Abstract:
A gaming machine includes an effect display device for displaying either an effect or a first game thereon, a variable display device arranged behind the effect display device, a game controller for executing the first game utilizing the effect display device and a second game utilizing the variable display device and a display controller for controlling light transmittance of the effect display device so that the variable display device is selectively seen and recognized through the effect display device. The display controller alternatively executes the effect and displays the first game when the game controller determines to alternatively conduct the effect and display the first game while simultaneously concealing the variable display device or the display controller alternatively executes the effect and the second game when the game controller determines to alternatively conduct the effect and display the second game while simultaneously prohibiting display of the first game.

Description:
CROSS-REFERENCE TO THE RELATED APPLICATION (S) 
   This application is based upon and claims a priority from the prior Japanese Patent Application No. 2003-306489 filed on Aug. 29, 2003, the entire contents of which are incorporated herein by reference. This application is related to co-pending U.S. patent application entitled to “GAMING MACHINE”, which is based upon and claims a priority from the prior Japanese Patent Application No. 2003-306000, which was filed on Aug. 29, 2003 and the inventor of which is Masatsugu KOBAYASHI. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a gaming machine which has an effect display device and a variable display device arranged behind the effect display device. 
   2. Description of Related Art 
   The conventional gaming machine, for example, a slot machine, is constructed so that medals and the like are paid out corresponding to a predetermined symbol combination when symbols variably displayed are stopped and displayed on a pay line with the predetermined symbol combination. Here, in many cases, the symbols, which are variably displayed, are formed on an outer periphery of a reel rotatably supported in the gaming machine, as shown, for example, in Japanese Unexamined Publication No. 2001-347042. And recently, there are many cases that the symbols are projected on a display plane of a liquid crystal display device adopted in a so-called video slot machine. 
   Considering the above situation, it will be conceivable a gaming machine that both the liquid crystal display and the reels are provided in the same gaming machine. Thereby, a player can continuously enjoy different games by shifting the game done on the liquid crystal display device to the game done on the reels or the game done on the reels to the game done on the liquid crystal display device. 
   However, in a case that both the liquid crystal display device and the reels are arranged in the gaming machine in a state that the player can always see those, the player can easily infer contents and progress of the game, therefore interest for games is reduced. 
   SUMMARY OF THE INVENTION 
   The present invention has been done to dissolve the above problems and has an object to provide a gaming machine in which a first game utilizing an effect display device such as a liquid crystal display device and a second game utilizing a variable display device such as reels are executed, and interest for the second game done on the variable display device can be highly maintained by contriving a display mode that the variable display device arranged behind the liquid crystal display device is able to be recognized. 
   According to one aspect of the present invention, it is provided a gaming machine comprising: 
   an effect display device for displaying an effect thereon; 
   a variable display device arranged behind the effect display device; 
   a game controller for executing a first game utilizing the effect display device and a second game utilizing the variable display device; 
   a display controller for controlling light transmittance of the effect display device so that the variable display device is seen and recognized through the effect display device; 
   wherein the display controller executes the effect while the first game is executed by controlling the light transmittance of the effect display device when the game controller determines to conduct the effect by utilizing the display controller and conceals the variable display device except for a case that the game controller determines to conduct the effect by utilizing the display controller or a case that the second game is executed. 
   According to the gaming machine, the display controller executes the effect while the first game is executed by controlling the light transmittance of the effect display device when the game controller determines to conduct the effect by utilizing the display controller and conceals the variable display device except for a case that the game controller determines to conduct the effect by utilizing the display controller or a case that the second game is executed. Therefore, interest for the second game can be highly raised and variegated effect can be done. 
   The above and further objects and novel features of the invention will more fully appear from the following detailed description when the same is read in connection with the accompanying drawings. It is to be expressly understood, however, that the drawings are for purpose of illustration only and not intended as a definition of the limits of the invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are incorporated in and constitute a part of this specification illustrate embodiments of the invention and, together with the description, serve to explain the objects, advantages and principles of the invention. 
     In the drawings, 
       FIG. 1  is a perspective view showing a slot machine, 
       FIG. 2  is a longitudinal sectional view of a lower liquid crystal display and a reel, 
       FIG. 3  is an exploded perspective view of the lower liquid crystal display, 
       FIG. 4  is a block diagram schematically showing a control system of the slot machine, 
       FIG. 5  is a block diagram schematically showing a liquid crystal drive circuit of the lower liquid crystal display, 
       FIG. 6  is an explanatory view showing symbol rows variably displayed on variable display portions which are displayed on the lower liquid crystal display when a base game is conducted, 
       FIG. 7  is an explanatory view showing symbol rows formed on the reels, the symbol rows being utilized in a free game and seen and recognized through the variable display portions on the lower liquid crystal display, 
       FIGS. 8A ,  8 B and  8 C are explanatory views showing lottery tables based on which the symbols to be stopped and displayed on three variable display portions are determined when the base game is conducted while utilizing three variable display portions, 
       FIG. 9  is an explanatory view showing correspondence between winning combinations and payouts when the base game is conducted while utilizing three variable display portions, 
       FIGS. 10A ,  10 B and  10 C are explanatory views showing lottery tables based on which the symbols stopped and displayed on the reels, the symbols being seen and recognized through the variable display portions, are determined when the free game is conducted while utilizing three variable display portions and reels, 
       FIG. 11  is an explanatory view showing correspondence between winning combinations and payouts when the free game is conducted while utilizing three variable display portions and reels, 
       FIGS. 12A and 12B  are explanatory views showing payout expectation values in the base game, 
       FIGS. 13A and 13B  are explanatory views showing payout expectation values in the free game, 
       FIG. 14  is a flowchart showing a main process program, 
       FIG. 15  is a flowchart showing a start acceptance process program, 
       FIG. 16  is a flowchart showing a lottery process program, 
       FIG. 17  is a flowchart showing a base game process program, 
       FIG. 18  is a flowchart showing a free game process program, 
       FIG. 19  is an explanatory view showing a lottery table for a shift effect process when the free game is executed by utilizing three variable display portions, 
       FIG. 20  is an explanatory view showing symbols shown on the lower liquid crystal display when a joker is won, in case that the base game is executed by utilizing three variable display portions, 
       FIG. 21  is an explanatory view showing symbols which are variably displayed while scrolled on the lower liquid crystal display, in a case that the base game is executed by utilizing three variable display portions, 
       FIGS. 22A ,  22 B,  22 C and  22 D are explanatory views showing display contents sequentially displayed on the lower liquid crystal display, in a case that the base game is executed by utilizing three variable display portions, 
       FIGS. 23A ,  23 B,  23 C and  23 D are explanatory views showing display contents sequentially displayed on the lower liquid crystal display, in a case that the base game is executed by utilizing three variable display portions, 
       FIGS. 24A ,  24 B,  24 C and  24 D are explanatory views showing display contents sequentially displayed on the lower liquid crystal display, in a case that the base game is executed by utilizing three variable display portions, 
       FIG. 25  is a flowchart showing the lottery process program, 
       FIG. 26  is a flowchart showing a rotation process program, 
       FIG. 27  is an explanatory view of a lottery table showing correspondence between winning combinations and payouts when the base game is conducted while utilizing three variable display portions, and 
       FIG. 28  is an explanatory view of a lottery table showing correspondence between winning combinations and payouts when the free game is conducted while utilizing three variable display portions and reels. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Hereinafter, as the gaming machine according to the present invention, the embodiment embodying the present invention in the slot machine will be described with reference to the drawings. First, an outline construction of the slot machine according to the embodiment will described with reference to  FIGS. 1 and 4 .  FIG. 1  is a perspective view of the slot machine.  FIG. 4  is a block diagram schematically showing a control system in the slot machine 
   In  FIG. 1 , the slot machine  1  has a cabinet  2  constructing a whole of the slot machine  1 . At a front upper part of the cabinet  2  an upper liquid crystal display  3  is arranged, and at a front central part of the cabinet  2  a lower liquid crystal display  4  is arranged. Here, the upper liquid crystal display  3  is constructed from a liquid crystal display device which is generally used, and the lower liquid crystal display  4  is constructed from, so-called, a transparent liquid crystal display device. On the upper liquid crystal display  3 , game operation method, kinds of winning combinations and payout therefor and information concerning with the game such as various effects thereof are displayed. And on the lower liquid crystal display  4 , as shown in  FIG. 1 , three variable display portions  22 ,  23  and  24  are basically displayed and various symbols (mentioned later) are scrolled to the downward direction from the upward direction while being variably displayed on each of the variable display portions  22  to  24 . Here, the detailed construction of the lower liquid crystal display  4  will be described hereinafter. 
   A control panel  5 , which is projected frontward, is formed below the lower liquid crystal display  4 , and from the most left side on the control panel  5 , a change button  6 , a payout (cashout) button  7 , a help button  8  are arranged. And a coin insertion slot  9  and a bill insertion portion  10  are arranged at the right side of help button  8 . Further, from the left side, a 1-BET button  11 , a SPIN/REPEAT BET button  12 , a 3-BET button  13  and a 5-BET button  14  are positioned at the front side on the control panel  5 . 
   Here, the change button  6  is pressed when exchanging the bill inserted in the bill insertion portion  10 , and the exchanged coins are paid out through a coin payout chute  15  to a coin tray  16  which is formed at the lower part of the cabinet  2 . To the change button  6 , a change switch  62  (explained hereinafter) is attached, and a switch signal is output to a CPU  50  from the change switch  62  based on press of the change button  6 . 
   The payout button  7  is usually pressed when games are terminated, and when the payout button  7  is pressed coins got in games are paid out through the coin payout chute  15  to the coin tray  16 . Here, to the payout button  7 , a payout (cashout) switch  63  (mentioned hereinafter) is attached and a switch signal is output to the CPU  50  from the payout switch  63  based on press of the payout button  7 . 
   The help button  8  is pressed when the player cannot understand game operation method, and when the help button  8  is pressed, various help information is displayed on the upper liquid crystal display  3  or the lower liquid crystal display  4 . To this help button  8 , a help switch  64  (mentioned hereinafter) is attached and a switch signal is output to the CPU  50  from the help switch  64  based on press of the help button  8 . 
