초록 ▼

Molds and processes that permit high-speed, mass production of retaining wall blocks having patterned or other processed front faces, as well as retaining wall blocks formed by such processes. The invention permits the front face of the block to be impressed with a pattern or otherwise directly proc

Molds and processes that permit high-speed, mass production of retaining wall blocks having patterned or other processed front faces, as well as retaining wall blocks formed by such processes. The invention permits the front face of the block to be impressed with a pattern or otherwise directly processed, to allow the formation of pre-determined block front faces, while at the same time facilitating high-speed, high-volume production of blocks. Pre-determined front faces can include front faces having pre-determined patterns and textures, front faces having predetermined shapes, front faces made from different material(s) than the remainder of the block, and combinations thereof.

대표청구항 ▼

What is claimed is: 1. A mold assembly for use in forming a pre-cured dry cast concrete block having upper and lower faces, a front face, a rear face, opposed side faces, and an integral flange extending below the lower face of the block, the mold assembly comprising: a plurality of side walls defi

What is claimed is: 1. A mold assembly for use in forming a pre-cured dry cast concrete block having upper and lower faces, a front face, a rear face, opposed side faces, and an integral flange extending below the lower face of the block, the mold assembly comprising: a plurality of side walls defining a mold cavity having an open mold top and an open mold bottom, a first of said side walls including an undercut adjacent the open mold bottom; a pallet having a flat surface that temporarily closes the entire open bottom of the mold cavity, and the undercut and a portion of the flat surface of the pallet define a flange-forming subcavity configured to form the flange of the block; and wherein a second side wall of the mold cavity, which is generally perpendicular to said first side wall, includes a first converging side wall portion that is moveably mounted so that it is movable between a first position at an angle with respect to vertical so that the mold cavity is wider at its top than it is at its bottom when dry cast concrete is introduced into the mold cavity, and a second position in which the bottom of the mold cavity is at least as wide as the top of the mold cavity to allow the pre-cured concrete block to be discharged through the bottom of the mold cavity, wherein the first converging side wall portion extends across the entire distance of the mold cavity between two opposed side walls that are adjacent the second side wall. 2. The mold assembly of claim 1 including a stripper shoe having a face that comprises a three-dimensional pattern for introduction into the mold cavity through the open top of the mold cavity to press the patterned face of the stripper shoe on dry cast concrete contained in the mold cavity, to impart a pattern to the front face of a pre-cured concrete block. 3. The mold assembly of claim 2 wherein the pattern of the face of the stripper shoe simulates natural stone. 4. The mold assembly of claim 3, wherein said stripper shoe includes a flange surrounding the perimeter of the patterned face and said flange is arcuate so as to produce rounded edges on the front face of the concrete block. 5. The mold assembly of claim 1, wherein the remainder of said side wall with said undercut is substantially planar and extends substantially vertically. 6. The mold assembly of claim 1 wherein the side wall of the mold cavity opposite said second side wall includes a second converging side wall portion which is opposite the first converging side wall portion and extends the entire distance across the mold cavity between the two opposed side walls that are adjacent the second side wall, and wherein the second converging side wall portion is moveably mounted so that it is movable between a first position at an angle with respect to vertical so that the mold cavity is wider at its top than it is at its bottom when dry cast concrete is introduced into the mold cavity, and a second position in which the bottom of the mold cavity is at least as wide as the top of the mold cavity to allow the pre-cured concrete block to be discharged through the bottom of the mold cavity. 7. The mold assembly of claim 6, wherein said converging side wall portions are pivoted near ends thereof adjacent the open mold top. 8. The mold assembly of claim 6, further including a mechanism for biasing each of said converging side wall portions to the first position. 9. The mold assembly of claim 8, wherein the mechanism for biasing each of said converging side wall portions comprises an air bag connected to each converging side wall portion. 10. The mold assembly of claim 6, wherein each of said converging side wall portions includes a substantially planar surface facing the mold cavity. 