Dispenser with piston assembly for expelling product
US5042696A · kind A · utility
Inventor
Key dates
| Filing date | Aug 30, 1990 |
| Grant date | Aug 27, 1991 |
| Priority date | — |
| Expiry date | Aug 30, 2010 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB65D83/75
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A dispenser comprises an inner cylinder defining a contents chamber. A discharge valve is disposed at one longitudinal end of the chamber. A piston assembly disposed in the chamber is displaceable toward the valve for pressurizing the contents of the chamber. The piston includes longitudinally spaced ejector and energizer members with compressible air disposed therebetween for storing and transmitting energy from the energizer member to the ejector member. The air is confined by the sealing action of the ejector and energizer members against the inner cylinder. Alternatively, the air may be contained within a flexible enclosure extending between the ejector and energizer members, in order to avoid migration of air through the inner cylinder.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.