Rubber kneading machine

A rubber kneading machine comprising:

• two horizontal rolls, including an upper roll and a lower roll, disposed vertically close to each other through an intermediary of an adjusting device for allowing a gap between the upper roll and the lower roll to be freely adjusted;
• driving means for rotating the rolls;
• a screw extruder including a screw extruder main body having screws and configured to supply a rubber lump fed into a hopper at a proximal end to the rolls;
• a circulating mechanism for kneading and mixing rubber that is formed by feeding a rubber sheet that has left the rolls to the hopper, the circulating mechanism is constructed of a winding control means for selectively winding the rubber sheet onto the upper roll by differentiating rotational speeds of the upper and lower rolls by a variable speed motor or a decelerator, and carrying means for sending the rubber sheet coming off the upper roll to the hopper;
• an extrusion cylinder accommodating the screws, the extrusion cylinder is configured to be attached to and detached from the screw extruder main body and a driving mechanism thereof;
• roll frames configured to support the upper and lower rolls and a distal end of the extrusion cylinder and configured to be removable;
• and
• the driving mechanism configured to drive the roll frames and the extrusion cylinder toward or away from each other and to drive the extrusion cylinder and the screw extruder main body toward or away from each other.