Soft start valve
US6079957A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 17, 1998 |
| Grant date | Jun 27, 2000 |
| Priority date | — |
| Expiry date | Nov 17, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/8733
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A fluid pumping apparatus (10) includes a soft start valve (16) coupled with the outlet of a pump (14) driven by an electric motor (12) for reducing the startup current of the motor (12). The preferred valve (16) includes a fluid chamber (32), a valve operator in the nature of a ball (22) shiftable in the chamber (32) between the inlet (36) and a valve seat (48), and a biasing assembly (24) including an axially shiftable rod (54) and a spring (56) for biasing the rod (54) against the ball (22) in order to bias the ball (22) toward the chamber inlet (36). Upon startup, the valve (16) provides a reduced start pressure, less than the pump pressure under load, at the inlet (36) as the operator (22) moves toward the seat (48). The chamber (32) presents a volume sufficient for the valve (16) to provide the start pressure long enough for the motor (12) to achieve synchronous speed, thereby reducing motor startup current.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.