Ventilated vacuum commutation structures

Related Application

0001This application claims the benefit of co-pending <patcit id="pcit0001" dnum="US61857905A"><text>U.S. Provisional Patent Application Serial No. 61,857,905, filed 24 July 2013</text></patcit>.

Background of the Invention

0002This invention related to an apparatus for transferring articles such as absorbent pads in the manufacture of disposable absorbent articles such as diapers, incontinence control garments or female sanitary pads as they advance along a production line.

0003In the production and manufacture of disposable products such as sanitary napkins or pants-type diapers, it frequently becomes necessary to manufacture a component of the product in one orientation, and then to rotate that component part 90° so that it is suitably oriented for use in another step in the production process. Various devices have been developed for this purpose and are known to those experienced in the industry. Examples of such apparatus are those described in <patcit id="pcit0002" dnum="US4726876A"><text>U.S. Patent Nos. 4,726,876</text></patcit>, <patcit id="pcit0003" dnum="US4880102A"><text>4,880,102</text></patcit>, and <patcit id="pcit0004" dnum="US5025910A"><text>5,025,910</text></patcit>, the disclosures of which are incorporated herein by reference.

0004As discussed above, a typical article to be reoriented by the apparatus of this invention is an absorbent pad. Because absorbent pads are typically comprised of several webs, an absorbent core and several elastic members, there is a tendency of these assemblies to contract and become distorted during transfer operations which greatly complicates handling of the pad during further processing. Control of the pad is important.

0005Other components of disposable products including ears, or extension panels, require transportation and deposition by a vacuum puck. For instance, in <patcit id="pcit0005" dnum="US8016972B"><text>U.S. Patent No. 8,016,972</text></patcit>, assigned to the same assignee as the present invention, ear webs are severed into individual ears, and rotated while held by a vacuum puck, to be applied to a traveling web such as a chassis web.

0006An ear is a component of a diaper that is grasped and pulled around the waist of a wearer. Typically, ears are secured to the diaper at a first end, and a second free end is typically equipped with securing means, such as a pressure sensitive adhesive, or hook and loop material. As a user grasps an ear and pulls the ear, elasticity provided about the waist region of the diaper allows the free end to be snugly pulled about the waist of a wearer, and coupled to the diaper. Ears can be rectangular or made of irregular shapes.

0007Typical vacuum pucks used in the prior art have rows of vacuum holes which are fed by cross-drilled ports, each being exposed to the source of vacuum by commutations, as the ports move into a zone of negative pressure in a stationary manifold. Such a configuration serves to apply vacuum sequentially to each successive row of holes. At high speeds, it has been found that air entering the vacuum ports is drawn across an article carrying face of the puck, and the air drawn into the ports can adversely impact control over the discrete components by causing misalignment, folding or other loss of total control.

Summary of the Invention

0008The apparatus of the present invention is a ventilated puck for discrete items such as portions of a disposable diaper during the manufacturing process.

0009The puck picks up an article from a first conveying means, and deposits the article onto another conveying means.

0010The puck is ventilated in order to provide for minimization of disruptive air flow. Instead of air being drawn from edges and across an article carrying face of the puck, air is able to approach vacuum ports from underneath the carrying face of the puck, proximally to the vacuum ports.

