JP2001170249A - Slot machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To drastically suppress a labor and a cost for the small-scale redecoration of a slot machine. SOLUTION: A liquid crystal control substrate 46 is fixed to the rear surface of a front door 22 covered with a transparent resin case 48. In this substrate 46, a picture control circuit 300 for controlling the display of a liquid-crystal display device 44 is constituted. Thus, on replacing the door 22 for varying the appearance of it in order to perform the small-scale redecoration of the slot machine 21, the circuit 300 being the display control circuit of the device 44 can also be replaced with a new circuit together with the door 22. Further, while replacing the circuit 300 with a new circuit, a main control circuit 100 and a sub-control circuit 200 can use a conventional circuit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slot machine provided with a display device for displaying various information in addition to a variable display device for variably displaying a plurality of symbols.

[0002]

2. Description of the Related Art Conventionally, as this kind of slot machine, for example, there is a slot machine 1 shown in FIG. Behind the front door 2, three reels 3, 4, and 5 are arranged in three rows. Various symbols are drawn on the outer periphery of each of the reels 3, 4, and 5, and are observed through windows 6, 7, and 8 formed in the front door 2. The windows 6 to 8 have winning lines L1 and L2
A, L2B, L3A, and L3B are described, and the slot machine game is performed by operating each of the stop buttons 9, 10, and 11 depending on whether or not a predetermined combination of symbols is stopped on any one of the winning lines. Done.

The winning mode is determined by random number lottery performed by the winning mode determining means immediately after the start lever 12 is operated, and is already determined before each of the reels 3 to 5 is stopped by the player. The winning mode determined inside the machine is stored as an internal winning flag. afterwards,
The rotation of each of the reels 3 to 5 is stopped and controlled by the reel stop control circuit in accordance with the player's stop button operation and the type of the internal winning flag, and the winning symbol combination represented by the internal winning flag is stopped and displayed on the winning line. Then, the player can actually experience the winning.

[0004] A liquid crystal display device 13 is provided on the right front door 2 of each of the reels 3 to 5. The liquid crystal display device 13 is a display device that displays various kinds of information, and displays the rotation of each of the reels 3 to 5, displays a game history, and performs effects during a bonus game.

FIG. 2 is a view showing the internal structure when the front door 2 of the slot machine 1 is opened. Each device including the reels 3, 4 and 5 is housed in a housing 14. A main control board 15 is provided inside the rear surface of the housing 14 above the reels 3 to 5.
Is attached. The winning mode determination means and the reel stop control circuit are configured as a main control circuit of the main control board 15. A display control circuit for controlling the display of the liquid crystal display device 13 is also configured on the main control board 15.

[0006]

Generally, the above-mentioned slot machine 1 installed in a game store is renewed after a certain period of time in order to change the game player's point of view. Since the refurbishment is performed frequently, instead of replacing the entire game console every time the refurbishment is performed, only a small number of the devices are refurbished, thereby reducing the labor and cost involved in the refurbishment.

As a means for performing such a small-scale renovation without changing the entire game console, a means in which only the front door 2 is replaced has been proposed. By taking such a means, a portion where the player touches the gaming table or a portion which is in the player's field of view is renewed, and the appearance of the gaming table can be changed.

However, in recent slot machines, those equipped with the liquid crystal display device 13 are becoming the mainstream, and the effect contents displayed on the liquid crystal display device 13 are important factors for the player in progressing the game. However, in the refurbishment using the above-mentioned means,
It is impossible to renew the display contents of the liquid crystal display device 13.

That is, when the conventional slot machine 1 having the above-described configuration is newly installed using such means, the main control board 15 mounted in the housing 14 is also changed.
It is necessary to change the display control circuit for controlling the display of the liquid crystal display device 13. Therefore, in the conventional slot machine 1 described above, not only is the labor and cost required for the refurbishment not completely reduced, but also with the refurbishment in which only the front door 2 is replaced,
Since the display control circuit of the liquid crystal display device 13 cannot be changed, the display content of the liquid crystal display device 13 has not changed from the conventional one, and it has not been possible to give the player freshness.

[0010]

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and a variable display device which can be observed from the front of a device for variably displaying a plurality of symbols, and a game winning by random number lottery. A main control circuit including a prize mode determining means for determining a mode and variable display control means for controlling variable display of symbols based on the prize mode determined by the prize mode determining means; In a slot machine comprising a display device for displaying the obtained various information and a display control circuit for controlling the display of the display device, the display control circuit is mounted on a board attached to the rear side of the front door. It is characterized by comprising.

