Claims
- 1. A method for controlling a probe including a transmission member and a transducer for generating mechanical oscillations and generating a standing wave on the transmission member, comprising:supplying a constant power to a transducer coupled to a transmission member and generating a standing wave on the transmission member; varying the frequency of oscillation of the transmission member coupled with said transducer by a first amount above a selected frequency; varying the frequency of oscillation of the transmission member by a second amount below the selected frequency; measuring the currents supplied to said transducer while the frequency is varied by the first and second amounts; and adjusting the frequency of oscillation according to the currents measured while the frequency is varied by the first and second amounts.
- 2. A control system for a probe coupled to a transducer constructed to oscillate at a selected frequency and impart oscillation to a transmission member, comprising:a power source for supplying a constant predetermined electrical power; a transducer coupled to the power source for converting the electrical power to oscillation at a selected frequency and coupled to a transmission member capable of supporting a standing longitudinal wave; a frequency adjustment device for measuring the frequency of the mechanical output of the transducer; and varying the frequency a selected amount above and below said selected frequency; a current monitoring device for measuring current supplied to the transducer which monitors said current while the frequency of said mechanical output is varied; and a processor operable to control the frequency adjustment device and the current monitoring device wherein under the control of the processor, wherein the frequency adjustment device varies the frequency of said mechanical output by a first amount above said selected frequency and by a second amount below said selected frequency and wherein the selected frequency is adjusted according to the currents monitored by the current monitoring device while the frequency adjustment device varies the frequency by the first amount and by the second amount.
- 3. The control system of claim 2, wherein said transmission member includes a wire or a rod.
- 4. The apparatus of claim 2, wherein said power generator is a 165 volt DC source.
- 5. The apparatus of claim 2, wherein said transducer is a piezoelectric transducer.
- 6. The apparatus of claim 2, wherein said selected frequency is approximately 42 kHz.
- 7. The apparatus of claim 6, wherein said frequency is varied at most ±500 Hz above and below said selected frequency.
- 8. The apparatus of claim 2, wherein said frequency adjustment device is a controller of a variable frequency generator.
- 9. The apparatus of claim 2, wherein said current monitoring device is a transformer.
- 10. The apparatus of claim 2, wherein said voltage measuring device is a transformer.
- 11. The apparatus of claim 2, wherein said frequency selector is a variable frequency generator.
- 12. A control system for a probe coupled to a transducer constructed to oscillate at a selected frequency and impart the oscillation to a transmission member, the control system comprising:a power source that supplies an electrical power; a transducer coupled to the power source to convert the electrical power to oscillations at a selected frequency and coupled to a transmission member capable of supporting a standing longitudinal wave; a frequency adjuster operable to vary the transducer output frequency; a current monitor that measures current supplied to the transducer while the frequency of the transducer output is varied by the frequency adjuster; and a processor coupled to and operable to control both the frequency adjuster and the current monitor, wherein under the control of the processor, wherein the frequency adjuster varies the frequency of the transducer output by a first amount in a first direction and by a second amount in a second direction opposite to the first direction while the current monitor measures the currents supplied to the transducer and wherein the selected frequency of the transducer output is adjusted according to the currents measured by the current monitor.
- 13. The control system according to claim 12, wherein under the control of the processor, the frequency variation by the frequency adjuster in the first and second directions and adjustment of the selected frequency are repeated continuously to optimize the oscillation amplitude.
- 14. The control system according to claim 12, wherein under the control of the processor, the frequency variation by the frequency adjuster in the first and second directions and adjustment of the selected frequency are repeated continuously to optimize the oscillation amplitude and the first and second amounts are each at most 500 Hz.
- 15. The control system according to claim 12, wherein the transmission member includes a wire or rod operable to oscillate by the transducer and coupled to the transducer for insertion into a human body.
Parent Case Info
This application claims priority of international application No. PCT/US98/10282, which has an international filing date of May 19, 1998, now abandoned.
PCT Information
Filing Document |
Filing Date |
Country |
Kind |
PCT/US98/10282 |
|
WO |
00 |
Publishing Document |
Publishing Date |
Country |
Kind |
WO98/53508 |
11/26/1998 |
WO |
A |
US Referenced Citations (44)
Provisional Applications (1)
|
Number |
Date |
Country |
|
60/046938 |
May 1997 |
US |