Brief Description of the Drawings

0011<ul id="ul0001" list-style="none" compact="compact"><li><figref idref="f0001">Fig. 1</figref> is a fragmentary side elevation view, shown in diagrammatic form, of a pad transferring assembly including a puck of the prior art;</li><li><figref idref="f0001">Fig. 2</figref> is a perspective fragmentary, diagrammatic view, showing related apparatus by means of phantom lines and illustrating the path of movement of discrete pieces such pads moving in accordance with the invention;</li><li><figref idref="f0002">Fig. 3</figref> is a perspective view of a non-ventilated puck of the prior art;</li><li><figref idref="f0002">Fig. 4</figref> is a perspective view of a ventilated puck of the present invention;</li><li><figref idref="f0002">Fig. 5</figref> is a bottom perspective view of an embodiment of a ventilated puck of the present invention;</li><li><figref idref="f0003">Fig. 6</figref> is a top perspective view of a ventilated puck of the present invention;</li><li><figref idref="f0003">Fig. 7</figref> is a bottom perspective view of a ventilated puck of the present invention;</li><li><figref idref="f0003">Fig. 8</figref> is a top view of a ventilated puck of the present invention;</li><li><figref idref="f0003">Fig. 9</figref> is a bottom view of a ventilated puck of the present invention;</li><li><figref idref="f0004">Fig. 10</figref> is a perspective view of an alternative embodiment of a ventilated puck;</li><li><figref idref="f0004">Fig. 11</figref> is a bottom perspective view of the puck shown in <figref idref="f0004">Fig. 10</figref>;</li><li><figref idref="f0004">Fig. 12</figref> is a a perspective view of an additional alternative embodiment of a ventilated puck;</li><li><figref idref="f0004">Fig. 13</figref> is a bottom perspective view of the puck shown in <figref idref="f0004">Fig. 12</figref>;</li><li><figref idref="f0004">Fig. 14</figref> is a front view of a rotating body carrying rotating ventilated pucks;</li><li><figref idref="f0005">Fig. 15</figref> is a ported vacuum drum with ear retaining portions of the prior art;</li><li><figref idref="f0005">Fig. 16</figref> is a side view of a vacuum drum of the prior art;</li><li><figref idref="f0005">Fig. 17</figref> is a perspective view of a ventilated shell structure of the present invention for mounting to a drum to form a continuous ventilated drum surface;</li><li><figref idref="f0006">Figs. 18a and 18b</figref> are a perspective view, with an exploded portion, of assembled ventilated shell structures of <figref idref="f0005">Fig. 17</figref>;</li><li><figref idref="f0006">Fig. 19</figref> is a front view of assembled ventilated shell structures of <figref idref="f0005">Fig. 17</figref>, showing vacuum manifolds adjacent both sides of the assembled drum, and ventilation provided through the shell surface (outside of a product contact region(s);</li><li><figref idref="f0006">Fig. 20</figref> is a rear perspective view of an alternate embodiment of a ventilated shell structure with a nested ventilation and vacuum commutation construction;</li><li><figref idref="f0007">Fig. 21</figref> is a top perspective view of the ventilated shell structure of <figref idref="f0006">Fig. 20</figref>;</li><li><figref idref="f0007">Figs. 22a and 22b</figref> are a perspective view, with an exploded portion, of assembled ventilated shell structures of <figref idref="f0006">Fig. 20</figref>;</li><li><figref idref="f0007">Fig. 23</figref> is a front view of assembled ventilated shell structures of <figref idref="f0006">Fig. 20</figref>, showing vacuum manifolds adjacent both sides of the assembled drum, and ventilation provided through the shell surface (outside of a product contact region(s);</li><li><figref idref="f0008">Fig. 24</figref> is a top perspective view of a second alternate ventilated shell structure of the present invention;</li><li><figref idref="f0008">Fig. 25</figref> is a bottom perspective view of the ventilated shell structure of <figref idref="f0008">Fig. 24</figref>;</li><li><figref idref="f0008">Fig. 26</figref> is a top view of the ventilated shell structure of <figref idref="f0008">Fig. 24</figref>;</li><li><figref idref="f0009">Fig. 27</figref> is a top perspective view of a third alternate ventilated shell structure of the present invention, showing a patterned vacuum commutation port configuration;</li><li><figref idref="f0009">Fig. 28</figref> is a bottom perspective view of the ventilated shell structure of <figref idref="f0009">Fig. 27</figref>;</li><li><figref idref="f0009">Fig. 29</figref> is a top view of the ventilated shell structure of <figref idref="f0009">Fig. 27</figref>.</li></ul>

Description of the Preferred Embodiment

0012Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention which may be embodied in other specific structures. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims.

0013Referring more particularly to the drawings, there is seen in <figref idref="f0001">Fig. 1</figref> an apparatus 10 carrying pucks, or transfer heads 16, of the prior art. The apparatus 10 is adapted to receive a series of articles 14 from an upstream conveyor or vacuum drum (not shown) onto a pad turning device 12 which includes a plurality of radially extending transfer heads 16.

0014The location where articles 14 are received from the upstream point onto the pucks 16 is known as the pick up point. The location where articles 14 are deposited from the pucks 16 to a downstream drum or conveyor 20 is known as the lay down point.

