A permanent-magnet eddy-current brake slows a moving mass with magnetic drag alone — no pads, no external power, no contact. It is one of the cleanest ways to shed speed.
How PM eddy-current brakes work
Permanent magnets and a conductive plate move past one another. That motion sets up small electrical currents — eddy currents — in the plate, and those currents create a magnetic field that pushes back against the motion. So the brake resists whatever is moving past it. Nothing touches and nothing rubs. The braking force comes straight from the moving body's own energy, which turns into heat in the plate.
How the braking force behaves
The braking force changes with speed. It is strongest through the working speed range and can ease off at very high speeds. We tune the design so the strongest braking lands where your duty needs it.
Track-mounted vs vehicle-mounted magnets
Deciding which part carries the magnets is a trade-off between how much of the track carries magnets and how much weight each vehicle has to carry. Putting the magnets on the track keeps each vehicle light, but the magnets have to run along the whole braking zone. Putting the magnets on the vehicle needs only a plain conductive rail on the route, but every vehicle then carries the added magnet weight.
Magnets on the track
Conductive plate rides on the vehicle; magnets line the braking zone. Light passive vehicle, but you fit magnets over the full active length — often the better fit where braking is needed only in defined zones.
Magnets on the vehicle
Vehicle carries the magnet assembly and passes over a continuous conductive rail. Simpler track, but every vehicle carries the magnet mass.
See it in motion
A vehicle running into a permanent-magnet brake — the eddy currents do the retarding, with no contact.
Double-sided caliper arrangements
Placing magnets on both sides of the plate — a caliper arrangement — brakes it from each face and lets the pull from each side largely balance out. For a given size, this gives markedly more braking force than a single side. It is the natural choice where you need strong, compact braking without a heavy supporting frame.
No-power dynamic braking
The brake needs no power while it works, which makes it well suited to fail-safe and emergency duty — there is nothing to switch on before it acts. There are no friction pads to wear out or fade, so repeated braking does not wear the braking surfaces the way a mechanical brake does. The energy has to go somewhere, though: it becomes heat in the plate, so we plan the cooling as part of the design.
Zero-speed holding caveat
One thing to plan for: the brake gives no force at a standstill. With nothing moving there are no eddy currents, so there is no braking. It is excellent at shedding speed but cannot hold a load still. Where you need to hold at rest — parking on a slope, waiting at a station, holding a launch sled — pair it with a mechanical holding brake that takes over once the vehicle has slowed or stopped.
How we prove a design
Because the braking energy turns into heat, we check that both the plate and the magnets stay safely within their temperature limits for your duty. We size the brake with proven engineering models, confirm the force and heat with detailed simulation, and check it against your route before we build anything.
Related
Need contactless braking sized to your duty?
Tell us the mass, speeds and stops, and we will model the force, the thermal path and the holding strategy.
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