FIELD OF THE INVENTION
This invention relates to apparatus and methods for forming concrete walls and particularly for efficiently manufacturing a plurality of long concrete wall panels.
SUMMARY OF THE INVENTION
In one embodiment, a plurality of concrete wall panels are manufactured in a panel forming apparatus providing a series of parallel hollow molding compartments. These compartments may be of varying length and width. Steel cables under tension maintain the integrity of the shape of each compartment when subjected to the extreme pressure applied against the walls of the compartment by the liquid concrete.
Steel rebar and mesh kits are supported within the compartments and concrete is then poured into each compartment. The poured concrete is vibrated by a ganged series of electrical vibrators to remove trapped air bubbles which would otherwise mar the attractive appearance of the finished wall panel.
After the poured concrete has set, the parallel compartments are opened and the concrete wall panels typically lifted from the panel forming apparatus by a crane.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the concrete panel forming apparatus and one embodiment of the tension cable system.
FIG. 2 is another view of a longitudinal side of the panel forming apparatus and tension cable system.
FIG. 3 is a side perspective view of the panel forming apparatus showing the series of movable wall forming members supported by steel V-groove wheels riding on a top rail of the apparatus.
FIG. 4 illustrates another longitudinal side of the panel forming system and its tension cable system.
FIG. 5 illustrates the manner in which the movable panels travel on the overhead track to form the plurality of molding compartments used to mold poured concrete into a plurality of concrete panels.
FIG. 6 is a top perspective view showing the steel rebar/mesh kits hanging in respective molding compartments formed by the movable panels and by spaces.
FIG. 7A is a side elevational view showing the placement of spacers to form the width of molded panels.
FIG. 7B is a perspective view of individual spacer members.
FIG. 8A is a perspective view illustrating short panel blanks.
FIG. 8B is a perspective view illustrating the manufacture of shorter panels using short panel blanks.
FIG. 9 illustrates preparation of the rebar/mesh kit.
FIG. 10 illustrates the steel cap covering the top of a movable panel.
FIG. 11 illustrates spraying of release agent onto the texture molding liner of a movable panel.
FIG. 12 illustrates pouring concrete into each of the molding compartments.
FIG. 13 illustrates the gauged vibrators used to fill in gaps and remove air bubbles.
FIG. 14 illustrates removing a molded concrete panel from the panel forming apparatus.
FIG. 15 is another view showing removal of a concrete panel.
FIG. 16 is a top elevational view of a mobile panel forming apparatus.
FIG. 17 is a side elevational view of a mobile panel forming apparatus.
DETAILED DESCRIPTION
Superstructure
The panel forming apparatus can include, as shown in the embodiment illustrated in FIGS. 1-5, a four-sided steel superstructure 100 having a first longitudinal side 105, a second longitudinal side 110, and two end sides 115 and 120. This steel superstructure is designed to contain the very high pressures exerted by the poured liquid concrete used to form the concrete panels. In the embodiment shown, the four sides 105, 110, 115, 120 are each four sided steel frames reinforced by a plurality of welded sections of vertical and horizontal steel bars in the longitudinal panels 105, 110 and welded sections of vertical steel bars in the ends 115 and 120. The floor 121 is a steel plate. The superstructure 100 may be typically supported on, for example, hard ground, a concrete pad, or on a steel or wood joists or as described below on a mobile chassis.
The size of the superstructure will typically be determined by the length of the concrete panels to be molded and allow sufficient room so that workers can have ready access between any two of the movable wall forming panels 125 described below.
Movable Wall Forming Panels
A plurality of movable wall forming panels 125 are movably supported inside the superstructure 100. In the embodiment shown in FIGS. 1-5, twelve such panels are utilized. The face of each panel can be formed from sheets of steel ⅛ inches thick which are welded on opposite sides of a reinforcing supporting steel rib structure. As shown in FIGS. 3 and 5, each panel can be supported by an attached overhead steel beam 130. Beams 130 are movably supported by steel V-groove wheels 140, 141. The V-groove wheels 140, 141 respectively ride on tracks 135, 136 welded to respective top beams 137, 138 of end frames 115, 120. The V-grooved wheels 140, 141 rotate on respective axles 145 attached to vertical end members 150. The members 150 are respectively welded to the opposite ends of beam 130. In the embodiment shown, the first movable panel 125A is extra thick and heavy and is therefore supported by two sets of the V-groove wheels.
