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BACKGROUND OF THE INVENTION  
       [0001]     This invention relates to material handlers, and in particular to material handlers for use by self-propelled machines to handle elongate panels of sheet material.  
         [0002]     In the roofing industry, as well as other industries, it is common to use elongate panels of sheet material at elevated heights. For example, many industrial and commercial buildings have roofs constructed of corrugated roofing panels. These panels, which are commonly made from steel, aluminum, or copper, can be made into any shape and size to accommodate the dimensions and configuration of the roof. Typically, roofing panels are made relatively large to reduce the number of panels that need to manufactured, purchased, transported, and installed. As a result, it is common for metal roofing panels to have widths ranging from about 2 feet to about 4 feet and length ranging from about 3 feet and about 50 feet. It is also common for each panel to weigh between about 1 pound and about 3 pounds per square foot. By way of example, a panel being 3 foot wide by 20 foot long and weighing 2 pounds per square foot would weigh about 120 pounds.  
         [0003]     Commonly, roofing panels are packaged during the manufacturing process in bundled stacks containing numerous panels. As can be appreciated, these bundles weigh a considerable amount. Accordingly, machinery (e.g., forklifts, trucks), is typically used to move the bundle of panels from the manufacturer to any intermediate locations (i.e., warehouse, retail store) and finally to a job site, were the panels can be used. At the job site, the bundle (or numerous bundles) of panels is typically placed on the ground. Individual panels are then separated from the bundle and manually transported to the roof of the building were they can be secured to framing members (e.g., roof trusses) of the building. Manually transporting each panel to the roof is both time consuming and labor intensive because of the weight and size of each panel, and the height to which the panel needs to be transported.  
       SUMMARY OF THE INVENTION  
       [0004]     A material handler of the present invention is for use by a self-propelled machine to handle elongate panels of sheet material. The material handler generally comprises a support adapted to receive and support the elongate panels. A base mounts the support for pivotal movement of the support relative to the base about a tilt axis which is transverse to the length of the elongate panels when held on the support. The base is adapted for connection to the self-propelled machine. A mover drives the pivotal movement of the support relative to the base to selectively tilt the support about the tilt axis so that when the elongate sheets are held by the support, the elongate sheets assume a desired slope along their lengths.  
         [0005]     Another aspect of the present invention is a method of sheathing a pitched roof on a structure using elongate panels of sheet material having a length and a width. The method generally comprises loading a plurality of elongate sheet material panels onto a support. The panels lie in a stack on the support. The method also includes raising the support to a height corresponding to that of the pitched roof to be sheathed, and tilting the support to an angle such that the sheet material panels held by the support are inclined along their lengths. In addition, the method includes sliding sheet material panels lengthwise from the stack on the tilted support onto the structure and securing them to the structure for sheathing the pitched roof.  
         [0006]     In yet another aspect of the present invention, a material handler can be used by a self-propelled machine to handle elongate panels of sheet material. Each elongate sheet has a length and a width. The material handler generally comprises a base adapted for connection to the self-propelled machine and a support adapted to receive and support the elongate panels. The support is adjustable relative to the base in a direction to accommodate elongate panels of different widths.  
         [0007]     Other objects and features of the present invention will be in part apparent and in part pointed out hereinafter. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]      FIG. 1  is a perspective illustrating a material handler of the present invention attached to a telehandler and used to support elongate roofing panels adjacent a building under construction;  
         [0009]      FIG. 2  is a perspective of the material handler;  
         [0010]      FIG. 3  is a top plan view of the material handler;  
         [0011]      FIG. 4  is a side elevation of the material handler with a portion of a beam cut away;  
         [0012]      FIG. 5  is a section of the material handler taken along line  5 - 5  of  FIG. 4 ;  
         [0013]      FIG. 6  is an end view of the material handler;  
         [0014]      FIG. 7  is a perspective of the material handler showing a support disconnected from a base;  
         [0015]      FIG. 8  is a perspective of the material handler showing support arms in a fully extended position;  
         [0016]      FIG. 9  is a perspective of the material handler showing two telescopic beams fully extended and tilted; and  
         [0017]      FIG. 10  is a perspective of the material handler showing the two telescopic beams fully extended and in a generally horizontal position. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0018]     Referring now to the drawings and in particular to  FIG. 1 , a material handler of the present invention is indicated generally at  1 . As illustrated, the handler  1  is connected to a telehandler T (broadly, “self-propelled machine”) and holds a stack of corrugated roofing panels P. A telehandler is a type of forklift having an extensible boom. As a result, the telehandler T can be used to lift the panels P supported by the material handler  1  to adjacent a roof (generally indicated at R) of a building B under construction. The material handler  1  can pivot about a tilt axis TA ( FIG. 2 ) transverse to the length of the elongate panels P to position the roofing panels at an angle matching the pitch of the roof R. The pitch of roof R is the amount of vertical rise in the roof per horizontal run, which can also be expressed as an angle a formed between the roof R and a horizontal plane which intersects the apex of the roof. The roofing panels P then can be removed from the material handler  1  as needed, and secured to the roof R in the desired location. Thus, a considerable amount of time and labor costs are saved as compared to manually transporting the roofing panels P one at a time to roof level, as is commonly done. It is understood that the material handler  1  can be used with other types of elongated panels of sheet material besides roofing materials without departing from the scope of this invention. It is further understood that the self-propelled machine could be a forklift or even some other machine that does not perform a lifting function without departing from the scope of the present invention. It is also envisioned that the material handler  1  could be attached to supporting structure that is not self-propelled.  
