IMPROVEMENTS IN OR RELATING TO REEL MECHANISMS FOR GAMING MACHINES

Abstract: Each reel (10) has a code (26 or 28) unique to each of a plurality of angular stop positions of the reel to enable sensing of the random position in which the reel stops. Each code has two series of aperture locations (22, 24) arranged to serially transmit coded information by passing light from sources (14, 16) to receivers (18, 20). Sensing therefore requires to take place just prior to stopping of the reel, with a minimum number of sensing components. A microprocessor is programmed to process the coded information and check for a winning combination of symbols on the reels.

Description: Improvements in or relating to Reel Mechanisms for Gaming Machines This invention is concerned with improvements in or relating to reel mechanisms for gaming machines, i.e. machines for playing games of chance. One commonly known type of gaming machine is the fruit machine. In gaming machines of the type having a plurality of rotatable reels each carrying a series of symbols around its axis of rotation, for example around its outer peripheral edge, the reels are spun and stopped at any randomly selected angular positions. A symbol on each reel is then visible through a window of the machine to the player and the combination of symbols determines whether or not a prize is won. Various arrangements have been proposed for sensing the angular positions of the reels so as to determine the winning combinations. One proposed arrangement includes a sensing disc fixed for rotation with each reel and having an arrangement of holes unique to each angular stop position of the reel. At one side of the disc a source of light is provided and a plurality of photocells are radially arranged at the other side of the disc. When the reel comes to rest at any randomly selected angular position the unique arrangement of holes for that position transmits light to respective ones of the photocells, the latter producing a coded arrangement of electrical signals which are utilised to indicate the angular stop position. Such an arrangement requires a considerable number of photocells to enable a sufficient number of codes to be obtained corresponding to the number of symbols. A further proposed arrangement includes a sensing disc fixed for rotation with each reel and having a plurality of holes arranged in an annular fashion. At the radial position of the holes a source of light is provided at one side of the disc and a photocell at the other side of the disc such that an electrical pulse is generated by the photocell each time a hole travels through the path of light. A counter is provided in association with each reel for counting the number of pulses thus determining at any one time the angular position of the respective reel. This arrangement requires a continuous check of the reel and also appropriate electrical circuitry enabling a count to be carried out, means for resetting a counter after each revolution of the reel and means for translating information from the count. The term "energy" as used hereinafter in the Specification is to be construed as embracing that which can be generated from a source, can be transmitted through the atmosphere, and can change the condition of a sensor placed in the path of transmission, and the transmission of which can be affected by the positioning of a solid member in said path For example the term is intended to embrace at least light, sound and magnetic flux. The present invention provides a reel mechanism for use in a gaming machine, said mechanism comprising a rotatable part, and sensing means having a source of energy as hereinbefore defined and means responsive to said energy, the rotatable part having means in the form of a code unique to each stop position thereof, each code being arranged to permit serial data transmission of energy from the source to the responsive means during travel of the rotatable part in the path of energy from the source, and means being provided for receiving electrical outputs from the responsive means to register the stop position of the rotatable part. The present invention also provides a reel mechanism for a gaming machine, said mechanism comprising a plurality of rotatable assemblies, a member of each assembly having a series of symbols arranged in an equi-spaced fashion around its axis of rotation and means for sensing the combination of symbols visible to the player, said sensing means comprising a source of energy as hereinbefore defined and means responsive to said energy, a part of each rotatable assembly having means in the form of a code unique to each stop position of the rotatable assembly, each code being arranged to permit serial transmission of energy from the source to the responsive means during travel of said part in the path of energy from the source, and means being provided for receiving electrical outputs from the responsive means to register the angular position of the rotatable assembly. Preferably each code comprises two series of locations through which energy can be transmitted, each series comprising transmission locations which are angularly spaced apart but at the same radial position, the angular position of both series corresponding to one another, and a predetermined number of angular positions being provided for the transmission locations in each code, each series of transmission locations having a respective responsive means aligned therewith, the code being defined by the presence of a transmission location in a selected one of the series at each angular position. Preferably also, each code includes a coding indicative of the start of the code for the respective stop position, the coding preferably comprising two transmission locations radially aligned at a further angular position at the radial positions of the respective series of transmission locations. Alternatively, each code comprises a series of locations through which energy can be transmitted angularly spaced apart at one radial position, a predetermined number of angular positions being provided for the transmission locations in each code, and the code being defined by the presence of a transmission location in a selected angular position, the means for receiving the electrical outputs from the responsive means being arranged to produce a signal at constant intervals of time, which signal differs in accordance with the presence of a transmission location. Preferably each