0015The pad turning device 12 may be, for example, a rotary pad turner of the type more fully described in <patcit id="pcit0006" dnum="US5025910A"><text>U.S. Patent No. 5,025,910</text></patcit> which is incorporated herein by reference. The articles 14 can be of any type, but are typically absorbent pads, ears, or extension panels. During manufacturing, each of these requires transportation and deposition by a vacuum puck, and sometimes rotation or reorientation of a discrete piece is also desirable prior to deposition onto another portion of an absorbent article. Such pad turning devices 12 are especially needed and are suited for use in connection with the manufacture and packaging of sanitary napkins as well as absorbent pads which are used in the assembly of disposable garments such as adult incontinence garments or children's training pants.

0016Also seen in <figref idref="f0001">Fig. 1</figref>, articles 14 are successively and individually picked-up by the transfer heads 16 of the pad transfer device 12. In the illustrated embodiment, the articles 14 are picked up from a vacuum drum (not shown). Various conventional conveying and direction changing devices such as rollers may be employed in the feeding of the web and do not form a part of this invention.

0017After the articles 14 have been rotated 90 degrees, they are deposited at the lay down point onto a second vacuum source, for example a drum 20. A conveyor 28 or the like transport the articles 14 for further processing or to a packaging device, as required by a particular application. Alternatively, the deposition point can be for instance a coupling point for an ear or an extension panel onto a chassis web, such as shown and described in <patcit id="pcit0007" dnum="US8016972B"><text>U.S. Patent No. 8,016,972</text></patcit>, incorporated herein by reference.

0018Referring to <figref idref="f0001">Fig. 2</figref>, there is seen a diagrammatic depiction of the travel path of the web 22 and the resultant pads 14 which are formed therefrom. In this depiction the various apparatus have been eliminated but are partially illustrated by means of phantom lines.

0019As can be seen, the article is rotated 90° from the pick up point to the lay down point, and is also stretched during this time it spends on the puck 16. In some instance however, it is not necessary to rotate the article between pick up and lay down, depending on the design of the article being produced or the manufacturing technique used.

0020As shown in <figref idref="f0002">Fig. 3</figref>, a perspective view of an embodiment of a prior art puck 16 prior art is shown. At high speeds, it has been found that air entering vacuum ports 32 is drawn across an article carrying face 36 of the puck 16, and the air drawn into the ports 32 can adversely impact control over the discrete components by causing misalignment, folding or other loss of total control.

0021Referring now to <figref idref="f0002">Fig. 4</figref>, a perspective view of one embodiment of a ventilated puck 40 of the present invention is shown. Air is drawn into commutation ports 32 by commutation pipes 38. The pipes 38 carry a preferably radially shaped vented article carrying structure 36, although flat pucks can also be used. A plurality of air supplying vents 34 are situated about vacuum commutation ports 32. Air supply vents 34 receive air drawn through sides 43 of the ventilated puck 40, and drawn through the air surrounding the commutation pipes 38. The ventilated puck 40 preferably lacks solid sidewalls 30 as shown in prior art pucks such as <figref idref="f0002">Fig. 3</figref>, allowing the ingress of air through the void sides 42 into the interior of the puck 40, as well as through air supplying vents 34 not overlain by a discrete piece of material. The air enters the interior vacuum ports 44 from the underside of article carrying structure 36, and the air is drawn into proximally situated vacuum ports 32.

0022The commutation pipes 38 are rigid enough to support the vented article carrying structure, and rigid enough to withstand collapse due to applied vacuum. And although the commutation pipes 38 are depicted as narrow square tubular in shape leading to the small and circular vacuum commutation ports 32, the commutation pipes 38, the air supplying vents 34, and the vacuum commutation ports 32 can take different cross-sectional shapes, such as star shaped, circular, oval, rectangular, etc.

0023A pattern of vacuum ports 32 is provided on the surface of article carrying structure 36 through which the internal vacuum acts to draw the pads 14 towards the surface. It is clear that this technology can be applied to the transfer and placement of many different types of articles in the disposable goods industry and other industries as well.

0024Metal laser sintering is a good way to make the products of the present invention.