         [0019]     As shown in  FIGS. 2 and 7 , the material handler  1  comprises a support, generally indicated at  3 , and a base, generally indicated at  5 , mounting the support. The support  3  comprises two telescopic beams, which are indicated at  7 , and eight, spaced-apart support arms  9  attached to the beams for receiving and supporting roofing panels. The two telescopic beams  7  extend generally parallel to a longitudinal axis LA of the material handler  1  and in opposite directions. Each beam  7  comprises a series of (i.e., four) beam elements  11 A- 11 D formed from structural tubing having progressively smaller cross sections so that the beam elements with smaller cross sections can be telescopically received in the beam elements with larger cross sections ( FIGS. 5 and 6 ). Each of the beam elements  11 A- 11 D are adapted for selective positioning between a retracted position ( FIG. 2 ), in which the smaller beam element is substantially received within the adjacent larger beam element, and an extended position ( FIG. 10 ), in which the smaller beam element is extended from the adjacent larger beam element. In the illustrated embodiment, the length of the support  3  extends from approximately 8 feet when all of the beam elements  11 A- 11 D are fully retracted to approximately 43 feet when the beam elements are fully extended. The dimensions of the support  3  are provided for exemplary purposes only and can be different from those listed herein. It is understood that the material handler  1  could comprise a single beam  7  or more beams without departing from the scope of this invention. It is also understood that the beams  7  could have more or fewer beam elements  11 A- 11 D.  
         [0020]     As shown in  FIG. 5 , each telescopic beam  7  comprises four beam elements  11 A- 11 D, each with a different cross sectional area. Three of the beam elements  11 B- 11 D are telescopically received in the other, larger beam elements  11 A. As illustrated in  FIGS. 9 and 10 , the three, telescopically received beam elements  11 B- 11 D have a plurality of holes  13  located at spaced intervals generally along the lengths of the beam elements. The beam elements  11 A with the larger cross sections have a single hole  13 . To secure the beam elements  11 A- 11 D at the desired length, the holes  13  of adjacent beam elements are aligned and pins  15  are inserted therethrough. As illustrated in  FIG. 2 , the holes  13  in the beam elements  11 A- 11 B can be aligned so that in the retracted position a single pin  15  can be used to secure all of the beam elements of a single beam  7 . To extend the length of the beam  7 , the pin  15  is removed and the beam elements  11 A- 11 D with smaller cross sections can be slid in a longitudinal direction to the desired length. As illustrated in  FIG. 9 , three pins  15  can be used to fix adjacent beam elements  11 A- 11 D of a single beam  7  together in a fully extended position. Since the beam elements with smaller cross sections have a plurality of holes, the length of the support  3  can also be extended to positions between the fully extended position and the fully retracted position to accommodate panels of sheeting material having different lengths. It is understood that the beam elements  11 A- 11 D may include more or fewer holes  13  to vary the possible longitudinal lengths to which the beams  7  can be extended.  