According to this configuration, when the front door is replaced for a small-scale renewal of the slot machine and the appearance thereof is changed, the display control circuit of the display device is integrated in the front door. Therefore, the display control circuit can be replaced with a new circuit together with the front door.

In the case where the slot machine is provided with a speaker for outputting a sound effect, and a sound output control circuit for controlling the output of the speaker is provided on a board attached to the rear side of the front door, At the time of new installation, the sound output control circuit of the speaker can be replaced with a new circuit together with the front door.

In the case where the main control circuit is formed on a board attached to the inside of the rear surface of the housing for housing the equipment, the display control circuit and the sound output control circuit are replaced by a new circuit when newly installed. In exchange, the main control circuit can use an existing circuit.

[0014]

Next, an embodiment of a slot machine according to the present invention will be described.

FIG. 3 shows a slot machine 2 according to the present embodiment.
1 is a front view of FIG.

Behind the front door 22 of the slot machine 21, three reels 23, 24, 25 are rotatably provided. On the outer peripheral surface of each of the reels 23, 24, and 25, a symbol row including a plurality of types of symbols (hereinafter, referred to as symbols) is drawn. These symbols are used in the slot machine 21
Are observed through the display windows 26, 27, and 28 in front of the camera. On the lower right side of the display windows 26, 27, 28, a slot 29 is provided for a player to insert a medal.

The display windows 26 to 28 have three horizontal windows (center L1).
And two diagonal lines (diagonally lower right L3A, diagonally right upward L3B). Prior to the start of the game, when the player inserts one medal into the medal slot 29, each of the reels 23 to
Only the center pay line L1 on the line 25 is activated as shown in FIG. When two medals are inserted into the insertion slot 29, the upper and lower prize lines L2A,
L2B is added, and the three horizontal pay lines L1, L2A and L2B are activated as shown in FIG. When three medals are inserted into the insertion slot 29, all the winning lines L1, L2A, L2B, L3A and L3B
Are activated as shown in FIG.

The circles in FIG.
25 represents the symbol drawn on the top. The activation of such a winning line is displayed to the player by turning on an activation line display lamp 43 arranged at the end of each winning line.

On the lower left side of the display windows 26 to 28,
A 1-BET switch 30, a 2-BET switch 31 and a MAX-BET switch 32 are provided. When a medal is credited in the credit amount display section 33, these 1
By operating the push buttons of the BET switch 30, the 2BET switch 31 and the MAX BET switch 32, one, two and three medals are bet in one game, respectively. The number-of-credits display section 33 is composed of 7-segment LEDs of a number corresponding to the number of digits of the numerical value to be displayed, and displays the number of medals currently credited.

Below the BET switches 30 to 32, a credit / payment changeover switch (C / P switch) 3
4 and a start lever 35, and a stop button 36,
37 and 38 are provided. The credit / payout of the medal (PLAY CREDIT / PAY OUT) can be switched by operating the push button of the C / P switch 34.

The operation of the start lever 35 causes the reels 23, 24 and 25 to simultaneously start rotating. The stop buttons 36, 37, 38 are
4 and 25, and these reels 2
When the rotation of 3 to 25 reaches a certain speed, the operation is activated, and the rotation of each reel is stopped according to the push button operation of the player.

Further, a sound transmission hole 39 and a medal tray 40 are provided in a lower part of the front of the slot machine 21. The sound transmission hole 39 is for outputting sound generated from a speaker housed inside the device to the outside. The medal receiving tray 40 stores medals paid out from the medal payout exit 41. At the top front of the slot machine 21, there is provided a payout display section 42 indicating how many medals are paid out for each winning.

A liquid crystal display device 44 is provided on the front door 22 below each of the reels 23, 24, 25. The liquid crystal display device 44 is a display device for rotatingly displaying the reels 23, 24, and 25, displaying a game history, and performing an effect during a bonus game.

FIG. 5 is a rear perspective view of the front door 22. The liquid crystal display device 44 includes a liquid crystal unit 44a, and the liquid crystal unit 44a is electrically connected to a liquid crystal control board 46 by a flexible flat cable (FFC) 45. The electrical connection between the FFC 45 and the liquid crystal control board 46 is made by a connector 47. The liquid crystal control board 46 includes a display control circuit for controlling the display of the liquid crystal display device 44. The liquid crystal control board 46 is covered and protected by a transparent resin case 48.

