Patent US4577500A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4577500A Expired / Lapsed US ⏱️ 0.0 years remaining

Driving control method of ultrasonic transducer

Assignee: Taga Electric Co Ltd
•
Filing: 1984-08-01
•
Granted: 1986-03-25
•
Expires: 2004-08-01
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract In an ultrasonic transducer, frequency characteristics of phase detecting signal and frequency characteristics of transducer drive current are searched, the resonant point with current dipping is found on the characteristics, the zero cross point corresponding to the current dipping is decided as the fundamental resonant point, and then a PLL following oscillation operation is performed. Under such condition even if there exist many sub resonant frequency points near the fundamental resonant frequency, the PLL follow oscillation can be performed stably.

Inventors

  • 👤 Shoji Mishiro

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 13:45
CPC Classifications
B; B06; B06B; B06B1/00; B06B1/02; B06B1/0207; B06B1/0223; B06B1/0238; B06B1/0246; B06B1/0261; B06B2201/00; B06B2201/50; B06B2201/57; H; H04; H04R; H04R17/00; H04R17/04; H04R17/08

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 107 words
A driving control method for an ultrasonic transducer, comprising the steps of: measuring the transducer currents and determining the transducer current characteristics; locating the resonant points of the operation of said transducer based upon said current characteristics; determining the vibratory velocity detecting signal of said transducer based upon said transducer currents; determining the phase characteristics of said vibratory velocity detecting signal with respect to said transducer currents; determining the fundamental resonant point based upon the relationship of zero cross points of said phase characteristics with respect to the location and current value of said resonant point; and performing a phase lock-loop control oscillation to drive said transducer.
Claim 2
Dependent Claim 107 words
A driving control method for an ultrasonic transducer, comprising the steps of: measuring the transducer currents and determining the transducer current characteristics; locating the resonant points of the operation of said transducer based upon said current characteristics; determining the vibratory velocity detecting signal of said transducer based upon said transducer currents; determining the phase characteristics of said vibratory velocity detecting signal with respect to said transducer currents; determining the fundamental resonant point based upon the relationship of zero cross points of said phase characteristics with respect to the location and current value of said resonant point; and performing a phase lock-loop control oscillation to drive said transducer.
Claim 3
Dependent Claim 45 words
A driving control method according to claim 1 wherein said ultrasonic transducer includes two transducer elements each outputting a transducer current and wherein the step of determining the vibratory velocity detecting signal includes the step of summing signals proportional to each of said transducer currents.
Claim 4
Dependent Claim 117 words
A driving control method for an ultrasonic transducer, comprised in the steps of: measuring transducer currents and determining transducer current characteristics; determining resonant points of said transducer based on said transducer current characteristics; producing a vibratory velocity detecting signal derived from said measured currents and measuring the phase characteristics of said signal; determing the fundamental resonant point based upon the zero cross points of the phase characteristics; controlling said phase characteristics; controlling said phase characteristics of said velocity detecting signal so that said characteristics are made symmetric with respect to said fundamental resonant point on the high frequency side and the low frequency side of said fundamental point; and performing a phase-lock-loop oscillation operation of said transducer.
Claim 5
Dependent Claim 117 words
A driving control method for an ultrasonic transducer, comprised in the steps of: measuring transducer currents and determining transducer current characteristics; determining resonant points of said transducer based on said transducer current characteristics; producing a vibratory velocity detecting signal derived from said measured currents and measuring the phase characteristics of said signal; determing the fundamental resonant point based upon the zero cross points of the phase characteristics; controlling said phase characteristics; controlling said phase characteristics of said velocity detecting signal so that said characteristics are made symmetric with respect to said fundamental resonant point on the high frequency side and the low frequency side of said fundamental point; and performing a phase-lock-loop oscillation operation of said transducer.
Claim 6
Dependent Claim 45 words
The driving control method according to claim 3 wherein said ultrasonic transducer includes two transducer elements each outputting a transducer current and wherein the step of determining the vibratory velocity detecting signal includes the step of summing signals proportional to each of said transducer currents.

References Cited (Backward Citations)

US4114454A Cited
US4470306A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-03-24 1989-09-23 1990-03-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-03-24 1993-09-23 1994-03-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-03-24 1997-09-23 1998-03-25 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag