Abstract:
A method for making a composite structural member. The composite structural member has a flange having a base wall and two side walls extending from the base wall, the base wall and side walls forming a pocket to receive a portion of a web. Each side wall of the flange is doubled with an inner wall panel and an outer wall panel joined along a fold line spaced from, and parallel to, the base wall. Fasteners are formed from each side wall adjacent the fold line, each fastener having inner and outer wall panel sections joined by a section of the fold line and extending transversely from its side wall toward the other side wall. The flange is used with the web, a portion of the web mounted in the pocket with the side walls of the flange adjacent the sides of the web and the fasteners pressed into the sides of the web to secure the flange to the web. The method comprises the steps of: mounting the web within the pocket of the flange to form an elongated assembled unit; moving the unit longitudinally; forming the fasteners in the side walls while the side walls diverge from the web and the unit moves; and then moving the side walls against the web to press the fasteners into the web while the unit moves to secure the flange to the web.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
   This application is a divisional application of application Ser. No. 09/561,922, filed May 1, 2000 now U.S. Pat. No. 6,457,292. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   This invention is directed toward a method for making the composite structural member employing a flange member. 
   The invention is further directed toward an apparatus for use in making the composite structural member. 
   2. Description of the Related Art 
   Composite structural members, such as I-beams, are known. These composite structural members usually have separate flanges joined to a central web in making beams, particularly I-beams. The materials usually employed, in both the flanges and webs, are wood; wood-based, engineered products such as plywood; and metal such as steel. Composite structural members employing metal flanges with a wooden web are efficient and cost-effective. The wooden web provides a desirable insulation factor, compared to a metal web and allows openings to be easily made through it for services. The metal flanges provide high strength and stability for the member. In addition the metal flanges can be provided with integral fasteners formed by punching teeth out of the flanges. The teeth can be easily pressed into the web to securely join the flanges to the web. 
   One form of a composite structural member employing a wood-based web and metal flanges is shown in U.S. Pat. No. 4,281,497. Each metal flange member is formed with side walls extending from a base. Fasteners are usually formed integrally in the side walls of the flange. An edge of the web is located against the base and the side walls of the flange, with the fasteners formed therein, are bent about the base against the web to form a pocket to receive an edge portion of the web. At the same time the fasteners in the side walls are pressed into the web to fasten the flange to the web. In this construction, the fasteners are formed in the flange, in a separate operation, before the flange and web are assembled. This additional step makes the assembling of the composite member relatively expensive. 
   It is preferred to have the side walls of the flange member doubled so as to have the pocket formed by side walls and base of the flange, which pocket receives an edge portion of the web, more rigid and thus more likely to tightly confine the web making the bearing capacity of the web stronger and thus making the composite member stronger. An example of such a construction is shown in U.S. Pat. No. 4,937,998. However, using metal flange members, with doubled side walls, with a wooden web, and with integral fasteners in the doubled side walls, is expensive. Openings must be provided in the inner wall panel of the doubled side wall to allow passage of the integral fasteners formed in the outer panel of the doubled side wall. The integral fasteners, and the openings for the fasteners, are formed in the flange in a separate operation, before assembly of the flange and web, again making the assembly relatively expensive. 
   Both types of composite members described above have the fasteners, joining the flange to the web, integrally formed in the flange in a single layer of sheet metal. The sheet metal layer must therefore be relatively thick to provide fasteners strong enough to penetrate the web. Using relatively thick sheet metal flanges, which may be thicker than the thickness required to provide the necessary strength for the composite member, increases the cost of the members. 
   SUMMARY OF THE INVENTION 
   It is the purpose of the present invention to provide a method of assembling a flange to a web in the making of a composite structural member, which method involves the step of forming integral fasteners in the side walls of the flange while assembling the flange to the web. 
   It is a further purpose of the present invention to provide a machine for assembling a flange to a web in the construction of a composite structural member. The machine forms fasteners in the side walls of a flange while moving the flange and web together as a unit, the fasteners then being used to connect the flange to the web. 
   The invention is particularly directed toward a method of making a composite structural member comprising providing an elongated metal flange having a pocket, the pocket formed by two side walls extending from a base wall; and an elongated web, made of fastener penetrable material, having opposed narrow edges. A portion of the web is mounted within the pocket of the flange with one edge abutting the base wall to form an assembled unit. The assembled unit is then fed in a longitudinal direction. Fasteners are then formed from the side walls of the flange while the side walls diverge from the web. The side walls are then moved against the web to press the fasteners into the web to securely join the flange to the web. 
   In a preferred embodiment, the side walls of the flange are doubled, each side wall has inner and outer wall panels, the wall panels joined along a fold line spaced from the base wall. The fasteners are integrally formed in the side walls adjacent the fold line, punched out along a line that intersects the fold line, and then bent laterally from the side wall. 
   The invention is further particularly directed toward a machine for use in making a composite structural member from an elongate web made from fastener penetrable material, the web having opposed narrow edges, and an elongate metal flange having side walls and a base wall joining the side walls to form a pocket for receiving a portion of the web. The machine has an elongated support table for supporting an assembled unit, comprising the flange with the web therein, for movement in the longitudinal direction of the unit. The machine has drive means on the table for moving the unit in the longitudinal direction. Forming means are on the table to form fasteners in the side walls of the flange while the side walls diverge from the web. Pressing means are on the table, downstream from the forming means, for moving the side walls of the flange against the web to cause the fasteners, integrally formed in the side walls, to enter the web and join the flange to the web as the unit is moved forwardly. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a web and one type of flange used in the making of a composite structural member; 
       FIG. 2  is a perspective view of the web and flange assembled to provide the composite structural member; 
       FIG. 3  is a cross-section view showing the side walls of the flange spread apart from the web; 
       FIG. 4  is a cross-section view showing the fasteners formed in the spread-apart side walls; 
       FIG. 5  is a cross-section view showing the web and flange assembled to form the composite structural member; 
       FIG. 6  is a perspective view of a preferred flange used in the making of the composite structural member; 
       FIG. 7  is an end view showing the side walls of the preferred flange spread-apart with fasteners formed therein; 
       FIG. 8  is a partial perspective view of a section of side wall showing the formation of the fasteners: 
       FIG. 9  is a cross-section view taken along line  9 — 9  in FIG.  8 . 
       FIG. 10  is a detail plan view of another fastening tooth; 
       FIG. 11  is an end view of another embodiment of a flange; 
       FIG. 12  is a partial perspective view of a panel used to make the flange shown in  FIG. 1 ; 
       FIG. 13  is a partial perspective view of a panel used to make the preferred flange shown in  FIG. 6 ; 
       FIG. 14  is an end view of another partially formed flange; 
       FIG. 15  is a side view of an apparatus used to make the composite structural member; 
       FIG. 16  is a cross section view taken along line  16 — 16  in  FIG. 15 ; 
       FIG. 17  is a detail plan view of a portion of the apparatus showing the forming station; 
       FIG. 18  is a detail plan view of another portion of the apparatus showing the press station; 
       FIG. 19  is a detail plan view of another embodiment of the forming element; and 
       FIG. 20  is a detail plan view showing the spreading station. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The flange  1  used in the present invention has a base wall  3  with a pair of side walls  5 ,  5  extending laterally from the base wall  3  as shown in FIG.  1 . The side walls  5  each have inner and outer edges  7 ,  9 , with the inner edges  9  joined to the base wall  3 . The base  3  and side walls  5 ,  5  form a pocket  11  for receiving a web  13 . The web  13  has narrow, opposed, edges  15 ,  17  and wide parallel, sides  19 ,  21  joined the edges  15 ,  17 . Both the flange  1  and web  13  are elongated structures with the flange  1  being made from suitable metal material, such as steel sheet or aluminum by way of example. The web  13  is made from suitable, fastener-penetrable material, such as wood or a wood based, engineered product. The web can, for example, be made from plywood or OSB (Oriented Strand Board). Or the web can be made from a mixture of wood particles and suitable plastic material pressed or molded together. 
