The Sling Pump, with only one moving part, is a modern application of an Archimedes Snail Pump. A helical intake coil is wrapped around and around the inside surface of a cone. The coil is connected to an output tube via a water-lubricated swivel coupling at the extreme upstream side of the pump and is open at the downstream (fat) end. The downstream end of the cone has slats to let water in but keep debris out. A rope or pair of ropes holds it in place.
The pump floats partially submerged, being largely of plastic, with aluminum propeller blades and bouyant styrofoam in the nose. With each revolution of the cone, the coil picks up air during the top portion of the cycle and water during the bottom portion. This causes a pulsed output, and also means the output water is highly oxygenated. The Rife Hydraulic Engine Mfg. Co., Inc. claims some models of their Sling Pumps (inset) can raise water over 80 feet high or move it a mile horizonally, from a stream moving at just 1.5 feet per second. (Head doesn’t change with speed, only volume.) The unit weighs about 44 lbs. and uses a 1/2″ hose.
This pump is easy to construct, and can raise water to almost half the diameter of the wheel.
In its ancient form, a spiral channel is sandwiched between two circular plates, as shown on the right in a cutaway view where the front plate has been removed.
Another way to make a spiral pump is to use a piece of tubing in a spiral shape, attached to a single wheel.
Squeeze bulb pumps are often found on blood pressure cuffs.
In a blood pressure cuff air is pumped in first, before any measurements are taken. Then a needle valve is slightly opened and air is allowed to escape while the pressure is read from a sphygmomanometer (or sphygmometer).
Here, the air intake is on the right side of the drawing and the tube connects to the blood pressure cuff which is strapped to the patient’s arm.
In this squeeze bulb the valves are just rubber flapper valves like those used in many fish tank diaphragm air pumps. Other valve configurations are possible.
The STAR PUMP consists of a rotating star shaped gear inside of another gear. The inner gear has one less tooth than the outer gear.
The inner gear is usually the drive gear and pushes the outer, larger gear around. A tight fit where the gears mesh keeps fluid advancing around the pump.
In this drawing the dark kidney-shaped hole on the right is the intake and the one on the left is the outlet. As the teeth on the two gears separate the suction draws in the liquid.
This pump is best used for pumping lubricating fluids such as oil because the teeth must rub against each other somewhat. The amount of rubbing is slight but not insignificant.
Star pumps are also called GEROTOR PUMPS and the gears are called gerotor gears.
Sucker Rod Pump
The Sucker Rod Pump brings underground oil to the earth’s surface. It is driven by a motor which turns a flywheel with a crank arm.
Attached to the crank arm is a Pitman Arm which in turn, attaches to the Walking Beam. At the other end of the walking beam is the Horsehead.
The Hanger Cable hangs off the Horsehead, and is attached with a clamp to a Polished Rod, which goes through a Stuffing Box and is attached to the Rod String.
At the bottom of the well a Traveling Valve, often just a ball in a cage, is attached to the Plunger at the end of the Rod String. Below that is another ball in a cage, called a Standing Valve.
This pump can lift oil 10,000 feet or more!
Swash Plate Piston Pump
Swash plate pumps have a rotating cylinder containing pistons. A spring pushes the pistons against a stationary swash plate, which sits at an angle to the cylinder.
The pistons suck in fluid during half a revolution and push fluid out during the other half.
Shown on edge on the far right in the animation is a dark stationary disk. It contains two semi-circular ports. It is shown again in a head-on view below, right.
These ports allow the pistons to draw in fluid as they move toward the swash plate and discharge it as they move away.
For a given speed swash plate pumps can be of fixed displacement like this one, or variable by having a variable swash plate angle. The greater the slant the further the pistons move and the more fluid they transfer.
Note similarities to, and differences from, the wobble pump, radial piston pump, and bent axis pump.