positive slope.

Thereafter. as the card moved in a reverse direction. the trailing edge of the same pulse would also appear to the head as a leading edge having a positive slope.

In a preferred form of the invention. a sawtooth rather than a square pulse. is used and a different result is c,btained if the slope of the ramp portion is low enough so that no signal is generated in the head as the head traverses the ramp portion at a predetermined velocity.

Llnler these circumstances. insofar as the head is concerned. it "sees" only the rapidly charring step portion of the pulse and that portion of the pulse has a well defined polarity which is I function of the direction in which the card is moving. Thus, if the card is moving in such a direction that the head first traverses the ramp portion of the pulse. it will output a sigmil of one polarity corresponding to the negative slope of the high rate of change step Fs)rtion. Conversely. if the card is moving in the opposite direction, it will first traverse the high rate of change step portion of that pulse and "see" a slope of opposite polarity.In essence. then. insofar as the head is concerned. with respect to any given pulse, it will "see" either a pulse with an infinitelv long leading edge or an infinitely long trailing edge depending on the direction in which the card is moving.

For the foregoing reasons. as shown in Figure 12A as the card 31 is moved inward of the reader 26 past head 69. the ahrupt change in each of the ramps causes a positive pulse signal. When the card is moving in a reverse direction. there is a similar sharp pulse output signal of negative characteristics as shown in Figure 17B. The output signals in either direction are used to perform the functions which have been hereinbefore generally described and which are hereinafter described in detail.

Figure 13 is a preferred block diagram for the reader 26. Figure 14 is a preferred schematic diagram of the block diagram Figure 13. it being understood that modifications therein will readilv occur to one skilled in the art. The principal components of Figure 13 block diagram as set forth in Figure 14. are detailed in Table I set out later. Values of the various components of Figure 14 are set forth in Table II set out later. it being understood that these values are merelv illustrative.

Head 69 derives signals from the card 31 inserted in the machine. Head 69 produces positive pulses as the card enters the machine and negative pulses as the card emerges from the machine. These pulses are amplified in the pre-amp section and passed either to the positive pulse amplifier (which amplifies the "up" pulses or the "in" pulses) or to the negative pulse amplifier section (which amplifies the "down" pulses or the 'outgoing" pulses). The positive pulse amplifier and negative pulse amplifier are biased in such a manner that they only amplify the pulses which are intended to pass through them. These pulses are used. in turn. to cause the up/down counter to count up or down. The "skip one pulse" is used to make possible the counting completely down to zero on the card as hereinafter explained. The upldown counter counts up until the first down pulse causes the down pulse enabler to feed a pulse into the counter which causes it to start counting down.

The same pulse sets a long delay reset so that after lapse of a preselected time period (e.g.

ten-fifteen seconds) everything is reset to zero condition. The successive 'down pulses" derived from card 31 cause the up/down counter at this time to count down sequentially to zero. However. after one down pulse has passed, as determined by the "skip one down pulse" box. a freeze pulse is presented to the 7 segment digit driver which freezes it at the number which is one less than the highest number to which the counter counted. This is an optional but preferred arrangement used in order to indicate the number of credits left on the card after it has been used. This number is displayed by the 7 segment digit until the pulse which is designated "reset pulse" from the long delay reset causes the 7 segment digit to return to zero.

When first, the counter has returned to the zero level and, second, the down pulse output is in the down direction and. third, more than one pulse has been determined on the input, these three conditions cause the "AND gate" to enable an erase circuit which enables an erase oscillator signal to head 69 and thus erases the last pulse on the card as the card is emerging from the machine. At this time, the "wash enable" activates the "wash relay" which in turn is used to start the laundry machine or vending machine.Since the erase oscillator output feeds into head 69 and the pre-amp and all the other amplifiers can upset the counting sequence. the enabling pulse for the erase oscillator is also used to bias off the negative pulse amplifier and the positive pulse amplifer so that the subsequent circuits will be immune to this interfering signal in the head. This sequence of events occurs for each insertion of the card in the machine until there is only one pulse left on the card. The single last pulse does not enter into the up/down counter because of the "skip one" pulse circuit and the counter remains at zero and the "wash relay" is not activated.

