Game machine

Abstract: A game machine comprises hit flag counters which count up each hit request and count down on occurring each hit game. In said hit flag counters, if a hit can not be occurred in spite of a hit request, the hit request is stored up for the following games until the corresponding hit is obtained. A hit can be obtained only when the number of stored hit requests is not less than the number of inlet coins so that the payout rate of the game machine is exactly controlled to be constant in totality.

Description: BACKGROUND OF THE INVENTION The present invention relates to game machines, and more particularly to coin-operated game machines in which players can play a game by inserting coins (including tokens). As coin-operated game machines, slot machines and poker game machines are well-known. In a video-type poker game machine, for example, five cards are displayed on a CRT screen, those cards are changed at once when a start lever is actuated after a optional number of coins is inserted, and the card change is caused to stop automatically or upon pushing a stop button. A hit (prize-winning) is determined based on a combination of five cards displayed stationary on the CRT screen. The number of coins paid out for a hit depends on not only the rank of the obtained hit card combination but also on the number of inlet coins. Namely, the number of paid out coins becomes larger, the larger the number of inlet coins. Usually, the number of delivered coins is multiplied by the number of inlet coins for the same hit card combination. Recently, coin-operated game machines have microcomputers, with which the probability of obtaining a hit is so controlled as to keep a nearly constant pay out rate; for each game, a random value is sampled from a random number generator to compare it with a prize-winning or probability table in order to determine whether a present game is to be set as a hit game (prize-winning game) or not, or what kind of hit is to occur, and the microcomputer executes a game processing according to a hit game or lost game processing program. Thereby the probability of obtaining a hit can be kept nearly constant because the number of random values corresponding to hits can be predetermined in relation to the number of all random values to be generated from the random number generator. In this type of coin-operated game machine, if a sampled random value is found to correspond to a hit as a result of comparison with the hit probability table, a hit flag is generated so as to execute a hit game processing which makes it easier to obtain a hit. But it is not always possible to obtain a hit in spite of setting a hit flag. For example, in a game machine with hold buttons as disclosed in U.S.P. 4,700,948, in which a player can move any selective symbols a second time after the first stop of all symbols when the symbol combination displayed at the first stop did not correspond to a hit combination, if the combination induced by actuating the hold buttons does not fit with the hit symbol combination decided by the microcomputer, a hit can not occur. It can also be applied in case of a game machine with stop buttons as disclosed in U.S.P. 4,573,681 if stop buttons should be extremely ill-timed actuated. In this case, the hit flag is stored for the following games in order to keep the payout rate constant, so that the following games continue to be processed according to the hit game program until the corresponding hit is obtained. The coin-operated game machine, wherein not satisfied hit request are held effective in following games, has a problem that if a hit game is obtained in condition of a large number of inlet coins while a hit request is carried over from the prior game played in condition of a small number of inlet coins, the number of coins paid out at that time becomes too large due to its proportionality to the number of inlet coins so that the payout rate exceeds the predetermined rate. For example, if players intentionally repeat the game while inserting only one coin and actuating the hold buttons or stop buttons so as not to obtain a hit, and thereafter insert a larger number of coins choosing a time when a hit flag is considered to be set, a great number of coins would be delivered at high probability. Therefore the payout rate can not be exactly controlled. EP-A-142371 and EP-A-189256 describe prior art game machines according to the introductory part of claim 1. CH-A-54 24 84 describes similar prior art. OBJECTS OF THE INVENTION It is therefore an object of the present invention to provide a game machine whose payout rate can be kept constant irrespective of the number of inlet coins. This object is achieved by the features of claim 1. BRIEF DESCRIPTION OF THE DRAWINGS These and other objects and advantages of the invention will be easily understood by referring to the following description and accompanying drawings in which: Figure 1 is a block diagram showing circuit arrangements of an embodiment of a poker game machine according to the present invention; Figure 2 is a flowchart showing an example of a game process of the poker game machine of Fig. 1; Figure 3 is a perspective view showing a poker game machine embodying the present invention. DETAILED DESCRIPTION OF THE INVENTION Referring to Fig. 3 showing an outer appearance of a poker game machine embodying the present invention, a machine body 2 is provided at the front surface with a display window 3, through which a screen 4 of a CRT display 14 built in the machine body 2 can be observed. The CRT screen 4 displays five rows of cards arranged side by side thereon, under each card display position, there