FIG. 6A is a side view of the front door 22, and FIG. 6B is a rear view of the front door 22. FIG. 7 shows FIG.
FIG. 8 is an enlarged view of the entire rear view shown in FIG.
FIG. 4 is a diagram in which a portion of a liquid crystal control substrate 46 shown in FIG. In these figures, the same parts as those in FIG. 5 are denoted by the same reference numerals, and description thereof will be omitted.

In each of these figures, a female connector 49 provided on the right side of the liquid crystal control board 46 is for electrically connecting a main control board to be described later and the liquid crystal control board 46.

FIG. 9 shows a slot machine 21 according to this embodiment.
FIG. 3 is a block diagram showing a configuration of a main control circuit that integrally controls a game processing operation in FIG.

The main control circuit includes a microcomputer (hereinafter referred to as "microcomputer") 50 as a main component, and further includes a circuit for sampling random numbers. The microcomputer 50 includes a CPU (Central Processing Unit) 51 that performs a control operation according to a preset program,
It is configured to include a ROM (read only memory) 52 and a RAM (read / write memory) 53 as storage means. The CPU 51 includes a clock pulse generating circuit 54 for generating a reference clock pulse, a frequency divider 55, a random number generator 56 as random number generating means for generating a predetermined range of random numbers, and an arbitrary random number extracted from the generated random numbers. A random number sampling circuit 57, which is a random number extracting means, is connected.

The main actuator whose operation is controlled by a control signal from the microcomputer 50 is a reel 2
Stepping motors 7 for rotationally driving 3, 24, 25
5. Hopper 58 for storing medals and each reel 23
There is a reel back lamp 63 that illuminates the symbols drawn in the numbers 25 through 25 from behind. These are driven by a motor drive circuit 60, a hopper drive circuit 61, and a lamp drive circuit 62, respectively. These drive circuits 60 to 62
Is connected to the CPU 51 via an I / O port of the microcomputer 50. Each of the stepping motors 75 is excited in one or two phases by the motor drive circuit 60, and rotates once when a drive signal of 400 pulses is supplied.

The main input signal generating means for generating an input signal necessary for the microcomputer 50 to generate a control signal includes a start switch 35 S for detecting the operation of the start lever 35 and a medal insertion port 29. There is an inserted medal sensor 29S for detecting the inserted medal, and the aforementioned C / P switch 34. Also, the photo sensor 79,
There is also provided a reel position detecting circuit 64 for receiving the output pulse signal from the photosensor 79 and detecting the rotational position of each of the reels 23, 24, 25.

The photo sensor 79 is connected to each of the reels 23, 24, 2
A reset pulse is generated each time the motor 5 rotates once. This reset pulse is sent to the CPU via the reel position detection circuit 64.
51. In the RAM 53, each of the reels 23 to
Regarding 25, the count value corresponding to the rotation position within the range of one rotation is stored, and when receiving the reset pulse, the CPU 51 clears the count value formed in the RAM 53 to “0”. By this clearing process, a shift generated between the movement display of each symbol and the rotation of each stepping motor 75 is eliminated for each rotation.

Further, as the input signal generating means,
Reel stop signal circuit 65 and payout completion signal generation circuit 6
There are six. The reel stop signal circuit 65 includes a stop button 3
When 6, 37, 38 are pressed, the corresponding reel 23,
Generate a signal to stop 24, 25. Further, the medal detecting section 67 counts the number of medals paid out from the hopper 58, and the payout completion signal generating circuit 66 sets the medal count value actually paid out inputted from the medal detecting section 67 to the predetermined payout number data. When it reaches, a signal notifying the completion of the medal payout is output to the CPU 51.

In the ROM 52, the slot machine 21
Is stored as a sequence program, and a winning probability table, a symbol table, a winning symbol combination table, and the like are separately stored.

