GB203341A - Improvements relating to work positioning in boring and milling machines - Google Patents

Abstract

203,341. Lambert, G. P. Aug. 31, 1923. Boring and drilling; milling. - In a vertical-spindle milling or boring machine the work is accurately positioned in relation to the tool spindle by making measurements between an abutment, permanently fixed relatively to the tool-spindle, and abutments fixed relatively to the work. Work-holders; gauging-devices; jigs. - The work 43, Fig. 3, is supported by clamps 52, 56, 57 on a holder 36 which is secured to a horizontal table on the machine having longitudinal and transverse feeds operated by hand. Ribs 38. 39 on the holder carry rules 40, 41 adjustably held by screws 42 either perpendicularly to each other or at some other angle. The rules are adjusted by means of gauge-blocks and plugs 44 inserted into conical holes in the ribs, the front and rear edges of the rules being preferably parallel. The work-table is set by placing gauge-blocks of the requisite thickness between the rules and a cylindrical surface 33 on a bracket 30 secured to the spindle-head, a hole 32 coaxial with the surface 33 being provided to admit ':he. spindle. In a drilling-machine, a guide-bush may be inserted in the hole 32. Bolts 47 carried bv flexible ribs 55 on the holder serve to position the. work. The rules may be integral so as to form a square. In order to ensure equal pressures always being applied to the gauge-blocks friction clutches may be provided between the handles and corresponding traversing-screws of the table. In the modification shown in Figs. 6 and 9, the bracket 30 has two mutually perpendicular measuring surfaces 68, 69, and the hole 32 is surrounded by a coaxial boss 72 which serves for adjusting the bracket. A pointer 70, pivoted to a plate attached to the spindle 71, is made to contact with the boss, and on the spindle being rotated through one revolution indicates whether the hole 32 is roaxial with the spindle. The work 43 and the rules, one of which is shown at 74. in Fig. 9, are clamped directly to the table, a second set of rules 78 serving as a standard of adjustment. In operation, gauge-blocks are placed between the rules and between the inner rules and the bracket 30 and are secured by clamps 85, 86 which enter holes 87 in the bracket. The work is then placed against the ruler 74 with interposed gauge-blocks of a thickness to bring the desired part of the work under the tool-spindle and the rules and work secured to the table and the clamps removed. Should the rules 74 become displaced, they may be set against the rules 78, a pivoted indicator 88 being used for testing any movement. Milling-machines.-The spindle 1, Fig. 1. is mounted in a rack-sleeve 3 carried by a head 2 vertically adjustable by a screw and hand-wheel 5. the driving pulley 12 being slidably keyed to the spindle. The knee 15 carrying the work-table is vertically adjustable by a screw 28 worm driven from a handle 27.