Patent GB-190905172-A (GB)
Title: Improvements in Universal Dividing Heads for Machine Tools.
IPC: B23Q16/02
Filed: 1909-03-03
Granted: 1909-11-11
Abstract: 5172. Loewe & Co., L.. and Barth, C. March 3. Attachments for milling.-In a universal dividing- head for machines for milling spiral grooves or toothed wheels &c., the feeding and dividing attachments, which have an independent drive for enabling them to be applied to existing machines, are both contained in the casing of the universal dividing head. The casing 1, which is fixed on the work-table, is fed by a screw 17, which is driven by toothed change-gear from a shaft 13<a> operated by worm gear from the driving-shaft 9. In order to provide for a quick-return motion, the driving- pulley 3 carries two pairs of planet-wheels, of which the pair 4,4<1> engage a bevel-wheel 7 fixed on the shaft 9, and the pair 5, 5<1> engage a bevel-wheel 8, which may be held from rotation to produce the slow-feed motion or clutched to the shaft 9. The bevel-wheel 8 is held from rotation for the slowfeed motion by a ratchet-wheel 12 and a pawl 13, Fig. 5, which is raised out of contact with the wheel by a projection 23, Fig. 4, on a rod 18. operated by a slotted lever 19 and tappet rod. On raising the pawl, a spring 31 moves the clutch 10 to fix the bevel-wheel to the shaft 9 for the quick return, and when the projection 23 moves away from the pawl a spring 24 returns the pawl into engagement with the wheel, the pawl engaging a bevelled surface on the clutch lever 34 to remove the clutch. Towards the end of the quick-return motion, a second stop 25 moves a pawl 26 out of engagement with a second ratchet-wheel against the action of a spring, and the clutch 30 is put in gear by the spring 32 to connect the shaft 9 to the sleeve 35, which, through variable change-gear 36, 37, 38, 39 and worm gear, rotates the dividing-head. After one rotation of the sleeve 35, the pawl is moved by the spring into the notch in the ratchetwheel. The reversing rod is held in position by a spring-pressed bolt 45, Fig. 4. In a machine for producing spiral grooves and toothed wheels, Figs. 9 and 10, the shaft 9 carries a wheel 46, which drives a wheel 48 on a shaft 47 and through a clutch 49 operates wheels 50', 51 when grooving to rotate the wheel 36 of the change-gear for the dividing-head continuously during the forward travel of the work. The table is operated from the sleeve 35<1> to which it is connected by a pin 54 on a spring-pressed sleeve 52 passing into a hole in a disk 56 which has a clutch 57 moved by hand to connect the disk 56 to the wheel 58, which rotates the worm for driving the feed-gear. When the stop 25<1> on the rod 18<1> engages a stud 59, the lever 53 connected to the steeve 52 is moved back against the spring 60 to withdraw the pin 54 from the disk 56, so that for one rotation of the shaft, the dividing-head may be rotated while the feed is stopped. When this machine is to be used for milling toothed wheels &c., the clutch 57 is disconnected and the clutch 49 put in gear with the wheel 50, so that the feed takes place through wheels 46, 48, 50, 58, the disk 56 being held by a pawl. The reversing-rod 18<1> then moves the clutch from the wheel 50 to the wheel 50<1> to rotate the dividing-head with the feed stationary, the pin 54 being at this time out of the hole in the disk. After one rotation of the wheel 51, the pin is reengaged by the spring 60, and the clutch 49 is returned by the lever 53. The collar 62 may be fixed to the clutch by a screw 63, so that it may be loose when cutting spiral grooves.