code includes a coding indicative of the start of the code for the respective stop position, the coding preferably comprising a transmission location shaped to produce a different output from the outputs of the other transmission location or locations ofthe code. The source of energy may comprise a light source, for example in the form of one or more light emitting diodes, with the responsive means comprising light sensitive devices, for example in the form of photo transistors. Where each code comprises a series of aperture locations at one radial position only one light sensitive device may be required, with optical fibres arranged between the light sensitive device and the desired locations at the respective rotatable parts, as the angular position of only one part is sensed, at any one time. Where each code comprises two series of aperture locations, one light sensitive device may be provided for each series, with an optical fibre arrangement extending between the respective light sensitive device and the desired locations aligned with the respective series of aperture locations of each rotatable assembly. Alternatively, the source of energy may comprise a magnet arrangement with the or each responsive means in the form of a Hall effect transducer, a screen for the magnetic flux being provided on the or each rotatable part. Further the source of energy may comprise one or more ultrasonic transmitters with the responsive means comprising one or more ultrasonic receivers. Advantageously the reel mechanism includes a control system which controls operation of the or each sensing means immediately before the respective rotatable part is due to be stopped and which processes the information obtained from the sensed code so as to determine the angular position in which the rotatable part stops. Preferably the control system processes the information with a -self-checking function such that the rotatable part is allowed to move to a further angular stop position if a sensed code is not acceptable. An embodiment of the present invention will now be described by way of example only with reference to the single figure of the accompanying drawings, which is a side view of part of a reel of a gaming machine showing codes for certain angular stop positions. A gaming machine comprises a set of three or four reels 10, only one of which is shown in the drawing, and each of which has a plurality of symbols, usually representative of different kinds of fruit, equi-spaced around its peripheral edge. The reels 10 are separately mounted to be rotatable relative to one another in a conventional fashion when the machine is operated and each is arranged to stop rotating by random stopping means comprising a peripherally toothed disc (not shown) mounted for rotation with the reel, and a latch or stop (not shown) engageable in a random one of cutouts or notches between adjacent teeth of the disc. The notches correspond in number to the number of stop positions of the respective reel, each stop position having an associated symbol which is displayed through a window of the gaming machine when the reel stops rotating, to be visible to the player. Any conventional arrangement for producing the random periods of rotation of the reels may be utilised. Alternatively the stop positions may be randomly predetermined and means provided for stopping the reels where desired. The combination of symbols visible through the window determines whether or not the player should receive a prize and sensing means is associated with each reel to determine the angular position of the reel when stopped. Each sensing means is mounted on a U-shaped member 12 which in turn is connected to a printed circuit board (not shown). The sensing means comprises a pair of light sources in the form of light emitting diodes (LED's) 14, 16 spaced apart along the length of one of the legs of the member 12 and a pair of light sensitive devices, for example in the form of photo transistors 18, 20, positioned on the other leg of the member 12 to be in alignment with the respective LED's 14, 16. The member 12 is so arranged relative to the respective reel 10 that the latter during rotation passes through the gap defined between the legs of the member 12. On each angular stop position of the disc 10 there is provided a code unique to the stop position and defined by a selected arrangement of apertures formed in the reel. The apertures are arranged in two series of aperture locations, each series 22, 24 comprising aperture locations which are angularly spaced apart but at the same radial position, the series 22, 24 being radially spaced apdrt and the angular positions of both series corresponding to one another. The innermost series 22 is positioned to be capable of alignment with the LED 14 and the photo-transistor 18 while the outermost series 24 is capable of aligning with LED 16 and the photo-transistor 20. Only two codes 26, 28 are shown for reasons of clarity. Each of the codes on the disc 10 includes a start coding providing two radially aligned apertures 30, located one in each of the series 22, 24, and as this is the only position in any code where an aperture is provided in each series it is solely representative of the start of a code. To provide a sufficient number of codes for a conventional number of stop positions each code involves an aperture located in either of the series 26, 28 at each of five angular positions, such that the code will provide five bits of information providing a '1' or '0' reading in binary form. For example if the series 22 is arranged to provide a reading of 1 while the series 24 provides a reading 0 then the code 26 will comprise 11011 whereas the code 28 will comprise 10011. Any code can only be sensed during rotation of the reel 10, for example in the direction of arrow A, and therefore the pulse code produced by the photo-transistors 18, 20 sensing the location of the apertures in a code provides a series data transmission. The LED's 14, 16 and the photo-transistors 18, 20 are in electrical circuit with a control system including a microprocessor which is adapted to process information obtained from the photo-transistors and thus determine the angular positions of the reels. As each code is unique to a particular stop position it will be appreciated that no continuous check need be made by the sensing means. The microprocessor is arranged to operate the sensing means immediately before the reel 10 is