Apparatus for making hollow tubing having an annular wall of foamed material

Claim 2

In an apparatus for continuously forming hollow tubing of cured foam plastic material comprising a mandrel fixed at one end about which said tubing is formed by confining said foam material within an annular space of an envelope of flexible laminar material formed around said mandrel and allowing said foam material to expand, the envelope of confined foamed material being then moved longitudinally thereof and thereafter cured while moving along said mandrel, the improvement which comprises, means for aligning said mandrel by controlling its flexure to a position to provide a prOduct having the desired concentricity, and means associated with a region of said mandrel away from the fixed end for detecting variations in alignment from the desired alignment, whereby when a variation in alignment is detected, the means for aligning said mandrel is actuated to compensate for said variation.

Claim 3

In an apparatus for continuously forming hollow tubing of cured foam plastic material comprising a mandrel fixed at one end about which said tubing is formed by confining said foam material within an annular space of an envelope of flexible laminar material formed around said mandrel and allowing said foam material to expand, the envelope of confined foamed material being then moved longitudinally thereof and thereafter cured while moving along said mandrel, the improvement which comprises, wherein the mandrel is hollow and has air orifices in the surface thereof, means for feeding air into the hollow of said mandrel, means for aligning said mandrel by controlling its flexure to a position to provide a product having the desired concentricity, and means associated with a region of said mandrel away from the fixed end for detecting variations in alignment from the desired alignment, whereby when a variation in alignment is detected, the means for aligning said mandrel is actuated to compensate for said variation.

Claim 4

In an apparatus for continuously forming hollow tubing of cured foam plastic material comprising a mandrel fixed at one end about which said tubing is formed by confining said foam material within an annular space of an envelope of flexible laminar material formed around said mandrel and allowing said foam material to expand, the envelope of confined foamed material being then moved longitudinally thereof and thereafter cured while moving along said mandrel, the improvement which comprises, wherein the mandrel is hollow and has air orifices in the surface thereof, means for feeding air into the hollow of said mandrel, means for aligning said mandrel by controlling its flexure to a position to provide a product having the desired concentricity, and means associated with a region of said mandrel away from the fixed end for detecting variations in alignment from the desired alignment, whereby when a variation in alignment is detected, the means for aligning said mandrel is actuated to compensate for said variation.

Claim 5

In an apparatus for continuously forming hollow tubing of cured foam plastic material comprising a mandrel fixed at one end about which said tubing is formed by confining said foam material within an annular space of an envelope of flexible laminar material formed around said mandrel and allowing said foam material to expand, the envelope of confined foamed material being then moved longitudinally thereof and thereafter cured while moving along said mandrel, the improvement which comprises, wherein the mandrel is hollow and has air orifices in the surface thereof, means for feeding air into the hollow of said mandrel, means for feeding and for forming a first strip of flexible material into a tubular covering around said mandrel, means for feeding and for forming a second strip of flexible material into an envelope spaced from but completely surrounding said supported tubular covering and provide an annular space therebetween, means for inserting a curable foaming plastic mixture into said annular space, conforming mold means for supporting said envelope containing the foaming mixture within said annular space until the mixture has expanded and filled up the mold, means for aligning said mandrel by controlling its flexure to a position to provide a product having the desired concentricity, and means associated with a region of said mandrel away from the fixed end for detecting variations in alignment from the desired alignment, whereby when a variation in alignment is detected, the means for aligning said mandrel is actuated to compensate for said variation and provide a desirable product.

Claim 6

In an apparatus for continuously forming hollow tubing of cured foam plastic material comprising a mandrel fixed at one end about which said tubing is formed by confining said foam material within an annular space of an envelope of flexible laminar material formed around said mandrel and allowing said foam material to expand, the envelope of confined foamed material being then moved longitudinally thereof and thereafter cured while moving along said mandrel, the improvement which comprises, wherein the mandrel is hollow and has air orifices in the surface thereof, means for feeding air into the hollow of said mandrel, means for feeding and for forming a first strip of flexible material into a tubular covering around said mandrel, means for feeding and for forming a second strip of flexible material into an envelope spaced from but completely surrounding said supported tubular covering and provide an annular space therebetween, means for inserting a curable foaming plastic mixture into said annular space, conforming mold means for supporting said envelope containing the foaming mixture within said annular space until the mixture has expanded and filled up the mold, means for aligning said mandrel by controlling its flexure to a position to provide a product having the desired concentricity, and means associated with a region of said mandrel away from the fixed end for detecting variations in alignment from the desired alignment, whereby when a variation in alignment is detected, the means for aligning said mandrel is actuated to compensate for said variation and provide a desirable product.

