Metal detection apparatus
US10184908B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 15, 2016 |
| Grant date | Jan 22, 2019 |
| Priority date | — |
| Expiry date | Jul 13, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2200/541
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A metal detector has a transformer unit (1), a transmitter unit (2), a receiver coil set (3), a signal processing unit (4) and a control unit (5). The transformer unit provides an input signal (sIN) with selectable operating frequency (fTX) to an amplifier stage (12), that is connected to a transmitter coil (21) that is coupled to first and second receiver coils (31, 32). The coil outputs are connected to the signal processing unit, which has a receiver unit (41) and a signal processor (42). A coupling transformer (13) has first and second windings (13A, 13B), connected to the output of the amplifier stage, and a third winding (13C), connected to the transmitter coil. The first and second windings are each connected at a first end to a supply voltage (+Ub). Each of the first and second windings has at least one tapping (141, 142, 143, 144; 141′, 142′, 143′, 144′) at a same turn number counted from the first end. The amplifier stage has first and second amplification wings (12A, 12B). Each of these is associated with a power transistor connected to one of the at least one tappings of the corresponding winding, so the first and second amplification wings amplify the corresponding fir…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.