   To the coin insertion slot  9 , a coin sensor  65  (mentioned hereinafter) is positioned, and when the coin is inserted in the coin insertion slot  9  a coin detection signal is output to the CPU  50  through the coin sensor  65 . And to the bill insertion portion  10  a bill sensor  66  (mentioned hereinafter) is positioned, and when the bill is inserted in the bill insertion portion  10  a bill detection signal is output to the CPU  50  through the bill sensor  66 . 
   As for the 1-BET button  11 , every the 1-BET button is pressed one credit is betted, and to the 1-BET button  11 , a 1-BET switch  59  is attached and when the 1-BET button  11  is pressed a switch signal is output to the CPU  50  from the 1-BET switch  59  based on press of the 1-BET button  11 . 
   The SPIN/REPEAT BET button  12  is the button to start games from the present bet number or the previous bet number by press thereof, thereby variable display of the symbols is started on the variable display portions  21  to  25  of the lower liquid crystal display  4 . To the SPIN/REPEAT BET button  12 , a spin switch  58  (mentioned later) is attached, and when the SPIN/REPEAT BET button  12  is pressed a switch signal is output to the CPU  50  from the spin switch  58  based on press of the SPIN/REPEAT BET button  12 . Here, as the bet number which can be betted by press of the SPIN/REPEAT BET button  12 , there may exist 1, 2, 3 and 5 bets. 
   The 3-BET button  13  is the button to start games from 3 bets on the basis of press thereof. To this 3-BET button  13 , a 3-BET switch  60  (mentioned hereinafter) is attached and when the 3-BET button  13  is pressed a switch signal is output to the CPU  50  from the 3-BET switch  60 . And the 5-BET button  14  is the button to start games from 5 bets on the basis of press thereof. To the 5-BET button  12 , a 5-BET switch  61  is attached and when the 5-BET button is pressed a switch signal is output to the CPU  50  from the 5-BET switch  61  on the basis of press thereof. 
   Further, at the lower part of the cabinet  2 , the coin payout chute  15  is formed and the coin tray  16  to receive coins paid out from the coin payout chute  15  is provided. In the coin payout chute  15 , a coin detection part  73  constructed from a sensor and the like is positioned and the coin detection part  73  detects the number of coins paid out from the coin payout chute  15 . 
   At the most front side of the control panel  5 , stop buttons  27  to  29  are provided corresponding to each of the variable display portions  22  to  24 , respectively. Here, as mentioned hereinafter, although these stop buttons are pressed when the symbols, which are scrolled on the variable display portions, are stopped and displayed thereon, the symbols cannot be stopped at timing of the press operation of the stop buttons  27  to  29 . The switch signal output from the stop button switch  67  based on press of each of the stop buttons  27  to  29  is utilized to the end only as a trigger when the symbols scrolled on the variable display portions are stopped and displayed. 
   Further, at the side plane (the right side plane in  FIG. 1 ) of the cabinet  2 , a start lever  17  is arranged rotatably within a predetermined angle range. To the start lever  17 . a start switch  57  (mentioned hereinafter) is attached and when the start lever  17  is rotated a switch signal occurring from the start switch  57  is output to the CPU  50 . 
   Next, it will be described a detailed construction of the lower liquid crystal display  4  and reels rotatably arranged behind the lower liquid crystal display  4  in the cabinet  2 , with reference to  FIGS. 2 and 3 .  FIG. 2  is a longitudinal sectional view of the lower liquid crystal display and the reels, and  FIG. 3  is an exploded perspective view of the lower liquid crystal display  4 . 
   In  FIGS. 2 and 3 , the lower liquid crystal display  4  is arranged within a display window  21  of a device front panel  20  positioned at the front center part of the cabinet  2  in the slot machine  1 , with a touch panel  30  arranged at the front side (the left side in  FIG. 2 ) of the lower liquid crystal display  4 . And at the rear side (the right side in  FIG. 2 ) of the lower liquid crystal display  4 , three reels  220  (only one reel  220  is indicated in  FIG. 2 ) are supported in a parallel state so that the reels  220  become independently rotatable. 
   That is to say, as shown in  FIG. 2 , the lower liquid crystal display  4  is arranged in front of three reels  220 . And a base game mentioned later is conducted on the lower liquid crystal display  4  and a free game mentioned later is conducted on the reels  220 . 
   Here, each reel  220  will be described. Among three reels  220 , the left reel  220  when seen from the front plane of the slot machine  1  faces to a display portion  22  (see  FIG. 1 ) formed in the lower liquid crystal display  4 , the center reel  220  faces to a display portion  23  (see  FIG. 1 ) similarly formed in the lower liquid crystal display  4  and the right reel  220  faces to a display portion  24  (see  FIG. 1 ) similarly formed in the lower liquid crystal display  4 . 
   Here, construction of each of the variable display portions  22  to  24  win be described hereinafter. 
   Further, on an outer periphery of each reel  220 , various kinds of symbols shown in  FIG. 7  (three kinds of symbols are indicated in  FIG. 7 ) are formed, such symbols being used in a free game explained hereinafter. Concretely, as kinds of symbols formed on the outer periphery of the reel  220 , a seven symbol  191 , a triple symbol  192  and a double symbol  193  are utilized. And these three kinds of symbols and blanks  194  (area that no symbol exists) are combined based on predetermined combinations and on an outer periphery of each reel  220 , the combination of the symbols, in which the symbols and the blanks are totally combined (the total number of the symbols and the blanks is 12) is formed. 
   Here, various winning combinations are determined beforehand based on plural kinds of combinations of the symbols and when the symbol combination corresponding to the winning combination is stopped along a pay line L (see  FIG. 1 ), coins are paid out from the coin payout chute  15  according to the winning combination. These points are as same as that in the conventional slot machine, therefore explanation thereof will be omitted. And formation of the symbols on the outer periphery of the reel  220  is generally done as follows. First, symbols and blanks (total number of which is 12) are printed on a long reel sheet having a width and a length corresponding to the width and the periphery length of the reel  220 , respectively. And such reel sheet is adhered on the peripheral plane of the reel  220 . Of course, the symbols may be formed by different method other than the above method. 
   Next, construction of the lower liquid crystal display  4  will be described with reference to FIGS.  2  and  3 A˜ 3 I. In FIGS.  2  and  3 A˜ 3 I, the lower liquid crystal display  4  is constructed by arranging from the front side of the slot machine  1 ; the transparent touch panel  30 , the reel glass base  31 , the bezel metal frame  32 , the transparent liquid crystal panel  33 , the liquid crystal holder  34 , the diffusion sheet  35 , the light guiding plate  36 , the white reflector  37 , the rear holder  38  and the antistatic sheet  39 . In the diffusion sheet  35 , three openings  35 A,  35 B,  35 C are formed. Similarly, in the light guiding plate  36 , the reflector  37  and the rear holder  38 , three openings  36 A,  36 B,  36 C,  37 A,  37 B,  37 C,  38 A,  38 B,  38 C are formed respectively, so as to coincide with the openings  35 A,  35 B,  35 C. Here, the openings  35 A˜ 38 A construct the variable display portion  22  (see  FIG. 1 ) by superimposing so as to coincide with each other. Similarly, the openings  35 B˜ 38 B construct the variable display portion  23  (see  FIG. 1 ) by superimposing so as to coincide with each other and the openings  35 C˜ 38 C construct the variable display portion  24  (see  FIG. 1 ) by superimposing so as to coincide with each other. 
   Here, the openings  35 A˜ 35 C of the diffusion sheet  35  and the openings  36 A˜ 36 C of the light guiding plate  36  construct the light transmitting areas to retain visibility of the variable display portions  22  to  24 . 
   In order to install the lower liquid crystal display  4  to the display window  210  of the device front panel  20 , as shown in  FIG. 2 , brackets  40  are screwed to the rear side of the device front panel  20  by screws  410 . 
   And at an upper and lower ends of the light guiding plate  36 , a pair of cathode ray tubes  420  are arranged as light source of the liquid crystal panel  33 . And at an upper and lower positions in the rear side of each of openings  38 A˜ 38 C in the holder  38 , a pair of cold cathode ray tubes  430  may be arranged. 
   The liquid crystal panel  33  is a transparent electric display panel on which transparent electrodes such as Ito are formed, and the circumference in rear side of the display portion of the liquid crystal panel  33  is held by the liquid crystal holder  34 . The light guiding plate  36  is made of the light transmitting resin panel, and in the light guiding plate  36  lens cut portions are formed, the lens cut portions guiding light emitted from the cathode ray tubes  420  positioned at side positions to the rear side of the liquid crystal panel  33 . The light diffusion sheet  35  is made from a light transmitting resin sheet and diffuses light led thereto by the light guiding plate  36  and levels light irradiated to the liquid crystal panel  33 . The liquid crystal holder  34  for holding the liquid crystal panel  33 , the diffusion sheet  35  and the light guiding plate  36  are assembled into one-piece construction and circumference thereof is inserted in the bezel metal frame  32 . Thereby, the front side of the display portion in the liquid crystal panel  33  is retained by the bezel metal frame  32 . 
   Circumferences of the liquid crystal holder  34 , the light diffusion sheet  35  and the light guiding plate  36 , which are inserted in the bezel metal frame  32  and assembled into one-piece construction, is further inserted in the reel glass base  31  and retained by the reel glass base  31  in a state that the front display plane of the liquid crystal panel  33  is opened. The transparent touch panel  30  is pressed to the front face of the reel glass base  31  and superimposed on the front face of display portion of the liquid crystal panel  33  based on that the reel glass base  31  is attached to the device front panel  20  by screws  410 . 
   The rear holder  38  is made from a white resin plate and retains to the reel glass base  31  the bezel metal frame  32  supported to the reel glass base  31 , the liquid crystal holder  34  holding the liquid crystal panel  33 , the light diffusion sheet  35  and the light guiding plate  36  from the rear sides thereof. The rear holder  38  also functions as a reflecting plate for reflecting light emitted from the cathode ray tubes  420  to the light guiding plate  36  toward the liquid crystal panel  33 . The antistatic sheet  39  is made transparent and adhered to the rear plane of the rear holder  38  by double-sided adhesive tape, thereby the antistatic sheet  39  covers the rear plane of each of the openings  38 A˜ 38 C formed in the rear holder  38 . 
