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A bicycle pump is a type of positive-displacement pump specifically designed for inflating bicycle tires. It has a connection or adapter for use with one or both of the two most common types of valves used on bicycles, Schrader or Presta. A third type of valve called the Woods valve exists, but tubes with these valves can be filled using a Presta pump.〔(Sheldon Brown's Bicycle Glossary W )〕 Several basic types are available: * Floor models or track pumps * Frame mounted * Compact or mini * Foot operated * Double action In its most basic form, a bicycle pump functions via a hand-operated piston. During the up-stroke, this piston draws air through a one-way valve into the pump from the outside. During the down-stroke, the piston then displaces the air from the pump into the bicycle tire. Most floor pumps, also commonly called track pumps, have a built in pressure gauge to indicate tire pressure. Electrically-operated pumps intended to inflate car tires (as available in most service stations) can in principle be used to inflate a bicycle tire if the right type of connection is available. Some such pumps are designed to cut off before a suitable pressure (much higher for a bicycle than a car tire), and will much underinflate the tire. Others may not cut off, but deliver a high rate of flow to fill the larger car tire, with a risk of overinflating and bursting a bicycle tire unless it is stopped with split-second timing. ==History== No day has been established as to when the first bicycle pump was invented, but it is believed to have been in or around 1887, which is when the first inflatable tire or pneumatic tire was produced by John Boyd Dunlop of Scotland. The first bicycle pump consisted of a metal cylinder that had a metal rod running down the middle of it. This would have of forced the air out of the cylinder and then sucked in new air when the metal rod was pulled up again. Many modern pumps use a very similar method, while some, such as the electric pumps, use an automated pumping mechanism. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「bicycle pump」の詳細全文を読む スポンサード リンク
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