The winning probability table is stored in the sampling circuit 5
7 constitutes a random number classifying means for classifying the random numbers extracted in each of the winning modes, and stores data for partitioning a predetermined range of random numbers generated by the random number generator 56 into each of the winning modes. Such a winning probability table is configured, for example, as shown in FIG. A1 to a3, b1 to b in FIG.
3, c1-c3, d1-d3, e1-e3, f1-f
3, g1 to g3 are preset numerical data, and are used when the random number extracted by the sampling circuit 37 is divided into each winning mode. This data is “a1 to g1” when the number of inserted medals is one, and “a1
In the case of three sheets, a combination of numerical values of "a3 to g3" is used.

These numerical values are usually expressed as “a <b <c <d <e <
f <g ”and the extracted random number value is a
If it is less than, it will be a jackpot winning (big hit) and "B
B "Winning flag is set. If the extracted random number value is equal to or larger than a and smaller than b, a medium winning prize (medium hit) is set, and the “RB” winning flag is set. If the extracted random number value is b or more and less than e, a small hit prize (small hit) is obtained. In this case, if the value is b or more and less than c, a “watermelon” winning flag is set. Indicates a "bell" winning flag, and if not less than d and less than e, a "cherry" winning flag is set. When the extracted random number value is equal to or more than e and less than f, a “re-game” winning flag is set. If the extracted random number value is equal to or more than f and less than g, a “special game” winning flag described later is set, and if it is equal to or more than g, a “losing” winning flag without winning is set.

In other words, the winning mode is determined by which numerical range one sampled random number belongs to, and is represented by a total of eight types of winning flags including "losing" and "replay". Here, the random number generator 56, the sampling circuit 57, the winning probability table, and the microcomputer 50 constitute a winning mode determining means. Since various types of hits are generated with a probability according to the data setting of the winning probability table, the total medals within the business hours of one day are not extremely influenced by the skill of the player. Payment rates remain almost constant.

The symbol table is conceptually shown in FIG. This symbol table is provided for each reel 23-2.
5 is associated with a symbol and the symbol row is represented by a symbol. In this symbol table, a symbol code corresponding to the code number is stored for each of the reels 23 to 25. The code number is
The reels 23 to 25 are sequentially provided at fixed rotation pitches based on the rotation position at which the reset pulse is generated. The symbol code indicates a symbol provided corresponding to each code number.

In the winning symbol combination table,
The symbol code of each winning symbol combination shown in the payout display section 42, the symbol code of the symbol combination forming the "reach eye" that suggests to the player that the flag of the occurrence of the specific game is established, and each winning is shown. A winning determination code, a winning medal payout number, and the like are stored. The winning symbol combination table is referred to at the time of stop control of the first reel 23, the second reel 24, and the third reel 25, and at the time of confirming a winning after stopping all the reels.

The types of game states in the slot machine according to the present embodiment include “RB operation”, “general game during BB operation”, “general game”, “general game during RB inside”, and “ There are a total of five types of “general games in BB inside”.

RB means the above-mentioned regular bonus game. In this RB game, a bonus game in which a plurality of high payout games are combined can be performed once.
“RB RUNNING” indicates a game state during this RB game, and either a loss or a JAC win occurs. BB means the above-mentioned big bonus game, and in this BB game, a set of a general game and the above-mentioned bonus game can be performed a plurality of times. "BB
The "operating general game" means this general game in the BB game, and in this general game, a small winning prize occurs with a high probability. The “general game” is a game state in which neither BB nor RB wins. In the “general game with RB inside winning” and the “general game with BB inside winning”, a predetermined winning symbol combination is not stopped and displayed on each of the reels 3 to 5 although the RB winning flag and the BB winning flag are set. , Indicates a general game state in which the player has not yet entered the RB game or the BB game.

As shown in FIG. 9, the CPU 51 is connected to a sub-control circuit 200 to which a speaker 59 is connected.
4 is connected to the image control circuit 300.
The image control circuit 300 controls display of an image to be displayed on the liquid crystal display device 44, and the sub-control circuit 200
In addition to controlling the sound output of No. 9, a process of selecting an image effect pattern of the image display control performed by the image control circuit 300 is performed.

FIG. 12 shows a slot machine 2 of the present embodiment.
1 is a block diagram showing an overall circuit configuration for controlling a game processing operation in FIG.

The main control circuit 100 is the circuit shown in FIG. 9, and the sub-control circuit 200 and the image control circuit 300 represent the inside of these circuits shown in FIG.

