摘要:
Procédé de fabrication d'une section de bloc de plastique mousse expansé et de combinaison de cette section avec une section préfabriquée ou partiellement fabriquée comportant les étapes suivantes: chargement d'une cavité de moule dont une extrémité est déterminée par une surface de la section antérieure avec des perles de plastique pouvant être expansé, amorçage de l'expansion et fusion des perles pour créer une masse de perles susceptible de cohésion mais dans une grande mesure non expansée, obturation de la section antérieure dans la cavité de moule pour comprimer une zone de la masse susceptible de cohésion proche de ladite extrémité, augmentation de la température et de la pression dans la cavité de moule pour achever le procédé d'expansion et de fusion et pour comprimer la zone terminale de la section antérieure afin d'amener son extrémité essentiellement en une position non obturée, abaissement desdites température et pression et éjection de la section de bloc nouvellement fabriquée de la cavité de moule. Est également décrit un appareil pour réaliser ce procédé.
摘要:
Gang saws and other cutting apparatus having oscillating cutters for cutting workpieces into slices. The apparatus has two elongate spaced apart cutter supports (12, 13) which are driven to oscillate 180° out of phase with each other. Two sets of cutters (11) are connected to the supports. For a suitable workpiece the cutters may be of a hot wire type. Each cutter (32) of one set (11) is connected to the first support (13,47) by a resiliently extensible connector such as a spring (34) and to the second support (12, 47) by a non-extensible connection. Each cutter (32) of the other set (11) is connected to the second support (12, 47) by a resiliently extensible connector (35) and to the first support (13,47) by a non-extensible connection. Desirably the cutters of one set alternate with cutters of the other and all cutters are coplanar. Movement of cutters of each set in opposite directions tends to cancel the local influence of cutters on the workpiece. Moreover whole frames of cutters may be removed and replaced, facilitating reprogramming of the apparatus in terms of spacings between cutters.
摘要:
A method of making an expanded plastics foam block section and uniting it with a prior made, or partly made, section comprising the steps of charging a mould space of which one end is defined by a surface of the prior section with expandable plastics beads, initiating the expansion and fusion of the beads to create a cohesive but largely unexpanded mass of beads, obtruding the prior section into the mould space to compress a zone of the cohesive mass adjacent to the said one end, increasing the temperature and pressure in the mould space to complete the expansion and fusion process and to compress the end zone of the prior section to bring its end substantially to its unobtruded position, lowering said pressure and temperature, and ejecting the newly made block section from the mould space. Apparatus for performing the method is also disclosed.
摘要:
Plastics foam scrap is drawn by an air stream through a three-stage disintegrating apparatus. Each stage includes a plurality of moving interdigitating pins 19, 20 and the pin spacing and a passage dimension of each stage decreases from stage to stage thereby reducing the material to its component beads.