| Characterized by the advantages of both forging hammer and crank-eccentric press, the screw press, whose blow force is confined to the frame and has no fixed bottom dead center, find an important application in the field of precision forging and closed die forging. However, the conventional screw press, whose flywheel rotates first in one direction and then in the opposite direction, tends to create unnecessary energy waste, and is difficult to increase its stroke rate. The clutch screw press is a new type and high performance machine, whose flywheel rotates in one direction, and the clutch would be disengaged automatically as the blow force or the travel of ram reaches the preset level, switching off the energy transmission from flywheel to the screw, thus, there would be significant increase in energy efficiency and stroke rate of the press. The clutch screw press, brought into existence just about 20 years ago, with driven parts of small moment-of-inertia, is worth for the investigating. Concentrating on the disengagement performance, which is the key to giving a full play to the advantages of the clutch screw press, our research has achieved results as follows1. Based on the dynamic equations of valve, the flow continuity equation of oil, differertial equation of screw motion and integration equation of friction work of clutch, a thorough analysis is conducted on the disengagement process of clutch, forming mathematic models for the relation of preset oil pressure of valve to various phenomena during clutch disengagement, for the relations between moment-of-inertia of flywheel and screw, and for the relation among structure of screw pair, state of friction pair, stiffness of machine frame and resistant force of workpiece, and establising the state equation of disengagement of various clutches, by which a foundation is laid for analysis of disengagement performance and for optimization of prarmeters. The analysis reveals that the disengagement performance of clutch bears a...
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