As shown in FIG. 5, the plurality of movable panels 125 and 126 are moved along the tracks 135, 136 until reaching spacers 165 placed at opposite ends of the movable panels, as shown in FIGS. 1 and 6, and forming a plurality of parallel wall molding compartments or cavities 160 (FIGS. 3 and 6) into which the liquid concrete is poured to form the sections of concrete fence. In the embodiment shown, twelve such compartments 160 are formed. Eleven compartments 160 are formed between respective movable panels and the twelfth formed between the last movable compartment 125L and a steel plate 126 welded to the fixed superstructure wall 105.
The top of each movable panel 125 and fixed wall 105 can be covered as shown in FIG. 10 by a steel cap 127 welded at the top of the panel to cover the steel sheets on opposite sides each panel and the texture/pattern liners described below so as to prevent concrete from leaking between the steel panel and texture/pattern liners.
Spacers and Short Panels
The maximum length of each concrete section is determined by the length of the panel 125. The width (thickness) of each molded concrete panel is determined by the width of the spacer 165 placed between each of the panels 125 as shown in FIGS. 6 and 7A. Individual spacer members 165 of different width are shown in FIG. 7B.
The length of the cavity can also be varied to mold shorter panels by using panel blanks 167, 167′ of predetermined width as shown in FIG. 8A. Each block has the height of the molding compartment 160. The panel blocks 167 are formed with predetermined widths and thickness. In use, a panel blank is located in a selected cavity 160. After the blanks 167 are inserted in selected mold cavities, as shown in FIG. 8B, liquid concrete is poured into the molding compartment to manufacture a panel of selected lengths that is less than the maximum provided by the length of movable panel 125, 126. Panel blanks 167, 167′ can be formed using a number of different materials. By way of example, suitable blanks can be formed through the use of foam encased in Polyurea. By way of specific example, suitable blocks have been formed using 3LB density foam encased in a ¼″ thick layer of Polyurea.
FIG. 8B illustrates vertically stacking plural blanks 167′ to achieve a cement panel of predetermined length. Plural blanks can also be horizontally stacked within a molding compartment to achieve the desired panel length.
Accordingly, an aspect of the embodiment shown is that both the length and width of the manufactured concrete wall panels can be varied by use of spacers 165 (FIG. 7) and short panel blanks 167 of selected width. Thus, as a result, the embodiments described can be used to both manufacture twelve very long fence panels 17.5 feet long, 8 feet high and 5 inches thick, but also can be used to manufacture shorter panels and thicker or thinner panels.
Tension Systems
The weight of the liquid concrete subjects the movable panels 125 to extreme pressure at their mid-length. Any structural deformation of a panel 125 will result in a defective molded concrete wall. Such forces have heretofore made it impractical to vertically mold very long panels of 14 feet or more from poured concrete.
In the embodiment shown, however, the tension system 175 maintains the integrity of the superstructure walls 105, 110 against bowing or distorting to thereby successfully oppose the very high pressures exerted upon the movable panel wall forms 125 when the cavities 160 are filled with wet concrete.
Tension system 175 can include, as shown in FIGS. 1-3, a tension cabling system having adjustable struts 180 held perpendicular to the longitudinal sides 105 and 110 of super structure 100. The proximal end 185 of each strut is engaged in a receiver 186 welded to the longitudinal wall 105 or 110. The distal end 187 of the strut 180 includes a slotted receptacle 188 for receiving a tension wire cable 190. Opposite ends of cable 190 are attached to respective opposite end beams of the frame forming longitudinal side 105.
