Patent ID: 7121776

Claim:
A retrofit apparatus for measuring the vertical displacement of a quill on a milling machine having: a main scale slidably mounted to an indicator, said indicator being capable of displaying the vertical displacement of the quill of the milling machine; a mounting cover having a generally rectangular configuration and an aperture located therein for receiving said indicator; a stop bar fixedly secured to said scale by an attachment means; said quill having a quill shaft attached thereto; said quill shaft being matingly engaged to said stop bar by a quill mount; and wherein the quill shaft moves vertically responsive to a force placed thereon, thereby causing said scale to slide up and down along the indicator; a stop nut assembly for a threaded rod, comprising: a nut body having a face and an axial bore therethrough adapted to receive a threaded rod, said nut body being provided with a transverse bore terminating in a bore end within said nut body; biasing means positioned in the bore end; a plunger positioned in said bore against said biasing means, said plunger being provided with a rod receiving aperture, said aperture being threaded on one side only; a set screw positioned in said face parallel to said axial bore; said plunger having a conical recess adapted to engage said set screw; whereby tightening of said set screw will force said threaded portion of said aperture tightly against said threaded rod, and prevent movement thereof.