         [0021]     Referring to  FIGS. 4 and 5 , sleeves, which are make of nylon, are used to centrally maintain the portions of the beam elements  11 B- 11 D having smaller cross sections with respect to the beam elements having larger cross sections in which they are received. The sleeves comprise a first sleeve section  67 , which is attached to the inside surface of one of the beam element  11 A- 11 C that receives a smaller beam element, and a second sleeve section  69  is attached to the outside surface of the smaller beam element  11 B- 11 D. Both of the sleeve sections  67 ,  69  are attached adjacent the end of the respective beam element  11 A- 11 D such that when the beam elements are in a retracted position as illustrated in  FIG. 5 , the sleeve sections are spaced from each other to adequately support the smaller beam element at both ends.  FIG. 4  shows a portion of the largest beam element  11 A cut away to expose the first sleeve section  67  attached to the inside surface thereof, and the second sleeve section  69  attached to the outside surface of the adjacent beam element  11 B, which is received in largest beam element. In addition, the sleeves sections  67 ,  69  provide a smooth surface for sliding the beam elements  11 B- 11 D with respect to each other, and act as a stop to prevent the smaller beam element from sliding out of the larger beam element when the beam elements are moved to the extended position.  
         [0022]     As mentioned above, the support  3  also comprises a number of support arms  9 , which are attached to the longitudinally extending beams  7  by brackets  19 . As shown in  FIGS. 3 and 8 , a total of eight support arms  9  are attached to the beams  7 . Two support arms  9  are attached to the beam elements  11 A with the largest cross section and one support arm to each of the other beam elements. The support arms  9  are centered about the longitudinal axis LA of the material handler  1  to accommodate and support elongate roofing panels. Since the beams  7  are spaced from and extend generally parallel to the longitudinal axis LA of the material handler  1 , one end of the support arms  9  is spaced further from the beam  7  than the other end of the support arm to center the load over the longitudinal axis LA of the material handler  1 . The support arms collectively align to define a planer surface generally in a horizontal plane for receiving the roofing panels.  
         [0023]     As best illustrated in  FIG. 6 , the support arms  9  attached to the beam elements  11 B- 11 D with smaller cross sections have taller brackets  19  to compensate for the reduced height of the beam element so that all of the support arms lie in generally the same horizontal plane. The brackets  19 , which are generally channel shaped in cross section, are attached to the beam elements  11 B- 11 D using fasteners (i.e., bolts) and to the support arms  9  by welding.  
         [0024]     Referring to  FIG. 8 , each of the support arms  9  has a fixed central portion  23 , a forward extending portion  25 , and a rearward extending portion  27  to thereby allow the length of the arms to be selectively positioned for accommodating elongate panels of different widths. In the illustrated embodiment, the length of the support arms  9  can be selectively changed from about 28 inches ( FIG. 3 ) to about 56 inches ( FIG. 9 ). The support arms  9  are formed from tubular steel having a generally square cross section. The central portions  23  of the support arms are fixed (e.g., welded) to either the beam elements  11 A or the brackets  19 . The extending portions  25 ,  27  have slightly smaller cross sections than the fixed portions  23  such that the extending portions can be telescopically received in the fixed portion. Each of the fixed portions  23  include a hole  26  positioned adjacent each end for aligning with one of a plurality of holes  28  in the extending portions  25 ,  27  ( FIG. 8 ). The extending portions  25 ,  27  have holes positioned approximately every 2 inches along its length to provide numerous lengths at which the support arms  9  can be positioned. Pins  30  are selectively insertable into the holes  26 ,  28  after they are aligned to secure the extending portions  25 ,  27  with respect to the fixed portions  23 . In addition, each of the extending portions  25 ,  27  can be removed from the fixed portion, which may be advantageous when loading panels P onto the support  3 . It understood that the extending portions  25 ,  27  and/or the fixed portions  23  can have more or fewer holes. It is also understood that the extending portions may be selectively secured to the fixed portions  23  using devices besides pins.  
         [0025]     Each of the support arms  9  further comprises upwardly extending flanges  29  attached to each end of the support arms. The flanges  29 , which are generally rectangular shaped pieces of metal, are adapted to engage opposite side edges of the panels positioned on the support  3  to thereby prevent the panels from sliding off of the support. It is understood that the support arms  9  may be selectively positionable between lengths different from those provided herein or have a fixed length without departing from the scope of this invention. It is also understood that the support  3  could have more or fewer support arms  9  than disclosed herein.  
         [0026]     A retainer  32  is located at one end of the support  3  for holding the elongate panels, when positioned on the support in a tilted position, from sliding off of the support. The retainer is pivotally mounted on the central portion  23  of the support arm  9  for movement between a retaining position and a non-retaining position. It is understood that the support arms  9  positioned at the end of both beams  7  could have retainers. It is also understood that the retainer may be fixed in the retaining position.  