due to cease rotating, and the code then read by the sensing means corresponds to the stop position displayed through the window of the gaming machine. The control system is self-checking in that a code will only be accepted and thestopping means allowed to operate if a first pair of apertures 30 are sensed followed by five bits of information and a second pair of apertures 30 signifying the start of the next code and correspondingly the end of the previous code. With this arrangement it will be appreciated that if the latch or stop does not engage properly in a notch and is bounced back on to the periphery of the toothed disc the sensing means will not read the appropriate number of bits of information, the code will not be registered, and the reel will be allowed to - rotate until a correct reading is taken indicating proper functioning of the latch or stop. Also if the reel runs on with the latch or stop not in its notch, a new code is read and replaces the code previously registered. The processor is programmed to take two readings at each angular location in each code being read. The first reading is taken and stored and after an appropriate delay the second reading is taken and compared with the first. Only when the readings match will the processing of the information then commence as otherwise it may be that the readings have been affected by spurious electrical signals. If the readings do not match they are discarded and a further pair of readings taken. When a pair of readings are found to match, the reading (Reading 1) is stored and passed to a further store (to become Reading 3). In accordance with the processing programme Reading 1 should then be compared with a previously stored Reading 2 but if the process is still in the stage of being set up there is no stored Reading 2 and thus although the programme of processing the information continues for a cycle the information processed in the cycle will be of no consequence except that, at the end of the cycle, the Reading 3 is stored in the processor as Reading 2. After a pair of matched readings have been obtained a new Reading 1 is stored and passed to said further store to become Reading 3 and the Reading 1 is compared with the stored Reading 2. If the readings match no further action takes place at this time as this is indicative that there had been no change in the output signal from the respective photo-transistor and that therefore no code aperture has passed thereby. If the readings do not match the processor is programmed to then determine if Reading 1 is such as has been caused by detection of the leading edge of a pulse from the respective photo-transistor. If this is the case then it is indicative of a code aperture having come into alignment with the path of light and in this event the processor is programmed to register the appropriate '1' or 'O' signal. If the comparison shows that the change in the reading has been occasioned by the trailing edge of a pulse no further action is taken at this time. This procedure continues for each of the angular locations of the code being read and is repeated for each of the reels. As each new part of the code is registered, the contents of the register are shifted to one side to accommodate the new registered part of the code. To determine which code relates to a given symbol there is provided within the microprocessor a pointer register associated with a memory block. The latter includes banks of symbol information corresponding to the symbols on the reels and the pointer register is controlled in accordance with the registered codes to relate the codes to the symbol information in the memory block. After decoding the resulting symbols are compared with one another to determine if the same symbols are aligned with one another in a "win" arrangement. In a modification each code may be defined by only one series of apertures such that only one LED and photo-transistor would be necessary for each reel. Provided the signals produced by the photo-transistor are synchronised to the speed of rotation of the reel, then each code would comprise, for example, five bits of information in the form of a signal where an aperture was provided at an angular location of the code, or no signal where no aperture was provided. In such a case it may be necessary to provide a master disc providing a series of pulses in accordance with rotation of the reel for synchronising with the pulses from the photo-transistor. As a start coding, an additional aperture may be provided of such a shape as to produce a pulse of different length from that produced by a code aperture. It is also envisaged that the number of photo-transistors required may be reduced by utilising only one photo-transistor for each series of code aperture locations, an optical fibre arrangement extending between the respective photo-transistor and the desired position aligned with the respective series of code aperture locations on each reel assembly. This arrange ment is possible as only one sensing means is operable at any on time. It is to be appreciated that a control system may be provided other than one including a microprocessor, with the information being stored in a shift register. The system is bi-directional. It will also be appreciated that a sensing arrangement other than one using photo-electric means may be utilised, for example a magnet and a Hall effect transducer where a screen for the magnetic flux is attached to the reel, or an ultrasonic arrangement comprising appropriate transmitters and receivers. It is further to be appreciated that the codes may be formed on other than the reel, for example on the toothed disc, with the sensing means being repositioned accordingly. In another modification the reels 10 or the toothed discs are formed of a material which allows transmission of light, for example a clear plastics. To define the codes, a masking arrangement is applied, for example by screen printing, and defines unmasked areas forming the transmission locations of the codes. Further, an arrangement may be utilised wherein the energy sources and the responsive components are provided at the same sides of the respective reels or toothed discs, the latter being arranged to reflect energy from the sources to the responsive components. The codes azure therefore defined by reflective areas. Various other modifications may be made without departing from the scope of the invention as defined in the appended claims.

