Patent Application
20080156417
The present invention relates to a method and equipment for the manufacturing of articles from web materials, such as textiles, non-wovens, films, or composites made there from. The articles have a three dimensional shape and/or comprise a belt or a hoop structure. In particular, it can be applied to the production of wearing apparel or garments, or of absorbent hygiene articles, such as disposable diapers.
The industrial manufacturing of articles such as garments having a three-dimensional (3D) shape or comprising a closed structure, such as a belt or a hoop, conventionally employs little automation, e.g. manual sewing of the components. Automated methods are rarely used, and are typically limited by complex designs and/or low production speeds. Such sewn articles are disclosed in EP-A-0988803, relating to a panty girdle, or US-A-2004/0098784, relating to a net pant, or WO-A-01/061093, relating to boxer shorts, however the manufacturing is not on production lines employing a continuous process.
In GB-A-2013326, the use of automated sewing machines in combination with a circular guide rail and an annular carrier to transport a pair of stocking material through several stations, such as seaming stations, is disclosed. Whilst this complex and heavy mechanical set up allows automated production, it is severely limited in production speed. US-B-04803935 discloses a method and an apparatus for forming belt loops and transferring the formed loop to a sewing station where the loop may be stitched to the waistband of a pair of trousers.
In WO-A-96/07376 absorbent pads are described, which are formed into a three dimensional shape by a thermoforming process. JP01284284A2 discloses a machine for continuous sewing of an annular resilient belt-form material. The machine inserts or sews a tubular elastic belt shape body, e.g. rubber ring, to tubular cloth, e.g. trousers or a skirt, continuously. The machine sews the cloth by guiding the rubber ring by a guide device having a guide plate, bending ends of tubular cloth to make a bent part, and placing endless rubber ring in the space made by the bent part and retreats to the open end side of the bent part. In US application US-A-2002/0084017, a process is described for the manufacturing of a 3D article, wherein waist elastic, an insert and a 3D skirt or trunk are combined by using an expandable/ retractable fixture, which is run through a process loop such as a loop conveyor system. This process and equipment however, is complex in design, and whilst the process may run automated, there are also severe limitations in the production speed.
Hence there remains the desire for manufacturing of complex articles at highly efficient production equipment.
A solution to this problem is provided by the present invention, which is a method for manufacturing shaped articles from one ore more web materials on a manufacturing equipment, wherein the articles form a closed hoop structure or a three-dimensional structure and have an inner and an outer surface, and are formed by connecting one or more regions of one or more web pieces of one or more web materials. The web materials are essentially flat by having a length dimension (x-direction) and a width dimension (y-direction) exceeding the thickness dimension (z-direction), thus having a first and a second surface along the x-y-direction. The web materials may form a sequence of web material pieces. The method is an essentially continuous manufacturing process, comprising at least one web treatment step acting on the inner and outer surfaces simultaneously by a web treatment unit comprising a web treatment head and a counteracting web treatment tool. The manufacturing equipment comprises a web path splitter means for parallel treatment of at least two web pieces in at least two web treatment sections, each of these sections comprising a treatment head of the web treatment unit and at least a first and a second web support means for temporarily holding and moving the web material pieces. Thereby, the second web support means is positioned z-directionally offset relative to the first web support means, thus forming a gap between the first and second web support means, wherein the gap distance between the first and the second web support means can be varied. The method comprises steps of
(a) feeding one or more pieces of web material via the web path splitter means to the web treatment sections;
(b) temporarily attaching a first region of a piece of a web material to the first web support means and a second region of the same or a different piece of a web material to the second web support means, such that the first and the second regions are positioned in the gap between the first and the second web support means;
(c) increasing the z-directional distance of the first and second web support means whilst the first and second regions of the web material(s) remain at least partly affixed to the respective web support means, so as to increase the gap distance between the web support means and the regions of the web material piece(s) affixed thereto,
(d) positioning the web treatment head in the gap to contact the surfaces of the web material regions oriented towards the web treatment head;
(e) positioning the web treatment head and the web treatment tool relative to each other and to the web material so as to allow them to interact each with one of the opposite surfaces of the web material(s);
(f) treating the first and the second web regions jointly by cooperatively operating the web treatment head and the web treatment tool of the treatment unit, thereby forming the structure of the article;
(g) removing the web treatment head from the gap and/or the article from the head;
(h) optionally further treating the article;
(i) removing the article from the web handling equipment.
The web materials may be made of films, textile, woven, or non-woven webs, or composites thereof. The first and second regions may belong to different webs; which may be of the same or different material type, orientation, or which may have undergone different pre-treatments. The webs material(s) may be pre-shaped webs, e.g. forming a closed structure like a belt or a hoop. The method may further include the use of other materials, such as pre-assembled pieces, bulk material, or fluids, and several process steps may be executed on one piece of web material. A preferred treatment step is the connecting of two regions, but further treatment steps may be included, such as cutting, pressing, or mechanically activating of webs.
The method is particularly suitable for the manufacture of shaped articles as garments for being worn on the lower torso, preferably as disposable garments or disposable absorbent articles. The articles may further comprise any or all of the following elements
(i) a hoop structure defining the waist opening of the article;
(ii) two hoop structures defining the leg openings of the article;
(iii) a centre piece connecting the front and rear regions through the crotch region of a wearer during use;
(iv) side panel materials positioned in the hip region of the wearer during use;
(v) the centre piece being connected to the leg hoops, preferably by a curved connecting line;
(vi) the side panels being connected to front and back parts of the centre piece, and either to the leg hoop, or to the waist hoop, or to both.
