Abstract: A clam shell rotational moulding machine of a type including a housing having a base portion with a flat base and four upstanding sides and a cover portion with a top and four depending sides can be moved from a fully closed position in which the top and base co-operate to form an enclosed housing to an open position in which the cover portion is lifted and a front one of the side walls of the base is opened to a horizontal position above a pivot axis across the bottom of the front wall. A spindle arm assembly normally mounted during the moulding process within the housing and extending into the housing through the side walls can be moved from the normal position to an unloading position. The spindle arm assembly is mounted upon a cantilever arrangement carried by a rigid frame mounted on the front door. Opening of the front door thus moves the spindle arm assembly and attached moulds to the unload position substantially vertically above the horizontal surface of the front door.

Abstract: Rotary forging of a component from powder is accomplished in a single forging operation without any sintering or other processing by firstly pressing the powder in a closed die situation to produce an initial compressed form and then subjecting this compressed form to a rotary forging process.

Abstract: A rotational molding machine having an oven enclosed by a pivotable top clam shell cover, front entry doors for interior oven access, and a spider arm and drive spindle which is supported by bearing members on opposite walls of the oven for removable mounting thereon.

Abstract: A process for producing a hollow plastics article, which comprises introducing a polymerizable composition in the hot state into a sealed hot mould, immediately setting the mould in motion by imparting to it a second movement of rotation about a second axis and a third movement of oscillation about a third axis which is perpendicular to the second, so that the composition is applied to the inner walls of the mould, and polymerizing it herein to form a hollow article. The improvement comprises setting the mould in motion by further imparting to it, simultaneously to the second and third movement, a first horizontal movement which has, in a horizontal plane, two components in two directions perpendicular to each other.

Abstract: Disclosed is an improved packerhead or drycast concrete product forming apparatus and method for making a concrete product therewith. The apparatus typically includes a mold having a lower curing pallet, a platform for supporting said mold at the pallet, and a vibrator table having a vibrator ring for association with said curing pallet. The improved apparatus of the present invention preferably comprises a vibrator ring having selectively engageable (and disengageable) means to rigidly connect the vibrator ring to the curing pallet when said vibration means is activated. The preferred vibrator ring selectively engageable means comprises electromagnet means and the preferred product of the process comprises concrete pipe.

Abstract: A method of manufacturing a beadless flexible member for an airspring having a fully molded non-tubular shape. An axially segmented mold with tapered circular end bores is used with conically tapered end plugs which sealingly compress an uncured preform of the flexible member between the conical plugs and the tapered circular end bores. Compressed fluid is injected into the interior of the preform to radially expand it to the desired molded shape. At a rate determined by the radial expansion of the preform, the annular segments of the mold are axially moved together to accommodate the axial foreshortening of the preform during its radial expansion. After full axial closure of the mold, heat and pressure are applied to vulcanize the preform. The beadless, fully molded flexible member may be used for airsprings requiring zero pressure roll capability.

Abstract: A rotational molding machine having an oven enclosed by a pivotable top clam shell cover, front entry doors for interior oven access, and a spider arm and drive spindle which is supported by bearing members on opposite walls of the oven for removable mounting thereon.

Abstract: A method and an apparatus for compacting newly poured comparatively dry concrete or similar porous plastic raw materials (6) with a direct mechanically coupled 3-mass oscillatory system where the raw material in its confined form is vibrated and compacted from both sides by two vibrating planes with synchronized directional vibrations in phase opposition. Only one vibrating plane (M1) includes synchronized directional vibrators (4). Its other part (M3) is elastically coupled with (M1) by spacer means (8) (M2) arranged between a spring system (7) being so dimensioned that the parts is dynamically balanced whereby the two parts (M1) and (M3) oscillate in phase opposition close to or at the 2nd natural frequency of the system with a dynamic amplification of the amplitudes in relation to the impulses imparted from the vibrators (4) at the same time while (M2) is stationary. During the process (M1) and (M3) are carried towards each other by (M2) as the raw material is gradually compacted.

