Patent ID: 7066063

Claim:
A power transmission mechanism for a turret of a lathe, the turret including: (1) a shaft housing having first and second passages formed thereon; (2) a central shaft in the shaft housing; the central shaft having a first gear secured thereon; (3) a clutch fitted to the shaft housing; (4) a tool disk positioned next to the clutch and securely joined to one end of the central shaft; the tool disk being capable of moving together with the central shaft between a left position and a right position; the tool disk being engaged, and secured with the clutch when it is in the right position; the tool disk being disengaged from the clutch when it is in the left position; and (5) an air pressure power source connected to the first and the second passages of the shaft housing; the power transmission mechanism being used together with the air pressure power source for causing leftward and rightward movement of both the central shaft and the tool disk; the power transmission mechanism including: (1) a piston positioned next to the central shaft and in a first room of the shaft housing, which room communicates with the first and the second passages; the piston being capable of making the central shaft move in a same direction as the piston; and (2) a force multiplier unit including: (a) a support ring securely disposed around the central shaft in the shaft housing; the support ring being formed with a plurality of spaced sloping trenches on an inward side thereof; (b) a sleeve member securely joined to the piston at a first end, and positioned around the central shaft; the sleeve member being passed through the support ring at a second end; the sleeve member being formed with a plurality of spaced concavely curved recesses on the second end thereof; the sleeve member being formed with sloping trenches connected with respective ones of the concavely curved recesses; an angle between the sloping trenches of the sleeve member and an axis of the sleeve member being smaller than an angle between the sloping trenches of the support ring and an axis of the support ring; and (c) a plurality of steel beads held in respective ones of spaces defined by the sloping trenches, and the concavely curved recesses; when the piston and the sleeve member together are moved rightwards by means of high pressure air supplied by the air pressure power source, the steel beads being capable of relocating from the concavely curved recesses to the sloping trenches of the second end of the sleeve member, and next moving rightwards while being rolled along the sloping trenches of the support ring, thus pushing the central shaft rightwards with multiplied pushing force, and making the tool disk move to the right position, in which it is engaged and secured with the clutch.