Bicycle pump

An air pump is a device for filling a closed container with air, while the internal pressure of the container increases. The air pump was invented in 1649 by Otto von Guericke.

The hand air pump, for example, for filling bicycle tires, is a piston pump. It consists of a cylinder and a piston movable therein, which is moved by a rod to a handle. However, the piston does not seal only during compression and insertion into the container against the cylindrical wall off during the return stroke, so that a new charge can pass into the cylinder from the outside while the reverse flow is prevented from the container into the pump cylinder through a valve, which either on the container ( bicycle inner tube ) or at the lower end of the pump cylinder ( air pump for balls ) is located. The problem is a high pumping frequency. In case of bad material, the piston may break.

A mechanically operated air pump is called a compressor or compressor.

History

Otto von Guericke invented in 1649 the piston vacuum pump, which was referred to in the encyclopedias of the 19th century as an air pump. John Boyd Dunlop developed in 1888 the first bicycle tire and pumped it on with a football pump.

Bicycle pump

A bicycle pump is particularly adapted for filling bike tires with air. Fundamentally can be distinguished in hand, foot and floor pumps. With hand pumps can be tire to approximately 5 bar pressure pump up, good floor pumps reach more than 12 bar, the tire pressure of a bicycle is significantly higher than that of a car tire.

Not every pump is suitable for all bicycle valves. This can by screwing adapters or universal pumps that have different valve heads, be tackled.

The offered pressure level of air compressors at gas stations for everyday bikes more than adequate, very usable with adapters or car valves. Not enough pressure is, however, for the very thin high-pressure bicycle tires.

Security

In a stand air pump that can inflate and Dunlop hose valves, appear much higher forces than with hand air pump, which usually only Dunlop valve Flash valves can be inflated.

In particularly cheap processed still air pumps, this can lead to breakage of the handle in the middle, which then transforms the rod into a dangerous projectile. It should always be taken when buying a stand air pump on the quality of the connection between the handle and piston rod, ideally form the handle and piston rod a massive unit.

Another source of error is the foot of the stand air pumps, with some also is a separate component with too short socket, which is connected with an industrial adhesive to the cylinder.