   Next, according to  FIG. 6 , it will be described symbol rows which are variably displayed on the variable display portions  22  to  24  of the lower liquid crystal display  4  while scrolling thereon, the symbol rows being displayed on the lower liquid crystal display  4  in the base game. In  FIG. 6 , the symbol row  41  is the symbol row which is variably displayed on the variable display portion  22 , the symbol row  42  is the symbol row which is variably displayed on the variable display portion  23 , the symbol row  43  is the symbol row which is variably displayed on the variable display portion  24 . 
   Here, the symbol rows  41  and  43  commonly have the same arrangement of the symbols and such arrangement of the symbols is constructed from eleven symbols in which the triple BAR  91 , the cherry  92 , the double BAR  93 , the symbol seven  94 , the single BAR  95  and the blank (no symbol exists)  96  are voluntarily combined. 
   And although the symbol row  42  is as same as the symbol row  41  and  43  at the point that the triple BAR  91 , the cherry  92 , the double BAR  93 , the symbol seven  94 , the single Bar  95  and the blank  96  are combined, one joker  97  as the trigger symbol is further arranged in the symbol row  42 . This trigger symbol  97 , as mentioned hereinafter, functions as a symbol to shift to the free game in the base game, and when the trigger symbol  97  is stopped and displayed on the pay line L in the variable display portion  23 , the game condition shifts to the free game from the base game. 
   Here, when the symbol rows  41  to  43 , which are scrolled on the variable display portions  22  to  24  respectively, are stopped and displayed thereon, three symbols are stopped and displayed on each variable display portion. 
   And various winning combinations are set beforehand based on a plurality of symbol combinations and when the symbol combination corresponding to the winning combination is stopped on the pay line L, coins are paid out from the coin payout chute  15  according to the winning combination. The above mentioned points are as same as those in the conventional slot machine, therefore detailed description thereof will be omitted. 
   Next, it will be described a construction of the control system in the slot machine  1  with reference to  FIG. 4 .  FIG. 4  is a block diagram schematically showing the control system in the slot machine  1 . 
   In  FIG. 4 , the control system of the slot machine  1  is basically constructed from the CPU  50 , and a ROM  51  and a RAM  52  are connected to the CPU  50 . The ROM  51  stores a main process program mentioned later, a base game process program, a free game process program, various effect programs for executing various effects on the upper liquid crystal display  3  and the lower liquid crystal display  4  according to progress in games, a lottery table utilized in lottery of the symbols stopped and displayed in the base game, a lottery table utilized in lottery of the symbols stopped and displayed in the free game, various programs necessary for controlling the slot machine  1  and various data tables and the like. And the RAM  52  is a memory for temporarily storing various data calculated by the CPU  50 . 
   And to the CPU  50 , a clock pulse generator  53  for generating standard clock pulses and a frequency divider  54  are connected, and a random number generator  55  and a sampling circuit  56  are also connected. Random number sampled by the random number generator  56  is utilized in various lotteries of the winning combinations, the effects and the like. Further, to the CPU  50 , the start switch  57  attached to the start lever  17 , the spin switch  58  attached to the SPIN/REPEAT BET button  12 , the 1-BET switch  59  attached to the 1-BET button  11 , the 3-BET switch  60  attached to the 3-BET button  13 , the 5-BET switch  61  attached to the 5-BET button  14 , the change switch  62  attached to the change button  6 , the payout switch  63  attached to the payout button  7  and the help switch  64  attached to the help button  8  are connected respectively. The CPU  50  controls the slot machine  1  to execute various operations corresponding to each button, based on the switch signal output from each switch when such buttons are pressed. 
   To the CPU  50 , three stepping motors  68  for rotating each of the reels  220  through a motor drive circuit  167  are connected, and also a reel position detection circuit  69  is connected. When a motor drive signal is output to the motor drive circuit  167 , each stepping motor  68  is driven to rotate by the motor drive circuit  167 , thereby each reel  220  is rotated. 
   At that time, after each reel  22  is started to rotate, the number of drive pulses provided to each stepping motor  68  is calculated and the calculated value is written in the predetermined area of the RAM  52 . And the reset pulse is output every one rotation of the reel  220  and such reset pulse is input to the CPU  50  through the reel position detection circuit  69 . When the reset pulse is input to the CPU  50 , the calculated value written in the RAM  52  is cleared in “0”, and the CPU  50  recognizes the symbol rotational position in the reel  220 , based on the calculated value corresponding to the rotational position of the reel  220  within one rotation and the symbol table in which the rotational position of the reel  22  stored in the ROM  51  and the symbols formed on outer peripheral plane of the reel  22  are corresponded with each other. 
   Further, to the CPU  50 , the coin sensor  65  positioned in the coin insertion slot  9  and the bill sensor  66  positioned in the bill insertion portion  10  are connected respectively. The coin sensor  65  detects coins inserted from the coin insertion slot  9  and the CPU  50  calculates the number of inserted coins based on the coin detection signal output from the coin sensor  65 . The bill sensor  66  detects the kind and sum of bill and the CPU  50  calculates the number of coins equivalent to sum of bill, based on the bill detection signal output from the bill sensor  66 . And to the CPU  50 , the stop button switches  67  attached to the stop buttons  27  to  29  are connected. When press operation of the stop buttons  27  to  29  is conducted, switch signals are output from the stop button switches  67  and the CPU  50  stops and displays the symbols which are scrolled on the variable display portions  22  to  24 , based on switch signals. 
   To the CPU  50 , a hopper  71  is connected through a hopper drive circuit  70 . When a drive signal is output to the hopper circuit  70  from the CPU  50 , the hopper  71  pays out predetermined number of coins from the coin payout chute  15   
   And to the CPU  50 , a coin detection part  73  is connected through a payout completion signal circuit  72 . The coin detection part  73  is arranged in the coin payout chute  15  and when the coin detection part  73  detects that a predetermined number of coins are paid out from the coin payout chute  15 , the payout completion signal is output to the payout completion signal circuit  72  from the coin detection part  73 . Based on this, the payout completion signal circuit  72  outputs the payout completion signal to the CPU  50 . Further, to the CPU  50 , the upper liquid crystal display  3  is connected through a liquid crystal drive circuit  74  and the lower liquid crystal display  4  is connected through a liquid crystal drive circuit  75 . The upper liquid crystal display  3  and the lower liquid crystal display  4  are controlled by the CPU  50 . 
   At this point of view, as shown in  FIG. 5 , the liquid crystal drive circuit  74  is constructed from a program ROM  81 , an image ROM  82 , an image control CPU  83 , a work RAM  84 , a VDP (Video Display Processor)  85  and a video RAM  86 . And in the program ROM  81 , an image control program concerning with display on the lower liquid crystal display  4  and various selection tables are stored. Further, in the image ROM  82 , for example, it is stored dot data for forming images such as the symbol rows  41 ˜ 43  in  FIG. 6  displayed on the lower liquid crystal display  4  (or variable display portions  22  to  24 ). And the image control CPU  83  determines images displayed on the lower liquid crystal display  4  among the dot data stored in the image ROM  82  beforehand, according to the image control program stored in the program ROM  81  based on parameters set by the CPU  50 . And the work RAM  84  functions as the temporary memory when the above image control program is executed by the image control CPU  83 . Further, the VDP  85  forms images corresponding to display contents determined by the image control CPU  83  and outputs the images to the lower liquid crystal display  4 . Thereby, for example, the symbol rows  41 ˜ 43  of  FIG. 6  are scrolled and displayed on the lower liquid crystal display  4  (or variable display portions  22  to  24 ). Here, the video RAM  86  functions as the temporary memory when images are formed by the VDP  85 . 
   And to the CPU  50 , LEDs  78  are connected through a LED drive circuit  77 . A plurality of LEDs  78  are arranged on the front plane of the slot machine  1  and the LEDs  78  are controlled so as to turn on based on the drive signals from the CPU  50 . Further, a speaker  80  and a sound output circuit  79  are connected to the CPU  50  and the speaker  80  produces various effective sounds when various effects are conducted based on the output signal from the sound output circuit  79 . 
   Here, in a case that the base games are conducted in the slot machine  1  by utilizing three variable display portions  22  to  24 , the lottery table utilized when the symbols stopped and displayed on the pay line L are determined will be described with reference to  FIG. 8 .  FIG. 8  is an explanatory view showing the lottery table based on which the symbols to be stopped and displayed on three variable display portions  22  to  24  are determined when the base game is conducted while utilizing three variable display portions  22  to  24 . 
   The symbols stopped and displayed on the pay line L are determined every the variable display portion  22  to  24 . In order to realize this, one of the code numbers “0”˜“10” is allotted to each symbol in the symbol rows  41  to  43  shown in  FIG. 6  which are displayed on the variable display portions  22  to  24 , respectively, and it is provided the lottery table shown in  FIG. 8 . Further, three random number values are sampled corresponding to each of the variable display portions  22  to  24 , through the random number sampling circuit  56 . 
   Here, in  FIG. 8 , for explanatory convenience, the symbol row  41  of the left variable display portion  22  is indicated as the “left reel”, the symbol row  43  of the right variable display portion  24  is indicated as the “right” reel and the symbol row  42  of the center variable display portion  23  is indicated as the “center reel”. 
   As for the “left reel” corresponding to the symbol row  41  of the left variable display portion  22 , if the random number value sampled by the random number sampling circuit  56  lies in a range of 0˜15, the blank  96  allotted to the code number “0” is stopped and displayed on the pay line L. And if the random number value lies in a range of 16˜25, the triple BAR  91  allotted to the code number “1” is stopped and displayed on the pay line L, and if the random number value lies in a range of 26˜36, the cherry  92  allotted to the code number “2” is stopped and displayed on the pay line L. If the random number value lies in a range of 37˜46, the double BAR  93  allotted to the code number “3” is stopped and displayed on the pay line L, and if the random number value lies in a range of 47˜52, the symbol seven  94  allotted to the code number “4” is stopped and displayed on the pay line L. If the random number value lies in a range of 53˜63, the single BAR  95  allotted to the code number “5” is stopped and displayed on the pay line L, and if the random number value lies in range of 64˜80, the blank  96  allotted to the code number “6” is stopped and displayed on the pay line L. If the random number value lies in a range of 81˜91, the triple BAR allotted to the code number “7” is stopped and displayed on the pay line L, and if the random number value lies in a range of 92˜103, the double BAR  93  allotted to the code number “8” is stopped and displayed on the pay line L. If the random number value lies in a range of 104˜115, the symbol seven  94  allotted to the code number “9” is stopped and displayed on the pay line L, and if the random number value lies in a range of 116˜127, the single BAR  95  allotted to the code number “10” is stopped and displayed on the pay line L. 
