1. An automatic dispensing system comprising dispensing apparatus having product dispensing means and a key having a value storage unit and means to initiate dispensing from the dispensing apparatus, means for synchronously magnetically coupling the dispensing means of said apparatus with the value storage unit of said key to reduce the stored value as dispensing progresses, said coupling means comprising a rotatable permanent magnet coupled with said value storage unit and a cooperating rotatable permanent magnet coupled with said dispensing means, means for detecting slip in said magnetic coupling to stop dispensing of the product by said dispensing means when slippage exceeding a predetermined value occurs, said detecting means comprising first pulse generating means kinetically coupled with said dispensing means to generate a pulse with each selected increment of operation of said dispensing means, second pulse generating means kinetically coupled with said value storage unit to generate a pulse with each corresponding increment of devaluation of said storage unit, and circuit means receiving and comparing said pulses from said first and second pulse generating means and providing a signal to stop said dispensing means when the pulse sequence received from said second pulse generating means does not correspond to the pulse sequence received from said first pulse generating means.
2. Automatic dispensing system in accordance with claim 1, wherein said magnets comprise disc shaped permanent magnets with more than two poles of alternating polarity distributed over the periphery of the disc, the magnets being face magnetized, so that the lines of force extend from the adjacent surfaces of the discs.
3. Automatic dispensing system in accordance with claim 1, wherein the key comprises a cylinder the surface of which has flattened portions.
4. Automatic dispensing system in accordance with claim 3, wherein one end portion of the key has locating means distributed around its periphery and the keyhole of the dispensing apparatus has complementary locating means which coincide in position with locating means of the key.
5. Automatic dispensing system in accordance with claim 4, wherein the locating means of the key consist of recesses and those in the keyhole consist of radially adjustable pins, and wherein said dispensing apparatus has a control element that cooperates with said pins and is movable manually into an end position by the user when the pins engage with the recesses to initiate the operation of the dispensing means.
6. Automatic dispensing system in accordance with claim 5 for the dispensing of liquid fuel by means of a pump, wherein the control element in an end position starts up a pump motor of the fuel dispensing apparatus and a magnetic valve in a circulating conduit is opened, so that the fuel circulates.
7. Automatic dispensing system in accordance with claim 1, wherein the second pulse generating means kinetically connected with the value storage unit of the key comprises a disc-shaped radially magnetized permanent magnet of which the poles are distributed around the periphery of the disc, so that the lines of force are in the plane of the disc and radially emergent, and the vending machine is provided with a switch of which the position is fixed and which, when the key has been inserted in the keyhole, is located in the zone of action of the radially magnetized permanent magnet to produce control pulses on the rotation of the said radially magnetized permanent magnet.
8. Automatic dispensing system in accordance with claim 1, wherein the first pulse generating means kinetically connected with the dispensing means of the apparatus comprises at least one permanent magnet of which the position is fixed, and in the zone of action of said magnet a switch also fixed in position, and a rotatable screening system kinetically coupled with said dispensing means and having screening means that passes between said magnet and said switch to actuate the switch and thereby generate pulses as said screening system rotates.
BACKGROUND OF THE INVENTION
This invention concerns automatic self-service systems, in which a vendible product such as gasolene or diesel fuel or a service such as automobile washing can be obtained by a customer having a key, this key being used to operate appropriate dispensing apparatus. Systems are known in which coin operated dispensers are rendered operative by a key, each customer having a numbered key which engages a lock numbered to correspond with his key number. With this system each customer must have a different key and the dispenser a lock for each key, so that expensive and complicated mechanisms are essential. Further, this self-service system is practicable only with one form of dispenser, and in the case of gasolene purchase a customer can use his key only at one dispensing pump.
An object of this invention is to provide a self-service system in which the holder of a key can obtain goods from any dispenser adapted to the system. Another object is to provide a system in which the key entitles the key holder to obtain goods up to a certain maximum monetary value as distinct from quantity. Thus, in the case of gasolene, a key holder can select a required grade of fuel which will be delivered in quantity according to value.
A further object is to provide a key which can be used to operate a dispenser and on which the monetary value of goods or the like delivered is indicated on a tally counter, the key being purchased for a certain price and which is ineffective in operating a dispenser after goods have been delivered to the value paid.
A still further object is to provide a system in which an effective and tamper-proof sensing means is provided, operating by magnetic co-operation between the key and the dispenser.
SUMMARY OF INVENTION
According to the invention the automatic dispensing means comprises a value storage unit having means to initiate dispensing from a dispensing apparatus, impulse transmitting means in said unit to co-operate with the dispensing apparatus to effect dispensing devaluation means in said unit to reduce the stored value as dispensing progresses, said devaluation means including a rotatable permanent magnet for magnetic connection with a rotatable permanent magnet on the automatic coin-operated vending apparatus or machine, and coupled to a dispensing unit thereof, each of the permanent magnets being kinetically connected with at least one control device which produces control pulses dependent on the rotary movement of the permanent magnets and which are mutually compared in relation to their pulse sequence, the dispensing unit being rendered operative in the event of a synchronous pulse sequence but inoperative in the event of an asynchronous pulse sequence.
