Patent ID: 8608412
Filing Date: 2013-12-17
Classification: B23B,B23Q,Y10T

Abstract:
1. A boring bar feed mechanism comprising: a rotatable and axially translatable cylindrical boring bar having at least one tool holder located adjacent a working end of the boring bar for supporting at least one bore tool; a rotation mechanism for selectively rotating the boring bar in a rotational direction while allowing axial translation of the boring bar; an axial translation mechanism for axially translating the boring bar, the axial translation mechanism comprising a feed shaft extending parallel to and spaced from the boring bar and having a threaded section located at least adjacent the working end the boring bar and the threaded section extending over at least an axial length of the feed shaft corresponding to an axial range of motion of the boring bar; a feed coupling extending between and generally perpendicular to the feed shaft and the boring bar for axially translating the boring bar due to rotation of the feed shaft, the feed coupling comprising a threaded coupler rotationally and axially fixed into a first end of the feed coupling and engaging with the threaded section so that the feed coupling is driven in an axial direction along the feed shaft by rotation of the feed shaft; the boring bar being rotationally mounted within a coupling bore in a second end of the feed coupler and axially fixed in the coupling bore of the feed coupler so that the boring bar is axially moved by axial movement of the feed coupling upon rotation of the feed shaft; a cam being rotationally fixed to the boring bar for rotating with the boring bar; a cam follower, having an extension, interacting with the cam; a plunger housing being supported by the extension of the cam follower, and the plunger housing accommodating at least one feed plunger; a converter gear being supported by the feed shaft; and the at least one feed plunger interacting with the converter gear to facilitate indexing of the converter gear supported by the feed shaft; wherein the plunger housing is pivotally supported by the extension of the cam follower to permit the plunger housing and the feed plunger to have a limited pivoted motion relative to the cam follower as the cam follower oscillates back and forth and indexes the feed shaft; and the converter gear has a relatively fine gear ratio which permits indexing of two teeth of the converter gear for each oscillation of the cam follower.