GB375247A - Improvements in or relating to gear cutting machines - Google Patents

Abstract

375,247. Gear-cutting. GLEASON WORKS, 1000, University Avenue, Rochester, New York, U.S.A.-(Assignees of Hill, M. H. ; 1000, University Avenue, Rochester, New York, U.S.A.) March 9, 1932, No. 7090. Convention date, March 14, 1931. [Class 83 (iii).] Attachments for shaping ; tools.-A gearcutting machine is provided with means, which may be embodied in an attachment for use on existing machines, for automatically chamfering the teeth as they are cut. In an application to a machine for roughing out curved bevel gear teeth, by means of a rotary annular face mill 24, the cutting mechanism is housed in a column 21 and the cutter is fed towards the work G mounted on a spindle in a head 22, and, on completion of a tooth, is withdrawn while the work is indexed. The indexing mechanism is operated from a cam 33 driven in timed relation with the feed mechanism and arranged to reciprocate a curved rail 35 connected by gearing (not shown) with the notched indexing plate 32. The cam 33 is timed so that the rail is oscillated to effect indexing while the cutter is clear of the blank. A support 40 is secured to the head 22 and is fitted with a reciprocatory slide 44 carrying an adjustable head 48 having a pivot pin 53 which carries a tool block 52 in which the tool 55 is secured by a screw 56. The tool, Fig. 8, is of trapezoidal section and presents a cutting edge 58, a portion 57 being milled away to clear the bottoms of the blank tooth spaces. An arm 60 on the tool block is held against an adjustable stud 62 by a spring 63 so that as the slide 44 reciprocates the tool swings about the point of engagement of the arm 60 with the stud 62 to give a swinging motion to the chamfering tool. The tool slide is withdrawn and is normally held in inoperative position against an abutment 105 by a spring 70. The slide is actuated by a connecting-rod 77 pivoted on a crank 80 mounted on a shaft 82 whose lower end is fitted with an arm 84 provided with a flatted pin 86. The rail 35 carries blocks 89, 91 the latter being provided with a cam block 95 coacting with the pin 86. When the rail 35 is moved to the left, Fig. 4, a bevelled surface on the cam engages the rounded side of the pin and the cam is depressed so that it can pass under the pin without actuating the arm 84. During this movement of the rail the indexing mechanism is actuated thus bringing a tooth which has just been cut into alignment with the chamfering tool. When the rail is reversed the flatted surface of the pin coacts with the cam 95 and the crank member 80 is thus actuated to operate the chamfering slide. After the pin has cleared the cam, the tool is returned by the spring 70. The cutter 24 is then again fed to cut a fresh tooth space in the block, the rail 35 being stationary during the feed of the cutter. The chamfering slide may be manually operated for setting up by means of a handle 109. The chamfering cut serves to remove the sharp tooth corners as shown at C, Fig. 12.