John Deere introduced its 644K Hybrid wheel loader at the World of Concrete 2013. The machine runs on diesel-electric

LAS VEGAS—John Deere Forestry and Construction showcased its latest “bright ideas” at a Feb. 5 World of Concrete 2013 press conference: the 644K Hybrid wheel loader and the new E Series line of skid steers and compact track loaders. The manufacturer refers to the introduction of the new machine as a “bright idea” because it was developed using the culmination of show floor input, Deere’s “Chatterbox” customer feedback program and in-the-field comments.

The new loader uses two sources of energy — diesel and electric – capturing regenerated energy as it’s being created and uses it to power the machine.

The 644K Hybrid is equipped with a John Deere PowerTech 6.8-liter Interim Tier 4/Stage IIIB engine that runs at an operator-selected constant speed from 900 to 1,800 rpm. The hybrid has a net 229 horsepower and is equipped with all the key features of the conventional John Deere K-Series Wheel Loader line. (See the spec list at the bottom of this post for an at-a-glance look at the machines features.)

John Deere’s new 328E

The engine size is actually smaller than a conventional wheel loader in that it runs at a constant engine speed.  “It always has full power and creates electric energy,” John Chesterman, global product marketing manager for four-wheel drive loaders, John Deere Construction & Forestry, told editors at the press event. All the energy travels through three distinct orange cables. (For a video interview/walkaround of the 644K Hybrid with Chesterman, go to www.Facebook.com/BetterRoadsMagazine.)

The simplified transmission does not have a reverse gear. It’s not needed. The 644K Hybrid has four operating speed ranges, but no reverse gear or clutches as direction changes are performed by the electric motor.

Four main components pace the 644K’s electric-drive technology – the generator, inverter, motor and brake resistor.

Like conventional K-Series Loaders, a Sealed Switch Model (SSM) gives fingertip control of keyless start and 24 other machine functions. New to the SSM are engine speed adjust and coast control. The coast control feature allows the operator to enable dynamic braking through the SSM, reducing mechanical brake wear.

The machine’s generator is brushless and converts the rotational energy from the engine into three-phase alternating current (AC) electrical energy. It can also be driven as a motor to use recycled energy to drive hydraulics and save fuel.

The water-cooled inverter is a solid-state electronic system that delivers electrical energy to the motor.

The single electric motor is also brushless and converts three-phase (AC) back to rotational energy and torque. It replaces the job of a torque convertor, but can also work as a generator to recycle energy back into the system.

John Deere Forestry and Construction filled the bucket of the machines in one of its new E Series with light bulbs signifying the “bright ideas” used to develop this series and its new 644K Hybrid wheel loader

Because of the way the engine operations, the machine runs two decibels lower than the Interim Tier 4 model. A 3-decibel reduction is 50 percent quieter, which makes the lower level of noise significant.