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:
Apr. 23, 1996
Filed:
Aug. 19, 1991
Applicant:
Inventor:
Bruce G Barton, Jr, Whitmore Lake, MI (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E04C / ;
U.S. Cl.
CPC ...
522208 ; 52503 ; 285363 ;
Abstract
A system for producing a sleeve-lined passage of uniform diameter D through a concrete wall molded in a concrete wall form including first and second form plates mounted in fixed relation and spaced by a wall width W includes a multiplicity of modular spools, preferably made of sheet steel; each spool comprises an annular shell having an axial length L less than W and an inside diameter D with front and rear flat flanges extending outwardly of the front and rear rims of the shell. For a first group of spools the axial length L is of three inches; for the other spools length L of four inches.