Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B28—WORKING CEMENT, CLAY, OR STONE
  • B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
  • B28B7/00—Moulds; Cores; Mandrels
  • B28B7/0029—Moulds or moulding surfaces not covered by B28B7/0058 - B28B7/36 and B28B7/40 - B28B7/465, e.g. moulds assembled from several parts
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B28—WORKING CEMENT, CLAY, OR STONE
  • B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
  • B28B7/00—Moulds; Cores; Mandrels
  • B28B7/24—Unitary mould structures with a plurality of moulding spaces, e.g. moulds divided into multiple moulding spaces by integratable partitions, mould part structures providing a number of moulding spaces in mutual co-operation

Definitions

• the present invention relates to a mold for forming molded concrete products, and, more particularly, to a unitary mold for forming molded concrete products.
• That invention increased vibration control in a concrete product forming machine, reduced the amount of time required to mold concrete products, increased the homogeneous consistency of concrete products, and reduced the amount of time required to exchange and align molds in a concrete product forming machine.
• a novel self-aligning mold box assembly for use in a machine for forming concrete products such as the machine disclosed in U.S. Patent No. 5,395,228 to Aeseth et al., is disclosed in my U.S. Patent Application Serial No. 08/361,790, filed in the U.S. Patent and Trademark Office on December 21, 1994, and which is directed to the mold box depicted in FIG. 1.
• Fig. 1 A included therein is an exploded view of a prior art paver grid assembly 100, which includes a paver grid 110 and a paver grid frame 112. In operative condition, paver grid 100 is secured to and contained within frame 112. The upper surfaces of the paver grid and frame are substantially coplanar when the grid and frame are in operative condition.
• Paver grid frame 112 includes a pair of opposed mounting brackets 114,
• Each of the mounting brackets has a pair of upwardly directed mounting surfaces, like surfaces 118, 120 on bracket 114.
• Each mounting surface 118, 120 includes a pair of bolt holes therethrough.
• Mounting bracket 116 includes mounting surfaces and bolt holes that are substantially symmetrical with mounting surfaces 118, 120 and the bolt holes therein.
• a head assembly 122 is, in operative condition, mounted on a machine for making concrete products like that shown in Fig. IB.
• the head assembly includes plurality of compression shoes, like shoe 124, which are aligned with corresponding cavities in paver grid 110, also mounted on the machine.
• wet concrete product is poured into the cavities in paver grid 110.
• the machine moves head assembly downwardly and the shoes, like shoes 124, compress the product into the paver grid cavities.
• a pallet 126 lowers concurrently with head assembly 122 thus stripping the molded pavers from the grid and leaving them arranged on the pallet as shown in Fig. 1 A.
• Fig. IB indicated generally at 128 is a machine for molding concrete blocks and pavers. Included therein are four blocks, like block 130, arranged on pallet 126.
• the mold that formed blocks 130 has been removed from the machine.
• the visible portion of the mounting structure comprises a die support 130.
• a pair of bolt heads can be seen extending downwardly from die support 130.
• mounting surface 120 is urged against the lower surface of die support 130.
• Each of the other mounting surfaces on paver grid assembly 100 are urged against corresponding die supports (not visible).
• the bolts visible in Fig. IB are thereafter used to bolt each of the mounting surfaces firmly against the underside of the die support thereby securing paver grid assembly on machine 130.
• the mold box is vibrated by a pair of opposed vertical vibrating rods 132,
• FIG. 1A Another die support (not visible) is located adjacent rod 133.
• a semicircular notch between mounting surfaces 118, 120 is formed to accommodate vibrating rod 132.
• Vibrating rod 133 is similarly accommodated by corresponding structure (not visible) on mounting bracket 116.
• the vibrating rods like rod 132, vibrate the mold while the shoes, like shoe 124, compact wet concrete product into the cavities. The vibration during compaction increases density, and therefore strength, of the molded concrete product.
