Electro-hydraulic, servo-piston control: Hydrostatic pump family expands
. has released the H1 45/53cc and 78cc single pumps, joining its 147/165cc single pump and the 45/53cc integral tandem pump. H1 is geared to enhance electro-hydraulic performance and to complement overall machine operating performance for a variety of propel and non-propel applications. The H1 family of compact closed-circuit variable displacement axial piston pumps features high power density. Units use an integral electro-hydraulic servo piston assembly that controls rate and direction of hydraulic flow.
The new hydrostatic pumps offer the OEM “better horsepower management via improved total pump efficiency, in addition to helping control vehicle maintenance and operating costs,” according to Randy Rodgers, product portfolio manager. “Optimizing around electronic control is the future of mobile machinery because tomorrow’s electronically controlled engines are going to need electronically controlled pumps. H1 is fully Plus+1 Compliant to interface seamlessly with Sauer-Danfoss’ electronic machine control architecture.” he says
Among their operating characteristics, H1 pumps reduce rotating group, control and charge pump losses, which saves fuel consumption, frees power for other vehicle functions, and enhances operating performance and productivity. “Better efficiency means you can use smaller engines on some machines,” says Rodgers, “while you reduce machine heat load and increase power to the ground. The market is expecting machines with enhanced operator and/or vehicle safety features. We built more functionality into H1, particularly with respect to addressing elements surrounding safe vehicle operation.”
Options that are designed to improve operator and vehicle safety include a tandem control cut off (CCO) circuit to safely disable both pump controls in the absence of the proper signal to the override solenoid, an integral speed limitation (ISL) circuit that improves vehicle braking while preventing engine over-speed, and integral pressure filtration with a filter bypass sensor and switch to prompt filter service and maintenance. Pumps have at least one “clean side,” facilitating machine design and installation, the company says.