Patent Publication Number: US-6699167-B2

Title: Cushioning conversion machine and method

Description:
This application is a continuation of PCT/US01/19632 Jun. 6, 2001which claims benefit of Ser. No. 60/212,520 Jun. 19, 2000. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to a cushioning conversion machine and method. More particularly, the present invention relates to improved forming assemblies and/or forming steps for cushioning conversion machines and methods. 
     BACKGROUND OF THE INVENTION 
     In the process of shipping an item from one location to another, a protective packaging material generally is placed in the shipping case, or box, to fill any voids, to cushion, to block and/or to brace the item during the shipping process. Various types of packing products have been used to pack articles in containers for shipment, including a crumpled paper cushioning product which is biodegradable, recyclable, and composed of a renewable resource, making it an environmentally responsible choice. A particularly desirable crumpled paper product is produced by crumpling one or more plies of sheet stock material, such as kraft paper. The sheet stock material is crumpled and folded upon itself to form a crumpled cushioning dunnage product having lateral pillow portions with a central band therebetween. 
     The conversion of multi-ply sheet material into a crumpled cushioning product may be accomplished by a cushioning conversion machine, such as those disclosed in U.S. Pat. Nos. 4,750,896; 4,884,999; and/or 5,607,383. (These patents are assigned to the assignee of the present application and their entire disclosures are incorporated by reference.) Each of the cushioning conversion, machines disclosed in the above-identified patents includes a conversion assembly which converts sheet stock material composed of one or more plies into a relatively less dense three-dimensional cushioning product. The conversion assembly includes a forming assembly which forms the sheet stock material into a strip having lateral pillow portions. The conversion assembly also includes a feeding assembly which is positioned downstream of the forming assembly and which pulls the stock material through the forming assembly and connects the strip along a central band. 
     The forming assemblies in the above-identified patents each comprise an external forming device such as a converging chute and an internal forming device such as a wire frame. The stock material travels through the external forming device and folds around the internal forming device to form the strip of cushioning. This inward folding may result in lateral regions of the stock material experiencing excessive edge tension which sometimes results in ripping or tearing of the stock material, particularly at the lateral edges. In addition, narrower widths of stock material have a tendency to shift laterally within the forming assembly, leading to inconsistently and often improperly formed cushioning products. This also leads to such problems as pads not forming properly from the first portion of a new paper supply, such as a stock roll. 
     In addition, the resiliency of the pillow portions encourages opening up or separation of the connected portions during manipulation of the dunnage product. The separation of the connected portions is commonly referred to as “un-zippering” which generally begins at a longitudinal end of the dunnage product and progresses along the length of the connected portions. This problem also can be caused by the misalignment of the stock material in the forming assembly, as well as by inadequate connection of the overlapped portions of the stock material. This can occur when the overlapped portions have more layers of stock material than are necessary and/or when the overlapped portions include layers of stock material which have been crumpled and have a tendency to separate from adjacent layers. 
     Over the years, forming assemblies have been modified, improved or otherwise changed. Despite these past modifications, improvements and changes, a need remains for further improvements in cushioning conversion machines and methods with reduced edge tension and/or tearing associated therewith, while at the same time providing sufficient lateral control to form an acceptable cushioning product, and providing sufficient connection to maintain the shape of the cushioning product, with different widths and/or weights of stock material. 
     SUMMARY OF THE INVENTION 
     The present invention provides improved forming assemblies and/or forming steps for cushioning conversion machines and methods which address one or more of the aforementioned problems. In general, the present invention provides a cushioning conversion machine having a novel former around which a sheet material is folded to form an improved cushioning product. The former minimizes resistance to the flow of the stock material around the former while providing desirable cushioning properties in the formed cushioning product. The former softens the damming and/or reduces the temporary accumulation of the sheet material that was found to occur in prior art formers and provides for a smoother transition of the flow of crumpled sheet material around the former. The former also encourages the stock material to crumple in lateral regions and minimizes or restricts crumpling in a central region as the strip of cushioning is formed so that the feed assembly can form a better connection between the relatively uncrumpled layers of stock material in a portion of the strip of cushioning to maintain the shape of the formed cushioning product. 
