Abstract: An electrosurgical generator control responds to tissue impedance between active and return electrodes during desiccation. Active and return generator leads to supply energy and a user control sets the level of energy desired for electrosurgery. Voltage and current sensing circuits respond to high frequency energy in the leads to signal voltage and current in the leads. A multiplier receives the signals to calculate power. A clock sets units of time during for which power calculation. An integrator calculates the energy supplied through the leads per time unit. The user control sets a reference signal for the energy level desired. A correlation circuit receives the energy calculations from the integrator and the reference signal and provides a feedback signal to indicate when the energy calculation equals the user control setting for altering the generator supply of energy to the leads.

Abstract: A control responds to impedance and temperature between active and return electrodes of the electrosurgical generator during tissue desiccation. Tissue contacts separately and independently provide high frequency power to effect tissue electrosurgically. An instantaneous impedance monitor between each contact and the return electrode signals. A regulator receives the signals and separately and independently controls tissue impedance at each contact in accord with signals to change independently the power to the return electrode. A temperature sensor for each contact transmits its temperature to the generator to regulate power to each contact. A first multiplexer provides high frequency electrosurgical power separately and independently to each contact from the generator. A second multiplexer relays temperature amounts of each contact to the generator.

Abstract: An active electrode switches from a monopolar mode extending from a handpiece and a patient return to a bipolar mode with the active and return electrodes extending. An active lead selectively connects the active output and the active electrode. A return lead selectively connects the return electrode and the return output in the monopolar mode or the return terminal when in the bipolar mode. Terminals connect with wiring to the electrodes to complete the circuit for the bipolar mode. One terminal is on the generator and one is in the handpiece to connect to the electrodes and complete the circuit for bipolar. The electrode has a control on the handpiece for the surgeon to change circuitry and to position the electrode for each mode. The return electrode in the monopolar mode is in the handpiece disconnected from its terminal. The return electrode connects to its terminal when extended from the handpiece but for monopolar a pair of patient pads connected to a monitoring circuit test continuity.

Abstract: An electrosurgical control for a trocar has a trocar with a cannula with a stylet coaxially fit therein. The stylet is movable relative to the cannula along a common axis. The trocar is shaped for insertion in a direction generally along the axis through tissue in a puncture procedure with its stylet. A distal end and a proximal end on the elongate cannula so the distal end enters the tissue while the proximal end remains outside. A tip on the stylet end, near the distal end of the cannula, normally extends therebeyond in position to puncture the tissue. The stylet has an energy supply passing from the tip to its opposite end and moves reciprocally relative to the cannula so the tip extends or is fully within the cannula. An electrosurgical generator provides energy to the opposite end of the stylet and an electrosurgically active device is a part of the tip and connects to the energy supply.

Abstract: An ultrasonic oscillator drives a tool at a set frequency. An amplitude control runs the oscillator to set the vibration level. A frequency regulator joins the amplitude and the oscillator. A control feedback loop, in the frequency regulator, keeps handpiece linear dynamics. An operational transconductance amplifier, in the oscillator, governs gain of the loop. A circuit connects to the control to retard the rate of current application over time to the amplifier. The circuit has switching to either retard the rate or reset for start up. The amplifier is a current output device with current directly proportional to the bias current and input voltage with bias as gain change for the loop. The circuit limits the bias to the amplifier to modify frequency response and output current. A capacitor delays application of the bias to the amplifier. Replaceable tools of various lengths or shapes positioned along an axis vibrate for surgery at the frequency and a wave length.

Abstract: Apparatus and method find leakage due to tissue load or transients and has active and return electrodes for RF energy sensed by transformers for a circuit that finds leakage at more than two thousand times per second or a frequency dependent on the phase shift between voltage and current. Software and feedback manage V.sub.rms to reduce the voltage or increase the crest factor, which is V.sub.rms divided by peak voltage, by pulse width modulation of the RF drive. Voltage and current phase shift changes, angle .theta., are compared to a threshold, and when greater, the frequency at which the differences between the active and return current signals are examined is increased. The differences between the active and return currents are examined and when greater than maximum leakage while in coagulation mode, the RF drive pulse width is reduced to maintain voltage wave peaks at a preset value and reduce V.sub.rms thereby reducing leakage to the allowable maximum.

