Abstract:
A forward moving powered cart configured to receive a bundle of roof decking sheets, and which cart rides on the each of three spaced adjacent trusses after being crane lifted onto the said roof trusses. The cart has two sets of spaced casters that ride on the 1 st  and 3 rd  truss, while a safety truck on the cart designed to prevent slippage from the two trusses upon which its two sets of casters ride, engages the middle truss of the three. Sheets are removed from the rear for placement and post installation, the cart is moved forwardly an incremental amount.

Description:
FIELD OF INVENTION 
     This invention pertains to a cart for retaining a bundle of metal decking sheets on a rooftop for removal and installation by a work crew. 
     BACKGROUND OF THE INVENTION 
     When tilt up concrete wall buildings and other large commercial structures are built with flat roofs, the roof trusses are spaced from 8 TO 10 feet apart. The roof type often used for placement on the trusses of these buildings are large sheets of steel, 3 feet wide×32-40 feet long. 
     Bundles of 12 or more of these sheets banded together, are hoisted by a crane and placed across a multitude of spaced trusses. Then, according to the conventional technique, each sheet, subsequent to unbundling is moved by a plurality of workers from the pile to the first and subsequent locations adjacent to and in line with the bottom decking member to the particular set of trusses, upon which the pile rests. Then installation transpires as the bundle remains in a static location. 
     On a major building of 100,000 sq foot roof area, thousands of steps are taken by the men and women who lift those 200-300 pound sheets of steel and move each sheet from the pile a distance ranging from three to thirty-six feet from the start point. Such steps amount to huge expenditures just to place the decking members in position for attachment to the trusses. 
     In contrast, workers who utilize the cart of this invention, merely remove a sheet from the rear of the cart install it and move the cart forwardly. There walking pattern is significantly reduced because the cart moves with the bundle from the width of a sheet to the next location another sheet width forward. The invention of this application when used by the workers, will cut the labor cost of laying a steel sheet roof by between 70% and 80%, as contrasted to the hand carry mode used today due to less time spent between sheet installs. 
     SUMMARY OF THE INVENTION 
     A 4 wheeled powered cart configured to receive a bundle of metal decking sheets, and which cart is adapted to ride on the each of three spaced adjacent trusses is lifted by a crane onto three spaced roof trusses. The cart has two sets of spaced casters that ride on the 1 st  and 3 rd  truss, safety means on the cart designed to prevent slippage from the two trusses upon which its two sets of casters ride engages the middle truss of the three. 
     The cart moves forward upon the actuation of the controls of a pneumatic, hydraulic or electric motor. A plurality of sheets of decking, each about the same width as the cart, are stored on an inclined plane, known as the DRS or decking receiving surface, abutting an upstanding rest, for individual removal as needed. A sheet of conventional decking is removed from the pile by the work crew and placed on the trio of trusses between the last most sheet placed on the trusses and the cart. The cart is then moved forward, the equivalent of one width of decking. By such operation the decking layer persons only walk forward. When the cart is empty, the crane on site moves a new pile onto the cart, and after which the deck layer persons commence removing sheets from the new pile of decking sheets until the job is completed. 
     As seen in the figures, the cart has 8 non-pivoting casters in 2 sets of 2 abutting front and 2 abutting rear casters, beneath a super structure having an expanse wider than the caster sets, a control system for forward movement, an inclined decking receiving surface, and safety retention means to keep the cart aligned such that it does not stray from the spaced trusses upon which it has been set by a crane&#39;s boom. 
     The invention accordingly comprises the apparatus which possesses the features, properties, and the selection of components which are amplified in the following detailed disclosure, and the scope of the application of which will be indicated in the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG. 1  is a rear elevational view of this invention. 
         FIG. 2  is aa top plan view thereof. 
         FIG. 3  is a right end sectional view of the apparatus. 
         FIG. 4  is a left end elevational view of the apparatus. 
         FIG. 5  is a center sectional view thereof. 
         FIG. 6  is a rear center perspective view of a portion of this invention. 
