Gaming machine and game system

A gaming machine includes an operation unit that is operated by a player, a game mode switching unit that switches a game mode, and a game control unit that controls a game based on the game mode. The game mode switching unit switches, based on the operation via the operation unit, a game mode between an insured mode where a compensation function works to compensate for a loss and an uninsured mode where the compensation function does not work.

CROSS REFERENCE TO RELATED APPLICATION

This application is based upon and claims the benefit of priority from the prior Japanese Patent Applications No. 2004-358153, filed on Dec. 10, 2004, No. 2004-358206, filed on Dec. 10, 2004, No. 2004-361553, filed on Dec. 14, 2004, No. 2004-369248, filed on Dec. 21, 2004, and No. 2005-213181, filed on Jul. 22, 2005, the entire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a gaming machine such as a slot machine, a pachi-slot machine, and a pachinko machine, and also relates to a game system including a gaming machine and a server that is connected in communication with the gaming machine.

2. Description of Related Art

In a gaming machine such as a slot machine and a card game machine, when a game medium such as a coin is inserted into the gaming machine to start a game, an internal lottery is performed, and the game result is displayed based on the result of that internal lottery. For example, in a slot machine, a symbol determined by the internal lottery is stopped and displayed on a reel, and in a card game machine, a card of specified type determined by the internal lottery is displayed. Then, based on the game result, a predetermined number of game media are paid out.

In such a gaming machine, a probability of offering an advantageous game result to a player, e.g., the probability of a win on a pay line, is set to a predetermined value. In this case, the winning probability converges at a predetermined value, for example, a payout rate is 80%, after quite a few games are performed. This causes problems in which many game media are obtained even though few game media are spent, and in which only a few game media are obtained even though a great number of game media are spent. Therefore, gambling orientation is increased to add amusingness to games, whereas a player loses expectations for games when it is difficult to obtain the advantageous game result, which can cause a game shop having such a gaming machine to lose customers.

In order to prevent a player from losing expectations for games, various techniques are proposed. For example, there is a technique to automatically conduct a payback system in which game media such as inserted coins are partially preserved to pay back afterward (see JP-A-2003-117070). According to the payback system, when the amount of lost credits equal to or more than an upper limit, the preserved game media are offered to a player. Furthermore, there is a technique in which an additional coin insertion slot for insurance is provided, and three insurance coins are inserted thereto to apply an insurance function. When a predetermined number of coins are inserted into a gaming machine during a game, insurance coins are paid out (see JP-A-4-244178).

SUMMARY OF THE INVENTION

However, according to the former of the two techniques, regardless of player's intention, inserted game media are partially reserved for payback, and therefore, the player can expect to have a payback. However, since relatively many game media are required for payback, some players desire to play games without utilizing the payback system. The payback system functions without consideration for such the player's intention, which can reduce the player's willingness for games. According to the latter's technique, once the insurance function starts to work, it is continuously working for a predetermined time period regardless of the player's intention. However, it is sometimes advantageous without the insurance function, depending on game conditions. Operating the insurance function even in such a case, without consideration for the player's intention, can also reduce the player's willingness for games.

It is an object of the present invention to provide a gaming machine and a game system, in which a compensation function is provided that compensates for a loss due to games to prevent a reduction in player's expectations for games, and the compensation function is stopped in accordance with player's intention to increase player's satisfaction.

According to an aspect of the invention, there is provided a gaming machine including: a receiving unit that receives a game medium; an exchange unit that exchanges the game medium received by the receiving unit to a game value to be used in a game; a payout unit that pays out a predetermined value of the game medium based on the game value exchanged by the exchange unit and on a game result; an operation unit that can be operated by a player; a game mode switching unit that switches, based on the operation via the operation unit, a game mode between an insured mode where a compensation function works to compensate for a loss and an uninsured mode where the compensation function does not work; and a game control unit that controls a game based on the game mode.

In the aspect, based on the operation of the operation unit by a player, the game mode is switched between the insured mode where the compensation function works and the uninsured mode where the compensation function does not work. In other words, a player can select whether or not to apply the compensation function by his/her intention. Thus, player's satisfaction can be increased.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, preferred embodiments of the invention will be described with reference to the drawings.

First, with reference toFIG. 1, the configuration of a slot machine1of a first embodiment of a gaming machine according to the invention will be described.

The slot machine1of the embodiment has a cabinet2. A sub display3is placed on the front upper part of the cabinet2, and a main display4is placed at the center of the front of the cabinet2. The sub display3and the main display4are general-purpose liquid crystal displays.

A pair of speakers5L and5R is placed on the right and left of the sub display3, which output predetermined BGM, sounds, sound effects, or the like, based on the game mode of the slot machine1. Below the main display4, a control panel6is disposed as extended toward the front. Provided on the control panel6are a control panel8arranged with various buttons, a coin insertion slot9and a bill insertion slot10into which coins and bills are respectively inserted as a game medium.

On the sub display3, displayed are information on games such as game methods, types of winning combinations and payout numbers thereof, and various effects for games.

On the main display4, the amount of credits currently owned and various effects image are displayed, while five video reels21,22,23,24and25are displayed substantially at the center thereof. The slot machine1is a so-called video slot machine. On each of the video reels21to25, various symbols described below are variably displayed as scrolled from above to below for a predetermined time period, and stopped in a predetermined combination. A slot game performed in the slot machine1is categorized into two of a base game and a bonus game, both of which are performed through the video reels21to25.

On the lower left corner of the main display4, an insurance indicator11and an owned credits indicator12are provided. The insurance indicator11, which is displayed only when the game mode is in an insured mode described below, displays a bar graph (seeFIG. 4). The bar graph represents the amount of lost credits from the time point when the insured mode is set to the present and the required amount of lost credits for compensation. Here, the amount of lost credits is derived by subtracting the amount of credits paid out based on the game result from the amount of bet credits. On the owned credits indicator12, the amount of owned credits which are currently owned by a player is displayed. In the embodiment, one coin corresponds to one credit.

As shown inFIG. 2, each of the video reels21to25has three stop areas, and various symbols are stopped in each of the stop areas. More specifically, the video reel21has stop areas211,212and213, the video reel22has stop areas221,222and223, the video reel23has stop areas231,232and233, the video reel24has stop areas241,242, and243, and the video reel25has stop areas251,252and253. In each of the stop areas211to213,221to223,231to233,241to243, and251to253, a predetermined symbol is stopped and displayed based on an internal lottery described below.

In the embodiment, there are twenty pay lines each consisted of five stop areas among the stop areas211to213,221to223,231to233,241to243, and251to253. The pay lines are selectively activated based on the press of a BET 1 PER LINE button33, a BET 3 PER LINE button34, and a BET 5 PER LINE button35, which are described below. When symbols are stopped after variably displayed, certain symbols are arranged in a certain form on an activated pay line (hereinafter called an ‘activated line’) so that a payout is given.

On the control panel8, various buttons are placed as shown inFIG. 3. More specifically, on the upper part of the control panel8, a COLLECT button31, a GAME RULES button32, and an INSURE ON/OFF button13are arranged sequentially from the left, in the middle part, a BET 1 PER LINE-button33, a BET 3 PER LINE button34, a BET 5 PER LINE button35, and a WIN/START FEATURE-button36are arranged sequentially from the left, and on the lower part, a PLAY 1 LINE button37, a PLAY 5 LINES button38, a PLAY 20 LINES button39, and a GAMBLE/RESERVE button40are arranged sequentially from the left.

The COLLECT button31is a button for ending a game and for obtaining the payout of coins equivalent to the owned credits. The coins are paid out from a coin payout opening15to a coin tray16through a hopper71(seeFIG. 6) disposed inside the slot machine1. When the COLLECT button31is pressed, lost credit data used in the insured mode is initialized.

The GAME RULES button32is a button to be pressed when how the game should be operated is not clear to a player. When the GAME RULES button32is pressed, help information is displayed on the sub display3and/or the main display4.

The INSURE ON/OFF button13is a button for switching the game, mode. The game mode in the slot machine1is categorized into two of the insured mode and an uninsured mode. Every time when the INSURE ON/OFF button13is pressed, the game mode is switched between the insured mode and the uninsured mode. In the insured mode, a compensation function works to compensate for a loss. In the embodiment, the compensation function works, when the amount of lost credits is equal to or more than an upper limit, to pay out a predetermined number of credits for compensation of collecting one credit as an insurance fee. When the game mode is in the insured mode, the insurance indicator11is displayed on the main display4.

The BET 1 PER LINE button33, the BET 3 PER LINE button34, and the BET 5 PER LINE button35are buttons for increasing the bet number on each activated line by one, three, and five, respectively. The WIN START FEATURE button36is a button for starting a bonus game or for adding the payout obtained in the bonus game to owned credits. The PLAY 1 LINE button37, the PLAY 5 LINES button38, and the PLAY 20 LINES button39are buttons to starting a game as the number of activated lines is 1, 5, and 20, respectively.