   And as for the “right reel” corresponding to the symbol row  43  of the right variable display portion  24 , there is the same relation as that in the above left reel. And if the random number value sampled by the random number sampling circuit  56  lies in a range of 0˜15, the blank  96  allotted to the code number “0” is stopped and displayed on the pay line L. And if the random number value lies in a range of 16˜25, the triple BAR  91  allotted to the code number “1” is stopped and displayed on the pay line L, and if the random number value lies in a range of 26˜36, the cherry  92  allotted to the code number “2” is stopped and displayed on the pay line L. If the random number value lies in a range of 37˜46, the double BAR  93  allotted to the code number “3” is stopped and displayed on the pay line L, and if the random number value lies in a range of 47˜52, the symbol seven  94  allotted to the code number “4” is stopped and displayed on the pay line L. If the random number value lies in a range of 53˜63, the single BAR  95  allotted to the code number “5” is stopped and displayed on the pay line L, and if the random number value lies in range of 64˜80, the blank  96  allotted to the code number “6” is stopped and displayed on the pay line L. If the random number value lies in a range of 81˜91, the triple BAR allotted to the code number “7” is stopped and displayed on the pay line L, and if the random number value lies in a range of 92˜103, the double BAR  93  allotted to the code number “8” is stopped and displayed on the pay line L. If the random number value lies in a range of 104˜115, the symbol seven  94  allotted to the code number “9” is stopped and displayed on the pay line L, and if the random number value lies in a range of 116˜127, the single BAR  95  allotted to the code number “10” is stopped and displayed on the pay line L. 
   On the other hand, as for the “center reel” corresponding to corresponding to the symbol row  42  of the center variable display portion  23 , if the random number value sampled by the random number sampling circuit  56  is 0 (zero), the trigger symbol  97  allotted to the code number “0” is stopped and displayed on the pay line L. And if the random number value lies in a range of 1˜15, the triple BAR  91  allotted to the code number “1” is stopped and displayed on the pay line L, and if the random number value lies in a range of 16˜20, the cherry  92  allotted to the code number “2” is stopped and displayed on the pay line L. And if the random number value lies in a range of 21˜32, the double BAR  93  allotted to the code number “3” is stopped and displayed on the pay line L, and if the random number value lies in a range of 33˜45, the symbol seven  94  allotted to the code number “4” is stopped and displayed on the pay line L. And if the random number value lies in a range of 46˜53, the single BAR  95  allotted to the code number “5” is stopped and displayed on the pay line L, and if the random number value lies in a range of 54˜64, the blank  96  allotted to the code number “6” is stopped and displayed on the pay line L. And if the random number value lies in a range of 65˜71, the triple BAR  91  allotted to the code number “7” is stopped and displayed on the pay line L, and if the random number value lies in a range of 72˜82, the double BAR  93  allotted to the code number “8” is stopped and displayed on the pay line L. And the random number value lies in a range of 83˜120, the symbol seven  94  allotted to the code number “9” is stopped and displayed on the pay line L, and if the random number value lies in a range of 121˜127, the single BAR  95  allotted to the code number “10” is stopped and displayed on the pay line L. 
   Next, in a case that the base game is conducted by utilizing three variable display portions  22  to  24  in the slot machine  1 , the winning combinations and payouts will be described with reference to  FIG. 9 .  FIG. 9  is an explanatory view showing correspondence between winning combinations and payouts when the base game is conducted while utilizing three variable display portions. In  FIG. 9 , in a case that the code number of the center reel is “0” (zero) and the code numbers of the right reel and the left reel is any of “1” to “10”, the trigger symbol (joker)  97  is won. In this case, the trigger symbol 07 is stopped and displayed on the pay line L in the variable display portion  23  and the payout thereof is the trigger for the free game, thereby game condition shifts to the free game from the base game. Here, the free game is the game which is conducted after the base game is finished and the free game is generally made beneficial for the player in many cases. For example, when game condition shifts to the free game, the player can continuously enjoy 10 games, 20 games or 30 games according to the rank of the free game, without betting coins. At that time, in the free game, winning probability of various winning combinations is generally set high, therefore the player can get many coins in many cases. This contents of the free game will be described hereinafter. 
   And if the code numbers of the right reel, the center reel and the left reel are “4” or “9”, the winning combination “7-7-7” is won. In this case, the symbol seven  94  is stopped and displayed on the pay line L in each of the variable display portions  22 ,  23  and  24 , and the payout thereof is 100 coins. And if the code numbers of the right reel, the center reel and the left reel are “1” or “7”, the winning combination “3BAR-3BAR-3BAR” is won. In this case, the 3 BAR  91  is stopped and displayed on the pay line L in each of the variable display portions  22 ,  23  and  24 , and the payout thereof is 5 coins. And if the code numbers of the right reel, the center reel and the left reel are “3” or “8”, the winning combination “2BAR-2BAR-2BAR” is won. In this case, the 2 BAR  93  is stopped and displayed on the pay line L in each of the variable display portions  22 ,  23  and  24 , and the payout thereof is 3 coins. And if the code numbers of the right reel, the center reel and the left reel are “5” or “10”, the winning combination “1 BAR-1BAR-1BAR” is won. In this case, the 1 BAR  95  is stopped and displayed on the pay line L in each of the variable display portions  22 ,  23  and  24 , and the payout thereof is 2 coins. And if the code numbers of the right reel, the center reel and the left reel are “2”, the winning combination “cherry-cherry-cherry” is won. In this case, the cherry  92  is stopped and displayed on the pay line L in each of the variable display portions  22 ,  23  and  24 , and the payout thereof is 1 coin. 
   Here, if the combination of the code numbers in the right reel, the center reel and the left reel is a combination other than the above combinations, the winning combination is lost. In this case, any one of the triple BAR  91 , the cherry  92 , the double BAR  93 , the symbol seven  94 , the single BAR  95  and the blank  96 , each of which corresponds to each code number is stopped and displayed on the pay line L in each of the variable display portions  22 ,  23  and  24 , and the payout thereof is nothing. 
   In addition to the above, in a case that the free game is conducted in the slot machine  1 , the lottery table utilized to determine the symbols stopped on the pay line L will be described with reference to  FIG. 10 . Here, in the free game, three variable display portions  22  to  24 , through which the symbol on each of three reels  220  can be seen, are utilized.  FIG. 10  is an explanatory view showing lottery tables based on which the symbols stopped and displayed on the reels, the symbols being seen and recognized through the variable display portions, are determined when the free game is conducted while utilizing three variable display portions and reels. 
   The symbol stopped and displayed on the pay line L is determined every each of three reels  220 . In order to realize this, one of the code numbers “0”˜“3” is allotted to each symbol in the symbol rows  141  to  143  shown in  FIG. 7  which are formed on each of three reels  220 , respectively, and it is provided the lottery table shown in  FIG. 10 . Further, three random number values are sampled corresponding to each of three reels  220 , through the random number sampling circuit  56 . 
   Here, in  FIG. 10 , for explanatory convenience, the reel  220 , on which the symbol row  141  is formed, the symbol row  141  being seen and recognized through the left variable display portion  22 , is indicated as the “left reel”, the reel  220 , on which the symbol row  143  is formed, the symbol row  143  being seen and recognized through the right variable display portion  24 , is indicated as the “right reel” and the reel  220 , on which the symbol row  142  is formed, the symbol row  412  being seen and recognized through the center variable display portion  23 , is indicated as the “center reel”. 
   As for the “left reel” on which the symbol row  141  is formed, if the random number value sampled by the random number sampling circuit  56  lies in a range of 0˜31, the seven symbol  191  allotted to the code number “0” is stopped and displayed on the pay line L. And if the random number value lies in a range of 32˜63, the seven symbol  191  allotted to the code number “1” is stopped and displayed on the pay line L, and if the random number value lies in a range of 64˜95, the seven symbol  191  allotted to the code number “2” is stopped and displayed on the pay line L. If the random number value lies in a range of 96˜127, the seven symbol  191  allotted to the code number “3” is stopped and displayed on the pay line L. 
   And as for the center reel on which the symbol row  142  is formed, if the random number value sampled by the random number sampling circuit  56  lies in a range of 0˜15, the seven symbol  191  allotted to the code number “0” is stopped and displayed on the pay line L. And if the random number value lies in a range of 16˜63, the blank  194  allotted to the code number “1” is stopped and displayed on the pay line L, and if the random number value lies in a range of 64˜79, the seven symbol  191  allotted to the code number “2” is stopped and displayed on the pay line L. If the random number value lies in a range of 80˜127, the blank  194  allotted to the code number “3” is stopped and displayed on the pay line L. 
   And as for the right reel on which the symbol row  143  is formed, if the random number value sampled by the random number sampling circuit  56  lies in a range of 0˜12, the triple symbol  192  allotted to the code number “0” is stopped and displayed on the pay line L. And if the random number value lies in a range of 13˜47, the double symbol  193  allotted to the code number “1” is stopped and displayed on the pay line L, and if the random number value lies in a range of 48˜85, the seven symbol  191  allotted to the code number “2” is stopped and displayed on the pay line L. If the random number value lies in a range of 86˜127, the blank  194  allotted to the code number “3” is stopped and displayed on the pay line L. 
