When market conditions forced some California farmers to switch from electric motors to diesel engines to run the pumps that irrigate fields and orchards, they made an unwelcome discovery. Constant vibrations from the diesel engines were damaging their connected equipment.

As a solution, they turned to a coupling that helped dampen the vibrations, but the only style that fit their pumps was one designed for marine applications. It was a solution built for a different industry and priced too high for an agricultural operation.

Now, however, there is the LV-torsional coupling from Lovejoy Inc. of Downers Grove, Ill., which is designed and built to provide an economical alternative for not only the agricultural market, but for the off-highway construction equipment industry as well. Lovejoy makes two different styles: the LV-torsional coupling for U-joint drive systems and the LV-C for direct-drive systems.

Agricultural users would attach this kind of coupling to diesel engines driving deep wells and centrifugal pumps, while the construction industry would use this type of coupling on diesel engines that power portable compressors.

"The agricultural market doesn't have extra money to spend on equipment."

The LV-torsional coupling ranges in horsepower from 150 to 625 at 1,800 rpm, and comes in five sizes. The LV-C coupling has horsepower from 50 to 425 at 1,800 rpm in its six available sizes.

By providing relief from vibration, the torsional coupling helps to extend the life of machinery connected to the engine and pump, thus saving on expensive repairs and lost time during breakdowns.

One application where this coupling is already being used effectively is in almond groves in California. Almond growers use pumps to flood the groves at night, enabling water to seep into the ground. Grape cultivators, and other fruit and vegetable growers use similar irrigation methods and, therefore, a lot of diesel-drive pumps.

In the construction industry, the most common application for the LV-torsional coupling would be portable compressors on-site that power jackhammers or other equipment.

According to Jim Mahan, director of engineering at Lovejoy who helped to create these new couplings, "The agricultural market doesn't have a lot of extra money to spend on additional equipment. And the construction industry is highly competitive. Both require parts with a long lifespan," he said.

Perforated paper on a roll is meant to tear. That's why it's perfed in the first place. So think of the control you need over machines that roll it up.

ABB has told us about one of the jobs its New Zealand contingent handled that helped make the process more efficient for a local paper company.

For those of us in the north, New Zealand is "down under." Although the Coriolis force goes the other way and people see some different constellations in the sky, we're pretty sure that all the natural laws are still in effect. If you give a strip of paper a good yank, for example, it's likely to tear.

So the machinery that takes a large roll of soft paper through the steps of embossing, printing, perfuming, and perforation at fixed intervals must be carefully controlled if it's going to be useful.

ABB's customer had controlled rewinders—which move paper from the big roles, through the process, and onto smaller rolls—with a mechanical cam system. It worked well, but required downtime to change the cams whenever production switched from one product to another. The paper company wanted a more efficient arrangement.

A New Zealand paper maker replaced mechanical cams with PLCs and individual electric drives.

Gayomurd Desai, a senior automation engineer for ABB Automation Technologies, New Zealand, worked with one of the customer company's engineers to replace the cams with electronics and the driveshaft with individual drives.

The final system made use of ABB's ACS600/800 direct torque control drives in combination with programmable logic controllers. ABB said it kept the system economical by using the Profibus fieldbus network for communications between drives and controls. The company said its Pressductor load cells help maintain accurate tension on the fragile rolls of paper towels and toilet tissue.

The change, ABB said, increased line speed from 750 meters a minute to 1,000. The company also pointed out that there are no longer cams needing to be changed by hand or needing maintenance. ABB added that the customer has standardized the rewinders at all its plants in New Zealand with the new system.

An industrial-strength, steel-belted tooth drive is playing a key role in a new product from Remstar International Inc. of Westbrook, Maine.

The Shuttle XP vertical lift module uses that belt drive to realize higher speeds and greater durability. The belt drive's design allows multiple contact points to provide increased weight, safety, and total load capacity.

A new design allows for multiple points of contact for increased safety and load capacity.

With no metal-on-metal moving parts or friction, steel-belted tooth belts don't need lubrication, aren't prone to stretching or metal wear, and require less maintenance. The design is meant to increase a system's strength and speed for cleaner and faster operation.

The technology reduces ambient unit sound, unlike chains, rack and pinion, or wires, since it makes use of the same concept used in vehicle tires.

Overhead storage space is maximized and floor space increased, because the Shuttle XP VLM can handle loads up to 132,000 pounds, and reach 65 feet high.

A recreational vehicle promises the comforts of one's own bed no matter where you are. But some RV-ers have found themselves more at sea than at home: Because of give in the trailer's suspension and jacks, the "fifth wheel" can sway back and forth or side to side as occupants move around.

"It's really noticeable at night," said Jim Thorpe, president of JT's RV Accessories in Paso Robles, Calif. "Say a man gets up in the middle of the night; his wife, who's still in bed, will feel the whole RV rock."

Thorpe has spent many a night in an RV. At one time, he managed a dirt track racing team and traveled to 130 races a year. Even after he retired, he still spent his vacations on the road. One Thanksgiving, when his RV-driving friends complained about stability problems with their parked trailers, Thorpe, who had gone into light manufacturing after his racing career, decided he could come up with a solution. Within a few weeks, he had outfitted his RV with stabilizing bars.

The bars, now manufactured by Thorpe under the name Strong Arm Jack Stabilizer, attach to the underside of the RV and to the jacks that support the front of the trailer when it's parked. The bars telescope out when the jacks are lowered, and then they are locked into place to form a set of rigid triangles.

"With the triangles locked into place, the legs can't flex anymore," Thorpe said.

As an added bonus, Thorpe said, the leg stabilizers make setting up the trailer faster and easier. When he was on the road with his racing team, it might have taken 20 minutes or more to get his RV leveled. Now, he said, it takes just a few minutes to lock everything into place.

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© 2005 by The American Society of Mechanical Engineers