         FIG. 7  is a bottom perspective view of a portion of this invention. 
         FIG. 8  is a top rear perspective view of the engine area of this invention. 
         FIG. 9  is a closeup view of the front guide assembly. 
         FIG. 10  is a closeup view of the rear guide roller in the down position. 
         FIG. 11  is a top rear perspective view of the central portion of the inventive apparatus. 
         FIG. 12  is a left closeup view of the guide means and the actuator of the invention. 
         FIG. 13  is a top right perspective view of the center portion of this invention. 
         FIG. 14  is a closeup view of a tilted front truck. 
         FIG. 15  is a closeup view of a rear guide roller &amp; pivot bar partially raised. 
         FIG. 16  is a closeup view of a rear guide roller and pivot bar fully raised. 
         FIG. 17  is a closeup view of a cleat or hitch point for relocation of the apparatus. 
         FIG. 18  is a bottom perspective view of the left wheel assembly of this invention. 
         FIG. 19  is a bottom perspective view of the center portion of this apparatus. 
         FIG. 20  is a view similar to  FIG. 19  but from another vantage point. 
         FIG. 21  is a top left end perspective view of this invention. 
         FIG. 22  is a top right end perspective view of the apparatus. 
         FIG. 23  is a front right perspective view of the apparatus. 
         FIG. 24  is a bottom perspective view showing the transmission connected to the bike chain. 
         FIG. 25  is a diagrammatic view showing how a truck engages a truss to keep the apparatus going straight on its course. 
         FIG. 26  is a perspective view of the emergency stop means if the actuator fails to work. 
         FIG. 27  is a side elevational view of a single roof truss. 
         FIG. 28  is a perspective view of a bundle of sheets of the roof decking referred to in this patent application, but not forming a part of the invention. 
         FIG. 29  shows 2 men removing one sheet from a bundle of such sheets disposed on the cart of this invention. 
         FIG. 30  is a diagrammatic view showing the walk pattern of a worker who installs decking, using the current conventional mode of decking sheet placement. 
         FIG. 31  is a similar diagrammatic view showing the reduced walking pattern of a worker who installs decking removed from the apparatus of this invention. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In  FIG. 1  a rear elevational view of the apparatus is seen. The apparatus  09  has a superstructure  10  which includes an elongated L-beam  11 , designated the rear base spaced from a mirror image front L-beam of similar length as seen in  FIG. 2  and designated  12 , the front base. The base of both beams  11  and  12  face outwardly. These are connected by a cross members  14 A, 14 B, 14 C, 14 D, 14 E and  14 F. Disposed between  14 A and  14   b  and disposed between  14 E AND  14 F are inverted U-channels  24  which as will be discussed carry sets of casters as will be discussed infra. Now turning to  FIG. 3  it is seen that at each end, here the left end, connected to the cross member  14  is an inclined member  17  which is disposed at about a 63 degree angle. This is determined from the fact that inclined member  17  abuts the DRS  15  at a 90 degree angle while the inclination of DRS  15  is set at about 17 degrees. The sum of 17,63 and 90=180, the area of a triangle. At the lower end of each DRS is a stop or foot whose 1.3 elevation is greater than the DRS such as to retain the bundle of sheets of decking. These DRSs are designated  15 A- 15 E. There are 5 of these, but six cross members  14 . See  FIG. 1 , which also includes the control safety assembly  40  which includes the caster wheel  61 , the truck axle  62 , and gear box  63 , as well as the engagement bar  64  discussed infra; and also see  FIG. 2 . The central DRS does not have a cross member  14  there beneath. Rather there are cross members  14  on either side of the central DRS, and the 2 cross members  14  C and D are L beams that face each other and receive an expanded metal surface to serve as a catwalk for maintenance, help in removal of decking sheets and other purposes. As per  FIG. 8  these two cross members  14 C and  14 D extend forwardly beyond the front superstructure member  12 , either as one piece each or as two parts as may be desired for each of the two cross members. A front plate  16  connects the forward ends of  14 C and  14 D. The expanded metal conventional cat walk surface  80  lies between  14 C and  14 D, and L-plates  12  and  11 . While expanded metal  800  is a small square of the same material as  80  between front base  12  and front plate  16  is designated  800 . There is a similar area of expanded metal on the opposite side of the engine  85  not fully visible in  FIG. 8 . Note from  FIG. 8  that the central DRS has no inclined support  17  and no cross member  14 . An upstanding post mounted to an inverted u support  19  disposed at about the middle of the expanded metal. See  FIG. 2 . Engine  85  seen in  FIG. 2  will be discussed infra. 
