Dennis K Larson

US Patent:

6868346, Mar 15, 2005

Filed:

Nov 27, 2002

Appl. No.:

10/306889

Inventors:

Dennis E. Larson - White Bear Township MN, US
Douglas R. Daum - Oakdale MN, US

Assignee:

Cardiac Pacemakers, Inc. - St. Paul MN

International Classification:

G01F001/00

US Classification:

702 45

Abstract:

A minute ventilation sensing device in which transthoracic impedance is measured to generate an impedance signal from which a ventilation signal is derived, where the ventilation signal is proportional to minute ventilation. An adaptive high pass filter is used to filter the impedance signal into a ventilation band. The pole frequency of the high pass filter is adjusted in accordance with changes in a calculated signal variation parameter.

US Patent:

7092757, Aug 15, 2006

Filed:

Jul 12, 2002

Appl. No.:

10/195135

Inventors:

Dennis E. Larson - White Bear Township MN, US
Douglas R. Daum - Oakdale MN, US

Assignee:

Cardiac Pacemakers, Inc. - Saint Paul MN

International Classification:

A61N 1/365

US Classification:

607 17, 607 18, 607 24

Abstract:

A minute ventilation sensing device in which transthoracic impedance is measured with a excitation current waveform at a specified amplitude and frequency. In order reduce interference with the impedance measurement from external noise sources, a noise detection operation may be performed with the amplitude and/or frequency of the excitation current waveform adjusted accordingly.

US Patent:

7409245, Aug 5, 2008

Filed:

Jan 30, 2007

Appl. No.:

11/668622

Inventors:

Dennis E. Larson - White Bear Lake MN, US
Prashant Rawat - Blaine MN, US
Daniel Kollmann - Andover MN, US

Assignee:

Cardiac Pacemakers, Inc. - St. Paul MN

International Classification:

A61N 1/375

US Classification:

607 36, 607 60, 343860

Abstract:

An implantable medical device may have an antenna for communication with external devices or other internal devices. Changes in the patient's body position, weight, composition or other factors may change the antenna efficiency and hinder communication. The disclosed circuit may automatically adjust a matching network for an implanted transceiver to dynamically maximize transmission and reception by controlling the selected value of a plurality of capacitors, inductors and resistors.

US Patent:

8174460, May 8, 2012

Filed:

Jul 30, 2008

Appl. No.:

12/182964

Inventors:

Dennis E. Larson - White Bear Lake MN, US
Prashant Rawat - Blaine MN, US
Daniel Kollmann - Andover MN, US

Assignee:

Cardiac Pacemakers, Inc. - St. Paul MN

International Classification:

H01Q 1/50

US Classification:

343861, 343860, 607 36, 607 60

Abstract:

An implantable medical device can include an implantable antenna for communication with external devices or other internal devices. Changes in the patient's body position, weight, composition or other factors may change the efficiency of the implantable antenna and hinder communication. The disclosed circuit can calculate a value for a matching network for an implantable telemetry circuit to decrease an impedance difference between the implantable telemetry circuit and the implantable antenna or increase or maximize a communication power transfer value associated with the implantable medical device.

US Patent:

20120130206, May 24, 2012

Filed:

Nov 22, 2011

Appl. No.:

13/302282

Inventors:

Sasidhar Vajha - Brooklyn Park MN, US
Keith R. Maile - New Brighton MN, US
Dennis E. Larson - White Bear Township MN, US
David A. Chizek - Brooklyn Park MN, US
John M. Edgell - Plymouth MN, US

International Classification:

A61B 5/07
H01P 11/00
A61N 1/36

US Classification:

600302, 607 60, 29600

Abstract:

Subject matter such as a method or apparatus can include an implantable antenna assembly, comprising a dielectric shell including first and second substantially parallel outer face portions, and a third outer face portion extending between the first and second portions, a spiral conductor extending along the first, second, and third portions on a surface of the dielectric shell. The dielectric shell and spiral conductor can be configured to be mechanically attached to a dielectric compartment, such as configured to be coupled to a housing of an implantable medical device. In an example, the implantable antenna assembly is configured to be electrically coupled to an implantable telemetry circuit configured to wirelessly transfer information electromagnetically using the implantable telemetry antenna, such as included as a portion of an implantable medical device.

US Patent:

20120130450, May 24, 2012

Filed:

Nov 22, 2011

Appl. No.:

13/302202

Inventors:

Sasidhar Vajha - Brooklyn Park MN, US
Keith R. Maile - New Brighton MN, US
Dennis E. Larson - White Bear Township MN, US
David A. Chizek - Brooklyn Park MN, US
John M. Edgell - Plymouth MN, US

International Classification:

A61N 1/36

US Classification:

607 60

Abstract:

In an example, an apparatus can include an implantable medical device comprising a housing, an implantable telemetry circuit carried within the housing, a dielectric compartment mechanically coupled to the housing, the dielectric compartment including first and second substantially parallel face portions and a third face portion extending between the first and second face portions, and an implantable telemetry antenna, located at least partially within the dielectric compartment. The implantable telemetry circuit can be electrically coupled to the implantable telemetry antenna and configured to wirelessly transfer information electromagnetically using the implantable telemetry antenna. In an example the implantable telemetry antenna comprises a spiral conductor portion extending along the first, second, and third face portions. In an example the spiral conductor includes a cross section having a lateral width that can be greater than a sidewall height of the cross section

US Patent:

20120130451, May 24, 2012

Filed:

Nov 22, 2011

Appl. No.:

13/302324

Inventors:

Sasidhar Vajha - Brooklyn Park MN, US
Keith R. Maile - New Brighton MN, US
Dennis E. Larson - White Bear Township MN, US
David A. Chizek - Brooklyn Park MN, US
John M. Edgell - Plymouth MN, US

International Classification:

A61N 1/36

US Classification:

607 60

Abstract:

Subject matter such as a method or apparatus can include an implantable medical device comprising a housing, an implantable telemetry circuit carried within the housing, and a dielectric compartment, mechanically coupled to the housing an implantable telemetry antenna, such as located at least partially within the dielectric compartment. The implantable telemetry circuit can be electrically coupled to the implantable telemetry antenna and configured to wirelessly transfer information electromagnetically using the implantable telemetry antenna. The implantable telemetry antenna can include a spiral conductor portion extending along a face portion of the dielectric compartment, and a loading portion configured to adjust an input impedance of the implantable telemetry antenna, to provide a specified input impedance range within a specified range of operating frequencies to be used for wireless information transfer.

US Patent:

42781183, Jul 14, 1981

Filed:

Jul 5, 1979

Appl. No.:

6/054802

Inventors:

Dennis L. Larson - Cottage Grove MN

International Classification:

B27L 700

US Classification:

144193A

Abstract:

The present invention relates to a log splitting apparatus utilizing a hydraulic cylinder mounted onto a main frame member and having a movable pusher portion that forces log sections against an upright cutting blade. The main frame member is tubular and also forms the hydraulic reservoir for the hydraulic system used with the cylinder. The entire splitter assembly is mounted onto mounting brackets which permit the splitter assembly to be placed onto a graden tractor with the axis of the power cylinder crossways to the longitudinal (fore and aft) axis of the garden tractor for compact assembly. The splitter assembly is self-contained and is powered directly from the power take-off of such garden tractor.