A particular embodiment of the invention relates to a method for handling a web material, which is an essentially continuous web or an essentially continuous sequence of pieces of an essentially continuous web, on a web handling equipment. The web handling equipment has an overall web path connecting a web supply means with a process section end point, whereby the web material comprises at least a first and second section being connected and spaced apart with the first section being oriented along the overall web path more towards the process section end point than the second section, wherein the method comprises the steps of
a) providing the web material on the web supply means;
b) moving the web material from the web supply means towards the process end section along the overall web path at an overall web path speed |v0| relative to the frame of the web handling equipment;
c) providing a web path splitting means positioned along the overall web path and comprising at least a first and a second web handling section, each of these web handling sections comprising a section frame, and at least one web support means connected to the section frame, having a surface which is movable relative to the section frame;
d) splitting the web path on the web path splitting means into at least a first and a second web sub-path, each running through one of the web handling sections; and transferring the web material along the web sub-paths to the web handling sections;
e) handling the web material in each of the web handling sections by affixing at least the first section of the web material to the surface of a web support means in the initial contact region of the web support means, without affixing the second section of the web material to the web support means surface; and by changing the speed of the surfaces of the web support means, while having at least the first section of the web material remaining affixed thereto, thereby changing the relative speed of the first section of the web material to a second section of the web material,
f) thereby transferring at least parts of the web material out of the initial contact regions of the web support means into an operating region of the web support means or of a further web support means, thereby forming a cross-directional fold in the web material;
g) performing at least a further web handling or treatment steps on the web material, preferably at least a step connecting two regions of one or two webs to each other;
h) moving the web material from the web handling section;
i) providing the web handling section for repeated executions of the web handling steps d) to h).
The present invention also relates to an apparatus for manufacturing shaped articles from one ore more web materials, the apparatus comprising
(i) a web path splitting means comprising at least two web treatment sections; preferably a rotatably mounted drum;
(ii) a web treatment unit, comprising at least two web treatment elements in the form of a web treatment head and a web treatment tool, which interact at least for the treatment of the web;
(iii) the web treatment sections comprising at least a first and a second web support means comprising moveable surfaces to which the web materials can be temporarily affixed, and an element of the web treatment unit, preferably a treatment head.
Therein, the web support means may comprise means to freely program the surface speed and direction, and the first and the second web support means may be arranged and comprise means to adjust their relative positioning, thereby forming a gap with a variable gap distance between them.
The web treatment head and the first and second web support means may also be arranged and comprise means to adjust their relative positioning to allow positioning of the treatment head in the gap.
In a particular embodiment, the web path splitting means is a drum, which is rotatable around its longitudinal axis, preferably comprising four, more preferably six, and most preferably eight web treatment sections. However, even higher numbers of treatment sections per web path splitting means, such as 30 or 60, may be employed.
The apparatus may comprise further web support means, and the web support means may comprise any or all of endless transport belts, at least one drive roll, a freely programmable drive motor, preferably a servo motor, non-contact power and data transfer to the drive roll, or vacuum suction means.
The web treatment head of the apparatus may comprise any or all of a means for affixing web materials, for repositioning the web materials, for repositioning the treatment head be this rotatably or translatorily, for expanding or reducing certain dimensions of the treatment head; for treating the web material in cooperation with the treatment tool, whereby at least one of the treatment means may allow connecting web material(s). The web treatment head may further comprise a moveable surface, preferably in the form of a transport belt comprising vacuum suction means and a freely programmable drive motor and a non-contact power and data transfer. One treatment head may interact with one or more treatment tools, and one treatment tool may interact with one or more treatment heads. The treatment tool may be affixed to the web treatment station, and be stationary or repositionable relative to the treatment head; or it may be affixed to the manufacturing apparatus, and thusly consecutively interact with consecutive treatment heads, as these pass by. The treatment elements may further comprise rolls, anvils, spraying, or cutting units. The apparatus may further comprise sensing devices and control means such as for the detecting and correcting position of web materials.
The apparatus is particularly suitable for the manufacture of shaped articles as garments for being worn on the lower torso, preferably as disposable garments or disposable absorbent articles. The shaped articles may comprise any or all of the following elements
(i) a hoop structure defining the waist opening of the article;
(ii) two hoop structures defining the leg openings of the article;
(iii) a centre piece connecting the front and rear regions through the crotch region of a wearer during use;
(iv) side panel materials positioned in the hip region of the wearer during use;
(v) the centre piece being connected to the leg hoops, preferably by a curved connecting line;
(vi) the side panels being connected to front and back parts of the centre piece, and either to the leg hoop, or to the waist hoop, or to both.
The same numerals in various figures refer to corresponding elements.
The present invention is concerned with a method of converting parts or pieces of a web material into shaped articles.
35 Generally, the term “web” relates to any material, which is essentially endless or continuous in one direction (generally denoted as “x-direction” or “machine direction” or MD). Webs are often, but not necessarily, stored, supplied, or used in roll form and thusly also sometimes denoted “roll goods”. Whilst these are then not “endless” in the strict sense of the word, their extension in this x-direction is significantly larger than in any other direction. By combining consecutive rolls or other batches, (“splicing”) such webs can be considered “endless” for all practical purposes. Webs may be transported in a “batch” form, such as when a roll thereof is shipped, or they may follow a “web path”, such as when the webs are unwound from a roll.
Often, but not necessarily, webs have along their x-directional length an essentially uniform thickness (herein denoted as “z-direction”), and/or constant width (herein denoted as “y-direction” or cross-machine direction or CD). Webs may be of essentially uniform composition, they can be mixtures of materials, they can be composites of materials such as being layered (different materials arranged in a juxtaposed position in the z-direction) and/or can comprise stripes of different materials or materials having different or varying properties (i.e. arranged in a juxtaposed position in the y-direction).
Thus, such web materials have two opposed surfaces extending in the x-y-direction of the web, and being spaced apart in the z-direction by the thickness of the web material. Within the context of the present description, the surfaces remain the first and second surface of the material, even if the material is cut into pieces, or turned, or bent, or inverted or otherwise treated. Hence, when a piece of a web material is folded once, the surface of two regions of the web material will be in contact with each other. This contact can be directly, or indirectly, such as when a further material is interposed between the two surfaces, such as a further web material. Typical examples for webs are—without implying any limitation—plastic films or foils, textiles, non-wovens, nets, scrims, paper, or cartons.
