Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
97 words
An equipment for use in surgical operations to remove tissue, comprising an ultrasonic knife having a tip intended to be brought into contact with the tissue, a transducer unit causing said tip portion to oscillate longitudinally and a frequency generator to drive the transducer unit, the parts of the ultrasonic knife which are in contact with the patient being galvanically isolated from the other equipment of the knife, as well as means for temporarily supplying high-frequency energy to the tissue from the tip portion of the ultrasonic knife in order to achieve hemostasis by means of coagulation.
Claim 2
Dependent Claim
97 words
An equipment for use in surgical operations to remove tissue, comprising an ultrasonic knife having a tip intended to be brought into contact with the tissue, a transducer unit causing said tip portion to oscillate longitudinally and a frequency generator to drive the transducer unit, the parts of the ultrasonic knife which are in contact with the patient being galvanically isolated from the other equipment of the knife, as well as means for temporarily supplying high-frequency energy to the tissue from the tip portion of the ultrasonic knife in order to achieve hemostasis by means of coagulation.
Claim 3
Dependent Claim
21 words
An equipment as claimed in claim 1, wherein the tip portion of the ultrasonic knife is provided with a central duct.
Claim 4
Dependent Claim
31 words
An equipment as claimed in claim 1, wherein the tip portion of the ultrasonic knife is arranged to cooperate with a duct for the supply of liquid, preferably a saline solution.
Claim 5
Dependent Claim
24 words
An equipment as claimed in claim 1, wherein the coagulation unit comprises means for emitting high-frequency electrical energy which induces heat in the tissue.
Claim 6
Dependent Claim
83 words
An equipment as claimed in claim 1, wherein the transducer is elongate and is manufactured as an integral unit with a substantially cylindrical portion (40), an intermediate portion (41) and a tapering tip portion (42) with a through bore (6) for aspirating comminuted tissue, the length of the transducer being in the order of magnitude 0,72 times the wavelength of the ultrasonic frequency, the intermediate portion having a geometric form corresponding to the fourth order Fourier curve and the tip portion being conical.
Claim 7
Dependent Claim
39 words
An equipment as claimed in claim 1, wherein the transducer (2) 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 8
Dependent Claim
58 words
An equipment as claimed in claim 1, comprising a voltage-controlled oscillator (50), a power amplifier (62) connected to the oscillator and a control loop for frequency control of the oscillator in response to the magnitude of a phase error between the current (I) and the voltage (U) for the energy the power amplifier feeds to the ultrasonic knife.
Claim 9
Dependent Claim
89 words
An equipment as claimed in claim 7, wherein the control loop comprises a ring core transformer with primary (63) and secondary (66) windings for the feed energy, a winding (72) arranged on the ring core transformer for sensing the voltage (U) of the feed energy, a current transformer (68) for sensing the current (I) of the feed energy and a phase comparator (74) for sensing the phase difference between said current and voltage and for feeding a direct voltage signal corresponding thereto to the control input of the oscillator.
Claim 10
Dependent Claim
110 words
An equipment as claimed in claim 8, wherein the current transformer(68) has a primary winding (67) provided with a central tap, with said tap connected to one end of the secondary winding (66) of the ring core transformer, one end of the primary winding (67) being connected to one plate of a compensation capacitor (69) and its other end being connected to one wire of a two-wire cord (4) connecting the ultrasonic knife to the frequency generator, the second plate of the compensation capacitor being connected to the other wire of the cord, this wire being connected to the other end of the secondary winding (66) of the ring transformer.
Claim 11
Dependent Claim
28 words
An equipment as claimed in claim 8, wherein the capacitance of the compensation capacitor (69) is selected such that it compensates the cable capacity of the two-wire cord.
Claim 12
Dependent Claim
78 words
An equipment as claimed in claims 8 - 10, wherein the secondary winding (66) of the ring core transformer is dimensioned to satisfy the equation: L² = f² · π² · C o ⁻¹ where L = the inductance (H) of the secondary winding (66) f = the frequency (Hz) of the feed energy C o = the capacitance of the ultrasonic knife the phase difference between I and U being zero degrees at the desired resonance frequency.
Claim 13
Dependent Claim
68 words
An equipment as claimed in claims 8 - 11, wherein the secondary winding (66) of the ring core transformer, the primary winding (67) of the current transformer and the compensation capacitor (69) are arranged in a screening housing (83) which is mechanically attached to the frequency generator chassis, whereby leakage currents to the power supply and other components meet the requirements of protective standard IEC-601-1, class body floating.