BRIEF DESCRIPTION OF THE DRAWINGS
An embodiment of the invention is illustrated schematically in the accompanying drawings, in which:
FIG. 1 is an enlarged view of a key;
FIG. 2 is a longitudinal section through the key illustrated in FIG. 1, and also a cut out portion of an automatic coin-operated vending machine into which the key can be inserted;
FIG. 3 is an end view of the key, and
FIG. 4 shows a detail from FIG. 2, as viewed in the direction indicated by an arrow A.
DESCRIPTION OF PREFERRED EMBODIMENTS
The key shown in the drawings has a housing 1 of non-magnetic material, for example aluminum, of substantially cylindrical shape, with a longitudinal axis 5 (FIG. 3) and three flattened portions 2, 3 and 4. The flattened portion 4 contains a window 6 through which digits of a counting mechanism are visible. Within the housing 1, and slightly off-center with respect to the axis 5, a shaft 8 is mounted so as to be rotatable about an axis 7, the shaft carrying permanent magnets 9 and 10 at its opposite ends. On the shaft 8 a counting unit 11 is mounted having four disc drums. A ball 12 serves as an axial thrust bearing. The housing 1 is closed at one end by a plate 13, and at the other by a cover 14 of brass or other non-magnetizable material. The cover 14 which is of cylindrical shape, performs the same function as the usual ward of a safety-type key and is provided for this purpose with a number of locating means such as marks 15 in the form of recesses on its outer surface. An arresting device (not shown) ensures that the magnet 10, and thus the counting unit, can be rotated only in the direction shown by the arrow 18 in FIG. 3. In FIG. 3 the cover 14 of the key has been omitted. The disc-shaped permanent magnet 9, which forms a part of a magnetic clutch, has more than two poles which are distributed with alternating polarities around the periphery. The magnet 9 is face-magnetized, so that the lines of force 19 shown as broken lines in FIG. 2, extend from the front surface of the disc. The permanent magnet 10 forms part of a control device which in a manner to be explained later constantly ensures that the dispensing unit of the automatic coin-operated vending machine can be rendered operative only with an appropriate key of which the value storage unit has not yet run out. This permanent magnet 10 serves to emit continuous pulses during the devaluation of the key. In the example shown, the magnet 10 has six poles distributed around its periphery with alternating polarity. This magnet 10 is magnetized radially, so that the lines of force 20 shown as broken lines in FIG. 4 are in the plane of and extend from the magnet 10. The magnets 9 and 10 are non-rotatably mounted on the shaft 8, and can only be rotated in one direction, in which the value storage unit, which in this example is in the form of the counting mechanism 11, is devalued. The counting mechanism can be rotated back from any selected number. In the example shown the key is intended to represent a total value of 500 francs, so that with the unused key the digits "5,0,0,0" will be visible in the window 6. In the key shown in FIG 1 a devaluation of 20 centimes has taken place, so that the key shows a value of Frs. 499.8.
Those parts of the machine which concern the invention will now be explained. From the price counting mechanism of a fuel pump, a rotatable shaft 21 leads to a connection 22 for the key above described. One revolution of the shaft 21 corresponds to one operation step of the price counting mechanism on the fuel pump, for example equivalent to 1 franc. The shaft 21, through a transmission gearing (not shown), drives a shaft 23 so that the said shaft 23 rotates 10 times the rate of rotation of the shaft 21. A permanent magnet 24 is mounted on the shaft 23, which magnet is constructed on the same lines as the permanent magnet 9 on the key and which forms the second part of the magnetic clutch which comprises the magnets 9, 24. The magnetic lines of force of the magnet 24 are also referenced 19. Owing to the method of polarization of the two magnets 9 and 24, the same effect is obtained as in the case of clutch elements with spur tooth gearing. A protective wall 25 of non-magnetic material is provided in the vicinity of the magnet 24. Around the wall 25 is a ring 26 to serve as a keyhole for the key. The ring 26 has radially adjustable locking pins 27 which can be adjusted by a rotatable outer ring 28, and which comprise locating means complementary to the means 15. The ring 28 has a handle 29 and a contact arm 30 and can be turned in either direction between two limit positions. In one of these positions the locking pins 27 are in their innermost position, as viewed radially, while the contact arm 30 rests against a contact 31, while in the other position the contact 30, 31 is open and the locking pins 27 have been moved radially outwardly beyond the internal surface of the ring 26. In this position the key 32 can be inserted axially into the ring 26 in a marked single position. The said marking (not shown) may consist, for example, of a notch on the ring 26 and on the key 32. A screening system 33 is fixed to the shaft 21, which system includes a cylindrical cage with a number of screening arms 34 which consist of a magnetizable material. The screening system 33 contains at least one fixed permanent magnet 35 having magnetic lines of force 36. Radially outside the screening system 33, and opposite to the magnet 35, is a switch 37 in the zone of action of the said magnet, and constructed, for example, as a reed contact switch. If a screening arm 34 is situated between the magnet 35 and the switch 37, the magnetic field does not affect the switch 37, which changes over into its other switching position. In the example, the screening system 33 has six screening arms 34 and two angularly staggered magnets 35 are provided. Opposite the two magnets also are two switches 37. This system has been selected in order to obtain accurate pulse sequences always, resulting from the closing of one switch accompanied by the opening of the other switch. The screening system 33 with magnet 35 and switches 37 constitute a control system provided on the automatic coin operated vending machine, for example on the petrol pump. On the rotation of the shaft 21 pulses are continuously produced by the switch 37 and are conveyed via lines 38 and 39 to comparison device 40. A second control device is formed by the magnet 10 on the key 32, and a switch 41 provided on the automatic coin-operated vending machine. If the key 32 has been inserted in the cylinder (keyhole) 22 on the machine, then the permanent magnet 10, as shown in FIG. 2, is positioned opposite the switch 41 and thus in the zone of action of the magnet 10. The switch 41 is a reed contact change-over switch. On the rotation of the magnet 10 the switch 41 is continuously switched over, and on each occasion emits pulses which are conveyed to the comparison device 40 via connecting lines 42, 43 and 44. If the pulses take place through the switches 37 and 41 and the lines 38, 39, 42, 43 and 44 respectively in the same pulse sequence, a slip-free coupling is obtained between the permanent magnets 9 and 24. If slip occurs between the two magnets 9 and 24 the pulse sequence is disturbed.
