Precompression pump sprayer
US5638996A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 24, 1996 |
| Grant date | Jun 17, 1997 |
| Priority date | — |
| Expiry date | Oct 24, 2016 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB05B11/105
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A precompression pump sprayer comprises a hollow piston and a plunger rod having a discharge passage and a lower enlarged end forming a discharge valve seat, the rod extending through the piston for reciprocation between an inactive position and an end-of-stroke position, the piston engaging the valve seat in a discharge closed position, a primary spring biasing the plunger rod toward its inactive position, and a secondary spring biasing the piston into engagement with the discharge valve seat, the valve seat being of conical or curved shape, and the piston having a shoulder defining a discharge valve for solely contacting the valve seat along a thin circular line without sliding for quickly and cleanly valving the discharge passage open and closed during plunger actuation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.