Submersible sump pump
US4396353A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 13, 1981 |
| Grant date | Aug 2, 1983 |
| Priority date | — |
| Expiry date | Apr 13, 2001 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04D15/0218
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A sump pump includes a submersible electric motor for driving an impeller which discharges water radially outward into a volute oriented in a horizontal plane at the bottom of the device. An optical sensor located at a predetermined pump-operating level utilizes the light reflecting and refracting properties of the sensor-chamber interface to sense the presence or absence of water at such level. In a first embodiment, the pump includes a supplementary water level-sensing chamber which has a first leg ascending from an inlet near its lower end to an overflow point at the top of a vertical barrier separating the first leg from a second leg which descends to the low pressure area of the impeller. The optical sensor is located at the overflow point such that the sensor will detect water and therefore activate the motor and the pump when the static water level is at least as high as the overflow point and will continue to detect water as the level subsequently drops because the pump will siphon water over the overflow point until the siphon is broken when the water level in the sump drops below the inlet of the first leg of the sensing chamber. When that occurs, the optical sensor will …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.