Patents by Inventor Dennis A. Brumwell

Dennis A. Brumwell has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6898463
    Abstract: A method and an apparatus for performing a device component failure analysis in an implantable medical device using current consumption data. A current consumption signal relating to current consumption in an implantable medical device is generated. The current consumption signal is then processed. A defect of a component in the implantable medical device is assessed in response to the processing of the current consumption signal and appropriate action is taken, such as selecting alternate therapies, generating an alert signal, and turning off circuits corresponding to the assessed defect.
    Type: Grant
    Filed: March 19, 2002
    Date of Patent: May 24, 2005
    Assignee: Medtronic, Inc.
    Inventors: Frank R. Dropps, Dennis A. Brumwell
  • Publication number: 20030181953
    Abstract: A method and an apparatus for performing a device component failure analysis in an implantable medical device using current consumption data. A current consumption signal relating to current consumption in an implantable medical device is generated. The current consumption signal is then processed. A defect of a component in the implantable medical device is assessed in response to the processing of the current consumption signal and appropriate action is taken, such as selecting alternate therapies, generating an alert signal, and turning off circuits corresponding to the assessed defect.
    Type: Application
    Filed: March 19, 2002
    Publication date: September 25, 2003
    Inventors: Frank R. Dropps, Dennis A. Brumwell
  • Patent number: 6035235
    Abstract: An amplified, isolated output control circuit is provided for controlling the output switching network of a self-powered defibrillator that delivers a high voltage electrical countershock through a plurality of electrodes. The defibrillator comprises a low voltage battery system, a high voltage capacitor system, a high voltage transformer connected between the battery system and the capacitor system, and an output switching network, such as an H-bridge switching network, connected between the capacitor system and the plurality of electrodes. The defibrillator is controlled by control circuitry that manages the charging and discharging of the electrical countershock and is connected to the output control circuitry. Preferably, the output control circuitry includes an isolated power supply, at least one optoisolator device and at least one amplifier circuit that is powered by the isolated power supply and is connected between the optoisolator device and a switch of the output switching network.
    Type: Grant
    Filed: March 30, 1998
    Date of Patent: March 7, 2000
    Assignee: Angeion Corp.
    Inventors: Joseph Perttu, Dennis Brumwell
  • Patent number: 5814090
    Abstract: An implantable medical device, such as an implantable cardioverter defibrillator (ICD), utilizes a heat-shrink conforming shield to substantially isolate internal components and circuitry from the device housing and from each other. Preferably, the shield also protects the internal circuitry of the device from undesirable electro-magnetic coupling effects. The shape conforming isolation material provides an inexpensive, effective isolation barrier that helps shield the circuitry from undesired coupling effects and also protects the components from inadvertent shorts as well as potential damage during assembly and testing.
    Type: Grant
    Filed: November 18, 1996
    Date of Patent: September 29, 1998
    Assignee: Angeion Corporation
    Inventors: Scott T. Latterell, Dennis Brumwell
  • Patent number: 5749910
    Abstract: An implantable cardioverter defibrillator capable of subcutaneous positioning within a patient delivers at least one electrical cardioversion/defibrillation countershocks to the heart of the patient. The implantable cardioverter defibrillator includes a housing, circuitry positioned within the housing to control delivery of the countershocks, and an energy source coupled with the circuitry to provide electrical energy to a capacitor in the circuitry that stores the electrical energy for delivery of the countershocks. Because the circuitry is susceptible to undesirable electromagnetic coupling effects of origin external to the circuitry, particularly the capacitive coupling effects between the circuitry and the housing of the device when at least a portion of the housing is utilized as an electrode, the implantable cardioverter defibrillator also includes a conductive shield, disposed between the housing and the circuitry, to shield the circuitry against such undesired coupling effects.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: May 12, 1998
    Assignee: Angeion Corporation
    Inventors: Dennis A. Brumwell, Joseph S. Perttu, Mark W. Kroll, Randall S. Nelson
  • Patent number: 5709215
    Abstract: An ICD detection method for sensing the occurrence of an R-wave improves the ability to distinguish R-waves from noise through the use of variable declining sensitivity thresholds. The method includes the consideration of the amplitude of at least the previous most recent R-wave to determine a declining threshold of sensitivity used to recognize a subsequent electrical signal as an R-wave. In the method, the amplitude of the previous R-wave may be classified, based upon amplitude, and based upon the classification, a desirable time constant for the declining threshold of sensitivity is provided as an exponential or reverse exponential decay. Alternatively, a piece wise use of various decay formulas may be combined and used to avoid false recognition of noise as an R-wave.
