Loading balancer assembly

Claim 1

A HOISTING BALANCER ASSEMBLY COMPRISING A HANGER HAVING A BASE MEMBER AND A PAIR OF SPACED GENERALLY VERTICAL ARM CONNECTED THERETO; A GENERALLY HORIZONTAL FIRST ARM PIVOTALLY MOUNTED BETWEEN SAID ARMS FOR ROTATION ABOUT A HORIZONTAL AXIS; A GENERALLY VERTICAL SECOND ARM ADAPTED TO RECEIVE A LOAD TO BE HOISTED AND BALANCED BY SAID ASSEMBLY, SAID SECOND ARM BEING PIVOTALLY CONNECTED TO ONE END OF SIAD FIRST ARM; A THIRD ARM PIVOTALLY CONNECTED TO SAID SECOND ARM; AND A FOURTH ARM PIVOTALLY CONNECTED AT ONE END TO THE OTHER END OF SAID FIRST ARM AND AT ITS OTHER END TO SAID THIRD ARM, SAID ARMS BETWEEN SAID PIVOTAL CONNECTIONS FORMING A PARALLELOGRAM; A COUNTERWEIGHT OPERATIVELY CONNECTED TO ONE OF SAID ARMS; AND MEANS FOR APPLYING A GENERALLY VERTICAL FORCE TO SAID THIRD ARM, SAID MEANS COMPRISING A FLUID-ACTUATED PISTON, A CYLINDER IN WHICH SAID PISTON IS RECIPROCABLE, SDAID CYLINDER BEING ATTACHED TO SAID HANGER BY MEANS WHICH PERMITS SAID PISTON TO EXERT A FORCE IN A VERTICAL DIRECTION REGARDLESS OF THE POSITION OF SAID FIRST ARM, THE UPPER END OF SAID CYLINDER BEING FREE TO MOVE HORIZONTALLY AS REQUIRED TO MAINTAIN THE CYLINDER WITH ITS AXIS IN A VERTICAL POSITION.