Electromagnetic Shaft Brakes
Electromagnetic shaft brakes use electrical actuation but transmit torque mechanically. EM brakes feature three main components: a field coil made of copper or aluminum, an armature and a hub. The coil is housed in a carbon steel shell and is held in place using either epoxy or a bobbin. When voltage is applied, the coil becomes an electro magnet and creates a flux that pulls the armature to the hub. The armature then creates friction that can be used to slow or stop rotational motion. When the electrical voltage is removed, springs hold the armature away from the hub and a small gap of air forms to allow rotation to continue.
Most EM brakes use a single plate friction surface to slow or stop motion, but other configurations are available. The addition of friction material is also common in industrial applications to reduce the amount of wear on the brakes, especially in high cycle equipment.
The amount of time it takes to develop the magnetic field and the stopping time are both determined by the strength of the magnetic field, the amount of inertia and the size of the air gap between the armature and the hub. Temperature changes can also influence the amount of torque created by an EM brake.
Electro magnetic brakes are used in virtually every industry and for a wide range of applications. Some of the common uses for electromechanical shaft brakes include:
- Industrial motors and equipment
- Robotics, servo motors and automation equipment
- Amusement park rides
- Packaging and food processing equipment
- Elevators and escalators
- Automotive braking systems
Electromagnetic Brakes Provide Reliable Holding and Braking for Precision Applications
Mikey Pulley manufactures shaft brakes in different electromechanical styles and configurations to meet the requirements of virtually any application. Mounting options for our electromagnetic shaft brakes include shat-mounted brakes for use in axial braking applications and rotor-mounted shaft brakes for mounting directly onto an inertial body. Important considerations in selecting the right electromagnetic brake for your application include: required torque, performance, load properties and drive force.
Electromagnetic Micro-Brakes have a compact design for use in small precision equipment such as ATMs, copy machines and optical machines where fluctuations in torque and response need to be avoided.
Miki Pulley EM micro-brakes are available in three different armature options and provide friction torque up to 2.4Nm, depending on the style chosen. They are suitable for operation in ambient temperatures up to 104°F and provide zero backlash.
Actuated Brakes are ideal for applications requiring sudden stops and are offered in shaft or flange mounting styles. Common applications include printing, paper processing, packaging and textile applications.
Our 111 model provides a standard configuration with three armature options, and the BSZ model offers a slimmer profile design and two armature styles. Miki Pulley actuated electromechanical brakes operate in ambient temperatures up to 104°F, feature a zero backlash design and provide torque up to 320Nm depending on the model selected.
Spring Actuated Brakes feature compression springs that push the armature into the friction disk to stop rotational motion. This style of shaft brake provides exceptionally stable and reliable holding power is ideal for long-term holding applications.
Miki pulley provides spring actuated electromagnetic brakes in several styles, including slim profile designs, providing up to 55Nm of brake torque. Our electromechanical shaft brake models offer effective solutions for both standard and emergency braking and holding applications and operate in ambient temperature from 14°F to 104°F.
Electromagnetic clutch and brake combination units are offered in eight different configurations providing torque up to 320Nm. Our electromechanical shaft brake combo units include fully enclosed models, dual clutch and brake models, and models including a motor, reducer, clutch and brake.