These more efficient and durable power tools are invading the DIY market. So how do they work?
Gear-obsessed editors choose every product we review. We may earn commission if you buy from a link. Why Trust Us? brushless motor dc
In the world of power tools, brushless motors are all the rage. While the technology isn't exactly new, it has gained traction in recent years due to some high-profile releases by Makita, Milwaukee, DeWalt, and others.
🛠You love fixing stuff. We love fixing stuff. Let's do it together.
"Brushless motors have been around since the 1960s, being used in industrial and manufacturing applications for [motors that drive] conveyor belts," Christian Coulis, senior vice president of product management at Milwaukee Tools, tells Popular Mechanics.
Makita, however, was the first company to use them in power tools. "[It was] first in our assembly division in 2003 for the defense and aerospace industries, and then again in 2009, when we released a brushless three-speed impact driver," Wayne Hart, Makita's communications manager, tells Pop Mech.
Manufacturers claim that brushless tools have added performance and durability and that they're smarter than the average tool. So what exactly is the technology behind these new motors?
A traditional brushed motor is made up of four basic parts: carbon brushes, a ring of magnets, an armature, and a commutator. The magnets and brushes are stationary, while the armature and commutator rotate together on the motor shaft within the magnets.
When the motor is energized, a charge travels from the battery, through the brushes, and into the commutator. (The brushes are spring-loaded to maintain physical contact with the commutator.) The commutator then passes the charge on to the armature, which is made up of copper windings (they look like bundles of copper wire). The windings are magnetized by the charge and push against the stationary ring of magnets that surround it, forcing the armature assembly to spin. The spin doesn't stop until the charge from the battery stops.
A brushless motor loses the brushes and the commutator. And the locations of the magnets and windings are reversed: The magnets are on the conventional motor shaft and the copper windings of the armature are fixed and surround the shaft. Instead of brushes and a commutator, a small circuit board coordinates the energy delivery to the windings.
Because the electronics communicate directly with the stationary windings, the tool adjusts according to the task—which is why the companies market these as "smarter" tools. For example, if you're using a brushless drill to drive screws into Styrofoam, it more readily senses the lack of resistance (compared with a brushed motor) and begins to pull only what little charge it needs from the battery. If the tool then starts putting 3-inch screws into mahogany, it will adjust accordingly and draw more current. By contrast, a brushed motor will always run as fast as it can while in use.
In addition, brushless motors can be more powerful overall. Because the copper windings are on the outside of the motor configuration, there is room to make them larger. Brushless motors also don't have the friction and voltage drop that brushes create by dragging against the spinning commutator. This physical contact results in a continuous energy loss during the operating process.
The net gain is a tool with greater efficiency and more durable motors. So it goes without saying that every power tool will have a brushless motor in it by the end of the year, right? Not a chance, Milwaukee's Coulis says.
"While the benefits of brushless technology are vast, manufacturers encounter extreme cost barriers due to the added cost of the motor and electronics that it takes to manage the motor properly," she says. In other words, they're expensive, and so brushless motors are better suited to benefit pros who can shell out the big bucks for a tool that they're going to use every day. Brushless tools are approximately 30 percent more expensive to make than standard cordless tools, and the batteries to power them are typically out of reach for most DIYers.
But as battery technology improves and tool design advances, buyers will start seeing more and more brushless tools at their local home center. They're here to stay, but it will probably be a while before the technology filters down to all power tools for weekend DIYers.
The 31 Best Last-Minute Gifts for Men on Amazon
Amazon’s Portable Jump Starter Sale: Up to 50% Off
Save 40% on This Craftsman 20V 6-Tool Combo Kit
Save 38% on Powerful Cordless Leaf Blowers
Save Up to 61% on DeWalt Power Tools on Amazon
This Editor-Favorite Worx Snowblower Is 30% Off
The Best Cyber Monday Deals on Milwaukee Products
Lowe’s Cyber Monday Deals 2024
Save 30% on These Leatherman Multitools at Amazon
A Part of Hearst Digital Media
We may earn commission from links on this page, but we only recommend products we back.
brushless motor low rpm ©2024 Hearst Magazine Media, Inc. All Rights Reserved.