Patent ID: 6220116
Filing Date: 2001-04-24
Classification: B23Q,Y10T

Abstract:
A rotary indexing table, comprising:a stationary base having a first stationary gear assembly mounted thereon, and having a central longitudinal axis;a rotary drive means having an axis of rotation which is coincident with said central longitudinal axis;a first crank arm mounted on said rotary drive means for rotational movement therewith;a second planetary gear assembly rotatably mounted on said first crank arm so as to be driven thereby around the periphery of said first stationary gear assembly;each of said first stationary gear assembly and said second planetary gear assembly having complimentary gear teeth for meshing relationship with one another;a second crank arm mounted on said second planetary gear assembly for rotational movement therewith;a freely rotatable drive stub mounted on said second crank arm; anda rotatable table mounted for rotation about an axis of rotation which is coincident with said central longitudinal axis, said rotatable table including a radially directed force receiving member at one side thereof;wherein said freely rotatable drive stub is coupled to said radially directed force receiving member in force transmitting relationship therewith, whereby driving force is transmitted from said freely rotatable drive stub to said force receiving member so as to cause rotational movement of said rotatable table;where said drive stub is coupled to said radially directed force receiving member so as to be freely moveable along said force receiving member as driving force is transmitted from said drive stub to said force receiving member during rotational movement of said rotatable table whereby, whenever drive force is being transmitted to said force receiving member, the direction of force transmission is perpendicular to said force receiving member;wherein one of said first stationary gear assembly and said second planetary gear assembly comprises a pair of identical gears, and the other of said first stationary gear assembly and said second planetary gear assembly comprises a single gear;wherein one of said pair of identical gears is rotated and secured in place with respect to the other of said pair of identical gears in such a manner that the gear teeth on said one of said pair of identical gears are offset with respect to the gear teeth on the other of said pair of identical gears; andwherein the gear teeth on said one of said pair of identical gears contact one side of the gear teeth on said single gear at the point of contact between said pair of identical gears and said single gear, and the gear teeth of the other of said pair of identical gears contact the other side of the gear teeth on said single gear at said point of contact therebetween.