Process and apparatus for air forming an article having a plurality of reinforced superimposed fibrous layers
View Patent ↗A process and apparatus for air forming an article having a plurality of superimposed reinforced fibrous layers. The layers are formed in substantially discrete forming chambers by depositing fibrous materials on a forming surface which moves along a forming path through the chambers. A first layer is air-formed on the forming surface as the surface moves through the first forming chamber and a second layer is air-formed over the first layer as the surface moves through the second forming chamber. A reinforcing web is embedded in the article during the air-forming process.
1. Apparatus for air forming a reinforced fibrous article having a plurality of layers, said apparatus comprising:
first and second substantially discrete forming chambers, each forming chamber having an entrance and exit,
a foraminous forming surface movable through said first and second forming chambers along a forming path length,
a first fiber inlet for introducing a fibrous material into said first forming chamber,
a second fiber inlet for introducing a fibrous material into said second forming chamber,
one or more vacuum sources in communication with said first and second forming chambers for drawing said fibrous material in said first forming chamber onto said forming surface to form a first layer on said forming surface and for drawing said fibrous material in said second forming chamber onto said forming surface to form a second layer on said forming surface over said first layer,
a source of reinforcing web located generally exterior to the first and second forming chambers,
a delivery mechanism for delivering reinforcing web from the source for application of the web toward the forming surface at a location along said forming path length.
2. Apparatus as set forth in claim 1 wherein said forming surface is on a drum rotatable to move the forming surface through said first and second forming chambers along an arcuate forming path length.
3. Apparatus as set forth in claim 2 wherein said location for application of the web is downstream of the exit of the first forming chamber.
4. Apparatus as set forth in claim 3 wherein said first and second forming chambers are separated from one another by a zone of separation along said forming path length, and wherein said location for application of the web is in said zone of separation.
5. Apparatus as set forth in claim 4 wherein said delivery mechanism comprises a rotatable guide roll mounted adjacent said forming path length for overlaying the reinforcing web on the first layer.
6. Apparatus as set forth in claim 2 wherein said delivery mechanism comprises a rotatable guide roll mounted adjacent said forming path length for overlaying the reinforcing web on fibers collected on said forming surface.
7. Apparatus as set forth in claim 2 wherein said location for application of the web is in the second forming chamber.
8. Apparatus as set forth in claim 7 wherein said delivery mechanism comprises a delivery tube having an open inlet end, a discharge end open to the interior of the second forming chamber, and a central passage extending between the inlet end and the discharge end, at least a portion of the delivery tube adjacent the discharge end thereof extending within the interior of the second forming chamber, said delivery tube being arranged for receiving the reinforcing web from the source of reinforcing web into the central passage of said tube at the inlet end thereof and guiding the web to the discharge end thereof for conveyance within the second forming chamber toward the forming surface.
9. Apparatus as set forth in claim 8 wherein the one or more vacuum sources are sufficient to draw the reinforcing web through the central passage of the delivery tube to the discharge end thereof and toward the forming surface.
10. Apparatus as set forth in claim 1 wherein said one or more vacuum sources comprises a first vacuum source associated with said first forming chamber and a second vacuum source associated with said second forming chamber.
11. Apparatus as set forth in claim 1 wherein said delivery mechanism is operable to apply the reinforcing web between the first and second layers.
12. Apparatus as set forth in claim 1 further comprising first and second fiber feed mechanisms for feeding fibrous materials into said first and second fiber inlets, respectively.
13. Apparatus as set forth in claim 1 further comprising a single fiber feed mechanism for feeding fibrous materials into said first and second fiber inlets, respectively.
14. Apparatus as set forth in claim 1 further comprising a first superabsorbent feed mechanism for introducing a superabsorbent material into said first forming chamber, and a second superabsorbent feed mechanism for introducing a superabsorbent material into said second forming chamber.
15. Apparatus as set forth in claim 14 wherein said first and second superabsorbent feed mechanisms are operable to introduce different superabsorbent materials into respective forming chambers.
16. A process of forming a reinforced fibrous article having a plurality of layers, said method comprising moving a foraminous forming surface through first and second substantially discrete forming chambers along a forming path length, each forming chamber having an entrance and exit,
introducing a fibrous material into said first forming chamber,
vacuum drawing said fibrous material in said first forming chamber onto said forming surface to form a first layer on said forming surface,
introducing a fibrous material into said second forming chamber,
vacuum drawing said fibrous material in said second forming chamber onto said forming surface to form a second layer on said forming surface superimposed on said first layer, and
overlaying a reinforcing web on fibers collected on said forming surface at a location along said forming path.
17. A process as set forth in claim 16 wherein said location is downstream from the exit of the first forming chamber.
18. A process as set forth in claim 17 wherein said first and second forming chambers are separated by a zone of separation, and wherein said overlaying step comprises overlaying said reinforcing web on said fibers in said zone of separation.
19. A process as set forth in claim 18 wherein said overlaying step comprises feeding the reinforcing web to a guide roll for overlaying of the web on said first layer.
20. A process as set forth in claim 17 wherein said location is inside the second forming chamber.
21. A process as set forth in claim 20 further comprising feeding the reinforcing web to a delivery tube for guiding of the web by the tube toward said forming surface.
22. A process as set forth in claim 16 further comprising introducing a superabsorbent material into said first forming chamber, and introducing a second superabsorbent material into said second forming chamber.