A blow-molded unitary structure includes a panel having first and second panel walls and a generally hollow interior between the first and second panel walls. The structure also includes one or more different types of strengthening elements monolithically formed with the panel and across a substantial portion of the panel to enhance the strength of the structure. A strengthening element can be a depression recessing from the second panel wall toward an interior of the panel, a protrusion protruding from the second panel wall toward an exterior of the panel, a rib protruding outwardly toward the exterior of the panel and a trench formed by side walls of adjacent protrusions.

A multi-layered pressure packaging comprises a first container including a lockable neck portion followed by a body part and a bottom part, obtained from a non-foamed thermoplastic material by stretch blow molding, and a first layer at least enclosing the body part and/or bottom part of the first container. The first layer comprises foamed material, and the foamed material layer is foamed in place with an outer enclosure applied over and around the first container defining a free space in between, and foamable material introduced and foamed between the first container and the outer enclosure in the free space, obtaining the foamed material layer. A second layer is applied on the outer surface of the foamed layer for keeping the foamed layer and the first container together. Methods are provided for manufacturing a multi-layered pressure packaging according to an embodiment.

A blow-molded plastic frame of a portable collapsible sign includes a first outer portion, a second outer portion spaced apart from the first outer portion, and a pattern of structural stiffening features formed in the first and second outer portions. The pattern comprises rows and columns of first depressions extending from the first outer portion into a hollow interior portion between the first and second outer portions, and rows and columns of second depressions extending from the second outer portion into the hollow interior portion. Each first depression has a first floor comprising three first arms having rotational symmetry. Each first arm is rotated from another first arm by 120 degrees. Each second depression has a second floor comprising three second arms having rotational symmetry. Each second arm is rotated from another second arm by 120 degrees. The first floor of each first depression is aligned with the second floor of an adjacent second depression.

A blow-molded unitary structure includes a panel having upper and lower panel surfaces and a ridge extending downward beyond the lower panel surface. The ridge includes a first side surface, a second side surface, and a lower ridge surface joined with the first side and second side surfaces of the ridge. The ridge further includes a plurality of depressions formed at one or more of the first side surface, second side surface and lower ridge surface. The plurality of depressions enhances the strength of the ridge, and the ridge in turn enhances the strength of the structure.

A blow-molded unitary structure includes a panel having first and second panel walls and a generally hollow interior between the first and second panel walls. The structure also includes a plurality of depressions, or at least one ridge, or both the depressions and ridge to enhance the strength of the structure. The plurality of depressions is monolithically formed with the panel, recessing from the second panel wall toward the first panel wall. A depression has a side wall composed of first and second segments. Cross-sectional-wise, the first and second segments have different widths and thus collectively forms a step between the first and second segments. A ridge is also monolithically formed with the panel and includes a section, at which the width of the ridge varies along the height direction of the ridge.

A structure, such as a tabletop, may be constructed from plastic, such as blow-molded. The tabletop may include an upper surface, a lower surface, and a hollow interior portion disposed between the upper surface and the lower surface. A lip may extend downwardly relative to the lower surface of the tabletop, and the lip including an outer surface and an inner surface. A plurality of supports may be disposed in the inner surface of the lip, and a plurality of joints may be disposed in the inner surface of the lip. A joint may be disposed between adjacent supports. A distal portion of the lip may include a compression edge. A lower portion of the supports may contact the compression edge, and/or a lower portion of the joints may contact the compression edge.

A blow-molded unitary structure includes a panel having first and second panel walls and a generally hollow interior between the first and second panel walls. The structure also includes one or more different types of strengthening elements monolithically formed with the panel and across a substantial portion of the panel to enhance the strength of the structure. A strengthening element can be a depression recessing from the second panel wall toward an interior of the panel, a protrusion protruding from the second panel wall toward an exterior of the panel, a rib protruding outwardly toward the exterior of the panel and a trench formed by side walls of adjacent protrusions.

A segment for a Scruton helix includes: a segment body, a coupling device on the segment body for coupling the segment to a further segment for the Scruton helix, a push-on device on the segment body for coupling the segment to a rope. Also disclosed are a system for a Scruton helix, a Scruton helix, a tower for a wind turbine, and a method for mounting a Scruton helix.

An apparatus for making hollow, form-in-place gaskets is disclosed. The apparatus includes a nozzle and a forming surface. The nozzle comprises an extrusion orifice for extruding a gasket onto the forming surface. The apparatus further includes means for the nozzle to separately communicate with an air supply and a liquid elastomer supply. The nozzle configuration maintains the separation between the supplied air and the supplied liquid elastomer proximate to the extrusion orifice.

A blow-molding plastic bubble-generating device is provided, including a board-like shell body. The board-like shell body is formed through blowing a hollow embryo placed in a mold, the hollow embryo is blown and expanded, the hollow embryo is penetrated through by a plurality of needle posts on an inner wall of the mold to form the board-like shell body, the board-like shell body is integrally formed and hollow and has a shell wall which completely and continuously surrounds the board-like shell body, and the shell wall has a plurality of through holes.