Rubber ball-and-socket mount won't slip

June 1, 2000
Designing a product that is simple yet functional is something engineers strive for.

Designing a product that is simple yet functional is something engineers strive for. But the idea behind an innovative new universal ball-and-socket mounting system is so simple, it's almost hard to believe it is new. By replacing metal balls traditionally used in ball-and-socket designs with injection-molded rubber balls, National Products Inc., Seattle, created a lightweight, corrosion-resistant mount that won't slip. It is said to be the first ball and socket that has a no-slip feature.

Before getting to the trick behind the design, let's rewind to 1991 when inventor Jeffrey Carnevali, NPI president and CEO, was asked by a buddy to design a water-ski rack. Carnevali decided to use a ball and socket so that the rack would mount on any surface. However, after long hours spent at the drawing board, and in the foundry, trying to design a mounting system that holds tight, Carnevali concluded that using rigid, hard materials was futile.

"After all, a hardened ball and socket design is used for automobile suspensions, and even with close tolerances and tremendous loads, they always slip," he says. With this in mind, Carnevali decided to use a rubber ball instead. The RAM (Round-A-Mount) mounting system was born.

According to Carnevali, the main reason this system holds is because under pressure, a rubber ball doesn't compress but instead displaces and changes shape from a sphere to an irregular form. Any material that changes shape under pressure, yet is resilient enough to return to a sphere when pressure is released, can be used for the balls.

The RAM system consists of just eight components made from marine-grade, powder-coated aluminum along with stainless-steel hardware and rubber balls which come in four sizes. In the standard RAM system, a ball and socket rest at each end of a multipiece rod, allowing movement in any direction. Because it holds tremendous amounts of weight and withstands high vibration, RAM can be used in many military, aviation, marine, medical, photographic, music, electronic, automotive, and commercial applications.

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