   The web  13  is assembled with the flange  1  by inserting an edge portion of the web into the pocket  11  of the flange  1  so that one edge  15  of the web abuts the base wall  3 , and the side walls  5 ,  5  of the flange  1  are adjacent the sides  19 ,  21  of the web  13 , as shown in FIG.  2 . The assembled unit  23  is then fed forward longitudinally as shown by the arrow  25  in FIG.  2 . As the unit  23  is fed forwardly, the side walls  5 ,  5  of the flange  1  are spread apart from the web  13  as shown by the arrows  27  in FIG.  3  and fasteners  31  are then formed from the side walls  5 ,  5  as shown in FIG.  4 . The fasteners  31  are preferably punched out of the side walls and bent inwardly toward the web  13 , the fasteners  31  being triangular shaped and pointed. The side walls  5 ,  5  are spread apart a sufficient distance from the web  13  to allow room for the formation of the fasteners  31 . The fasteners  31  are normally formed near the outer edge  7  of the side walls  5 ,  5 . The fasteners  31  can be formed during the forward movement of the unit  23  or the unit  23  can be moved forwardly intermittently and the fasteners  31  formed during stoppage in movement of the unit. Once the fasteners  31  have been formed, the side walls  5 ,  5  are moved back against the sides  19 ,  21  of the web  13  with the fasteners  31  being pressed into the web  13  to securely join the flange  1  to the web  13  to form a composite structural member  33  as shown in FIG.  5 . 
   The flange  1  may be provided from the factory with the side walls  5 ,  5  already spread-apart, as shown in  FIG. 3 , instead of with the side walls  5 ,  5  parallel, or nearly so, as shown in FIG.  2 . When the flange  1 , with the spread-apart side walls  5 ,  5 , is assembled with the web  13 , the unit  23  is moved forwardly to form the fasteners  31  in the already spread-apart side walls  5 ,  5  of the flange  1 . 
   The flange may be assembled to the web at the factory where the flange is formed to shape, or at a building site. If the assembling occurs at the building site, the flanges, since they do not yet have the fasteners formed therein, can be compactly stacked and thus less expensively shipped from the factory to the building site. 
   In a preferred use, the flange has doubled side walls, and the fasteners are formed in the outer edge of the side walls. As shown in  FIG. 6 , the preferred flange  101  has a base wall  103  and side walls  105 ,  105 , as before. Each side wall has an outer edge  107  and an inner edge  109 , the inner edges  109  joined to the base wall  103 . The base wall  103  and the side walls  105 ,  105  form a pocket  111  for receiving the web  13 . Each side wall  105 ,  105  has an inner wall panel  113  and an outer wall panel  115 . The inner edge of the inner wall panel  113  is joined to the base wall  103  by a fold line forming inner edge  109 . The outer edge of the inner wall panel  113  is joined to the outer edge of the outer wall panel  115  by a fold line forming the outer edge  107  of the side wall  105 . 
   The flange  103  and the web  13  are assembled, as before, into a unit  123  which is fed forwardly longitudinally. As the assembled unit  123  is fed forwardly, the side walls  105 ,  105  of the flange  103  are spread apart from the web  13  and fasteners  131  are integrally formed from each side wall as shown in FIG.  7 . The fasteners  131  are preferably formed by cutting the side wall  105  along a line  133  that angles to, and intersects, the fold line  107  as shown in FIG.  8 . The cut can be made by punching the side wall with a punch. The triangular shaped tooth  131 , formed by the cut, is then bent inwardly from the plane of the side wall  105  toward the web  13 . The tooth  131  has wall sections  135 ,  137 , formed from the inner and outer wall panels  113 ,  115  respectively, as shown in  FIG. 9 , and joined by a section  139  of the fold line  107 . The tooth  131  is very strong, being double-walled. Once the teeth  131  have been formed, the side walls  105 ,  105  are moved back against the sides of the web  113 , the teeth  131  simultaneously pressed into the web  13  to securely join the flange  101  to the web  13 . 
   The fasteners  131  on one side wall preferably alternate, in a longitudinal direction, with the fasteners on the other side wall. The fasteners  131  have been shown as being triangular in shape, but they could have other shapes as well. For example, the fasteners  131 ′, as shown in  FIG. 10 , could have a rectangular shaped main body  141  with a pointed free end portion  143  extending from one short side of the main body  141 . The inner end of the main body portion is preferably rounded toward the outer edge, as shown at  145  in  FIG. 10 , to minimize tearing of the wall panels in this area. Similar rounding could be employed at the base of the triangular shaped tooth  131  as shown in FIG.  8 . 
