Slot machine

Abstract: Whether or not a hit is given to a game is determined before symbol trains stop moving, or preferably when a start lever is manipulated for starting the motion of the symbol trains. For a game allowed to have a hit, the motion speed of symbol trains is switched from a high speed to a low speed, or the speed is set at a low speed from the beginning. For a game not allowed to have a hit, the symbol trains move at a high speed from the beginning. From the difference between motion speeds, a player can be given beforehand suggestion as to whether the game has been allowed to have a hit.

Description: SLOT MACHINE The present invention relates to a slot machine capable of visually suggesting that a game now being played has been allowed to have a hit (i.e. a win). One type of slot machine has a plurality of, e.g. three to five, reels with a plurality of symbol marks disposed on each outer periphery thereof. These reels start rotating at a time when a game starts. After the rotation of each reel reaches a constant speed, a stop control is allowed to be executed. This stop control for each reel rotating at a constant speed can be conducted upon manual actuation of a stop button (a manual stop type machine) or by the operation of an automatic stop device (an automatic stop type machine). When all the reels have stopped, the presence/absence of a hit is determined from a combination of symbol marks of the respective reels on one or more winning lines the effective number of which is determined in accordance with the number of inserted coins (including tokens). Coins corresponding in number to the hit rank are paid out. Slot machines of the type in which the player stops the reels have been proposed which can offer on a random or pseudo-random basis a "feature" or "bonus" game in which the reels are rotated slowly to give the player a better chance of winning. Such a slow-speed game can also be made available after a particular combination has been obtained in a previous game. Such slot machines are disclosed in GB-A-2119991, GB-A-2100492, GB-A-2119145 and DE-2814183. The aim is to increase the attractiveness of the game to the player and retain his interest by increasing his influence on the game. Other slot machines have been proposed in which a player's interest can be maintained by giving the appearance of a malfunction which is advantageous to the player, e.g. in GB-A-2152263, or by provision of a special nudge feture e.g. in GB-A-2062922 or by indicating to the player when to operate the controls e.g. in EP-A-91832. With one type of conventional slot machine, at a certain time during the period from inserting coins to starting the reel stop control, it is judged by using random numbers whether or not the game is allowed to have a hit, and if a hit is allowed, its rank is also determined. In accordance with this judgement, the reel stop control is executed. In a slot machine of the manual stop type, even a game allowed to make a hit may result in a lost game because the reel stop positions are restricted and the player may operate the controls badly so that a hit cannot be awarded. In this case, the hit designation can be carried over to the next game. Players in general wish to have a big hit with a large pay-out or a bonus game having a high hit probability. These special hits cause many coins to be paid out. In order to maintain a stable payout rate, the probability of occurrence of special hits is controlled by using random numbers as described before to inhibit concentrated occurrences of special hits. With a limited low probability of occurrence of special hits, players tend to have an impression that a special hit suddenly occurs after a number of repeated games. Most of the games therefore arouse player's interest only after the reels actually stop, with an uninteresting wait during the period from starting rotating reels to stopping them. This is one of the major reasons for games being monotonous and dull. The same problem also arises with slot machines of the type in which symbol marks are displayed on a CRT instead of reels. It is therefore an object of the present invention to provide a slot machine capable of visually suggesting that the game now being played has been allowed to make a hit. In accordance with the present invention, there is provided slot machine having a display for displaying a plurality of moving symbol series during playing a game, comprising: determining means for determining before said symbol series are stopped the rank of payment intended for the game; stop control means for controlling the stop position of the moving symbol series in accordance with the rank of payout determined by the determining means; speed setting means for changing the moving speed of at least one of said symbol series in accordance with the rank of payout determined by said determining means to visually indicate the rank of payout intended for the game. The motion speed difference may be achieved by moving symbol series at a low speed from the beginning, or by changing the speed in the midst of such motion of symbol series. For a slot machine of a manual stop type, the stop operation by an operator can be advantageously carried out at a proper timing because the motion of symbol series is slow. On the contrary, the motion speed for a game allowed to have a hit may be made faster than that for a game not allowed to have a hit. According to the present invention, whether a game is allowed to have a hit can be notified beforehand while symbol series are being moved. A monotonous progress of a game can be eliminated thereby giving much fun to a player. Such prior suggestion preferably is given to a game allowed to have a special hit with a large