Patent Application
20060102071
The present invention relates to an apparatus and method for applying a foamed composition to a traveling substrate, and, more particularly, to a traveling substrate that has a tendency to be dimensionally unstable.
In the application of compositions to traveling substrates, it is common to generate a foam that carries the composition and to apply the foamed composition from an applicator nozzle across the width of a traveling substrate. As the foam disintegrates on and into the substrate, the bulk of the composition remains on or in the substrate without being washed or carried away, as is the case when compositions are applied in a liquid carrier by padding or emersion in a bath. Thus, the application of foamed compositions minimizes the waste of excess composition and the generation of hazardous or otherwise harmful waste water or other carrier waste.
An example of a foam application is the treatment of a traveling textile substrate with dye, size, softeners, resins and other agents.
Usually, when it is intended that the applied composition impregnate the substrate, the applicator applies the foam composition under pressure and at a location where the substrate is free or unsupported on the side of the substrate opposite the foam applicator. Substrates that are generally dimensionally stable, such as woven textiles, can be treated in this manner. However, substrates that have a tendency to be dimensionally unstable, such as knitted textiles, non-wovens, elastic fabric, and other somewhat uncontrollable substrates, have not been capable of having foamed compositions applied over an uncontrolled path of the substrate between supports because of the tendency of such substrates to contract widthwise and/or to have edges curl inwardly in the unsupported extent of the path of travel.
The present invention provides an apparatus and method that is capable of effectively applying a foamed composition to substrates that normally have a tendency to be dimensionally unstable and to do this efficiently and effectively.
Briefly described, the apparatus of the present invention includes a pair of closely spaced driven guide rollers over and between which the substrate is guided with sufficient roller engagement and controlled tension to minimize dimensional distortion. A foam applicator is provided with a substrate engaging foam dispensing nozzle face positioned within the space between the rollers of the pair of rollers to deflect the substrate inwardly between the rollers. The nozzle face extends in close proximity to the rollers to minimize the free extent of travel of the substrate between the rollers and the nozzle face. Thus, dimensional distortion of the substrate is minimized as it travels between the rollers and across the applicator face. In one form of the apparatus, the controlled tension is obtained by means for driving the rollers at controlled relative rates of rotation.
One of the guide rollers may be an input roller from which the substrate travels to the applicator nozzle face, and an infeed roller may be positioned closely adjacent the input roller, across which infeed roller the substrate travels onto the input roller, thereby minimizing the edge curling of the substrate. In one embodiment, the infeed roller forms a nip with the input roller through which the substrate travels to the input roller.
In a preferred form of the invention, the apparatus applies a foamed composition to a traveling substrate that is flat with first and second opposite surfaces and there are two pairs of guide rollers with the substrate being guided with one surface in contact with one of the pairs of rollers and the other surface being in contact with the other surface of the substrate. One applicator applies foam to one surface of the substrate between the rollers of one pair of rollers and another applicator applies foam to the other surface of the substrate between the rollers of the other pair of rollers. All of the rollers provide sufficient roller engagement of the substrate and are driven with controlled tension to minimize dimensional distortion.
Briefly described, the method of the present invention applies a foamed composition to a traveling substrate that has a tendency to be dimensionally unstable by arranging a pair of guide rollers in close proximity to each other, feeding the substrate for travel to and over a first roller of the pair and from the first roller to and over a second roller of the pair while maintaining sufficient roller engagement and controlled tension to minimize dimensional distortion. In practicing the method, a foam applicator having a substrate engaging foam dispensing nozzle face is positioned with the face within the space between the rollers to deflect the substrate inwardly between the rollers, while positioning the nozzle face in close proximity to the rollers to minimize the free extent of travel of the substrate between the rollers and the nozzle face, thereby minimizing dimensional distortion of the substrate as it travels between the rollers and across the applicator nozzle face.
The controlled tension may be obtained by the method of the present invention by driving the rollers at controlled relative rates of rotation, and disposing an infeed roller closely adjacent an input roller of the pair with the substrate being fed for travel between the infeed roller and the input roller and onto the input roller, thereby minimizing edge curling of the substrate. The infeed roller may be disposed to form a nip with the input roller and the substrate may be fed through the nip and onto the input roller.
In a preferred form of the method of the present invention the substrate is a flat substrate with first and second opposite surfaces and is fed for traveling with one surface over the rollers of the first pair of rollers and the other surface traveling over the rollers of a second pair of rollers. In traveling over the first set of rollers, the substrate is fed with the opposite surface engaging a first applicator nozzle face between and closely adjacent the rollers of the first pair and the opposite surface is engaged by a nozzle face of a second applicator disposed between the rollers of the second pair.
