Claims
- 1. Apparatus for embossing a paper web or the like, comprising:
- frame structure;
- a plurality of angularly spaced apart support rollers supported for rotatable movement with respect to said frame structure about a common center with their axes of rotation substantially parallel, at least two of said support rollers comprising embossing rollers each provided with an embossing surface defining an embossing configuration forming a part of a composite embossing pattern and engageable with such web to emboss the same therewith;
- a platen roller floatingly confined by said support rollers with no rigidly fixed axis of rotation for rotatable movement with respect to said frame structure, said platen roller having both a cylindrical, essentially non-metallic, expansible and resilient backing wall component providing a backing surface disposed in facing juxtaposition with said embossing surfaces, and, in cooperation with the latter, being engageable with such web to emboss the same with a composite pattern comprised of each of said embossing configurations, and a gaseously-charged pressurizable chamber encompassed by said backing wall component to distend said backing wall component and urge said backing surface into intimate engagement with said embossing surfaces to form nips therewith, said backing wall component being depressible inwardly by said embossing rollers against the force exerted by the pressurized gas without significant outward bulging occurring in the backing wall component adjacent to said nips due to compression of said gaseous fluid in response to said depression, so that essentially no tensile force is imparted to the web passing through said nips as a consequence of velocity differences between the embossing and backing surfaces thereof; and
- means for rotatably driving said rollers.
- 2. The apparatus of claim 1 in which each of said embossing rollers is a substantially rigid unyielding component, at least one embossing roller having open generally linear elements of the composite embossing pattern provided along its web-engaging surface to obviate perimetric area clamping of such web when embossed by said linear elements.
- 3. The apparatus of claim 1 in which said platen roller further includes end wall components cooperative with said cylindrical backing wall component and defining said pressurizable chamber therewith.
- 4. The apparatus of claim 3 in which said platen roller is equipped with valve means communicating with said chamber to enable the gaseous pressure therewithin to be regulatively adjusted.
- 5. The apparatus of claim 1 in which all of said angularly spaced support rollers comprise embossing rollers each having a surface thereof disposed in facing juxtaposition with the backing surface of said platen roller and having an embossing configuration along its web-engaging surface engageable with such web to emboss the same as aforesaid, whereby the composite pattern embossed along such web includes configurations contributed thereto by each of said embossing rollers, and in which each of said embossing rollers is a substantially rigid unyielding component, at least one embossing roller having open generally linear elements of the composite embossing pattern provided along its web-engaging surface.
- 6. The apparatus of claim 1 in which the aforesaid driving means directly rotatably drives each of said embossing rollers.
- 7. The apparatus of claim 1 wherein at least one of said support rollers has a smooth non-embossing surface.
- 8. A method of progressively embossing a paper web or the like at a plurality of successive stations including embossing stations spaced apart along a predetermined arcuate path comprising the steps of:
- advancing such web along said arcuate path and through successive stations;
- maintaining the web in continuous, intimate and uniform engagement along one side thereof with an essentially non-metallic, cylindrical flexible support component defining the arcuate configuration of said path throughout the entire length of web extending at any time essentially through and between said successive stations;
- applying an embossing force at a plurality of said embossing stations by impressing the embossing surfaces of embossing rollers to the other side of said web which thereby exhibits a compressive force against said substantially cylindrical support component to deform the same in the vicinity of said plurality of embossing stations; and
- controlling the resultant deformation of said support component so that substantial deformation of said support component occurs only in the direction of said compressive force and no appreciable localized tensile forces are applied to such web due to such deformation tending to rupture the web due to the elongation thereof, said step of controlling the deformation of said support component comprising exerting a gaseous pressure force uniformly against the side thereof opposite said web enabling the support component to be displaced bodily thereagainst in response to the compressive force exerted thereagainst at each of said embossing stations, thereby obviating outward surface enlargement of said support along such web otherwise attributable to compressive deformation.
- 9. The method of claim 8 wherein said support component is a cylindrical platen roller having a substantially smooth outer surface and said stations are angularly spaced therealong; in which the step of applying an embossing force at said embossing stations includes the provision at each such embossing station of an embossing roller having an embossing surface forming a nip with said platen roller; and in which such web is continuously advanced along the arcuate path of travel defined by said support component through the nips formed at said successive stations.
