Device and method for preparing plastic material, in particular, thermoplastic material

Abstract

A device for preparing plastic material, in particular, thermoplastic material, comprises a receptacle (1) for the material, in which rotating tools (21) are provided to act onto the material which are supported by a support disc (9) and rotate about a vertical axis (8) of the receptacle (1). Driving of the support disc (9) is effected by a shaft (4) which passes through the bottom (3) of the receptacle (1) and is driven by a motor (5). The material is discharged from the receptacle (1) through a discharge opening (15) to which the housing (16) of a screw (17) is attached. The discharge opening (15) is provided within the same receptacle (1) and is situated below the path of rotation of the tools (21) and below the support disc (9). Additional moving tools (12) are provided within the same receptacle (1) below the support disc (9) which convey the material into the discharge opening (15). In this way a long dwelling time of the treated plastic material within the receptacle (1) is achieved so that constructive length and driving energy for the screw (17) are economized. A method for preparing such plastic material provides that the material is continuously treated within the same receptacle in two successive steps by meows of two sets of tools arranged one above the other. In the first step carried out by the upper set of tools, the material is pre-comminuted and/or pre-heated and/or pre-dried and/or pre-mixed. In the second step carried out by the lower set of tools, the same treatment is effected, but less intensively as compared with the first step. The material thus treated is supplied by the tools of the second step to a screw which discharges the material from the receptacle.

Dependencies are inferred from the claim text.