Preferably, the method includes driving the rollers of both pairs at controlled relative rates of rotation to maintain tension and to minimize dimensional distortion in the substrate as it travels over the rollers, between the rollers and across the applicator nozzle faces.
Further features, embodiments, and advantages of the present invention will become apparent from the following detailed description with reference to the drawings, wherein:
An outfeed roller 26, similar to the infeed roller 22, is positioned closely adjacent, and preferably forming a nip 28 with, the output roller 14. This outfeed roller 26 assures contact of the substrate S with the surface of the output roller 14, which is similarly covered or formed with a surface like that explained above with regard to the input roller 12, to assure travel of the substrate S with the surface of the output roller 14 without appreciable slippage.
A foam applicator 30 is disposed with a substrate engaging foam dispensing nozzle 32 having a face 34 positioned within the space 36 between the input and output rollers 12, 14. This substrate engaging foam dispensing nozzle face 36 extends sufficiently into the space 36 to deflect the substrate inwardly between the rollers 12, 14 to maintain contact with the substrate S for optimal application of foam under pressure from the nozzle face 34. The applicator 30 is adjustable in any conventional manner to obtain optimal deflection of and tension in the substrate S for optimum application of foam thereto. This tension also retains the substrate S in substantial dimensional stability. Maintenance of the substrate dimensionally stable is further enhanced by the nozzle face 36 extending in close proximity to the rollers 12 and 14, which minimizes the free extent of travel of the substrate between the rollers 12, 14 and nozzle face 34. This is illustrated more particularly in the enlargement illustration in
In
In the embodiment illustrated in
In operation, the substrate S travels from a preceding operation in substantially flat widthwise extent to the infeed roller 22, which maintains it substantially flat and guides it into the nip 28 with the input roller 12. The input roller 12 carries the substrate on its surface as the roller rotates to the space 36, in which the substrate S travels to the applicator nozzle face 34 through the short space 38 between the input roller 12 and the nozzle face 34. The substrate S then passes across the nozzle face 34, which applies the foamed composition under pressure to the substrate S with the nozzle face 34 deflecting the substrate S in the space 36 to maintain tension on the substrate S, which is unsupported on the surface opposite the surface on which the nozzle face 34 is applying foam so that the foam under pressure will penetrate fully into the substrate S.
The substrate S with the applied foam then travels from the nozzle face 34 through the short space 40 between the nozzle face 34 and the surface of the output roller 14, which then carries the substrate S on its surface to the nip 28 with the outfeed roller 26, from which the substrate S is discharged in substantially the same dimensional condition as it entered the apparatus. It then continues through further treatment, which may, for example, include a tenter frame for controlling the dimensional condition of the substrate S.
In an alternate embodiment illustrated in
With this arrangement, there is no outfeed roller 26 associated with the first pair of rollers 12, 14, but there is a second outfeed roller 66 similarly associated with the output roller 54 of the second pair of rollers. Otherwise, the second apparatus 50 is identical to the first apparatus 10 except that it is arranged oppositely for applying foam to the opposite surface of the substrate S.
Also, the operation of the second apparatus 50 is identical to the operation of the first apparatus 10, except for the application of the foam to the opposite side of the substrate S.
Further, the second pair of input and output rollers 52, 54 are driven by motors 68 and 70 controlled by the aforementioned controller 20, which is adjustable for optimum control of the relative rotation of all four guide rollers, 12, 14, 52 and 54 to obtain optimal stabilization of the dimensions of the substrate S as it passes through the first and second apparatus 10 and 50.
Another embodiment of the present invention is illustrated in
The substrate S is guided past the nozzles by two pairs of vertically spaced guide rollers. The first or upper pair of rollers, 112 and 114 are closely spaced in vertical alignment so that the nozzle 132 of the upper applicator 130 will be positioned in the space between the rollers, with the nozzle face 134 deflecting the substrate S and with the nozzle face 134 having its edges closely adjacent the upper rollers 112 and 114 to minimize possible dimensional distortion of the substrate S. This upper nozzle 132 applies the foamed composition to the first surface 156 of the substrate S.
