Abstract: An expandable polystyrene composition in the form of expandable beads, comprising by weight (1) 100 parts of a styrene polymer, (2) from 2.2 to less than 4.0 parts of at least one blowing agent, and (3) from 0.01 to 0.4 part of at least one plasticizing. The composition is particularly useful for manufacturing medium density expanded moulded polystyrene objects, particularly with a density from 40 to 190 g/l. A process for manufacturing such objects,is provided, together with pre-expanded beads with a buld density of 40 to 190 g/l, containing by weight (a) 100 parts of a styrene polymer, (b) from 0.5 to less than 3.0 parts of at least one blowing agent, and (c) from 0 to 0.4 part of at least one plasticizing agent.

Abstract: The invention relates to an expandable polystyrene composition in the form of expandable beads, comprising by weight (1) 100 parts of a styrene polymer, (2) from 2.2 to less than 4.0 parts of at least one blowing agent, and (3) from 0.01 to 0.4 part of at least one plasticizing. The composition is particularly useful for manufacturing medium density expanded moulded polystyrene objects, particularly with a density from 40 to 190 g/l. The invention also relates to a process for manufacturing such objects, employing an expandable polystyrene composition in the form of beads containing by weight (1) 100 parts of a styrene polymer, (2) from 2.2 to less than 4.0 parts of at least one blowing agent, and (3) from 0 to 0.4 part of at least one plasticizing agent. The process comprises (i) a pre-expansion stage by heating the expandable beads so as to form pre-expanded beads with a bulk density of 40 to 190 g/l, (ii) a stabilization stage by contacting the pre-expanded beads with a gaseous medium at 0 to 40° C.

Abstract: In a device for positioning a tool in a working area wherein two spaced parallel horizontal guide tracks are provided and a guide slide is movably supported by each guide track, a coupler link is supported on each guide slide so as to be pivotable about a vertical pivot joint axis and the coupler links are joined to each other pivotably about another joint having an axis parallel to the vertical pivot joints of the coupler links, and a spindle extends from the other joint of the coupler links in alignment with the axis thereof so as to be linearly adjustable and is provided with a tool. The spindle with the tool is position-adjustable by linear movement of the guide slides along the tracks whereby the tool supported by the coupler links which are longer than the distance between the two guide tracks can cover also areas at opposite sides of the two parallel guide tracks.

Abstract: In a method of transferring semiconductor chips from a substantially flat wafer having an active side with a plurality of individual semiconductor chips formed thereon and a support side opposite the active side to a receiver, and the wafer is attached with its support side by way of an adhesive sheet to a support structure and is cut into segments corresponding to the individual semiconductor chips so that the semiconductor chips are individually supported on the adhesive sheet with their active sides exposed and facing away from the adhesive sheet, the support structure is moved with the individual semiconductor chips into a position wherein a particular semiconductor chip to be removed is positioned in a removal location above a receiver and the adhesive sheet is pushed downwardly at the particular semiconductor chip location so as to release the particular semiconductor chip and transfer it with the active side thereof onto the receiver.

Abstract: In a method of transferring semiconductor chips from a substantially flat wafer having an active side with a plurality of individual semiconductor chips formed thereon and a support side opposite the active side to a receiver, and the wafer is attached with its support side by way of an adhesive sheet to a support structure and is cut into segments corresponding to the individual semiconductor chips so that the semiconductor chips are individually supported on the adhesive sheet with their active sides exposed and facing away from the adhesive sheet, the support structure is moved with the individual semiconductor chips into a position wherein a particular semiconductor chip to be removed is positioned in a removal location above a receiver and the adhesive sheet is pushed downwardly at the particular semiconductor chip location so as to release the particular semiconductor chip and transfer it with the active side thereof onto the receiver.

Abstract: A device for positioning a tool within a predetermined working area includes two guides which are parallel to one another and run in a first coordinate direction, and on which in each case a guide slide is mounted in a longitudinally adjustable manner. The guide slides are connected by a supporting structure which carries the tool and which also permits a movement of the tool in a second coordinate direction. It is connected to the guide slides so as to be movable about in each case a first or second joint axis, respectively, parallel to a third coordinate direction. It includes two coupler links which are connected to one another by a third joint axis parallel to the first and second joint axes. Coaxially to this third joint axis, the supporting structure is provided with a spindle which carries the tool and is adjustable linearly in the direction of the third coordinate direction and independently thereof by a rotation angle about the third joint axis.

Abstract: A workpiece-carrier changeover apparatus removes a workpiece carrier from a storage unit and moves it in a first direction into a buffer storage position. Any workpiece carrier in a supply position is then moved back toward the storage unit either simultaneously with that movement or thereafter so that the workpiece carrier in the buffer storage position can be moved into the supply position.

Abstract: In a chip feed device and a method of feeding semiconductor chips from a substantially flat wafer having a plurality of semiconductor chips, the wafer is arranged with the active side facing downward, the wafer is positioned relative to the removal position so that a semiconductor chip to be removed is arranged above the removal position, then the semiconductor chip to be removed is removed downward from the wafer, and is transported from the removal position to a transfer position.