Abstract: A circuit, for monitoring and controlling parameters of an electrosurgical unit, ESU, relative to load and the RF energy, has a load responsive output sensing circuit that measures the ESU load. A signal modifier, attached to the sensing circuit enhances the signals measured and transmits them to a buffer. An analog to digital converter, A/D, digitize the signals and samples wave pulse train at about eight million samples per second. A data memory stores the digitized signals. A RF drive clock connects to the ESU output; a sample clock uses phase shifting to interrogate the input signals to a processor, DSP, at a greater sampling rate of frequency than without. The DSP receives the stored signals from the data memory and processes them while monitoring and calculating ESU parameters measured, i.e.

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.

Abstract: Electrosurgical apparatus for performing at least cutting and coagulation of biological tissue, which comprises a hand operated electrosurgical pencil comprising an electrically insulated housing and an electrode with a distal end defining a tip, means for supplying high-frequency, alternating current, electrical energy from a generator through the electrode to the tissue and means for returning electrical energy from the tissue to the generator to complete an electrical circuit, switching means mounted on the housing for selecting the cut mode or the coagulating mode, which switching means is connected to an isolated low voltage, direct current circuit which provides an appropriate signal to control the generator in the cut mode or coagulating mode, respectively, whereby the generator supplies the desired high-frequency, alternating current, electrical energy to the electrode and current leakage is limited.

Abstract: An electrosurgical tubular trocar system has a hollow tube substantially longer than its diameter. The tube is shaped for insertion in a direction generally along its axis through tissue of a human or animal body. Distal and proximal ends on the tube enter and remain outside the tissue, respectively. A tip on the distal end punctures tissue of a human or animal. An insulating portion of high dielectric material extends along the tube between the distal and proximal ends. An electrode on the insulating portion extends from the proximal end to the tip to transmit radio frequency energy. An energy supply at the electrode proximal end permits the passage of energy to the tip. An electrosurgical generator as part of the energy supply has a control to regulate the amplitude and frequency of the energy. A return path in circuit with the tip and the energy supply cuts and/or coagulates. A tip point at an acute angle to the axis lessens the initial force necessary for entry of the tube.

Abstract: A device for enhancing the safety and efficiency of a hand-operated electrosurgical pencil having an exposed electrode with a distal end defining a tip for cutting biological tissue, which device comprises a nose piece adapted to be mounted about said electrode and defining at least one pathway for a stream of gas which shrouds the electrode at or near the tip thereof, and electrosurgical apparatus incorporating the device and a method for cutting biological tissue using the apparatus.

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.

Abstract: A device for enhancing the safety and efficiency of a hand-operated electrosurgical pencil having an electrode with a distal end defining a tip for cutting or coagulating biological tissue, which device comprises a nose piece adapted to be mounted about said electrode and containing conduit means defining converging pathways for streams of gas which impinge obliquely on said electrode at or near the tip thereof, and electrosurgical apparatus incorporating said device and a method for coagulating or cutting biological tissue using said apparatus.

Abstract: An electrosurgical generator including a patient circuit including an active electrode and a return electrode; a pulse train generating circuit an M.times.N storage device having M memory locations where M>1 and where each location contains N storage positions where N.gtoreq.1, the storage device storing at least one, K-bit binary signal, where 1<K.ltoreq.M, the bits of which are respectively stored in the Jth storage positions of K of the M memory locations where J.ltoreq.N; an output circuit for sequentially outputting the K-bit binary signal from the storage device; the electrosurgical generator being sequentially responsive to the sequentially outputted bits of the K-bit binary signal for generating an electrosurgical signal and applying this signal to the patient circuit. The storage device may take the form of one or more shift registers or EPROM's for example.