GB2174228A - Method of distinguishing chips - Google Patents

Abstract

In a method of distinguishing chips, each chip 8 contains an insert made of an electrically conductive or magnetic material, different chips having different inserts, and the chips are passed adjacent inductive or capacitive sensor means 2,3 which distinguish chips on the basis of different electrical signals generated in the sensor means by the different inserts in the passing chips. Use of an electromagnetic sensor overcomes the problems associated with known optical sensors, in that dirt on the chips or use of patterned chips does not affect the operation of the sensor. <IMAGE>

Description

SPECIFICATION Method of distinguishing chips The present invention pertains to a method of distinguishing chips. More particularly it relates to sorting the chips used in gaming establishments to represent money, into heaps or piles which each contain chips of only one denomination.

There is already known a machine which is used in casinos world-wide for the purpose of sorting chips. This machine operates by picking up the chips on a conveyor belt, which takes them past an optical scanning device, which in turn gives information about the colour of the chip to a computer. The colour of the chip is used to denote the owner for the time being and/or the value of the chip when played. The chips are transported past the heaps of sorted chips. The computer triggers a solenoid when a chip passes the appropriate heap and the chip is forced into the heap by the solenoid.

The major drawback with this prior machine is that the chips and the optical scanning device both become soiled as result, amongst other things, of the very dirty atmosphere created by tobacco smoking in the establishments. This results in a progressively higher rate of incorrect sorting which eventually becomes unacceptable and must be remedied by servicing. A further disadvantage of the known optical sorting machine is that some colours are not always readily distinguishable to the optical device. Another disadvantage is that some chips are marked with symbols of a colour or colours different from the chip colour and these symbols sometimes cause confusion for the machine. In paricular, the present machine is unable to sort certain types of 'cash' chip, which have a central insert and radially extending coloured stripes.

According to one aspect of the present invention there is provided a method of distinguishing chips, wherein each chip contains portion made of an electrically conductive or magnetic material, such that different chips have different electrical or magnetic characteristics, and the chips are passed adjacent inductive or capacitive sensor means which distinguish chips on the basis of different electrical signals generated in the sensor means by the passing chips.

According to another aspect of the present invention there is provided chip sorting apparatus comprising an inductive or capacitive sensor, means for passing chips adjacent the sensor, which sensor provides different electrical signals when passed by chips having different electrical or magnetic characteristics, and selection means, connected to receive the signals, for distinguishing different chips on the basis of the different electrical signals provided by the sensor. In a preferred embodiment the portion in each chip is in the form of an insert.

In a preferred embodiment the sensor means are inductive sensor means.

In a preferred embodiment the portion in each chip is made of a ferromagnetic material.

Preferably all the chips of a given colour have similar electromagnetic characteristics.

Embodiments of the invention need not suffer from a degradation in performance caused by airborne contamination as does the optical scanning device. Embodiments of the invention can avoid difficulties in sorting chips which are of similar colours. Embodiments of the invention do not suffer from the difficulties of sorting chips which are marked with symbols of a colour or colours which are different from the colour of the chip itself.

The present invention will now be described by way of example, with reference to the accompanying drawings, wherein: Figure 1 shows in diagrammatic form apparatus according to one embodiment of the present invention, and Figure 2 shows in diagrammatic form apparatus according to a second embodiment of the present invention Referring now to figure 1, an oscillator 1 is connected to a coil 2 which is wound on a former 3. The construction of former 3 may include a magnetic material or it may not.

Chips 8 are passed adjacent the coil 2 on a conveyor belt 9. Each chip contains an insert made of an electrically conductive or magnetic material, different chips having different inserts. For example, all the chips of one denomination will have an insert of one size, while all the chips of another denomination have an insert of another size. Chips passing adjacent the coil cause changes in the oscillations in the coil. The oscillator and coil are connected also to an interface 4 which preferably measures the amplitude, frequency and phase of the oscillations produced by the oscillator and coil. The interface converts the information about the measurements into a form suitable for passing to the computer 5. The computer uses the information passed to it from the interface to decide into which heap 7 each chip 8 should be placed.The computer is programmed to process the information supplied so as to determine the denomination of the chips by the effects of the metal inserts on the electrical properties of the inductive component. The computer knows the distances along the conveyor 9 from the coil to the various heaps of chips and using information from a transducer 10 which monitors the progress of the conveyor, is able to energise the actuators 6 at the correct times so that the chips are placed in the correct heaps.