When essentially endless continuous web materials are converted to form discrete articles, they will at some point in time be cut or otherwise separated into an essentially continuous sequence of such web materials. When such continuous sequence is moved, it will form a “sequence path”, which may be considered as a web path. For example, if an essentially endless or continuous web, which is moved along a web path, is separated into pieces by repeatedly cutting off a certain length of the leading end of the web, the resulting sequence of cut pieces can still be considered a web material, following a web path, which is a continuation of the path which the continuous web followed before it was cut. As web materials in the form or parts or pieces follow the web path, they still have an orientation along this web path, which may be changed such as in case of rotating the web material or parts or pieces thereof. The sequence and the orientation along a web path distinguish web materials in the form of discrete parts or pieces from “sheets” for which neither a sequence nor an orientation along the web path can be defined. Thus, if the discrete parts or pieces of a web material are moved into a unit where they are stacked one upon the next to form a stack or staple, it would not be considered a web material, but rather a sheet, and the web path would end at the stacker.
Within the present context, the term “web regions” refers to topological regions of a piece of a web material, which are connected to each other and not separated or cut.
Web materials are often supplied in roll form, referred to when the width of the web defines essentially the width of the roll, or on spools, whereby the width of the spool is larger than the width of the web, and individual layers of the web are positioned adjacently albeit possibly overlapping in their y-dimension. Web materials may also be provided in boxes in a “festooned” arrangement, wherein one layer is folded onto the previous one, either in a single “accordion” arrangement or comprising a y-directional offset between individual layers.
Web materials need to satisfy certain requirements relating to their intended use, but they should further satisfy certain properties to allow or ease handling. Thus, webs should have a certain minimum integrity as well as bendability or flexibility, so as to allow handling. Webs may also need to satisfy certain properties to allow transportation thereof, such as certain minimum or maximum friction properties, porosities (i.e. resistance to fluids like gases when passing through), or electrostatic properties. Although any material does exhibit a certain inherent elasticity, webs are often referred to as “inelastic”, when they are not intended to return to essentially their original dimensions after being significantly extended.
A shaped article according to the present invention comprises at least one piece of a web material and has either a three dimensional (3D) shape or is forming a belt like or hoop structure. Typical examples may be garments, such as a pair of pants, or girdles, or panty hoses, but also disposable hygiene articles, such as baby diapers, training pants, adult incontinence articles and the like. Articles may be combined to form a combination article, such as when a disposable absorbent structure is inserted into a reusable garment, such as menstrual pants.
A first example for such an article is a belt-like structure 1000 formed of an elongated web, see
Also a simple pair of trousers 1000 may be formed out of a single piece of web material 1010, such as shown in
This design principle can also be applied to disposable absorbent articles in pant form as being worn around the lower torso of a wearer such as a baby or toddler, which are produced in a pre-closed state. As one alternative, these designs include an “overlap” arrangement of the front and rear parts, as schematically indicated in
For any such design alternative, the connection can be made permanent, such as by a line of adhesive, or by ultrasonic or pressure bonding, or it can be achieved by a re-closable “pre-closed” closure system. This refers to the fact that the article is shaped like a pant, and can be pulled up over the legs. When being worn, the closure system can be opened, such as for inspection by a caregiver, or for larger babies or toddlers when using a toilet.
The re-usable closure system may comprise re-fastenable adhesive tapes, mechanical fastener, or macro-fastener. Typically, the closure is achieved by positioning the front and rear ends of the unclosed article in an essentially flat state in close proximity to each other, and then to apply the connecting mechanisms. Often, an article comprises other elements, such as other (or secondary) web materials, strings, bands, or even other shaped elements.
Shaped articles can also be formed of two or more web materials, or pieces or panels thereof, which are attached to each other, as schematically shown in
The first piece 1210 of the article 1200 comprises a front region 1212, positioned in the front waist region of the wearer during use, a rear region 1218, positioned in the rear waist region of the wearer, and a centre region 1215 positioned in the crotch region of the wearer during use. In case of absorbent or hygiene articles, this piece of the article may comprise absorbent elements, and it may further be furnished with sealing components, such as leg elastics or leakage protection cuffs (not shown in the figures).
The two pieces may now be connected in the connecting regions 1201, such that the front and rear regions of the first piece 1210 are connected to the belt piece 1220 in the front and rear region thereof, respectively. In one embodiment as shown in the figures, a first (outer) surface 1028 of the first piece 1210 is connected in the front and in the rear to the second (inner) surface 1027 of the belt piece 1220, but it can be also that the inner surfaces 1026 are connected to the outer surfaces 1029 of the belt piece, or it may be different in the front and the rear. In yet an alternative design, the belt material may be a layered material, such as being folded along its x-directional axis, and then the first piece 1210 may be positioned between the two layers.
The front and rear regions may be connected in any conventional manner as known in the art, in particular with permanent or releasable connection systems. The first may be advantageous for non-disposable articles, or e.g. for disposable articles having a simple and inexpensive belt piece 1220. A releasable connection allows for designs with a re-usable belt piece, whilst the first piece may be disposable after each use.
This design may be modified to form “three hoop pants” or trousers, such as when a second, front part of the centre piece is added. Either this may be a separate piece of web material, and the two pieces are at least connected in the crotch region, or it may be an extension of the rear part of the centre piece extending through the crotch region into the front region, as shown in
The present invention shows particular benefits when being applied to more complex articles, in particular when these have a “three-dimensional” (3D) shape.
An article has a 3D shape, if the article comprises at least two connected regions, or pieces, or panels and if the article cannot be laid flat on one plane with all seams or connecting lines also lying flat on this plane, essentially without deforming the materials.
In contrast, the structures as shown in
A simple execution of a 3D article is schematically shown in
This can be pants 1000, having a waist opening along a waist line 1065, and two leg openings along leg cut outs 1040. At both sides, there are connecting lines in the two connecting regions 1030, thereby defining a front region 1012 and a rear region 1018 and a crotch region 1015 connecting these two. Thus, the waistline 1065 has two sections, a front waistline 1066, here shown shorter than the other, rear waist line 1067.
A further example of a simple 3D article is gored pantyhose 1400, as depicted in
Yet a further example for a shaped 3D article is a skirt like structure 1410, such as depicted in
A further exemplary 3D article is described in
Another shaped article is a pair of trousers or pants with a leg seal cuff. Typically, articles like pantyhose fit the wearer during use tightly around the legs but, due to the elastic properties, less tightly in the crotch region of the wearer. In
As shown in
A further embodiment of a baby diaper comprises leg extensions in addition to barrier leg cuffs, also well known in the art as such, as described in more detail in US-B-6926702. For such an article (see
An alternative design is a pair of pants with leg seal cuffs, as depicted in
The upper margin of the leg seal cuff 1629 is preferably executed in a curved shape, too.