     Axle assembly  20  seen in  FIG. 1  located between the first 2 and last 2 of the DRSs are seen be an inverted U-channel  24  per  FIG. 7  with depending downward side plates  21  through which pass an axle  22  carrying a pair of tandem casters  23 . 
     Also seen in  FIG. 9  to the rear of the engine  85  is the truss guide assembly  51 , also to be discussed infra. The distance between  15 A and  15 B is about 5 ft. 6 in. This is the distance also between cross bar and  14 C, which serves also as the support for the expanded metal decking. The expanse from the right side  14  F is the same 11 feet to the other decking support  14 D. The distance between each channel  14 C and the center of the inverted U support  19  is about 1 foot 1 inch as is the distance to  14 D also about 1 ft 1 in. Of course spans between members, larger and smaller are contemplated and as such fall within the scope of the invention. The distances recited have been found to give good support to bundles of decking sheets about 32 feet long. While the spacing between the outer casters is about 16 feet, the entire span of the unit is about 22 feet long, but longer units are contemplated for larger decking sheets as the need may arise. See also  FIG. 28  where a typical bundle of decking is seen in perspective. 
     We turn now to  FIG. 3 , which is a sectional view taken at the right end of the apparatus as seen from the rear which is the operational end of the apparatus. The side plates  21  are seen to have the axle aforementioned carrying the tandem casters. A single bolt unnumbered connects the cross member  14  to the inverted U channel there beneath at each end. For ease and convenience of the reader no numbers will be assigned to nuts and bolts used to connect parts together. The expanse of each of the DRSs is about 3 ft 6 inches to accommodate different width decking sheets.  FIG. 4  is a image related to the sectional view of  FIG. 3  but is taken from the left end of the apparatus. One element  13  is seen here, and a specific element  13 , namely  13 B is depicted in  FIG. 1 . A Guide roller assembly  38 , similar to guide roller assembly  59 ,—discussed below—is seen at the opposite end of the apparatus  10 . 
       FIG. 5  is a center sectional view taken from the right side of the apparatus looking to the center. As noted earlier there is no inclined member in the center as DRS  13 C is attached to the upstanding post  80 . See also  FIG. 8 . Whereas in  FIG. 8  the engine  85  is open to the air, in this view the engine is enclosed in a housing,  85 H. The engagement bar  64  of control safety assembly  40 , is used to urge the apparatus forward at its fantastic speed of less that 1 mph is seen in its up or non-actuated position in  FIG. 6 , and down (operative) in  FIG. 5 . More details on this and the other components that are complimentary thereto will be discussed infra. Also seen in this view is connector bar  73  that runs between the face of the rest  13 D opposite from DRS  15 C to a tilted  7  shape bar. This triangle formed of these two elements serves as an extra rest site, so that as sheets of decking are moved off the bundle, they slide down without hitting or damaging the throttle  64 . See  FIGS. 11 &amp; 19 . 
       FIG. 6  is a front center closeup view with the front guides in the up position, and the actuator in up position. 
