Patent ID: 7703473

Claim:
A valve exercising system comprising: a valve exerciser assembly for releasably engaging a stem of a valve and rotating the stem of the valve between an open condition and a closed condition; and a valve exerciser suspension arm assembly for supporting the valve exerciser assembly from a support, the suspension arm assembly maintaining the valve exerciser assembly in a uniform orientation as the suspension arm assembly is flexed, the suspension arm assembly comprising: a base element for mounting on the support; a first support element pivotally mounted on the base element; a second support element pivotally mounted on the first support element; a linking element pivotally mounted on the first support element; a first stabilizing element linking the base element and the linking element, the first stabilizing element being pivotally mounted to the base element and pivotally mounted to the linking element; a mounting element pivotally mounted on the second support element, the valve exerciser assembly being mounted on the mounting element; and a second stabilizing element linking the linking element and the mounting element, the second stabilizing element being pivotally mounted to the linking element and being pivotally mounted to the mounting element; at least two movement assistance assemblies for assisting pivot movement of the first support element with respect to the base element through an arc of movement, one of said assistance assemblies assisting pivot movement for a first portion of the arc of movement and said one assistance assembly not assisting pivot movement for a second portion of the arc of pivot movement.