Automatic self-cleaning ferromagnetic metal detector
US4100491A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 28, 1977 |
| Grant date | Jul 11, 1978 |
| Priority date | — |
| Expiry date | Feb 28, 1997 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16N2210/04
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A ferrous metal detecting apparatus is disclosed for detecting metal particles in a flowing fluid, such as engine oil. The detecting apparatus has soft-iron pole pieces with a bridging gap therebetween. The soft-iron pole pieces are electrically insulated from each other and magnetized by direct current through an electromagnetic coil. After a sufficient amount of ferrous metal has accumulated on the bridging gap, a level detector will give a warning signal and cause the electromagnetic coil to degauss the soft-iron pole pieces by applying an alternating current to the electromagnetic coil. After the flowing fluid has washed away the ferrous metal, the direct current will remagnetize the soft-iron pole pieces. If repeated warning signals are within predetermined time intervals, an indication of the amount of ferrous metal contained in the fluid can be interpolated. The recycling for repeated warning signals may be automatically provided through a timing circuit and control logic.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.