Abstract: A method and apparatus are provided for spreading monomer mixture in molds for the centrifugal casting of contact lenses, wherein the said molds containing a monomer mixture are rotated around their axis with the frequency 0.5 to 5 revolutions per minute and, at the same time, the axis of molds is periodically tilted between extreme positions, the angle to the vertical direction of which is in the first extreme position 30.degree. to 60.degree. and in the second extreme position 70.degree. to 100.degree. and the frequency of tilting is twice to ten times lower than the frequency of rotation.

Abstract: There is disclosed apparatus for rotationally casting a plastic liner for a pressure vessel having a metal access fitting molded therein. The apparatus includes a rotational casting arm having a mold supporting surface and adapted to be rotated about orthogonal axes. A hollow mold having a mold cavity surface conforming to the outside surface of the liner to be molded is removably attached to the mold supporting surface together with a metal access fitting. The metal access fitting has a longitudinal axis aligned with one of the orthogonal axes and has at least a first surface portion extending into the mold cavity. The first surface portion and the surface of the mold cavity are coated with plastic upon mold rotation to form the plastic liner.

Abstract: The present invention consists of a spindle arm for use in batch-type rotational plastic molding machines. The invention herein includes two cylindrical arms, one end of each arm attached to a gear housing and extending therefrom in a common axis. The gear housing contains gears for providing connection between and transmission of rotation from, a driving shaft, extending from the gear housing, to a driven shaft, extending through the gear housing in an axis perpendicular to the driving shaft. The end of the driving shaft extending from the gear housing is attached to a drive sprocket, the sprocket providing for releasable connection to a drive motor of the molding machine. The driving shaft is contained within one of the cylindrical arms and is rotatably supported therein. The other cylindrical arm is attached, on the end extending from the gear housing, to a second drive sprocket for providing releasable connection to a further drive motor of the molding machine.

Abstract: A rotary molding apparatus is described, including a heating chamber, cooling chambers and supports for molds which melt and cast workpieces of plastic. The cooling chambers can be arranged circularly around the heating chamber which is disposed at the center, or the heating chamber can be movable such that an opening thereof can be selectively aligned to one of the cooling chambers. The molds can be moved via the supports from a cooling chamber to the heating chamber and back again. This apparatus optimizes component utilization and minimizes cycle times.

Abstract: A packerhead concrete pipe making machine having a rotatable packerhead operable to form a concrete pipe in an upright cylindrical mold about a wire cage. The packerhead has a plurality of rollers rotatably mounted on a circular plate operable to pack concrete into a cylindrical shape in the mold. Each roller has an outer sleeve of elastic rubber material. A cylindrical wall secured to the plate supports an annular troweling member operable to finish the inside surface of the concrete pipe.

Abstract: A method of rotationally molding hollow articles from cross-linkable polymeric material wherein the mold and molding material are simultaneously revolved about two nonparallel axes while being heated to fuse and cross-link polymeric material. When the polymeric material is partially cross-linked the mold containing the hollow article is opened at at least one location to admit heated air circulated therethrough to facilitate cross-linking of the inner portion of the molded tubular article and produce a smooth inner surface therein. Also disclosed is apparatus for performing the molding method of the invention.

Abstract: A method of rotationally molding hollow articles from cross-linkable polymeric material wherein the mold and molding material are simultaneously revolved about two nonparallel axes while being heated to fuse and cross-link polymeric material. When the polymeric material is partially cross-linked the mold containing the hollow article is opened at at least one location to admit heated air circulated therethrough to facilitate cross-linking of the inner portion of the molded tubular article and produce a smooth inner surface therein. Also disclosed is apparatus for performing the molding method of the invention.

Abstract: An apparatus for centrifugally casting a rectangular access floor panel includes a turntable, a drive for rotating the turntable about a generally vertical axis in a generally horizontal plane, and a mold clamped to the turntable. The mold is vibrated during rotation to insure void-free distribution of a lightweight concrete mixture throughout a metal pan retained within the mold. A hopper and an auger feed the concrete mixture to the mold through a sprue. The mold retains corner pads and silencer buttons. The corner pads cooperate with pedestal heads to eliminate the need for stringers.