   The flange  101  shown in  FIG. 6  is particularly suited for making flanges that can be used to make I-beam composite members. The I-beam flanges have wing panels  147  extending laterally from the bottom edge of the outer wall panels  115  of the side walls  105 , the wing panels  147  aligned with each other and with the base wall  103 . The wing panels  147  are joined to the outer wall panels  115  along a fold line  149 . A narrow stiffening panel  151  can extend laterally from the free end of each wing panel  147 , the stiffening panel  149  parallel to the side wall panels  115  and joined to the wing panels  147  along a fold line  153 . 
   While one form of flange  101 , with single wing panels  147  and doubled side walls  105 , has been described, other forms of flanges can be employed. For example, the flange  101 ′ can have doubled side walls  205 ,  205  and doubled wing panels  247 ,  247  as shown in FIG.  11 . 
   The flanges can be easily, partly formed off-site, without the fasteners formed therein, and then shipped to the site for making composite structural members. The flange  1 , for example, can be formed by bending an elongate panel  201 , as shown in  FIG. 12 , along fold lines  203 ,  205  to form base wall  3  and side walls  5 ,  5 . The fold lines  203 ,  205  define the bottom edge  9  if the side walls  5 ,  5 . Lines  207  of incisions  209  can be provided in the panel  201  adjacent each fold line  203 ,  205  location, before folding, so as to facilitate folding. The incisions  209  can be right at the fold or just on either side of it. The flanges can be folded to have the side walls  5 ,  5  generally parallel, as shown in  FIG. 1 , or to have the side walls  5 ,  5  diverging slightly, as shown in FIG.  3 . The folded flanges  1 , in either form, can be easily nested and efficiently shipped to the work site. 
   The flange  101  can be formed from a single panel  211 , as shown in  FIG. 13 , bent along fold lines  109  to form the base wall  103  and side walls  105 ,  105 . Each side wall  105  has inner and outer panels  113 ,  115 , the panels joined by fold lines  107 . The wing panels  147  are joined to the bottom of the outer panels  115  by fold lines  149 . Lines of incisions, not shown, can be used to facilitate folding along the fold lines. 
   The flanges  101 , with the wing panels  147 , could be partly folded off-site to produce the article  301  shown in FIG.  14 . In this article, the doubled side walls  105 ,  105  have not been folded up from the base wall  103  and the article  301  is flattened to make shipping easier. At the work site, the side walls  105 ,  105  are partly folded up toward the web, the fasteners formed, and the composite structural member completed by completing folding of the side walls against the sides of the web. 
   An apparatus is provided for making the composite structural member described. The apparatus  401 , as shown in  FIGS. 15 and 16 , has an elongated, work table  403  maintained in a horizontal position by legs  404 . Feeding means  405  are provided on the work table  403  for feeding the assembled unit  123  of the flange  101 , with diverging side walls, and the web  113 , in a longitudinal direction on the work support. The feeding means  405  can comprise sets  407  of side drive rollers  409 , the sets spaced along the length of the feed path. There is a drive roller  409  in each set on each side of the web  113 , the drive rollers contacting the web to feed it forwardly. The axis of these side rollers  409  is parallel to the sides of the web  113 , the rollers  409  located above the flange  101  to be able to contact the web. The side drive rollers  409  are driven by suitable motor means  410 . The feeding means  405  can also include top, drive rollers  411  biased against the top edge of the web  113 , and driven by suitable motor means  412 , to feed it forwardly. The assembled unit  123  rides on support rollers  413 , mounted for free rotation in openings in the table  403 . If desired, some of the guide rollers  413  could also be driven by suitable motor means, not shown. Guide roller sets  415 , similar to the drive roller sets  407 , but with guide rollers  409 ′,  411 ′ instead of drive rollers, could also be provided on the table  403  along the feed path for guiding the assembled unit  123  during its movement along the table in a longitudinal direction on the support rollers. 
