Control system for calibrating and driving ultrasonic transducer
US5406503A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 30, 1992 |
| Grant date | Apr 11, 1995 |
| Priority date | — |
| Expiry date | Sep 30, 2012 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB06B2201/76
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
An electronic control system for determining the resonant frequency of and driving ultrasonic transducers in a phacoemulsification probe used for ophthalmic surgery. The control system includes a voltage control led oscillator, power amplifier, power monitor, and automatic gain control circuit operating under the direction of command signals received from a microprocessor-based control console. The control system operates in a constant apparent power, direct drive mode with closed loop feedback maintaining the electrical power provided to the primary of a RLC transformer at the constant level requested by the command signals from the console. The frequency of the drive signal is held at the dominant resonant frequency of the ultrasonic transducer which is being driven by the control system. This resonant frequency is determined via a calibration procedure performed when the probe is first attached to the control system. During this procedure a constant voltage drive signal is swept through a range of frequencies and the electrical power consumed by the transducer is measured and stored at selected intervals such as 100 Hertz increments. The resonant frequency is also determined in …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.