Abstract: Rotational molding apparatus and methods for rotationally molding castable material such as polymers and other materials. In one form, a shuttle or wheeled carriage containing a mold fixture for holding one or more molds, which fixture is both pivotable and rotatable on the carriage, is operable to move along a fixed path into and out of an oven and a cooling chamber. Two of such mold fixture containing carriages may be automatically moved between the oven and one or more cooling chambers, alternately to permit the oven and cooling chamber or chambers to be operated substantially all of the time during an operating shift.

Abstract: The invention is concerned with a method for continuous slide-casting of large-size concrete objects or corresponding elements for compacting high-viscosity casting mix. The slide-casting mould (33) comprises a bottom plane (34), side walls (38, 39) of the mould, as well as means (37) for pressurizing the casting mix mechanically. According to the invention, before the parallel side walls (44, 54) at the outlet end of the slide-casting mould (33), within the casting line concerned, walls or wall portions (40 to 43, 50 to 53) are provided as fitted to each other or to their corresponding portions, provided as pairs, as pivotable always in the same direction around substantially vertical shafts (45 to 49, 55 to 59) included in their planes. The moving parts of the side walls (38, 39) may be displaced in pairs in the lateral direction, relative the casting direction, e.g., by means of cylinder-piston devices (61 to 63).

Abstract: A method and apparatus for leveling a batch of pulverulent constituents in making a vitreous cellular material. A screen structure having at least one substantially flat screen layer is impressed down into and through at least a portion of the batch of pulverulent constituents. The screen structure is vibrated horizontally in a circular orbital motion while impressing the screen structure down into and through at least a portion of the batch of pulverulent constituents.

Abstract: Method and apparatus for forming fine, relatively dry particles into shaped refractory, ceramic and porcelain preforms or similar compacted articles by confining the loose particles in a shaped enclosure having at least one movable, preloaded side to maintain the particles in a loose but contiguous mass, accelerating the mass particles and at least a portion of the mold in such a manner as to induce a positive or negative acceleration of the mass of a magnitude at least 25 to 50 G's, depending upon the particle composition, and preferably in the range of 500 G's to 5000 G's, or greater, again depending on the particle composition in order that each particle undergoes a force generating impact with adjacent particles to homogeneously compact and fuse the adjacent particles one to the other in a nonbridging manner.

Abstract: The invention relates to a process for the production of a contact lens, which comprises coating a tool made of an inert material, having a curvature corresponding to that of one of the optical surfaces of the lens to be produced, with a layer of solid polymer, and machining the outer surface of said polymer to the desired curvature of the second surface of said lens while supported by said tool, and to a tool for carrying out such process.

Abstract: A method and apparatus for spin casting a castable material into a cylindrical body. The method comprises the steps of rotating an elongated cylindrical body about its longitudinal axis, applying an extrudable uncured material as a continuous stream in helical fashion from one point in the body to another point, continuing to rotate the body until the material is leveled and at least partially curing the material while continuing to rotate the body. The apparatus comprises means for holding and spinning an elongated cylindrical body, and extruder means for providing a continuous stream of an extrudable uncured material in a desired fashion along the inside of the cylindrical body.

Abstract: Apparatus for filling flat molds for slabs and the like carried on a conveyor belt is disclosed. The molds are displaced by the conveyor belt from a filling unit to a finishing unit. The filling unit comprises a vibrating table imparting vertical vibrations to the mold and a distributor member extends transversely of the conveyor for spreading the molding material supplied immediately ahead of the distributor member in the mold at the filling station. Horizontal vibrations are imparted to the distributor member parallel to the path of movement of the conveyor belt. The finishing unit has a smoothing member to which horizontal vibrations are imparted. The smoothing member is reciprocated transversely of the path of movement of the conveyor belt.