Directing attention now to Figure 14. when card 31 is inserted in the machine, transducer head 69 derives signals which are positive pulses as the card moves into the machine and negative pulses as the card moves out of the machine. These pulses are fed to the pre-amplifier and amplified by a factor of approximately 1,0()(). The output of the pre-amplifier is divided into two sections each of which consist of low-pass filters to suppress unwanted noise transients which might be present in the signal. The filtered signal is then passed into terminals 6 and 13 of I.C. 1-2 and I.C. 1-3. These two amplifiers are biased in opposite directions in order that one of them will amplify negative going pulses and one of them will amplify positive going pulses.The negative going pulses which are derived from the card as it travels out of the machine are titled "B" in Figure 14. The positive going pulses which are derived from the card coming into the machine are entitled "A" in Figure 14. The pulse polarities are depicted in the small diagrams accompanying each of the amplifiers in the Figure. At the output of the positive pulse amplifier and negative pulse amplifier. the amplitude of the wave form is approaching plus and minus five volts.At this point. the signal is introduced to standard TTL integrated circuits through resistors R-10 and R-22. The "up" pulses "A" are shaped so that at terminal 6 of l.C. 2-3 there is a negative going pulse of five volts amplitude. 1.C. 2-6 shapes the "B" pulse to a positive going pulse at terminal 12 of I.C. 2-6. I.C. 5-2 and I.C. 6-2 are used together to skip the first type "A" pulse that enters the circuit so that the first pulse of the "A" type which reaches the counter l.C. 7 at terminal 15 is pulse number two of the "A" type. The reason for skipping the first pulse will he described later. The "A" type pulses cause the counter l.C. 7 to count up from zero to the maximum count or the maximum number of credits on the card.The binarv coded output of l.C. 7 is fed to the 7 segment digit driver I.C. 4 which in turn drives the digital number displayed on l.C. 12. This is a 7 segment number of the type frequently used for digital numeric displays.

The maximum number of credits allowed in the present system is nine. Therefore. the digital indicator l.C. 12 shows "9" when a full card is inserted into the machine. As the direction of motion of the card reverses and the card starts out of the machine, negative going pulses or pulse types iXB'' commence emerging from the transducer head 69 and these pulses are fed to the counter l.C. 7.When. first. the counter I.C. 7 output indicates zero and. second. the counting sequence direction is in the down direction and. third, if more than one pulse has been fed into the system as determined by the "up" pulse enable. the coincidence of these conditions being determined in the "AND" gate. a pulse is generated by the AND gate which causes the two subsequent multi-vibrators I.C. 9 and I.C. 1() to be activated. The output of l.C. 1(1 (erase enable) activates the erase oscillator circuit consisting of T4 and the coil LI in its collector circuit. This 3.5KHz, 5 or 6 milliamp (for example) signal is transmitted to head 69 through capacitor C18 and the two back-to-back diodes D6 and D7.Diodes D6 and D7 isolate the erase circuit from head 69 when the head is being used for reading purposes. The diodes D1. D2 tied to pin 3 on I.C. 1-1, tend to limit the amplitude of the erase circuit signal so as not to damage l.C. 1-1. The amplitude of the erase signal is approximately 16 volts at head 69. Since this large amplitude signal would saturate the amplifiers and tend to disrupt the counting sequence in the subsequent circuitry. the output of I.C. 9 which occurs at the same time as the initiation of the erase signal is used to bias "off' the amplifier I.C. 1-2 and amplifier I.C. 1-3 so as not to allow any signal to come through these sections.The biasing action is achieved through the operation of bias gates designated T1 and T2 and remains in effect until after the erase signal has terminated. In other words. the time constant of I.C. 9 is slightly greater than the time constant of l.C. 10.

The first "down pulse" out of l.C. 5-1 which was used to control the direction of counting of l.C. 7 is also used to initiate the monostable multi-vibrator I.C. 11, which has a very long time constant and which determines the total length of time that the digit is displayed on l.C. 12. At the end of this time constant, a pulse is derived through l.C. 3-3 and capacitor C13 and fed to the reset terminal of counter I.C. 7. This resets the counter to zero. It also resets the circuitrv that is used to skip the first input pulse. As the series of "down" pulses commences, the counter l.C. 7 changes its output indication to correspond to the appropriate down pulse number. The display driver I.C. 4 subsequently causes the appropriate number to be displayed on the digital display I.C. 12.However. after the down counting sequence has moved one digit. the circuitry involving I.C. 8-2 generates an output pulse which freezes the number represented by the second down pulse so as to give a continuous display on I.C. 12 of the number of credits remaining on card 31.