award. However, it is not limited thereto, but such prior suggestion may be given to a game allowed to have a hit even with a small hit. The invention is applicable to both manual and automatic stop machines and also to both machines with the symbol series on moving reels and with the series displayed on a CRT. The invention will be further described by way of non-limitative example with reference to the accompanying drawings, in which: Fig.1 is a perspective view showing an embodiment of the machine according to the present invention; Fig.2 is a schematic diagram showing the electric circuit arrangement of the slot machine shown in Fig.1; Fig.3 is a functional block diagram of the system controller shown in Fig.2; and Figs.4 to 6 are timing charts showing the relationships between drive pulses and pulse motor revolution rates. Referring now to Fig.1 showing a perspective view of a slot machine according to the present invention, the slot machine 2 has a front door 2a capable of being open and closed. The front door 2a has stop buttons 3 to 5, start lever 6 and coin inlet 7, respectively mounted thereon. A front panel 8 is fitted in the front door 2a above the stop buttons 3 to 5. First to third reels 9 to 11 are rotatably mounted at the back of the front panel 9. On the outer periphery of each reel 9 to 11, various symbols such as "lemon", "7", and "bell" are drawn and can be viewed from three windows 12 to 14 formed in the front panel 8. A plurality of winning lines 16 are drawn over the windows 12 to 14 which are made effective in accordance with the number of inserted coins. Upon actuation of the start lever 6 after coins are inserted into the coin inlet 7, the reels 9 to 11 start rotating at a time. After the rotation of the reels 9 to 11 reach a constant revolution rate, the stop buttons 3 to 5 are allowed to be actuated by a player. After the stop buttons 3 to 5 are operated at desired timings, the stop control starts and the reels 9 to 11 stop, and symbols are aligned on an effective winning line, the symbols being determined in accordance with the presence/absence of a predetermined hit and its rank. If a combination of three symbols stopping at the effective winning line is a hit symbol combination, coins corresponding in number to the hit rank are paid out onto a coin saucer 17. If the stop buttons 3 to 5 are not operated within a predetermined period, each reel 9 to 11 is stopped by a known automatic stop mechanism. Reference numeral 18 represents a display unit for displaying the number of coins to be paid out. Referring to Fig.2 showing the electric circuits of the slot machine 2, pulse motors 20 to 22 for driving the respective reels 9 to 11 are connected via corresponding drivers 23 to 25 to a system controller 26. Photosensors 27 to 29 detect light interrupting pieces 30 to 32 mounted on the reels 9 to 11 so that the reels 9 to 11 at the reference positions can be detected. Connected to the system controller 26 are stop switches 3a to 5a for outputting stop signals upon actuation of the stop buttons 3 to 5, a start switch 6a to be operated by the start lever 6, a coin insertion sensor 35 for detecting a coin inserted from the coin inlet 7, and a coin payout unit 37 which is driven by a driver 36. The start switch 6a outputs a start signal when the start lever 6 is manipulated. The coin insertion sensor 35 outputs a random number generation signal when a coin is detected with the coin insertion sensor 35. Referring to Fig.3 illustrating the function of the system controller 26, a random number generator 40 is started operating upon insertion of a coin, and generates a random number from "1" to "3000". The random number generator 40 is connected to a sampling circuit 41 which starts sampling upon reception of the start signal. The sampling circuit 41 is preferably constructed such that it does not sample the same random number again while playing games 3000 times. The sampling circuit 41 is connected to a symbol determining circuit 42 which refers to a symbol table 43, using the sampled number as a key to thereby determine a symbol combination and three symbols thereof. The data of each determined symbol is sent to a stop position determining circuit 44 to which connected are the stop switches 3a to 5a and a motor controller 45 for controlling the pulse motors 20 to 22. The stop position determining circuit 44 receives the stop signals from the stop switches 3a to 5a and controls to stop the pulse motors 20 to 22. In this stop control, by referring to the revolution position signals of the reels 9 to 11 supplied from a search circuit 47 to be described later, the stop position determining circuit 44 controls the motor controller 45 so that the symbols determined by the symbol determining circuit 42 are caused to stop on an effective winning line 16. Note that if the timings of actuating the stop buttons 3 to 5 and of actually stopping the reels 9 to 11 are different considerably, players feel the stopping manner unnatural. For this reason, a shift control (e.g., by the amount corresponding to a plurality of symbols) which gives natural feelings to players is carried out in order to stop the symbols on a winning line. Consequently, a symbol combination determined by the symbol determining circuit 24 might not necessarily be established. In such a case, a stop control for the hit combination is carried over to the next game. Connected to the motor control circuit 45 are the start switch 6a, a drive pulse timing table 46, the search circuit 47, and a payout controller 49. The drive pulse timing table 46 stores the timing data for outputting drive pulses from the motor control circuit 45 to the pulse motors 20 to 22. If symbol "7" signals are outputted for all