    Type: Grant
    Filed: September 6, 1995
    Date of Patent: January 20, 1998
    Assignee: Angeion Corporation
    Inventors: Joseph S. Perttu, Dennis A. Brumwell, James E. Brewer, Theodore P. Adams
  • Patent number: 5674248
    Abstract: A staged energy storage system provides electrical energy to an implantable biomedical device by using the combination of a first stage energy source and a second stage energy concentration system. The second stage energy concentration system allows a lower density and/or lower voltage energy source to be used as the first stage energy source, thereby decreasing the battery cost, size and weight. In one embodiment, the second stage energy concentration system comprises a rechargeable battery. In another embodiment, the second stage energy capacitor system comprises a high energy density capacitor system. The staged energy storage system is ideal for internally charging a pulse-generating capacitor system within an implantable cardioverter defibrillator. In this embodiment, a high voltage transformer has a secondary side that is electrically connected to the pulse-generating capacitor system.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: October 7, 1997
    Assignee: Angeion Corporation
    Inventors: Mark W. Kroll, Dennis A. Brumwell, Ann M. Donohoo
  • Patent number: 5620464
    Abstract: A main energy delivery electrical circuit for use in an implantable cardioverter defibrillator device comprises a low power output primary defibrillator battery, a high power output intermediate power intensifying capacitor system, a switch for permitting the intermediate power intensifying capacitor system to rapidly charge a main energy delivery capacitor, and a main energy delivery capacitor. The main energy delivery capacitor is configured for discharging, in a first pulse, an electrical charge derived from the primary battery, and for discharging certain subsequent pulses of electrical charge derived from the intermediate power intensifying capacitor system. The circuit permits the implantable cardioverter defibrillator device to deliver multiple closely spaced defibrillation pulses to a heart.
    Type: Grant
    Filed: January 23, 1995
    Date of Patent: April 15, 1997
    Assignee: Angeion Corporation
    Inventors: Mark W. Kroll, Dennis A. Brumwell, Ann M. Donohoo
  • Patent number: 5507781
    Abstract: The present invention uses switches to set the topology and polarity of a circuit that includes capacitors to deliver an electric pulse to a heart during a defibrillation procedure. The waveform of the electric pulse is biphasic, in that it is a positive portion of the pulse followed by a negative portion of the pulse. The topology and polarity of the circuit are utilized to produce a waveform that approximates the ideal waveform for the specific situation. The circuit provides for combinations of capacitors variously in series and in parallel and changing the topology and polarity of the circuit during discharge of the capacitors.
    Type: Grant
    Filed: August 18, 1994
    Date of Patent: April 16, 1996
    Assignee: Angeion Corporation
    Inventors: Mark W. Kroll, Theodore P. Adams, Dennis A. Brumwell
  • Patent number: 5411526
    Abstract: The first embodiment of the present invention repositions the shunt thyristor used in the monophasic-waveform generator of the prior art so that it discharges the main capacitor through a series thyristor, thus increasing current through it briefly, rather than reducing current through it. The result of this arrangement is that the node between the series thyristor and the heart is pulled rapidly to a low voltage, causing the shunt switch to discharge the cardiac capacitance, as well as the main capacitance. The consequence is that discharging the cardiac capacitance requires a reversal of current in the heart, which enhances the heart-stimulating effect of the defibrillating waveform. The resulting true-voltage-pulse waveform has an efficacy approximating that of a biphasic waveform and is achieved with a circuit no more complex than that used to generate a monophasic waveform.