As can be seen in
Such a leg seal cuff design provides particular benefits for articles, which require “acquisition space” (e.g. for diapers), tight but gentle sealing in the leg region (e.g. for feminine hygiene articles and especially menstrual pants), or gentle distribution of forces (e.g. for girdles), or provide a sustained dynamic fit for the wearer. There are various specific embodiments of this design principle, such as having certain regions of the article elasticized, e.g., the leg seal cuff may be elastically extensible in front-to-back direction only. Also, the side panels may be elasticized, optionally with a varying degree and/or directionality of elastication in different regions. The side panels may be openable, such as by combining a slit with a re-usable closure system, such as mechanical fastener. The side panels may also be composed of two sub-panels, e.g. first one made of a first material in the upper part (i.e. reaching into the waist region), and a second one made of a second material in the lower part (i.e. extending into the leg region).
A particular variant relates to a design, for which the leg seal cuff extends from the inner thigh region all around the leg, thereby forming a hoop as described for the three hoop pants (see
A particular execution of this variant is further depicted in
Any of the materials may be “breathable”, i.e. allowing air but not liquids to penetrate through. The centre piece may include absorbent material or it may be combined with an absorbent core. The leg seal cuffs may have a certain liquid or moisture absorbent capacity, which may be designed to capture liquid leaking from the centre piece absorbent structure, or which may be designed to absorb sweat.
Whilst the above examples illustrate important application areas for the present invention, there exists a plethora of other articles, which may be conveniently produced by applying the present invention, such as a shirt, blouse, jacket, coat, pyjama, corset, brassiere, girdle, or other protective and optionally disposable garments like surgical gowns, overall, masks, hats, gloves, sleeping bags, garlands, etc., including semi-finished items for any such articles.
As can be seen in the examples of shaped articles, such articles can be described by an “inner” (1026/1027) and “outer” (1028/1029) surface, as depicted in
Similarly, such articles can be described by a space, which is “inside” of the article, and the complementary space, which is outside of the article. The “inside space” is thus enclosed by the inner surfaces and—if these do not form a closed space—by one or more hypothetical cover(s) closing the space. Thus for a cylindrical tube, the cover will be represented by the circular areas at the front and rear edges. More generally, for 3D shaped articles of more complex shape, inside refers to the smallest space enclosed by the inner surface of the article and the smallest cover area required to close the space. Hence, for a pair of trousers, the inside space is formed by the inner surface of the article and the areas of the waist opening and the two leg openings. For any cup- or bowl-like shaped (or concave) article, the inner space will correspond to the volume of the bowl, whereby the surfaces will be complemented (if required) by the smallest closing areas. It should be noted, that the term “inside space” applies to the formed article, however, if one or more web materials are positioned so as to form an article, but are not necessarily connected yet (i.e. still forming unconnected pieces), this “preformed” arrangement is considered to have a corresponding inside space as just described.
The shaped articles as described above comprise web materials or regions thereof that are connected to other materials or regions. In the present context, “connected” refers to any physical or chemical connection between two pieces of material, or regions of one piece of material. Thus, it includes permanent attachment or bonding, such as welding, gluing, sewing, etc. Optionally such permanent attachments may have features to ease destructive tearing of the attachment, such as may be desirable for disposable pant-like absorbent articles. The connection can also be non-permanent, such as by using re-usable adhesive tapes, so-called mechanical fastening devices comprising connecting loop and hook structures, or so called macro-fastener, such a slot and tab designs, such as described in US-B-6669618. Typically, this re-usable attachment is closed during manufacturing, and the user may open it during use, such as when a caretaker applies or removes pant-like absorbent articles to or from babies or toddlers.
The present invention provides a simple and effective solution to producing shaped articles, such as belted, or “hooped”, or 3D articles, such as described hereinabove. The present invention applies the principles of web handling as laid out in detail in co-pending application PCT/IB05/000845. As shown in
The method comprises the steps of
a) providing a web material 100 on a web supply means 210;
b) moving the web material 100 from the web supply means 210 towards the process end section 900 along the overall web path 200 at an overall web path speed |v0| (208) relative to the frame of the web handling equipment;
c) providing a web path splitting means 300 positioned along the overall web path 200 and comprising at least a first and a second web handling section (301, . . . , 306), each of these web handling sections comprising a section frame and a web support means (330, 340, . . . ) connected to the section frame, having a surface which is movable relative to the section frame;
d) splitting the web path on the web path splitting means 300 into at least a first and a second web sub-path, each running through one of the web handling sections; and transferring the web material along the web sub-paths to the web handling sections;
e) handling the web material of the web handling sections by
e1) affixing the first region 112 of the web material to the surface of a first web support means 330 in the initial contact region 335 of the web support means without affixing a second region 118 of the web material thereto;
e2) changing the speed of the surfaces of the web support means 330, while having the first region of the web material remaining affixed thereto, thereby changing the relative speed of the first section 112 of the web material to a second section 118 of the web material;
f) thereby transferring at least parts of the web material out of the initial contact region 335 of the first web support means 330 into an operating region 336 of a web support means 330 or of a further web support means, and thereby forming a cross-directional fold in the web material;
g) performing one ore more web treatment steps on the web material by means of a web treatment unit, whereby at least one treatment step is the connecting of web materials;
h) removing the web material from the web handling section;
i) providing the web handling section for repeated executions of the web handling steps d) to h).
