Abstract: The invention relates to a process for producing foamed polyolefin-based plastics blocks by first crosslinking a matrix comprising a) from 51 to 97% by weight of one or more polyolefins, selected from the group consisting of polyethylene and ethylene copolymer, b) from 3 to 20% by weight of a foaming agent, using &bgr;-radiation of energy >6 MeV. The thickness of the matrix is from 25 to 45 mm. The radiation dose is from 20 to 150 kJ/kg. During the irradiation, atmospheric oxygen is at least substantially prevented from reaching the surface of the matrix. After crosslinking, the crosslinked matrix is foamed by heating to a temperature >160° C. and decomposing the blowing agent.

Abstract: A standing umbrella includes an upright pole, a top affixed to the upper end of the upright pole, a slide member displaceably mounted on the upright pole, at least four tensioning struts having free outer ends and inner ends linked to the slide member at respective pivots, a flexible cover affixed to the tensioning struts, and flexible carrier elements extending between the top and the tensioning struts. Displacement of the slide member towards the lower end of the upright pole moves the tensioning struts into positions in which they almost extend perpendicularly to the upright pole, diametrically opposite ones of the tensioning struts enclosing an angle of less than 180.degree., whereby the umbrella is opened, and displacement of the slide member towards the upper end of the upright pole causes the umbrella to be closed. A flexible member extends between the tensioning struts and is affixed thereto for limiting the opening movement of the tensioning struts.

Abstract: A closing element for rooms, such as buildings, containers, superstructures of vehicles or the like, which can be rolled up and covers a two-dimensional area. The closing element is of a flexible material which can be rolled up and is reinforced transversely of its rolling direction by bending-resistant reinforcement layers which increase the transverse stiffness and which are embedded on both sides of a core zone within the closing element. At least the core zone of the closing element is of a shifting-resistant material of middle-soft formulation of approximately 70-85 shore A, and/or textile and/or metal flakes or fibers are mixed into the material of the core zone.

Abstract: The supporting body of an instrument is joined to a casing by means of ribs fitting into guideways angularly spaced around a centerline of the supporting body. Thereby, small clearances between the ribs and guideways in a direction parallel to the casing wall surfaces are effective in limiting play at right angles to the casing walls, where much greater clearances must be provided. The casing may expand or shrink freely without exerting strains on the supporting body that could interfere with the proper function of the instrument, due to the large radial clearances between the ribs and guideways.