    Type: Grant
    Filed: March 24, 1992
    Date of Patent: May 2, 1995
    Assignee: Angeion Corporation
    Inventors: Mark W. Kroll, Charles G. Supino, Theodore P. Adams, Dennis A. Brumwell
  • Patent number: 5372605
    Abstract: An improved dual battery power system uses two separate battery power sources for an implantable cardioverter defibrillator, each having optimized characteristics for monitoring functions and for output energy delivery functions, respectively. The monitoring functions are supplied electrical power by a first battery source, such as a conventional pacemaker power source in the form of a lithium iodide battery which is optimized for long life at very low current levels. The output energy delivery functions are supplied by a separate second battery source, such as a pair of lithium vanadium pentoxide batteries, which is optimized for high current drain capability and low self-discharge for long shelf life. The first battery source provides electrical power only to the monitoring functions of the implantable cardioverter defibrillator, and the second battery source provides all of the electrical power for the output energy delivery functions.
    Type: Grant
    Filed: August 16, 1993
    Date of Patent: December 13, 1994
    Assignee: Angeion Corporation
    Inventors: Theodore P. Adams, Dennis A. Brumwell, Joseph S. Perttu, Charles G. Supino
  • Patent number: 5312454
    Abstract: A monitoring system for an oxygen sensing, dual-wavelength, reflectance oximetry based, rate responsive cardiac pacemaker, is capable of automatically and continually adjusting an oxygen sensor signal comparator threshold such that the effects of noise, sensitivity and drift on oximeter output signals sent to the pacemaker are minimized. A comparator and related circuitry are configured to sample and compare supply excitations for multiple oxygen sensor light sources. The comparator threshold is adjusted as a function of supply excitation for each light source independently of one another, thereby providing an oxygen sensing pacemaker with optimal noise immunity since one of the more vulnerable portions of the pacing system is the transfer of the light source signals which are susceptible to noise.
    Type: Grant
    Filed: December 14, 1992
    Date of Patent: May 17, 1994
    Assignee: Medtronic, Inc.
    Inventors: Glenn M. Roline, Dennis A. Brumwell
  • Patent number: 5144755
    Abstract: A control system for a drying system of the type including a drying bin. Discharge particulate material moisture sensing means including a sensor assembly positioned in a discharge auger for sensing the moisture content of the particulate material. Control means is connected to the discharge particulate moisture sensing means and the discharge auger for controlling operation of the discharge auger.
    Type: Grant
    Filed: December 4, 1991
    Date of Patent: September 8, 1992
    Assignee: David Manufacturing Company
    Inventors: Keith Braun, Larry Stille, Dennis Brumwell
  • Patent number: 5129393
    Abstract: An improved atrial synchronous, dual chamber pacemaker provided with a variable refractory period during which the pacemaker is not responsive to the sensed atrial contractions. The atrial refractory period is varied as a function of measured atrial and ventricular rates, and corresponds to a predetermined proportion of the lesser of the average interval separating the ventricular contractions and the average interval separating atrial contractions. The invention is particularly beneficial in the context of a VDD type pacemaker.
    Type: Grant
    Filed: August 14, 1990
    Date of Patent: July 14, 1992
    Assignee: Medtronic, Inc.
    Inventor: Dennis A. Brumwell
  • Patent number: 4916830
    Abstract: A control system for a drying system of the type including a drying bin. Discharge particulate material moisture sensing means including a sensor assembly positioned in a discharge auger for sensing the moisture content of the particulate material. Control means is connected to the discharge particulate moisture sensing means and the discharge auger for controlling operation of the discharge auger.