• the unitary mold of the present invention includes upper and lower surfaces, opposed side and end portions, and internal surfaces which define a plurality of concrete-receiving voids.
• mounting spacers are mounted on the lower surface of the unitary mold adjacent each end.
• the mounting spacers include precisely positioned holes for receiving locating pins to precisely locate the unitary mold on a support surface.
• Also mounted on the bottom surface adjacent each side are mounted longitudinal support rails.
• Fig. 1 is an exploded perspective view of a prior art mold box assembly.
• Fig. 1 A is an exploded perspective view of a prior art head assembly, paver grid assembly, and pallet.
• Fig. IB is a perspective view of a prior art machine that can incorporate the structure depicted in Fig. 1 A to make pavers.
• Fig. 2 is a top plan view of the unitary mold according to the present invention.
• Fig. 2 A is an end view of the unitary mold shown in FIG. 2.
• Fig. 3 is a side view of the unitary mold shown in FIG. 2.
• Fig. 3A is a bottom plan view of the unitary mold shown in FIG. 2.
• Fig. 4 is a top plan view of the central mold grid which is incorporated in the embodiment shown in FIG. 2.
• FIG. 4A is an end view of the central mold grid shown in FIG. 4.
• FIG. 5 is a side view of the central mold grid shown in FIG. 4.
• FIG. 5 A is a bottom plan view of the central mold grid shown in FIG. 4.
• FIG. 6 is a partial enlarged bottom plan view of the central mold grid shown in FIG. 4 showing in greater detail a typical mold opening.
• FIG. 7 is a top plan view of a cover plate used to cover the peripheral voids formed in the central mold grid of FIG. 4.
• FIG. 8 is a side view of the longitudinal support member shown in FIG. 3A.
• FIG. 9 is a top view of the longitudinal support member shown in FIG. 8.
• FIG. 10 is a bottom plan view of a mounting spacer which is mounted on the bottom surface adjacent each end of the unitary mold shown in FIG. 2
• FIG. 11 is a side view of the mounting spacer shown in FIG. 10.
• FIG. 12 is a top plan view of the pan angle that is mounted on the unitary paver mold shown in FIG. 2.
• FIG. 13 is a side view of the pan angle shown in FIG. 12.
• FIG. 14 is a top plan view of the pallet guide that is mounted on the unitary paver mold shown in FIG. 2.
• FIG. 15 is an end view of the pallet guide shown in FIG. 14.
• FIG. 16 is a perspective view of a concrete molding machine of the type on which a unitary mold shown in FIG. 2 is mounted.
• FIG. 17 is a perspective view of the concrete molding machine shown in
• FIG. 16 with the unitary mold of FIG. 2 mounted thereon.
• Fig. 18 is an exploded perspective view of a head assembly, a paver grid (being another embodiment of the present invention), and pallet.
• Figs. 19, 20 and 21 are side, plan and left-end views of another paver grid embodiment of the invention.
• Fig. 22 is a perspective view of the paver grid of Figs. 19-21.
• Fig. 23 is a view similar to Fig. 22 depicting hidden structure and dashed lines.
• Unitary paver mold 10 includes a mold grid member shown generally at 12 which includes a central mold grid 13 disposed within sides 14 and 16, and ends 18 and 20. Mold grid 13 defines multiple openings 21 which are shaped to form concrete to the desired shape, and which are open on the top and bottom (FIG. 6). Openings 15 are formed in mold grid member 12 to equalize the thermal mass distribution across the span of the mold grid member. Equalization of the thermal mass promotes even heating and cooling of the member during heat treating, and results in less distortion of the member during heating and cooling.
• Each opening 15 is covered by a plate 17 as shown in FIG. 7, and which is welded into place on the top surface of the mold grid member 12.
• a plate 17 as shown in FIG. 7, and which is welded into place on the top surface of the mold grid member 12.
• pan angles 19 and 21 Mounted on the upper surface of the mold grid member 12 are pan angles 19 and 21 which serve to contain wet concrete in the mold grid member.
• unitary paver mold 10 includes longitudinal support rails 22 and 24 which are mounted with bolts 26 to the bottom surfaces of sides 14 and 16 respectfully, and which are parallel to and positioned outside of the lateral edges of mold grid 12.
• Support rails 22 and 24 in the preferred embodiment are 5" tall and serve to limit deflection of the mold grid member as described more fully below.