reels from the stop position determining circuit 44 to the motor control circuit 45, the motor control circuit 45 decelerates the pulse motors 20 to 22 rotating at a constant speed after a lapse of a predetermined time. For instance, as shown in Fig.4, the stop position determining circuit 44 sends drive pulses to the pulse motors 20 to 22 such that the constant revolution rate or speed of N₁ rpm is lowered from time T₄, and at time T₅ it reaches a constant revolution rate of N₂ rpm. If the symbol combination "777" has been carried over from the previous game, as shown in Fig.5 the circuit 44 sends drive pulses to the pulse motors 20 to 22 such that the motors are accelerated not to the constant revolution rate of N₁ rpm, but they are driven at the constant revolution rate of N₂ rpm. If a symbol combination other than the symbol combination "777" is to be established, as shown in Fig.6 drive pulses are sent to the pulse motors 20 to 22 such that the motors are driven at the constant revolution rate of N₁ rpm. As seen from Fig.5, the revolution rate of each pulse motor is controlled by changing the period of drive pulses. The search circuit 47 checks the positions of symbols on the rotating reels 9 to 11 in accordance with the numbers of drive pulses counted from the time when the photosensors 27 to 29 detect the reference positions. The obtained revolution position signals are sent to the stop position determining circuit 44. When it is found that the symbol combination has a hit after all the pulse motors 20 to 22 have stopped, the payout controller 49 causes the driver 36 and coin payout unit 37 to pay out coins corresponding in number to the hit rank. Next, the operation of the embodiment will be described with reference to Figs.4 to 6. When a coin is inserted into the coin inlet 7 at time T₀ shown in Fig.4, the coin insertion sensor 35 sends a random number generation signal to the random number generator 40 which then starts operating. When the start lever 6 is manipulated at time T₁, the start signal is sent to the sampling circuit 41 and motor controller 45. The sampling circuit 41 samples a random number from the random number generator 40 and sends it to the symbol determining circuit 42. If the sampled random number falls within the range from "1" to "10", it means a hit symbol combination "777" having a large award. The symbol determining circuit 42 refers to the symbol table 43 to determine the symbols for the reels 9 to 11 as "7", and sends the symbol signals representative of the symbol "7" to the motor controller 45. The motor controller 45 starts the pulse motors 20 to 22 at time T₁ in accordance with the data in the drive pulse timing table 46, and to gradually raise their speed. After the pulse motors 20 to 22 reach the constant revolution rate N₁ rpm at time T₃, the stop buttons 3 to 5 are allowed to be actuated. Deceleration starts at time T₄, and at time T₅ the pulse motors are driven at a low constant revolution rate of N₂ rpm. Upon actuation of the stop button during the period from time T₃ to T₈, the corresponding pulse motor starts being decelerated to thereby make the predetermined symbol stop on the winning line. If the stop buttons are not actuated during this period, the pulse motors 20 to 22 start undergoing the stop control after time T₈ as indicated by the broken line. For instance, upon actuation of the stop button 3 during the period from time T₃ to T₄, a stop position signal is outputted from the stop position determining circuit 44 to the motor controller 45. Referring to the revolution position signal from the search circuit 47, the motor controller 45 executes a stop control for the pulse motor 20 to stop the symbol "7" of the first reel 9 on the winning line 16. The remaining two pulse motors 21 and 22 are decelerated from time T₄, and rotates the constant revolution rate of N₂ rpm reaches from time T₅. If the stop button 4 is actuated before or after time T₅ for example, the stop position determining circuit 44 and motor controller 45 execute a stop control for the pulse motor 21 to stop the symbol "7" of the second reel on the winning line 16. If the stop button 5 is actuated at time T₆, the motor controller 45 starts decelerating the pulse motor 22 rotating at the constant revolution rate of N₂ rpm so as to stop it at time T₇. After all the reels stop, the symbols on the reels 9 to 11 on the effective winning line 16 become all "7" to thereby establish a special hit symbol combination "777". After all the reels 9 to 11 stop, in accordance with the established hit symbol combination rank, the payout controller 45 sends a payout signal to the payout unit 37 to pay out a predetermined number of coins. It is obvious that the order of actuating the three stop buttons is arbitrary. With a slot machine of the manual stop type, even if a hit of "777" has been allowed, this "777" might not be established in some cases by using only the reel stop position shift control, depending upon the timings of actuating the stop buttons 3 to 5 and the time T₈ when the automatic stop starts. In such a case, the hit is carried over to the next game whereat the pulse motors 20 to 22 are driven at the low constant revolution rate of N₂ rpm as shown in Fig.5. Specifically, the motor controller 45 sends drive pulses as shown in Fig.5 from time T₁ to the pulse motors 20 to 22 to rotate them. At time T₂ the pulse motors 20 to 22 reach the low revolution rate of N₂ rpm, and thereafter the stop buttons are allowed to be actuated. Upon actuation of the stop buttons, the motor controller 45 outputs stop position signals to stop the pulse motors 20 to 22 for stopping the symbols "7" on the reels 9 to 11 on the effective winning line 16. In this case also, the same