2-wire ultrasonic magnetostrictive driver
US9554871B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 18, 2015 |
| Grant date | Jan 31, 2017 |
| Priority date | — |
| Expiry date | Jul 21, 2035 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61C17/20
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A method for controlling a magnetostrictive ultrasonic transducer of the type used in a magnetostrictive ultrasonic dental scaler includes generating a drive signal for a resonant circuit using a full bridge synchronous class D amplifier. The electrical signal output by the resonant circuit drives an excitation coil that generates an electromagnetic field that causes the magnetostrictive ultrasonic transducer to vibrate. A feedback wire is rendered unnecessary by measuring current and voltage outputs of the resonant circuit and quadrature sampling the measured current and voltage outputs at the same sampling rate as used for the generation of the electrical signal by the resonant circuit. A pulse width modulated signal is generated from the quadrature sampled sensed current and voltage that represents a pulse train approximation of a sine wave of the drive signal for, in turn, being applied to the full bridge synchronous class D amplifier to generate the drive signal for the resonant circuit. Changes in the pulse widths of the pulse train change the amplitude of the drive signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.