Summary:

I was part of a team that designed a compact brake to meet strict size and torque limits while minimizing axial length and weight. The brake also needed to engage when power was cut so it could function with emergency stop systems, unlike most electromagnetic or electrostatic brakes that only operate when powered. Our team addressed this by developing a wrap spring clutch brake architecture. Because wrap spring mechanisms transfer torque efficiently, only a small tang force is required to release the spring compared to the torque the brake can hold. By optimizing the spring geometry and the internal tang capture blocks, the team created a compact brake that met both the torque and size constraints while engaging when power was removed.

Patent No.: US 11,732,768 В2

Date of Patent: Aug. 22, 2023

FAILSAFE BRAKE DEVICE FOR ROBOTIC AND OTHER APPLICATIONS

Patent Abstract:

A variety of brake and/or clutch mechanisms, and improvements thereof, are provided having improved braking power, reduced size and weight, and other benefits. The braking mechanisms include a wrap spring clutch that is operable to mechanically couple a rotating member to a brake rotor that is in consistent contact with a brake pad. Actuation of the wrap spring clutch allows the wrap spring to engage with the rotating member, coupling the rotating member to the brake rotor thus braking the rotating member. The combination of the wrap spring clutch with the brake rotor and pad provides an overall braking mechanism that exhibits the decreased power cost, weight, size, and engagement time of the wrap spring clutch while having a braking power that can be moderated by specifying the area, engagement force, coefficient of friction, or other properties of the brake rotor and pad.