The GAMBLE RESERVE button40is a button to be pressed when a player leaves a seat or pressed for playing a so-called double down game after the bonus game is ended. The double down game is a game with the credits obtained in the bonus game, the detail of which is omitted herein.

A switch is disposed inside each of the buttons13and31to40of the control panel8. When a button is pressed, a switch corresponding to the button outputs a switch signal to a CPU50seeFIG. 6). More specifically, a COLLECT switch45is placed in the COLLECT button31, a GAME RULES switch46is placed in the GAME RULES button32, an INSURE ON/OFF switch76is placed in the INSURE ON/OFF button13, a 1-BET switch57, a 3-BET switch58, and a 5-BET switch59are placed in the BET 1 PER LINE button33, the BET 3 PER LINE button34, and the BET 5 PER LINE button35, respectively, a WIN START switch47is placed in the WIN START FEATURE button36, a 1-LINE switch60is placed in the PLAY 1 LINE button37, a 5-LINES switch61is placed in the PLAY 5 LINE button38, a 20-LINES switch62is placed in the PLAY 20 LINES button39, a GAMBLE RESERVE switch48is placed in the GAMBLE RESERVE button40.

A coin sensor49is disposed adjacent to the coin insertion slot9in the cabinet2to detect coins inserted through the coin insertion slot9. A coin detection signal is outputted from the coin sensor49to the CPU50(seeFIG. 6), and the credits equivalent to the inserted coins are added to the owned credits. Similarly, a bill sensor67is disposed adjacent to the bill insertion slot10in the cabinet2to detect the types and amount of bills inserted through the bill insertion slot10. A bill detection signal is outputted from the bill sensor67to the CPU50(seeFIG. 6), and the credits equivalent to the inserted bills are added to the owned credits.

On the front lower part of the cabinet2, the coin payout opening15and the coin tray16which holds coins ejected from the coin payout opening15are disposed. In a passage to the coin payout opening15in the cabinet2, a hopper71, which ejects coins one by one from the coin payout opening15, and a coin sensor73, which detects coins paid out from the coin payout opening15and outputs a coin detection signal to a payout completion signal circuit72, are disposed (seeFIG. 6).

Next, with reference toFIG. 4, the insurance indicator11displayed on the main display4will be described.

As shown inFIG. 4, the insurance indicator11includes a gage part90, an initial value display part91, an upper limit display part92, and a lost amount display part93. In the gage part90, a gage area89indicates the amount of lost credits by the ratio with respect to the upper limit which is 2000 credits in the embodiment. The initial value display part91indicates, on the right below the gage part90, ‘0’ as the initial value of lost credits. The upper limit display part92displays ‘2000’ as the upper limit. The lost amount display part93indicates, at the upper right end of the gage area89, current amount of lost credits by arabic numerals.

When a player bets, the gage area89extends its area rightward, and the numeric of the lost amount display part93is increased by the number of lost credits which is, for example, when a game is played for five activated lines and three bets per line, sixteen credits in total including one credit for the insurance fee. Then, at the end of a game, when the amount of lost credits is equal to or more than the upper limit of 2000 credits, a predetermined number of credits, e.g., 100 credits, are paid out. Here, a game is a series of performances including steps of betting, variably displaying and stopping symbols, a payout, a bonus game process, and the like.

When a player obtains a predetermined number of credits which are paid out because of a win, the gage area89decreases its area leftward, and the numeric of the lost amount display part93is reduced by the number of credits paid out. Here, when the amount of lost credits is equal to or below zero, the lost amount display part93always displays ‘0’, which is the initial value of lost credits as described above, while the area of the gage area89is gone.

Next, with reference toFIG. 5, symbol columns variably displayed on the video reels21to25will be described.

When any one of the PLAY buttons37to39is pressed to start a game, symbol columns included in a first reel band111, a second reel band112, a third reel band113, a fourth reel band114, and a fifth reel band115are scrolled and displayed from above to below on the video reels21,22,23,24and25, respectively. After a predetermined time period has elapsed, three symbols are stopped on each of the video reels21to25. Dot data for creating images of the symbols included in the reel bands111to115is stored in image ROM82(seeFIG. 7).

The symbol columns included in the reel bands111to115, have symbol arrangements, which are different from each other. Each of the symbol columns has a combination of thirteen symbols of ‘LOBSTER’, ‘SHARK’, ‘FISH’, ‘PUNK’, ‘OCTOPUS’, ‘CRAB’, ‘WORM’, ‘A’, ‘K’, ‘Q’, ‘J’, ‘WILD’, and ‘SARDINE’. The symbols ‘LOBSTER’, ‘SHARK’, ‘FISH’, ‘PUNK’, ‘OCTOPUS’, ‘CRAB’, ‘WORM’, and ‘SARDINE’ depict symbols of lobster, shark, fish, a person with a guitar, octopus, crab, worm, and sardine, respectively. The symbols ‘A’, ‘K’, ‘Q’, ‘J’, and ‘WILD’ depict alphabets corresponding thereto.

Stopping a predetermined number of the same symbols of ‘LOBSTER’, ‘SHARK’, ‘FISH’, ‘PUNK’, ‘OCTOPUS’, ‘CRAB’, ‘WORM’, ‘A’, ‘K’, ‘Q’, and ‘J’, respectively, on an activated line from the left end results in a predetermined payout number (seeFIG. 9). The symbol ‘SARDINE’ is a so-called scatter symbol so that stopping two or more of the symbol ‘SARDINE’ in total in any of the stop areas of the video reels21to25, not limited to the activated line, results in a predetermined payout number. The symbol ‘SARDINE ’ is also a so-called trigger symbol so that stopping four or more of the symbol ‘SARDINE’ in total in any of the stop areas of the video reels21to25, not limited to the activated line, results in the shift to the bonus game. The symbol ‘WILD’ is a so-called wild symbol to be a substitute symbol except the symbol ‘SARDINE’.

Next, with reference toFIG. 6, a control unit of the slot machine1will be described.

As shown inFIG. 6, the control unit of the slot machine1is configured as the CPU50is centered. The CPU50is connected to ROM51and RAM52. The ROM51stores a main process program which is described below, a base game process program, a bonus game process program, a stop symbol determination table used for determining symbols to be stopped, a table which records winning combinations and credits paid out for the respective winning combinations (seeFIG. 9), various programs necessary to control the slot machine1, data tables, and the like. The RAM52is a memory for temporarily storing the amount of owned credits, the amount of lost credits from the time point when the insured mode is set to the present, the number of remaining free games in a bonus game, various data computed by the CPU50, and the like.

A clock pulse generator circuit53for generating a reference clock pulse is connected to the CPU50via a frequency divider54. Further connected to the CPU50are a random number generator55for generating random numbers and a random number sampling circuit56for sampling random numbers, which are used for various lotteries including a win lottery.

The CPU50controls based on the switch signals outputted from the switches embedded in the buttons13,31to40, so that various operations corresponding to each of the buttons are implemented. Moreover, the CPU50computes inserted coins based on the coin detection signal outputted from the coin sensor49, and computes credits equivalent to the bill amount based on the bill detection signal outputted from the bill sensor67.

The hopper71, which is connected to the CPU50via a hopper drive circuit70, pays out a predetermined number of coins from the coin payout opening15, when a drive signal is outputted from the CPU50to the hopper drive circuit70. The CPU50is also connected to a coin sensor73via the payout completion signal circuit72. The payout completion signal circuit72outputs a payout completion signal to the CPU50, when receiving a predetermine number of coin detection signals outputted from the coin sensor73. Moreover, the CPU50is connected to the sub display3and the main display4via a liquid crystal drive circuit74.

As shown inFIG. 7, the liquid crystal drive circuit74has program ROM81, image ROM82, an image control CPU83, work RAM84, a VDP (video display processor)85, and video RAM86. The program ROM81stores an image control program and various selection tables relating to display on the displays3and4. The image ROM82stores dot data that creates images for the insurance indicator11(seeFIG. 4) and symbols on the reel bands111to115(see.FIG. 5) displayed on the video reels21to25. The image control CPU83determines images to be displayed on the displays3and4from dot data stored in the image ROM82in accordance with the image control program stored in the program ROM81based on parameters set by the CPU50. The work RAM84is a temporary memory to be used when the image control CPU83conducts the image control program. The VDP85creates images in accordance with the determination by the image control CPU83, and outputs them to the displays3and4. Accordingly, the symbol columns included in the reel bands111to115are scrolled and displayed on the video reels21to25. The video RAM86is a temporary memory to be used when images are created by the VDP85.