In the embodiment shown, the tension supplied by cable 190 is adjusted by a turn screw apparatus on each strut 180. As shown in FIGS. 1-3, each strut 180 includes juxtaposed end members 185, 187, a threaded rod 200, and mating threaded handle 205. One end of rod 200 is fixedly attached to end member 185 and the opposite end of the rod 200 is longitudinally supported for sliding movement with member 187. Accordingly, rotation of handle 205 in the appropriate direction will result in engagement of handle 205 against member 187. Continued rotation of handle will force members 187 and member 185 to move further apart thereby lengthening strut 180 and increasing the tension on cable 190. Rotation of the handle 205 in the opposite direction will reduce the distance between members 185 and 187 and thus decrease the tension on cable 190.
Further, as shown in FIG. 2, the adjustable struts 180 are maintained in a stable horizontal orientation orthogonal to the longitudinal walls 105, 110 by attaching a cable 210, between struts 180. Respective cables 215 and 220 are attached to respective distal ends of struts 180 and respectively to the upper and lower hooks attached to the longitudinal wall 105.
The tension system 175 thus maintains a constant tension force on the midsection of walls 105, 110. These tension forces are transferred to the movable panels 125 after the panels 125 have been moved along tracks 135, 136 to set-up a plurality of molding compartment panels.
Texture or Pattern
The concrete wall panels can be manufactured with a variety of textures or patterns by securing a liner to the face of the movable wall forming panel 125 and wall 126. This liner is typically a thin sheet of rubber or plastic the same size as the panel 125 and wall 126 having a pattern formed on its outer face which is the reverse image of the desired pattern on the concrete wall. In one embodiment, the rubber or plastic liner is attached to the supporting steel plate with a combination of screws and liquid nails placed primarily near the horizontal ends of the panel 125 so that any imprint of the screw on the molded concrete wall will be hidden inside a column erected when the fence is installed.
Safety Platforms
During molding of concrete fence panels, the workers on top of the superstructure 100 are 6 or more feet above ground. A safety device for these workers is provided by safety platform 250 having side rails 255 and attached, as shown in FIG. 3, along both ends of the superstructure 100.
Rebar/Mesh Kit
Steel mesh and rebar is tied together to provide a rebar/mesh kit 260. Kit 260 is supported within each molding compartment 160 before concrete is poured. As shown in FIGS. 6 and 9, the kit 260 is advantageously the length of the concrete wall panel to be formed. The mesh can be typically constructed from 8 gauge wire to form a mesh with 6-inch squares. A length of rebar 270 is threaded throughout loops 275 of the mesh.
The rebar/wire mesh kits 260 are respectively hung in approximately the center of each cavity 160. As shown in FIG. 6, the rebar 270 of each kit is hung from a cross support member 280. Typically, the rebar/wire mesh kit 260 touches the bottom of the compartments and extends to within an inch of the tops and sides of each movable wall forming panel 125. Thus, the kits 260 typically extend substantially the length and height of each compartment 160.
Manufacturing the Concrete Wall Panels
The manufacture of concrete wall panels begins with moving panels 125 to open space for a worker between wall 126 and panel 125L. As shown in FIGS. 3 and 11, the superstructure 100 and tracks 135, 136 provide ample room for accommodating workers during set-up.
Starting with the wall 126 on the inside of end 105 of superstructure 100, a textured or patterned liner may be attached (or a different one substituted for one already attached) to wall 126 and the facing wall of panel 125L. A release agent is then applied to all textured surfaces of wall 126 and the facing wall of panel 125L to prevent sticking of the concrete during extraction of a finished concrete wall panel. FIG. 11 illustrates at 350 spraying of the release agent.
A completed steel rebar/mesh kit 260, spacer 165 (and short panel blank 167 if used) are then located against wall 125. The rebar/mesh kit 260 is positioned to reach to or close to the floor 121.
A rubber sealing mat is laid at the bottom of each molding compartment 160 on floor 121 so that when the wall panels 125 are pushed together, the bottom of each wall 125 is sealed to prevent concrete from leaking out between the bottom of each panel 125 and floor plate 121.