     According to one aspect of the invention, a cushioning conversion machine for converting sheet stock material into a relatively lower density cushioning product as the sheet stock material moves through the machine from an upstream end toward a downstream end includes a feeding assembly and a forming assembly. The forming assembly includes a former with a top portion having a pair of generally longitudinally extending and coplanar converging lateral top edges. The former also has at least one lateral longitudinally spaced side edge depending from each of the top edges and inclined relative to the plane of the top edges. 
     According to one embodiment of the invention, the machine further includes support members which form the converging top edges and one or more ribs or rib portions forming the side edges. The support members may support mandrel portions which each have a greater cross-sectional area than the support members and which increase a height dimension and a width dimension of the former in the vicinity of the mandrel portions. In addition or in the alternative, the at least one rib may have a U-shape and/or may include side leg portions and bottom leg portions, the side leg portions forming the at least one inclined side edge. The bottom leg portions may form at least one bottom inclined edge extending from a vertical plane containing a longitudinal axis of the former, laterally outwardly and inclined toward the upstream end of the machine. Additionally or alternatively, the former may include a lateral guard plate mounted above the bottom leg portions. Additionally or alternatively, the former may include a base plate forming a substantially flat central surface extending substantially the length of the former. The base plate may be spaced relative to the chute to minimize crumpling of the central portion of the stock material. The forming assembly may additionally or alternatively include a pad width adjustment device which is selectively adjustable to change the width of the cushioning product by restricting the width or the height of a path of the sheet material. 
     According to another aspect of the invention, a cushioning conversion machine for converting sheet stock material into a relatively lower density cushioning product as the sheet stock material moves through the machine from an upstream end toward a downstream end includes a feeding assembly and a forming assembly. The forming assembly includes a former with a bottom plate and one or more generally coplanar longitudinally spaced bottom edges extending laterally outwardly from the bottom plate. The bottom edges are inclined relative to a vertical plane containing a longitudinal axis of the former. The bottom edges are inclined laterally outward and toward the upstream end of the machine. 
     According to yet another aspect of the invention, a method of converting sheet stock material having a central portion, lateral portions and lateral edge portions into a relatively lower density cushioning product, includes feeding the sheet stock material through a forming assembly, folding the lateral edge portions over the central portion to form an unconnected strip having lateral regions and a central region, causing alternate lateral side regions of the unconnected strip to dam behind inclined edges of a former to crumple the lateral side regions thereof, passing crumpled alternate lateral side regions thereof over the inclined edges; and connecting the central region thereof to form a connected strip. 
     According to another aspect of the invention, a former for use in a cushioning conversion machine to convert sheet stock material into a relatively lower density cushioning product as the stock material moves through the machine from an upstream end toward a downstream end, includes a top portion having a pair of generally longitudinally extending and coplanar converging lateral top edges. The former also includes one or more lateral longitudinally spaced side edges depending from the top edges and inclined relative to the plane of the top edges. 
     According to still another aspect of the invention, a cushioning conversion machine for converting sheet stock material into a relatively lower density cushioning product as the sheet stock material moves through the machine from an upstream end toward a downstream end. The machine includes a feeding mechanism for moving the sheet stock material through the machine, and a forming mechanism for forming the sheet stock material into the shape of the cushioning product. The forming mechanism includes a pair of generally longitudinally extending and coplanar converging lateral top edges, and one or more lateral longitudinally spaced side edges depending from the top edges and inclined relative to the plane of the top edges. 
     The foregoing and other features of the invention are hereinafter fully described and particularly pointed out in the claims. The following description and annexed drawings set forth in detail a certain illustrative embodiment of the invention, this being indicative, however, of but a few of the various ways in which the principles of the invention may be employed. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a cross-sectional side view of a cushioning conversion machine with a forming assembly according to the present invention. 
     FIG. 2 is a top view of the cushioning conversion machine of FIG. 1 with a top of the housing of the machine removed to show the forming assembly. 
     FIG. 3 is a cross-sectional end view of the cushioning conversion machine as seen along line  3 — 3  of FIG.  2 . 
     FIG. 4 is an enlarged cross-sectional side view of the forming assembly shown in FIG.  1 . 
     FIG. 5 is an enlarged top view of the forming assembly shown in FIG.  2 . 
     FIG. 6 is a partial cross-sectional end view of a portion of a constant entry roller on the machine as seen along line  6 — 6  of FIG.  2 . 
