Hydrostatic transmission mechanism

Abstract

Abstract A COMBINED MECHANICAL AND HYDROSTATIC TRANSMISSION HAVING THE SUN GEAR OF THE PLANETARY GEAR SET DRIVEN BY THE INPUT SHAFT THE CARRIER OF THE PLANETARY GEAR SET DRIVING THE OUTPUT SHAFT AND A PAIR OF HYDRAULIC UNITS, ONE OF WHICH HAS RELATIVELY ROTATING ELEMENTS, NAMELY, THE PLANETARY OF THE PLANETARY GEAR SET ELEMENTS, NAMELY, THE PLANETARY CARRIER AND THE RING GEAR, THE OTHER HYDRAULIC UNIT BEING IN FLUID COMMUNICATION WITH THE FIRST HYDRAULIC UNIT AND BEING CONNECTED BETWEEN THE FIXED ELEMENT OF THE CASE AND THE RING GEAR. BOTH HYDRAULIC UNITS HAVE VARIABLE DISPLACEMENT WHEREBY WITH ONE OF SAID HYDRAULIC UNITS BEING AT A GIVEN DISPLACEMENT, AND THE OTHER HYDRAULIC UNIT AT ZERO DISPLACEMENT THE RING GEAR OF THE PLANETARY GEAR SET WILL BE LOCKED AGAINST ROTATION WHEREBY THE FULL REDUCTION RATIO OF THE PLANETARY GEAR SET IS UTILIZED AND, IN THE SITUATION WHERE THE SAID ONE HYDRAULIC UNIT IS AT ZERO DISPLACEMENT, AND THE FIRST HYDRAULIC UNIT HAS A GIVEN DISPLACEMENT, THE FIRST HYDRAULIC UNIT WILL LOCK UP THE PLANETARY CARRIER AND THE RING GEAR TO PROVIDE A 1:1 DIRECT DRIVE. IN ADDITION, INFINITELY VARIABLE SPEED RATIOS ARE AVAILABLE BY HAVING THE PAIR OF HYDRAULIC UNITS IN VARIOUS DISPLACEMENT POSITIONS RELATIVE TO THE ABOVE LIMITS WHEREBY A FULL RANGE OF SPEED RATIOS IS AVAILABLE BETWEEN THE FULL REDUCTION RATIO OF THE PLANETARY GEAR SET AND A 1:1 DIRECT DRIVE.

Inventors

• 👤 Richard W Roberts

Bibliographic Details