David D Hart

US Patent:

49075241, Mar 13, 1990

Filed:

Aug 5, 1988

Appl. No.:

7/228716

Inventors:

David W. Hart - Wilmington DE
Bohdan Dunas - Philadelphia PA
Joseph Krulikowski - Philadelphia PA

Assignee:

Special Projects Research Corporation - Wilmington DE

International Classification:

B63B 1500

US Classification:

114356

Abstract:

A method and device for controlling strain and deflection in a superstructure, resulting from movement/displacement of the main structure on maritime and aerospace vessels, and other structures which have significant strains and/or deflections induced by support displacements. This method involves the use of elastic devices inserted in the said superstructure and fine tuned with respect to stiffness, to an extent where the load distribution throughout the said superstructure can be controlled. The device is constructed by the use of material formed in a geometric shape which will allow yielding, to a desired amount of strain and/or deflections, in the elastic device, superstructure and main structure.

US Patent:

58424016, Dec 1, 1998

Filed:

Dec 13, 1996

Appl. No.:

8/764953

Inventors:

David K. Hart - Rosemont PA

Assignee:

David K. Hart Company - Rosemont PA

International Classification:

B26D 726
B26F 114

US Classification:

8369851

Abstract:

A punch assembly is provided for a rotary forms press, for punching holes in a sheet of paper or other material as the material travels between punch and die assemblies. The punch assembly is of the split ring type, and has a hub to be carried on a punch shaft and driven thereby. A split punch ring of multiple segments is provided, for mounting on the hub, with the segments being connected together. The punches are carried by the punch ring. There is a slip fit between the punch ring and the hub to allow movement between the punch ring and hub to accommodate minor repositioning of the punch ring and its punches as the punches enter holes of dies with which they will engage, with the slip fit allowing either rotary repositioning or axial repositioning. Clearance is provided to an enable a limited amount of axial repositioning.

US Patent:

52189198, Jun 15, 1993

Filed:

Feb 19, 1991

Appl. No.:

7/656791

Inventors:

Joseph W. Krulikowski - Philadelphia PA
Bohdan Dunas - Cinnaminson NJ
David W. Hart - Wilmington DE

Assignee:

Special Projects Research Corp. - Phila. PA

International Classification:

B03B 2512

US Classification:

114 74A

Abstract:

A method and device for constructing a auxiliary hull, exterior to the primary hull of a ship, which has the capacity to absorb impact energy preventing primary hull puncture, and can be easily retrofitted to existing ship hulls. This method and device involves the use of energy absorbing members arranged in a truss-like formation to support the auxiliary hull shell. The auxiliary hull shell can be laminated to weaken interlaminar shear strength and further increase energy absorption during impact and thus prevent auxiliary hull puncture. This method and device also allows for the void spaces created between the primary and auxiliary hull shells to be filled with material which will, distribute the impact forces to the primary hull over a wider primary hull area, serve to support the auxiliary hull shell under hydrostatic forces and provide additional buoyancy forces if the auxiliary hull shell is punctured.

US Patent:

59803975, Nov 9, 1999

Filed:

Apr 16, 1998

Appl. No.:

9/061138

Inventors:

David Welch Hart - Wilmington DE
Brian A. Barnabie - Laurel Springs NJ

International Classification:

A63B 6900

US Classification:

473437

Abstract:

A weighted device that attaches to a baseball or softball bat for the purpose of increasing the bat's mass during batting practice thereby increasing a persons strength and improving their bat control, ultimately improving their batting average and batting power. The device can be used during the actual practice of hitting a ball. The device can be attached to the bat at various locations along the tapered portion of the bat.