are provided respective corresponding hold buttons on the machine body surface. It may be possible to use a liquid crystal display panel, plasma display panel and the like as the display unit. Prior to starting games, coins are inserted into a coin inlet 6. When a start lever 7 is actuated, the CRT screen 4 begins to display five rows of cards moving vertically. Thereafter the cards stop at random automatically. If a combination of cards displayed stationary on the CRT screen 4 includes one of the hit combinations assigned in the poker game, a number of coins is paid out onto a coin saucer 8, the number being determined based on the rank of that hit card combination and also multiplied by the number of inlet coins. Referring now to Fig. 1, the poker game machine comprises a microcomputer 12 having a microprocessor unit ( hereinafter referred to as a MPU) 10, to which a start signal generator 13, the CRT display 14, the hold buttons 5, a coin detector 15, and a coin hopper 16 are connected. Responsive to the start lever actuation, the start signal generator 13 supplies a start signal to the MPU 10, which then controls the CRT 14 to display the cards moving on its screen 4 via a CRT controller 18 and a character memory 19. The hold buttons 5 are used to designate the cards to be kept back on a card-exchange. When any of the hold buttons 5 are pushed, corresponding hold signals are input into the MPU 10 via a hold signal input port 20, whereby designated cards are not moved and still displayed after the start lever 7 is actuated once more. This card-exchange operation can be carried out as a second round at every game without inserting additional coins, when no hit card combination would be obtained at the first round of the game. This card-exchange operation can be effected once for a game without sampling a new random number so that a player must again insert coins if he wants to play the next game. In case when a hit card combination can be obtained at the first round of a game, a player would not be allowed to execute the card-exchange, and must again insert coins for playing the next game. The coin detector 15 gives a signal every time when a coin is inserted into the coin inlet 6, and the signal is counted by a counter 21. The coin hopper 16 pays out a number of coins responsive to a signal from the MPU 10 when a hit is obtained, the number of paid out coins being determined on the basis of the rank of the obtained hit card combination as well as the count of the counter 21. A clock pulse generator 25 supplies clock pulses to the MPU 10 in a well-known manner, which executes a game processing at the timing of the clock pulses. Programs for the game processing are stored in a program memory, such as a ROM 26. A random value sampling circuit 28 samples a random number within a predetermined range at the first round of every game. The same random number can not be again sampled until all the other random numbers have been sampled, as long as the power source of the poker game machine is not turned off. A probability table 30 comprises a ROM having four memory areas each of which corresponds to a big, middle and small hit area, and a lost game area in a range of the random numbers. For example, when the random numbers to be sampled are in the range from "0" to "10000", the range from "0" to "50" is assigned to the big hit area, the range 51 to 250 to the middle hit area, the range "251" to "1500" to the small hit area, and the other random numbers to the lost game area. The big hit is assigned to such hit card combinations as "straight flash" which should occur at lowest probability; the middle hit is assigned to such hit card combinations as "flash" or "full house" which should occur at lower probability; the small hit is assigned to such hit card combinations as "one pair" or "two pairs" which should occur at relatively high probability. If a sampled random number is within the range corresponding to the big hit area, the MPU 10 gives a big hit flag to a big hit flag counter 32, which then counts up one count. Besides the big hit flag counter 32, a middle hit flag counter 33 and a small hit flag counter 34 are provided to count up the number of generated hit flags by area, whose counts are supplied to a judging portion 35. As will be described later in detail, if, at the start of a game, any of the flag counters 32, 33 and 34 are already set to "1" or more by the forgoing hit flags, the MPU 10 executes the hit game processing so that a hit card combination corresponding to one of the stored hit flags may occur even if the random number sampled at the present game is not within the hit areas, as long as the judging portion 35 detects that the number of inlet coins fulfills predetermined requirements. In other words, once a hit flag is generated, the hit flag is kept effective in following games until a corresponding hit is obtained. It is to be noted that there are two type of big, middle and small hits, first type of hits occur at one actuation of the start lever 7, while second type of hits are intended to occur after the card-exchange with pushing the hold buttons 5 for a second round. In case of a second type of hit, a card combination is displayed at the first round from which a player can be directly or indirectly deduce a hit card combination intended to be displayed by the microcomputer. Which type of hits should occur is selected according to the random number sampled at the first round. Of course, it may be possible to determine the type to be selected by using other random selecting means. If, in spite of a second type of hit being requested, no big hit should occur because of a wrong