The second pair of guide rollers 152 and 154 is below and vertically aligned with the upper pair 112, 114, with the upper, or input roller 152 of the second pair of guide rollers being below and closely adjacent the output or lower roller 114 of the upper pair of guide rollers. The substrate S is guided with the first surface 156 in contact with the rollers 112, 114 of the first pair to the opposite or second surface 158 of the substrate S being in engagement with the guide rollers 152, 154 of the second pair of guide rollers. This results in the first surface 156 of the substrate S being positioned for contact by the second applicator 60, with the nozzle face 162 of the second applicator nozzle 164 being disposed within the space between the guide rollers 152 and 154 of the second pair and with the edges of the applicator nozzle face 162 being closely adjacent the guide rollers 152 and 154 to minimize the free travel space for the substrate S, thereby minimizing the potential for dimensional instability of the substrate S.
Each of the guide rollers 112, 114, 152 and 154 of the two pairs of guide rollers are independently driven at controlled rotational speeds through individual motors and a controller in the same manner as described above with regard to the embodiment of
To guide the travel of the substrate S to the input roller 112 of the first pair of rollers and to provide sufficient extent of contact therewith for positive travel of the substrate S on the surface of the input guide roller 112, an infeed roller 112 is mounted above and to the side opposite the first applicator 130.
Similarly, an outfeed roller 166 is disposed below the output roller 154 of the second pair of rollers and to the side of that roller opposite the second applicator nozzle 164 for guiding of the substrate S from the output roller 154 of the second pair of guide rollers around the outfeed roller 166 from which the substrate S travels away from the apparatus 100.
In the embodiment of
To accommodate this pivoting of the applicators, 130 and 160, the pairs of guide rollers, 112, 114, 152 and 154 are mounted on pivotable brackets 102, 104. The upper pair of guide rollers 112, 114 and the infeed roller 122 are mounted on one bracket 102, which is an upper bracket. This upper bracket 102 is pivotally mounted on a rotatable shaft 106 that is pivotally secured to the frame 108 of the apparatus 100 above the upper pair of guide rollers 112, 114. This upper shaft 106 accommodates rotation of the upper bracket 102 in a conventional manner for pivoting the upper bracket and the guide rollers 112 and 114 and the infeed roller 122 mounted thereon sufficiently away from the upper applicator 130 to permit the aforementioned rotation of the applicator. When the applicator 130 is again positioned for applying foamed composition to the substrate S, the bracket 102 can be rotated reversely to reposition the upper bracket 102 and the guide rollers 112 and 114 of the upper pair of guide rollers and the infeed roller 122 for resumption of the application of the foamed composition to the substrate S from the upper applicator 130.
Similarly, the second or lower pair of rollers, 152 and 154 and the outfeed roller 166 are mounted on the lower bracket 104, which is mounted on a lower pivot shaft 109 disposed below the rollers for pivoting of the lower bracket 104 to move the lower or second pair of rollers 152, 154 away from the second applicator nozzle 164 to permit pivoting of the second applicator 160 into the flushing position of
To provide for the pivoting of the first and second applicators 130 and 160, each is mounted on a horizontal shaft 111 and 113 respectively. The applicators 130 and 160 and their respective shafts 111 and 113 are mounted to the frame 108. The applicators 130 and 160 are rotated in a conventional manner on the shafts 111 and 113 between the operating position indicated in
From the flushing position illustrated in
The foamed composition can be distributed to the applicator nozzles 132 and 164 in any desired manner. In the embodiment illustrated in
In operation of the embodiment illustrated in
When an application run has been completed, the applicators 130 and 160 are rotated on the shafts 111 and 113 to position the applicator nozzles 132 and 164 to extend vertically upwardly, as indicated in
Before resuming an applicating run, the applicators 130 and 160 are rotated to the draining position illustrated in
When the applicating run has been completed, the roller supporting brackets 102 and 104 are pivoted to move the rollers out of contact or interference with the applicator nozzles 132 and 164, the applicators 130 and 160 are rotated to the position illustrated in
In view of the aforesaid written description of the present invention, it will be readily understood by those persons skilled in the art that the present invention is susceptible of broad utility and application. Many embodiments and adaptations of the present invention other than those herein described, as well as many variations, modifications, and equivalent arrangements, will be apparent from or reasonably suggested by the present invention and the foregoing description thereof, without departing from the substance or scope of the present invention. Accordingly, while the present invention has been described herein in detail in relation to preferred embodiments, it is to be understood that this disclosure is only illustrative and exemplary of the present invention and is made merely for purposes of providing a full and enabling disclosure of the invention. The foregoing disclosure is not intended nor is to be construed to limit the present invention or otherwise to exclude any such other embodiments, adaptations, variations, modifications and equivalent arrangements, the present invention being limited only by the claims appended hereto and the equivalents thereof.