   Next, the winning combinations and the payouts utilized when the free game is conducted while utilizing three variable display portions and reels will be described with reference to  FIG. 11 .  FIG. 11  is an explanatory view showing correspondence between winning combinations and payouts when the free game is conducted while utilizing three variable display portions and reels. In  FIG. 11 , if the code number of the right reel is any one of “0”˜“3” and the code number of the center reel is “0” or “2” and the code number of the left reel is “0”, the winning combination “7-7-Tr” is won. In this case, the seven symbol  191 , the seven symbol  191  and the triple symbol  192  are stopped and displayed on the pay line L through the variable display portions  22  to  24 , and the payout thereof is 300 coins. And if the code numbers of the right reel any one of “0”˜“3” and the code number of the center reel is “0” or “2” and the code number of the left reel is “1”, the winning combination “7-7-Do” is won. In this case, the seven symbol  191 , the seven symbol  191  and the double symbol  193  are stopped and displayed on the pay line L through the variable display portions  22  to  24 , and the payout thereof is 200 coins. And if the code number of the right reel is any one of “0”˜“3” and the code number of the center reel is “0” or “2” and the code number of the left reel is “2”, the winning combination “7-7-7” is won. In this case, the seven symbol  191 , the seven symbol  191  and the seven symbol  191  are stopped and displayed on the pay line L through the variable display portions  22  to  24 , and the payout thereof is 100 coins. 
   Here, if the combination of the code numbers in the right reel, the center reel and the left reel is a combination other than the above combinations, the winning combination is lost. In this case, any one of the seven symbol  191 , the triple symbol  192 , the double symbol  193  and the blank  194 , each of which corresponds to each code number is stopped and displayed on the pay line L in each reel through the variable display portions  22  to  24 , and the payout thereof is nothing. 
   Here, the payout expectation values in both the base game and the free game will be described with reference to  FIGS. 12 and 13 . As mentioned in the above, there exist many chances to get many coins in the free game in comparison with the base game. This fact can be explained based on the payout expectation values.  FIG. 12  is an explanatory view showing payout expectation values in the base game, and  FIG. 13  is an explanatory view showing payout expectation values in the free game. 
   In the base game conducted in the embodiment, although the lottery tables shown in  FIG. 8  is provided corresponding to the code numbers “0”-“10”, the range of the random number utilized in the lottery tables is set 0˜10 in  FIG. 12 , in order to simplify calculation of the payout expectation values, and one random number is allotted to each of the code numbers “0”˜“10” (see the table shown in  FIG. 12  A). As a result, as shown in the table of  FIG. 12B , the winning probability becomes 0.60% in all of the winning combination “7-7-7” with the payout of 100 coins, the winning combination “3BAR-3BAR-3BAR” with the payout of 5 coins, the winning combination “2BAR-2BAR-2BAR” with the payout of 3 coins and the winning combination “BAR-BAR-BAR” with the payout of 2 coins. On the other hand, the winning probability becomes 0.08% in the winning combination “cherry-cherry-cherry” with the payout of one coin. 
   Therefore, the payout expectation value after 10 base games are conducted becomes 6 in the winning combination “7-7-7” with the payout of 100 coins and becomes 0.30 in the winning combination “3BAR-3BAR-3BAR” with the payout of 5 coins. And such payout expectation value becomes 0.18 in the winning combination “2BAR-2BAR-2BAR” with the payout of 3 coins and becomes 0.12 in the winning combination “BAR-BAR-BAR” with the payout of 2 coins. Similarly, such payout expectation value becomes 0.01 in the winning combination “cherry-cherry-cherry” with the payout of one coin. The total value becomes 6.61. Further, the payout expectation value after 20 base games are conducted becomes 12 in the winning combination “7-7-7” with the payout of 100 coins and becomes 0.60 in the winning combination “3BAR-3BAR-3BAR” with the payout of 5 coins. And such payout expectation value becomes 0.36 in the winning combination “2BAR-2BAR-2BAR” with the payout of 3 coins and becomes 0.24 in the winning combination “BAR-BAR-BAR” with the payout of 2 coins. Similarly, such payout expectation value becomes 0.02 in the winning combination “cherry-cherry-cherry” with the payout of one coin. The total value becomes 13.22. And the payout expectation value after 30 base games are conducted becomes 18 in the winning combination “7-7-7” with the payout of 100 coins and becomes 1.80 in the winning combination “3BAR-3BAR-3BAR” with the payout of 5 coins. And such payout expectation value becomes 0.54 in the winning combination “2BAR-2BAR-2BAR” with the payout of 3 coins and becomes 0.36 in the winning combination “BAR-BAR-BAR” with the payout of 2 coins. Similarly, such payout expectation value becomes 0.02 in the winning combination “cherry-cherry-cherry” with the payout of one coin. The total value becomes 20.72. 
   And in the free game conducted in the embodiment, although the lottery tables shown in  FIG. 10  is provided corresponding to the code numbers “0”˜“3”, the range of the random number utilized in the lottery tables is set 0˜3 in  FIG. 13 , in order to simplify calculation of the payout expectation values, and one random number is allotted to each of the code numbers “0”˜“3” (see the table shown in  FIG. 13A ). As a result, as shown in the table of  FIG. 13B , the winning probability becomes 9.38% in all of the winning combination “7-7-Tr” with the payout of 300 coins, the winning combination “7-7-Do” with the payout of 200 coins, the winning combination “7-7-7” with the payout of 100 coins. 
   Therefore, the payout expectation value after 10 free games are conducted becomes 281.3 in the winning combination “7-7-Tr” with the payout of 300 coins and becomes 187.5 in the winning combination “7-7-Do” with the payout of 200 coins. And such payout expectation value becomes 93.8 in the winning combination “7-7-7” with the payout of 100 coins. The total value becomes 562.5. Further, the payout expectation value after 20 free games are conducted becomes 562.5 in the winning combination “7-7-Tr” with the payout of 300 coins and becomes 375.0 in the winning combination “7-7-Do” with the payout of 200 coins. And such payout expectation value becomes 187.5 in the winning combination “7-7-7” with the payout of 100 coins. The total value becomes 1125. And the payout expectation value after 30 free games are conducted becomes 843.8 in the winning combination “7-7-Tr” with the payout of 300 coins and becomes 562.5 in the winning combination “7-7-Do” with the payout of 200 coins. And such payout expectation value becomes 281.3 in the winning combination “7-7-7” with the payout of 100 coins. The total value becomes 1687.5. 
   As mentioned above, the payout expectation value in the free game is made substantially 85 times as large in comparison with that in the base game, in all cases of 10 games, 20 games and 30 games. Thus, there exist many cases to be able to obtain many coins in the free game than in the base game, as a result, the free game is more beneficial for the player than the base game. 
   In addition to the above, the main process program executed in the slot machine  1  will be described with reference to  FIG. 14 .  FIG. 14  is a flowchart of the main process program. In  FIG. 14 , at first, in step (abbreviated as “S” hereinafter)  11 , start acceptance process in  FIG. 15  mentioned later is done. This start acceptance process is the process to accept the switch signal output from the start switch  57 , the spin switch  58 , the 1-BET switch  59 , the 3-BET switch  60  or the 5-BET switch  61 , based on operation of the start lever  17 , the SPIN/REPEAT BET button  12 , the 1-BET button  11 , the 3-BET button or the 5-BET button  14 . At the time that the switch signal output from each switch is accepted, the game is started. 
   And in S 12 , the lottery process in  FIG. 16  mentioned later is done based on the switch signal output from the start switch  57 , the spin switch  58 , the 1-BET switch  59 , the 3-BET switch  60  or the 5-BET switch  61 . 
   Here, if the trigger symbol (joker) is won and the free game is triggered, the number of times that the free games are continuously executed is determined, and such number of times is selected, for example, among 10 games, 20 games and 30 games by the lottery. 
   In S 13 , the base game process shown in  FIG. 17  is done. Thereafter, procedure shifts to S 14  and it is determined whether the trigger of the free game is realized or not. Concretely speaking, in the lottery process in S 12 , if the random number value of the center reel sampled by the random number sampling circuit  56  is 0 (zero), the free game is triggered (S 14 : YES), therefore procedure shifts to S 15  and the free game process in  FIG. 18  is done, thereafter the main process program is finished. On the other hand, if the random number value of the center reel sampled by the random number sampling circuit  56  in the lottery process in S 12  lies in a range of 1˜127, the free game is not triggered (S 14 : NO), therefore the main process program is finished. 
   Next, the start acceptance process program done in the slot machine  1  will be with reference to  FIG. 15 .  FIG. 15  is a flowchart showing a start acceptance process program. In S 11  of the main process program shown in  FIG. 14 , the start acceptance process is done. Concretely, at first, in S 21  in  FIG. 15 , it is determined whether a predetermined time (for example, 15 seconds) is elapsed or not. Here, if it is determined that the predetermined time is not elapsed (S 21 : NO), procedure directly shifts to S 23 . On the other hand, if it is determined that the predetermined time is elapsed (S 21 : YES), the demonstration effect is conducted on the upper liquid crystal display  3  or the lower liquid crystal display  4  in S 22 , thereafter procedure shifts to S 23 . And in S 23 , it is determined whether or not the start lever  17 , the SPIN/REPEAT BET button  12 , the 1-BET button  11 , the 3-BET button  13  or the 5-BET button  14  is operated. Here, if it is determined that the start lever  17  or the above buttons are not operated (S 23 : NO), procedure returns to S 21  and the above processes are repeated. On the other hand, if it is determined that the start lever  17  or the above buttons are operated (S 23 : YES), procedure returns to the main process program in  FIG. 14  even while the demonstration effect is conducted, and procedure shifts to the lottery process in S 12 . 
   Here, in determination done in S 23 , such determination May be done based on the other input signals in addition to the signals output from the start lever  17  and the above buttons. 
   Next, the lottery process program conducted in the slot machine  1  will be described with reference to  FIG. 16 .  FIG. 16  is a flowchart showing a lottery process program. In S 12  of the main process program in  FIG. 14 , the lottery process is done. Concretely, at first, in S 31  in  FIG. 16 , the symbol determination process is done. Here, the symbols stopped and displayed on the pay line L are determined every each of the variable display portions  22  to  24 . Concretely, as mentioned above, three random number values are sampled by the random number sampling circuit  56  corresponding to each of the variable display portions  22  to  24 , and the symbols stopped and displayed are determined on the basis of the lottery tables in  FIG. 8 , by utilizing the code numbers. And if the symbols stopped and displayed on the pay lien L are determined, the winning combination determining process is done in S 32 , thereafter procedure returns to the main process program in  FIG. 14  and shifts to the base game process. Here, in the winning combination determining process, concretely speaking, the winning combination and the payout are determined on the basis of the table in  FIG. 9  by utilizing the code numbers obtained in S 31 . 