The machine interacts with the key in the following manner: The key 32 is inserted, in the pre-selected position, into the keyhole 22, until the cover 15 meets the wall 25. The ring 28 is then rotated by the handle 29, in which operation the locking pins 27 engage the recesses 15 of the key, fixing the same in position in the machine. If an incorrect key is used, the appropriate recesses 15 of the key will not be opposite the locking pins 27, and the ring 28 cannot be moved into the appropriate final position in which the contacts 30 and 31 will be closed to close an electrical circuit which switches on a pump of the fuel dispensing apparatus (not shown). The flow of fuel due to the pump operation is also opened by a magnetic valve in the fuel dispensing apparatus. As long as the valve at the outlet of a hose from the fuel dispensing apparatus to a consuming tank is closed, no fuel is taken, and the fuel circulates within the fuel dispensing apparatus. As soon as fuel is taken, the shaft 21, driven from the price counting mechanism of the fuel dispensing apparatus, rotates, as a result of which the shaft 23 will be driven in the direction of rotation shown in FIG. 2. The counting mechanism 11 of the key 32 is driven in a slip-free manner by the clutch magnets 9 and 24. On each revolution of the magnet 10 six pulses will be produced in the switch 41. According to the number of screening arms 34 and the number of permanent magnets 35 used and the corresponding number of switches 37, a corresponding number of pulses per rotation of the shaft 21 will also be generated in the fuel dispensing apparatus. This pulse sequence is monitored in the electronic comparison unit 40. When the pulse sequence remains constant the dispensing unit for the supply of fuel remains operative. If a slip occurs in the magnetic clutch the pulse sequence received from the switch 41 will differ from that received from the switch 37 and this difference will be detected by the comparison device 40 which thereupon provides a signal to close the magnetic valve provided in the fuel dispensing apparatus. The fuel dispensing unit of the machine is thus switched off. The aforementioned disturbance to the pulse sequence occurs as soon as a slip amounting to an angle of rotation of 60° takes place in the magnetic clutch, since the magnet 10, as shown in FIG. 4, will then already lag by one-sixth in the pulse sequence. As the shaft 21 starting from the price counting mechanism performs one rotation when 1 franc's worth of fuel has been sold, one rotation of the magnet 10 corresponds to a value of 10 centimes, owing to the gear ratio of 1:10 between the shafts 21 and 23. One rotation of the magnet 10 from one pulse to the next, i.e., by 60°, thus corresponds to a value of approximately 1.6 centimes.
A slip in the magnetic clutch 9 and 24 occurs when the value storage unit of the key 32 is devalued, i.e., when the counting mechanism 11 in the example shown has moved back to zero. In this position, in which it has run off, the counting mechanism is blocked.
If an already devalued key 32 is inserted in the keyhole 22, the mechanism runs off in the same way, with the difference that as soon as the magnet 24 starts up a slip occurs in relation to the magnet 9, and the previously opened magnetic valve is again closed. With the use of a devalued key, therefore, it would theoretically be possible, under the least favorable circumstances, for 1.6 centimes' worth of fuel to be extracted from the coin-operated automatic vending machine. To enable even this to be prevented, a retarding element could be provided in the machine to ensure that fuel could only emerge after a short time lag.
Other switches could be used in place of reed contact switches 37 and 41. The example illustrated also shows two different forms of control device. The control device 33 to 37 in the machine makes use of a magnetic field 36 which is in a permanent position and is alternately screened or not by the switch 37 via the screening systems 34. In the case of the other control device (FIG. 4) the switch 41 alternately enters magnetic fields of alternating polarity of the rotating permanent magnet 10. It would also be possible for an additional fixed permanent magnet to be provided underneath the switch 41 (FIG. 4). This magnet would act continuously on the switch 41, in which case the magnetic field of the additional magnet would be continuously influenced by the rotating permanent magnet 10.