| 摘要 |
621,956. Dielectric heating. GOODRICH CO., B. F. March 6, 1946, No. 7025. Convention date, March 26, 1945. [Class 39(iii)] Dielectric vulcanisable material is surrounded by freely flowable dielectric material in the form of finely divided solid particles having dielectric heating properties closely similar to the material being treated, and is passed through a high frequency field. In a preferred apparatus for the continuous vulcanisation of an extruded rubber stock, the material 12 is led from the extruder 10 through elongated electrodes 18 and 21 by an endless belt 22 driven by a motor 25 via a gear reduction box and sprocket chains. The stock is surrounded with powdered soapstone 33 by a hopper 32, which also fills completely the remaining space between the electrodes. After passage between electrodes the powdered material falls into a hopper 34 and is returned to a delivery hopper 32 by a conveyer belt 35, the powder being kept, if required, at its elevated temperature by a heating coil (not shown). A brush 47 cleans off surplus powder, and the material is then immersed in a tank 51 for washing and spraying by jets 57. Finally the stock is led to a drying belt (not shown) and to winding means. Apparatus for treating individual articles such as washers and stampings is also described. Specification 599,935 is referred to. |
