# US 4,395,220 A · Apparatus for forming construction blocks > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 4,395,220 A - Document ID: US4395220A - Status: Granted - Kind: A - Application number: 06/271,599 - Filed: 1981-06-08 - Granted: 1983-07-26 - Earliest claimed: 1981-06-08 - Inventors: Warren L. Harter - Web page: https://patentgrep.com/patent/US4395220A ## CPC - B28B 1/44: by forcing cores into filled moulds for forming hollow articles - B28B: SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER (foundry moulding B22C; working stone or stone-like material B28D; shaping of substances in a plastic state, in general B29C; making layered products not composed wholly of these substances B32B) ## Abstract This invention relates to an apparatus and a process for forming building blocks by consolidating a mixture of cement and fibrous material. The process involves placing a charge of the mixture into a mold, compressing the mixture within the mold, inserting rotors into the mixture within the mold to consolidate and displace the mixture while forming hollow cores through the formed block, and removing the rotors from the formed block and the block from the mold. The apparatus includes a mold, a mold cover, means that apply pressure to the mold cover to compress the material placed within the mold rotors, means for spinning the rotors as they are lowered into and raised from the mixture by raising and lowering means. The block is formed on a removable pallet resting on lips within the mold. The pallet defines apertures substantially aligned with the rotors; the apertures allow for release of pressure when the rotors are withdrawn from the formed block. The rotors are uniquely configured to properly compact and displace the mixture and to form smooth hollow cores through the block. ## Claims ### Claim 1 A rotor for displacing and compacting materials smoothly and evenly while producing a cylindrical hollow core through a formed block, comprising: a continuous smooth cylindrical outer surface formed about a center axis; a curved vane projecting axially outward from one end of the cylindrical surface to an outer edge lying within a plane perpendicular to the axis of the smooth cylindrical surface; said curve vane having a radial edge that intersects said outer edge and is an extension of said cylindrical surface; the vane presenting a transversely curved convex face in the intended direction of rotation of the rotor; the face of the vane having a radial orientation at the center axis of the cylindrical surface and constantly receding from the direction of rotation spirally to a tangential orientation at the cylindrical surface. ### Claim 2 (depends on 1) A rotor as defined in claim 1 including a plurality of curved vanes. ### Claim 3 (depends on 2) A rotor as defined in claim 2, wherein the vanes are configured to present an S-shaped outer edge. ### Claim 4 (depends on 3) A rotor as defined in claim 3, wherein: the smooth surface includes a cone-shaped projection having a base centered about the center axis of the cylindrical surface; the base of the cone being congruent with the circumference of the cylindrical surface; the cone having an outside surface projecting outward from the end of the cylindrical surface to an apex intersecting the plane perpendicular to the axis of the cylindrical surface. ### Claim 5 An apparatus for forming construction blocks from a mixture of cement and fibrous materials, comprising: a confining mold having an interior for receiving and shaping a controlled charge of the mixture; a mold cover having a circular aperture formed through it; means for applying pressure to the mold cover in a first direction for pressing the mixture into the confining mold; a rotor for displacing and compacting material smoothly and evenly while producing a cylindrical hollow core through the construction blocks, including: (a) a continuous smooth cylindrical outer surface having a constant radius about a center axis equal to the radius of said circular aperture; (b) a curved vane projecting axially outward from one end of the cylindrical surface to an outer edge lying within a plane perpendicular to the axis of the smooth cylindrical surface; (c) said curved vane having a radial edge that intersects said outer edge and is an extension of said cylindrical surface; (d) the vane presenting a transversely curved convex face in the intended direction of rotation of the rotor; (e) the face of the vane having a radial orientation at the center axis of the cylindrical surface and constantly receding from the direction of rotation spirally to a tangential orientation at the cylindrical surface; means for inserting and withdrawing the rotor relative to the mold interior through the circular aperture in the mold cover; and means operably connected to the rotor for rotating it about its center axis. ### Claim 6 (depends on 5) An apparatus for forming construction blocks from a mixture of cement and fibrous material as defined in claim 5 wherein the rotor includes a plurality of curved vanes. ### Claim 7 (depends on 6) An apparatus as defined in claim 6, wherein the vanes are configured to present an S-shaped outer edge. ### Claim 8 (depends on 5) An apparatus as defined in claim 5, wherein: the cylindrical surface includes a cone-shaped projection having a base centered about the center axis of the cylindrical surface; the base of the cone being congruent with the circumference of the cylindrical surface; the cone having an outside surface projecting outward from the end of the cylindrical surface to an apex intersecting the plane perpendicular to the axis of the cylindrical surface. ### Claim 9 (depends on 5) An apparatus for forming construction blocks from a mixture of cement and fibrous materials as defined in claim 5, wherein said confining mold includes a movable pallet facing opposite the mold cover; said pallet containing an aperture in alignment with the rotor for venting the hollow cores of the block when withdrawing the rotor. ### Claim 10 (depends on 5) An apparatus as defined in claim 5 wherein the mold cover is horizontal and the center axis of the rotor is vertical.