Abstract: A device for producing expansions and in particular inside grooves, such as packing grooves, in plastics pipes and pipe components. The device comprises a form ring for shaping the inside profile of the expansion, the circumference of which ring is divided into two groups of segments, which can be shifted radially inwards so that the form ring can be disassembled and removed from the pipe after shaping of the expansion, a mandrel that can be shifted axially through the form ring, a core body that surrounds the mandrel and in relation to which the mandrel can be shifted axially, and two groups of first inclined faces, in connection with the mandrel, one face group for each segment group, so as to produce radial movement of the segments, for example by forcible controlling, whereby the first group of inclined faces is arranged axially at a distance from the second group of inclined faces.

Abstract: A process and portable apparatus for forming individual or multiple reinforced concrete, hollow core units of a modular building structure in interconnected side by side and/or high rise relationship which apparatus may be sufficiently collapsed to allow for easy removal from the formed and cured hollow core unit to again be used to form additional subsequent, interconnected, hollow core units of the building structure.

Abstract: A flexible printing plate is separated from the inner surface of a curved matrix after formation of the plate in a mold by first moving the ends of the plate inwardly away from the matrix, while maintaining the center of the plate in stationary contact with the matrix, and then moving the center of the plate inwardly away from the matrix, while maintaining the ends of the plate away from the matrix. The matrix is held in an outer mold half, and the printing plate is formed in a mating inner mold half having a center section wih sloping side surfaces that converge toward the outer mold half, a first end section having a side surface contiguous to one sloping side surface of the center section, and a second end section having a side surface contiguous to the other sloping side surface of the center section.

Abstract: Apparatus for molding, in a single integrated operation, a tubular part having an internal recess which may take the form of a groove extending completely around the inside of the part for receipt therein of an O-ring or the like. The apparatus comprises a core assembly having a longitudinal axis, and base means movable along the axis and defining an annular outer mold surface for forming of the interior wall of the tubular part. The core assembly further includes a plurality of groove-forming segments carried on the base means adjacent to the annular surface and movable between first contracted positions and second expanded positions. When the segments are in the contracted positions they do not extend radially outwardly of the annular surface, and the surface and segments may be withdrawn from the molded tubular part by movement along the longitudinal axis.

Abstract: A molding device including a rigid container defining a molding chamber and a mating collapsible member with walls and a floor and of a normal size and shape to mate in the rigid container and define a molding space between the container and the collapsible member; the collapsible member includes means to collapse it through a first stage of movement of withdrawal of the walls inwardly from a molded object and a second stage of movement of withdrawal of the floor axially upwardly away from the container and a molded object.

Abstract: In an expansible core, a plurality of first plate segments are moved radially outwardly by means of a conical portion on an operating rod which is moved axially along the longitudinal axis of the core. A plurality of second plate segments are moved axially by the operating rod into the plane of the first plate segments and then expanded outwardly into the spaces between the first plate segments. First and second retraction means are also provided on the operating rod and are engageable respectively with the first and second plate segments to retract the plate segments from their expanded positions upon axial movement of the operating rod in the other direction.

Abstract: A tube expander apparatus having an axially displaceable central shaft, a plurality of convex expander shoes in succession circumferentially around the shaft, and pivoted linkage arms between the shaft and the expander shoes and including:A. first linkage arms pivoted to the expander shoes and to a fixed support collar which slidably passes the shaft;B. and second and third linkage arms which are pivoted to the expander shoes above and below the latters' axial midpoint and to collars fixed to the shaft.