Patent ID: 11866912
Assignee: DOOSAN BOBCAT NORTH AMERICA, INC.
Field: Civil engineering (Other fields)
Classification: CPC E  F  B | IPC E  F

Claim 6:
7. A hydraulic drive system for use in a power machine, the hydraulic drive system comprising:
a hydraulic circuit that includes a hydraulic pump in hydraulic communication with a hydraulic drive motor, the hydraulic drive motor being configured to operate with infinitely variable displacement to drive the power machine; and
a control device that is configured to:
determine an output torque value associated with the hydraulic drive motor; and
selectively operate the hydraulic drive motor in either of a first displacement range or a second displacement range that overlaps with, but is different from, the first displacement range, the first displacement range having a first minimum displacement and a first maximum displacement and the second displacement range having a second minimum displacement and a second maximum displacement;
wherein operating the hydraulic drive motor within the first and second displacement ranges includes:
adjusting a run-time displacement of the hydraulic drive motor based upon the determined output torque value to run-time displacement values that are only within the first or second displacement range, respectively, including limiting a maximum run-time displacement based on the first or second maximum displacement, respectively, and limiting a minimum run-time displacement based on the first or second minimum displacement, respectively.