|국가/구분||United States(US) Patent 등록|
|미국특허분류(USC)||264/292; 264/219; 264/313; 264/324; 425/398; 425/399; 425/400|
|발명자 / 주소|
|출원인 / 주소|
|대리인 / 주소||
|인용정보||피인용 횟수 : 10 인용 특허 : 2|
Apparatus and method for forming curved needlepoint canvases from initially flat perforated sheet by applying pressure to a first side of the sheet, thus driving and deforming it into an aperture in a die, and by supporting the opposite side of the sheet during deformation with a pressure pad which includes a recess into which the deformed sheet is driven.
1. In an apparatus for cold drawing a generally flat perforated plastic sheet, the apparatus including a die having a bore therein terminating in an aperture, first means for holding said sheet adjacent said aperture, and a punch having a curved contact surface, said punch being movable from a start position spaced from said sheet to a first position pressing a portion of said sheet into said aperture and forming a depression in said sheet, the improvement in combination therewith comprising: a pressure pad having an end surface with a recess in t...