         [0027]     Referring to  FIGS. 2 and 7 , the base  5 , which underlies the support  3 , comprises a first fork tube  33  and a second fork tube  35  spaced from the first fork tube. Each of the fork tubes  33 ,  35  is made of rigid structural tubing, such as steel tubing having a generally rectangular cross section, that is sized and shaped for allowing forks (not shown) of the telehandler T to slide in and out of the fork tubes. The illustrated fork tubes  33 ,  35  are adapted for receiving forks having a width of about 4 inches and a thickness of about 1.8 inches. In addition, the fork tubes  33 ,  35  are slightly shorter than the length of the forks on the telehandler T. As a result, pins can be inserted through apertures adjacent the ends of the forks to secure the material handler  1  to the telehandler T. It is understood that the fork tubes  33 ,  35  may have other shapes and sizes to accommodate various sizes of forks. It is also understood that the material handler  1  can be attached to the telehandler T, other types of self-propelled machines, or supporting structures using other suitable attachment means besides forks.  
         [0028]     Two spacer members  37 , made of square steel tubing are welded to and span between the fork tubes  33 ,  35 . One of the spacer members  37  is aligned generally with rear edge margins of the fork tubes  33 ,  35  while another spacer member is aligned generally with the front edge margins of the fork tubes. Four frame members  39  are securely attached (i.e., by welding) to the top of the fork tubes  33 ,  35  and spacer members  37  to form a rectangular frame, indicated generally at  41 . The outwardly facing surfaces of the frame members  39  are generally coplanar with the outwardly facing surfaces of the fork tubes  33 ,  35  and the spacer members  37 . It is understood that the base  5  can have more or fewer spacer members  37 , or the fork tubes  33 ,  35  and the spacer members can be formed from as one piece.  
         [0029]     A platform, indicated generally at  43 , is pivotally mounted on the frame  41  of the base  5 . The platform  43  includes three rigid, structural tubes  45 , such as steel tubing having a square cross section. Two of the tubes  45  extend generally parallel to the longitudinal axis LA of the material handler  1  and are spaced outwardly an equidistance from the axis in a forward and a rearward direction. The other tube  45  extends between and is attached to the two parallel tubes such that the three attached tubes from a generally U-shaped structure. The platform  43  further comprises a rod  49  extending between and attached to the two parallel tubes  45 . The rod  49  is positioned adjacent the ends of the parallel tubes, spaced from the transverse tube. It is contemplated that the platform  43  can have other configurations, such as being a unitary structure or comprising more or fewer structural tubes  45 .  
         [0030]     As illustrated in  FIGS. 4 and 7 , the material handler  1  further comprises a hinge  51  and linkage, generally indicated at  53 , connecting the frame  41  of the base  5  to the platform  43 . The hinge  51 , which is located along a first side of the base  5 , forms a pivot on which the platform  43  can rotate with respect to the frame  41  of the base  5 . The hinge  51  comprises a pair of knuckles (only one is shown) welded to the frame  41  of the base  5  and a knuckle welded to the platform  43 . Each of the knuckles has an opening for receiving a hinge pin  52 .  
         [0031]     Referring now to  FIG. 7 , the linkage  53 , which is located along a second side of the base, opposite the first side, is adapted to extend and retract in conjunction with the pivotal movement of the platform  43  on the hinge  51 . The linkage  53  comprises two pairs of links. Each pair of links has an upper link  55  and a lower link  57 . The upper link  55  is pivotally mounted at one end on the rod  49  of the platform  43  and on the lower link  57  at its opposite end. The lower link  57  is pivotally mounted at its end opposite the upper link  55  on the frame  41  of the base  5 . Accordingly, the linkage  53  moves from a collapsed position when the platform  43  is positioned generally horizontal with respect to the frame  41  to a raised position ( FIG. 7 ) when the platform is tilted about the tilt axis TA.  
