Ogura power-off brakes
Power-Off (Spring-Applied) Holding Brakes
Power-off brakes hold or stop a load whenever electrical power is lost or switched off – once called “fail-safe” brakes. Ogura’s range runs from brakes the size of a coin for servo motors to large brakes for lifts and hoists.
- 2 – 800 NmRNB, MNB, SNB ranges
- 24 / 90 Vstandard coils
- zerobacklash options
- manualrelease options
The range
The Power-Off Brake Range
MB Micro Brakes
Tiny holding brakes for servo motors, robots and medical equipment, round or square.
- Holding and e-stop
RNB Brakes
Spring-applied brakes for holding and e-stop; zero-backlash RNB-Z option.
- 2 – 200 Nm
- 24 / 90 V
MCNB-T and RNB-T
Ultra-thin holding brakes to shorten the motor-brake package.
- 2 – 50 Nm
MNB Brakes
Spring-applied brakes for stopping and holding, with adjustable torque.
- 2 – 800 Nm
SNB Brakes
Large friction disc for many trouble-free stop cycles.
- 1 – 100 Nm
PMB Permanent Magnet
Magnets apply the brake – smaller, lighter, zero backlash and a softer stop.
- 0.4 – 120 Nm
How it works
How It Works
Power Off: Braked
Springs push the pressure plate against the friction disc, clamping it between the pressure plate and cover. The disc is keyed to the hub on your shaft, so the load is held.
Power on: Released
Power to the coil pulls the pressure plate back against the springs, opening an air gap so the disc turns freely with the shaft.
Why Ogura holding brakes
Safe When the Power Goes
Small Profile
High torque in a compact, thin package.
Zero Backlash
Options for registration and servo axes.
Fast Response
Short pressure-plate travel for quick engagement.
Adjustable
MNB brakes have adjustable torque; manual release on larger units.
How to choose
Choosing a Holding Brake
Hold or Stop?
Holding-only brakes are for holding and e-stops; others are rated to stop a moving load.
Torque and Size
Motor frame size and holding torque set the model.
Voltage
24 and 90 V are standard; others are available.
Release
Manual release levers are available for many models.
Literature & related
More Information
- Power-off brakes
MB, RNB, MCNB-T, MNB, SNB and PMB holding brakes · PDF, 3.9 MB
Not Sure Which One You Need?
Tell us about the job – the machine, the conditions and what it has to do – and we’ll help you choose the right Ogura product.