     FIG. 7 is a partial cross-sectional side view of a cushioning conversion machine with an alternative forming assembly according to the present invention. 
     FIG. 8 is a top view of the cushioning conversion machine of FIG. 7 with a top of the housing of the machine removed to show the alternative forming assembly. 
     FIG. 9 is an enlarged view of a portion of the forming assembly shown in FIG.  7 . 
    
    
     DETAILED DESCRIPTION 
     A cushioning conversion machine  10  in accordance with the present invention is shown in FIGS. 1-3. The machine has an upstream or “feed” end  12  and a downstream or “discharge” end  14 . The machine is positioned in a substantially horizontal manner in the illustrated embodiment whereby a longitudinal line or axis  16  (FIG. 2) from the upstream end to the downstream end is substantially horizontal. 
     In the following paragraphs (and in the context of the present invention), the downstream direction and/or the longitudinal dimension corresponds to the flow of stock material through the cushioning conversion machine  10  from the upstream end  12  toward the downstream end  14  (the upstream direction being opposite the downstream direction). The transverse dimensions correspond to central vertical and horizontal planes passing through the longitudinal axis of the cushioning conversion machine when the longitudinal axis is horizontally oriented. More specifically, the lateral transverse dimension refers to the horizontal plane or “width” of the cushioning conversion machine (top-to-bottom in FIGS. 2,  5  and  8 ) and the non-lateral transverse dimension refers to the vertical plane or “height” of the cushioning conversion machine (top-to-bottom in FIGS. 1,  3 ,  4 ,  6 ,  7  and  9 ). Certain directional modifiers may be used, such as upper, lower, upwardly, top, bottom, etc. These terms correspond to the illustrated orientation, however, the directional modifiers are used solely for convenience, they are not intended to limit the invention to a particular orientation of the cushioning conversion machine. 
     The machine  10  generally includes a stock supply assembly  18 , a forming assembly  20 , a feed assembly  22 , a severing assembly  24 , and a post-severing assembly  26  (one or more of which may be referred to generally as “conversion assemblies”). The machine also includes a frame  28  which supports one or more of the assemblies in the machine, and/or a housing  30  which encloses one or more of the assemblies as well as some or all of the frame. 
     In operation, the stock supply assembly  18  supplies multi-ply sheet stock material (not shown) to the forming assembly  20 . The sheet stock material generally is multi-ply sheet material, for example, a three-ply sheet material such as kraft paper, and is referred to as paper in the following paragraphs, although other forms of single or multi-ply sheet stock material may be used. The forming assembly causes inward folding and crumpling of lateral portions of the paper over a relatively uncrumpled central portion of the paper to form lateral pillow portions of a continuous unconnected strip. The feed assembly  22  pulls the paper from a stock roll (not shown), through the stock supply assembly, and through the forming assembly, and also connects or stitches the central band of the strip to form a connected strip of cushioning. As the connected strip travels further downstream from the feed assembly, the severing assembly  24  severs cushioning products from the strip into sections or pads of desired length. These sections travel through the post-severing assembly  26  for use as dunnage products. 
     Turning to a more detailed description of the various assemblies, the stock supply assembly  18  supplies the paper, such as the noted three-ply kraft paper, and provides a gradual transition between the supply of the paper, such as from the stock roll, to the forming assembly  20  and the inward turning of lateral edges thereby. Such an arrangement is believed to reduce edge tension in the paper and/or otherwise to enhance the conversion process. 
     The illustrated stock supply assembly  18  includes two laterally spaced brackets, each generally having a sideways “U” shape with two walls  42 ,  44  extending perpendicularly outwardly from a connecting wall  46  attached to the machine  10 . The lower walls  42  have open slots in their distal ends to cradle a supply rod (not shown) rotatably supporting the stock roll. As the paper is pulled through the machine by the feed assembly  22 , the supply rod and/or a hollow tube of the stock roll will freely rotate to dispense the paper from the stock roll. The upper walls  44  of the U-shape brackets support a paper ply separating device  50  and a constant-entry device  52 . 
