The xed points and hyper-order of solutions of second order linear di er-ential equations

A hydromechanical transmission in which the first and second drive ranges are input-split drives. In one embodiment the transmission includes a hydrostatic portion comprised of two hydraulically interconnected, variable displacement, hydraulic pump-motor units and two planetary gear sets which are controlled by a brake and a clutch to provide the two ranges. In another embodiment a third planetary gear set and a second clutch are added to provide increased torque coverage in first range and also provide a third drive range. In both embodiments the speed ratio within the drive ranges is varied by controlling the displacement ratio between the pump-motor units. The shifting from one drive range to another occurs at synchronous speeds, thereby reducing the shift energy absorption required in the clutches and brakes.