    Type: Grant
    Filed: December 1, 1986
    Date of Patent: April 17, 1990
    Assignee: David Manufacturing Company
    Inventors: Keith Braun, Larry Stille, Dennis Brumwell
  • Patent number: 4903701
    Abstract: A demand pacemaker which regulates its pacing rate based upon sensed oxygen saturation percentage. The pacemaker employs a two wavelength reflectance oximeter as a sensor. The sensor includes an oscillator which sequentially activates red and infrared diodes. The duty cycle of the oscillator is regulated by the relative amounts of red and infrared light reflected by the blood. The construction of the sensor allows the sensor to operate with only two conductors, optimizing it for incorporation in a standard, bipolar pacing lead.
    Type: Grant
    Filed: March 10, 1988
    Date of Patent: February 27, 1990
    Assignee: Medtronic, Inc.
    Inventors: Alan A. Moore, Dennis A. Brumwell
  • Patent number: 4813421
    Abstract: A heart pacemaker including a two wave length reflectance oximeter for determining oxygen saturation. The pacing rate is increased or decreased in response to the measured oxygen saturation. By appropriate multiplexing and timing functions, the two wave length reflectance oximeter is included in a pacing lead coupled to the pacemaker which requires only three conductors.
    Type: Grant
    Filed: November 19, 1987
    Date of Patent: March 21, 1989
    Assignee: Medtronic, Inc.
    Inventors: Michael D. Baudino, Michael D. De Franco, Joseph F. Lessar, Dennis A. Brumwell, Gene A. Bornzin, Jeffrey A. Schweitzer
  • Patent number: 4807629
    Abstract: A heart pacemaker including a two wave length reflectance oximeter for determining oxygen saturation. The pacing rate is increased or decreased in response to the measured oxygen saturation. By appropriate multiplexing and timing functions, the two wave length reflectance oximeter is included in a pacing lead coupled to the pacemaker which requires only three conductors.
    Type: Grant
    Filed: November 19, 1987
    Date of Patent: February 28, 1989
    Assignee: Medtronic, Inc.
    Inventors: Michael D. Baudino, Michael D. De Franco, Joseph F. Lessar, Dennis A. Brumwell, Gene A. Bornzin, Jeffrey A. Schweitzer
  • Patent number: 4791935
    Abstract: A heart pacemaker including a two wave length reflectance oximeter for determining oxygen saturation. The pacing rate is increased or decreased in response to the measured oxygen saturation. By appropriate multiplexing and timing functions, the two wave length reflectance oximeter is included in a pacing lead coupled to the pacemaker which requires only three conductors.
    Type: Grant
    Filed: August 15, 1986
    Date of Patent: December 20, 1988
    Assignee: Medtronic, Inc.
    Inventors: Michael D. Baudino, Michael D. de Franco, Joseph F. Lessar, Dennis A. Brumwell, Gene A. Bornzin, Jeffrey A. Schweitzer
  • Patent number: RE38777
    Abstract: An improved dual battery power system uses two separate battery power sources for an implantable cardioverter defibrillator, each having optimized characteristics for monitoring functions and for output energy delivery functions, respectively. The monitoring functions are supplied electrical power by a first battery source, such as a conventional pacemaker power source in the form of a lithium iodide battery which is optimized for long life at very low current levels. The output energy delivery functions are supplied by a separate second battery source, such as a pair of lithium vanadium pentoxide batteries, which is optimized for high current drain capability and low self-discharge for long shelf life. The first battery source provides electrical power only to the monitoring functions of the implantable cardioverter defibrillator, and the second battery source provides all of the electrical power for the output energy delivery functions.
    Type: Grant
    Filed: December 13, 1996
    Date of Patent: August 16, 2005
    Assignee: Angeion Corp.
    Inventors: Theodore P. Adams, Dennis A. Brumwell, Joseph S. Perttu, Charles G. Supino