     The paper separating device  50  separates the plies of paper prior to their passing to the forming assembly  20 . The separating device includes a pair of laterally aligned mounting brackets  56  and a plurality of separating members. The number of separating members, namely three—an upper member  58 , an intermediate member  60 , and a lower member  62 —generally corresponds to the number of plies or webs of paper being utilized. The separating members are sized to axially extend the entire transverse dimension (i.e., width) of the paper. In the separating device, the separating members are horizontally and vertically spaced separating bars which extend in a linear transverse path in a direction substantially perpendicular to the path of the paper. The separating members are spaced along a line inclined relative to the vertical with the upper member  58  being located further downstream than the lower member  62 . This inclined orientation of the separating members is believed to reduce edge tension in the paper and/or otherwise to enhance the conversion process. 
     The separating members  58 ,  60 ,  62  have a circular cross-sectional shape, which may not have the same diameter along its entire axial dimension. The separating members include end portions  64  and a central portion  66  extending between the end portions. The central portion  66  of the separating member occupies a majority of the member&#39;s axial length, and the end portions  64  are inwardly tapered relative to the central portion towards respective ends of the member. The inwardly tapered lateral end portions  64  are positioned to engage the outer ends of the lateral portions of a ply of paper. In this manner, lateral portions of the plies of paper are free to move inwardly in the same direction as the forming assembly  20  inwardly turns the lateral edges of the paper. This allows a gradual, rather than an abrupt, transition between the separating device  50  and the forming assembly  20  thereby reducing the chance of excessive edge-tension and/or otherwise enhancing the conversion process. In the illustrated embodiment, the upper separating member  58  has a smaller diameter than the lower  62  and intermediate  60  separating members since tearing of lateral edge portions of the paper is less common on the upper (inner) ply of the paper than the lower (intermediate and outer) plies and thus less relief is required to eliminate tearing. 
     The supply assembly brackets  40  also cooperate to support the constant-entry device  52  which is rotatably mounted on the distal ends of the upper bracket walls  44 . The constant-entry device provides a non-varying point of entry for the paper from the stock roll into the separating device  50  and forming assembly  20  independent of the diameter of the stock roll. Thus when a different diameter roll is used and/or as the stock roll dispenses paper and decreases in diameter, the point of entry of the paper into the separating device remains constant. This consistency is believed to facilitate the production of a uniform cushioning product. 
     As the paper is drawn into the forming assembly  20  from the stock roll it exerts a downward force on a constant-entry roller  70  of the constant-entry device  52  by reason of the pulling force needed to rotate the stock roll. The illustrated constant-entry device  52  additionally functions temporarily as a force dampening device during a high tension situation, such as during start up. As shown in FIG. 6, the constant-entry device includes the constant-entry roller  70  which has a sleeve  72  and a rod  74  whose ends are resiliently supported and guided by spring-loaded mechanisms  76 . 
     Each spring-loaded mechanism  76  includes a tubular housing  78 , an elongated guide slot  80 , and a spring  82 . The spring  82  resiliently supports the end of the constant-entry roller&#39;s rod  74 . During start up, when the stock roll must be accelerated from a rest condition to a rotational speed dictated by the feed rate of the feed assembly  22  (FIG.  1 ), the springs yield and release excessive tension that may cause tearing in the paper. Once the high-tension situation has been resolved and the downward force on the constant-entry roller  70  is normalized the springs bias the rod to its upper position within the slots. For further information about these and other types of separating devices and/or constant-entry devices, U.S. application Ser. No. 09/229,459 filed on Jan. 12, 1999 is hereby incorporated by reference in its entirety. This application is commonly owned by the assignee of the present invention. 
     Returning to FIGS. 1-6, after the paper is pulled from the stock roll over the constant-entry roller  70  and through the separating device  50 , it is pulled through the forming assembly  20 . The forming assembly includes an internal forming device, such as a three-dimensional shaping member or former  90 , an external forming device, such as a converging chute  92 , and a pad width adjustment device  94 . The chute and the former are positioned within a common envelope defined by the machine&#39;s housing  30 . The paper travels between the former and a lower portion of the housing of the machine  10  and then into the chute. During the downstream travel of the paper, the forming assembly causes lateral regions of the paper to crumple and to fold inwardly to form a strip of cushioning having lateral pillow portions. As the strip emerges from the chute, the strip is guided into the feed assembly  22  which connects the layers of paper in a central region of the strip to maintain the shape of the resulting cushioning product. 
