Patent ID: 8660761
Filing Date: 2014-02-25
Classification: F16H,Y10T

Abstract:
1. A method of controlling a gear ratio change in a hydrostatic drive machine, wherein the hydrostatic drive machine includes a variable displacement pump and at least one variable displacement motor fluidly connected with the variable displacement pump, the method comprising steps of: determining a gear ratio rate of change corresponding to a change from a current gear ratio to a new gear ratio; determining start and stop overlap gear ratios corresponding to the gear ratio rate of change, wherein the start and stop overlap gear ratios define an overlap range; and changing from the current gear ratio to the new gear ratio using electronic signals at least in part by simultaneously changing displacements of the variable displacement pump and the at least one variable displacement motor at gear ratios within the overlap range, and sequentially changing displacements of the variable displacement pump and the at least one variable displacement motor at gear ratios outside the overlap range.