Compact manual air pump having selectable high volume and high pressure modes
US5676529A · kind A · utility
Inventors
Key dates
| Filing date | Jul 15, 1996 |
| Grant date | Oct 14, 1997 |
| Priority date | — |
| Expiry date | Jul 15, 2016 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04B33/005
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A pump comprises a pair of coaxial pistons, one slidably positioned in the other for simultaneous compression causing oppositely directed air flow, a passage having a valve for permitting air flow from one such piston to enter the other such piston for increased air flow, and a switching device for selectively opening the passage to ambient for preventing air flow between the pistons. The pump thus has two modes, namely, a high volume mode when the two pistons operate simultaneously to direct combined air flow and a high pressure mode when the passage is opened to ambient to direct air flow from only one of the two pistons having a smaller bore.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.