   Next, the base game process program conducted in the slot machine  1  will be described with reference to  FIG. 17 .  FIG. 17  is a flowchart showing a base game process program. In S 13  of the main process program in  FIG. 14 , the base game process is done. Concretely, In S 41  in  FIG. 17 , at first, the symbols are scrolled in the variable display portions  22  to  24 , based on the switch signal output from the start switch  57 , the spin switch  58 , the 1-BET switch  59 , the 3-BET switch  60  or the 5-BET switch  61 . At that time, since scroll of the symbols displayed on the variable display portions  22  to  24  is done, three reels  220  in the cabinet  2  cannot be seen and recognized through the variable display portions  22  to  24 . 
   And in S 42 , when the stop buttons  27  to  29  corresponding to the variable display portions  22  to  24  on which the symbols are scrolled are pressed by the player, scroll of the symbols on the variable display portions  22  to  24  is stopped by utilizing the switch signal output from the stop buttons  27  to  29  which are pressed as the trigger signal. 
   Here, in the embodiment, each of the stop buttons  27  to  29  has no relation with so-called “observation push” which is done for purpose to allow technical intervention by the player. And the switch signal output from each of the stop buttons  27  to  29  is used to the end only as the trigger when the symbols scrolled on the variable display portions  22  to  24  are stopped and displayed. Therefore, the symbols on each of the variable display portions  22  to  24  are stopped and displayed thereon based on only the lottery result obtained in S 31  in  FIG. 16 . In other words, stop operation of the stop buttons  27  to  29  can be utilized as the trigger to execute the effect done until the symbols to be stopped, which are determined by the lottery, are stopped. 
   And in S 43 , coins are paid out corresponding to the payout set beforehand based on the table in  FIG. 9 , according to the symbol combination of the winning combination which is stopped and displayed on the variable display portions  22  to  24  in S 42 . Here, after the process in S 43 , procedure returns to the main process program and shifts to S 14 . 
   Next, the free game process program conducted in the slot machine  1  will be described with reference to  FIG. 18 .  FIG. 18  is a flowchart showing a free game process program. In S 14  of the main process program in  FIG. 14 , if it is determined that the trigger of the free game is realized (S 14 : YES), the free game process is done in S 15  in  FIG. 14 . Concretely, at first, procedure shifts to S 51  in  FIG. 18  and the lottery process in the free game is conducted. Here, in the free game, the symbol stopped and displayed on the pay line L through the variable display portions  22  to  24  is determined every each of the reels  220 . Concretely, as mentioned above, three random number values corresponding to the reels  220  are sampled by the random number sampling circuit  56  at the timing that procedure shifts to S 51  and the symbols to be stopped and displayed are determined on the basis of the lottery tables in  FIG. 10 , by utilizing the code numbers. Further, the winning combination is also determined in S 51 . Concretely speaking, as mentioned, the winning combination and the payout are determined on the basis of the table in  FIG. 11 , by utilizing the code numbers. 
   In S 52 , each of the variable display portions  22  to  24  on the lower liquid crystal display  4  is controlled so as to become transparent, thereby the variable display portions  22  to  24  are made in a state that three reels  220  can be seen and recognized therethrough and rotation of three reels  220  is automatically started. Thereafter, in S 53 , it is displayed on the lower liquid crystal display  4  the guidance to call player&#39;s attention so as to press the stop buttons  27  to  29  corresponding to each of the reels  220 . As such guidance, for example, it is conceivable that the message (for example, “switch on”) to call player&#39;s attention so as to press the stop buttons  27  to  29  corresponding to each of the reels  220  is displayed or blink of the stop buttons  27  to  29  is done. 
   Thereafter, if the player presses any one of the stop buttons  27  to  29 , rotation of three reels  220  is automatically stopped by utilizing the switch signal output from the pressed stop button as the trigger signal. Here, in the embodiment, each of the stop buttons  27  to  29  has no relation with so-called “observation push” which is done for purpose to allow technical intervention by the player. And the switch signal output from each of the stop buttons  27  to  29  is used to the end only as the trigger when the symbols scrolled on the reels  220  (the variable display portions  22  to  24 ) are stopped and displayed. Therefore, the symbols on each of the reels  220  (the variable display portions  22  to  24 ) are stopped and displayed thereon based on only the lottery result determined in S 51 . In other words, stop operation of the stop buttons  27  to  29  can be utilized as the trigger to execute the effect done until the symbols to be stopped, which are determined by the lottery, are stopped. However, in the free game, since the payout expectation value is high (see  FIG. 13 ) and the player can obtain more beneficial state therein than in the base game, probability that the player can obtain the payout every pressing any one of the stop buttons  27  to  29  is high, thereby the player can continuously enjoy the free games. 
   And after the process in S 53  is executed, coins corresponding to the winning combination are paid out in S 54 . Next, procedure shifts to S 55  and it is determined whether the number of times of the free games which are executed reaches to the number of times of the free games determined in S 12  in  FIG. 14  or not. At that time, if it is determined that the number of times of the free games which are executed does not reach to the number of times of the free games determined in S 12  in  FIG. 14  (S 55 : NO), procedure returns to S 51  and the above processes are repeated. On the other hand, if it is determined that the number of times of the free games reaches to the number of times determined S 12  (S 55 : YES), the free game process is finished. 
   Next, the timing of the shift effect process conducted in the slot machine  1  of the embodiment will be described with reference to  FIG. 26 .  FIG. 26  is a flowchart showing a rotation process program. In the flowchart of  FIG. 26 , the rotation process in S 41  of  FIG. 17  done in the base game is described in detail in order to clarify the timing that shift effect process is done. That is to say, after the lottery process in S 12  of the main process program shown in  FIG. 14  is executed, procedure shifts to S 61  in the rotation process program shown in  FIG. 26  and variable display of three symbol rows  41  to  43  are automatically started on the variable display portions  22  to  24  in the lower liquid crystal display  4 . Thereafter, in S 62 , it is determined whether the shift effect is executed or not. At that time, if it is determined that the shift effect is executed (S 62 : YES), procedure shifts to S 63 . And after the shift effect is executed, procedure returns to the base game shown in  FIG. 17  and the stop control process is done in S 42 . On the other hand, if it is determined that the shift effect is not executed (S 62 : NO), procedure directly returns to the base game shown in  FIG. 17  and the stop control process is done in S 42 . 
   Here, in S 62  of  FIG. 26 , determination whether the shift effect is executed or not is done based on the lottery result in S 131  of the notice lottery process in the lottery process shown in  FIG. 25 .  FIG. 25  is a flowchart of the lottery process. Here, as for the flowchart of the lottery process, although such flowchart has been already described with reference to  FIG. 16 , the flowchart of  FIG. 25  is represented by adding the notice lottery process to the flowchart in  FIG. 16 , in order to clarify the timing at which the notice lottery process is conducted. That is to say, as shown in  FIG. 25 , in the lottery process, after the symbol determination process in S 31  and the winning combination determination process in S 32 , procedure shifts to S 131  and the notice lottery process is conducted. In the notice lottery process in S 131 , it is determined whether the shift effect process is done or not based on the random number value sampled by the random number sampling circuit  56 . And if it is determined that shift effect process is done, on-sate of a flag is stored in the RAM  52 , and on the other hand, if it is determined that the shift effect process is not done, off-state of the flag stored in the RAM  52  is maintained as it is. Therefore, determination whether the shift effect is done or not in S 62  of  FIG. 26  is done based on whether the flag stored in the RAM  52  is on-state or off-state. Here, when the start acceptance process in S 11  in the main process program shown in  FIG. 14  is done, the flag stored in the RAM  52  is always initialized. 
   Next, contents of the shift effect process will described. As mentioned, in order that the shift effect process is done, the rotation process in the base game has to be executed. Concretely, in the base game done on the lower liquid crystal display  4 , the symbols are scrolled and variably displayed on the variable display portions  22  to  24 . And as shown in  FIG. 22A , the demonstration effect that the big tree near the house is struck by lightning is displayed on the lower liquid crystal display  4 . At that time, effective sounds are output according to blink of lightning and the lower liquid crystal display  4  is controlled so as to become transparent or opaque. Thereby, in the lower liquid crystal display  4 , it is reciprocally repeated the state that the reels  220  in the cabinet  2  can be seen and recognized and the state that the reels  220  cannot be seen and recognized. This repetition May be periodically done with a predetermined interval (for example, every 2 seconds) and May be randomly done by utilizing the random number values. The contents of the demonstration effect are stored in the image ROM  82 . Thereafter, as shown in  FIG. 22B , each of the variable display portions  22  to  24  is made transparent and each of the reels  220  in the cabinet  2  becomes to be able to be seen and recognized through the variable display portions  22  to  24 . And as shown in  FIG. 22C , the demonstration effect that the lightning goes away from the big tree near the house is displayed on the lower liquid crystal display  4 . At that time, effective sounds are output according to blink of lightning and the lower liquid crystal display  4  is controlled so as to become transparent or opaque. Thereby, in the lower liquid crystal display  4 , it is reciprocally repeated the state that the reels  220  in the cabinet  2  can be seen and recognized and the state that the reels  220  cannot be seen and recognized. This repetition May be periodically done with a predetermined interval (for example, every 2 seconds) and May be randomly done by utilizing the random number values. The contents of the demonstration effect are stored in the image ROM  82 . Thereafter, as shown in  FIG. 22D , each of the variable display portions  22  to  24  is made transparent and each of the reels  220  in the cabinet  2  becomes to be able to be seen and recognized through the variable display portions  22  to  24 . 
   Further, procedure returns to the base game shown in  FIG. 17  and when the stop control process is done in S 42 , the symbols variable displayed on each of the variable display portions  22  to  24  are automatically stopped. For example, as shown in  FIG. 20 , the symbols are stopped on the pay line L in the variable display portions  22  to  24 . 
