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:
Jul. 26, 1977
Filed:
Jan. 26, 1974
Applicant:
Inventor:
Theodore E Hillman, Cloquet, MN (US);
Assignee:
Conwed Corporation, St. Paul, MN (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B26F / ;
U.S. Cl.
CPC ...
83-1 ; 83-2 ; 83 98 ; 83101 ; 144 / ;
Abstract
A method and apparatus for perforating and, if desired, eroding fibrous board surfaces in a non-repetitive pattern are disclosed. The boards perforated according to the present invention are especially useful as acoustical tiles and panels. The board is formed and dried with a surface pattern developed on the board surface if desired and thereafter the board surface is punched by a series of randomly arranged pins or tacks on a plurality of rolls whereby a non-repetitive pattern results.