Thomas Francis Callahan

US Patent:

6438238, Aug 20, 2002

Filed:

Jul 14, 2000

Appl. No.:

09/616244

Inventors:

Thomas F. Callahan - Grantham NH 03753

International Classification:

A61B 704

US Classification:

381 67, 181131, 600528, D24134

Abstract:

A chest piece for a stethoscope has a housing with a cavity. The cavity has a cavity surface which is paraboloid in shape, having an apex, an axis, and a focal point. The cavity terminates at the apex and an opening, and the focal point resides in the cavity. A transducer is positioned at the focal point. The parabolic shape of the cavity surface acts to reflect sound waves transmitted normal to the opening to the transducer, while reflecting other sound waves. A mechanical wave guide with a series of parallel passages preferably extends across the opening. Preferably, a membrane with a convex surface covers the opening. The cavity is preferably filled with a liquid or gel having physical characteristics similar to human flesh. To reduce noise from motion of the chest piece across the skin, the stethoscope can be activated by a pressure switch responsive to fluid pressure inside the cavity.

US Patent:

7162039, Jan 9, 2007

Filed:

Mar 10, 2000

Appl. No.:

09/522834

Inventors:

Thomas F. Callahan - Grantham NH, US

International Classification:

A61B 7/04

US Classification:

381 67, 381380, 381374

Abstract:

The present invention provides a noise barrier apparatus for inhibiting external noise from causing the presence of noise in an audio chamber defined by a noise barrier device and including the user's ear canal. The noise barrier apparatus may be constituted by an in-ear noise barrier device or devices or an over-the-ear device or devices. An in-ear application of the present invention provides an in-ear-canal audio receiver comprising an in-ear-canal adapter body having a tapered ear plug portion that is inserted into the user's ear canal. The adapter body further has an opening in the plug portion, an exterior annular indent, and an inner chamber coupled to the opening of the plug portion. The inner chamber of the in-ear-canal adapter body holds a transducer assembly comprising a transducer housing and a transducer or speaker. The transducer is positioned in a passage extending through the transducer housing.

US Patent:

61636150, Dec 19, 2000

Filed:

Aug 6, 1998

Appl. No.:

9/129797

Inventors:

Thomas F. Callahan - Grantham NH

Assignee:

University Research & Engineers & Associates, Inc. - Grantham NH

International Classification:

H04R 2500

US Classification:

381371

Abstract:

The present invention provides an audio seal for use in an ear cup assembly. The audio seal has a generally torus-shaped body made from a compressible material. The torus-shaped body has a generally elliptical, torus configuration over approximately two-thirds to three-quarters of its perimeter and has a head and neck pad section that covers approximately one-quarter to one-third of said body's perimeter. The head and neck pad section protrudes forwardly and radially outward to form a bulging section that deviates the said elliptical, torus configuration.