Skid-steer loaders have become commonplace at construction sites around the world. And it’s no wonder; they offer a high return on investment because the wide variety of attachments available for them enables a single machine to do the work of many different ones.
But don’t throw in the towel on loader- backhoes, which continue to be the real workhorses of industry after well more than 30 years. They can quickly be converted from backhoe to loader (and vice versa), and an increasingly wide variety of tools has added to the versatility of these machines. Not only that, but they are easy to control and extremely efficient at digging —even in cramped quarters.
Among the newest members of the loader-backhoe market is the fourwheel- drive TLB-6235 from Allmand Bros. Inc., Holdrege, Neb. The TLB- 6235 starts with a 35-hp Isuzu diesel engine driving an Eaton variable-displacement, axial-piston pump capable of delivering 38.9 gpm of hydraulic flow at 3000 rpm. Sized at 3.0 in.3/rev (49.2 cc/rev), the pump can maintain continuous pressure at 3000 psi and intermittent pressure to 5000 psi.
This hydraulic power, coupled with an additional 8 gpm of hydraulic power from a tandem mounted gear pump for auxiliary functions, drives the propulsion system, brakes, steering, and implement functions of the TLB-6235. Fluid from axial- piston pump flows to a pair of Eaton axial-piston motors sized at 3 cc/rev. Each motor is connected to a planetary gear, limited-slip differential that drives a pair of wheels at ground speeds to 7.5 mph. The gearing not only increases torque from the motors, but allows the motors to run at a speed that produces smooth motion and high efficiency.