In the foregoing description. it is noted that there is one extra pulse on card 31. The reason for this is now described. As card 31 emerges from the machine. the up/down counter I.C. 7 counts down to zero. at which time the erase enable I.C. 10 is initiated to erase a pulse on the card. However. when the counter counts to zero. there would be no more pulses on the card and there would be nothing left to erase. so an extra pulse is recorded on card 31 initially: and then when the counting sequence commences as the card enters the machine. the first pulse is skipped by the "skip one pulse" box consisting of l.C.

5-' and I.C. 6-2. When the counter counts up and then subsequently counts down to zero and the erase circuit is activated. there is still one remaining pulse on the card to be erased by the erase current.

In order to prevent card 31 from being returned to the patron when the last credit has been erased. another set of rollers may be mounted in the reader 26 which is energized from motor 46 through a clutch to drive the card to the left. as viewed in Figures 5 and 6. and into a receptacle in box 21. Thus the card 31 may be re-used after being encoded once again.

Further. the fact that the card is not returned to the patron reduces the possibility of litter from discarded cards and also any temptation for the patron to tamper with the encoding.

In the foregoing description and accompanying drawings. card 31 is motor-driven past the head 69. However. with the sawtooth pulse being encoded on the card. the motor 46 and rollers 54. 72 may be eliminated and the card 31 manually inserted in slot 38 and into gap 39 and then withdrawn. If the card is moved manually with sufficient velocitv the electronic circuitry above defined will function satisfactorily.

Moreover, the use of the sawtooth signal and circuitry responsive thereto as described herein avoids the necessity for requiring complete insertion of the card in the machine since the circuitry will still function to activate the machine even though the card is only partially inserted, one pulse being erased for each energization of the wash relay even though it is not the last pulse on the card.

Encoder 86 is used to encode cards 31 with a number of pulses 33. Such encoder is located at a central point where suitahle securitv exists. Top casing 87 is closed with a top cover 88 and mounted above bottom casing 89 with a gap 91 dimensioned for card 31. Bottom casing 89 has a front panel 92 formed with an indicator window 93 surrounded bv a bezel and also having extending therethrough the perimeter of a wheel 94 which may be manually adjusted for a given number of pulses to be encoded on to the card 31. Within casing 89 is a motor 96 having a shaft 97 here shown as projecting out one side of casing 86 and carrying a drive pulley 98 which. through belt 99. drives a plurality of speed reduction idler pulleys 101 mounted on the outside of casing 86 through belts 102.The final shaft 103 extends into the casing 89 and carries on its inner end a gear 106 which mates with a gear 118 on front bottom transverse horizontal shaft 118 on which is mounted bottom roller 119. Shaft 118 carries a gear (not shown) which meshes with gear 107 on top front transverse horizontal shaft 10X. appropriate holes being formed in the casing so that the gears can mesh. Front top roller 10C) is fixed to shaft l()8. Shaft 108 also carries one of a pair of pulleys 111 which are connected together bv belt 112. the rearward pulley 111 being fixed on rear top shaft 113 which also carries a rear top roller 114. Rollers 109 and 114 extend down through slots in the bottom of casing X7 into the gap 91 through which card 31 passes. Top shafts 108 and 113 are mounted on casing 87 by means of supports 116 which resemble the support 56 shown in Figure 7. In bottom casing 89 are similar supports 117 for bottom front shaft 118 which carries bottom front roller I 119 which mates with roller 109. The bottom rear shaft carrying bottom rear roller 123 is driven from shaft 118 via pulleys in the same manner as shaft 11. is driven from shaft 1118. Shaft 122 carries a roller 123 which mates with roller 114.

Mounted in casing 87 is a magnetic record head (transducer) 126 which is positioned to magnetically act upon the strip 32 of card 31. A photocell 127 and exciter lamp mounted in casings 87 and X9 has an upper element which views through a hole 128 in casing 87. Motor 96 drives rollers 109. 114, 119. 123 continuously while the encoder is operating. 'he photocell and limp 127 operating together indicate when card 31 is in proper position with respect to head 126 and at such time the electrical components hereinafter described generate the appropriate number of pulses (determined by the manual setting of selector switch ')4) to be recorded on card 31.

