Patent ID: 7181973
Filing Date: 2007-02-27
Classification: F04B,G01L

Abstract:
1. An air pump comprising: a hollow cylindrical casing having a reduced bottom opening and a top opening; a hollow cover mounted in the top opening of the cylindrical casing; a manometer movably received in the cylindrical casing to be selectively extended out of the cylindrical casing and having a groove defined in an outer periphery thereof to movably receive therein a first O ring and a cutout defined in a bottom face defining the groove; an air duct securely received in the manometer to be firmly engaged with an inner face defining the reduced bottom opening of the cylindrical casing; a tube provided to receive therein the air duct and to be received inside the manometer; a rod firmly mounted in a top opening of the tube and having an annular groove defined in an outer periphery to receive therein a second O ring; and a recoil spring mounted outside the manometer and having a top end abutted to a bottom face of the hollow cover and a bottom end abutted to the inner face defining the reduced bottom opening of the cylindrical casing such that in a situation where the first O ring is moved upward relative to a downward movement of the manometer to abut a top periphery of the groove, air inside a space defined by the manometer and cylindrical casing is able to flow through a gap between the manometer and the tube and into the air duct via a channel in the rod and into an object to be inflated, and in a situation where the manometer is extended out of the cylindrical casing, ambient air is able to flow through the hollow cover, an upper portion of a space between the manometer and the cylindrical casing divided by the first O ring, the cutout and into a lower portion of the space defined by the manometer and the cylindrical casing to be ready for a subsequent inflating process.