An apparatus to execute such a process comprises
i) a means for supplying (210) and for transferring (260, 270) the web material 100 towards a process section end point 900, thereby defining a web path 200 for transporting the web material at an overall web path speed 208;
ii) a web path splitting means 300 positioned between the web supply means 210 and the process section end point 900 for splitting the web path 200 into at least a first and a second web sub-path;
iii) the web path splitting means 300 comprising a web handling section (301, 302, . . . ) for each of the web sub-paths for handling the web material 100;
iv) each of the web handling sections (301, 302, . . . ) comprising a section frame and at least one web support means (330, 340, . . . ) connected to the frame, wherein the web support means has or have
a) a web support means surface for temporarily affixing a region of the web material to the web support means (330, . . . ),
b) an initial contact region (335, . . . ) and an operating region (336, . . . );
c) a web support drive means (333, . . . ) for changing the speed of the web support means surface of the web support means 330 relative to the frame of the web handling section, thereby moving at least a portion of the web material from the initial contact region 335 into the operating region 336, for creating a cross-directional fold of the web material;
v) and a web treatment unit comprising at least two web treatment elements, at least one treatment head 410 and a treatment tool 450 there shown to be affixed to a base outside of the rotating drum 300.
The web support means 330, . . . may be connected stationary relative to the treatment section frame, or may be movable, such as translatorily, such as indicated with arrow 357 for web support means 350, or rotationally, such a pivoting.
The web path splitting means may be a rotatably mounted drum 300. As shown for one exemplary web support means 330, this can have an essentially endless surface, preferably a belt 331, an electrical drive means 333, preferably an electrical servo motor, and a means for temporarily affixing the web material to the web support means, e.g. electrostatics, or mechanical fixation means, or preferably vacuum suction means 332. In a preferred embodiment, the web support means is a belt system, with an essentially endless belt, having a freely programmable electrical drive means integrated in a belt support roll, such as Smart Motors™ SM1720 R, such as available from Animatics, Santa Clara, Calif., USA, preferably employing non-contacting data and power supply such the CombiTrans system of Gauss, Salem, Germany. The apparatus may further be equipped with a helical screw feeder system adapted for receiving web material pieces for positioning of such pieces in a stack.
The web treatment unit of the present invention comprises at least two treatment elements, such as a treatment head 410 and a treatment tool 450. During the treatment step, the two elements are positioned on opposite sides of one or more layers of a web material. The web(s) are positioned on the treatment head 410 by at least a first and a second web support means 330, 350, which are arranged such that the distance 387 of the gap 385 between them can be varied, and the treatment head can be positioned in this gap 385 to treat the web.
Thus, the present invention allows the particular treatment of a web material. The term “treatment” refers to any physical or chemical interaction of a treatment unit with the web material, whereby the web material(s), or pieces or regions thereof are affixed to an element of the treatment unit.
For example, in order to connect two material pieces, these pieces must be appropriately positioned relative to each other, before they can be connected. Thus, the treatment unit has the function of positioning and connecting, such as by applying adhesive, or by thermal welding.
Within the context of the present invention, a “treatment head” is a treatment element, which can be positioned inside the article (respectively inside the web material which will form the article), whilst a “treatment tool” is the counter element to the treatment head.
For example, the treatment head may ensure appropriate positioning and supporting of the material whilst a treatment tool such as a heated embossing roll, operates on the “outside” (opposite surface) of the article. The treatment tool outside of the article may also be a counter pressure plate, whilst the treatment head moves the material against this plate.
The treatment unit may be a unitary piece of equipment having the two treatment elements connected via arms, one for each side of the web. The treatment unit can also comprise several essentially separated treatment elements cooperating appropriately for the treatment. The treatment unit can also comprise one treatment head on one side interacting with more than one treatment tools on the other side.
For the example of the web path splitting means being a rotating drum (or turret) with several treatment stations, each of these stations will have at least one treatment head. Each of these treatment heads may cooperate with a treatment tool affixed to the frame of the same treatment station. There may also be just one treatment tool affixed to the frame of the turret (i.e. it does not rotate when the turret does). As schematically depicted in
The interaction of the various elements is schematically shown in
The two main functions of the treatment unit are the accurate positioning of the web material(s) for the treatment, and the treatment itself. The positioning may be achieved by the treatment head alone or in cooperation with the treatment tool, whilst the treatment itself will always require interaction of the two elements.
The positioning may be achieved by means, which releasably affix the web thereto, such as by increased friction, or releasable adhesives or the like, or as a preferred embodiment, vacuum suction. In a preferred embodiment, the treatment head, i.e. the treatment element to be positioned in the web opening, will position the web accurately.
The positioning of the web by the treatment elements may be achieved by various movements, which the treatment element may undergo.
In a particular embodiment, the treatment head is equipped with moveable surfaces, such as shown in
The treatment head is similar to the one shown in
The belt systems may be driven by freely programmable drives, as described for the web support means hereinabove, or by other appropriate drive means. The belt systems may also have a vacuum suction system, as may be supplied by a vacuum source 460, delivered to the rotating drum by conventional means to a the web treatment section frame 399, and via a flexible tube system 462 to the lateral end of the treatment head, from where it may be further distributed to the transport belts 435. Optionally, the cover plates 425 may also be connected to the vacuum source, such that a web may also be affixed thereto. The cover plates and the transport belts may be connected by connection system 428, optionally designed so as to allow adjustment of the distance between the belt systems. The treatment head is affixed to the frame by a rotatable base ring 440, here shown with roller bearings 441. Further, the treatment head comprises a reciprocating piston system 445, here indicated by three tube- or rod-like elements 447 and roller bearings 446. The piston system may be driven by freely programmable linear motor drives 448, a cam based drive system, or a vacuum and positive pressure based system, or other appropriate means. Whilst the treatment head is shown affixed to one side of the frame, it may also be affixed on the opposite side thereof, or in any other manner allowing to move into the gap between the first and the second web support means.
Apart from the positioning and optionally re-positioning of one or more webs pieces or regions, the treatment unit will have special means to interact with the web.
A simple interaction may be the folding of a region of a web along a longitudinally oriented folding line by means of a folding plough, such as when lateral side regions of a web either extend beyond the side margins of a web support means, or are released from a web support means, such that these can be folded along a longitudinal fold line. Such a folding plough can be mounted stationary on the equipment frame or on the section frame. Typical other interactions may be connecting by gluing, welding, compressing. etc. It may also include the attaching of connections means like buttons or macro fastener. Another typical interaction may be the cutting of webs, such as by rotating knives, laser beams, etc. A particular interaction relates to the ability of the treatment head to change its size, respectively its circumference, as described hereinabove. This can for example be used to receive an elasticized web in an non-expanded state, but to further treat it in a stretched state, e.g. bond it in stretched state against another web such that the combined web will contract when released. In case the circumference of the head is controlled by respective control means acting in cooperation with appropriate sensing devices, this circumference variability can be used to precisely position different materials relative to each other. Also, several treatment steps may be executed in parallel or consecutively by one treatment unit.
