SPEED-O-MATIC

VARIABLE PRESSURE HYDRAULIC SYSTEMS FOR CONTROLLING THE OPERATING FUNCTIONS OF MACHINES,SUCH AS CRANES, SHOVELS, DRAGLINES, OR THE LIKE, EACH SYSTEM INCLUDING SUCH ELEMENTS AS A SOURCE OF SUPPLY OF FLUID, A PUMP, AN ACCUMULATOR, A PLURALITY OF FLUID MOTORS, A PIPING SYSTEM, AND FLUID FLOW CONTROLLING VALVES