| 摘要 |
<p>A multi-stage, reciprocable hand operable air pump (1) comprises a first and inner static cylinder (4); a piston (5) reciprocable within the inner cylinder (4) and carried by a piston rod (6) extending to a handle (3), a second and outer reciprocable cylinder (20) co-axially surrounds the inner cylinder (4) and has one closed end connected to the handle (3). A first annular chamber (22) is defined for receipt of a charge of air at atmospheric pressure upon reciprocation in a first direction, and for effecting a first compression upon reciprocation in the opposite direction. A static tube (23) is located co-axially between the inner static cylinder (4) and the reciprocable cylinder (20), to define an annular air admittance and transfer passage.</p> |
