Method and apparatus for forming paperboard containers
AssigneeJames River-Norwalk, Inc.
InventorsAlbert D. Johns, Patrick H. Wnek, Ronald P. Marx
Life of this patent
Estimating the term…
Abstract
A method and apparatus for forming a container from a sheet of blank material, whereby a segmented male die member first forms the bottom and then the sidewall and rim of the container prior to the formation of the lip portion of the container while the blank is being restrained in a radial direction by the engagement of the blank by two opposing draw pad members.
Claims13
An apparatus for forming a blank of sheet material into a container, said apparatus comprising:
- (a) a die set including a female die being segmented and having bottom, lower radius, side wall, rim and downturned lip-forming surfaces generally defining the shape of said container;
- (b) draw pad means disposed to engage the outer peripheral edge of said blank placed in an initial plane during formation of said container for applying tension to said blank, said draw pad means including two opposite draw pad surfaces disposed to engage the opposite outer peripheral surfaces of said blank;
- (c) said die set further including a segmented male die member axially movable into mating relationship with said female die wherein said segments of said male die member engage said blank on the surface of said female die sequentially, said segmented male die member comprising:
- first forming means axially movable into mating relationship with said bottom and lower radius surfaces of said female die for forming said bottom and lower radius of said container;
- second forming means axially movable separately from said first forming means into mating relationship with said side wall surfaces and rim of said female die for forming the side wall and rim of said container;
- lip-forming means axially movable into mating relationship with said downturned lip-forming surface of said female die;
- (d) means for sequentially moving said first forming means and second forming means axially to form the bottom, lower radius, side wall and rim of said container prior to said lip-forming means engaging said blank;
- (e) first resilient means interconnecting said first and second forming means for allowing initial axial movement of said first and second forming means together, and for delaying application of forming pressure on said side wall surface until after application of forming pressure on said bottom and lower radius surfaces;
- and,
- (f) means for resiliently biasing said draw pad surfaces axially to engage said blank and maintain the peripheral edge of said blank in said initial plane during formation of the bottom, lower radius, side wall and rim of said container.
A method of forming a blank of sheet material into a container utilizing a sequentially engageable segmented female die including bottom, lower radius, side wall rim and downturned lip-forming surfaces and a segmented male die including a first forming means and a second forming means, wherein said container includes a bottom, a lower radius, a side wall, a rim and a lip, said method comprising the steps of:
- (a) holding the outer peripheral surface of said blank between two opposing surfaces such that said blank can retract radially upon application of a predetermined radial force on said blank;
- (b) engaging said first forming means with said bottom and lower radius surfaces to form the bottom and lower radius of said container while said outer peripheral surface is radially restrained;
- (c) engaging said second forming means with said side wall and rim surfaces to form the side wall and rim of said container subsequent to forming the bottom and lower radius of said container while said outer peripheral surface of said blank is radially restrained;
- and,
- (d) releasing radial restraint on said blank and thereafter forming said lip portion.
Dependencies are inferred from the claim text.