Patent US5062827A successfully refreshed from Google Patents.
US5062827A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device in ultrasonic aspirators
Assignee: SURGICAL TECHNOLOGY GROUP Ltd
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Filing: 1989-02-14
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Granted: 1991-11-05
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Expires: 2009-02-14
Abstract
Abstract Device in ultrasonic knives of the kind including a transducer for converting electrical energy at ultrasonic frequency to a mechanical oscillation. An amplitude transformer (2) forms the tip of the knife. The length of the ultrasonic transformer is in the order of magnitude 0.72 times the wavelength of the ultrasonic frequency. The ultrasonic transformer is an integral unit comprising a cylindrical portion (40), an integral portion (41) which is the curve of a wave function of the fourth order Fourier form, and a tip portion (42) which is conical, whereby the maximum stroke of the longitudinal oscillation mode of the knife is a desired resonance frequency, this resonance frequency being greatly separated, in the order of magnitude 20% with relation to the resonance frequency, from resonance frequency pertaining to harmonics of the desired resonance frequency in the longitudinal oscillation mode, and resonance frequency pertaining to oscillations in the transverse mode.
Inventors
- 👤 Hans Wiksell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 09:41
CPC Classifications
B; B06; B06B; B06B3/00; A; A61; A61F; A61F9/00; A61F9/007; A61F9/00736; A61F9/00745; A61B; A61B18/00; A61B18/04; A61B18/12; A61B18/1206; A61B17/00; A61B17/32; A61B17/320068; A61B2017/32007; A61B2017/320084; A61B2017/320089
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
184 words
In an ultrasonic knife device having a transducer means for converting electrical energy at an ultrasonic frequency to mechanical oscillations, an amplitude transformer means mechanically connected to the transducer means for amplifying the stroke of mechanical oscillation, wherein said amplitude transformer means is an elongated integral unit having a substantially cylindrical portion connected to the transducer neons an intermediate portion adjacent to the cylindrical portion, a tip portion adjacent to the intermediate portion, and a through bore passing through the intermediate portion and the tip portion for aspirating tissue, the improvement wherein the length of the amplitude transformer means is 0.72 times the wavelength of the ultrasonic frequency, and wherein the intermediate portion has geometric form which is the curve of a wave function of the fourth order Fourier form and the tip portion is conical, whereby the maximum stroke of the longitudinal oscillation mode is at a predetermined resonant frequency, this resonant frequency being separated, in order of magnitude of 20% from the harmonics of the predetermined resonant frequency in the longitudinal oscillation mode, and resonant frequencies of oscillations in the transverse mode.
Claim 2
Dependent Claim
184 words
In an ultrasonic knife device having a transducer means for converting electrical energy at an ultrasonic frequency to mechanical oscillations, an amplitude transformer means mechanically connected to the transducer means for amplifying the stroke of mechanical oscillation, wherein said amplitude transformer means is an elongated integral unit having a substantially cylindrical portion connected to the transducer neons an intermediate portion adjacent to the cylindrical portion, a tip portion adjacent to the intermediate portion, and a through bore passing through the intermediate portion and the tip portion for aspirating tissue, the improvement wherein the length of the amplitude transformer means is 0.72 times the wavelength of the ultrasonic frequency, and wherein the intermediate portion has geometric form which is the curve of a wave function of the fourth order Fourier form and the tip portion is conical, whereby the maximum stroke of the longitudinal oscillation mode is at a predetermined resonant frequency, this resonant frequency being separated, in order of magnitude of 20% from the harmonics of the predetermined resonant frequency in the longitudinal oscillation mode, and resonant frequencies of oscillations in the transverse mode.
Claim 3
Dependent Claim
42 words
An ultrasonic knife device as claimed in claim 1, wherein the amplitude transformer neons is made from a heat-treated alloy of titanium, aluminium, vanadium and iron with a hydrogen content of less than 0.3% and an oxygen content of less than 0.01%.
Claim 4
Dependent Claim
152 words
An ultrasonic knife device as set forth in claim 1 having a voltage controlled oscillator, a power amplifier connected to the oscillator and a control loop coupled to said voltage controlled oscillator for frequency control of the oscillator in response to the magnitude of a phase error between the current and voltage of the energy the power amplifier feeds to the ultrasonic knife, wherein the control loop includes a ring core transformer with primary and secondary windings for the feed energy, a winding arranged on the ring transformer for sensing the voltage of the feed energy, a current transformer coupled to the ring transformer for sensing the current of the feed energy and a phase comparator coupled to the ring transformer and the current transformer for sensing the phase difference between the current and voltage and for feeding a direct voltage signal corresponding thereto the to the control input of the oscillator.
Claim 5
Dependent Claim
118 words
An ultrasonic knife device as claimed in claim 3, including a compensation capacitor and a two wire cord wherein the current transformer has a primary winding provided with a central tap, with said tap connected to one end of the secondary winding of the ring core transformer, one end of the primary winding being connected to one plate of the compensation capacitor and the other end of the primary winding being connected to one wire of the two-wire cord connecting the ultrasonic knife to the frequency generator, the second plate of the compensation capacitor being connected to the other wire of the core, the other wire being connected to the other end of the ring transformer secondary winding.
Claim 6
Dependent Claim
30 words
An ultrasonic knife device as claimed in claim 4, wherein the capacitance of the compensation capacitor is selected such that it compensates for the capacity of the two wire cord.
Claim 7
Dependent Claim
64 words
An ultrasonic knife device as claimed in claim 4, wherein the secondary winding of the ring core transformer is dimensioned to satisfy the equation: L.sup.2 =f.sup.2 ·π.sup.2 ·C.sub.O.sup.-1 L = inductance (H) of the secondary winding f = feed energy frequency (Hz) C O = capacitance of ultrasonic knife, the phase difference between current and voltage being zero degrees at the desired resonant frequency.
Claim 8
Dependent Claim
51 words
An ultrasonic knife device as claimed in claim 4, including a housing and a frequency generator chassis wherein the secondary winding of the ring core transformer, the primary winding of the current transformer and the compensation capacitor are positioned in the housing which is mechanically attached to the frequency generator chassis.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-11-04 | 1995-05-06 | 1995-11-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-11-04 | 1999-05-06 | 1999-11-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-11-04 | 2003-05-06 | 2003-11-05 | $7700.00 | Window Closed / Lapsed |