Spring biased support for electrotherapeutic apparatus articulated arm structure

Claim 1

In electrotherapeutic apparatus including a cabinet containing electrical power means, a therapeutic treatment head spaced from the cabinet to be bodily maneuvered relative thereto and in relation to a patient, and an electrical connector extending between said power means and head to communicate power to the head, the improvement comprising a. articulated arm structure supported by the cabinet and supporting the head, said structure including first and second cup-shaped joint members interconnected to define a generally horizontal axis of member relative rotation characterized in that a first mode oF arm structure articulation is achieved in response to rotation of the second member relative to the first member about said axis to lower said head, said second member transmitting weight of the head to said first member, b. first torsion spring means extending interiorly of said members and operatively connected thereto to yieldably resist said arm structure articulation in said first mode while blocking downward collapse of arm structure between said members and head when projecting generally horizontally and when said cup-shaped members are otherwise freely relatively rotatable about said horizontal axis, and c. said members having spaced inner walls facing axially oppositely and there being integral lugs on the members projecting generally horizontally into such space and away from said opposite walls, said torsion spring means including multiple coil windings extending about said axis and having torsion transmitting projections extending generally away from said axis at opposite ends of the windings and into operative engagement with the respective lugs, the members extending in such axially confining relation to said spring means as to block axial displacement of the projections from the respective lugs.