The sub control circuit 200 includes a sub CPU 20
1, a microcomputer circuit comprising a program ROM 202 and a control RAM 203. Sub CP
U201 is controlled by the control RAM 20 according to the sequence program in which the processing procedure is stored in the program ROM 202.
3 is used as a working area for temporarily storing data to perform predetermined arithmetic control.

That is, the sub CPU 201 is connected to the main control circuit 10 through the input port (IN PORT) 204.
The sound source IC 206 and the power amplifier (AMP) 207 are controlled in accordance with an instruction input from 0, and sound effects such as a medal insertion sound, a start lever operation sound, a stop button operation sound, a game sound during a big bonus, and the like are output from the speaker 59. Output. Further, the sub CPU 201 fetches information such as the game state at that time and the type of the winning flag determined by the winning mode determining means from the main control circuit 100 via the input port 204, and displays an image based on the fetched gaming state and the winning flag. An image effect pattern of the image display control performed by the control circuit 300 is selected.

For example, if the loss winning flag is set during a general game, a regrettable effect pattern indicating that the probability lottery result is not desired is selected, and the BB winning flag is selected during the general game. Is displayed, as a result of the probability lottery, a pleasing effect pattern that indicates that an internal hit has occurred is selected. The selected effect pattern is output to the image control circuit 300 via the output port (OUT PORT) 205.

Further, the image control circuit 300 controls the image control C
PU 301, program ROM 302 and control RAM
It is controlled by a microcomputer circuit 303.
The image control CPU 301 performs predetermined arithmetic control according to a sequence program in which a processing procedure is stored in the program ROM 302, using the control RAM 303 as a working area for temporarily storing data.

That is, the image control CPU 301 controls the sub control circuit 2 via the input port (IN PORT) 307.
In accordance with the instruction input from 00, the image control IC 304 is controlled to display an image of the designated effect pattern on the liquid crystal display device 44. At this time, the image control IC 304 includes a character ROM 305 in which character data is stored and a video RA which is a memory for displaying a color display.
Image display is performed using M306.

In this embodiment, the main control circuit 100 and the sub control circuit 200 are provided with the reels 23 to 25 in the same manner as in the conventional slot machine 1 (see FIG. 2).
On the main board mounted inside the rear surface of the housing above. However, the image control circuit 300 does not
The liquid crystal control board 46 is mounted on the rear surface of the liquid crystal display as shown in FIG.

Therefore, according to such a configuration according to the present embodiment, when the front door 22 is replaced by a small-scale renewal of the slot machine 21 to change its appearance, the display control of the liquid crystal display device 44 is performed. The image control circuit 300, which is a circuit, can be replaced with a new circuit together with the front door 22. Therefore, unlike the conventional slot machine 1, there is no need to replace the main control board mounted in the housing and replace the display control circuit for controlling the display of the liquid crystal display device. Therefore, according to the slot machine 21 of the present embodiment, the labor and cost for the refurbishment are thoroughly reduced.

In the present embodiment, the main control circuit 1
00 and the sub-control circuit 200 are configured on the main control board attached to the inside of the rear surface of the housing that accommodates the device, so that when the image control circuit 300 is newly installed, the main control circuit is replaced with a new circuit. Conventional circuits can be used for 100 and the sub-control circuit 200. Therefore,
Also in this regard, the slot machine 2 according to the present embodiment
According to (1), the labor and cost for the refurbishment are thoroughly reduced.

In the above embodiment, the case where the sub-control circuit 200 is formed on the main control board inside the rear surface of the housing has been described.
Alternatively, the liquid crystal control board 46 on the rear side of the display device 2 may be configured together with the image control circuit 300.

In such a configuration, a circuit for selecting the type of information to be displayed on the liquid crystal display device 44 and a sound output control circuit for controlling sound output from the speaker 59 are also provided on the rear side of the front door 22. Because it is configured on an attached board,
At the time of refurbishment, the display information selection processing circuit and the speaker 59
Can be replaced with a new circuit together with the front door 22. Also, at the time of refurbishment, the image control circuit 3
The main control circuit 100 can use an existing circuit while replacing the 00 and the sub-control circuit 200 with a new circuit. Therefore, even in such a case, the same operation and effect as in the above embodiment can be obtained.

In the above embodiment, the case where the display device provided on the front side of the front door 22 for displaying various information is the liquid crystal display device 44 has been described. It is not limited to 44. For example, a display device such as a dot matrix LED (light emitting diode), a CRT (cathode ray tube), and a plasma display device may be used. Furthermore, each reel 23 ~
25 may be a fourth reel variably displaying three columns of symbols variably displayed and another column of symbols.
In each of these cases, the same operation and effect as those of the above-described embodiment can be obtained.