During the treatment (other than potentially the positioning or repositioning), the treatment elements of the treatment unit will cooperate, with one on each side of the web. Cooperating can mean, that one element functions as (counter-) support whilst the other acts on the web, such as by pressing, or spraying, embossing, etc. Both elements may have intermeshing tools, e.g. rolls, such that the web between these rolls is stretched (see above mentioned US-B-5143679). One or both of the elements may provide temperature changes (heating/cooling), changes in position in x- and y-direction thereby creating a specific glue pattern while passing by a stationary glue head.
The web support means need to position the web materials or articles accurately relative to the treatment head, and the article must be “opened” so as to allow the treatment head to be positioned “inside” the article. To this end, at least one of the first or second web support means is moveable relative to the other so as to “open” the inner space of the article (or the web materials or pieces thereof which are about to form the article during the process).
In the case of the web path splitting means being a rotating drum with web treatment sections as segments thereof and web support means being connected to the mounting frame of the web treatment section segments, the second web support means may move “up and down”, which typically will be relative to the x-direction of the web material, or inwardly/outwardly relative to the frame of the rotating drum. The inner space may also be opened by pivoting the web support means appropriately (typically around an axis parallel to the y-direction of the web, and hence of the web support means).
Once the inner space of the article is accessible to the treatment head, the head will be re-positioned into this space. This can be achieved by any relative movement of one or more web support means and the treatment head along any three-dimensional path, such as translatory movement along a straight, curve-linear, or a circular path. It may include rotational movement, or pivoting around any axis. Thus, the treatment head may laterally be moved into this space, such as may be achieved by a piston/mandrel design. Alternatively, the first and second web support means may be transversely moved along the x-direction of the web. The treatment head may be introduced by a rotational move, or the relative movement of treatment head and web support means may be achieved by combining any of these movements.
For the application of the present invention to articles comprising two parallel hoops connected to a centre piece, a loop forming tool attached to the front face of a treatment head may support appropriate unfolding of the hoops into the correct 3D shape. Whilst such a hoop forming tool may be applied with various treatment head executions, its functioning is explained in further detail in the context of example D.
A further optional feature which is particularly suitable for articles comprising a centre piece material exhibiting a varying width and leg hoops, such as when ears are extending laterally outwardly of a continuous web material. Due to the overlapping of ear material with parts of the leg hoop material or centre piece material upon creation of the 3D shape on the forming head, this part of the material may not be accessible for being appropriately bonded. Thus, a part of these ears may be folded over prior to transferring the web to the web path splitting means. This upstream process step can be performed on a ear flipping drum, which may be combined with various embodiments of the present invention, but is for simplicity described in the context of a specific example (Example E).
The present invention is particularly useful for automated high speed production lines. In the present context, high speed refers to overall web paths speeds of 5 m/sec or more.
The present invention is further explained by describing specific process steps and the corresponding equipment set up for particular embodiments. This should, however not be seen in any way limiting, but the skilled person will readily see further variations as well as applications.
The present invention provides a simple and reliable alternative to produce disposable absorbent articles of the “pant type” with an overlap side seam, such as described in the above, and shown in
Typically, several web materials and other materials, such as forming the absorbent core, are added to one web material, in
When the cut web piece is fully drawn into the gap 385, the gap width 387 is increased, such as by moving the second web support means radially inwardly towards the centre of the drum. Whilst the first (1012) and second (1018) regions remain firmly attached to the respective web support means 330 and 350, the attachment of the centre region 1015 is somewhat loosened to compensate for the increased gap width. Thus, the web piece shows the rough shape of the article (see
When the gap width has reached the predetermined distance 387′, a web treatment head 410 is positioned into the opening, such as transversely moving the treatment head, and parts of the web which extend laterally outwardly from the web support means 330 and 350 may be pushed against the treatment head, such as by four guide plates 490, i.e. one for each lateral sides both of the front and rear regions of the web. The guide plates may be arranged movable relative to the web treatment section, or—as indicated in
The guide means such as the guide plates 490 will bend and guide the lateral side portions of the first (1012) and second (1018) region of the web material such that they lie in an overlapping arrangement on the treatment head, which may comprise suitable attachment means 463, such as vacuum suction regions, so as to maintain this relative positioning of the regions. Further, the treatment head may comprise elements to treat the material, such as glue or pressure bonding means, which are appropriately positioned to correspond to the regions of the article, which are to be treated, such as being connected to each other.
Now a treatment tool 450, e.g. an embossing tool, is positioned appropriately relative to the treatment head, and the treatment head and the treatment tool cooperate so as to create the connection. The connecting system may also be re-closable, such as when hook loop or re-usable tape systems are applied.
A further article, which can advantageously be produced by applying the present invention is a “belted pant article” as schematically depicted in
The process steps are schematically depicted in
The second material which will form the belt piece 1220 may be delivered as a single layer or a composite web having a web width (y-direction) corresponding to the (non extended) waist circumference. Preferably, it comprises elastic material, and may be extendible in its y-direction, such as by being activated by a set of intermeshing rolls, as described in US-B-5143679. This web is then folded longitudinally, such that the laterally outwardly regions having a width extension of about a quarter of the total width, are folded such that they lay on the centre half region of the web, optionally with a certain overlap so as to ease connecting the outer transversal edges. Optionally, the side edges may already be connected at this point in the process. Alternatively, two webs may be superimposed and their ends bonded together, giving a closed belt with butt type closure on the sides. In yet another embodiment, a wide first web may be folded on both sides such that a gap remains, which is overlaid with a narrow second web. The connection between the first and second web may be by glue, or mechanical fastener, or macro fastener, or heat bonding, or a combination thereof. The thus folded and closed web 104 (see
As next step, the gap distance 387 of the gap 385 is increased. This gap distance increase may be achieved by pivoting the web support means 350 closer to the centre of the rotating drum, as indicated in
The treatment head 410 can now be moved into the opened belt structure (see
In the meantime, a continuous first web material 102, which may already be prepared so as to form the centre piece 1210 of the article after being cut, is also transferred to the same drum to which the belt piece web material is fed, however angularly offset to the transfer point of web 104, here shown to enter in the region of the neighbouring web treatment section. Thus, the centre piece material 102 may be appropriately cut by a second cutting unit 397, and transferred to web support means 330 and 340. Initially, both web support means 330 and 340 may be positioned leveled and run idle, i.e. the circumferential speed 308 of the turret corresponds to the speed of the incoming web, or they run at equal speed, so as to allow transfer of the web material being fed in slower or faster speed relative to the circumferential speed of the turret in a flat state (see
As next step, the gap distance 387 of the gap 385 is increased, whilst the front (1012) and rear (1018) regions are held affixed, and centre region 1015 next to the CD fold is somewhat released, so as to compensate for this distance without imparting undue strain in the article. This gap distance increase may be achieved by pivoting the web support means 350 closer to the centre of the rotating drum, as indicated in
Now, the centre piece can be transferred to the treatment head, here shown by the head moving transversely into the gap, whilst the belt piece material 104 remains “parked” e.g. on the waist hoop holding pins.