• a mounting spacer 28 is mounted on the lower surface of the mold grid 12, and serves to precisely space the unitary paver grid 10 above a supporting platen 30 in the molding machine 32 as shown in FIGS. 16 and 17.
• a unitary paver mold according to the present invention is filled with wet concrete, the wet concrete is compacted by a pneumatically activated press 34 as shown in FIG. 14.
• the filled mold assembly is vibrated at a relatively high frequency, e.g. 50 hz., and a displacement of from 0.050 to 0.100". Doing so naturally exerts high bending moments in the mold.
• Applicant's invention provides, for the first time, a unitary mold which has a capacity of greater than the equivalent of 3 - 8"x8"xl6" blocks, which exhibits acceptably low bending displacement during vibratory compaction of the wet concrete, and which is readily easily used with existing molding machine designs.
• a paver mold as shown in FIGS. 2 - 3 A, when vibrated at 50 hz. and a displacement of 0.090" exhibited vertical bending at its longitudinal midpoint of approximately 0.0085", which is well within the acceptable maximum of 0.010".
• head assembly 122 and pallet 126 are substantially identical to those described in Fig. 1 A and retain corresponding identifying numerals in Fig. 18.
• Paver grid 134 is constructed in accordance with the present invention and includes a substantially planar grid plate 136 in which a plurality of cavities are formed for molding concrete pavers, like those shown on pallet 126.
• a pair of stiffener rails 138, 140 are bolted to the underside of grid plate 136 as shown.
• Each end of grid plate 136 includes a mounting plate, like mounting plate 142, bolted thereto via bolts (not shown) received in four bores, like bore 144, in grid plate 136.
• FIGs. 19-23 another embodiment of the paver grid depicted in Fig. 18 is shown. As can be seen, it includes larger cavities, and therefore a fewer number of cavities, for molding larger concrete products than the paver grid in Fig. 18. Numerals corresponding to those used in Fig. 18, however, are used in Figs. 19-23 to identify similar structure.
• Each mounting plate includes a pair of upwardly directed mounting surfaces, like surfaces 146, 148 on mounting plate 142.
• Mounting plate 142 is received in a recess 150 formed on the underside of grid plate 136, as best view in Fig. 21.
• Plate 142 is secured to grid assembly 136 via four bolts (not shown) received through countersunk bores, like bore 144, in grid plate 136, and coaxial bores (visible in dashed lines in Fig. 23) in the mounting plate.
• Rails 138, 140 are likewise bolted to the underside of grid plate 136.
• mounting surfaces 146, 148 are urged against the underside of the die supports, like die support 130, on machine 130 and are thereafter bolted in the same fashion as the prior art paver grid assembly of Fig. 1 A. Molding a product thereafter proceeds as previously described, and as is well known in the art. Stiffener rails 138, 140 prevent excessive flexing of paver grid 136 during the manufacturing process. Paver grid assembly 134 is cheaper to make than the prior art paver grid of Fig. 1 A because it has fewer parts. In addition, the sides of the grid need not be machined to fit in a frame as in the prior art. Only the undersurfaces to which the rails and mounting plates are bolted need be machined to permit securing parts together.

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• Engineering & Computer Science (AREA)
• Manufacturing & Machinery (AREA)
• Chemical & Material Sciences (AREA)
• Ceramic Engineering (AREA)
• Mechanical Engineering (AREA)
• Moulds, Cores, Or Mandrels (AREA)
• Press-Shaping Or Shaping Using Conveyers (AREA)
• Road Paving Structures (AREA)

Applications Claiming Priority (5)

Publications (3)

Family

ID=26677139

Family Applications (1)

Country Status (5)

Families Citing this family (1)

Citations (3)

Family Cites Families (3)

• 1998
  • 1998-09-03 ES ES98946851T patent/ES2215322T3/es not_active Expired - Lifetime
  • 1998-09-03 DE DE69821375T patent/DE69821375T2/de not_active Expired - Lifetime
  • 1998-09-03 AU AU93779/98A patent/AU9377998A/en not_active Abandoned
  • 1998-09-03 EP EP98946851A patent/EP1019226B1/de not_active Expired - Lifetime
  • 1998-09-03 WO PCT/US1998/018461 patent/WO1999011443A1/en active IP Right Grant

Patent Citations (3)

Non-Patent Citations (1)

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