Abstract: For the manufacture of oval dishes, a machine has two work supports arranged to rotate moulds eccentrically for clay on the moulds to be shaped into oval forms. At a first, spreading, station the clay is engaged by a pancake-type spreading roller which squeezes a piece of clay into an oval shape. The mould is transferred to a second, or finishing, station where a finishing roller rolls the clay to the desired configuration of the oval dish. The spreading roller is driven. The finishing roller may be driven or it may rotate freely, a brake being applied to the free roller, for the end of a finishing operation, to improve the surface finish of the ware.

Abstract: A concrete product making machine having a counter rotating packerhead assembly and a concrete supply control operable to maintain a desired amount of concrete in the mold above the packerhead assembly. The counter rotating packerhead assembly has a lower packerhead unit rotated in one direction by a motor and on upper packerhead unit rotated in an opposite direction by hydraulic motors mounted on the cross head of the machine. The upper packerhead unit located above the lower packerhead unit has a plurality of rollers and an annular trowel. The trowel has radially adjustable shoes which meter the flow of concrete to the lower packerhead unit. A control system responsive to hydraulic fluid pressure supplied to the hydraulic motors controls the operation of a concrete supply conveyor operable to deliver concrete to the chamber above the packerhead assembly. The control system includes a control valve assembly operable to regulate the supply of hydraulic fluid to a hydraulic motor operating the conveyor.

Abstract: An apparatus for forming concrete articles of uniform density, which includes means for forming concrete into the form of the articles, and means for sensing the density of concrete in each area of formation in the forming means as the article is being formed, comparing the sensed density to a preset density, and compensating for variation of the sensed density from the preset density responsive to such comparison, such that the density of concrete in each area of formation in the forming means as the article is being formed equals the preset density.

Abstract: Disclosed is a method and apparatus for forming indicia on the outside of a roto-molded plastic container during the roto-molding process wherein a template bearing a mirror image of the indicia is removably affixed to the interior wall surface of a mold.

Abstract: A method and apparatus for the rotational molding of thin-walled articles. The method is comprised of the steps of introducing a predetermined amount of plastic material into a mold, rotating the mold about a first axis at a predetermined speed, while simultaneously rocking the mold through a selective arc about a second axis which is normal to the first axis, heating the mold for curing the plastic material during the rotation and rocking, and cooling the mold and plastic material whereby the plastic material is molded to form a thin-walled object in conformance with the interior surface of the mold. The rotational molding apparatus is comprised of a heat insulating housing comprising a bottom half and a top half which may be disassociated for access to the interior of the housing. The interior of the housing contains a first frame which may be rocked about a first axis and a second mold-carrying frame which is attached to the first frame and rotates about a second axis normal to the first axis.

Abstract: An oval dish forming machine has two revolvable wheels each of which is supported on a structure permitting the wheel to move in an eccentric pattern so that discs of clay on carriers on the wheels may be formed in desirable oval shapes. One of the wheels comprises a first or spreading station where the disc of clay is subjected to a rolling extruding action of a cone-shaped roller which squeezes the clay against the carrier to form a desirable oval shape. The carrier and the initially shaped clay is then manually moved to a second or finishing station where a dumbbell shaped roller engages the clay shape on the carrier and rolls the excess clay from the shape to the desired configuration of the oval dish. The dumbbell shaped roller is stopped in the last revolution of the wheel so as to smooth the clay by a sliding action. Motion of the two shaping and finishing rollers is controlled to properly process and shape the clay so as to insure the removal of air and excess moisture therefrom.

Abstract: A rotational molding system is disclosed in which a pair of large boat molds carried on separate carriages are alternately heated in a double open-ended oven having opposing cantilevered side sections for receiving concentric drive arrangements wherein the molds may be driven about two perpendicular axes in a rocking or full rotational motion.

Abstract: A method for promoting the flow of a solidifiable liquid or molten material upon the surfaces of a body and particularly such a method applied to a process of rotational casting or molding requiring charging a mold cavity with the solidifiable liquid or molten material and rotating the mold about each of two mutually inclined axes with a speed that is progressively decreased substantially in accord with the progressive increase in viscosity of the solidifiable material.