choice of hold buttons 5, the count of the corresponding hit counter would be kept unchanged, and carried over to the following games. The judging portion 35 gives a instruction to a display-character decision circuit 36, which then decides the characters to be displayed as a big, middle or small hit card combination, or a lost game card combination responsive to the instruction. The display-character decision circuit 36 designates via the MPU 10 the addresses in a character memory 19 corresponding to the decided characters. In case that the card combinations whose ranks are equal or higher than one pair of "JACK (11)" are predetermined as the hit card combinations, a card combination shown in Fig. 1 and 3 does not correspond a hit card combination. In this case, a player may push, for example, the first and second hold buttons on the right prior to again actuating the start lever 7 at the second round of a game (card-exchange) so that he can obtain three cards of "10", whereby only three cards on the left are caused to move and stop automatically. If the display-character decision circuit 36 decides to display a combination including "three cards of number 10", the player can obtain a hit, and hence a proper number of coins are paid out in the same manner as above. If, however, the pushed hold buttons do not yield an intended hit display, the game results in a lost game, and hence the hit flag is stored for the following game. The operation of the above described poker game machine will now be described with reference to the flowchart of Fig. 2. When a number of coins are inserted into the coin inlet 6, the inlet coin number "N" is registered in the counter 21. Upon actuating the start lever 7, the MPU 10 starts processing according to the game program in the program ROM 26, thereby to display five rows of cards moving vertically on the screen 4 of the CRT 14. As soon as the first round of a game is started, the random value sampling circuit 28 samples a random number, and to what area the sampled random number belongs is determined by referring to the probability table 30. If the random number belongs to any one of the hit areas, e.g the big hit area, the corresponding big hit flag counter 32 counts up by one count. In Fig. 2, "B", "M" and "S" indicate the count of the big, middle and small hit flag counter 32, 33 and 34, respectively. Thereafter, the judging portion 35 determines whether at least one hit flag counter 32, 33, 34 is set to "1" or more. Even if no hit flag is generated at the present game, if any one of the hit flag counters is still set to "1" or more, the count thereof is detected and compared with the count of the counter 21. Needless to say, in case that no forgoing hit flag is stored for the present game, and that a new hit flag is generated, the new hit flag would be effective. If the counts of all hit flag counters 32, 33 and 34 are "0", the lost game processing is executed according to the lost game processing program stored in the program memory 26, whereby the CRT controller 18 controls the CRT 14 to display a combination of cards corresponding to none of the hits stationary on the CRT screen 14 after the stop of the card movement. In this case, a player could not obtain a hit even though he would push some hold buttons 5 and actuate the start lever 7 on the card-exchange. It may be possible to store several lost game combination patterns in the display-character decision circuit 36. If any of the hit flag counters 32, 33 and 34, for example the big hit flag counter 32, is set to "1" or more, the judging portion 35 compares the count "1" of the big hit flag counter 32 with the number of coins "N" inserted at the beginning of a game. If the number N is larger than "1", the judging portion 35 gives a lost game processing instruction to the MPU 10, which then executes the lost game processing in the same manner as above. Also in this case, no hit could occur even though a card-exchange would be carried out after pushing the hold buttons 5. If the number of inlet coins "N" is "1" when the big hit flag counter 32 is set to "1", the judging portion 35 gives a big hit game processing instruction to the MPU 10 and the display-character decision circuit 36, whereby a combination of cards corresponding a big hit is displayed stationary on the CRT screen 4 at the first round or second round, and the coin hopper 16 pays out coins of a number depending on the rank of the big hit combination. At the end of the game, the count B of the big hit flag counter 32 is reduced by the number of inlet coins "N", namely the big hit flag counter 32 is reset to "0", and the counter 21 is also reset to "0". When the count B of the big hit flag counter 32 is "2", the counters 32 and 21 are reset to "0" if the number of inlet coins "N" is "2", but if the number of inlet coins "N" is "1", the big hit flag counter 32 counts down to "1" at the end of the game. The same game process as in case of a big hit flag is executed when the middle hit flag counter 33 or the small hit flag counter 34 is set to "1" or more by the middle or small hit flag, respectively. Namely, when the count "N" of the counter 21 is not more than the count "M" of the middle hit flag counter 33 or the count "S" of the small hit flag counter 34, the middle or small hit processing is executed, and the middle or small hit flag is kept effective until the corresponding hit card combination is obtained. In case of many hit flag counters 32, 33 and 34 being set to "1" or more, the priority is given to the big, middle and small hit in this order, but it may be possible to give a priority in the sequence of hit flag occurrence in stead