| 摘要 |
935,199. Tapping. NATIONAL MACHINERY CO. June 8, 1961 [Feb. 24, 1961], No. 20838/61. Class 83 (3). A nut-tapping machine comprises a pusher 74 against which a nut 81 is pressed while a thread is started therein and a guide 84 to prevent rotation of the nut as the tap 87 is moved rearwardly taking the nut with it. The machine has two shafts 14 rotated by a common belt drive 18 with a hand wheel 19 for setting-up purposes. Each shaft is connected to a tapping spindle 23 by rollers 28 engaging a groove 29. A gear on one shaft 14 rotates a cam 41 on a shaft 31 via spur and worm gearing, the cam engaging an adjustably-mounted follower 42 to oscillate a lever 49 and so reciprocate the tapping spindle 23. The shaft 31 also carries a cam to reciprocate the other spindle. The cams work against springs 60 which urge each tap towards a nut. Nuts are fed from a sorter to shoots 13. At the lower end of each shoot is a pusher 74 reciprocated by a cam 57 on the shaft 31 operating through links 59, 63, 62, the latter being mounted on a pivot 67 which yields against springs 72 in the event of jamming. The nuts are prevented from rotation by V-grooves 84. The curved shank tap is mounted in guides 94, 96 in blocks 91, 92 on the spindle 23. The blocks are clamped together with one guide 94 displaced to provide clearance for the nuts as the tap is rotated. At the front of the blocks is an eccentric guide 95. The arrangement assures a concentric rotation of the tap in the nuts being threaded. A spring-pressed stop at the end of the guide 94 prevents nuts being thrown off by centrifugal force. |