Abstract: A mold apparatus for forming a molded article comprising a hollow body of a crosslinked polymer rotationally molded around a section of at least one piece of non-crosslinked conduit, which conduits protrude from said hollow body, made by attaching said conduits of non-crosslinked material at the desired location to the mold with said section being located inside a heated section of the mold so that the crosslinkable polymer during a rotational molding process is fused and crosslinked inside of the mold and around and in tight welding-type connection with said section, whereas the remainder of the piece or pieces of uncrosslinked polymer are heat-insulated, thus avoiding deformation or collapsing of these pieces.

Abstract: The apparatus comprises a double walled mould interior divided into two halves, a heat exchange exterior hollow envelope and a pressure-exchange compartment within the envelope surrounding the adjacent abutting surfaces of the rims of the two mould halves, heat-exchanges and pressure-exchanges producing means to rotate the apparatus on two axes, means to introduce a protective gas into the mould to avoid combustion of vapors and optional means cooperating between the heat-exchange and pressure-exchange means in the heating and cooling phases.The method includes controls of pressure and heat-exchange steps during the heating and cooling stages to avoid formation of bubbles, deformities and combustions, particularly when transparent plastic materials difficult to mould are used.

Abstract: An apparatus and process is disclosed for rotational molding. Rotational molding is a technique for the fabrication of parts from powdered thermoplastic material in which the thermoplastic material is placed within a hollow mold and the mold is rotated in a heated environment until the thermoplastic material fuses and coats the entire interior surface of the mold. Included in the apparatus is a holding mechanism for the mold and a power mechanism to provide the required rotational motion to the mold. The power mechanism provides for simultaneous rotation of the mold about two orthogonal axes and is displaced spatially from the holding mechanism. The holding mechanism is attached to a translating mechanism which positions the molds both internal to and external to a heating chamber such as an oven while keeping the drive mechanism external of the oven at all times.

Abstract: Method for making a doll's head, for use in conjunction with a suitable torso, which will excrete a fluid through the brow portion of the head for simulating perspiration, and a method for making the same. The doll head includes an exterior surface formed and contoured with human characteristics and including an interior cavity or reservoir for storing fluid. The head is formed of flexible plastic having a slit at the mouth providing a valve for filling the interior reservoir and a plurality of small measured holes or pores in the brow or forehead which permit the fluid to flow outwardly therethrough. The method includes the steps of heating a mold containing heat curable plastic and slush molding the plastic to attain the interior shape of the mold.

Abstract: A device and method for use in the art or craft of molding hollow artistic objects from thermoplastic molding material, such as wax. The molding device includes a frame with a vertical stationary, circular gear rack secured thereto. A crank driven shaft is journaled through the frame in a position concentric with the rack. A yoke-like mold carrier is secured to the end of the shaft for rotation therewith. A mold holder is, in turn, mounted on the mold carrier for rotation about an axis generally perpendicular to the crank shaft axis between the yoke arms of the mold carrier. The mold holder has a shaft projecting through one of the yoke arms of the mold carrier and is secured to and driven with a disc gear, which is enmeshed with the gear rack. As the crank is turned to rotate the mold carrier, the disc gear rides on the gear rack and rotates the mold holder.

Abstract: A mold for use in the slush molding of boots with eyelets includes a pair of narrow, elongated grooves on its interior surface at the front side edges of the mold for forming relatively strong, one-piece, single thickness eyelet stays. The mold is in the form of a boot-shaped shell for receiving heat-curable plastisol, and forming a skin including one-piece eyelet stays.

Abstract: There are disclosed a method and an apparatus for producing an elongated concrete member of a trapezoid cross section for use as a cross tie, i.e., a prestressed concrete member for fixing rails of railroads.

Abstract: A forming device and method is disclosed herein that is particularly useful for forming large parts of polyurethane material. The forming device includes a proportioner that meters relative amounts of materials through separate supply sources to a mixer where the materials are combined and then supplied to a mold, the mold being then rotated to displace the materials throughout the mold to form therefrom a part having a preselected shape. Where the materials to be combined are polyurethane components, the components are combined and quickly supplied to the mold to displace and cure the part while in said mold.