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Skid Steer Loader

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Equipment Specifications - RitchieSpecs
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2005 John Deere 325 Skid Steer Loader
The skid steer loader is known for its compact size and versatility. It is a four-wheel drive loader with double acting cylinders allowing the left and right wheels to act independently of each other. The name "skid steer" comes from the vehicles wheels' ability to drive in opposite directions, making it skid. The bucket of the skid steer can be replaced by a variety of other attachments like a hydraulic breaker, pallet forks, angle broom, sweeper, auger, mower, snow blower, stump grinder, tree spade, trencher, dumping hopper, ripper, tillers, grapple, tilt, roller, snow blade, wheel saw, cement mixer, and wood chipper.

The skid steer is also available as a tracked machine, known as a multi terrain loader.

Contents

[edit] History

[edit] From Turkey Manure to the State Fair

The skid steer loader was invented to clean up turkey manure. In the mid-1950s, a Minnesota turkey farm owner, Eddie Velo, constructed a two-story barn to house his growing flock of birds. Tractor loaders of the time were much too big and heavy to maneuver throughout the barn to clean it so Velo asked a local repair and fabrication company for help.

Keller Manufacturing was a small Minnesota business owned by brothers Louis and Cyril Keller. Their previous experience with manufacturing was with snow blowers. However, in the summer of 1956, the brothers welcomed Eddie Velo's request to develop a vehicle to help him clean his barns. They began by designing an initial drive system with plenty of maneuverability and, realizing the marketability of what they had created, approached Velo with a plan. Velo agreed to fund the production of the vehicle with the assumption that if the vehicle did not work he would not be liable to pay for their labor.

By February 4, 1957, a prototype was created and prepared for testing. It was a front-loading, three-wheeled vehicle with a rear caster wheel, able to turn around its own length. The new loader was tested in Velo's barn allowing the Kellers to make specific adjustments as needed. The only major problem was the belt drive's tendency to slip off a pulley disabling the entire machine. As a result, the Kellers designed and patented a new clutch system that eliminated the belt problem.

Soon, the Kellers decided to put their new improved loader into production. By fall of 1958 they had manufactured six new loaders, powered by 6.6 horsepower Kohler Engines. Meanwhile, they were seeking funding for mass production. Eventually they received $250,000 from a bank in their hometown of Rothsay, Minnesota while a North Dakota company, Melroe Manufacturing Co., supplied the rest of the necessary financial support.

One of the six new 1958 loaders was showcased in the Melroe booth at Minnesota State Fair and received much acclaim. Melroe was rewarded with sole manufacturing rights on a royalty basis. Both Keller's were then hired by Melroe to continue the loader's development.[1]

2005 Bobcat S250 Skid Steer Loader

[edit] From Melroe to Bobcat

In just a short time the Keller's had developed their first Melroe loader, introducing it in early 1959. The new loader did not stray too far from the previous Keller models except that the new manufacturing facilities allowed the vehicle to be larger and more professional looking. It was powered by a nine horsepower, model AENL, Wisconsin engine and featured a rear frame fabricated from steel plates. After successful tests of the new model they manufactured five more.

At this point Cyril Keller became the loader's traveling salesman while his brother Louis remained in North Dakota developing improvements. The first model established for production was the M60 Self-Propelled Loader, followed immediately by the M60 Improved. Its features included a cast rear frame, a 12.9 horsepower, two-cylinder ONAN engine, and a "Grasshopper boom" for the bucket. It was called a "Grasshopper boom" because it resembled the angled legs of a grasshopper.

Keller improved the M60 by straightening the boom, making it easier for fabrication. The new model was called the M200.

The third Melroe loader was the M400. It was the first four-wheel drive skid steer model. The model was developed as a result of the dwindling poultry market, requiring the loader to find new customers. The fourth wheel allowed the vehicle to work in varying conditions. The two separate axles maintained the vehicles maneuverability. Sales increased with the release of the M400. Melroe also sold a kit to convert the M200s and M60s into four-wheeled models.

However, new markets presented new problems. The fertilizer market experienced corrosion in the exposed drive system. Debris was causing the chains to jump off the sprockets. The new markets also needed a stronger bucket and boom. So, the Kellers installed a two-cylinder system into the lift arms.

The first model to have both an enclosed drive shaft and double acting cylinders was the M440 Melroe Bobcat, in 1962. It also had 70/30 back to front weight distribution to enable ease in steering[2]

[edit] From Bobcat to the Open Market

The name Bobcat was chosen by Lynn Bickett. A mammal defined as "tough, quick and agile," he believed it perfectly represented the new M440 Melroe skid steer loader.

Melroe Manufacturing followed up the Bobcat with the M444, which introduced pressurized oil to the clutch system, and the M500, that had a 24hp Kohler engine. The next two models simply increased engine power again. The M600 had a four-cylinder 25 horsepower Wisconsin Engine, and the M610 had a four-cylinder, 30 horsepower Wisconsin Engine.

Many more models followed in Bobcat production. Also, as other manufacturers recognized the versatility of the skid steer loader, they added them to their production lines. John Deere, JLG, JCB, Case New Holland (CNH Global), Gehl, Mustang, ASV, Caterpillar and many more have produced skid steer loaders.

Competition increased advancements, most notably the introduction of hydrostatic drive models and crawler tracks. The crawler-tracked model is known as an multi terrain loader.[3]

[edit] Features/How it Works

The introduction of hydrostatic motors resulted in the disappearance of the transmission. Instead, a set of pumps and hydraulic motors power the vehicle. Each vehicle has four pumps and two motors, one for each set of wheels. The motors operate in a unique way to ensure that the vehicle does not stall. While operating the wheels the full force of the motor focuses on this function, and when using the other implements its power focus changes. Also, to maintain maneuverability, each motor powers a separate set of wheels, enabling each side to drive in different directions and turn on a dime.

Each of the motors connects to a sprocket, and two chains connect each wheel to the sprockets. All the chains and sprockets are in a sealed compartment within the frame and are immersed in an oil bath to maintain their lubrication.

The loader arms are also operated with hydraulics allowing the bucket (or another of the many tool attachments available) to lift in either a radial or vertical movement. Unlike many other loaders, the lift arms run along either side of the cab and hinge near the rear of the vehicle. A radial movement has the bucket move in an arc away from the vehicle until it reaches the height of the cab and then moves back inward. The vertical movement is similar to the radial until it reaches the operators eye-level and then lifts directly upwards instead of inwards. When not in use, the arms are fully lowered to provide increased stability.

The engine is located in the rear of the machine in an easily accessible compartment, allowing for quick and easy repairs.[4]

[edit] Common Manufacturers

[edit] Additional Photos

See Skid Steer Loader (Photo Gallery)

[edit] Used & Unused Skid Steers for Sale

Search for unused and used skid steers being sold at Ritchie Bros. unreserved public auctions.

[edit] References

  1. Skid Steer. Howstuffworks.com 2008-09-24.
  2. Skid Steer Loaders. Skid Steer History. 2008-09-24.
  3. Skid Steer Loader. Agricultural Equipment. 2008-09-24.
  4. Skid Steer Loader. Skid Steer Sale. 2008-09-24.