Traction control lifts genie in rough terrain

Enhancing one of its most popular lift models, Genie Industries has introduced a new traction control drive system on its GS-68 RT series of rough terrain scissor lifts. Available on both the GS-2668 RT and GS-3268 RT lifts, two of six models Genie offers in its rough terrain series, the new drive system provides enhanced traction, giving the scissor lifts additional capability in wet and uneven terrain.

"Our customers, especially those in the Northeast, face some pretty severe conditions," said John Norton, Genie product manager. "Depending on the season, they can be up to their ankles in mud, knee deep in snow or covered with ice."

Now with the traction control drive, Norton said, "we took a really good machine and made it a great machine. It has greater utilization and can get to more areas in rough terrain environments."

Designed for both indoor and outdoor applications, the GS-2668 RT and GS-3268 RT scissor lifts are available with diesel, gasoline or propane power options, all of which are located on a swing-out engine tray for easier service access. The diesel power option is either a 0.90 L three-cylinder Kubota D905 engine rated 20 hp or a 1.13 L three-cylinder Perkins 403C-11 engine rated 26 hp. The Kubota engine is prepackaged with a Donaldson air cleaner and a Denso radiator, while the Perkins diesel is equipped with those components at Genie's Redmond, Wash., manufacturing facility. Genie's other rough terrain scissor lifts (the GS-3384 RT, GS-3390 RT, GS-4390 RT and GS-5390 RT) feature a similar traction drive that uses a closed-loop figuration. Beefing up the traction control drive system on the GS-2668 RT and GS-3268 RT required adding a HydraForce combiner/divider valve to the circuit, which directs flow from the Bosch Rexroth two-section hydraulic pump (0.488 cu.in, displacement per section) to White Drive Products motors mounted at the wheels. It is the combiner/divider valve that ensures flow reaches each wheel independently, allowing maximum ground power even during loss of contact. When a wheel loses contact with the ground, the traction drive is designed to maintain 75% power.

Displacement in each of the wheel motors was also increased from 28.3 cu.in, to 32.7 cu.in., which Norton said improves gradability, giving the lifts access to 35 to 40% grades. It is also designed to reduce the average drive pressure, which minimizes wear and tear.

Other features of the drive system include two drive modes: a parallel mode which assists in uphill travel using a slower speed with maximum torque; and a series mode which is ideal for operation on flat, level ground, operating at a higher travel speed with less torque. Both machines are four-wheel drive, have dynamic braking, a spring-applied hydraulic release parking brake and foam-filled tires. Inside turning radius on the machines is 5 ft.

The drive system hydraulics on the GS-2668 RT and GS-3268 RT models also power the work platform. The two-section Bosch Rexroth pump supplies flow to Dongyang hydraulic lift cylinders to raise and lower the 66 sq.ft, platform, operated by an electronically controlled Hall effect joystick which Norton said provides "smoother control, particularly on rough terrain." Lift capacity on the work platform is 1000 to 1250 lb.

The GS-2668 RT and GS-3268 RT lifts are available with a series of options such as automatic leveling hydraulic outriggers, a 2 kW generator to power hand tools, cold-start package and a series of light systems. A hot weather kit is standard on the machines. Weights on the GS-2668 RT and GS-3268 RT are 6373 and 8008 lb.

Genie began offering the new traction control drive system on the GS-2668 RT and GS-3268 RT scissor lifts last fall. Both machines are manufactured at its Redmond, Wash., headquarter facilities.