How does a washing machine's direct drive work?

Anyone who's watched TV commercials knows about direct-drive washing machines. Korean brands are especially popular. But few people know what this design is and why this type of appliance is so popular right now. What's the basic structure of a direct-drive washing machine, and is this system truly reliable?

Design features

Direct-drive washing machines are designed with a motor attached directly to the drum. This is achieved without the use of a belt or pulley, using a special clutch instead. This clutch is the mechanism that drives the gearbox. This machine is more compact than its counterparts, as it lacks additional components.

Typically, such washing machines use a three-phase brushless motor. This equipment has a permanent magnet rotor and a stator, which is equipped with 36 induction coils. The rotor is attached directly to the drum, meaning the rotor shaft is also the drum shaft itself. The motor is controlled by signals sent from the electronic module.

Comparison with old technology

Standard washing machines use a belt drive to rotate the drum. The drum is connected to a pulley, and the belt supplies torque from the motor shaft. This type of machine has a weak point: the belts wear out quickly and need to be replaced frequently. Furthermore, the washing machine vibrates and makes a lot of noise during the washing and spin cycles.

Washing machines equipped with a direct drive are distinguished by the fact that the motor has no contact points, such as brushes or belts. This makes the motor much more reliable and durable.

Important! To determine whether the appliance is equipped with a direct drive, carefully examine the case. A special sticker will be located on the front side that says "Direct Drive."

A washing machine of this type can “afford” a larger drum and a more powerful motor, due to the fact that there is more free space in the body.

While a traditional washing machine concentrates the cleaning process on the lower half of the drum, direct-drive machines remove dirt through the drum's back-and-forth motion. This results in more efficient and even cleaning of laundry.

What are the advantages and disadvantages of direct drive?

The direct drive system has many positive qualities. We'll list the most obvious ones now.

1. This design is more reliable, as it contains fewer fragile parts or components that wear out quickly. For example, LG offers a 10-year warranty on its motors, as they are absolutely confident in the quality of their equipment.
2. This type of equipment operates virtually silently, producing only a slight rustling sound from the movement of the laundry being washed in the drum.
3. The operation of the drum in this technique is maximally balanced, so the laundry is distributed evenly in the metal container.
4. The machine barely vibrates during operation, which improves washing results. Laundry is washed evenly, without concentrating on a specific part of the drum.
5. The engine does not require as much attention from technical specialists.
6. This technology automatically detects the weight of items in the drum, finds the appropriate mode, and allows you to save resources: water and electricity.

But direct drive also has some drawbacks. Some are tolerable, but others are alarming.

• The price of the equipment itself and its components is quite high. For the price of such a device, you could buy a high-quality machine of a classic design. This stems from the complex design of the module that controls the machine's movement.
• Direct drive is vulnerable to voltage surges. This is why experts recommend using voltage stabilizers.
• There's a small chance that water could leak through a worn oil seal and enter the engine, causing damage to the unit. This isn't covered by the warranty, so it's important to replace the oil seal more frequently to avoid catastrophic consequences.
• The flushing and filling of water is quite noisy, which some customers complain about.

The bearing assembly in these machines is not very well designed. Future engineers will need to work on improving its wear resistance.

   

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