   The apparatus includes a first forming station  421 , as shown in  FIGS. 15 and 17 , where the fastening means on each side wall of the flange are formed. Fastener forming means  423  are provided at the forming station  421 , one on each side of the path of travel of the assembled unit to form fasteners from the side walls of the flange. The forming means  423  can include a punch  425  that is located above the table, by a support  426  at a height to partially punch out a fastener  131  out of the side wall. The punch  425  preferably is adjustable in height on the on the table and preferably is located to punch out the fastener adjacent the outer edge of the side wall of the flange. The punch  425  is operated by a hydraulic cylinder  427  or other suitable operating means and has a cutting edge  429  for cutting the side wall along the desired line to define the fastener. Continued forward movement of the punch after cutting bends the fastener out of the plane of the side wall. The forming station  421  includes an anvil plate  431  on each side of the unit, the plate  431  on each side supported by a support arm  433  on the table  403 . The anvil plate  431  is located between the side wall  105  and the web  113 , just in front of the punch  425 , and supports the side wall  105  during punching of the fastener  131 . A portion of the anvil plate  431  can extend forwardly of the punch  425 , beneath the punch, if desired, to provide additional support for the sidewall. 
   Once the fasteners  131  have been formed on each side wall at the forming station  421 , continued movement of the assembled unit  123  brings it to a press station  441  as shown in  FIGS. 15 and 18 . The press station  441  can comprise sets  443  of press rolls  445  on each side of the unit which are sized, shaped and positioned to gradually move the spread-apart side walls  105 ,  105  of the flange  101  against the web  113  while pressing the fasteners  131  into the web  113  to securely fasten the flange  101  to the web  113 . The press rolls  445  are supported by supports  447  on the table  403 . 
   While the assembled unit  123  is fed to the forming station  421 , the side walls  105 ,  105 , diverging from the web  113 , provide a space  451  between the side walls and the web for the anvil  431  on each side. The punch  425  is periodically operated to punch a fastener out of the side wall just after it leaves the anvil so the side wall is partly supported while the fastener is being formed. The assembled unit can be moving while the punch is actuated. Alternatively, the unit can be periodically stopped to allow the punch to operate while the unit is stationary. 
   In one embodiment, the forming station  421  can have a gang of punches  451  mounted on a support plate  453  which support plate is movable by suitable moving means, not shown, to have the gang of punches simultaneously punch a set of fasteners out of the side walls. In this embodiment, the assembled unit is stopped and moved intermittently. The press rollers  445  on each side of the unit at the press station  441  could also be replaced by an elongated press pad, not shown, moved inwardly to press the side walls, and the fasteners, against the web. The press pad would operate at the same time that the gang of punches  451  are operated while movement of the unit is stopped. 
   The machine preferably includes a diverging station  461  in front of the forming station  421 . The diverging station  461  spreads the side walls  105 ,  105  of the flange  101  in the assembled unit  123  apart from the web  113 , if the flange is provided with parallel side walls from the factory. The diverging station  461  has tapered guide plates  463  located between the web and the side walls, one face  465  of the plate  463  on each side flat against the side of the web, the other face  467  angled outwardly to move the side walls away from the web and to thus provide the space  451  for the anvils  431  at the forming station  421 . The guide plates  463  are carried by support means  471  fastened to the table  403 . 
   Suitable, programmable, control means can be provided to operate the machine to form the fasteners at the desired locations in the flange. While the apparatus has been shown fastening flange  101  to web  113  it can also be used to fasten flange  1  to web  13 . 
   The method of making the composite structural member is relatively inexpensive since the folding of the material, to form the flanges, can be done offsite at high speed and thus very efficiently. The forming of the fasteners, which is slower, takes place on-site during the assembly of the composite structural unit. It will be seen that the fasteners are formed during assembly of the flange to the web so that a separate fastening forming step, with attendant handling of the flange, is eliminated, thus leading to further efficiencies and less expense. 
   The flanges with doubled side walls provide very strong fastening members since the fastening members formed from the side walls are also doubled walled and joined together. The double walled side walls also make the flange stronger; allows the use of thinner sheet material; and retains the shape of the pocket better thus forming a stronger connection between the web and the flange and making for a stronger composite structural unit. 
   It is to be understood that while only one flange has been described as being attached to the web to form the structural unit, a second flange is usually attached to the other edge portion of the web, in a similar manner, but in a second operation, to form a balanced structural member such as an I-beam.