procedure is repeated if the symbol combination "777" is not actually realized. If the presence/absence of a hit is determined prior to the rotation of the reels, the constant revolution rate of N₂ rpm shown in Fig.5 may be used for the game allowed with a hit, instead of changing the reel speed in two steps as shown in Fig.4. If the random number sampled at time T₁ falls within the range from "11" to "3000", the symbol determining circuit 42 refers to the symbol table 43 to determine a symbol combination. The symbol determining circuit 42 supplies the stop position determining circuit 44 with the symbol signals corresponding to the determined symbol combination. The motor controller 45 supplied with the symbol signals from the stop position determining circuit 44 sends drive pulses as shown in Fig.6 to the pulse motors 20 to 22 to thereby drive them at the high revolution rate of N₁ rpm. During time T₃ to T₇, the stop buttons 3 to 6 are allowed to be actuated. For instance, if the stop button is actuated at time T₆, the corresponding pulse motor is controlled to stop the predetermined symbol on the winning line. If the stop buttons are not actuated, the pulse motors are decelerated from time T₇ and stop at time T₉ as indicated by the broken line. In the above-described embodiment, for the game having been allowed to have a special hit with a large award, the pulse motors are driven at the low revolution rate after the lapse of a predetermined time. Instead, after the stop button is first actuated, the remaining two reels may be switched to the low revolution rate. With such an arrangement, games can be given a feeling least expected. Furthermore, in the above embodiment, the reels 9 to 11 are driven at the low revolution rate so that stop buttons can be advantageously actuated at suitable timings so as to obtain the symbol "7". However, the reels may be rotated at the high revolution rate for the game allowed to have a hit, without giving such an advantage. Furthermore, for a hit other than "777" with a smaller award, the rotation speed of reels may be changed. The present invention is applicable to slot machines not only of the manual stop type but also of the automatic stop type lacking stop buttons. Further, in the above embodiment, although a train of symbols are carried on the outer periphery of a reel, this invention is applicable to a video type slot machine with symbol trains being displayed on a display unit. Coins may be paid out each time a hit is made, or the number of coins obtained may be added to a credit counter to display the added result each time a hit is made. In the latter case, without inserting a coin, the game can be started upon manipulation of the start lever 6 and the contents of the credit counter is reduced correspondingly. A coin number designation button may preferably be provided so as to designate the number of coins to be inserted. While the invention has been described in detail above with reference to a preferred embodiment, various changes and modifications within the scope of the invention will be apparent to people of working skill in this technological field. Thus, the invention should be considered as limited only by the scope of the appended claims.

Claims: A slot machine having a display (9-14) for displaying a plurality of moving symbol series (9-11) during playing a game, comprising: determining means (40,41) for determining before said symbol series (9-11) are stopped the rank of payment intended for the game stop; control means (44) for controlling the stop position of the moving symbol series (9-11) in accordance with the rank of payout determined by the determining means (40,41); speed setting means (45,46) for changing the moving speed of at least one of said symbol series (9-11) in accordance with the rank of payout determined by said determining means to visually indicate the rank of payout intended for the game. A slot machine according to claim 1, further comprising stop means (3,4,5) for stopping the motion of each of said symbol series (9-11). A slot machine according to claim 1 or 2, wherein, for a game designated as a prize-winning game, each of said symbol series (9-11) moves at a first speed initially during said motion, and moves at a second speed lower than said first speed after a predetermined time has lapsed since the beginning of said motion of each of said symbol series (9-11). A slot machine according to claim 3, wherein, if in a game designated as a prize-winning game the symbol series (9-11) are stopped at a lost game position, each of said symbol series (9-11) moves at said second speed in the next game from the beginning thereof. A slot machine according to claim 1 or 2, wherein, in a game designated as a prize-winning game, each of said symbol series (9-11) moves at a first speed initially during said motion, and, after one of said symbol series stops, the remaining symbol series move at a second speed lower than said first speed. A slot machine according to claim 1 or 2, wherein, in a game designated as a prize-winning game, each of said symbol series moves at a first speed, and, in a game which is not designated as a prize-winning game, moves at a second speed higher than said first speed. A slot machine according to any one of the preceding claims, wherein said speed setting means (45,46) changes said speed only for a prize with a large award to a player. A slot machine according to any one of the preceding claims, wherein said symbol series (9-11) is carried on the outer periphery of a reel which is rotated by a pulse motor (20-22).

Inventors: OKADA KAZUO, OKADA, KAZUO
Applicants: UNIVERSAL KK, KABUSHIKI KAISHA UNIVERSAL
Application year: 1990
Main classification: G07F17
IPC codes: G07F17, A63F5