Combined compression roller screw nut fixing device of tire builder

The utility model relates to a combined compression roller screw nut fixing device of a tire forming machine. A locating sleeve is a semi-cylindrical sleeve.,and the inner diameter of which is the same as the outer diameter of a screw nut. A shoulder with a semi-circular ring is fixed on one end of the locating sleeve. The plane of the semi-circular ring and the center line of the semi-cylindrical sleeve are vertical. A through hole is arranged on the semi-circular ring of the shoulder for fixation. The locating sleeve is positioned under the screw nut and is buckled at the screw nut. The locating sleeve and the screw nut are connected by a fixed key to be prevented from rotating. A clamp plate is arranged on the end surface of the shoulder of the locating sleeve. A bolt is arranged on the lateral face of a case body after penetrating through the clamp plate and the locating sleeve. The outer diameter of the screw nut is smaller than the inner diameter of each of bearing seats on both sides of a screw rod. The utility model has the advantages that the disassembly is convenient, when the screw nut needs to be changed, the locating sleeve and the screw rod on a slide frame are removed, the screw nut can be taken off from the slide frame and changed, the utility model shortens the time for changing, two skilled repairing workers spend half an hour finishing change, and as a result the utility model improves the utilization rate; a wheel frame, a connecting rod, a polished rod, a worm rod, etc. need not to be demounted frequently, so the attrition is reduced and the durability of the device is extended.