A Useful Tyre-inflation Regulator.
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When Using a tyre pump of the power-operated pattern it is usually necessary to stop the pump and remove the tyre connection several times in order to test the pressure with an independent gauge. This is a slip-shod method, but it is really necessary% without a special fitting, owing to the fact that the restricted passage in the tyre valve absorbs some of the pressure, so that the gauge shows a higher figure than that actually attained in the tyre.
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To avoid this trouble, Research Engineers, Ltd., Chalk Farm, London, N.W.1, has devised a neat inflation regulator which consists of a reliable pressure gauge and a special cock. It has suitable nozzles for fitting into the pipe line in any convenient position. The cock has three positions : (1) for tyre inflation, (2) for measuring the pressure and (3) for reducing the pressure. When in the fleet position, the pressure gauge shows the pressure in
the tyre plus that required to force the air throegh the valve, but in the second position the exact tyre pressure is indicated as the air from the pump escapes through a by-pass.
The regulator can be supplied with any of the three different gauges reading to 50 lb., 100 lb. and 200 lb. per sq. in. The price, with 2 ft. of hose and tyre connector, is £2 13s. 4d. The device is marketed in two different types.