US 4,353,271 AGranted

Multiple position rotary index table

AssigneeA.G. Davis Gage and Engineering Co.

InventorDaniel J. Pieczulewski

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Abstract

A precision rotary indexing fixture is disclosed of the type including a top plate adapted to have work pieces mounted thereon with the work plate indexed to any of a plurality of precision rotary positions. The precision locking of the top plate is achieved by serrated coupling rings, one mounted on the outer periphery of the top plate, the other mating ring mounted on a base structure. The top plate is locked in various index positions by the application of disc spring sets acting on the top plate through an annular piston and a set of bearing elements mounted in opposed grooves in the piston and a race ring mounted to the top plate. The fluid forces acting on the piston acts to release the locking pressure exerted by the disc spring sets and release the coupling serration engagement during indexing of the top plate. The annular piston and disc spring sets act on the top plate in a position closely adjacent to the coupling ring radial location to minimize bending deflection of the top plate upon the application of locking forces by the disc spring sets. The use of a disc spring set to carry out locking of the top plate provides a fail-safe feature to lock the top plate in the event of a power failure or other malfunction causing loss of hydraulic or pneumatic actuating pressure.

Claims15

Dependent claims

A rotary indexing table comprising:

a generally circular top plate;
a fixed base structure;
means mounting said top plate for rotation about an axis on said fixed base structure and limited axial movement relative said base;
indexing-locating means for positively locating said table top plate in any of a plurality of rotated positions about said axis of rotation;
means for selectively releasing said top plate from said indexing-locating means to enable rotation of said top plate to respective indexed positions rotated about said axis of rotation;
said indexing-locating means including a skirt portion formed on said top plate extending axially about the periphery of said top plate, said skirt portion being formed with a series of serrations extending radially along the axially most remote surface of said skirt portion;
further including a corresponding rim portion formed on said fixed base structure and being formed with corresponding serrations to said top plate serrations extending radially outward and in opposition to said top plate serrations, said top plate and fixed base structure serrations being engagable with each other in each of said plurality of indexed positions upon axial movement of said top plate into engagement toward said base structure;
said indexing-locating means further including means applying a locking force acting between said top plate and said fixed base structure forcing said serrations into engagement thereof;
and
said indexing-locating means also including a piston having an outside diameter slidably mounted in a bore formed in said fixed base structure, bearing means acting between said outside diameter of said piston and said top plate, said bearing means including an outer raceway carried by said top plate, said bearing means having means absorbing radial and axial loads to establish an axial driving connection between said piston and said top plate causing said piston and said top plate to move together axially while allowing relative rotation therebetween, means for exerting locking and releasing forces on said piston, whereby said piston exerts a locking and releasing force on said top plate through said bearing means.

7 more elements

A rotary index table comprising:

a generally circular top plate;
a fixed base structure;
and
means for supporting said top plate for rotation about an axis;
indexing-locating means selectively operable to positively locate said top plate with respect to fixed base structure in each of a plurality of rotary positions of said top plate about said axis, said means including means for relatively moving said top plate and said fixed base structure axially, and further including coupling serrations extending peripherally about said top plate and said fixed base structure and movable into and out of engagement upon said relative axial movement therebetween;
means for imposing a releasing force and an engaging force on said top plate tending to move said top plate to said disengaged position, said means including fluid pressure actuator means tending to produce said relative movement to said disengaged position, including a piston slidably mounted in said fixed base structure for movement along said axis of rotation of said top plate and means for drivingly connecting said top plate and said piston for axial movement together, including rotary bearing means supporting said top plate on said piston, and also including means for applying a fluid pressure to said piston tending to move said piston and top plate to cause separation of said coupling serrations;
and
spring bias means urging said rotary index table to said locked position whereby upon successation of the application of fluid pressure through said fluid pressure actuator means, said top plate is positively located with respect to said fixed base structure with said spring bias engagement force acting thereon, said spring bias means including a plurality of anchoring plugs disposed about said axis of rotation of said top plate and extending in an axial direction, said anchoring plugs fixed to said fixed base structure and extending into said piston, said spring means also including springs acting between each of said anchoring plugs and said piston to produce said engagement force acting on said piston.

5 more elements

Dependencies are inferred from the claim text.