Shock absorbers that help electric light bulbs last longer

Replacing a burned-out light bulb can be a time-consuming nuisance, require some fancy footwork on a ladder, and besides, cost money. So at a time when people are becoming more and more energy-alert, what can be done to cut down the frequency of changing a light bulb? It's a simple enough request.

Of course, you can reduce the number of times you snap on a light fixture. But that may be inconvenient at best.

You can go back to candles or whale-oil lamps; or you can light a fire in the fire- place and read by the reflected glow of the flames.

Ira Wolf, president of American Electro-Dynamics Corporation, has a different idea. If he were building cars, he might call it a better idea.

In any event, Mr. Wolf has taken an idea which went all the way to the moon and now is using it to help earthlings save money on light bulbs.

Indeed, his product, the Bulb-Miser, which has been around for two or three years and was sold by another company which Mr. Wolf's firm brought out, is a thermal shock-absorbing disc. When put into a light socket before the bulb, it enables an incandescent bulb to slowlym light up, and in so doing the life expectancy of the bulb is stretched many times.

It's the initial jolt of power that weakens and eventually destroys the filament in a light bulb, explains Mr. Wolf. In other words, few light bulbs fail while on.

"Most bulbs fail when they are first turned on," he adds. "The filament has to carry up to 20 times its rated current and heats up to 4,000 degrees F. in about one- tenth of a second." That's when a weaker bulb pops.

The Bulb-Miser causes an incandescent light bulb to reach maximum output in a few seconds compared to the instant response without it.

The device is about the size of a US quarter, looks like a washer, and relies on thermister technology to do the job. Cost is $2.98. How long it takes to achieve a saving depends, of course, on the price you pay for a light bulb and how often it is switched on and off.

It is particularly useful in commercial and industrial installations where thousands of light bulbs are changed each year. Too, the location of the bulbs has a bearing on the subject as well. If a light fixture is situated in a high or awkward spot, then it is always advantageous to reduce the frequency of bulb change.

Hotels and theaters, for example, often replace all of their bulbs every few months. As a result, says Mr. Wolf, companies such as Howard Johnson, General Mills, IBM, US Steel, Lockheed, and Hilton Hotels have reached for his product in the last couple years.

It also makes sense when decorative, high-cost bulbs are used in an installation.

The device cannot be used in a light socket which takes a 3-way bulb without an adapter, however. A 3-way bulb has two filaments. The adapter costs money and extends the length of the payback.

In 1980 American Electro-Dynamics sold about 1.2 million of the little disks. Sales in 1981 could be up sharply. Gulf Oil Company not long ago offered it to 25,000 of its credit-card holders out of a total of 1.7 million. Gulf expected a return of 1 percent and got 4 percent. Texaco and Arco also are planning test mailings to their card holders as well.

The Bulb-Miser technology was developed during the National Aeronautics and Space Administration's Apollo program to protect the Saturn launch vehicle from electrical current surge .

It now has come back to earth.