     In  FIG. 7 , part of the invention  09 &#39;s superstructure  10  is seen, Opposed L-beams  11  and  12  and a cross bar  14  welded or otherwise attached, is seen, in addition to stop  13  which is welded or other wise attached to both the cross bar and the L-beam  11  and to the DRS  15 . One of the two inverted U-channels  24  is seen attached on the underside of the two L-beams, at a right angle to each. Depending down spaced in from the ends of the U-channel  24  are spaced side plates  21  at opposite ends of the U-channel and aligned opposite and spaced from each other at both the front and rear of the apparatus. The location of said plates is slightly inward from the inner edge of the horizontal section of each L-beam. A pin  22  passes through each opposed pair of side plates and is retained therein. Each pin  22  carries a tandem pair of casters, which are preferably about 5 inches in diameter. The caster assembly seen in  FIG. 7  is the left such unit. The right such unit is a duplicate of the unit just described. 
     Seen in  FIG. 9  this view is the front truss guide assembly  51  attached to spaced tubes  50 . By guide plate  52 . Front truss guide assembly is disposed forward of the front L-beam  12 , while the rear truss guide assembly is disposed rearward of the rear L-beam  11 . Since the details of each are the same, only the rear truss guide assembly will be discussed in detail. 
     Turning now to  FIGS. 8 &amp;9 , where the front truss guide  51  is seen. A pair of spaced pipes  50  are retained by pipe clamps  53  to an inverted L-shaped guide plate  52 . A pair of spaced side plates  54  close off the opening beneath the inverted L by depending down from the horizontal portion thereof. A pin  56  extends through a suitable unmarked opening in each of the two spaced side plates  54  and is retained therein. A notched pivot bar  55  having a notch  55 N is attached on each outer extremity of the pin. Attached to the two pivot bars is a rotatable guide roller  59  attached to the pivot bar  55  by a guide mount  60 . If the guide bar is manually pivoted upwardly and outwardly, the roller will move from its vertical orientation to a horizontal position. And can be locked into a fixed position. Note from  FIG. 9  a duplicate of this guide roller arrangement is spaced from the one in view. Though the second one is partially hidden in both  FIGS. 8 &amp; 9 . 
     Disposed between the two vertical plates  54  beneath the horizontal surface of inverted L-plate  52  are a pair of spaced and aligned truck frames  57 . At each end is a truck  58 , which appears similar to the wheels found on railroad car, and which are called trucks. The trucks are each retained in position on a suitably mounted axle  62 . Note that there are not two trucks back to back, at each end of the front truss guide assembly. It is just one truck with two similar faces. See  FIG. 25 . These trucks act as containment wheels. 
     If the front truck hits an impediment it will tilt and ride over the impediment on the groove of the truss while the rear truck of this front guide will stay in the slot of the truss. If the guide bar,  55 , which in it&#39;s normal operating position is downward, hits an impediment such as the framing for a skylight, it will tilt rearwardly, and cause the guide wheel to move upward to a temporary horizontal disposition, until the impediment has been passed by the guide bar  55 . The truck rides within a groove down the middle of the roof truss. See  FIG. 25 . 
     Let us return now to  FIG. 8  and the other aspects of this FIGURE. The expanded metal decking  80  &amp;  800  has already been discussed. The decking serves as a platform for workers to access the engine safely or to access the deadman&#39;s switch  130  to kill the engine, should the engagement bar  64  fail to function. The emergency kill switch is mounted on upstanding post  18  which is supported by undercarriage  88 . More on the undercarriage at the point of discussion of the transmission. Line  131  is the power line from the actuator  64  and serves as a deadman&#39;s line so that there is no power when the actuator is in the off position. 
     Note the large gas tank sitting on top of the engine  85 . While a gas powered engine is seen here, the use of a hydraulic prime mover, a pneumatic prime mover, diesel and electric motors are also contemplated as suitable for this invention. The gasoline engine  85  is a 5.5 horsepower off the shelf Honda 4 cycle engine. 
     Sign  133  may be mounted on the front part of the apparatus  09  in any conventional manner. It can be used for advertising as well as trademark and patent marking. 
     Tucked away near the far front right on beam  12  is one or more standoffs or cable attachment points such as clevis  95 —seen in  FIG. 8 , which can be used by the crane operator to attach his cables when the cart  09  is to be redeployed. See also  FIGS. 21 &amp; 22 . 