11. The mold assembly of claim 1 comprising a plurality of said mold cavities which operate with a single pallet to mold a plurality of blocks at the same time. 12. A mold assembly according to claim 2, wherein said stripper shoe includes a flange surrounding the perimeter of the patterned face. 13. A mold assembly according to claim 12, wherein said stripper shoe flange is arcuate so as to produce rounded edges on the front face of the concrete block. 14. A mold assembly according to claim 12, wherein: a second side wall of the mold cavity is generally perpendicular to the first side wall of the mold cavity and includes a first converging side wall portion movably mounted between a first position and a second position; the first position of the first converging side wall portion being at an angle with respect to vertical to provide that the mold cavity is wider at the cavity top than at the cavity bottom when dry cast concrete is introduced into the mold cavity; the second position of the first converging side wall portion providing that the bottom of the mold cavity is at least as wide as the top of the mold cavity to allow the pre-cured concrete block to be discharged through the bottom of the mold cavity; and the first converging side wall portion extends across an entire distance of the mold cavity between the opposed side walls adjacent to the second side wall. 15. A mold assembly for use in forming a pre-cured dry cast concrete block having an upper and lower face, a rear face, opposed side faces, and an integral flange extending below the lower face of the block, the mold assembly comprising: a plurality of side walls defining a mold cavity having an open mold top and an open mold bottom, a first of said side walls including an undercut adjacent the open mold bottom; a pallet having a flat surface that temporarily closes the entire open bottom of the mold cavity, and the undercut and a portion of the flat surface of the pallet define a flange-forming subcavity configured to form the flange of the block; a stripper shoe having a face that comprises a three-dimensional pattern for introduction into the mold cavity through the open top of the mold cavity to press the patterned face of the stripper shoe on dry cast concrete contained in the mold cavity, to impart a pattern to the front face of a pre-cured concrete block; wherein a second side wall of the mold cavity, which is generally perpendicular to said first side wall, includes a first converging side wall portion that is moveably mounted so that it is movable between a first position at an angle with respect to vertical so that the mold cavity is wider at its top that it is at its bottom when dry cast concrete is introduced into the mold cavity, and a second position in which the bottom of the mold cavity is at least as wide as the top of the mold cavity to allow the pre-cured concrete block to be discharged through the bottom of the mold cavity, wherein the first converging side wall portion extends across the entire distance of the mold cavity between two opposed side walls that are adjacent the second side wall; and wherein the side wall of the mold cavity opposite said second side wall includes a second converging side wall portion which is opposite the first converging side wall portion and extends the entire distance across the mold cavity between the two opposed side walls that are adjacent the second side wall, and wherein the second converging side wall portion is moveably mounted so that it is movable between a fist position at an angle with respect to vertical so that the mold cavity is wider at its top that it is at its bottom when dry cast concrete is introduced into the mold cavity, and a second position in which the bottom of the mold cavity is at least as wide as the top of the mold cavity to allow the pre-cured concrete block to be discharged through the bottom of the mold cavity. 16. The mold assembly of claim 15, wherein the pattern of the face of the stripper shoe stimulates natural stone. 17. A mold assembly according to claim 15, wherein the stripper shoe includes a flange surrounding the perimeter of the patterned face. 18. The mold assembly of claim 17, wherein the stripper shoe flange is arcuate so as to produce rounded edges on the front face of the concrete block. 19. The mold assembly of claim 15, wherein the remainder of said side wall with said undercut is substantially planar and extends substantially vertically. 20. The mold assembly of claim 15, wherein said converging side wall portions are pivoted near ends thereof adjacent the open mold top. 21. The mold assembly of claim 15, further including a mechanism for biasing each of said converging side wall portions to the first position. 22. The mold assembly of claim 15, wherein the mechanism for biasing each of said converging side wall portions comprises an air bag connected to each converging side wall portion. 23. The mold assembly of claim 15, wherein each of said converging side wall portions includes a substantially planar surface facing the mold cavity. 24. The mold assembly of claim 15 comprising a plurality of said mold cavities which operate with a single pallet to mold a plurality of blocks at the same time.