Rotary pumps are driven by a crankshaft that is rotated by handles on two flywheels attached to the ends of the shaft on each side of the pump. Rotary pumps can be built with two and three cylinders, and are operated by a team of two men. Pistons attached to the crankshaft draw in air through the inlet valves and then pump it through the outlet outlet valves to an air hose which delivers the air to the helmet of the diver. Cylinders, valves and outlet fittings for air are generally made from brass for corrosion resistance in the marine environment.
Lever pumps have two cylinders, which are operated by rocking a beam with handles attached to its ends which is pivoted at the centre. The piston rods are connected to the beam on either side of the pivot. Upward movement of the pistons pulls the air into the cylinders through the inlet valves, and then downward movement pumps the air through the hose to the helmet of the diver. Cylinders, valves and outlet for air are made from brass for the most reliability.
The pump may be mounted in a cabinet and may be fitted with a pressure gauge.
Historical Diving Society diving at Stoney Cove, England using two cylinder rotary pump
The crankshaft of three cylinder diving pump
|This naval article is a stub. You can help Wikipedia by expanding it.|
|This diving-related article is a stub. You can help Wikipedia by expanding it.|
|This technology-related article is a stub. You can help Wikipedia by expanding it.|