Method for making a laminated hook fastener
AssigneeVelcro Industries B.V.
InventorsWilliam J. Kennedy, George A. Provost, Gerald F. Rocha
Life of this patent
Estimating the term…
Abstract
A method for making an extruded hook fastener strip on a roll having hook forming cavities in its surface by extruding plastic material into the interface between the forming roll and a second strip carried by a backing roll is provided. The second strip is firmly bonded to the fastener strip on the side opposite the formed hooks.
Claims20
In the method for making plastic hooks utilizing an apparatus comprising a first cooled unitary forming roller having a plurality of hook forming cavities defined in the periphery thereof and extending inwardly therefrom;
- a second pressure roller positioned for coaction with said first forming roller;
- means for concurrently rotating said first and second rollers in opposite directions about their generally respective axis;
- means for forming an extrusion of molten plastic material adjacent said first and second rollers to be directed therebetween at an interface thereof such that said plastic material fills said hook forming cavities and forms a striplike member having a base portion and a great multiplicity of hooklike projections extending from one surface of said base portion and integral therewith;
- means for removing said striplike member from said first forming roller at a position spaced from the interface of said first and second rollers such that said hooklike projections are withdrawn from said hook forming cavities without opening said cavities after being cooled by said first forming roller to a desired temperature, the improvement comprising, introducing a sheet material having an interface surface and an exposed surface into said interface formed by said rollers so that said sheet material becomes an integral part of said striplike member on the side opposite said hooklike projections, said sheet material being introduced into said interface adjacent said second roller with sufficient tension to prevent said sheet material from interfering with the operation of the hook forming process, to form an insitu laminate with said striplike member, said exposed surface remaining substantially free of said plastic material.
In a method for making plastic hooks utilizing an apparatus comprising a first cooled unitary forming roller having a plurality of hook forming cavities defined in the periphery thereof and extending inwardly therefrom;
- a second pressure roller positioned for coaction with said first forming roller;
- means for concurrently rotating said first and second rollers in opposite directions about there generally respective axis;
- means for forming an extrusion of molten plastic material adjacent said first and second rollers to be directed therebetween at an interface thereof such that said plastic material fills said hook forming cavities and forms a striplike member having a base portion and a great multiplicity of hooklike projections extending from one surface of said base portion and integral therewith;
- means for removing said striplike member from said first forming roller at a position spaced from the interface of said first and second rollers such that said hooklike projections are withdrawn from said hook forming cavities without opening said cavities after being cooled by the first forming roller to a desired temperature, the improvement comprising passing sheet material having an exposed and an interface surface through web straightening means to assure said sheet material is properly centered relative to said backing pressure roller,
- impinging said sheet material onto securing means located around the periphery of said backing pressure roller, and
- introducing said sheet material into the interface between said first and second rollers while conveying said sheet material with proper alignment and in a smooth, undistorted fashion but sufficiently retaining said sheet material said backing pressure roll so that it is capable of withstanding the dynamic pressures created as said molten plastic flows and becomes an integral portion of said striplike fastening member on the side opposite from said hooklike projections to form an insitu laminate with said striplike member, said exposed surface remaining substantially free of said plastic material.
Dependencies are inferred from the claim text.