Claim 7

The apparatus of claim 3, including guide means for inhibiting transverse drifting of at least one of said strips being fed to said mandrel, said guide means comprising means for sensing the drift of said strip transverse to said mandrel, means in force-applying relation to said strip for applying a transverse force to the strip in a direction opposite to the drift, and means coupled to the force-applying means and operable by said sensing means for actuating the force applying means when the sensing means senses the drift of said strip.

Claim 8

The apparatus of claim 4, wherein said guide means is provided for guiding each of said first strip and said second strip.

Claim 9

In an apparatus for continuously forming hollow tubing of cured foam plastic material comprising a mandrel fixed at one end about which said tubing is formed while confined within an annular space of an envelope of flexible laminar material formed around said mandrel and the confined foamed materiaL then moved longitudinally of said mandrel and thereafter cured while moving along said mandrel, the improvement which comprises, alignment means for aligning said mandrel to a position corresponding to a desired concentricity, means cooperably associated with said mandrel for detecting variations in said alignment, and means responsive to said detecting means for actuating said alignment means whereby to maintain said mandrel in a position corresponding to the desired concentricity of said tubing.

Claim 10

In an apparatus for continuously forming hollow tubing of cured foam plastic material comprising a mandrel fixed at one end about which said tubing is formed while confined within an annular space of an envelope of flexible laminar material formed around said mandrel and the confined foamed materiaL then moved longitudinally of said mandrel and thereafter cured while moving along said mandrel, the improvement which comprises, alignment means for aligning said mandrel to a position corresponding to a desired concentricity, means cooperably associated with said mandrel for detecting variations in said alignment, and means responsive to said detecting means for actuating said alignment means whereby to maintain said mandrel in a position corresponding to the desired concentricity of said tubing.

Claim 11

In an apparatus for continuously forming hollow tubing of cured foam plastic material comprising a mandrel fixed at one end about which said tubing is formed while confined within an annular space of an envelope of flexible laminar material formed around said mandrel and the confined foamed material then moved longitudinally of said mandrel and thereafter cured while moving along said mandrel, the improvement which comprises, wherein the mandrel is hollow and has air orifices in the surface thereof, means for feeding air into the hollow of said mandrel, alignment means for aligning said mandrel to a position corresponding to a desired concentricity, means associated with said mandrel for detecting variations in said alignment, and means responsive to said detecting means for actuating said alignment means whereby to maintain said mandrel in a position corresponding to the desired concentricity of said tubing.

Claim 12

In an apparatus for continuously forming hollow tubing of cured foam plastic material comprising a mandrel fixed at one end about which said tubing is formed while confined within an annular space of an envelope of flexible laminar material formed around said mandrel and the confined foamed material then moved longitudinally of said mandrel and thereafter cured while moving along said mandrel, the improvement which comprises, wherein the mandrel is hollow and has air orifices in the surface thereof, means for feeding air into the hollow of said mandrel, alignment means for aligning said mandrel to a position corresponding to a desired concentricity, means associated with said mandrel for detecting variations in said alignment, and means responsive to said detecting means for actuating said alignment means whereby to maintain said mandrel in a position corresponding to the desired concentricity of said tubing.

Claim 13

In an apparatus for continuously forming hollow tubing of cured foam plastic material comprising a mandrel fixed at one end about which said tubing is formed while confined within an annular space of an envelope of flexible laminar material formed around said mandrel and the confined foamed material then moved longitudinally of said mandrel and thereafter cured while moving along said mandrel, the improvement which comprises, wherein the mandrel is hollow and has air orifices in the surface thereof, means for feeding air into the hollow of said mandrel, means for forming a first strip of flexible material into a tubular covering around said mandrel, means for forming a second strip of flexible material into an envelope spaced from but completely surrounding said supported tubular covering and provide an annular space therebetween, means for inserting a curable foaming plastic mixture into said annular space, conforming mold means moveable along said mandrel for supporting said envelope containing the molding mixture within said annular space until the mixture has expanded and filled up the mold, alignment means for aligning said mandrel to a position corresponding to a desired concentricity, means associated with said mandrel for detecting variations in said alignment, and means responsive to said detecting means for actuating said alignment means whereby to maintain said mandrel in a position corresponding to the desired concentricity of said tubing.

