Reciprocating additive mixing pump apparatus and method
US5335734A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 4, 1993 |
| Grant date | Aug 9, 1994 |
| Priority date | — |
| Expiry date | May 4, 2013 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA62C11/00
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
A pump apparatus dispenses a liquid and additive mixture and has a pump cylinder with intake and discharge ports with associated valves. An additive supply communicates with the pump cylinder to supply additive with liquid drawn into the pump during an intake stroke prior to a discharge stroke during which a mixture of additive and liquid is discharged from the pump. The additive is mixed in the liquid prior to passing into the intake port and is metered to attain the desired concentration. An aerating nozzle receives mixture discharged from the discharge port to produce foam for various applications, such as fire fighting. The aerating nozzle has a restrictor orifice located adjacent and upstream from air entainment opening in the nozzle. The restrictor orifice can be a simple non-tapered cylindrical passage, but for improved foam generation, the orifice can be a diverging passage with a step between inlet and outlet portions of the passage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.