Abstract: A baking oven comprising a hot-air circulating heating system by which hot air is heated and circulated through a baking chamber from a heating and circulating device arranged above the baking chamber. The heated air contacts the articles to be baked which are present in a multi-tier rack in the baking chamber. The baking chamber is defined by a housing which is formed of several sections and includes a cover, a floor and vertical walls. The walls are provided with insulation which is covered by a cowling. In the front wall is an opening which extends from the floor to the cover for the introduction and removal of the rack. The opening can be closed by a door. The housing is composed of a plurality of segments of the same outer contour which are stacked on one another, the uppermost segment containing the cover and the heating and circulating device, the lowermost segment containing the floor, the vertical walls being formed by at least two segments.

Abstract: A baking oven heated by circulation of hot-air comprising a baking compartment with a turntable at the bottom thereof adapted for receiving a multiple rack cart which carries the material to be baked and which is rotated around a vertical axis. The turntable is provided with a drive gear therebelow coupled to a chain which in turn is coupled to a pinion on a vertical shaft extending outside the baking compartment and driven by a drive motor. A chain box surrounds the chain and includes a portion extending outside the baking compartment which is air-tight to prevent escape of vapor thereat from the baking compartment. The vertical shaft extends into the air-tight portion of the chain box via a seal.

Abstract: An article is subjected to a treatment which causes one part thereof to become substantially more brittle than the remainder thereof. One manner of accomplishing this is to cool the article to low temperatures. Either during or subsequent to this treatment the article is subjected to an action which effects separation of the embrittled part from the remainder of the article. This may be achieved by impacting the article, by exposing the article to ultrasonic waves or, in the event that the embrittled part or the remainder of the article is composed of a ferrous substance, by exposing the article to a pulsating magnetic field. A preferred application is to composites consisting of a metal and a synthetic resin where cooling of the article embrittles the synthetic resin. One form of an arrangement for carrying out the method includes a hollow, rotatable cylinder having impacting masses such as steel balls accommodated therein.