Once the treatment head is outside of the gap 385, but before it is fully retracted, it may rotate 90° around its longitudinal axis 412. As the turret is continuing to rotate, it passes by treatment tool 450 (in
The treatment head may rotate to its original position and move again into the gap 385, from where the combined belted product may be removed, e.g. by being transferred into a screw feeder running parallel to a tangent of the rotating wheel.
Instead of or in addition to the glue application, the treatment tool 450 may comprise other bonding means, such as for heat, pressure or ultrasonic bonding. Alternatively, the connection can be achieved by releasable adhesive or mechanical closure, or by other connecting means like macro fastener, well known to the person skilled in the art.
A particular benefit of the present invention is, that is allows the manufacturing of 3D-articles. A 3D article, as depicted in
A further application of the present invention may produce articles in the form of pants having three hoop or belt-like structures encircling the waist and the legs, as described hereinabove, and in
The first steps of providing the waist hoop material and transferring it onto the waist hoop holding pins are identical to example B, which correspond to
The centre piece 102 is shown in
The web 102 is delivered to the wheel via a guide means 1927. The wheel 1910 comprises recessed areas 1920 corresponding to the web regions which are not intended to be flipped over. The other regions 1930 are positioned on elevated shims. Vacuum holes 1940 just aside the shim in the recessed area forces regions 1943 on the shims to turn by 90° into the vertical (see
Also this combination can be performed before it is fed to the rotating drum by a conventional “cut and slip” process, as well known the person skilled in the art. The material for each leg hoop is supplied analogously to the waist hoop material in example B. As shown in
The treatment head is equipped at its front side with a leg hoop forming device 470, as further schematically depicted in
The loop forming tool comprises for each leg e.g. two semi-elliptic butterfly baffle rings 472, connected to the front face of the treatment head so as to allow them to lay flat on this front face (as shown in the left portion of
When this treatment head is moved into the opening of the web towards web handling section frame 399′, guide ploughs 473 fold the side pieces towards the sides of the treatment head (as described in the context of Example A). Because of the attachment of the seal cuff material to the centre pieces, it will open into a hoop structure, which is supported by the loop forming tool, which are “opening” the butterfly wings 472 from the vertical position to an essentially flat position, further supported by the projections.
Then, a T-shaped connecting line on each side of the article can be formed by passing the head by a treatment tool acting from the outside against the article, while the treatment head provides the necessary backpressure from the inside of the article. The so formed T-shaped bonding line connects the lateral sides of the side pieces to each other and to the leg seal cuff. This forming of the connection line is eased by the ear flipping process as described in the above.
The treatment head may now retract towards its base. The centre piece may now be combined with the waist hoop (see
Prior to collapsing the article for discharge and packing. the structure has a true 3D shape (i.e. it cannot be laid flat on a plane with all connecting lines being flat, too). Thus, there may be a certain amount of deformation when the article is removed from the treatment head, and further processed towards packaging. However, when being used, the structure will appropriately open to the body shape adapted 3D form.
The method relates to the malting of an article comprising leg seal cuffs extending from the crotch area downwardly along the thigh, as shown in
In a first, conventional combining step, which may be executed upstream of the web path splitting means, a first material, which will form the centre piece 1610 of the article, and two further materials, which will from the left and right leg seal cuff, respectively, are provided. In a cut and slip unit, the leg seal cuff materials are cut to their appropriate length, and spaced apart in their x-direction at a distance corresponding to the size of the article (see also
The first web material and the leg seal cuff materials are now connected, such as by a glue line, which may be applied before the webs are combined, or by pressure or ultrasonic bonding. Preferably, the bonding line is curve-linear so as to form the upper edge 1629 of the leg seal cuff. This combined web is now transferred to a web path splitting means, and—analogous to the previous examples—onto a treatment head, which may be of the design as depicted in
In a first process option, the treatment head is now moved out of the gap between the web support means, and rotated by 90° around its longitudinal axis 412. In the meantime, two unconnected side panel material layers may already have been fed to the drum and into the gap 385, such that each of these can now be affixed to one of the web support means. The treatment head may now move into the widened gap again, and pick up these two pieces of material on the two opposed surfaces, which are not covered, by the first material. The treatment head may comprise beveled edges and the respective neighbouring materials may overlap in these beveled regions, such that the treatment head may rotate appropriately and interact with treatment tools so as to bond the side pieces to the centre piece and the leg seal piece.
A second process option allows an even more compact design of the overall equipment, as depicted in
In addition to the equipment design advantages, this process option offers significant freedom for product design variants, with regard to the combination of materials or material properties. For example, the side panel pieces 1624, which corresponds to the waist region in the combined article may have higher or lower elastic contraction forces than the region 1623, or different orientation of the elasticity.
