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How Does a Slot Machine Mechanism Work?

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Slot machines are one of the most popular and cheapest ways gamblers play their way to huge winnings. A player has to sit in front of the machine, put their money in, pull the level for the reel spin, and expect a win. Easy. But what really goes on after pulling the lever, and what are the odds of winning or losing? Let us explain what happens behind the scene every time you play slots in a casino.

Chances of winning

Land-based and online slot machines like you see at เว็บสล็อตใหม่ล่าสุด have the same operating principle. However, technology has added digitization to the online version. For example, digital machines can have up to 256 virtual symbols with millions of possible combinations, whereas physical slots online only have about 20 symbols per reel. Nonetheless, the chances of winning are based on some fundamental principles.

Random number generator

Each slot machine uses a random number generator — algorithm developers use it to ensure unexpected and unbiased outcomes. Each number is associated with a different combination of symbols. As a result, the chances of winning or losing depend on the number generated when you activate each play.

Casino bonuses

The chance of winning a slot game is higher with bonuses. Online and land-based casinos use free spins to encourage players to take specific actions. Although it is more of a marketing strategy, gamblers can try out a slot machine without risking any money. Players can get 5 – 100 spins over days, depending on the casino. With this, they can test different slots, play for free, and win real money.

Besides bonuses and random number generation, volatility and frequency also determine the chances of winning. Payout volatility tells how often you can expect a win on the reel, which can be high, medium, or low. High volatility games mean you can expect to win slots less often but have the highest payout, while low volatility means frequent but smaller payout.

The machine

Computer-controlled slots have replaced classical machines. However, the rules of gameplay are the same. To score on a slot machine, you need to pull a lever that rotates three reels or more with pictures on them. The odds of winning or losing depend on which image matches the pay line. Put differently; you win if each reel displays the same picture with the pay line.

Slot machines have various gears. A metal shaft connects to the handle mechanism, supports the reels, and is a central element to the system’s operation. A braking system also stops the spinning reel, and a sensor transmits the reel positions to the payout system. When a player slots the coin, a coin detector unlocks the brake so the gambler can move the lever.

Although the elements above summarize the dynamics of slot machine operation, manufacturers have different ways of operating them.

The slot machine handle

When a player pulls the machine’s handle, it rotates a hook mechanism that grabs the kicker, pulling it. A catch also moves and pivots a control cam piece forward. This action rotates some gears connected to the cam. A spring returns the control cam back to its position, and the gear assembly performs mechanical delay. The entire movement consists of interactions between the control cam, cam plate, notched discs, kicker, stopper, and kicker springs.

Unlike conventional slot machines, electrical slot machines run on motors and stoppers activated by solenoids. As a result, they are faster and have fancier sound and light displays. The outcome of each pull a player initiates is controlled by the central computer instead of the reel motion, and it uses step motors to control the reel to determine when the reel stops.

Slot machine payouts

Different types of slot machines use various payment systems. A simple example is a single coin machine. The slot device allows a player to activate all winning combinations with a coin. When a player inserts the coin, it drops into a case with a movable shutter connected to a metal linkage. Although the shutter is closed, when the slot machine hits the jackpot, the shutter opens, and coins fall from the device. The linkage holds the shutter. Therefore, the stopper must shift the linkage up in any scenario for coins to fall from the machine.

In electrical slot machines, the discs have metal contacts that engage a stationary contact wire when the reel stops. As a result, each stop closes a new switch in the electrical system. Some advanced machines also use photoelectric cells to detect positions, and the electronic circuit uses a light source to determine reel positions.


Slot machines are easy to play, as you don’t need to concern yourself about the technicalities. You only need to pick a game, place a bet, and spin reels. From a player’s perspective, all you hear is a clunk after pulling the handle, and the reels start spinning, oblivious to the many twists and turns happening within the device.