An LED78, which is connected to the CPU50via an LED drive circuit77, is disposed on the front of the slot machine1in many numbers. Each LED78is controlled to be lighted by the LED drive circuit77based on a drive signal from the CPU50in making various effects. For example, the LED78is lighted to augment effects at a bonus game.

A sound output circuit79and the speakers5L and5R are connected to the CPU50. The speakers5L and5R generate sounds and sound effects in making various effects based on a signal outputted from the sound output circuit79.

A touch panel121, which is connected to the CPU50via a touch panel drive circuit122, is placed on a screen of the main display4, Coordinate position data on the position where a player touches is outputted from the touch panel121to the CPU50via the touch panel drive circuit122. The CPU50determines, based on that data, the position where the player touches, and the like.

Next, with reference toFIG. 8, each of the storage areas of the RAM52will be described.

As shown inFIG. 8, the RAM52has an owned credit data storage area52A for storing the amount of owned credits, a lost credit data storage area52B for storing the amount of lost credits, and a free game number-storage area52C which stores the number of remaining free games in a bonus game. The amount of lost credits stored in the lost credit data storage area52B is displayed on the insurance indicator11(seeFIG. 4) when the game mode is in the insured mode.

Next, the stop symbol determination table that is used for determining symbols to be stopped on the video reels21to25will be described.

The stop symbol determination table assigns code numbers ‘00’ to ‘29’ with respect to symbols included in each of the reel bands111to115inFIG. 5from above, and sets a random number corresponding to each of the code numbers. In an internal lottery process inFIG. 13which is described below, the CPU50samples, via the random number sampling circuit56, five random numbers corresponding to the video reels21to25, respectively, and determines symbols of the code numbers corresponding to the sampled random numbers as symbols to be stopped on the second stop areas212,222,232,242and252of each of the video reels21to25. For example, the sampled random number with respect to the video reel21is ‘9’, the symbol ‘FISH’ assigned to code number ‘09’ in the first reel band111is determined as a symbol to be stopped on the second stop area212of the video reel21. When symbols to be stopped on a first activated line formed in the second stop areas212,222,232,242and252are determined, symbols to be stopped above and below the second stop areas, i.e., on the first and third stop areas211,213,221,223,231,233,241,243,251and253are determined based on the symbol columns of the reel bands111to115.

Next, with reference toFIG. 9, the winning combinations and the payout numbers thereof will be described.

The payout number shown inFIG. 9is used to be added to the owned credits when the bet number is ‘1’. When the bet number is ‘2’ or greater, the value of a corresponding payout number inFIG. 9multiplied by the bet number is added to the owned credits.

InFIG. 9, a case where X number of certain symbols are continuously stopped on an activated line from the left end is expressed as ‘XK (X=2,3,4,5)’. Thus, when two, three, four and five of the symbol ‘LOBSTER’ are continuously stopped on an activated line from the left end, payout numbers ‘10’, ‘320’, ‘2500’, and ‘6000’ are obtained, respectively. When two, three, four and five of the symbol ‘SHARK’ are continuously stopped on an activated line from the left end, payout numbers ‘3’, ‘25’, ‘150’, and ‘1000’ are obtained, respectively. Similarly, for the symbols ‘FISH’, ‘PUNK’, ‘OCTOPUS’, ‘CRAB’, ‘WORM’, ‘A’, ‘K’, ‘Q’, and ‘J’, payout numbers are set respectively as shown inFIG. 9.

When winning combinations of these symbols are made on two or more activated lines, the sum of the payout numbers of all the winning combinations is added to the owned credits.

The symbol ‘SARDINE’ is a scatter symbol. That is, stopping two, three, four, five or more of the symbol ‘SARDINE’ in total in any of the stop areas of the video reels21to25, not limited to the activated line, results in payout numbers ‘2’, ‘5’, ‘10’, and ‘125’, respectively.

Only the payout number for the symbol ‘SARDINE’ shown inFIG. 9is multiplied by the total bet number which is a product of the bet number and the activated line number, and the resulted number is added to the owned credits. A payout number for another symbol such as the symbol ‘LOBSTER’, which is obtained in addition to the payout number for the symbol ‘SARDINE’, is also added to the owned credits.

The symbol ‘SARDINE’ is a trigger symbol for the shift to the bonus game. That is, stopping four or more of the symbol ‘SARDINE’ in total in any of the stop areas of the video reels21to25, not limited to the activated line, results in the shift to the bonus game as well as the payout.

Next, the bonus game will be described.

The bonus game, which is started by satisfying above-described certain conditions during the base game, is usually advantageous for a player. In the bonus game of the embodiment, so-called free games are played so that a series of 15 to 25 games are continuously played in accordance with the result of an internal lottery without betting credits.

In the bonus game, the bet number and the activated lines when shifted to the bonus game are applied. Although the winning combination and its payout number in the bonus game are the same as those in the base game, the bonus game is different from the base game in that the symbol ‘SHARK’ is treated as the symbol ‘LOBSTER’, and that the free game number is increased when four of the symbol ‘SARDINE’ in total are stopped on any of the stop areas of the video reels21to25. As shown inFIG. 9, since the symbol ‘LOBSTER’ has a higher payout number than that of the symbol ‘SHARK’, it is highly likely for a player to suppress loss of credits and to obtain many credits in the bonus game.

Next, with reference toFIG. 10, a main process of the slot machine1will be described.

Programs shown in flow charts inFIGS. 10 to 17, described below, are stored in the ROM51and/or the RAM52of the slot machine1(seeFIG. 6) and run by the CPU50.

First, as shown inFIG. 10, at Step (hereinafter, it is abbreviated to S)1, a game mode switching process, which is described below with reference toFIG. 11, is performed to switch the current game mode based on the press of the INSURE ON/OFF button13.

After the game mode switching process is performed at S1, a starting process, which is described below with reference toFIG. 12, is performed at S2. Then, based on the switch signals outputted from the LINE switches60to62, an internal lottery process, which is described below with reference toFIG. 13, is performed at S3. A base game process, which is described below with reference toFIG. 14, is performed at S4, and after that, a bonus game process, which is described below with reference toFIG. 15, is performed at S5. Subsequently, a loss compensation process inFIG. 16is performed at S6, and then the main process program is ended.

Next, with reference toFIG. 11, the game mode switching process at S1inFIG. 10will be described.

First, as shown inFIG. 11, at S11, the CPU50determines whether the INSURE ON/OFF button13is pressed, based on the switch signal from the INSURE ON/OFF switch76. When it is determined that the INSURE ON/OFF button13is not pressed (S11: NO), the game mode switching process is ended to return to the main process shown inFIG. 10, and the process is moved to the starting process (S2). When it is determined that the INSURE ON/OFF button13is pressed (S11: YES) it is determined whether the game mode is in the insured mode (S12).

When it is determined that the gaze mode is in the uninsured mode (S12: NO), the game mode is switched to the insured mode (S13) to apply the compensation function. In the insured mode where the compensation function works, for compensation of collecting one credit as an insurance fee (S27), as shown inFIG. 16, when the amount of lost credits is equal to or more than the upper limit, credits are paid for compensation for a loss (S74).

At S14, the amount of lost credits, which is stored in the lost credit data storage area52B in the RAM52, is read. At S15, based on the amount of lost credits read at S14, the insurance indicator11(seeFIG. 4) is displayed on the main display4. Then, the process is returned to S11.

When it is determined that the game mode is in the insured mode (S12: YES), the game mode is switched to the uninsured mode (S16) where a game is processed without applying the loss compensation function as described above.

At S17, the insurance indicator11deleted from the main display4. Then, the process is returned to S11.

Next, with reference toFIG. 12, the starting process at S2inFIG. 10will be described.

First, as shown inFIG. 12, at S21, the CPU50determines whether a predetermined time period (for example, 15 seconds) has elapsed. When it is determined that a predetermined time period has not elapsed (S21: NO), the process is moved to S23. When it is determined that a predetermined time period has elapsed (S21: YES), an image for demonstration effects is displayed on the sub display3and/or the main display4at S22, and then the process is moved to S23.

At S23, a coin/bill receiving process is performed so as to increase the owned credits based on coins inserted through the coin insertion slot9and the bills inserted through bill insertion slot10. More specifically, when a coin is detected by the coin sensor49, the amount of owned credits stored in the owned credit data storage area52A in the RAM52is increased by one. Furthermore, when a bill is detected by the bill sensor67, the amount of owned credits stored in the owned credit data storage area52A in the RAM52is increased by the credits equivalent to the amount of the bill detected. Assuming that ten cents corresponds to one coin, a one-dollar bill is equivalent to ten credits. Then, in association with change of the amount of owned credits, the numeric shown on the owned credits display part12is updated.

