Tool manufacturers continue to add more safety and fatigue-reducing features to their products. Examples of auto-locking switches, auto-locking switches, blade guards, and guards abound — and that's just the beginning. One safety feature you might take for granted because you can't see it – electric brakes. Electric brakes are a premium feature on the best circular saws, and many others. This unique feature has saved many blades, wood floors, ropes, and even fingers or toes! A piece of sawdust or some obstruction can easily prevent the blade guard from falling back into place after a cut. Some saw blades can continue to spin for 10 seconds or more without an electric brake. An electric brake stops the blades in approximately 2 seconds. So how does a chainsaw's electric brake work to keep you safe?
quick summary
- The flip-flop releases the reverse current
- This type of braking uses electricity
- Mechanical brakes (more rare) stop the spinning wheels or blades almost immediately
- Electronic brakes wear out, but not as much as mechanical brakes
- Efficiency and braking speed may decrease over time – requires repair
Electric brakes may be technically difficult to implement, but the mechanism is easy to explain. It's really easy. are you ready? Here it comes:
When the trigger is released, the current reverses.
Yes. That's it. Reversing the current reverses the motor long enough to provide the friction needed to stop the spinning blade. As a result, the saw blade stops much faster than it can stop itself. It's easy to imagine the potential damage that could be caused by the blade spinning for 10-12 seconds after cutting – especially with larger, heavier saws. The same danger exists with circular saws and angle grinders, which can be put down while the blade is still spinning.
While some grinders have mechanical brakes that stop the spinning wheels or blades instantly, electric brakes (which make up most of these systems) rely on electricity to stop the blades.
This danger can be mitigated by using a saw with an electric brake whenever possible. If you're a purchasing decision maker for your company, or just buying tools for your own use, electric brakes are a feature you should stick with.
How long do chainsaw blade brakes last?
While electronic brakes don't wear as much as mechanical systems, they do wear out over time due to brushes and other factors. In either case, it is wise to monitor how long the blade has been spinning after the trigger is released. If the brake no longer stops the blade quickly, consider repairing or replacing the tool.
We also felt the need to point out how the brushless motor helps reduce blade speed. With brushless motors, there is a natural electrical friction whenever the circuit is de-energized. This tends to naturally slow down the spinning blade – even in the absence of specific blade braking circuitry. Because brushless motors already use advanced electronics anyway, you'll find that they'll usually go a step ahead and incorporate some sort of blade braking system to help slow the spinning blade once you let go of the trigger.
Safety first
Don't use electric brakes as your first line of defense. Operators always fill this role. Staying safe on the job site starts with your mindset. As with any tool, this mechanism and/or the blade guard may malfunction. The brakes serve only as a tailgate for careful use. An electric knife switch (or electronic brake) may be the invisible guardian for many businessmen. Make sure it stays in working order.
Now, when someone asks you, "How does a chainsaw's electric brake work?", you already know the answer. We want you to work more safely because of this. If you're a pro and have circular saw safety tips, add them in the comments below or drop a comment on Facebook, Instagram, or Twitter.