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    APPARATUS FOR LEAKAGE CONTROL AND METHOD FOR ITS USE
    32.
    发明专利
    APPARATUS FOR LEAKAGE CONTROL AND METHOD FOR ITS USE 未知

    公开(公告)号：CA2165186A1

    公开(公告)日：1995-02-09

    申请号：CA2165186

    申请日：1994-04-26

    Applicant: VALLEYLAB INC

    Inventor： KLICEK MICHAEL S ,  PATERSON WILLIAM G

    IPC: A61B18/12 ,  A61B17/39

    Abstract: An apparatus (10) and method to find leakage due to tissue load or transients at the start or end of electrosurgery. Active and return electrodes (11 and 16) between a patient and an ESU (13) pass RF energy sensed by inductive transformers (17 and 19). A circuit finds leakage at more than two thousand times per second; that frequency depends on the phase shift (23) between voltage and current. Software and feedback (26) manage RMS voltage to reduce the peak voltage of the output wave or increase the crest factor by pulse width modualtion of the RF drive. Phase shift (23) changes of the active and return current signals (18 and 20) and peak voltage and current are found. The phase angle .theta. is compared to a threshold and if greater than the frequency at which the differences (22) between the active and return current signals (18 and 20) are examined is increased. The differences (22) between the active and return current signals (18 and 20) are examined and if greater than a maximum for leakage while the mode selected is in coagulation then the pulse width of the RF drive is reduced to hold voltage wave-form peaks at a predetermined value while the RMS voltage is reduced to lower the leakage to a maximum or the frequency at which the leakage current is calculated is held to a maximum level until the phase angle is smaller than the threshold. If the difference (22) is greater than a maximum for leakage while the mode is cut or bipolar then the Vms is reduced to a maximum level or the level remains high until the phase angle .theta. is smaller than a threshold. The crest factor is increased by reducing the duty cycle or the pulse width of the output wave shape.

    34.
    发明专利
    未知

    公开(公告)号：NO934404D0

    公开(公告)日：1993-12-03

    申请号：NO934404

    申请日：1993-12-03

    Applicant: VALLEYLAB INC

    Inventor： KLICEK MICHAEL S ,  ZIEVE DAVID A

    IPC: A61B18/00 ,  A61B17/22 ,  A61B18/12 ,  A61M1/00 ,  A61B

    Abstract: An electrical circuit system which provides electrical energy to a surgical apparatus having ultrasonic fragmentation, aspiration and electrosurgical coagulation capabilities, which system also includes an impedance sensing network and automatic feedback power output control to reduce RF power output as load impedance increases, thereby reducing RF leakage current.

    36.
    发明专利
    未知

    公开(公告)号：FI935424A0

    公开(公告)日：1993-12-03

    申请号：FI935424

    申请日：1993-12-03

    Applicant: VALLEYLAB INC

    Inventor： KLICEK MICHAEL S ,  ZIEVE DAVID A

    IPC: A61B18/00 ,  A61B17/22 ,  A61B18/12 ,  A61M1/00 ,  A61B

    Abstract: An electrical circuit system which provides electrical energy to a surgical apparatus having ultrasonic fragmentation, aspiration and electrosurgical coagulation capabilities, which system also includes an impedance sensing network and automatic feedback power output control to reduce RF power output as load impedance increases, thereby reducing RF leakage current.

    Electrosurgical Bipolar Cutting Handpiece
    37.
    发明专利
    Electrosurgical Bipolar Cutting Handpiece 未知

    公开(公告)号：CA2130554A1

    公开(公告)日：1993-10-14

    申请号：CA2130554

    申请日：1993-01-11

    Applicant: VALLEYLAB INC

    Inventor： KLICEK MICHAEL S

    IPC: A61B18/14

    Abstract: An electrosurgical bipolar treating apparatus comprising a handpiece to which is connected a first active electrode and a second return electrode having exposed distal ends which define a bipolar tip for electrosurgically treating tissue at an operational site on a patient, which tip is structured so that both distal ends simultaneously contact said tissue and wherein the active electrode has a higher tissue to electrode impedance than the return electrode.

    DIGITAL WAVEFORM GENERATION FOR ELECTROSURGICAL GENERATORS
    38.
    发明专利
    DIGITAL WAVEFORM GENERATION FOR ELECTROSURGICAL GENERATORS 未知

    公开(公告)号：CA2220909C

    公开(公告)日：2001-02-27

    申请号：CA2220909

    申请日：1996-06-03

    Applicant: VALLEYLAB INC

    Inventor： KLICEK MICHAEL S ,  SODNICAR MATTHEW J

    IPC: A61B18/12 ,  A61B17/39

    Abstract: An electrosurgical generator (10) has an improved design for generating output waveforms using a microprocessor (15). The waveforms are generated in the form of a serial digital output from the microprocessor (15). The serial digital output is transformed into an electrosurgical RF output in an amplifier stage. The improved design also includes a monitoring circuit to continuously monitor the serial digital output by time-averaging the output, and then comparing that value with a threshold. The electrosurgical generator (10) comprises a microprocessor (15), an algorithm in the microprocessor (15) capable of toggling an output port of the microprocessor (15), an output amplifier (16), an adjustable high voltage DC power supply (17), a patient circuit including an active electrode (12) and a return electrode (13). The electrosurgical generator (10) may further comprise a mode selector (20) for selecting one of a plurality of pulse patterns in the serial digital output, and a plurality of command sequences in the algorithm, where each command sequence is designed to produce one of the plurality of patterns. There may also be a tank damp circuit (22) for reducing the amplitude of voltage spikes in the electrosurgical output, and a pulse suppression circuit. The monitoring circuit comprises a low pass filter (19) and a comparator to verify operation of the waveform generator.

    Electrosurgical generator power control circuit and method
    39.
    发明专利
    Electrosurgical generator power control circuit and method 未知

    公开(公告)号：AU699351B2

    公开(公告)日：1998-12-03

    申请号：AU6013496

    申请日：1996-06-28

    Applicant: VALLEYLAB INC

    Inventor： BECKER DANIEL J ,  KLICEK MICHAEL S

    IPC: A61B18/12 ,  A61B17/39

    Abstract: A constant power control circuit for an electrosurgical generator and a method for maintaining the electrical power output of an electrosurgical generator at a generally constant value throughout a given tissue impedance range are disclosed. The constant power control circuit and the method recognize and use the unique and simple linear characteristics associated with certain electrosurgical generator designs to monitor and control the electrical power output without having to calculate or monitor the actual output power. The constant power control circuit includes a current sampling circuit, a linear conversion circuit, and a feedback correction circuit. The constant power control circuit may also include protection circuitry that prevents the electrosurgical generator from being over-driven during high and/or low impedance loading, and reduces the severity of exit sparking by providing a quick response to high impedance indications while nonetheless maintaining increased power levels throughout a preset, nominal impedance range. The constant power control circuit and method may be included as an integral part of the overall electrosurgical generator's circuitry, or may be embodied as a separate unit that connects to, and controls, an electrosurgical generator. The constant power control circuit and method may be embodied through a variety of analog and/or digital circuit components or arrangements, including software running on computational and memory circuitry.

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