     As best seen in FIGS. 3-5, the converging chute  92  has an upstream inlet  96 , a downstream outlet  98 , and substantially continuous surfaces  100  (i.e., walls) therebetween which converge from the inlet toward the outlet and define a turning space. The former  90  includes one or more mounting brackets  102  for mounting the former to the machine&#39;s housing  30 , frame  28  and/or the chute such that the former extends into the converging chute. One bracket may be a suspension strap  104  cantilevered from an upstream section of the machine&#39;s housing to an upstream portion of the former. The suspension strap is adjustable to selectively position the former at a desired angle relative to the chute. 
     The former  90  has a generally converging shape along a longitudinal dimension from an upstream end  106  toward a downstream end  108 , with converging top surfaces or edges formed by an upper or top portion  110 . The converging edges in the illustrated embodiment are formed by a pair of coplanar converging leg portions  112 , generally constructed of a bar material, such as metal rod. The converging leg portions give the top a generally V-shape when viewed from above, or more particularly a shape like a “V” with a cut-off vertex and the wider end oriented toward the upstream end  12  of the machine  10 . 
     The former  90  further includes mandrel portions  114  which are attached to the top portion  110  to encourage and/or to induce lateral edges of the paper to curl inwardly as the paper moves over the former. More specifically, the converging leg portions  112  support the mandrel portions which have a greater cross-sectional area than the converging leg portions. The mandrel portions project beyond the coplanar converging leg portions of the top in both the lateral and non-lateral transverse directions. Thus, the converging leg portions which support and position the mandrel portions generally adjacent the outlet  98  of the chute  92 , are substantially symmetrical relative to the vertical center plane of the former, and generally aligned longitudinally with the inlet  96  and the outlet  98  of the chute. 
     Each of the mandrel portions  114  has an upstream cone-shape section  116 , a cylindrical-shape section  115  and a downstream cone-shape section  120 . In the illustrated embodiment, the mandrel portions have a concentric core through which the downstream ends of the converging leg portions  112  extend to allow the mandrel portions to be selectively moved along the converging leg portions, thereby providing longitudinal adjustment of the mandrel portions. However, mandrel portions formed integrally with the supporting portions are possible with, and contemplated by, the present invention. 
     The former  90  also includes lateral side edges and bottom edges, which in the illustrated embodiment preferably are formed by one or more ribs constructed of a bar material, such as metal rod. The illustrated former includes three ribs: an upstream rib  130 , an intermediate rib  132 , and a downstream rib  134 . The ribs have a generally “U” shape when viewed from the downstream end (see FIG.  3 ), the outer lateral sides of the “U” forming the lateral side edges and the bottom of the “U” forming the bottom edges. In the illustrated embodiment, the ribs are inclined relative to a perpendicular to the plane of the converging leg portions  112  such that such that a portion of each rib is closer to one of the converging leg portions and further downstream than another portion of the rib, as will be further explained below. 
     More specifically, the upstream rib  130  has a pair of side leg portions  140  connected together by a bottom leg portion  142 . The upper ends of each of the upstream side leg portions are connected, via a rounded corner, to the upstream end of respective converging leg portions  112  of the V-shape top portion  110 . The intermediate rib  132  also has a pair of side leg portions  144  connected through bottom leg portions  146 . The upper ends of each of the intermediate side leg portions are connected to aligned sections of the converging leg portions of the V-shape top between the upstream  106  and the downstream  108  ends of the former  90 , and are longitudinally spaced downstream of the upstream rib. The downstream rib  134  also has a pair of side leg portions  148  connected through bottom leg portions  150 . The upper ends of each of the downstream side leg portions are connected to aligned sections of the converging leg portions of the V-shape top and are longitudinally spaced downstream of the intermediate rib. The bottom leg portions of the ribs generally are coplanar, and the downstream rib generally is upstream of the mandrel portions  114 . 
