US 6,883,278 B2 · Muntin bars

Abstract

Method and apparatus for making a contoured muntin bar. A supply of sheet material having a finished surface on at least one side in the form of a coiled ribbon is unwound and fed along a strip path of travel to a punch station. At the punch station a ribbon punching mechanism punches the ribbon at a precisely predetermined locations along the ribbon to form one of a plurality notch patterns that define a portion of a contoured muntin bar. Downstream along the travel path from the punch station the ribbon is fed through a forming station having a succession of forming rolls that define a succession of forming roll nips to bend the ribbon and form a generally closed cross-sectional tube. The rolls form a number of bending stages to produce a muntin bar tube having a contoured shape with raised sides to provide an attractive appearance to a muntin grid.

Claims8

Dependent claims

A tubular muntin bar comprising:

a) an elongated tube having a mitred end and a flat end wherein the mitred end includes muntin bar portions adapted to fit over mid portions of other muntin bars to form a part of a grid and where the flat end forms an outer bound of a completed muntin bar grid for contacting a window spacer frame;
b) said elongated tube including side walls that have two relatively narrow top and bottom planar segments and two relatively wider side planar segments wherein the tube also includes a beveled transition portion between each side planar segment and either a top or a bottom planar segment and wherein one of the planar segments is formed by sheet portions of the tube that are bent to abut each other along a seam.

Dependencies are inferred from the claim text.

Muntin bars

Life of this patent

Muntin bars

Life of this patent

Abstract

Claims8