Claim 14

In an apparatus for continuously forming hollow tubing of cured foam plastic material comprising a mandrel fixed at one end about which said tubing is formed while confined within an annular space of an envelope of flexible laminar material formed around said mandrel and the confined foamed material then moved longitudinally of said mandrel and thereafter cured while moving along said mandrel, the improvement which comprises, wherein the mandrel is hollow and has air orifices in the surface thereof, means for feeding air into the hollow of said mandrel, means for forming a first strip of flexible material into a tubular covering around said mandrel, means for forming a second strip of flexible material into an envelope spaced from but completely surrounding said supported tubular covering and provide an annular space therebetween, means for inserting a curable foaming plastic mixture into said annular space, conforming mold means moveable along said mandrel for supporting said envelope containing the molding mixture within said annular space until the mixture has expanded and filled up the mold, alignment means for aligning said mandrel to a position corresponding to a desired concentricity, means associated with said mandrel for detecting variations in said alignment, and means responsive to said detecting means for actuating said alignment means whereby to maintain said mandrel in a position corresponding to the desired concentricity of said tubing.

Claim 15

The apparatus of claim 8, including guide means for inhibiting transverse drifting of at least one of said strips being fed to said mandrel, said guide means comprising means for sensing the drift of said strip transverse to said mandrel, means in force-applying relation to said strip for applying a transverse force to the strip in a direction opposite to the drift, and means coupled to the force-applying means and operable by said sensing means for actuating the force-applying means when the sensing means senses the drift of said strip.

Claim 16

The apparatus of claim 9, wherein said guide means is provided for guiding each of said first strip and said second strip.

Claim 17

In an apparatus for producing elongated articles of cured foam material whose outer surface is formed of an envelope of flexible material which comprises, means for feeding a strip of flexible material along a longitudinal axis to an envelope-forming station, strip guide means located along said longitudinal axis for controlling the trAnsverse drifting of said strip fed to said envelope-forming station, including means for sensing the drift of said strip transverse to said axis, means in force-applying relation to said strip for controlling the transverse drift thereof, including means operable by said sensing means for actuating said force-applying means when transverse drifting of said strip is sensed, means for feeding a foaming mixture of curable material onto said strip, means at said envelope-forming station for forming said strip into an envelope about said longitudinal axis, thereby confining said foaming mixture within said envelope, and mold means following said forming station for confining said envelope of foaming material, the cross-sectional contour of said mold means corresponding to a desired peripheral contour of said elongated article and against which the foaming material expands.

Claim 18

In an apparatus for producing elongated articles of cured foam material whose outer surface is formed of an envelope of flexible material which comprises, means for feeding a strip of flexible material along a longitudinal axis to an envelope-forming station, strip guide means located along said longitudinal axis for controlling the trAnsverse drifting of said strip fed to said envelope-forming station, including means for sensing the drift of said strip transverse to said axis, means in force-applying relation to said strip for controlling the transverse drift thereof, including means operable by said sensing means for actuating said force-applying means when transverse drifting of said strip is sensed, means for feeding a foaming mixture of curable material onto said strip, means at said envelope-forming station for forming said strip into an envelope about said longitudinal axis, thereby confining said foaming mixture within said envelope, and mold means following said forming station for confining said envelope of foaming material, the cross-sectional contour of said mold means corresponding to a desired peripheral contour of said elongated article and against which the foaming material expands.

Claim 19

The apparatus of claim 11, wherein the mold means comprise movable upper and lower mold conveyors, each conveyor carrying a series of mold halves which mate with corresponding mold halves of the other, such that moving mating mold halves are adapted to confine said envelope of foaming material and move it along said longitudinal axis.

Claim 20

The apparatus of claim 12, including means for curing said envelope of foaming material while confined within said molds.