Before we get into how ice makers work, let’s touch briefly on how man made refrigeration is achieved.
I’ve attached a quick four minute video which explains the process in fairly simple terms:
Moving on, the two broad categories of ice making machines are consumer and industrial. Those of the consumer variety are further divided into two sub-types.
The first sub-type is a compartment integrated into refrigerators such as the one you find in the freezer at home. The other is a stand alone, and usually portable device which creates ice on a larger scale than the ones than come with your refrigerator.
The other broad type is an industrial machine which makes ice on an even larger scale for businesses which either sell it or have a demand for it in large quantities. This piece of equipment is usually very heavy and lacks portability.
How Do Integrated Home Ice Makers Work?
As you may guess, this type is the simplest type of ice maker there is. It works by using a repeated process which starts with the activation of a water valve by a timer which causes water to fill an ice mold.
Next, a thermostat uses the temperature and the time since the water was poured to activate a heating element which causes the mold to soften the edges of the ice cubes so they can be removed easily. If the heating element isn’t included in the process or malfunctions, the ice will stick to the mold.
After the softening of the edges, a shaft equipped with small arms and powered by a motor scoops the cubes and places them into a storage bin.
While the shaft is placing the ice cube into the storage bin, it also raises a shut off arm which is used to stop the machine from making any more ice. Without this arm, the ice making cycle would continue into perpetuity.
After the shaft has successfully placed the ice cube into the storage bin, the shut off arm falls back into the storage bin. If it falls to a level indicating that there is more room for ice, the process will repeat itself until full. The user can also lift the shut off arm to cease ice production.
How Do Portable Ice Machines Work?
The portable variety has a slightly different philosophy behind how the ice is created. Instead of filling a mold with water and waiting for it to freeze from the outside in, a portable ice machine freezes the water directly using metal prongs poking out from the heat exchanger. This allows the water to be frozen directly, and therefore creates ice quicker.
The process starts when water is poured directly into the reservoir. The water is then pumped into a freeze tray near the top of the unit and the metal prongs are lowered into the tray.
The temperature of the prongs fall very quickly and the water subsequently begins to freeze; starting with the water directly on the prongs and expanding out. The longer the prongs are left in the water, the larger the bullet shaped ice pieces will be.
When the ice nuggets reach a certain size, remaining water in the tray is drained back into the reservoir to be reused. Before the process repeats, however, the temperature of the metal prongs is raised slightly so that the ice bullets can slide off and fall into the storage basket of the device.
A sensor monitors the level of ice and stops the cycle is if the container is full.
Another product of portable ice makers is sonic ice; the creation of which is explained below.