Patent ID: 8424824

Claim:
A balancer swivel arm assembly, comprising: a proximal bracket configured to be attached to a work station; a first intermediate link pivotably coupled to the proximal bracket with a first rotary shaft and a first plurality of radial bearings; a second intermediate link pivotably coupled to the first intermediate link with a second rotary shaft and a second plurality of radial bearings; a distal link pivotably coupled to the second intermediate link with a third rotary shaft and a third plurality of radial bearings; a slider bracket pivotably coupled to the distal link; a linear slider slidably mounted to the slider bracket; a tool attached to the linear slider; a spring balancer mounted to the slider bracket and coupled to the linear slider, wherein the spring balancer is at least partially enclosed in a vacuum evacuated cavity and is configured to support the linear slider and the tool through a linear range of motion along a first axis, wherein the first, second and third rotary shafts are aligned in parallel with the first axis, and wherein the first axis is perpendicular to a plane within which the swivel arm assembly is positioned.