Resistance feedback controlled power supply
US5352868A · kind A · utility
69Cited by
15References
19Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 1, 1992 |
| Grant date | Oct 4, 1994 |
| Priority date | — |
| Expiry date | May 1, 2012 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B2018/00875
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A power supply for use with resistively-heated surgical instruments is provided, wherein accurate temperature regulation is achieved employing a resistance feedback circuit. The power supply powers the surgical instrument with an AC voltage waveform, and applies a fixed, low level DC signal to the heating element to produce a DC signal proportional to the instantaneous resistance of the heating element. The DC signal is compared to a setpoint value to obtain a control signal for adjusting the power delivered to the instrument to maintain a substantially constant heating element temperature, even under varying thermal loads.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.