Clark Equipment Compnay

Doosan Bobcat North America Inc.

Douglas Kallas

Charles Young

Matthew Kaldor

Scott W Becker

Marty Carpenter

Eric Zabel

Boston Zachmann

Sloan Balo

Scott Becker

A hydraulic work system can include a continuously variable displacement hydraulic pump that is powered by an engine and is in communication with a hydraulic actuator. A run-time displacement of the hydraulic pump for movement of the hydraulic actuator can be controlled based on a speed of the engine.

System and methods for cycle time management

A power machine can include a hydraulic drive system that includes an infinitely variable hydraulic drive motor. A run-time displacement of the hydraulic motor can be adjusted based on commanded travel speed or based on a output torque. In some case, the run-time displacement can be selected from one of a plurality of displacement ranges, such as a high range and a low range.

Drive motor displacement control

A control system is provided for a power machine that includes a hydraulic charge circuit with a hydraulic charge pump, and a variable displacement drive pump. A signal for control of displacement of the drive pump can be diverted from the hydraulic charge circuit downstream from the pump, including via a flow path that branches from the hydraulic charge circuit from a location upstream of a hydraulic load.

Externally regulated control for drive pump

A control system for a hydrostatic drive system can include a hydraulic charge pump circuit having a hydraulic load and a tank. The hydraulic charge pump can be in fluid communication with the hydraulic charge pump circuit. A bypass line can extend to the tank from a junction between the hydraulic charge pump and the hydraulic load. A charge bypass valve can be disposed to control flow through the bypass line. The control system can include a control device configured to determine one or more operational parameters for the power machine and control the charge bypass valve to allow flow through the bypass line, from the hydraulic charge pump to the tank, based on the determined operational parameters during a starting operation.

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Mandan, ND, United States of America

Douglas Kallas