John S Eberhardt

US Patent:

52314120, Jul 27, 1993

Filed:

Oct 18, 1991

Appl. No.:

7/780663

Inventors:

John E. Eberhardt - Plantation FL
Oscar M. Garay - Coral Springs FL
Yew S. Tay - Plantation FL

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H01Q 9320
H01Q 11080

US Classification:

343790

Abstract:

An antenna (100) includes a quarter-wave monopole radiating element (110, 110') having a signal feed point end (110A). The antenna (100) further includes a reactive element (150) in the form of a conductive sleeve. The sleeve (150) includes a grounding end (150A) and is coaxially positioned around a portion of the monopole radiating element (110, 110'). A spacer (140) is coaxially situated between the monopole radiating element (110, 110') and the reactive element (150), for electrically insulating the monopole radiating element (110, 110') from the reactive element (150). The spacer (140) is sufficiently dimensioned such that the monopole radiating element is tightly coupled to the reactive element (150) at substantially around the feed point end (150A).

US Patent:

55979742, Jan 28, 1997

Filed:

Mar 4, 1996

Appl. No.:

8/610025

Inventors:

Wallace E. Voreck - Sparta NJ
James E. Brooks - Manvel TX
John R. Eberhardt - Houston TX
Hooshang A. Rezaie - Houston TX

Assignee:

Schlumberger Technology Corporation - Houston TX

International Classification:

F42B 102

US Classification:

102307

Abstract:

A shaped charge includes a main body of explosive and a primer adapted to detonate said main body of explosive. In accordance with the present invention, the main body of explosive now includes an explosive composition known as sym-triaminotrinitrobenzene (TATB) and, since TATB is not sensitive enough to be a primer, the primer must consist of an explosive composition which is more sensitive than TATB. It has been discovered that, when the main body of explosive in a shaped charge is modified to include the explosive composition known as TATB and when the primer includes an explosive other than TATB, such as HNS or NONA or PYX or HMX, or a mixture of HNS or NONA or DODECA or PYX or HMX and TATB and when the shaped charge is detonated, the detonated charge will produce a jet that is longer in length than the jet associated with prior art shaped charges which did not have a main body of explosive that included TATB. As a result, when the longer jet is produced from the shaped charge of the present invention, that has been modified to include a main body of explosive comprising TATB and a primer which is more sensitive than said TATB, the longer jet will produce a longer perforation in a formation penetrated by a wellbore and, as a result, an increased quantity of wellbore fluid will be produced from the perforated formation. A detonating cord could also include the TATB explosive.