The design and operation of power tools can significantly impact their performance and lifespan. Although brushless direct current (DC) motors have only recently been incorporated into power tools, they have been technologically active for several decades. The origin of brushless DC motors can be traced back to the 1960s, when they were primarily used to power conveyor belts. It was not until 2003 that their application was extended to industrial machinery, and subsequently, in 2009, they found their way into the power tools segment. These motors brought about significant improvements in the functioning of conventional brushed motors. Both motors transform electrical energy into mechanical force; however, distinct variations exist in their efficiency, price, and upkeep needs.
Understanding Brushed Motor Functioning
For a clear comprehension of how brushless motors operate, it is beneficial to first explore the functioning of their brushed counterparts, a technology in application from the late 19th century until the advent of brushless motors.
Brushed motors are composed of four fundamental components:
- Stator: The motor’s stationary section housing permanent magnets that facilitate rotor movement.
- Rotor: Also referred to as the armature, this rotating component contains a copper coil that acquires electromagnetic properties when powered.
- Commutator: This metallic ring aids continuous rotor spinning by altering the polarity with every semi-turn of the rotor.
- Brushes: These are made of carbon and are directly connected to the power source. They transfer power to the commutator ring, thus activating the rotor.
The constant contact of the carbon brushes with the spinning commutator results in considerable friction. This is where the key differentiation arises between the conventional motor technology and the more recent brushless motor technology.
Decoding Brushless Motor Functioning
Contrary to brushed motors, brushless ones lack any physical commutator or brushes. Instead, brushless motors depend on magnets and an electronic circuit for power generation and connecting the stator and rotor. This structural design eradicates the friction usually encountered in a brushed motor, leading to several benefits, which include:
Increased Responsiveness
Often called ‘smart motors,’ brushless motors have computer chips and internal sensors. These adjust the motor’s speed, torque, and power supply per the task requirements. For instance, when using a brushless tool to insert a nail into a drywall versus a denser material, the motor’s electronic circuitry modulates the power used, making it efficient for the job.
Reduced Heat Generation
Heat can considerably degrade the longevity of motors and batteries. Brushless tools operate at cooler temperatures than their brushed counterparts since the heat-generating winding mechanism is located on the tool’s exterior rather than the interior. Reduced friction results in less heat.
Decreased Maintenance
Brushless power tools outlive brushed ones due to the absence of brushes that require replacement. For brushed power tools, replacement brushes are needed approximately every two to seven years. The frequency depends on the working environment and operating temperatures as friction wears down the brushes rapidly. Brushless tools also have a better defense mechanism against dust and debris due to the lack of need for cooling air vents, thanks to reduced heat generation.
Compact, Light, and Quiet Operation
The omission of brushes and commutators makes brushless tools lighter and more compact, enabling usage in confined spaces. Decreased friction and vibration allow these tools to operate quietly and comfortably over extended durations. Additionally, brushed motors can produce sparks during operation, which can be hazardous; hence, brushless motors are often favored under such conditions.
Enhanced Efficiency
As per a study by Consumer Reports, brushless motor vs brushed ones showcase better energy efficiency than brushed ones, often running on battery power up to 50% longer. The lack of brushes that typically lose energy to friction contributes to the extended battery life of brushless tools. Some models can even function for several hours at a stretch.
Financial Implications
Brushless power tools generally cost around 30% more than brushed tools. This price difference is largely due to the intricate electrical systems within the stator. The choice between a brushed and brushless tool is contingent on the nature of its usage. Brushed power tools, while cost-effective, operate at a constant speed, making them suitable for lighter tasks. Nevertheless, if you are a professional who frequently uses power tools or for heavy-duty jobs, a brushless tool might be a more fitting choice, providing better efficiency, speed, and tool lifespan.
This in-depth comparison of “brushless motor vs brushed” elucidates the distinctive characteristics of each type. When selecting a power tool, the key factors to consider include cost, expected lifespan, and the nature of the tasks it will be employed for. Understanding the operational mechanics of brushed and brushless motor vs brushed enables informed decisions when choosing the right power tools for your needs.”