At S24, the CPU50determines whether any one of the PLAY buttons37to39is pressed. When it determines that any one of the PLAY buttons37to39is not pressed (S24: NO) the process is returned to S21to repeat the process described above. When it determines that any one of the PLAY buttons37to39is pressed (S24: YES), the process is moved to S25even during demonstration effects.

At S25, it is determined whether the game mode is in the insured mode. When it is determined that the game mode is in the uninsured mode (S25: NO), the total bet number is subtracted from the owned credits (S26). More specifically, the amount of owned credits stored in the owned credit data storage area52A in the RAM52is read, the total bet number is subtracted from the owned credits, and the resulted owned credit data is written to the RAM52. Then, in association with change of the amount of owned credits, the numeric shown on the owned credits display part12is updated. After that, the starting process is ended.

When it is determined that the game mode is in the insured mode (S25: YES), the value that the total bet number is added with one credit as an insurance fee is subtracted from the owned credit (S27). For example, when five pay lines are activated and the bet number per line is five bets by the BET 5 PER LINE button35and the PLAY 5, LINES button38, the total bet number is twenty-five and the subtracted value is twenty-six. Here, the amount of owned credits stored in the owned credit data storage area52A in the RAM52is read, the total bet number and one credit as an insurance fee are subtracted from the owned credits, and the resulted owned credit data is written to the RAM52. Then, in association with change of the amount of owned credits, the numeric shown on the owned credits display part12is updated.

After that, at S28, the amount of lost credits stored in the lost credit data storage area52B in the RAM52is read, the total bet number and one credit as an insurance fee are added to the lost credits, and the lost credit data is updated.

At S29, based on the lost credit data updated at S28, display of the insurance indicator11(seeFIG. 4) is updated. More specifically, the gage area89is extended rightward by the area corresponding to the added credits, and the numeric shown in the lost amount display part93is increased by the credits spent this time. After that, the starting process is ended.

Next, with reference toFIG. 13, the internal lottery process at S3inFIG. 10will be described.

First, as shown inFIG. 13, at S31, symbols to be stopped on the video reels21to25are determined. More specifically, as described above, five random numbers each corresponding to the video reels21to25are sampled by the random number sampling circuit56, the stop symbol determination table is referenced to determine symbols of the code numbers (seeFIG. 5) corresponding to the sampled random numbers for each of the video reels21to25. When the symbols to be stopped on the second stop areas212,222,232,242and252of the video reels21to25are determined in this manner, symbols to be stopped above and below the second stop areas, i.e., on the first and third stop areas211,213,221,223,231,233,241,243,251and253are determined based on the symbol columns of the reel bands111to115inFIG. 5.

After the symbols to be stopped on the video reels21to25at S31are determined, the winning combination on the activated line and the payout number thereof are determined at S32based on the table inFIG. 9. Then, the process is returned to the main process to move to the base game process at S4inFIG. 10.

Next, with reference toFIG. 14, the base game process at S4inFIG. 10will be described.

First, as shown inFIG. 14, at S41, based on the switch signal from the switch60to62corresponding to any one of the PLAY buttons37to39that is determined as pressed at S24in the starting process (S2), symbols are started to be scrolled and displayed on the video reels21to25.

After that, scrolling is stopped, and the symbols determined at S31inFIG. 13are stopped on the video reels21to25(S42). At S43, paid out are credits that correspond to the payout number determined at S32inFIG. 13in accordance with the symbols stopped on the activated line. Here, the amount of owned credits stored in the owned credit data storage area52A in the RAM52is read, the paid out credits are added, to the owned credits, and the resulted owned credit data is written. Then, in association with change or the amount of owned credits, the numeric shown on the owned credits display part12is updated.

At S44, it is determined whether the game mode is in the insured mode. When it is determined that the game mode is in the uninsured mode (S44: NO), the base game process is ended with the mode kept. When it is determined that the game mode is in the insured mode (S44: YES), the amount of lost credits stored in the lost credit data storage area52B in the RAM52is read to subtract the credits paid out at S43, and the lost credit data is updated (S45).

At S46, based on the lost credit data updated at S45, display of the insurance indicator11(seeFIG. 4) is updated. More specifically, the gage area89, is reduced leftward by the area corresponding to the subtracted credits, and the numeric shown in the lost amount display part93is decreased by the credits obtained at this time. After that, the base game process is ended.

Next, with reference toFIG. 15, the bonus game process at S5inFIG. 10will be described.

First, as shown inFIG. 15, at S51, it is determined whether a player wins a bonus game. More specifically, when it is determined that four or more of the symbol ‘SARDINE’, which is a trigger symbol for the shift to the bonus game, are stopped on any of the stop areas of the video reels21to25in the internal lottery process (S3) inFIG. 10, it is determined that a player wins a bonus game (S51: YES), and the process is moved to S52. When it is determined that a player does not win a bonus game (S51: NO), the bonus game process is ended to return to the loss compensation process (S6) in the main process inFIG. 10.

At S52, the free game number T is determined by lottery among any one of 10 to 25 games based on the random number sampled by the random number sampling circuit56. The free game number T thus determined is stored in the free game number storage area52C in the RAM52.

At S53, the symbols to be stopped on the video reels21to25are determined. The symbols to be stopped are determined for each of the video reels21to25, as similar to S31inFIG. 13.

After the symbols to be stopped on the video reels21to25are determined at S53, based on the table inFIG. 9, the winning combination on the activated line and the payout number are determined (S54). It should be noted that in the bonus game, the symbol ‘SHARK’ is treated as the symbol ‘LOBSTER’ as described above.

At S55, it is determined whether the player wins the bonus game in symbol determination by the internal lottery at S53. Here, as similar to S51, when it is determined that four or more of the symbol ‘SARDINE’, which is a trigger symbol for the shift to the bonus game, are stopped on any of the stop areas of the video reels21to25, it is determined that the player wins the bonus game (S55: YES), and then the process is moved to S56. When it is determined that the player does not win the bonus game (S55: NO), S56is skipped to move to S57.

At S56, the game number ‘t’ for the free game is newly determined by lottery, and the game number ‘t’ is added to the free game number T (S56). Therefore, when a player wins a bonus game during the bonus game, the number of the remaining free games in the current bonus game is increased. For example, in a bonus game having the free game number20, when a player wins a 17 games at the twelfth free game, the player can play free games for 25 games (20 games−12 games+17 games) after that.

At S57, as similar to S41in the base game process, the symbols are scrolled and displayed on the video reels21to25. After that, at S58, as similar to S42in the base game process, scrolling is stopped, and the symbols determined at S53are stopped on the video reels21to25. At S59, credits corresponding to the payout number, which is determined at S54in accordance with the symbols stopped on the on the activated line, are paid out.

At S60, it is determined whether the game mode is in the insured mode. When it is determined that the game mode is in the uninsured mode (S60: NO), the process is moved to S63. When it is determined that the game mode is in the insured mode (S60: YES), the amount of lost credits stored in the lost credit data storage area52B in the RAM52is read to subtract the credits paid out at S59, and the lost credit data is updated (S61)

At S62, based on the lost credit data updated at S61, display of the insurance indicator11is updated. More specifically, the gage area89is reduced leftward by the area corresponding to the subtracted credits, and the numeric shown in the lost amount display part93is decreased by the credits obtained at this time. After that, the process is moved to S63.

At S63, the CPU50reads the free game number T stored in the free game number storage area52C in the RAM52, subtracts ‘1’ from the read number T, and stores the subtracted number in the RAM52.

Then, the CPU50determines whether the free game number T stored in the RAM52is zero (S64). In other words, it is determined whether the free game will be performed. When the free game number T is not zero (S64: NO), the process is returned to S53to repeat the process, described above. When the free game number T is zero (S64: YES), the bonus game process is ended.

Next, with reference toFIG. 16, the loss compensation process at S6inFIG. 10will be described.

First, at S71inFIG. 16, it is determined whether the game mode is in the insured mode. When it is determined that the game mode is in the uninsured mode (S71: NO), the loss compensation process is ended.

When it is determined that the game mode is in the insured mode (S71: YES), the amount of lost credits stored in the lost credit data storage area52B in the RAM52(S72) is read. Then, it is determined whether the amount of lost credits read at S72is equal to or more than the upper limit (S73). When it is determined that the amount of lost credits is less than the upper limit (S73: NO), the loss compensation process is ended. When it is determined that the amount of lost credits is equal to or more than the upper limit (S73: YES), 100 credits are paid out (S74).

After that, the amount of lost credits stored in the lost credit data storage area52B in the RAM52is initialized to ‘0’ (S75). At S76, based on the amount of lost credits initialized at S75, display of the insurance indicator11is updated. More specifically, the numeric of the lost amount display part93is turned to ‘0’ to remove the area of the gage area89(seeFIG. 4). After that, the loss compensation process is ended.

Then, with reference toFIG. 17, an interruption process program performed in the slot machine1will be described.