Figure 15 is the block diagram of the magnetic card recorder circuit and Figure 16 is the circuit diagram therefor. Table Ill. set out later, shows the principal components of the blocks of Figure 15 as are set forth in the circuit diagram Figure 16, and Table IV, set out later. shows representative values of the various components of Figure 16.

When the recording machine is turned on. the rollers 109, 119. 114, 123, which draw card 31 into the encoder 86 and push it out are continuously turning so that any time a card 31 is inserted, it is immediately pulled through the machine. When the leading edge of card 31 reaches photocell 127. it interrupts light from the exciter lamp and, in turn. activates the rest of the circuitrv. The output from the photocell 127 is amplified in photocell amplifiers T41 and T42. It then opens a gate in the block entitled "count inhibit" which allows the pules from the pulse generator to pass into the programmable counter.This counter has been set bv a digital decade selector switch SWI so that when the desired number of pulses has passed through the transmission gate into head 126, the count inhibit circuit slops further pulses. The block entitled "skip one pulse" enables the counter to record one more pulse on the card than has been indicated by the position of the switch SW I. 'l'he purpose of this extra pelse has been described in connection with the reader circuit. The output from the pulse generator is also fed to the box entitled "pulse shaper" which converts the pulses into a ramp shape or sawtooth wave form. (See Figure 12).The purpose of the sawtooth wave form is to cause the card reader head 69 to produce positive pulses when the card is passing into the reader and negative pulses when the card is coming out of the reader. The box entitled "record bias oscillator" T++ is required in order that the ramp section of the sawtooth wave form be recorded in a linear manncr as is normally done in direct recording of signals on magnetic tapes.

A signal from the record bins osciallator is also fed to an "erase" head 131 positioned ahead of "record" head 126 to remove any remnant magnetic signals still on card 31.

Reference is made to our copending application No. 11583/77 (Scrial No. 1572051).

TABLE I Figure 13 Block Figure 14 Principal Components Pre Amp I.C 1-1 Positive Pules Am I.C 1-3 Negative Pulse Amp I.C. 1-2 Skip One Pulse I.C. 5-2, 6-2 Up Pulse Enable I.C. 5-2, 6-2, 8-1 Down Pulse Enable I.C. 5-1 "Or" Gate I.C. 6-1 "And" Gate I.C. 6-3 Up/Down Counter I.C. 7 7 Segment Digit Driver I.C. 4 7 Segment Digit I.C. 12 Long Delay Reset I.C. 11 Skip One "Down" Pulse I.C. 8-2 Erase Enable I.C. 10 Erase Oscillator T4 Wash Enable I.C. 9, T3, I.C. 3-1 Wash Relay RY1 Bias Gate &num;1 T2 Bias Gate &num;;2 T1 TABLE II R 1 2.4 K R 14 1 M R 27 15 K 2 3.3 M 15 .3 M 28 1.5 M 3 1.6 K 16 560 29 .9 M 4 .33 M 17 1.2 K 30 13 K 5 1.2 K 18 1.2 K 31 68 6 1.2 K 19 2.4 M 32 0.5 M 7 13 K 20 3.3 K 33 0.5 M 8 1.2 K 21 .33 M 34 5.1 K 9 .91 M 22 5.6 K 35 2.2 K 10 5.6 K 23 220 36 2.2 K 11 1 K 24 1.5 K 37 3.3 K 12 680 25 1 K 13 .47 M 26 15 K C 1 1 llfd C 7 0.1 C 13 0.01 2 1 8 0.1 14 3 3 0.1 9- 0.001 15 2 4 0.01 10 0.01 16 .44 5 20 11 0.01 17 3.3 6 1 12 3 18 0.1 T 1 2N 3906 Fairchild D 1 to D 8 914 Fairchild 2 2H 3906 Fairchild L 1 Miller H 109 3 2N 3906 Fairchild RY 1 Relay 4 2N 3904 Fairchild I.C. 1-1 L 144 Siliconix I.C. 5-1 7474 Fairchild 1-2 L 444 Siliconix 5-2 7474 Fairchild 1-3 L 144 Siliconix 6-1 9015 Fairchild 2-1 9016 Fairchild 6-2 9015 Fairchild 2-2 9016 Fairchild 6-3 9015 Fairchild 2-3 9016 Fairchild 7 CD 4510 R.C.A.