     The discussion now moves to the rear of the apparatus.  FIG. 10  illustrates the rear guide from a different perspective. No further discussion is needed as this item has been discussed supra. Now reference is made to  FIGS. 11 and 12 .  FIG. 12  is a closer view of elements of  FIG. 1 , but from a slightly different vantage point. Thus in  FIG. 11 , one sees a portion of the center DSR  15 C, and its rest  13 C, which is attached thereto and to rear beam  11 . A downwardly depending tube  73  connects to an upward facing  7  shaped bar  72  which in turn is secured to an rear inverted L bracket  68 . The purpose of parts  73  and  72  are to protect the throttle (aka the engagement bar)  64  from damage when in the down position. Note the disposition of tube  73  in the middle of the space between the two arms of throttle  64 . The move forward position for the throttle  64  is down while the at rest position for unloading decking sheets is up. The up position is seen in FIGS.  11 , 12 ,&amp;  13 . 
     As seen better in  FIG. 12 , engagement bar  64  is welded or otherwise attached to rotating pin  74  disposed in a pair of spaced plates. At each end of the pin is an angled plate  77  sitting at about a 45 to 60 degree angle upwardly and forwardly. Attached to the top of the angled plate is a bike chain attached to the transmission seen here in part but discussed infra. 
     Bar  64  is seen in its non-operative position. When the engagement bar is pulled down, the plate  77  rotates from it 10 PM facing position, to a 1 or 2 o&#39;clock position. This movement tugs on the bike chain  76  to engage a clutch not seen, that meshes the transmission  93  with the engine  85  to start the engine to create forward movement. As seen in  FIG. 19 , a downwardly and forwardly disposed bar  90  is attached to the undercarriage and has a chain tensioner  91  thereon, which tensioner&#39;s sprockets engages the bike chain to keep it from going slack, which would interfere with the operation of the apparatus. See also  FIGS. 20 and 24 . 
     Returning to  FIG. 12 , the plate  75  is upstanding and is welded or otherwise attached to reverse  7  positioned L-bracket  68 . Bracket  68  has an upstanding bent portion  69  at each end uniformly spaced in from the outside edges. See  FIG. 12 . Disposed on both sides of support  72  are a pair of small vertical plates  78  each with a throughbore  79 . These vertical plates, are best seen in  FIG. 11 . 
     Lock arm  67  is attached to a sleeve  82  which rotates around pin  65  held in position by pin mount  66  attached to the underside of the aforementioned bracket  68 , and by pin plate  83  1:3 attached to the underside of reverse  7  L-bracket  68 . The arm  67  has a notch therein  67 N which can engage the upstanding bent portion a.k.a. stop  69 . Guides  70 , attached by rear guide mounts  71  are normally in a vertical disposition, will move to a horizontal position when lock arm  67  is raised for its notch  67 N to engage stop  69 . 
     A pair of bolts and nuts together designated  92  disposed on the upper surface of rear base  11  connects the undercarriage to the frame which is attached to the underside of base  11 . Reference is also  FIG. 13 , which is a right side view of this same area. Clevis  95  has a lifting cable as from a crane or other carrier attached thereto in this FIGURE. 
     In  FIGS. 8 &amp; 9 , the truss guide assembly is seen in a side view and was discussed in detail. But in  FIG. 14 , one can better see the pivotal mounting of the truck frame  57  since the rear of the two trucks  58  mounted between the 2 truck frames  57  is up while the front unit is down relative to the rear truck. Here one of the two side plates  54  is seen as is the contour of the leading truck, IE., beveled on both sides of the center area, unlike a railroad car truck. 
     In  FIG. 23 , note the direction of MOTION arrow. All elements visible in this view have been discussed elsewhere herein. Twin casters  23  are seen here as well as in other views. 