It is not necessary for the inserts to be visible, that is to say they may be embedded in the chips. Alternatively the electromagnetic characteristics of the chips may be introduced by making the chips of a material including electrically conductive or magnetic particles. In the case of a magnetic insert, the insert may be ferromagnetic, diamagnetic or paramagnetic, although ferromagnetic is preferred (for example a ferrite or a soft iron insert). In another example, the insert may be a permanent magnet. As another alternative, the insert may comprise more than one part, such as concentric rings of dimensions encoding the denomination of the chip.

Figure 2 shows another embodiment of the invention, featuring a different detection system. In figure 2 a computer 15 controls the application of electrical energy to a coil 12 on former 13 from an energy source 11 by means of a switch 16, to cause energy pulses. Because some of this energy is transferred to the metal insert, where it manifests itself as a circulating and decaying electric current, there is induced in the inductive component by the circulating current an electrical signal. This signal is used as the basis for the information transferred to the computer and hence for the sorting of the chip. After the switch has been first closed and then opened on instructions from the computer, the interface 14 preferably measures the amplitude, frequency, phase and rate of decay of the electrical signal induced in the coil, and transfers this information to the computer.The chip sorting mechanism in this embodiment is the same as described above in figure 1.

If desired the chips may be held briefly stationary as they are passed adjacent the sensor.

Alternatively, instead of using an inductive system, a similar system based on a capacitive sensor may be used. This is obviously only applicable to chips having electrically conductive rather than magnetic inserts, although it would be possible to construct a sensor comprising a pair of spaced capacitor plates, chips having different dielectric properties being passed between the plates.

According to another aspect of the invention there is provided a strongbox, having an aperture for receiving currency in the form of banknotes, wherein the strongbox contains identification means for distinguishing between different banknotes, for example on the basis of size or shape. Preferably the strongbox also includes means for recording the total sum of money received by the box, as detected by the identification means. Preferably the strongbox contains means for checking that the banknotes have a metal filament.

Claims (19)

1. A method of distinguishing chips, wherein each chip includes a portion made of an electrically conductive or magnetic material such that different chips have different electrical or magnetic characteristics, and the chips are passed adjacent inductive or capacitive sensor means which distinguish chips on the basis of different electrical signals generated in the sensor means by the passing chips.

2. A method as claimed in claim 1, wherein the portion of each chip is made of an electrically conductive material.

3. A method as claimed in claim 1 or 2, wherein the portion of each chip is made of a magnetic material.

4. A method as claimed in claim 3, wherein the portion of each chip is made of a ferromagnetic material.

5. A method as claimed in any preceding claim, wherein the sensor means are inductive sensor means.

6. A method as claimed in claim 5, wherein the sensor means include inductor means for generating circulating electric currents in the passing chips.

7. A method as claimed in claim 2, wherein the sensor means are capacitive sensor means.

8. Chip sorting apparatus comprising an inductive or capacitive sensor, means for passing chips adjacent the sensor, which sensor provides different electrical signals when passed by chips having different electrical or magnetic characteristics, and selection means, connected to receive the signals, for distinguishing different chips on the basis of the different electrical signals provided by the sensor.

9. Apparatus as claimed in claim 8, wherein the sensor is an inductive sensor.

10. Apparatus as claimed in claim 9, including inductor means for generating circulating electric currents in the said passing chips.

11. Apparatus as claimed in claim 10, wherein the inductor means are provided by the sensor.

12. Apparatus as claimed in claim 8, wherein the sensor is a capacitive sensor for detecting different electrical characteristics of passing chips.

13. Apparatus as claimed in any one of claims 8 to 12, wherein the means for passing chips adjacent the sensor comprise a conveyor belt.

14. A chip for use in a method as claimed in any one of claims 1 to 7, or with apparatus as claimed in any one of claims 8 to 13, comprising a body and an electrically conductive or magnetic insert wholly enclosed within the body.

15. A chip for use in a method as claimed in any one of claims 1 to 7, or in apparatus as claimed in any one of claims 8 to 13, comprising a body made of material including electrically conductive or magnetic particles

16. A chip as claimed in claim 14 or 15, wherein the body of the chip is coloured, chips of the same colour having the same electrical or magnetic characteristics.

17. A method of distinguishing chips substantially as hereinbefore described with refer ence to figure 1 or figure 2 of the accompanying drawing.

18. Chip sorting apparatus substantially as hereinbefore described with reference to figure 1 or figure 2 of the accompanying drawing.

19. A chip substantially as hereinbefore described with reference to figure 1 or figure 2 of the accompanying drawing.