The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 21, 1991
Filed:
Apr. 21, 1989
Applicant:
Inventors:
Del E Walker, Lake Quivira, KS (US);
Stephen R Early, Olathe, KS (US);
Assignee:
Aera Transportation Products, Inc., Kansas City, MO (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
E06B / ;
U.S. Cl.
CPC ...
49501 ; 52829 ; 52630 ;
Abstract
A door for railroad boxcars has a balsa core sandwich construction in which a balsa core is sandwiched between thin fiberglass skins and reinforced at the perimeter by steel tubes to provide an economical and lightweight door that exhibits the requisite structural strength. The door has a concavo-convex configuration that prevents thermally induced warpage from deforming the door in a manner to cause significant interference in its opening and closing movement.