Patent ID: 7575538

Claim:
An apparatus comprising: a guide assembly able to slide along a guide path, having an axis of translation parallel to said guide path, and having a first guide end and a second guide end; an arm assembly pivotally coupled to said guide assembly, having an axis of rotation perpendicular to said axis of translation, and comprising a first arm including a distal end and a pivot end pivotally coupled to the first guide end at the axis of rotation, a second arm including a distal end and a pivot end pivotally coupled to the second guide end at the axis of rotation, a first pulley assembly comprising a first rotating structure rotationally attached to the distal end of the first arm and that contains at least one pulley, and a second pulley assembly comprising a second rotating structure rotationally attached to the distal end of the second arm and that contains at least one pulley; a resistance assembly comprising a source of force and a selective means of engaging a portion of said source of force; and a cable assembly means for transferring force and allowing rotation and translation, comprising a first cable end positioned adjacent to the first pulley assembly and a second cable end positioned adjacent to the second pulley assembly, such that the first cable end and the second cable end are in communication with the resistance assembly and remain substantially at the same location adjacent the pulley assemblies during rotation of the first and second arms and translation of the guide assembly without substantially engaging the resistance assembly and without the need to perform any secondary operations.