2-5 9016 Fairchild 8-1 7474 Fairchild 2-6 9016 Fairchild 8-2 7474 Fairchild 3-1 9016 Fairchild 9 555 Signetics 3-3 9016 Fairchild 10 555 Signetics 3-5 9016 Fairchild 11 555 Signetics 3-6 9016 Fairchild 12 FND 507 Fairchild 4 9374 Fairchild TABLE III Figure 15 Block Figure 16 Principal Components Photocell Amp T 41, 42 Skip One Pulse I.C. 41-6, 42-3 Count Inhibit I.C. 42-1, 41-2, 43-1, 42-2, 42-4, 41 Programmable Counter I.C. 44 Decade Selector Switch SW 1 Transmission Gate I.C. 47 Mixer T 43 Record Bias Oscillator T 44 Pulse Generator I.C. 45 Pulse Shaper I.C. 46 TABLE IV R 41 0.1 M R 48 50 K Pot.R 55 30 K 42 5.6 K 49 10 K Pof. 56 10 K 43 13 K 50 1 K 57 1.2 K 44 1 K 51 10 K Pot. 58 75 K 45 10 K 52 10 K Pot. 59 1.6 K 46 0.27 M 53 .27 M 47 62 54 22 K C 41 0.1 fd C 45 0.01 C 49 0.01 42 0.1 46 3.2 50 0.0015 43 0.1 47 2 51 ().()1 44 4 48 1 T 41 2N 3904 Fairchild L 41 Miller H 104 42 2N 3904 Fairchild L 42 Miller 6333 43 2N 3904 Fairchild 44 2N 3904 Fairchild D 41 914 Fairchild I.C 41-1 CD 4049 RCA I.C. 42-3 CD 4001 RCA 41-2 CD 4049 RCA 42-4 CD 4001 RCA 41-3 CD 4049 RCA 43-1 CD 4013 RCA 41-4 CD 4049 RCA 43-2 CD 4013 RCA 41-5 CD 4049 RCA 44 CD 4018 RCA 41-6 CD 4049 RCA 45 555 Signetics 42-1 CD 4001 RCA 46 741 Fairchild 42-2 CD 4001 RCA 47 CD 4066 RCA WHAT WE CLAIM IS:: 1. A reader for use with a magnetic strip and for generating a control signal in response thereto, the strip bearing at least one magnetic signal indicative of the number of times the strip can be used in the reader to generate the control signal, the reader comprising transducer head means for selectivelv reading and erasing magnetic signals on such a magnetic strip being used in the reader, means for transporting the strip past the head means in a first direction on feeding the strip to the reader and then in a second direction to eicct the strip from the reader. the head means being responsive to said magnetic signal or signals for provi(lillg a positive pulse corresponding to the or each magnetic signal on said strip passing the head means when said strip is transported past the head means in said first direction and a negative pulse corresponding to the or each magnetic signal on said strip passing the head means when said strip is transported passed the head means in said second direction, a counter, means for incrementing the counter in response to positive pulses from the head means and for decrementing the counter in response to negative pulses and means responsive to the counter for generating said control signal when the counter indicates that the strip being read can be used at least once more to generate the control signal, and for effecting erasing bv said head means of at least one magnetic signal from the strip when the strip is transported in the second direction.

2. A reader as claimed in claim 1 wherein said incrementing and decrementing means is arranged to increment the counter in response to one less than the total number of positive pulses corresponding to magnetic signals on said strip.

3. A reader as claimed in claim 2 wherein said counter responsive means is arranged to generate said control signal in response to said counter being decremented to zero by negative pulses.

A. A reader as claimed in claim 3 wherein said counter responsive means is arranged to effect erasure by said head means of the last magnetic signal on said strip to pass said head means when said strip is transported in said second direction.

5. A reader as claimed in claim 4 wherein said incrementing and decrementing means is inhibited from incrementing and decrementing the counter during said erasure.

(i. A reader as claimed in claim 4 or claim 5 wherein said erasure is effected in response to said counter being decremented to zero.

7. A reader as claimed in anv of claims 2 to 6. wherein said incrementing and decrementing means is arranged to skip the first positive pulse from the head means so that

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **.

