Abstract: What is presented is a mechanical arm assembly with a novel roller thrust bearing. The mechanical arm assembly comprises a first arm having a first end and a second end. A first roller thrust bearing is mounted to the first end and to a ceiling. A second roller thrust bearing mounted to the second end. Each roller thrust bearing comprises a first bearing body and a second bearing body able to rotate relative to each other. Each roller thrust bearing has a solenoid powered brake comprising two brake shoes each with a high friction brake pad mounted to a hinge body affixed to the first bearing body, a brake drum mounted to the second bearing body, a tension spring pushing the brake shoes against the brake drum, and a mechanism for disengaging the brake shoes from the brake drum. The mechanism comprises a slider body with space for two pins, two ball bearings, and a plunger with sloped surfaces on one end and a mounting provision on the other. A solenoid is attached to the mounting provision.

Abstract: What is presented is a mechanical arm assembly with a novel roller thrust bearing. The mechanical arm assembly comprises a first arm having a first end and a second end. A first roller thrust bearing is mounted to the first end and to a ceiling. A second roller thrust bearing mounted to the second end. Each roller thrust bearing comprises a first bearing body and a second bearing body able to rotate relative to each other. Each roller thrust bearing has a solenoid powered brake comprising two brake shoes each with a high friction brake pad mounted to a hinge body affixed to the first bearing body, a brake drum mounted to the second bearing body, a tension spring pushing the brake shoes against the brake drum, and a mechanism for disengaging the brake shoes from the brake drum. The mechanism comprises a slider body with space for two pins, two ball bearings, and a plunger with sloped surfaces on one end and a mounting provision on the other. A solenoid is attached to the mounting provision.