   Here, although the above mentioned shift effect process is done in a case that procedure progresses to the shift effect process in S 63  after the rotation start process in the base game is conducted (S 61 ), the shift effect process may be done before the rotation start process is executed in the base game (S 61 ). In this case, for example, as shown in  FIG. 20 , the shift effect process shown in  FIGS. 22A to 22D  is conducted in the state that the symbols on the variable display portions  22  to  24  are stopped and displayed on the pay line L. Thereafter, as shown in  FIG. 21 , the symbols are scrolled and variably displayed on each of the variable display portions  22  to  24 . 
   And as for the demonstration effect of the shift effect process, a plurality of patterns for the demonstration effect may be stored in the image ROM  82 . At that time, for example, as shown in  FIG. 19 , three patterns for the demonstration effect may be stored in the image ROM  82  and the demonstration effect may be determined by conducting the lottery using the random number values. That is to say, in  FIG. 19 , the range of the random number values utilized in the lottery table is set in a range of 0˜63. And if the random number value sampled by the random number sampling circuit  56  lies in a range of 0˜2, the shift effect process according to the demonstration effect is executed on the basis of the effect pattern  1 . And if the random number value sampled by the random number sampling circuit  56  lies in a range of 3˜15, the shift effect process according to the demonstration effect is executed on the basis of the effect pattern  2 . And if the random number value sampled by the random number sampling circuit  56  lies in a range of 16˜63, the shift effect process according to the demonstration effect is executed on the basis of the effect pattern  3 . Here, as for the timing at which the random number value is sampled by the random number sampling circuit  56 , it is desirable that the random number value is sampled right before procedure shifts to the start acceptance process in  FIG. 15  or in the notice lottery process in S 131  shown in  FIG. 25 . 
   As mentioned in detail, in the slot machine  1  of the embodiment, the base game is executed by controlling the lower liquid crystal display  4  on the cabinet  2  through the CPU  50  (S 13  in  FIG. 14 ) and the free game is executed by controlling the reels  220  in the cabinet  2  (S 15  in  FIG. 14 ). Thus, the slot machine  1  is the gaming machine that the base game is executed by utilizing the lower liquid crystal display  4  on the cabinet  2  and the free game is executed by utilizing the reels  220  in the cabinet  2 . Further, the lower liquid crystal display  4  on the cabinet  2  arranged in front of the reels  220  in the cabinet  2  when seen from the front side of the slot machine  1  is controlled by the CPU  50  so that the shift effect process is conducted (S 63  in  FIG. 26 ) through the openings  35 A˜ 35 C of the diffusion sheet  35  and the openings  36 A  36 C of the light guiding plate  36  if it is determined to execute the shift effect (S 62 : YES) which is the effect display utilizing change of light transmittance of the lower liquid crystal display  4  on the cabinet  2 . Thereby, the effect conducted by controlling light transmittance of the lower liquid crystal display  4  on the cabinet  2  (see  FIGS. 22A and 22C ) is executed during the base game in which the lower liquid crystal display  4  on the cabinet  2  is utilized. Concretely, in order to be able to recognize the reels  220  in the cabinet  2 , the demonstration effect that the big tree near the house is struck by lightning is displayed and at that time, in the lower liquid crystal display  4 , it is reciprocally repeated the state that the reels  220  in the cabinet  2  can be seen and recognized and the state that the reels  220  in the cabinet  2  cannot be seen and recognized, according to blink of lightning. On the other hand except for a case that it is determined to execute the shift effect (S 62 : YES) which is the effect display utilizing change of light transmittance of the lower liquid crystal display  4  on the cabinet  2  or a case that the free game is executed by utilizing the reels  220  in the cabinet  2 , the lower liquid crystal display  4  conceals the reels  220  in the cabinet  2 . Therefore, while the base game is conducted by utilizing the lower liquid crystal display  4  on the cabinet  2 , the above mentioned effect is conducted by controlling light transmittance of the lower liquid crystal display  4  on the cabinet  2 . Thereby, device is done in the display mode that the reels  220  in the cabinet  2  can be seen. As a result, interest for the free games done by the reels  220  can be highly maintained and variegated effects can be done. 
   In particular, while the base game is conducted by utilizing the lower liquid crystal display  4  on the cabinet  2 , if the effect is done by controlling light transmittance of the lower liquid crystal display  4  on the cabinet  2  (for example, if light transmittance coefficient of the lower liquid crystal display  4  is remarkably changed between high and low values), the player can see and recognize the reels  220  in the cabinet  2 , the reels  220  having no relation with the base game. Thus, it can be raised expectation concerning with what is conducted thereafter. 
   Further, if it is determined by the CPU  50  to conduct the effect which is the effect display utilizing change of light transmittance of the lower liquid crystal display  4  on the cabinet  2  (S 62 : YES), it is executed the effect by controlling light transmittance of the lower liquid crystal display  4  on the cabinet  2 . Here, even while the base game is done by utilizing the lower liquid crystal display  4  on the cabinet  2 , such effect is not necessarily conducted. Therefore, if such effect is done by controlling light transmittance of the lower liquid crystal display  4 , it can be highly raised expectation concerning with what is conducted thereafter. 
   And while the base game is done by utilizing the lower liquid crystal display  4  on the cabinet  2 , the shift effect (see  FIG. 21 ), which is executed by controlling light transmittance of the lower liquid crystal display  4 , is conducted when the symbols are scrolled and variable displayed on each of the variable display portions  22  to  24  (see  FIG. 26 ). Thereby, since the shift effect is done while the base game is progressed by utilizing the lower liquid crystal display  4 , it can be raised expectation concerning with what is conducted thereafter, by displaying a close relation with the game result of the base game (which means that the symbols are stopped and displayed on the pay line L on each of the variable display portions  22  to  24 ) utilizing the lower liquid crystal display  4 . 
   Here, the present invention is not limited to the above embodiment and various modifications can be done within the scope of the present invention. 
   For example, in the slot machine  1  of the embodiment, in the above mentioned effect process, the demonstration effect that the big tree near the house is struck by lightning or lightning goes away is displayed on the lower liquid crystal display  4  (S 63  in  FIG. 26 ) and it is reciprocally repeated the state that the reels  220  in the cabinet  2  can be seen and recognized and the state that the reels  220  in the cabinet  2  cannot be seen and recognized, according to blink of lightning, thereby visible state and invisible state of the reels  220  in the cabinet  2  are repeated. However, it is conceivable that the lower liquid crystal display  4  is gradually made transparent and is gradually changed in the visible state that the reels  220  in the cabinet  2  can be seen and recognized therethrough. And the lower liquid crystal display  4  is gradually made opaque and is gradually changed in the invisible state that the reels  220  in the cabinet  2  can not be seen and recognized. 
   And as for the timing of the shift effect process done in the slot machine  1  of the embodiment, another sample can be explained with reference to  FIG. 26 .  FIG. 26  is a flowchart showing a rotation process program in order to clarify the timing that the shift effect process is done. In the flowchart of  FIG. 26 , the rotation process in S 52  of  FIG. 18  done in the free game is described in detail. That is to say, in the free game process of  FIG. 18 , after the free game process in S 51  is executed, procedure shifts to S 61  in the rotation process program shown in  FIG. 26  and the variable display portions  22  to  24  are made transparent, thereby it is realized the state that three reels  220  can be seen and recognized and three reels  220  are automatically started to rotate. Thereafter, in S 62 , it is determined whether the shift effect is executed or not. At that ire, if it is determined that the shift effect is executed (S 62 : YES), procedure shifts to S 63 . And after the shift effect is executed, procedure returns to the free game shown in  FIG. 18  and the stop control process is done in S 53 . On the other hand, if it is determined that the shift effect is not executed (S 62 : NO), procedure directly returns to the free game shown in  FIG. 18  and the stop control process is done in S 53 . 
   Here, in S 62  of  FIG. 26 , determination whether the shift effect is executed or not is done based on the lottery result in S 131  of the notice lottery process in the lottery process shown in  FIG. 25 .  FIG. 25  is a flowchart of the lottery process. Here, as for the flowchart of the lottery process, although such flowchart has been already described with reference to  FIG. 16 , the flowchart of  FIG. 25  is represented by adding the notice lottery process to the flowchart in  FIG. 16 , in order to clarify the timing at which the notice lottery process is conducted. That is to say, as shown in  FIG. 25 , in the lottery process, after the symbol determination process in S 31  and the winning combination determination process in S 32 , procedure shifts to S 131  and the notice lottery process is conducted. In the notice lottery process in S 131 , it is determined whether the shift effect process is done or not based on the random number value sampled by the random number sampling circuit  56 . And if it is determined that shift effect process is done, on-sate of a flag is stored in the RAM  52 , and on the other hand, if it is determined that the shift effect process is not done, off-state of the flag stored in the RAM  52  is maintained as it is. Therefore, determination whether the shift effect is done or not in S 62  of  FIG. 26  is done based on whether the flag stored in the RAM  52  is on-state or off-state. Here, when the start acceptance process in S 11  in the main process program shown in  FIG. 14  is done, the flag stored in the RAM  52  is always initialized. 