         [0032]     As shown in  FIG. 4 , the platform  43  is attached as by welding to the telescoping beams  7  by two tubular framing members  59 . Each of the tubular framing members are attached to both beams  7  to thereby attach the base  5  to the support  3 . Thus, movement of the platform  43  about the tilt axis TA results in the support  3  also moving about the tilt axis. A hydraulic cylinder (broadly, “a mover”), which is indicated at  61 , is used to drive the pivotal movement of the support  3  relative to the frame  41 . The hydraulic cylinder  61  includes a piston rod  65  that can extend and retract in a conventional manner. The hydraulic cylinder  61  is in fluid communication with the hydraulic system of the telehandler T via hoses (not shown). Thus, the operation of the hydraulic cylinder  61  can be controlled using controls positioned on the telehandler T, as is know in the art. The support  3  can be pivoted with respect to the frame  41  manually or using other types of driving mechanisms without departing from the scope of this invention.  
         [0033]     The hydraulic cylinder  61  is pivotally secured to the frame  41  of the base  5  and the piston rod  65  is pivotally secured to a plate  47  mounted, such as by welding, to the underside of the beam elements  11 A ( FIG. 3 ). As a result, the support  3 , which is affixed to the platform  43  of the base  5 , can be pivoted with respect to the base by extension or retraction of the piston rod  65  with respect to the housing  63  by operating the telehandler&#39;s hydraulic system. As shown, the support  3  is moveable using the hydraulic cylinder  61  from a generally horizontal position ( FIG. 10 ) to a 45 degree slope ( FIG. 9 ) with respect to the base. The support  3  can be pivoted to substantially any angle within the range. It is contemplated that the range in which the support  3  can be pivoted with respect to the frame  41  of the base  5  can be larger or smaller than the illustrated configuration. Using the controls for the telehandler&#39;s hydraulic system, a telehandler operator can selectively tilt the support  3  about the tilt axis TA to place the roofing panels in a desired slope along their lengths. Thus, roofing panels supported by the support can be positioned and maintained at slope about equal to the pitch of the roof ( FIG. 1 ).  
         [0034]     In operation, the material handler  1  can be used to sheath a pitched roof on a structure using elongate panels of sheet material having a length and a width. The material handler  1  is placed on a smooth, firm surface. Each of the support arms  9  and telescopic beams  7  are adjusted as needed for accommodating the length and width of the selected panel. The support arms  9  are adjusted to accommodate the width of the panels by moving the forward and rearward portions  25 ,  27  of the support arm with respect to the central portion  23 . The length of the panels is accommodated by adjusting the length of the telescopic beams  7 . To change the length of the beam  7 , the pin  15  is removed and the beam elements  11 B- 11 D with smaller cross sections are slid in a longitudinal direction to the desired length. To secure the beam elements  11 B- 11 D at the desired length, the holes  13  of adjacent beam elements are aligned and the pins are inserted therethrough. Using the telehandler T (or other suitable machinery), a plurality of elongate sheet material panels, such as a bundle, are picked up and loaded onto a support. The panels are positioned on the support such that they lie in a stack.  
         [0035]     The forks of the telehandler T are then inserted into two fork tubes  33 ,  35  thereby connecting the material handler  1  to the telehandler T. Pins are inserted into apertures adjacent the distal ends of the forks to secure the handler to the telehandler. Hydraulic hoses from the hydraulic cylinder are connected to the telehandler. After the panels have been positioned on the material handler  1  and the material handler has been securely attached to the telehandler, the telehandler operator uses the controls to actuate the extensible boom of the telehandler to raise the material handler and move it and stack of panels to a desired location. The panels on the support  3  are positioned so that the support is next to the structure and the longitudinal axis LA of the sheet material panels extends transversely to the structure. The operator of the telehandler can use the telescoping boom of the telehandler to raise the material handler  1  to a height corresponding to that of the pitched roof to be sheathed. Next, the operator can tilt the support  3  of the material handler  1  to an angle corresponding to a pitch angle of the pitched roof to be constructed such that the sheet material panels are inclined along their lengths. As a result, the panels can be easily slid lengthwise from the stack on the tilted support onto the structure by roofers on the roof. The roofers can then securing the panels to the structure thereby sheathing the pitched roof.  
         [0036]     When introducing elements of the present invention or the preferred embodiment(s) thereof, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of the elements. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.  
         [0037]     As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

Summary:
A material handler for use by a self-propelled machines to handle elongate panels of sheet material comprises a support adapted to receive and support the elongate panels. A base mounts the support for pivotal movement of the support relative to the base about a tilt axis which is transverse to the length of the elongate panels when held on the support. The base is adapted for connection to the self-propelled machine. A mover drives the pivotal movement of the support relative to the base to selectively tilt the support about the tilt axis so that when the elongate sheets are held by the support the elongate sheets assumes a desired slope along their lengths.