0025Referring now to <figref idref="f0002">Fig. 5</figref>, vacuum is drawn through interior vacuum ports 44 of commutation pipes 38 in a manner such as shown in <patcit id="pcit0008" dnum="US7770712B"><text>U.S. Patent No. 7,770,712</text></patcit>, which is incorporated by reference. Commutation pipes 38 extend between and are coupled to a vacuum port plate 46 and the article carrying structure 36. Together, the commutation pipes 38, vacuum port plate 46 and the article carrying structure 36 of the puck 16 are rotated and supplied with vacuum as previously described.

0026Referring now to <figref idref="f0003">Fig. 6</figref>, a top perspective view of the article carrying structure 36 of the puck 16 is shown. The article carrying structure, as previously described, has a plurality of circular vacuum commutation ports 32 and air supplying vents 34, both of which can vary in shape, size, or distribution. A plurality of clearance holes 52 for mounting the puck 16 are shown. As shown on <figref idref="f0003">Fig. 7</figref>, Corresponding clearance holes 52 on the vacuum port plate 46 for receiving a coupling means (such as a screw) through both sets of clearing holes 52, and are used to couple the puck 16 to a receiving surface/apparatus (not shown). Sidewalls 50 of the vacuum port plate 46, together with a vacuum manifold (not shown), provide vacuum to the regions defined by the sidewalls 50. <figref idref="f0003">Figs. 8 and 9</figref> show a top and a bottom view of a ventilated puck 16 of the present invention.

0027In the embodiment depicted in <figref idref="f0003">Figs. 6-9</figref>, a plurality of side and top ventilated pucks 16 can be joined together on a rotating device (e.g., <figref idref="f0004">Fig. 14</figref>) such that the article carrying structures 36 of the pucks 16 present a radius around the rotating device. In a preferred embodiment, the article carrying structures 36 of the pucks 16 are trapezoidal in top view, and if a flat vacuum port plate 46 is used, the commutation pipes 38 will be of varying lengths to accommodate the variable distance between the flat port plate 46 and curved article carrying structure 36. Because the article carrying structures 36 are curved, the portion of the commutation pipes 38 that meet the article carrying structures 36 are also curved. The portion of the commutation pipes 38 that meet the flat port plates 46 are flat.

0028Referring now to <figref idref="f0004">Figs. 10-13</figref>, an alternative embodiment of a ventilated puck 234 is shown. As can be seen from <figref idref="f0004">Fig. 14</figref>, two types of pucks are provided, non-rotating pucks 234A and rotating pucks 234B. The non-rotating pucks 234A carry ears (not shown) that do not require rotation, and the rotating pucks 234B carry ears requiring rotation. As the ear turner assemblies 200R and 200L go through their rotation, ears 12 are picked up from the ear die/anvil station 230/232 and rotate about the rotator 200, while every rotating puck 234B also rotates radially during rotation of the rotator 200. The ears are then deposited onto chassis web and bonded thereto, for instance by ultrasonic bonding ring, where the resulting product is sent downstream for further processing.

0029Again in this embodiment commutation pipes 38 extend between and are coupled to a vacuum port plate 130 and the article carrying structure 36. Together, the commutation pipes 38, vacuum port plate 46 and the article carrying structure 36 of the puck 16 are rotated and supplied with vacuum as previously described. A rotating body coupling structure 120 is provided for attaching to the rotating unit 200.

0030The rotation and operation of the non-rotating pucks 234A and rotating pucks 234B are described in <patcit id="pcit0009" dnum="US925033A"><text>U.S. Application Serial No. 12/925,033</text></patcit>, and <patcit id="pcit0010" dnum="US8172977B"><text>U.S. Patent Nos. 8,172,977</text></patcit>, <patcit id="pcit0011" dnum="US8106972B"><text>8,106,972</text></patcit>, and <patcit id="pcit0012" dnum="US7780052B"><text>7,780,052</text></patcit>, each of which is incorporated by reference.

0031Referring now to <figref idref="f0005">Fig. 15</figref>, a ported vacuum drum (or anvil roll) with ear retaining portions of the prior art is shown. Anvil roll 114 is shown carrying ear forming material 7 (and later, after being severed, individual ears 8) in phantom. The anvil roll 114 is formed with two vacuum portions 116 separated by a center groove portion 118. The vacuum portions 116 are preferably mirror images of each other. The anvil roll 114 is symmetrical about a center plane through its circumference. Each vacuum portion 116 contains several circumferential rows of circular vacuum holes 24. Each vacuum portion 116 may also contain a circumferential groove 120 with an additional circumferential row of vacuum holes 24 located in the circumferential groove 120.