TABLE IV R 41 0.1 M R 48 50 K Pot. R 55 30 K

42 5.6 K 49 10 K Pof. 56 10 K

43 13 K 50 1 K 57 1.2 K

44 1 K 51 10 K Pot. 58 75 K

45 10 K 52 10 K Pot. 59 1.6 K

46 0.27 M 53 .27 M

47 62 54 22 K C 41 0.1 fd C 45 0.01 C 49 0.01

42 0.1 46 3.2 50 0.0015

43 0.1 47 2 51 ().()1

44 4 48 1 T 41 2N 3904 Fairchild L 41 Miller H 104 42 2N 3904 Fairchild L 42 Miller 6333

43 2N 3904 Fairchild

44 2N 3904 Fairchild D 41 914 Fairchild I.C 41-1 CD 4049 RCA I.C. 42-3 CD 4001 RCA 41-2 CD 4049 RCA 42-4 CD 4001 RCA 41-3 CD 4049 RCA 43-1 CD 4013 RCA 41-4 CD 4049 RCA 43-2 CD 4013 RCA 41-5 CD 4049 RCA 44 CD 4018 RCA 41-6 CD 4049 RCA 45 555 Signetics 42-1 CD 4001 RCA 46 741 Fairchild 42-2 CD 4001 RCA 47 CD 4066 RCA WHAT WE CLAIM IS: 1.A reader for use with a magnetic strip and for generating a control signal in response thereto, the strip bearing at least one magnetic signal indicative of the number of times the strip can be used in the reader to generate the control signal, the reader comprising transducer head means for selectivelv reading and erasing magnetic signals on such a magnetic strip being used in the reader, means for transporting the strip past the head means in a first direction on feeding the strip to the reader and then in a second direction to eicct the strip from the reader. the head means being responsive to said magnetic signal or signals for provi(lillg a positive pulse corresponding to the or each magnetic signal on said strip passing the head means when said strip is transported past the head means in said first direction and a negative pulse corresponding to the or each magnetic signal on said strip passing the head means when said strip is transported passed the head means in said second direction, a counter, means for incrementing the counter in response to positive pulses from the head means and for decrementing the counter in response to negative pulses and means responsive to the counter for generating said control signal when the counter indicates that the strip being read can be used at least once more to generate the control signal, and for effecting erasing bv said head means of at least one magnetic signal from the strip when the strip is transported in the second direction.
2. A reader as claimed in claim 1 wherein said incrementing and decrementing means is arranged to increment the counter in response to one less than the total number of positive pulses corresponding to magnetic signals on said strip.
3. A reader as claimed in claim 2 wherein said counter responsive means is arranged to generate said control signal in response to said counter being decremented to zero by negative pulses.
A. A reader as claimed in claim 3 wherein said counter responsive means is arranged to effect erasure by said head means of the last magnetic signal on said strip to pass said head means when said strip is transported in said second direction.
5. A reader as claimed in claim 4 wherein said incrementing and decrementing means is inhibited from incrementing and decrementing the counter during said erasure.
(i. A reader as claimed in claim 4 or claim 5 wherein said erasure is effected in response to said counter being decremented to zero.
7. A reader as claimed in anv of claims 2 to 6. wherein said incrementing and decrementing means is arranged to skip the first positive pulse from the head means so that