     The side leg portions  140 ,  144 ,  148  of each rib  130 ,  132 ,  134 , respectively, are inclined relative to the plane of the converging leg portions  112  of the top portion  110 , and more particularly, the side leg portions depend from the top from a higher downstream end angled toward a lower upstream end. In the illustrated embodiment, when viewed from the side (FIG. 4) the side leg portions  140  of the upstream rib  130  are angled at approximately 36° relative to the vertical  141  while downstream rib  148  is angled at approximately 54° relative to the vertical  149 , and intermediate rib  144  is angled at about 60° relative to the vertical  145 , although other angles may be used. It has been found that the forward inclination of the ribs facilitates the formation of crumpled portions of the paper as well as the subsequent flow of those crumpled portions over the ribs as the paper moves in the downstream direction. A more desirable crumpling pattern is formed from the adjacent ribs having different inclinations. 
     The bottom leg portions  146 ,  150  of the downstream and intermediate ribs  132 ,  134 , respectively, extend at an angle upstream and outward from a vertical center plane toward an upstream end laterally outward and downstream, and terminate at lower ends of the respective side leg portions  144 ,  148 . When viewed from above, such as in FIG. 2, the bottom leg portions form a herringbone pattern with adjoining bottom leg portions of the intermediate and downstream ribs, respectively, forming a “V” shape opening toward the upstream end  106  of the former  90 . Although in the illustrated embodiment the ribs  130 ,  132 ,  134 , and the top  110  preferably are formed from a bar stock that forms a wire-frame, the former could have generally solid surfaces or could otherwise be formed of different materials. 
     As the former  90  converges toward the downstream end  108 , successive ribs  130 ,  132 ,  134  decrease sequentially in height and in width whereby the space enclosed by the ribs sequentially decreases in the downstream direction. Because of the inclined features of the ribs, the overall width of each rib decreases, from an upstream portion of the rib adjacent the intersection between the bottom leg portions  142 ,  146 ,  150  and the respective side leg portions  140 ,  144 ,  148 , toward a downstream portion adjacent the intersection of the side leg portions and the converging leg portions  112  of the top  110 . The angled and converging features of the edges formed by the ribs and the top reduce the damming of the paper that occurs relative to the damming in prior art devices, while still providing desirable crumpling, and easing the transition of the crumpled paper past alternate lateral sides of the ribs, thereby also minimizing sudden changes in the tension in the paper that may lead to tearing. 
     The former  90  further includes a longitudinally extending base plate  152  which has a rectangular strip shape. The base plate extends from the upstream rib  130 , under and past the intermediate rib  132 , under and past the downstream rib  134  toward the downstream end  108  of the former. More particularly, the upstream end  106  of the base plate is attached (e.g., welded) to a laterally central section of the bottom leg portion  142  of the upstream rib and one or more intermediate portions of the base plate is attached (e.g., welded) to the bottom leg portions  146 ,  150  of the intermediate and/or downstream ribs  132 ,  134 , respectively. The downstream end of the base plate extends freely beyond the downstream rib. 
     The illustrated base plate  152  has a substantially flat surface separated into upstream and downstream sections  154 ,  156 , respectively, which are angled relative to each other. In the illustrated embodiment, the angle between the two sections of the base plate is approximately six degrees. As a result, when the former  90  is mounted in the machine  10 , the downstream and upstream sections  154 ,  156 , respectively, of the base plate lie near and substantially parallel to a bottom surface of the chute  92  and a bottom surface of the housing  30  of the machine  10 , respectively. The bottom surface of the base plate defines a holding surface which holds the central portion of the paper at a predetermined distance from the chute&#39;s bottom wall as the lateral portions of the paper turn inwardly and crumple. This distance is different than and generally less than the distance that the central portions of the paper would travel in the absence of the base plate and minimizes crumpling in the central portion of the paper. By minimizing crumpling of the central portion of the paper, the base plate facilitates the formation of a better and more uniform connection by the feed assembly  22  between the layers of paper in the central region of the formed strip. 
     The illustrated former  90  also includes a guard plate  160  mounted above the bottom leg portions  142 ,  146 ,  150  of the ribs  130 ,  132 ,  134 , respectively. The guard plate extends slightly upward inside the side leg portions  140 ,  144 ,  148  of the ribs  130 ,  132 ,  134 , respectively, laterally outwardly of the base plate  152  and longitudinally from the upstream rib  130  to the downstream rib  134 . The guard plate minimizes the extent to which the paper moves into the spaces between the longitudinally spaced ribs. Thus, the guard plate provides relatively shallow crumpling compared to crumpling from relatively unrestricted movement of the paper into the spaces between prior art ribs, thereby further minimizing the opportunity for the paper to catch between the bottom rib portions and the base plate and/or to create a sudden increase in tension as the crumpled paper passes over a rib, either of which may cause tearing or misalignment of the paper. 