The foregoing steps are repeated until all of the twelve compartments have been prepped. Once all of wall forming panels 125 have been pushed together to form the molding compartments 160, the first movable wall panel 125A is placed under stress by a series of horizontal anchor struts 295 shown in FIG. 4. These anchor struts 295 are held in receptacles 300 welded to this open end 110 of superstructure 100 and receptacles 305 in the movable wall panel 125A.
In the embodiment shown, the anchor struts 295 each include turn screws so as to be adjustable in length and may, for example, be similar in function to the struts 180 described above. Thus, as a threaded lever 310 is turned to lengthen a strut 295, force is applied between the superstructure wall 110 and movable wall forming panel 125A. This force is resisted by tension system 175. As a result, the forces produced when liquid concrete is poured into the compartments 160 will be countered by the tension system 175.
On top of the superstructure 100, lifting lugs or hooks 380 are attached to a steel holding plate of 4 inch wide by 10 feet long and ⅛ inch thick. The holding plate has ¾ inch holes through which the threaded lifting lug bolt is inserted and threaded into the lifting lug component that will be encased in concrete.
Concrete is then pumped in the normal manner from a concrete truck and concrete pump through pipes or tubes to a trough 350 shown in FIG. 12. Concrete is poured into each of the molding compartments 125 and evenly distributed through all compartments during the fill so as to prevent excessive pressure from building up in individual compartments. A gang of six vibrators 360 having depending wands 365 shown in FIG. 13 are lowered in compartments 160 into the liquid poured concrete to fill in any gaps and remove air bubbles. By way of specific example, suitable vibrators are sold by Northrock Industries, Inc., Medford, N.Y. The six vibrators 360 vibrate one half of a single compartment 160 and are then moved to vibrate the other half of a compartment 160. They are typically used both while concrete is being poured and after all of the compartments 160 are filled with concrete. The vibrators are lowered quickly all the way to the bottom of a compartment until they hit the rubber seal mat on the floor of the superstructure 100. The vibrators are then lifted slowly through the poured concrete by the crane 370, and then quickly lowered into an adjacent compartment, then raised slowly again.
After vibration of the poured concrete has been completed, the entire top of each compartment 160 is scraped smooth so that the top of the concrete wall panels will be smooth.
After the concrete has set, the finished panels are extracted from the molding compartments 160. The anchor struts 295 (FIG. 4) are removed and the first movable wall forming panel 125A is pushed away along tracks 135, 136 to expose the finished concrete wall panel. The spacers 165 used to form the first concrete panel are then removed and a crane 365 with a spreader bar 375 is attached to the hooks 380 to lift the formed concrete panel from the superstructure 100 as shown in FIGS. 14 and 15. Successive concrete panels are exposed and removed in the same manner.
Mobile Panel Forming Apparatus
A mobile panel forming apparatus 400 is shown in FIGS. 16 and 17. The superstructure 405 can be constructed in the same manner as the stationary superstructure 100 described above, but mounted, in the embodiment shown, to an industrial flat bed trailer.
The trailer mounted unit shown is designed to have a width no greater than 104″ so as to not require oversize road permits. In order to accommodate this width restriction, the unit 400 includes ten movable wall mounting panels 425.
After the mobile apparatus 400 is moved to an on-site location, stabilizers 430 are lowered to the ground and used to lift the trailer 410 and its tires 435 off the ground. As a result, the substantial weight of the concrete when poured into the wall panel molding compartments does not need to be supported by the tires 435.
Although the foregoing apparatus and methods have been described in terms of certain preferred embodiments, other embodiments will be apparent to those of ordinary skill in the art from the disclosure herein. Additionally, other combinations, omissions, substitutions and modifications will be apparent to the skilled artisan in view of the disclosure herein. While certain embodiments of the inventions have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel methods and systems described herein may be embodied in a variety of other forms without departing from the spirit thereof. Accordingly, other combinations, omissions, substitutions and modifications will be apparent to the skilled artisan in view of the disclosure herein.
Patent Application
20090000242
