Electronically controlled hydraulic systems have been around for years, but the technology is making dramatic improvements. Valve and control vendors are coming up with new techniques that give OEMs more capabilities, prompting a rapid upturn for the technology.
When John Deere unveiled its new 410H backhoe Wednesday morning, a spokesman credited Husco International of Waukesha, WI, for supplying “novel electrohydraulics.” The Intelligent Control Valve, dubbed Incova, has four independently-controlled electrohydraulic poppet valves for each function, giving the unit more capabilities than competitive systems. “We can do things other valves can’t do, like lower an arm using gravity to improve efficiency,” says Christopher Kolbe, marketing director at Husco.
The adoption of electronic controls is becoming more prevalent on engines, driven in par by the EPA’s Tier 3 regulation. The combination of digital controls and the networking that is often combined with these controllers creates a big opening for electrohydraulic systems. “Once electronic engines are in place, it’s easier to control proportional hydraulic valves,” says Kevin Huspen, distributor sales manager at HydraForce Inc. of Lincolnshire, IL.
More conventional electrohydraulic components offer benefits that OEMs want. “Electrohydraulic valves provide smoother operator control. They also make it possible to change the flow rate of a product by reprogramming it instead of designing a new valve when specs are changed,” says Doug Jahnke, marketing communications manager at Eaton Corp. of Eden Prairie, MN.
The growth of electrohydraulic technologies is evident at Sauer-Danfoss Inc. of Lincolnshire, IL. “We’re unveiling the first pump designed exclusively for electronic controls. That will provide better reliability because the parts normally used for mechanical controls have been removed,” says Dan Ricklefs, senior design engineer.
Bosch Rexroth Corp. of Wooster, OH, also unveiled a number of electrohydraulic modules including electronic control systems that can be used in open- or close-loop systems.
Eaton and other hydraulic manufacturers are moving to electrohydraulic systems.