The interruption process program is performed at every fixed time period during the main process inFIG. 10, at every 4 ms, for example, to initialize each of the amounts of credits stored in the RAM52in accordance with the press of the COLLECT button31.

First, as shown inFIG. 17, the CPU50determines whether the COLLECT button31is pressed at S81. When it is determined that the COLLECT button31is not pressed (S81: NO), the interruption process is ended. When it is determined that the COLLECT button31is pressed (S81: YES), it is determined whether a player is playing a game (S82). Here, assuming that a game is being played from the time point when the CPU50receives the switch signal outputted from any-one of the switches57to62based on the press of the BET buttons33to35and the PLAY buttons37to39to the end of the loss compensation process (S6).

When it is determined that the game is being played (S82: YES), the interruption process is ended even when the switch signal is received from the COLLECT switch45. When it is determined that the game is not being played (S82: NO), the coins corresponding to the amount of owned credits stored in the owned credit data storage area52A in the RAM52are paid out (S83).

After that, the data stored in the owned credit data storage area52A and in the lost credit data-storage area52B in the RAM52are both initialized to ‘0’ (S84). Then, the interruption process is ended.

As described above, according to the slot machine1of the first embodiment, based on the press of the INSURE ON/OFF button13, the game mode is switched between the insured mode where the compensation function works and the uninsured mode where the compensation function does not work. In other words, a-player can select whether or not to apply the compensation function by his/her intention. Thus, player's satisfaction can be increased.

The insurance indicator11is disposed on the main display4, which displays a bar graph (seeFIG. 4) representing the amount of lost credits from the time point when the insured mode is set to the present and the required amount of lost credits for compensation. Since the insurance indicator11is displayed only when the game mode is in the insured mode, a player seeing the insurance indicator11displayed on the main display4can know that the game mode is in the insured mode. Furthermore, a player can confirm the amount of lost credits as seeing the insurance indicator11, and can select whether or not to apply the compensation function properly in accordance with the current game condition.

Since the insurance indicator11(seeFIG. 4) displays the amount of lost credits (‘1700’ inFIG. 4) as well as the upper limit thereof (‘2000’ inFIG. 4), a player can know a guideline until credits for compensation are paid out, and can select whether or not to apply the compensation function further properly.

Since the insurance indicator11(seeFIG. 4) displays the amount of lost credits and the upper limit by graph, the player can know a guideline until credits for compensation are paid out intuitively, quickly.

When the game mode is in the uninsured mode, the insurance indicator11(seeFIG. 4) is not displayed (see S16and S17FIG. 11). Therefore, the player can know that the game mode is in the uninsured mode when the insurance indicator11is not displayed on the main display4. Moreover, since the insurance indicator11is not displayed in the uninsured mode, the player can play games in more concentration.

In accordance with pressing the COLLECT button31, it is determined that the game is ended and the change of player is detected, so that the lost credit data stored in the RAM52is initialized (S84inFIG. 17). Therefore, the following can be avoided: a player plays games on a gaming machine for a while with no win and moves to another gaming machine, and another player who sits down right after the previous player has gone takes over the previous player's lost credits and receives a payout of credits by lost credits smaller than usual; a player playing on a gaming machine continuously wins to receive a payout of many credits and then moves to another gaming machine, and another player who sits down right after the previous player has gone cannot obtain credits for compensation even though he/she loses the upper limit. In the embodiment, even though a player plays games at the same slot machine1for a long time in a game shop where many slot machines1are placed, for example, or even though a player changes the slot machine1for playing games, the player can receive a proper compensation based on his/her game result. Therefore, the player can be assured to play games.

Next, with reference to FIG,18, an exemplary modification of the starting process shown inFIG. 12will be described.

In the exemplary modification, instead of further subtracting one credit as in the example shown inFIG. 12, coins and bills are exchanged into credits in a rate lower than the usual rate in the coin/bill receiving process (seeFIG. 19) to collect an insurance fee. More specifically, inserted coins and bills are exchanged into credits in a rate of 97% to be the owned credits, and the remaining 3% is collected as an insurance fee. Here, one coin corresponds to one credit.

First, at S101and S102, the same steps are performed as S21and S22inFIG. 12, respectively. At S103, based on coins inserted from the coin insertion slot9and bills inserted from the bill insertion slot10, a coin/bill receiving process is performed to increase the owned credits.

Here, the coin/bill receiving process at S103will be described with reference toFIG. 19.

First, at S111, the CPU50determines whether a coin is inserted based on the signal from the coin sensor49. When it determines that a coin is inserted (S111: YES), it determines whether the game mode is in the insured mode (S112). When it is determined that the game mode is in the uninsured mode (S112: NO), one credit is added to owned credits the amount of which is stored in the owned credit data storage area52A in the RAM52(S113). Then, in association with charge of the amount of credits, the numeric shown in the owned credits display part12is updated. After that, the process is returned to S111.

When it is determined that the game mode is in the insured mode (S112: YES), 0.97 credit is added to the owned credits the amount of which is stored in the owned credit data storage area52A in the RAM52(S114). Subsequently, in association with change of the amount of owned credits, the numeric displayed on the owned credits display part12is updated. After that, the process is returned to S111.

When it is determined that no coin is inserted (S111: NO), the CPU50determines based on the signal from the bill sensor67at S115whether a bill is inserted from the bill insertion slot10. When it is determined that a bill is inserted (S115: YES), the CPU50computes the number of coins equivalent to the amount of the bill inserted (S116)

After that, at S117, it is determined whether the game mode is in the insured mode. When it is determined that the game mode is in the uninsured mode (S117: NO), credits equivalent to the coins computed at S116are added to the owned credits as one coin is one credit (S118). Then, in association with change of the amount of owned credits, the numeric displayed on the owned credits display part12is also updated. After that, return to111.

When it is determined that the game mode is in the insured mode (S117: YES), credits equivalent to the coins computed at S116are added to the owned credits as one coin is 0.97 credit (S119). Then, in association with change of the amount of credits, the numeric displayed on the owned credits display part12is updated. After that, the process is returned to S111.

When it is determined that no bill is inserted (S115: NO), the coin/bill receiving process is ended to move to S104inFIG. 18.

At S104, the same step is performed as S24inFIG. 12. When it is determined that any one of the PLAY buttons37to39is not pressed (S104: NO), the process is returned to S101to repeat the process described above. When it is determined that any one of the PLAY buttons37to39is pressed (S104: YES), the process is moved to S105even during demonstration effects.

At S105, as similar to S26inFIG. 12, the total bet number is subtracted from the owned credits (S105). At S106, as similar to S25inFIG. 12, it is determined whether the game mode is in the insured mode. When it is determined that the game mode is in the uninsured mode (S106: NO), the starting process is ended.

When it is determined that the game mode is in the insured mode (S106: YES), the amount of lost credits stored in the lost credit data storage area52B in the RAM52is read, the total bet number is added to the lost credits, and the lost credit data is updated (S107). At S108, as similar to S29inFIG. 12, based on the lost credit data updated at S107, display of the insurance indicator11(seeFIG. 4) is updated. After that, the starting process is ended.

Next, with reference toFIGS. 20 and 21, an exemplary modification of the internal lottery process shown inFIG. 13will be described.

In the example shown inFIG. 13, five random numbers each corresponding to the video reels21to25are sampled by the random number sampling circuit56(seeFIG. 6), and the symbols to be stopped on each of the video reels21to25are determined based on the code numbers corresponding to each of the random numbers (seeFIG. 5). However, in the exemplary modification, a single random number is sampled to be used for directly determining the winning combination.

When the winning combination is determined at S201inFIG. 20, a lottery table101shown inFIG. 21is used. In the lottery table101, the winning combinations are associated with the random numbers in a predetermined range. When the random number sampled by the random number sampling circuit56ranges within 0 to 49, it is determined that a player wins a bonus game. More specifically, it is determined that four or more of the symbol ‘SARDINE’ are stopped, not limited to on the activated line, in any of the stop areas of the video reels21to25. When the random number ranges within 50 to 51, 52 to 57, 58 to 97, 98 to 177, 178 to 277, 278 to 477, 478 to 777, 778 to 1177, 1178 to 1577, 1578 to 1977, and 1978 to 2377, it is determined that the winning combinations of ‘LOBSTER’, ‘SHARK’, ‘FISH’, ‘PUNK’, ‘OCTOPUS’, ‘CRAB’, ‘WORM’, ‘A’, ‘K’, ‘Q’ and ‘J’ are made, respectively. When the random number ranges within 2378 to 2577, it is determined that the winning combination of ‘SARDINE’ is made. More specifically, it is determined that three of the symbol ‘SARDINE’ are stopped, not limited to on the activated line, in any of the stop areas of the video reels21to25. When the random number ranges within 2578 to 11999, it is determined that no winning combination is made, which means a miss.

