Patent ID: 9109680
Filing Date: 2015-08-18
Classification: F16H

Abstract:
1. A hydrostatic mechanical power split transmission, comprising: a drive engine; a housing; a first power branch comprised of a hydraulic pump, a hydraulic motor, a first drive shaft, and a first plurality of clutches; a planetary gear system comprising a sun gear and a ring gear; and a second power branch driven either one of directly or indirectly by the drive engine and comprising a second drive shaft, a second clutch, and a plurality of gear wheels; wherein the first drive shaft is selectively coupled or decoupled, either directly or indirectly, to either one of said sun gear or said ring gear by at least one of said first plurality of clutches; wherein the planetary gear system has a gear ratio in relation to the first drive shaft for optimizing performance of the first power branch; wherein the plurality of gear wheels of the second power branch provides a gear ratio for optimizing performance of the second power branch; wherein the second clutch couples the second drive shaft to the sun gear of the planetary gear system; and wherein the planetary gear system is switchable to a state of constrained motion by concurrent engagement with each one of said plurality of first clutches of said first power branch so as to reduce mechanical friction and oil churning losses.