     In operation, as the paper travels through the turning space of the chute  92 , the converging surfaces  100  of the chute form an outer boundary and radially restrict the paper while portions of the former  90  define a turning perimeter around which the lateral portions of the paper are inwardly turned. The relatively wide upstream end  106  of the former (the upstream rib  130 ) helps to support and guide the plies of paper into the chute. The inclined ribs  130 ,  132 ,  134  act as stabilizers to reduce misalignment of the paper in the forming assembly  20 . The inclined ribs also perform as temporary dams upstream of which the paper crumples on alternate lateral sides of the former before progressing past the ribs. Folds and creases form in the paper generally parallel to each rib as the paper crumples in the space upstream of each rib, and the memory of the paper maintains the general shape of these creases and folds that make up the crumpled portions or regions as the paper moves downstream and over alternate lateral sides of each rib. More particularly, a crumpled region of paper progresses past one lateral side of a rib while a laterally opposite portion of the paper dams and crumples behind the other lateral side of the rib. The process continues in this fashion on alternate sides of the rib, forming a herringbone pattern of crumpled regions in the stock material which increase the “height” or “fluff” of the lateral pillow portions of the resulting cushioning product. Crumpling is minimized under the base plate  152 , while the paper crumples to a greater extent in the vicinity of the guard plate  160  in the central portions of the paper adjacent the base plate, but to a lesser extent than lateral portions of the paper in the vicinity of the lateral side leg portions  140 ,  144 ,  148  of the ribs  130 ,  132 ,  134 , respectively. The inclined nature of the ribs is believed to facilitate the crumpling process as well as to facilitate the crumpled paper&#39;s progression downstream over each rib without catching on a rib or suddenly increasing the tension in the paper and causing misalignment or tearing of the paper. 
     As the paper moves over the former  90 , the mandrel portions  114  induce and perpetuate edge curl in the lateral portions of the paper. The mandrel portions also begin to internally shape the strip of paper prior to it emerging from the outlet  98  of the chute  92 . During this pre-outlet shaping, the upstream mandrel sections  116  play the dominant shaping role, the mandrel portions being shaped to increase the lateral transverse dimension (i.e., width) and the non-lateral transverse dimension (i.e., height) of the cross-sectional geometry of the strip. 
     The upstream end  106  of the former  90  supports and directs the outermost edges of the paper and the converging leg portions  112  of the top portion  110  provide support to lateral portions of the paper as it travels to the downstream end  108  of the former where the mandrel portions  114  induce edge curl and internally expand the crumpled pillow portions of the strip. The inclined lateral ribs  130 ,  132 ,  134  act as stabilizers to reduce misalignment of the paper and also perform as temporary dams whereby friction between the paper and the ribs leads to the formation of crumpled folds generally parallel to and upstream of each rib. As the paper progresses through the forming assembly  20  and is pulled over alternate lateral sides of each rib the crumpled folds formed upstream of the rib remain substantially crumpled, thereby forming a herringbone pattern of crumpled regions in the strip. 
     As the formed strip exits the chute  92 , it passes through the pad width adjustment device  94 . The pad width adjustment device provides for selective adjustment of the cross-sectional geometry of a cushioning pad formed by the machine  10 , particularly the width of the strip of cushioning, without the replacement of forming assembly  20  components. The pad width adjustment device shown in FIGS. 1-2 includes a pair of guide members  170  mounted to frame  28  of the machine  10  between the outlet  98  of the converging chute  92  and the feed assembly  22 . Thus, the device may be viewed as forming an extension of the converging chute. 
     The guide members  170  in the illustrated embodiment have a smooth cylindrical shape with an axial dimension approximately equal to the height of the outlet  98  of the chute  92 , and are positioned so that their lower axial ends are adjacent to a guide tray  172  which forms part of the frame  28  that supports the chute. The guide members have an axially extending core through which mounting components extend to non-rotatably support the guide members. The cores are eccentrically (i.e. non-centrally) located on each of the guide members to allow selective adjustment of the spacing or distance between the cylindrical surfaces of the guide members. 