Next, with reference toFIGS. 22A,22B,23,24, and25, a slot machine of a second embodiment of the gaming machine according to the invention will be described.

The compensation function that compensates for a loss due to games works when the amount of lost credits reaches the upper limit so that, in the first embodiment, a predetermined number of credits are paid out in the first embodiment, while in the second embodiment, it works so that a player compulsorily wins a mystery bonus game as described below.

In the embodiment, in addition to the bonus game shown inFIG. 15as described above (hereinafter, in the embodiment, it is called ‘a basic bonus game’), a so-called mystery bonus game is performed. Usually, the basic bonus game is started when the bonus winning combination of symbols disclosed to a player is made. On the other hand, the mystery bonus game is started when a mystery bonus game winning combination not disclosed to a player is made. Here, ‘being disclosed’ means that information is given to a player as determined information by displaying it on display3or4, for example. Such information is given to a player from a party who knows, based on authenticated authority, information such as determination logic for the CPU50stored in the slot machine1, e.g., developers, manufacturers and venders of the slot machine1, or from a party who knows the information through permission from that party, e.g., owners and operators at a game shop, a game arcade, and a casino where the slot machine1is placed. In reverse to the meaning of ‘being disclosed’, ‘not being disclosed’ means that information is not given as determined information.

As similar to the basic bonus game, the mystery bonus game is a game usually advantageous for a player, and the game contents are the same as those of the basic bonus game. That is, during the mystery bonus game, so-called free games are played so that a series of 15 to 25 games are continuously played in accordance with the result of an internal lottery without betting-credits. Further, as similar to the basic bonus game, in the mystery bonus game, the bet number and the activated lines when shifted to the game are applied. Furthermore, the winning combination and its payout number in the mystery bonus game are the same in those in the basic bonus game described above. Thus, the symbol ‘SHARK’ shown inFIG. 9is treated as the symbol ‘LOBSTER’, and the free game number is increased when four of the symbol ‘SARDINE’ in total are stopped on any of the stop areas of the video reels21to25. Therefore in the mystery bonus game, as similar to the basic bonus game, the player can suppress use of credits and is likely to obtain many credits.

In the embodiment, depending on whether the game mode is either in the uninsured mode or the insured mode, the mystery bonus game winning combination is varied (seeFIG. 22A and 22B)

When the game mode is in the uninsured mode, patterns A, B and C shown inFIG. 22Aare applied as the mystery bonus game winning combinations. When any of the patterns A to C is made, a mystery bonus game is started. The pattern A means that the symbols ‘LOBSTER’, ‘FISH’, ‘CRAB’, and, ‘SHARK’ are continuously stopped on the activated line from the left end, the pattern B means that the symbols ‘OCTOPUS’ ‘PUNK’, ‘WORM’, and ‘A’ are continuously stopped on the activated line from the left end, and the pattern C means that the symbols A’, ‘K’, ‘Q’, and ‘J’ are continuously stopped on the activated line from the left end.

When the game mode is in the insured mode, patterns D, E and F shown inFIG. 22Bare applied as the mystery bonus game winning combinations. When any of the patterns D to F is made, a mystery bonus game is started. The pattern D means that the symbols ‘LOBSTER’, ‘FISH’, and ‘CRAB’ are continuously stopped on the activated line from the left end, the pattern B means that the symbols ‘OCTOPUS’, ‘PUNK’, and ‘WORM’ are continuously stopped on the activated line from the left end, and the pattern C means that the symbols ‘A’, ‘K’, and ‘Q’ are continuously stopped on the activated line from the left end.

In other words, the symbols to be stopped on the video reel25is not specified in the uninsured mode, while the symbols to be stopped on the video reels24and25are not specified in the insured mode. Thus, in the insured mode, types of mystery bonus winning combinations are more than that in the uninsured mode, so that a probability of winning a mystery bonus game is higher than that in the uninsured mode. Further, as described below, when the amount of lost credits reaches the upper limit in the insured mode, a player compulsorily wins a mystery bonus game (seeFIG. 25) to compensate for the player's loss.

Next, with reference toFIG. 23, a main process in the embodiment will be described.

It is different from that of the first embodiment inFIG. 10in that after a base game process at S4, not the bonus game process at S5but a basic bonus game process at S7and a mystery bonus game process at S8are performed, and in that the loss compensation process S6is omitted. Furthermore, the contents of a game mode switching process at S10and an internal lottery process at S9are different. Hereinafter, the differences from the first embodiment will be described. Each program shown in flow charts inFIGS. 23 to 25is stored in the ROM51and/or the RAM52of the slot machine1, and is run by the CPU50.

The game mode switching process at S10is shown inFIG. 24. The difference fromFIG. 11is in that the probability of winning the mystery bonus game is increased (S18) after the game mode is switched to the insured mode at S13and before credit data is read (S14), and that the probability of winning the mystery bonus game is decreased (S19) after the game mode is switched to the uninsured mode at S16and before display of the insurance indicator11is deleted (S17). Here, in order to increase the probability of winning the mystery bonus game, not the combinations shown inFIG. 22Bbut the combinations shown inFIG. 22Aare applied as the mystery bonus game winning combinations. On the other hand, in order to decrease the probability of winning the mystery bonus game, not the combinations shown inFIG. 22Abut the combinations shown inFIG. 22Bare applied as the mystery bonus game winning combination.

The internal lottery process at S9is shown inFIG. 25. First, as same as S71in the loss compensation process shown inFIG. 16, it is determined whether the game mode is in the insured mode. When it is determined that the game mode is in the uninsured mode (S71: NO), the same steps are performed as S31and S32shown inFIG. 13. Here, at S32, the mystery bonus game winning combinations shown inFIG. 22A, in addition to the table inFIG. 9, are referenced to determine a winning combination and its payout number.

When it is determined that the game mode is in the insured mode (S71: YES), the same steps of S72and S73as in the loss compensation process shown inFIG. 16are performed. When it is determined that the amount of lost credits is less than the upper limit (S73: NO), the same steps are performed as S31and S32shown inFIG. 13.

When it is determined that the amount of lost credits is equal to or more than the upper limit (S73: YES), instead of paying out credits inFIG. 16(S74), it is determined to compulsorily win the mystery bonus game (S36). Then, at S37, the symbols to be stopped on the video reels21to25are determined so as to make the mystery bonus game winning combination shown inFIG. 22B. After that, the same steps are performed as S75and S76in the loss compensation process shown inFIG. 16.

Each of the basic bonus game process at S7and the mystery bonus game process at S8shown inFIG. 23is substantially the same process as the bonus game process in the first embodiment described above (seeFIG. 15). In other words, the phrase ‘the bonus game’ inFIG. 15can be replaced by ‘the basic bonus game’ and ‘the mystery bonus game’, respectively, and thus the descriptions of the bonus game process at S7and at S8will be omitted herein.

When the mystery bonus game winning combination is made during the basic bonus game, the game may be shifted to the mystery bonus game.

As described above, according to the embodiment, when made is the combination of symbols that is not disclosed to a player, i.e., the combination that the player regards as a miss, the player wins the mystery bonus game at unexpected timing. Therefore, the player's expectations for games can be increased, and the player can be prevented from being board with games.

Next, with reference toFIGS. 26A,26B, and27, an exemplary modification of the second embodiment will be described.

In the second embodiment, at S31in the internal lottery process (seeFIG. 25), five random numbers are sampled each corresponding to the video reels21to25by the random number sampling circuit56(seeFIG. 6), and the symbols to be stopped on each of the video reels21to25are determined based on the code number corresponding to each of the random numbers (seeFIG. 5). On the other hand, in the exemplary modification, a single random number is sampled to be used for directly determining the winning combination.

Here, whether or not to win the mystery bonus game is determined by using the lottery table102or103(seeFIGS. 26A and 26B). The lottery table used is varied depending on whether the game mode is either in the uninsured mode or the insured mode. In the insured mode, the random numbers for winning a bonus game are more than that in the uninsured mode. Therefore, as similar to the second embodiment described above, in the insured mode a probability of winning the mystery bonus game is higher than that in the uninsured mode.

In the exemplary modification, at S18in the game mode switching process (seeFIG. 24), the table is changed from the table102shown inFIG. 26Ato the table103shown inFIG. 26Bin order to increase the probability of winning the mystery bonus game. At S19, the table is changed from the table103shown inFIG. 26Bto the table102, shown inFIG. 26Ain order to decrease the probability of winning the mystery bonus game.

Next, with reference toFIGS. 27A,27B,27C,28,29, and30, a slot machine of a third embodiment of the gaming machine according to the invention will be described.

The compensation function that compensates for a loss due to games in the embodiment is to increase the winning probability, not to pay out credits in the first embodiment, or not to compulsorily win the mystery bonus game in the second, embodiment. More specifically, in the embodiment, the winning probability is increased by changing the reel bands displayed on the video reels21to25to those more including advantageous symbols such as the symbols ‘SARDINE’ and ‘WILD’.