[0055]

As described above, according to the present invention, when the front door is replaced for a small-scale renewal of a slot machine to cause a change in its appearance, the display control circuit of the display device is provided on the front door. Since the display control circuit is integrated, the display control circuit can be replaced with a new circuit together with the front door. If the slot machine is provided with a speaker that emits sound effects and the sound output control circuit that controls the sound output from this speaker is configured on a board attached to the back side of the front door, the slot machine may be used for new installation. In addition, the sound output control circuit of the speaker can be replaced with a new circuit together with the front door. For this reason, the labor and cost for the refurbishment are thoroughly reduced.

In the case where the main control circuit is formed on a substrate attached to the inside of the rear surface of the housing for housing the equipment, the display control circuit and the sound output control circuit are replaced by a new circuit when newly installed. In exchange, the main control circuit can use an existing circuit. Accordingly, also in this respect, the labor and cost for the refurbishment are thoroughly reduced.

[Brief description of the drawings]

FIG. 1 is a front view showing the appearance of a conventional slot machine.

FIG. 2 is a front view showing the internal structure of a conventional slot machine.

FIG. 3 is a front view showing the appearance of the slot machine according to one embodiment of the present invention.

FIG. 4 is a view showing a state in which a winning line written on a display window of the slot machine according to the embodiment of the present invention is sequentially activated.

FIG. 5 is a rear perspective view of a front door of the slot machine according to the embodiment of the present invention.

FIG. 6 is a view showing a side surface and a back surface of the front door of the slot machine according to the embodiment of the present invention.

FIG. 7 is an enlarged view of the entire rear surface of the front door shown in FIG. 6;

8 is a partially enlarged view of a part of a liquid crystal control board attached to the back of the front door shown in FIG.

FIG. 9 is a block diagram showing a configuration of a main control circuit of the slot machine according to one embodiment of the present invention.

FIG. 10 is a view showing a winning probability table used in a game process of the slot machine according to the embodiment of the present invention.

FIG. 11 is a view showing a symbol table for associating the rotation position of each reel with a symbol, which is used in the game processing of the slot machine according to the embodiment of the present invention.

FIG. 12 is a block diagram showing an overall circuit configuration for controlling a game processing operation in the slot machine according to one embodiment of the present invention.

[Explanation of symbols]

 21 slot machine 22 front door 23, 24, 25 first, second and third reels 26, 27, 28 window 29 medal slot 30, 31, 32 BET switch 33 credit number display section 34 ... Credit / payment changeover switch 35... Start lever 36, 37, 38. Stop button 39... Sound-transmitting hole 40. Medal receiving tray 41. Medal payout exit 42. Payout display 43. Validation line display lamp 44. ... Liquid crystal control board 59 ... Speaker 100 ... Main control circuit 200 ... Sub-control circuit 300 ... Image control circuit

Claims (7)

[Claims] 1. A variable display device which is viewed from the front of a device for variably displaying a plurality of symbols, a winning mode determining means for determining a winning mode of a game by random number drawing, and a winning mode determined by the winning mode determining means. A main control circuit configured with variable display control means for controlling the variable display of the symbols based on the symbol, a display device for displaying various information provided on the front side of the front door, and controlling the display of the display device. A slot machine comprising a display control circuit, wherein the display control circuit is configured on a substrate attached to the back side of the front door. 2. The slot machine according to claim 1, wherein the main control circuit performs a process of selecting a type of information to be displayed on the display device. 3. The slot machine according to claim 1, wherein the selection processing of the type of information displayed on the display device is performed by the display control circuit. 4. A speaker for producing a sound effect, wherein a sound output control circuit for controlling the output of the speaker is provided on the board attached to the rear side of the front door. The slot machine according to claim 1. 5. The slot according to claim 1, wherein the main control circuit is formed on a substrate attached to the inside of the rear surface of a housing for housing the device. Machine. 6. The slot machine according to claim 1, wherein the display device is a liquid crystal display device. 7. The variable display device according to claim 1, wherein the symbol is variably displayed in three rows, and the display device further variably displays the symbol in another row. Item 3. The slot machine according to item 1.