- 10. Apparatus for embossing web material comprising:
- frame structure;
- a plurality of cylindrical support rollers mounted for rotation with respect to said frame structure at angularly spaced locations about a common center with their axes of rotation oriented in substantially parallel relation, at least one of said support rollers being an embossing roller having an embossing surface;
- an inflated platen roller floating confined by said support rollers with the axis of rotation of said platen roller being non-fixed and substantially parallel to the axes of rotation of said support rollers, said platen roller comprising an essentially non-metallic, cylindrically-shaped, resilient backing wall component having a substantially smooth outer backing surface and a hollow chamber containing a gas pressurized above atmospheric pressure in communication with said cylindrically-shaped, resilient backing wall component along the side thereof opposite said smooth outer backing surface and exerting an outward force on said backing wall component of sufficient magnitude to cause the backing wall component to assume a stretched condition having a greater diameter than when the platen roller is not inflated and said backing wall component is in a non-stretched condition, said backing wall component when in said stretched condition being in intimate engagement with the outer peripheral surfaces of at least three of said cylindrical support rollers to provide a plurality of nips between the support rollers and the platen roller spaced about the periphery of said backing wall component with the backing wall component flexing to accommodate any deformation occurring in said support rollers, the engagement between said at least one embossing surface and said backing surface displacing said backing wall component inwardly against said outwardly acting pressure force to minimize deformation of said backing wall component at the outer edges of the nip formed between said at least one embossing surface and the backing surface whereby substantially no velocity differential is created between the backing surface and said at least one embossing surface during rotation of said rollers and essentially no non-embossing tensile force is imparted to a web passing therebetween; and
- means for rotatably driving said rollers.
- 11. The apparatus of claim 10 wherein at least one of said support rollers has a substantially smooth peripheral surface.
- 12. The apparatus of claim 11 wherein a support roller having a substantially smooth peripheral surface occupies a predetermined position relative to said other support rollers whereby the web is adapted to pass through the nip formed between the platen roller and the support roller having a substantially smooth peripheral surface after passing through the nip formed between the platen roller and an embossing roller.
- 13. The apparatus of claim 11 wherein said support rollers comprise at least one background embossing roller, a roller having a substantially smooth peripheral surface and a spot embossing roller adapted to be contacted in seriatim by the web.
- 14. The apparatus of claim 12 wherein said driving means drives said support roller having a substantially smooth peripheral surface at a higher speed than it drives said embossing roller wherein said speed differential is in the range of about 6-8%.
- 15. The apparatus of claim 10 including means for maintaining said gas pressure in said platen roller hollow chamber in the range of about 20 to about 60 psig.
- 16. The apparatus of claim 10 wherein said resilient backing wall component has a hardness in the range of about 30 to about 60 durometer as measured at said smooth outer backing surface.
- 17. A method of embossing web material comprising the steps of:
- advancing the web material along a predetermined arcuate path through a plurality of successive work stations;
- maintaining the web in substantially continuous, intimate and uniform engagement along one side thereof with an essentially non-metallic, cylindrically-shaped resilient support component throughout the entire length of web extending at any time essentially through and between said successive stations;
- applying an embossing force at at least one of said stations to the other side of said web which thereby exhibits a compressive force against said support component to deform the same in the vicinity of the associated station; and
- controlling the resultant deformation of said support component so that substantial deformation of said support component occurs only in the direction of said compressive force and no appreciable localized tensile forces are applied to such web due to such deformation tending to rupture the same, said step of controlling the deformation including exerting a gaseous pressure greater in magnitude than atmospheric pressure against said resilient support component in opposition to said compressive force.
- 18. The method of claim 17 additionally comprising the step of napping the web by applying a substantially uniform tangential force to the surface of the web on said other side thereof at at least one of said stations.
- 19. A method of embossing web material comprising the steps of:
- disposing a plurality of work stations along a predetermined arcuate path;
- moving an essentially non-metallic resilient support member along said predetermined path;
- continuously exerting a gaseous pressure greater in magnitude than atmospheric pressure against said resilient support member along a first side thereof to stretch said resilient support member and continuously urge said stretched resilient support member against compressive forces exerted against the resilient support member at said plurality of work stations along a second side thereof in opposition to said first side, at least one of said compressive forces comprising an embosssing force;
- deforming said stretched resilient support member at said plurality of work stations through the application of said compressive forces;
- disposing web material in engagement with said resilient support member on said second side thereof;
- passing said web material through at least one work station whereat the compressive embossing force is applied to said web material at the side thereof not in engagement with said resilient support component so that said web material is embossed due to the cooperation of said compressive embossing force and the opposing force developed by said gaseous pressurized resilient support member; and
- controlling the resultant deformation of said resilient support member so that substantial deformation of said support member occurs only in the direction of said compressive force and no appreciable localized non-embossing tensile forces tending to stretch said web material are applied to said web material due to such deformation.
- 20. The method of claim 19 wherein said resilient member has a hardness in the range of about 30 to about 60 durometer as measured at said second side thereof.
- 21. The method of claim 19 wherein said gaseous pressure is in the range of about 20 to about 60 psig.
Parent Case Info
This application is a continuation in part of U.S. application Ser. No. 275,222, filed July 26, 1972, and now abandoned.
US Referenced Citations (6)
Continuations (1)
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Number |
Date |
Country |
Parent |
275222 |
Jul 1972 |
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