In the embodiment, in addition to the uninsured mode and the insured mode, a high probability mode is provided. When the amount of lost credits reaches the upper limit in the insured mode, the game mode is switched to the high probability mode, and that game mode is maintained until a predetermined ending condition is satisfied. Depending on the modes, the reel bands displayed on the video reels21to25are varied.

In the uninsured mode, as similar to the first embodiment, the first reel band111to the fifth reel band115shown inFIG. 5are applied to the video reels21to25, respectively (seeFIG. 27A). In the insured mode, a sixth reel band116is applied to the video reel21instead of the first reel band111, and the second reel band112to the fifth reel band115are applied to the remaining video reels22to25, respectively (seeFIG. 27B). In the high probability mode, a seventh reel band117is applied to the video reel21instead of the first reel band111or the sixth reel band116, and the second reel band112to the fifth reel band115are applied to the remaining video reels22to25, respectively (seeFIG. 27C).

As shown inFIG. 28, as compared with the first reel band111(seeFIG. 5), the sixth reel band116more includes the symbols ‘WILD’ and ‘SARDINE’. More specifically, the first reel band111includes only two symbols ‘WILD’, whereas the sixth reel band116includes four symbols. Furthermore, the first reel band111includes only one symbol ‘SARDINE’, whereas the sixth reel band116includes three symbols.

Moreover, as compared with the first and the sixth reel bands111and116, the seventh reel band117more includes the symbols ‘WILD’ and ‘SARDINE’. More specifically, the first and the sixth reel bands111and116include two and four symbols ‘WILD’, respectively, whereas the seventh reel band117includes eight symbols. Besides, the first and the sixth reel bands111and116include one and three of the symbol ‘SARDINE’, respectively, whereas the seventh reel band117includes five of the symbol ‘SARDINE’.

Having more symbols ‘WILD’, which is a substitute of the symbols other than the symbol ‘SARDINE’, raises the probability of making any of the winning combination inFIG. 9. Further, having more symbols ‘SARDINE’ raises the probability of obtaining the payout number. The symbol ‘SARDINE’ is a scatter symbol so that stopping two or more of the symbol ‘SARDINE’ in total in any of the stop areas of the video reels21to25, not limited to the activated line, results in a predetermined payout number. Moreover, since the symbol ‘SARDINE’ is also a trigger symbol for the shift to the bonus game, having more symbols ‘SARDINE’ raises the probability of winning the bonus game.

That is, a player can obtain much more payout numbers by the same bet number in the insured mode than in the uninsured mode, or in the high probability mode than in the insured mode and the uninsured mode.

In the slot machine of the embodiment, the same main process is performed as that inFIG. 10. However, it should be noted that when the symbols to be stopped are determined in the internal lottery process at S3(see S31inFIG. 13), the reel bands corresponding to each mode are used (seeFIG. 27AtoFIG. 27C). In addition, the loss compensation process S6is different from that inFIG. 16.

Here, with reference toFIG. 29, the loss compensation process at S6performed in the slot machine of the embodiment will be described.

First, the same step is performed as S71inFIG. 16. When it is determined that the game mode is in the uninsured mode (S71: NO), the loss compensation process is ended. When it is determined that the game mode is in the insured mode (S71: YES), it is determined whether or not the game mode is set in the high probability mode (S172). When it is determined that the game mode is in the high probability mode (S172: NO), the same steps are performed as S72and S73inFIG. 16. When it is determined that the amount of lost credits is less than the upper limit (S73: NO), as similar to the process in the first embodiment inFIG. 16, the loss compensation process is ended.

When it is determined that the amount of lost credits is equal to or more than the upper limit (S73: YES), the game mode is switched to the high probability mode (S175). After that, the same steps are performed as those at S75and S76inFIG. 16, and the loss compensation process is ended.

When it is determined that the game mode is in the high probability mode (S172: YES), it is determined whether the ending condition is satisfied (S173). The ending condition may be a condition where the number of performed games after the high probability mode is set reaches 20 games, a predetermined time period has elapsed after the high probability mode is set, a predetermined number of credits paid out after the high probability mode is set, or the payout rate reaches a predetermined value, e.g., 90%. The ending condition may be various not limited to the above.

When it is determined that the ending condition is satisfied (S173: YES), the game mode is switched from the high probability mode to the insured mode (S174). After that, the process is moved to S72to perform the same steps described above. When it is determined that the ending condition is not satisfied (S173: NO), the loss compensation process is ended while the game mode is maintained in the high probability mode.

In the third embodiment, a single random number may be sampled, not sampling five random numbers corresponding to the respective video reels21to25, to be used for directly determining the winning combination as in the above modification. The lottery table may be varied depending on the modes.

For example, the lottery table101inFIG. 21is used in the uninsured mode, and a lottery table104inFIG. 30is used in the insured mode. In the lottery table104, the random numbers for the winning combination are more than that in the lottery table101, so that the winning probability is increased. In the high probability mode, such a lottery table is used as the random numbers for the winning combination are much more than that in the lottery table104of the insured mode, so that the winning probability is further increased.

Next, with reference toFIGS. 31,32,33,34, and35, a slot machine of a fourth embodiment of the gaming machine according to the invention will be described.

In the fourth embodiment, the mystery bonus game described in the second embodiment is played, and a special mode, where the probability of winning the mystery bonus game is further increased, as well as the uninsured mode and the insured mode is provided.

As the mystery bonus game winning combinations, combinations shown inFIGS. 22A and 22Bare applied in the uninsured mode and the insured mode, respectively, and the patterns G, H and I inFIG. 31are used in the special mode. In the patterns G, H and I, symbols to be stopped on the video reels23,24and25are not specified. Thus, in the special mode, types of mystery bonus winning combinations are more than that in the uninsured mode and the insured mode, so that a probability of winning a mystery bonus game is higher than that in the uninsured made and the insured mode.

The main process in the fourth embodiment shown inFIG. 32is similar to the main process of the second embodiment (seeFIG. 23), but different in that a loss compensation process at S406is performed after the mystery bonus game process at S8, and in that the internal lottery process at S3which is the same as that in the first embodiment is performed instead of the internal lottery process at S9inFIG. 23in the second embodiment.

In the loss compensation process at S406, as shown inFIG. 33, first, the same step is performed as S71inFIG. 16. When it is determined that the game mode is in the uninsured mode (S71: NO), the loss compensation process is ended. When it is determined that the game mode is in the insured mode (S71: YES), it is determined whether the game mode is in the special mode (S272). When it is determined that the game mode is not in the special mode (S272: NO), the same steps are performed as S72and S73inFIG. 16. When it is determined that the amount of lost credits is less than the upper limit (S73: NO), as similar to the first embodiment shown inFIG. 16, the loss compensation process is ended.

When it is determined that the amount of lost credits is equal to or more than the upper limit (S73: YES), the game mode is switched to the special mode (S275). After that, the same steps are performed as S75and S76inFIG. 16, and then the loss compensation process is ended.

When it is determined that the game mode is in the special mode (S272: YES), it is determined whether the ending condition is satisfied (S273). The ending condition may be a condition where a player wins the mystery bonus game at this game, the number of performed games after the special mode is set reaches a predetermined number, a predetermined time period has elapsed after the special mode is set, a predetermined number of credits is paid out after the special mode is set, or a payout rate reaches a predetermined value, e.g., 90%. The ending condition may be various not limited to the above.

When it is determined that the ending condition is satisfied (S273: YES), the game mode is switched from the special mode to the insured mode (S274). After that, the process is moved to S72to perform the same steps described above. When it is determined that the ending condition is not satisfied (S273: NO), the loss compensation process is ended while the game mode is maintained in the special mode.

In the fourth embodiment, a single random number may be sampled, not sampling five random numbers each corresponding to the video reels21to25, to be used for directly determining the winning combination. The lottery table may be varied depending on the modes. For example, the lottery tables102and103inFIGS. 26A and 26Bmay be used in the uninsured mode and the insured mode, respectively, and a lottery table105inFIG. 34may be used in the special mode to determine whether a player wins the mystery bonus game. The lottery table105inFIG. 34has random numbers for the win more than that in the lottery tables102and103. Therefore, in the special mode a probability of winning ‘the mystery bonus game ’ is higher than that in the uninsured mode and the insured mode.

In addition, the mystery bonus game may have the game contents different from the basic bonus game. For example, the symbols to be displayed on the video reels21to25and the winning combination of symbols may be changed so that the mystery bonus game is more advantageous for a player than the basic bonus game.