0032Referring now to <figref idref="f0005">Fig. 16</figref>, a side view of the anvil 114 of the prior art is shown. The vacuum slot 128 contains a plurality of vacuum holes 24 that allow commutation of the vacuum to the entire ear vacuum hole pattern 126, allowing the pattern 126 to be activated simultaneously, as opposed to each of the rows that comprise the vacuum of vacuum holes 24 being enabled one at a time. The vacuum pattern 126 is activated utilizing drilled ports 28 that communicate the vacuum from the slot 128 to the individual holes 24 of the pattern 126. It should be noted that the pattern 126 can also be provided with a depressed slot configuration so that it too is all simultaneously enabled with vacuum. The remaining vacuum holes 24 provided on the anvil roll 114 are enabled sequentially, by known vacuum commutation method utilizing cross drilled ports 28.

0033Improvements to the prior art drums for carrying webs either continuous or of discrete pieces such as ears 8 of <figref idref="f0005">Figs. 15 and 16</figref> are described in <figref idref="f0005 f0006 f0007 f0008 f0009">Figs. 17-29</figref>.

0034Referring now to <figref idref="f0005 f0006">Figs. 17-19</figref>, a top vented transfer roll shell 300 is disclosed. Shell 300 is mounted to a rotating body (not shown) to form a continuous ventilated drum surface. In cases where there are vacuum manifolds 320 adjacent both sides of the drum (see, e.g., <figref idref="f0006">Fig. 19</figref>), side ventilation is not possible, therefore ventilation is provided through the shell surface 36 outside of the product contact region(s). In this embodiment vent channels 302 are provided, preferably at outer edges of the top vented transfer roll shell 300. Air passes under the article carrying surface 36 from the vent channels 302 underneath the surface 36 to both a first zone of air supplying vents 34/and commutation ports 32, and to a zone of exclusively air supplying vents 34. Vacuum is drawn from the vacuum manifolds 320 at the under surface of the shell 300, and through commutation ports 32 as shown in cross section at <figref idref="f0006">Fig. 18B</figref>. The arrangement of air supplying vents 34 and commutation ports 32 can be varied and patterned based on the configuration of the pieces intended to be carried. The ventilated shell 300 contains nested ventilation and vacuum commutation construction through the article carrying surface.

0035As can be seen in <figref idref="f0006">Fig. 18A</figref>, a plurality of top vented transfer roll shells 300 can be provided to create a vacuum roll or drum. In the depicted embodiment, four top vented transfer roll shells 300, are provided, each accounting for 90 degrees of the periphery of the drum.

0036In <figref idref="f0006 f0007">Figs. 20-23</figref>, top vented vacuum ring 400 is disclosed, for use where vacuum manifold 320 is adjacent to sides of a drum formed by the rings 400 precludes side ventilation (see <figref idref="f0007">Fig. 23</figref>). In this embodiment, vacuum applied from the sides of the ring 400 through vacuum commutation channels 402 allows vacuum to be pulled through commutation ports 32 from the surface of the commutation ports 32 exposed to the interior of the ring 400, and through the ports 32 to the exterior article carrying surface of the ring 400. A plurality of air supplying vents 40 are supplied at the surface of the ring 400, so that the surface of the ring will contain an arrangement of both vents 40 and commutation ports 32. Venting and air supply is first from the outside of the shell surface outside of product contact regions, next through channels 404 to underneath product contact regions, next out through vents 40 underneath product contact regions and next drawn into ports 32.

0037In <figref idref="f0008">Figs. 24-26</figref>, a top and side vented vacuum pattern plate 500 is disclosed similar in construction to pucks previously described. Commutation ports 32 are provided on article carrying surface 35 coupled with commutation pipes 38. A secondary zone of aggressive channeled and interconnected ports 37 are also coupled commutation pipes 38 between article carrying surface 36 and vacuum port plate 46.

0038<figref idref="f0009">Figs. 27-29</figref> show a similar top and side vented vacuum pattern plate 600, showing a patterned vacuum commutation port 32 configuration.

0039The foregoing is considered as illustrative only of the principles of the invention. Furthermore, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims.