| 摘要 |
Air pump for inflating small objects such as a bicycle tyre comprises an elongate chamber (80) and a piston (73) slidable in said chamber between a first position and a second position, said chamber having cross-sections of different cross-sectional areas and differing circumferential lengths at the first and second positions, and at least substantially continuously different cross-sectional areas and circumferential lengths at intermediate positions between the first and second positions, the cross-sectional area and circumferential length at said second position being smaller than the cross-sectional area and circumferential length at said first position. Said air pump further comprises a hose (118) communicating the air pump exit valve with a valve on the object to be inflated. The hose comprises an expansion chamber (123) which permits variation of the volume inside the hose. |
