Precompression metering-proportioning pump enabling its efficiency to be improved by early admission into the pump working space
US5176296A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 7, 1991 |
| Grant date | Jan 5, 1993 |
| Priority date | — |
| Expiry date | Aug 7, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/789
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Product admission into the working chamber 23 of a precompression pump is accelerated by providing a differential piston 4 with a bore 63 which establishes communication between the inside of a skirt 42 and a shoulder 44. A cylindrical sealing element 60 is fitted over a spindle 41 to be applied against the shoulder 44, level with two annular contacts 64, 65 between which the bore terminates. The sealing element closes the bore on discharge of the precompressed product dose. The sealing element is configured such that, particularly when the pump is idle, it is kept deformed and is therefore applied to the shoulder 44 with sufficient force to guarantee the seal of the two annular contacts 64, 65.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.