     When the guide members  170  are positioned so that the shortest distance between the outer circumference of the guide members is a distance approximately equal to the width of the outlet  98  of the converging chute  92 , the guide members will guide the strip emerging from the chute in a non-converging path as it passes therebetween. Thus, the width of the pad will be the same as if the machine  10  did not include the pad width adjustment device  94 . When the guide members are positioned so that the shortest distance between the outer circumference of the guide members is decreased to less than the width of the outlet of the converging chute, the guide members guide the strip and compress it into a narrower form thereby resulting in a narrower pad. The guide members may include locking members to lock them in the selected positions. For further information about these and other types of guide members, U.S. application Ser. No. 09/189,551 filed on Nov. 11, 1998 is hereby incorporated by reference in its entirety. This application is commonly owned by the assignee of the present invention. 
     An alternative embodiment of the pad width adjustment device  94  described above is shown in FIGS. 7-9. In the illustrated embodiment the machine  200  is substantially identical to the machine  10  described with reference to FIGS. 1-6 with common parts being referred to by common reference numbers. The alternative pad width adjustment device  202  lacks the guide members  170  described above and instead includes a deflection bracket or “nose”  204  mounted to an upper portion of the converging chute  92  adjacent the outlet  98 . The deflection bracket  204  extends downward and downstream from the top of the chute. Without the lateral restriction of the guide members and with the non-lateral transverse restriction of the deflection bracket, the non-lateral transverse dimension (i.e, height) of a path of the paper downstream of the outlet is reduced such that the deflection bracket deflects an upper surface of the formed strip exiting the chute. In response, the lateral transverse dimension (i.e., width) of the strip increases, thereby providing for the production of a pad with a greater lateral transverse dimension (i.e., a substantially wider pad). Although described within the context of the illustrated machine, either embodiment of the pad width adjustment device also may be used with a prior art machine to adjust the width of the resulting cushioning product. 
     In either of the above embodiments (FIGS.  1 - 9 ), as the strip passes the pad width adjustment device  94  and/or  202 , it is guided to the feed assembly  22  which includes rotating feed members  210 ,  212  between which the paper travels. For example the feed members may include a loosely meshed idler gear  212  and drive gear  210 . When the gears are turned in the appropriate direction, the central band of the strip is engaged by the gear teeth and pulled downstream through the nip of the gears. This same “engaging” motion caused by the meshing teeth on the opposed gears simultaneously compresses or “coins” the layers of paper in the central band together thereby mechanically interconnecting the layers of material in the central band and forming the connected strip. The connection may be enhanced by stitching gears which perforate and “stitch” the layers of paper together. For further information about these and other types of feed members, U.S. application Ser. No. 08/607,607 filed on Feb. 27, 1996 is hereby incorporated by reference in its entirety. This application is commonly owned by the assignee of the present invention. Reference also may be had to other applications and/or patents incorporated herein by reference. 
     Discrete cushioning products or pads of the desired length are then severed from the connected strip by the severing assembly  24 . The severing assembly may be of any suitable type, such as the types disclosed in U.S. Pat. No. 5,123,889, U.S. patent application Ser. No. 08/110,349 and/or U.S. Pat. No. 5,569,146. (These patents and this application are commonly owned by the assignee of the present invention and their entire disclosures are hereby incorporated by reference.) However whatever type of severing assembly is used, the connected strip is divided into cut sections or pads of the desired length and these cut sections travel downstream to the post-severing assembly  28 . A cut section emerging from the post-severing assembly may be directed to a desired packaging location. The conversion of paper into pads of relatively low density cushioning dunnage is now complete, the conversion process having been improved as described in the above paragraphs. 
     Although the invention has been shown and described with respect to certain illustrated embodiments, equivalent alterations and modifications will occur to others skilled in the art upon reading and understanding the specification and the annexed drawings. In particular regard to the various functions performed by the above described integers (components, assemblies, devices, compositions, etc.), the terms (including a reference to a “means”) used to describe such integers are intended to correspond, unless otherwise indicated, to any integer which performs the specified function (i.e., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated embodiments of the invention. In addition, while a particular feature of the invention may have been described above with respect to only one of several illustrated embodiments, such a feature may be combined with one or more other features of the other embodiment, as maybe desired and advantageous for any given or particular application.