   Next, contents of the shift effect process will described. As mentioned, in order that the shift effect process is done, the rotation process in the free game has to be executed. In order that, in the base game done on the lower liquid crystal display  4 , the symbols are scrolled and variably displayed on the variable display portions  22  to  24 . Thereafter, as shown in  FIG. 20 , the trigger symbol  97  is stopped and displayed on the pay line L in the variable display portion  23 , thereby game condition shifts to the free game from the base game. Here, at that time, any one of the symbols may be stopped and displayed on the pay line of the variable display portions  22  and  24 . And game condition shifts to the free game, as shown in  FIG. 23A , the variable display portions  22  to  24  are made transparent, thereby it becomes the state that each of the reels  220  in the cabinet  2  can be seen and recognized. Thereafter, rotation start process in the free game is executed (S 61 ) and as shown in  FIG. 23B , the symbols rows  141  to  143  formed on the reels  220  are scrolled and variably displayed. Thereafter, when procedure progresses to the shift effect process in S 63 , as shown in  FIG. 23C , the demonstration effect that the big tree near the house is struck by lightning is displayed on the lower liquid crystal display  4 . At that time, effective sounds are output according to blink of lightning and the lower liquid crystal display  4  is controlled so as to become transparent or opaque. Thereby, in the lower liquid crystal display  4 , it is reciprocally repeated the state that the reels  220  in the cabinet  2  can be seen and recognized and the state that the reels  220  cannot be seen and recognized. This repetition May be periodically done with a predetermined interval (for example, every 2 seconds) and May be randomly done by utilizing the random number values. The contents of the demonstration effect are stored in the image ROM  82 . Thereafter, as shown in  FIG. 23D , the demonstration effect that the lightning goes away from the big tree near the house is displayed on the lower liquid crystal display  4 . At that time, effective sounds are output according to blink of lightning and the lower liquid crystal display  4  is controlled so as to become transparent or opaque. Thereby, in the lower liquid crystal display  4 , it is reciprocally repeated the state that the reels  220  in the cabinet  2  can be seen and recognized and the state that the reels  220  cannot be seen and recognized. This repetition May be periodically done with a predetermined interval (for example, every 2 seconds) and may be randomly done by utilizing the random number values. The contents of the demonstration effect are stored in the image ROM  82 . 
   Thereafter, procedure returns to the free game shown in  FIG. 18 , when the stop control process in S 53  is done, rotation of three reels  220  is automatically stopped. For, example, as shown in  FIG. 23A , a part of the symbol rows  141  to  143  variably displayed by the reels  220  in the cabinet  2  is stopped and displayed don the pay line L. 
   Here, although the above mentioned shift effect is executed when procedure shifts to the shift in S 63  after rotation start process in the free game is executed (S 61 ), the shift effect process may be conducted before rotation start process in the free game is executed (S 61 ). In this case, as shown in  FIG. 24A , each of the variable display portions  22  to  24  are made transparent and it is realized the state that the reels  220  in the cabinet  2  can be seen and recognized, thereafter as shown in  FIG. 24B , the demonstration effect that the big tree near the house is struck by lightning is displayed on the lower liquid crystal display  4 . At that time, effective sounds are output according to blink of lightning and the lower liquid crystal display  4  is controlled so as to become transparent or opaque. Thereby, in the lower liquid crystal display  4 , it is reciprocally repeated the state that the reels  220  in the cabinet  2  can be seen and recognized and the state that the reels  220  cannot be seen and recognized. This repetition May be periodically done with a predetermined interval (for example, every 2 seconds) and May be randomly done by utilizing the random number values. The contents of the demonstration effect are stored in the image ROM  82 . Further, as shown in  FIG. 24C , the demonstration effect that the lightning goes away from the big tree near the house is displayed on the lower liquid crystal display  4 . At that time, effective sounds are output according to blink of lightning and the lower liquid crystal display  4  is controlled so as to become transparent or opaque. Thereby, in the lower liquid crystal display  4 , it is reciprocally repeated the state that the reels  220  in the cabinet  2  can be seen and recognized and the state that the reels  220  cannot be seen and recognized. This repetition May be periodically done with a predetermined interval (for example, every 2 seconds) and may be randomly done by utilizing the random number values. The contents of the demonstration effect are stored in the image ROM  82 . Thereafter, as shown in  FIG. 24D , the symbols rows  141  to  143  formed on the reels  220  are scrolled and variably displayed. 
   And in the slot machine  1  of the embodiment, although the symbols to be stopped on the pay line L are determined every each of the variable display portions  22  to  24  based on the random number value sampled by the random number sampling circuit  56  in the base game (see  FIG. 8 ), all symbols to be stopped on the pay line L in the variable display portions  22  to  24  may be determined according to the random number value sampled by the random number sampling circuit  56 . In order that, the lottery table of the winning combinations shown in  FIG. 27  is utilized.  FIG. 27  is an explanatory view showing a lottery table of the winning combinations and payouts when the base game is done by utilizing three variable display portions. 
   In  FIG. 27 , the random number value range utilized in the lottery table lies in 0˜1270. If the random number value sampled by the random number sampling circuit  56  lies in a range of 0˜9, the joker is won, thereby the trigger of the free game is obtained. In this case, the trigger symbol  97  is stopped and displayed on the pay line L in the variable display portion  23 , thereby game condition can be shifted to the free game. 
   And if the random number value sampled by the random number sampling circuit  56  lies in a range of 10˜32, the winning combination “7-7-7” is won and the payout thereof is 100 coins. In this case, the symbol seven  94  is stopped and displayed on the pay line L in each of the variable display portions  22  to  24 . Similarly, if the random number value sampled lies in a range of 33˜35, the winning combination “3BAR-3BAR-3BAR” is won and the payout thereof is 5 coins. In this case, the triple BAR  91  is stopped and displayed on the pay line L in each of the variable display portions  22  to  24 . And similarly, if the random number value sampled lies in a range of 36˜58, the winning combination “2BAR-2BAR-2BAR” is won and the payout thereof is 3 coins. In this case, the double BAR  93  is stopped and displayed on the pay line L in each of the variable display portions  22  to  24 . Similarly, if the random number value samples lies in a range of 59˜203, the winning combination “BAR-BAR-BAR” is won and the payout thereof is 2 coins. In this case, the single BAR  95  is stopped and displayed on the pay line L in each of the variable display portions  22  to  24 . Similarly, if the random number value samples lies in a range of 204˜257, the winning combination “cherry-cherry-cherry” is won and the payout thereof is 1 coin In this case, the cherry  92  is stopped and displayed on the pay line L in each of the variable display portions  22  to  24 . 
   Here, if the random number value sampled lies in a range of 258˜1270, the winning combinations is lost. In this case, the symbol combination other than the above mentioned combinations is stopped and displayed on the pay line L and the payout thereof is nothing. 
   And in the slot machine  1  of the embodiment, although the symbols stopped and displayed on the pay line L through the variable display portions  22  to  24  are determined every each of the reels  220  in the free game based on the random number values sampled by the random number sampling circuit  56  (see  FIG. 10 ), all symbols stopped and displayed on the pay line L through the variable display portions  22  to  24  may be determined based on the random number values sampled by the random number sampling circuit  56 . To realize this, the lottery table shown in  FIG. 28  is utilized.  FIG. 28  is an explanatory view of a lottery table showing correspondence between winning combinations and payouts when the free game is conducted while utilizing three variable display portions and reels. 
   In  FIG. 28 , the random number value range lies in 0˜127. And if the random number value sampled by the random number sampling circuit  56  lies in a range of 0˜11, the winning combination “7-7-Tr” is won and the payout thereof is 300 coins. In this case, the seven symbol  191 , the seven symbol  191  and the triple symbol  192  are stopped and displayed on the pay line L. Similarly, if the random number value sampled lies in a range of 12˜49, the winning combination “7-7-Do” is won and the payout thereof is 200 coins. In this case, the seven symbol  192 , the seven symbol  191  and the double symbol  193  are stopped and displayed on the pay line L. And similarly, if the random number value sampled lies in a range of 50˜87, the winning combination “7-7-7” is won and the payout thereof is 100 coins. In this case, the seven symbol  191 , the seven symbol  191  and the seven symbol  191  are stopped and displayed on the pay line L. 
   Here, if the random number value sampled lies in a range of 88˜127, the winning combination is lost. In this case, the symbol combination other than the above mentioned combinations is stopped and displayed on the pay line L. The payout is nothing. 
   And in the slot machine  1  of the embodiment, although the free game is conducted as the second game, the present invention is not limited to this. For example, the so-called second game may be done continuously to the base game. 
   And in the slot machine  1  of the embodiment, although the game utilizing the symbols is done in the base game and the free game (see  FIGS. 6 and 7 ), the present invention is not limited to this. For example, the game utilizing cards such as poker may be conducted. 
   Further, in the lower liquid crystal display  4  of the slot machine  1  of the embodiment, as shown in  FIG. 3 , the variable display portion  22  (see  FIG. 1 ) is constructed by superimposing the openings  35 A˜ 38 A so as to coincide with each other, and the variable display portion  23  (see  FIG. 1 ) is constructed by superimposing the openings  35 B˜ 38 B so as to coincide with each other and the variable display portion  24  (see  FIG. 1 ) is constructed by superimposing the openings  35 C˜ 38 C so as to coincide with each other, thereby the light transmitting areas to retain visibility of the variable display portions  22  to  24  are formed. And shapes of three light transmitting areas corresponding to the variable display portions  22  to  24  have rectangular shapes so as to coincide with the width of each reel  220 . The present invention is not limited to this. For example, the entire plane of the lower liquid crystal display  4  may be transparent. 
   And in the lower liquid crystal display  4  of the slot machine  1  of the embodiment, the symbol rows  41 ˜ 43  shown in  FIG. 6  are scrolled, stopped and displayed on the variable display portions  22  to  24  which are made opaque in the base game, and the symbol rows shown in  FIG. 7  are scrolled, stopped and displayed through the variable display portions  22  to  24  which are made transparent in the free game. At this point of view, the symbol rows  41 ˜ 43  shown in  FIG. 6  may be scrolled, stopped and displayed on the areas other than the variable display portions  22  to  24  in the base game. 
   Further, in the slot machine  1  of the embodiment, by controlling light transmittance of the lower liquid crystal display  4 , it is reciprocally repeated the state that the reels  220  in the cabinet  2  can be seen and recognized and the state that the reels  220  in the cabinet  2  cannot be seen and recognized. At this point of view, the shutter mechanism may be arranged between the lower liquid crystal display  4  and the reels  220  and it may be reciprocally repeated the state that the reels  220  in the cabinet  2  can be seen and recognized and the state that the reels  220  in the cabinet  2  cannot be seen and recognized, by utilizing such shutter mechanism. 
   And in the slot machine  1  of the embodiment, the lower liquid crystal display  4  is utilized for changing two states, in one of which the reels  220  can be seen and recognized and in another of which the reels  220  cannot be seen and recognized. The present invention is not limited to this. For example, the transparent EL and the like may be utilized instead of the lower liquid crystal display  4 .