     In  FIGS. 8 &amp; 9 , the lead guide roller  59  and its pivot bar  55  are seen in the down position which is the normal position when stationary or in motion. But as mentioned earlier when an impediment is encountered by the pivot bar  55  move rearwardly and upwardly. In  FIG. 15 , a view taken at a moment in time when the arm is partially up as is the roller. Contrast this view with  FIG. 16 , where these two elements have rotated a full 90 degrees. 
       FIG. 17  is a closeup view of a hitch point or clevis  95  used by a crane as an attachment point for the relocation of the apparatus either to or from a rooftop. These are conventional off the shelf items available at any hardware store. 
       FIG. 24  is a bottom view showing the transmission,  93 —conventional—and the bike chain connected thereto via a conventional clutch not seen. The chain is connected to the actuator, as discussed infra. 
       FIG. 25  is a front view showing a truck  58  disposed within the slot or groove  98  of a roof truss  97 . Since the truck can not wobble off course as it rides in the groove, it tends to keep the apparatus on a straight course. 
     In  FIG. 26  we see closeup certain elements seen in  FIG. 18 . Mounted on post  18  is the power cable  131 , that goes through the toggle switch  132 . In an emergency an operator can get onto the catwalk, either  80  or  800  and flip the toggle switch  132  to immediately kill the engine  85 , which sits on the engine support  84 , per  FIG. 8  and thus stop forward progress of the apparatus. 
     Now that the apparatus of this invention has been fully discussed, it is important for the reader to put the apparatus into perspective with respect to a large (150,000 sq ft of roofing). Thus in  FIG. 27  a single roof truss  120  is seen. This roof truss forms no part of the 2.3 invention, but is present for explanatory purposes only. Such roof trusses are readily available in the marketplace at varying lengths. 
     In  FIG. 28 , a typical bundle of 12 sheets of decking, designated  121  can be seen. Note the presence of 6 peak flat areas and 5 valley flat areas, in each sheet. 
     In  FIG. 29 , 2 men are seen in the act of unloading one sheet of decking from on top of the bundle of decking. One man is at each end of the street  122 , stopped at a moment in time by the camera shutter. 
       FIGS. 30 &amp; 31  represent a diagrammatic top view of the roof of the same building with a spaced series of trusses, wherein the location of the edge of a placed decking sheet is shown by a dot, such that 6 sheets are placed from front to back along 3 trusses. The top curve in  FIG. 30  which is zig-zagged shows a constant repetition of walking back to the stack of deck sheets, the movement to the second location along the trio of trusses, then to the third location along the trio of trusses, ad infinitum until all 6 sheets have been placed. This is a lot of back and forth walking. In  FIG. 30 , “T” with the down arrow represents the location of one truss of 6 to 10 feet apart. The dots represent the location of a sheet of decking, placed 90 degrees to the length of the truss. 
     But in the other curve which is a stepped curve, and the T arrow and the dot series have the same meaning as in  FIG. 31 . It is readily seen that the worker goes forward, forward in 6 increments and only returns one time, when the trio of trusses has been covered, and the workers must move such that the crane can relocate the cart of this invention to the next trio of trusses. The wavy line is to signify the forward straight ahead path of the movement of the cart. A wavy line was used to avoid confusion with the small arrow associated with the designator lines associated with the T. 
     This is a very significant savings of time and energy for the workers involved. 
     CONCLUSION 
     As can be seen from the comparison of the walk patterns as seen in  FIGS. 30 and 31 , significant steps and time are saved in the placement of a bundle of sheets of steel or other metal roof decking, when the mobile cart of this invention is employed by the workers. This saving of steps and time translates into cost savings on the roof aspect of a large building, especially when the usually 12 sheets are multiplied 200 or 1000 times, for a full building roof. When one does the math and factors in the cost of leasing the machine and adds that to the labor cost of time sent by the workers on the roof, there is a significant cost savings falling to the contractor who uses the cart. It is seen therefore that the invention of this application reduces job labor costs. It is also much safer and reduces the negative physical damage to the workers. 
     Since certain changes may be made in the above described apparatus without departing from the scope of the invention herein involved, it is intended that matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.