Abstract: In an apparatus for the production of articles from a planar web of thermoplastic material, having heating, hot shaping and punching devices, a web conveying mechanism for stepwisely transporting the web along the substantially planar path through the apparatus includes a plurality of driven stationary conveying units arranged at opposite edges of the web along the path thereof, each conveying unit including a driving wheel and a cooperating free wheeling supporting roller arranged opposite to each other and having their axes of rotation extending substantially parallel to each other and to the plane of the web, the driving wheel having a wedge-like converging circumference with a toothed circumferential edge and connected to a driving mechanism which synchronously drives the driving wheels, and the free wheeling supporting roller having a cylindrical circumference supporting the web in an adjustable position relative to the driving wheel, such that the toothed circumferential edge partly penetrates the web a

Abstract: Method and apparatus for storing of heat by use of the heat of fusion or crystallization of a liquid-solid storage medium. A conventional crystallization roller rotates with its circumference partially immersed in the melted storage medium. Heat receiving liquid circulated through the drum to a point of use receives heat from melted storage medium in contact with the drum, whereby such storage medium solidifies on the surface of the drum. The drum rotates the solidified storage medium past a fixed scraper which transfers the solid storage medium to a heat exchanger. Heat supplying liquid circulating through the heat exchanger imparts its heat to, and melts, the scraped-off storage medium which returns to the storage medium reservoir and brings with it the heat obtained from the heat supplying liquid.