Claims: Claims: 1. A reel mechanism for use in a gaming machine, said mechanism comprising a rotatable part, and sensing means having a source of energy as hereinbefore defined and means responsive to said energy, the rotatable part having means in the form of a code unique to each stop position thereof, characterised in that each code (26, 28) is arranged to permit serial transmission of energy from the source (14, 16) to the responsive means (18, 20) during travel of the rotatable part (10) in the path of energy from the source (14, 16), and means being provided for receiving electrical outputs from the responsive means (18, 20) to register the stop position of the rotatable part (10). 2. A reel mechanism for use in a gaming machine, said mechanism comprising a plurality of rotatable assemblies, a member of each assembly having a series of symbols arranged in an equi-spaced fashion around its axis of rotation and means for sensing the combination of symbols visible to the player, said sensing means comprising a source of energy as hereinbefore defined and means responsive to said energy, a part of each rotatable assembly having means in the form of a code unique to each stop position of the rotatable assembly, characterised in that each code (26, 28) is arranged to permit serial transmission of energy from the source (14, 16) to the responsive means (18, 20) during travel of said part (10) in the path of energy from the source (14, 16), and means being provided for receiving electrical outputs from the responsive means (18, 20) to register the angular position of the rotatable assembly. 3. A mechanism according to claim 2, characterised in that the or each energy source (14, 16) is provided at one side of the respective rotatable part (10) in alignment with the responsive means (18, 20) at the other side thereof, each code (26, 28) being arranged for alignment with the source (14, 16) and the responsive means (18, 20). 4. A mechanism according to claim 3, characterised in that each code (26, 28) comprises two series of locations (22, 24) through which energy can be transmitted, each series (22, 24) comprising transmission locations which are angularly spaced apart but at the same radial position, the angular position of both series (22, 24) corresponding to one another, and a predetermined number of angular positions being provided for the transmission locations in each code (26, 28), each series (22, 24) of transmission locations having a respective responsive means (18, 20) aligned therewith, the code (26, 28) being defined by the presence of a transmission location in a selected one of the series (22, 24) at each angular position. 5. A mechanism according to claim 4, characterised in that each code (26, 28) includes a coding (30) indicative of the start of the code for the respective stop position, the coding (30) comprising two transmission locations radially aligned at a further angular position at the radial positions of the respective series of transmission locations. 6. A mechanism according to claim 3, characterised in that each code comprises a series of locations through which energy can be transmitted angularly spaced apart at one radial position, a predetermined number of angular positions being provided for the transmission locations in each code, and the code being defined by the presence of a transmission location in a selected angular position, the means for receiving the electrical outputs from the responsive means being arranged to produce a signal at constant intervals of time, which signal differs in accordance with the presence or absence of a transmission location. 7. A mechanism according to claim 6, characterised in that each code includes a coding indicative of the start of the code for the respective stop position, the coding preferably comprising a transmission location shaped to produce a different output from the outputs of the other transmission location or locations of the code. 8. A mechanism according to claim 4 or 5, wherein each energy source is a light source and the responsive means comprises a single light sensitive device for each series of transmission locations, characterised in that an optical fibre arrangement extends between the respective light sensitive device and desired locations aligned with the respective series of transmission locations on the respective rotatable parts. 9. A mechanism according to claim 6 or 7, wherein each energy source is a light source and the responsive means comprises a single light sensitive device, characterised in that optical fibres are arranged between the latter and desired locations at the respective rotatable parts. 10. A mechanism according to any of the preceding claims, wherein the or each source of energy is a light source, characterised in that the or each rotatable part (10) is formed of a material which prevents transmission of light therethrough, the transmission locations being defined by apertures in each rotatable part (10). 11. A mechanism according to any of the preceding claims, wherein the or each source of energy is a light source, characterised in that the or each rotatable part is formed of a material which at least in part allows transmission of light therethrough, the transmission locations being defined by an arrangement on said part of each rotatable part which masks transmission of light. 12. A mechanism according to claim 2, characterised in that the or each energy source and responsive means is provided at the same side of the respective rotatable part. 13. A mechanism according to any of claims 1 to 7, characterised in that the or each energy source comprises a magnet arrangement with the or each responsive means in the form of a Hall effect transducer, a screen for the magnetic flux being provided on the or each rotatable part. 14. A mechanism according to any of claims 1 to 7, characterised in that the or each energy source comprises an ultrasonic transmitter with the or each responsive means comprising an ultrasonic receiver. 15. A mechanism according to any of the preceding claims, characterised in that a control system controls operation of the or each sensing means immediately before the respective rotatable part is due to be stopped and processes the information obtained from the sensed code so as to determine the angular position in which the rotatable part stops. 16. A mechanism according to claim 15, characterised in that the control system processes the information with a self-checking function such that the rotatable part is allowed to move to a further angular stop position if a sensed code is not acceptable.

Inventors: LUDLOW, ROY ALBERT GEORGE
Applicants: PANELWIRE CONTROLS LIMITED
Application year: 1980
Main classification: G07F17
IPC codes: G07F17