This example relates to the manufacturing of products having a leg seal cuff design combined with leg hoops, as depicted in
A first web material is provided, which will form the centre piece 1610 of the article, lying on the garment side of the article, i.e. being oriented away from the wearer during use. A second material is provided, which will form the side pieces or side panels 1620. The first and second materials are connected by conventional means, such as a well known “cut and slip” unit, such cut pieces of the second material are attached laterally outwards to the first material so as to form “ear extensions” 1620 as depicted in
Two further pairs of a further double layer material are provided which will form the leg seal cuffs 1630 in the article. The double layering may be achieved by providing two layers of material. The double layer materials are cut to a length corresponding to half of the leg encircling circumference, and bonded at their front and trailing edges to each other. Optionally, one material having the cut length corresponding to the full circumference of the leg may be folded back onto itself, bonded, and cut transversely.
The thusly cut, bonded pieces are spaced apart in their x-direction, at a distance to fit between the spaced apart side pieces. Via conventional guide means, the pieces are positioned on the first web material, at a position corresponding to the crotch region, and partly overlying the first web 1610 but extending laterally outwardly the longitudinally extending lateral side margins of the web 1610.
The first web material and the lower layer of the leg seal cuff material (i.e. the one in direct contact with the first web) are now bonded, such as by activating a glue line, which may be applied to the first web prior to the combination. Preferably, this bonding line 1625 has a curve-linear shape. Optionally, the lateral outward margins 1629 of the leg seal cuff materials may be cut curve-linearly.
These two materials are cut and combined by conventional technique, such as by “cut and slip” units, both with their x- or machine direction aligned, and adhesively bonded, so as to create a continuous web formed by the centre piece material 1610 with leg seal cuffs attached thereto.
Similar to the process as described for the “belted pant” (example B), the continuous web 1610 with side pieces and double layer leg seal cuff connected thereto is fed to a web path splitting means and into the gap between the two web support means 330 and 350. Upon opening of the gap 385, the front region 1612 of the then cut piece 1610 with the front side regions attached thereto will be attached to the first web support means 330, and the rear region 1618 will be attached to the second web support means 350. The centre region 1615 with the dual layer leg cuff materials attached thereto spans across the gap 385. Thus, at this moment, the web piece 1610 is still an essentially flat structure in a lying open U-form arrangement.
The treatment head corresponds in design to the treatment head 410 as shown in
Then, a T-shaped connecting line on each side of the article is formed by passing the head by a treatment tool acting from the outside against the article, while the treatment head provides the necessary backpressure from the inside of the article. The so formed T-shaped bonding line connects the lateral sides of the side pieces to each other and to the leg seal cuff. Then, the treatment head moves out of the gap again, and the article is collapsed prior to being discharged.
Prior to collapsing the article for discharge and packing, the structure has a true 3D shape (i.e. it cannot be laid flat on a plane with all connecting lines being flat, too). Thus, there may be a certain amount of deformation when the article is removed from the treatment head, and further processed towards packaging. However, when being used, the structure will appropriately open to the body shape adapted 3D form.
This example builds on example F and aims at producing an absorbent article, such as a diaper, having a leg hoop design in combination with a secondary topsheet 1712, as schematically shown in
In a further modification of the process as described in examples E and F, the leg hoops or leg cuffs are not connected to the outwardly laying material of the article, but rather onto the wearer oriented (“topsheet” side), refer to
Whilst the above examples focused on articles, for which a “main” orientation of the article follows the MD-orientation of the respective centre pieces, the same principles can be applied to a manufacturing process, where the main orientation of the article (e.g. following the line from front to back through the crotch region of the wearer), is aligned with the crotch direction of the web material.
The overall process 900 comprises a first group (910) of process steps relating to providing raw materials, a second group (940) of process steps relating to pre-combing raw materials or intermediate structures to intermediate structures, a third group of process steps (960) relating to the combining of the article, and the final process step 990 of packing the article.
In a first group, the leg hoop material 913 and the leg extension/crotch barrier material 915 are provided in roll form, and fed into a first pre-combining step 941 forming the leg hoop and crotch barrier composite. The resulting composite is combined in a conventional “cut and slip” unit 945 with the backsheet material 917, optionally pre-combined in a pre-combining step 943 with a sidepanel material 919.
In a parallel process path the absorbent core and topsheet related items are combined. In a preferred execution, the core is so called “roll-stock” material, i.e. the absorbent materials such as superabsorbent material, and/or fibrous material as well as binding material are forming a continuous web 921, optionally with an envelop material such as a tissue or a non-woven, as may be supplied on a roll or a spool. Alternatively (not shown), the core can be made according to any other core forming process, such as, but not limited to laying down a mixture of e.g. cellulosic fluff and superabsorbent material and glue, and enveloping this in a carrier, such as a tissue or non-woven material.
A further material is the topsheet 923, overlying the article on the wearer side. Typically, this is a non-woven material, supplied on rolls. Many articles comprise barrier leg cuffs, which are relatively narrow strips of non-woven material 925, which may be combined with a thin barrier cuff elastic 927, which are designed to fit into the crotch crease of the wearer during use. Whilst such features are compatible with the present invention, it is believed that the design elements as described herein make barrier cuffs unnecessary, as the sealing and containment performance is already significantly enhanced.
The two intermediate structures leaving the combination station 945 and 949 are further combined in station 947, which still can be conventional web handling.
In a third path, the waist roll stock material 931 and the closure system elements, here shown as a mechanical fastening system comprising hooks 933 and loops 935 are connected in a combining step 950 to the waist belt combination. Optionally, this composite may be folded, as depicted by unit 955.
Thus, the composites leaving the units 947 and 955 may now be transferred to the so called “pant combiner” 960, which may be rotating drum or turret as an example for the web path splitting means, and thus represent typical webs as may be suitably employed in the above described process. Upon appropriate cutting (963 and 965), turning, and opening, and combining (967), the final article may be transferred to the packing unit 990
In contrast to conventional combining steps, the pant combiner is not necessarily the speed limiting factor, as the web path splitting means principle allows the decoupling of the process treatment times from the overall process speed. Henceforth, the present process not only provides automated production capabilities for hitherto not known product designs, but also provides for a multitude of known product designs an efficient production alternative.
| Number | Date | Country | Kind |
|---|---|---|---|
| PCT/IB2005/000845 | Mar 2005 | IB | international |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP2006/002165 | 3/9/2006 | WO | 00 | 9/12/2007 |