the counter is incremented only by any subsequent positive pulses.
8. A reader as claimed in any preceding claim wherein said transducer head means is arranged to provide said positive and negative pulses in response to saw tooth-shaped magnetic signals on the strip each having a slowly changing ramp portion and a rapidly changing step portion, said positive and negative pulses being produced in response only to said step portions either preceding or following said ramp portions in accordance with said directions of transporting the strip passed the head means.
9. A reader as claimed in any preceding claim and including display means responsive to the counter to display the remaining number of times said strip may be used thereafter for generating said control signal.
1(). A reader as claimed in claim 9 wherein said display means is operative to display said remaining number of times after a first decrementation of the counter.
11. A reader as claimed in claim 10, as dependent on claim 2 and where the reader is used with a strip bearing one more said magnetic signal than said number of times it may be used, wherein said display means is arranged to display the number in the counter immediately before and after said first decrementation.
12. A reader as claimed in claim 11. wherein said display means comprises a digital display.
13. A reader as claimed in claim 12. wherein said display means includes a driver circuit for said digital display connected to a multi-vibrator having a predetermined time constant so that the number indicating said remaining number of times is displayed lor a predetermined period of time and then reset to zero.
14. A reader as claimed in any preceding claim wherein said incrementing and decrementing means includes a first amplifier arranged to amplify only said positive pulses and a second amplifier arranged to amplify only said negative pulses.
15. A reader as claimed in any preceding claim and for use with a card having said strip extending longitudinally thereon. wherein said reader includes a casing having plates spaced apart ill I lonitudinallv extending gap slightly greater than the thickness of said card and wide enough to receive said card, said casing having a front formed with a slot in registry with said gap and dimensioned to receive said card. a reversible motor in said casing. first and second shafts each resilientlv mounted transverselv and parallel to said plates. first and second rollers each fixed to one of said shafts and extending into said gap to grip ind transport I card inserted into said slot through said gap, a first switch in said casing having first switch actuating means extending into said gap positioned to be actuated by the leading edge of a card inserted into said slot to actuate said first switch to energize said motor in a first direction, first drive means interconnecting said motor and said first shaft.

second drive means driving said second shaft from said first shaft in a direction opposite said first shift, a second switch having second switch actuating means extending into said gap a fixed distance inward of said first switch actuating means positioned to be actuated by the leading edge of said card when it has been moved bv said rollers into said gap a fixed distance to actuate said second switch to reverse said shafts. said transducer head means being located in the casing along the path of movement of said strip.
16. A reader as claimed in claim 15 in combination with an outer casing of the type normally housing the coin accepting mechanism for a coin-operated laundry or vending machine. the outer casing having a front panel formed with a pair of openings and the casing having a depth greater than said reader casing. said reader casing fitting through one of said openings the front of the reader being congruent to said front panel.
17. A reader as claimed in claim 15 or claim 16 wherein said motor is located at an end of s'iid reader casing remote from said head means and said first drive means extends longitudinally along one edge of said casing.
1S. A reader as claimed in claim 17 in which said first drive means comprises a plurality of gears in a train and means mounting said gears longitudinally spaced apart along said casing.
19. A reader according to any of claims 15 to 18. wherein said reader casing comprises top and bottom sections. each having a base. upstanding sides and a cover, and shims interposed between the longitudinal edges of said sections of a thickness slightly greater than that of said card and having inner edges spaced apart substantially the width of said card. said bases and shims defining said gap.
'(). A reader as claimed in claim 19 which further comprises mounting means for attiching said first shaft to one of said bases. said mounting means comprising a reverse band of flat spring material. said bend supporting said first shaft. wherebv said first shaft can flex toward and awav from said base so that said first roller can grip and then roll over said card.
21. A render as claimed in claim 20 which further comprises an adjustment screw to adjust the roller pressure. said screw passing through said spring material and threaded into said base.
22. A reader as claimed in any of claims 15 to 21 as dependent on claim 12, wherein said front of the reader casing has a window located for observation of the digital display.
23. A reader as claimed in any preceding claim and including a relay energised in response to said control signal and for energising in turn a laundry or vending machine in which the reader is incorporated.
24. A laundry or vending machine incorporating a reader as claimed in any preceding claim and arranged to be energised in response to generation of said control signal.
25. Encoding and reading apparatus comprising a reader as claimed in any of claims 1 to 23 in combination with an encoding means for encoding said magnetic signals on said magnetic strip.
26. Apparatus as claimed in claim 25 wherein said encoding means further comprises a manually settable switch means manually settable to a position corresponding to the number of times it is desired to use said strip for generating said control signal and means responsive to said switch means for encoding on said strip a corresponding predetermined number of said magnetic signals.
27. Apparatus as claimed in claim 26 wherein said corresponding predetermined number of said magnetic signals exceeds by one the number of times it is desired to use said strip for generating said control signal.
28. A reader for use with a magnetic strip borne on a card, substantially as hereinbefore described with reference to Figures 2 to 8. and 12 to 14 of the accompanying drawings.
29. Encoding and reading apparatus comprising a reader as claimed in any of claims 1 to 23 and 28 in combination with an encoder substantially as hereinbefore described with reference to Figures 9 to 11. 15 and 16 of the accompanying drawings.