of the kind of the hit. Or otherwise, when more than one hit flag counters are set to different counts and one of these hit flag counters has a count suitable for the number of inlet coins, the hit corresponding to the one hit flag counter would occur. For this hit game processing, the flow chart shown in Fig.2 should be so changed that the number "N" of inlet coins is compared with the count "M" of the middle hit flag counter when the number "N" is larger than the count "B" of the big hit flag counter and the number "N" is compared with the count "S" of the small hit flag counter when the number "N" is larger than the count "M". According to the above described game machine, a big or middle hit would not be occurred in case of a large number of coins, for example 20 pieces of coins, being inserted even after many games have been repeatedly played with a small number of coins, for example one piece of coin, while intentionally ill-selecting the hold buttons, because the big or middle hit flag counter 32 or 33 does not usually count up to "20". It would possibly occur that the small hit flag counter 34 counts up to "20" or more after the repetition of the above intentional lost game manipulation. In this case, a small hit would occur also when a game is played with 20 pieces of inlet coins. At this time, however, the count of the small hit flag counter 34 is reduced by the number of inlet coins so that a small hit would not occur in succession when playing a game again with 20 pieces of inlet coins. On the other hand, when a player continues to play a game by inserting one piece of coin after the count of the small hit flag counter 34 has reached "20", at least 20 times small hits can occur continuously. But the sum of the delivered coins is equal to the number of coins delivered at once on playing a game by inserting 20 pieces of coins. Consequently, the payout rate can be kept constant in any case. Although the above embodiment is directed to a poker game machine provided with the hold buttons, the present invention can be applicable not only to a poker game machine but also any kind of game machines, such as slot machines with stop buttons, in which coins are used to play a game and a hit request is given by a microcomputer.

Claims: A game machine having a microprocessor unit (10) for controlling a game process and means for generating a hit request (10,26,28,30) which effects hit game processing and a coin counter (21) for supplying a count representative of the number of coins inserted (6) at the beginning of a game, wherein the award (16) for a hit game depends on the number of inserted coins, and when a game results in a lost game in spite of a hit request being generated, said hit request is carried over for the following game, said game machine being characterized by means for counting the number of said hit requests (32,33,34); and judging means (35) connected to the coin counter (21) and the hit request counting means (32,33,34) which decides on whether hit game processing or lost game processing is effected in dependence on the values located in the counters (32,33,34,21) such that the number of hit requests necessary for a hit game processing is increased with the number of coins inserted. A game machine as defined in Claim 1, wherein said means for generating a hit request (10,26,28,30) comprises a random value sampling circuit for sampling a random value from a predetermined random value range, a probability table storing relationships between the random values and kinds of hits, said probability table being used to decide the kind of hit to be processed in accordance with a sampled random number; and said means for counting the number of said hit requests (32,33,34) comprises a plurality of hit flag counters (32,33,34) each of which counts up each kind of said hit request. A game machine as defined in Claim 2, wherein as said kind of hits, there is a big hit for which a largest number of coins are delivered, a middle hit for which a larger number of coins are delivered, and a small hit for which a small number of coins are delivered. A game machine as defined in Claim 2, wherein as long as at least one of said hit flag counters (32,33,34) is set to "1" or more, said judging means (35) compares the count of said at least one hit flag counter with the count of said coin counter (21), and instructs to execute a hit of a kind corresponding to one of such hit flag counters (32,33,34) as having a count equal or more than "1" only when the count of this hit flag counter is not less than the count of said coin counter (21). A game machine as defined in Claim 4, wherein when the counts of a plurality of said hit flag counters (32,33,34) are equal or more than "1", one of corresponding hits is allowed to occur according to a predetermined priority. A game machine as defined in one of Claims 1 to 5, wherein said game machine further comprises hold buttons (5) for keeping any selective character being displayed within a display window (3) of said game machine on exchanging the display-character, said display-character exchange can be carried out as a second round of a game without inserting additional coins, and the same instruction from said judging means (35) is used for the second round as for the first round. A game machine as defined in Claim 6, wherein said hit requests include two types of hit requests, one for hits to be obtained at the first round, the other for hits to be obtained at the second round.

Inventors: HARADA MASAMICHI, HARADA, MASAMICHI
Applicants: UNIVERSAL KK, KABUSHIKI KAISHA UNIVERSAL
Application year: 1989
Main classification: G07F17
IPC codes: A63F13, A63F5, G07F17