The mystery bonus game winning combination is not limited toFIGS. 22A and 22B, as long as not disclosed to the player. For example, it is not limited to stopping on the activated line as shown inFIGS. 22A and 22B. A player may win the mystery bonus game when predetermined symbols are stopped on the stop areas of the video reels21to25by a predetermined number or greater. In addition to this, various mystery bonus game winning combinations can be applied.

Next, with reference toFIGS. 35,36,37, and38, a slot machine150of a fifth embodiment of the gaming machine according to the invention will be described. Hereinafter, the same components as those of the slot machine1in the first embodiment are assigned the same numerals and signs, omitting the description.

As shown inFIG. 35, the slot machine150of the embodiment has a card insertion slot156, which is formed on the front of the control panel6and into which a member card151is inserted. Adjacent to the card insertion slot156in the cabinet2, a card sensor153for detecting the member card151and a card reader154for reading data recorded on the member card151are disposed (seeFIG. 36)

In the embodiment, it is determined whether a player is a member based on information recorded on the member card151. Only when the player is identified as a member, the game mode can be switched through the INSURE ON/OFF button13. A player inputs his/her personal data such as name and address for member registration through a dedicated terminal placed in a game shop or over the Internet, so as to obtain the member card151which is issued with an ID number recorded thereon. The member card151may be IC card having an IC tag built therein, a magnetic card having a magnetic strip, or the like.

Next, with reference toFIG. 36, a control unit of the slot machine150will be described.

The control unit of the slot machine150is substantially the same as the control unit of the slot machine1of the first embodiment (seeFIG. 6), but it further has the card sensor153, the card reader154, and a communication circuit155for the communication with a server (not shown) which is placed in the same game shop. The control unit of the slot machine150has RAM152different from the RAM52in the first embodiment. As shown inFIG. 37, the RAM152further includes a member ID storage area52D which stores the ID numbers of all the members of a game shop in addition to the RAM52of the first embodiment (seeFIG. 8).

The card sensor153, the card reader154, and a communication circuit155are connected to a CPU50. The CPU50receiving a card detection signal from the card sensor153determines whether a player is a member, based on the member ID number read by the card reader154and on data stored in the member ID storage area52D in the RAM152(seeFIG. 37).

The communication circuit155receives the ID number of a member who is newly registered and the ID number of a member who is deleted because withdrawal from membership from the server, for example, every time when a game is started, and then updates the data stored in the member ID storage area52D.

Next, with reference toFIG. 38, the game mode switching process at S1inFIG. 10of the slot machine150will be described.

In the embodiment, prior to S11in the game mode switching process of the first embodiment (seeFIG. 11), it is determined whether the member card151is inserted into the card insertion slot156(S301) and member identification is performed (S302). At S301, determination is made based on whether or not to receive the card detection signal from the card sensor153. When it is determined that the member card151is inserted (S301: YES), the CPU50references to data on the member card151which is read by the card reader154and to the member ID storage area52D in the RAM52, and determines whether a player is a member (S302). When the member ID number recorded on the member card151is stored in the member ID storage area52D in the RAM52, it is determined that the player is a member.

When it is determined that the member card151is not inserted into the card insertion slot156(S301: NO) or it is determined that the player is not a member (S302: NO), the game mode switching process is ended. Then, the process is returned to the main process to move to the starting process (S2) inFIG. 10. In this case, in order to avoid permitting a non-member player to play games in the insured modes the game mode is switched to the uninsured mode if it is set in the insured mode. Thus, the following can be avoided: a member player plays games on a slot machine150and finishes a game in the insured mode remained, and another player who is not a member subsequently plays games on the gaming machine150in the insured mode.

When it is determined that the player is a member (S302: YES), the process is moved to S303. S303to S309are the same as S11to S17inFIG. 11, omitting the description.

As described above, according to the slot machine150of the embodiment, since only the player who is a member of the game shop can make selection of the insured mode or the uninsured mode, services for members can be improved. Besides, willingness for member registration can be provoked to nonmember players.

Next, with reference toFIGS. 39,40, and41, an embodiment of a game system of the invention will be described. Hereinafter, the same components as those described in the embodiments described above are assigned the same numeral and signs, omitting the description.

A game system200of the embodiment includes slot machines250and a server201that is connected in communication with the slot machines250via a network210. The network210may be LAN (Local Area Network), WAN (Wide Area Network), a dedicated communication network, the Internet, or the like. The server201and the slot machines250may be placed in the same game shop.

The slot machine250having a communication circuit155has substantially the same configuration as that of the slot machine150of the fifth embodiment described above, but is different from the slot machine150in that RAM does not have the member ID storage area52D. In the fifth embodiment, the RAM152of the slot machine150has the member ID storage area52D, and the CPU50of the slot machine150performs member identification. However, in the embodiment, the server201having a member information DB206which stores the ID numbers of all the members of the game shop performs the member identification.

A control unit of the server201is configured as a CPU203is centered. The CPU203is connected to ROM204and RAM205. The ROM204stores a member identification program (seeFIG. 41) which is described below, various programs necessary to control the server201, data tables, and the like. The RAM205is a memory for temporarily storing various data computed by the CPU203.

The server201further has the member information DB206and a communication circuit207. The communication circuit207communicates with each of the slot machines250to receive the member ID number sent from a communication circuit155of the slot machine250. The CPU203references to the member ID number received by the communication circuit207and the member information DB206for member identification. The identification result is sent to the corresponding slot machine250via the communication circuit207.

Next, with reference toFIG. 40, the game mode switching process (S1inFIG. 10) in the slot machine250will be described.

At S401, as similar to S301inFIG. 38, the CPU203determines whether the member card151is inserted into the card insertion slot156. When it is determined that the member card151is inserted (S401: YES), the CPU203sends the member ID number read by the card reader154to the server201via the communication circuit155(S402).

At S403, the communication circuit155receives the result of member identification by the server201, details of which is described below, (seeFIG. 41). Then, based on the result, it is determined whether a player is a member (S404).

When it is determined that the member card151is not inserted into the card insertion slot156(S401: NO) or it is determined that the player is not a member (S404: NO), the game mode switching process is ended to return to the starting process (S2) of the main process shown inFIG. 10. However in this case, as similar to the slot machine150described above, in order to avoid permitting a non-member player to play games in the insured mode, the game mode is switched to the uninsured mode when it is set in the insured mode.

When the player is identified as a member (S404: YES), the process is moved to S405. S405to S411are the same as S11to S17inFIG. 11, respectively, omitting the description.

Next, with reference toFIG. 41, member identification performed in the server201of the game system200will be described.

First, at S421, it is determined whether the member ID number, which is sent from the slot machine250at S402(seeFIG. 40), is received. When it is determined that the member ID number is not received (S421: NO), wait until it is sent. When it is determined that the member ID number is received (S421: YES), the process is moved to S422.

At S422; it is determined whether the received number is matched with any one of the numbers stored in the member information DB206. When it is determined that the received number is matched with one of the numbers stored in the member information DB206(S422: YES), the identification result indicating that the player is a member is sent to the slot machine250(S423). When it is determined that the received number is not matched with any one of the numbers stored in the member information DB206(S422: NO), the identification result indicating that the player is not a member is sent to the slot machine250(S424).

As described above, according to the game system200of the embodiment, as similar to the first to fourth embodiments, a player can select whether or not to apply the compensation function by his/her intention through the INSURE ON/OFF button13on the slot machine250. Thus, player's satisfaction can be increased.

Furthermore, as similar to the fifth embodiment, since only a member player of the game shop can make selection of the insured mode or the uninsured mode, services for members can be improved. Besides, willingness for member registration can be provoked to non-member players.

The slot machines250may be grouped to provide the server201for each group.

At S83(seeFIG. 17), a receipt on which the amount of coins to be paid out is written may be ejected instead of payout of coins. In this case, the receipt may be exchanged with a prize at, for example, a counter in the game shop.

The number of credits collected as an insurance fee at S27in the first embodiment (seeFIG. 12) is not limited to one credit. For example, it may be two credits or five credits. Furthermore, the rate for collecting an insurance fee in the example inFIG. 19is not limited to 3%.

Credits may be paid out when the payout rate is equal to or less than a predetermined rate, for example, not when the amount of lost credits reaches the upper limit. In this case, the payout rate may be displayed on the insurance indicator11.

Lost credit data is initialized at S84inFIG. 17in accordance with pressing the COLLECT button31, but which is not limited thereto. For example, an infrared sensor may be placed on the front of the slot machines1,150and250to detect that the player is gone i.e., the change of player, so that the lost credit data is initialized.

In the bonus game and the mystery bonus game, instead of free games, a selective game may be played that moves by selecting options displayed on the display3or4.

The gaming machine according to the invention is not limited to the slot machine using the video reels21to25, which can be applied to gaming machines such as a slot machine using mechanical reels, a pachi-slot machine, and a pachinko machine other than the slot machine.