There are times when even rubber tracks can’t keep grain carts afloat and moving.
Those are the times when farmers wish they could pump some of their tractor’s excess horsepower back to the cart for an extra push.
It’s what Elmer’s Manufacturing is promising with its hydrostatic drive Power Tracks, which can be installed under their air carts, tender carts and grain carts.
Engineers at Elmer’s in Winkler, Man., and Horsch in Germany have been working on power driven tracks for awhile.
In one case, a prototype Power Track near Estevan, Sask., pulled a 1,000 bushel cart, an 80-foot drill and a JD 9560R backward out of the quagmire in which they had become immersed.
Since then, engineers from Elmer’s and Horsch have worked to refine the system and get it ready for production, which should begin soon, said Mike Friesen, president and chief engineer at Elmer’s.
He said Power Tracks will be available in time for next spring.
“The system transfers 250 excess horsepower from the tractor back to the hydrostatically driven rubber tracks,” Friesen said.
“What it amounts to is taking horsepower you can’t use from the tractor and applying it to another drive system. You’re re-distributing tractive power, same as adding more dual tires or more rubber tracks, but they’re on the cart.”
Friesen said Power Track is designed only for those urgent situations when wheel slip is an issue. It is not designed for use in normal field conditions.
Once the system has extricated the rig from the mud, the operator switches Power Track back into the non-driven mode. As well, it automatically defaults into non-drive mode when ground speed exceeds eight m.p.h. The hydraulic system ensures that activation and de-activation is smooth.
Friesen said Power Track can use up to 117 gallons per minute at 6,000 p.s.i., sending the 250 h.p. back to four radial piston hydraulic wheel assist motors positioned within the rear wheels of the tracks.
“It’s all about pressure. It’s just like more voltage in an electrical motor. With 117 g.p.m. at 6,000 (pounds per sq. inch), we have an enormous amount of pulling power in the tracks.”
Tractors don’t generate that much hydraulic power, so the engineers installed a power take-off driven Saur Danfoss axial piston pump, which is the same unit used on many combines and sprayers. The electronically regulated pump is driven through a three-way gearbox so an auger can be used with the power tracks.
Each rubber track is supported by two large drive wheels at the rear, two large non-driven wheels at the front and eight bogie wheels. A pair of tracks has four driven wheels at the rear, each with its own integrated radial piston motor.
Controlling the mighty mass of tractive power is the job of the electronics package. The primary controls are simply on or off and forward or backward because the system is used only when the rig is stuck. Electronic components include a wheel speed indicator, an RPM indicator, a solenoid to activate the optional auger, a forward/neutral/reverse switch, a temperature sensor and a pressure gauge.
It may seem like the cart is pushing the horse when the system is activated in the forward mode, To prevent this from happening, and to help the operator maintain control, the system automatically matches cart ground speed to the tractor’s radar speed.
The system’s few controls and gauges fit into a compact console in the cab. The operator controls the amount of power applied to the tracks with a knob. If he feels the bottom sinking away, he hits the boost button and 100 percent power instantly flows to the tracks.
Using the system involves:
- engaging the p.t.o.
- switching from freewheel to either forward or reverse
- using the knob to increase or decrease power to the tracks
- hitting the boost button
For more information, contact Friesen at 204-324-6263 or visit www.elmersmfg.com.