602,494. Making commutators. WILLIAMS, W. P. (Dayton Precision Manufacturing Co.). Aug. 23, 1945, No. 21655. '[Class 83 (ii)] A commutator assembling machine comprises a removable ring-shaped retaining element within which commutator segments are assembled, poweroperated means for inserting segments into the retaining element and power-operated clamping means for tightly gripping a completed assembly of segments, the inserting and clamping means being operated in timed relation. The machine comprises a frame 1, a drum 3 carrying dogs for operating valve rods projecting from a valve chest 2, which through a hydraulic system controls the operation of the various parts of the machine. A supply of mica pieces for insulation between the commutator segments is placed in a shoot 5 from which they are fed by gravity on to a reciprocating slide by which they are transferred with the segments into a receiving tool or holder. The slide 38 carries an operating portion 45, which may be readily changed to accommodate different sizes of segments, and is connected by a block 39 to a rod 40 having at one end a portion 41 of reduced diameter projecting into a cylinder connected to a supply of hydraulic fluid at constant pressure. The other end of the rod 40 works in a cylinder 44 connected to the fluid supply intermittently when it is desired to move the slide to the left, as shown in Fig. 1, the pressure on the larger end of the rod then overcoming the constant pressure on the smaller end. When the cylinder 44 is connected to exhaust, the slide is returned to the right-hand position and thrusts a segment and mica piece into the grip of two rubber-faced heads 6, 6a, which are indexed step-by-step. The heads are mounted on shafts 49 and 50, Fig. 5, keyed to sleeves 59, Fig. 8, which are rotated from a shaft 61 through gears 60, 62 and 63. Channelled rings 65 at the outer ends of shafts 49 and 50 are engaged by lugs operated by piston-rods 67 to move the heads into and out of operative position. Shaft 61 is intermittently rotated by means of a ratchet, the driving pawl of which is reciprocated by a hydraulicallyoperated rod or piston similar to that used for operating the slide 38. The segments held between the heads 6 and 6a are supported circumferentially by a resilient gapped ring 31 which is thicker at the middle and tapers towards the ends and is housed in a circular opening or jaw in a member 29, Fig. 7. A thrust rod 30 passes through a bore in member 29 and bears on the ring 31 and by pressing on the rod, the ring may be forced outwardly in the jaw, thus constricting the ring about the segments due.to the shape of the parts. Member 29 forms part of a receiving tool 7, Figs. 1 and 7, and is supported and positioned on a standard 17 by means of a stepped lip 32 projecting beneath an abutment plate 18. At the other end the tool is supported on a standard 10 by means of a pin 33 depending into a longitudinal slot. A bell-crank lever 21 pivoted to a horizontal projection 19a, Fig. 6, at one end of the tool extends along the rear end and also along one side face of the tool 7 where it is adapted to engage a stepped latch 23. By supplying hydraulic fluid to a cylinder 36, a bell-crank 16 is operated to press the lever 21 laterally inwards. This causes an adjustable screw 21a carried by the lever to bear on a thrust-rod 20 which, in turn, bears on the rod 30 so as to cause the ring 31 to be clamped around the assembled segments, the latch 23 serving to retain the parts in this clamping position. The tool, together with the assembled segments can then be removed to a press for inserting a sleeve and collars and for upsetting them to complete the assembly ready for machining. When the first segment is thrust by the slide 38 between the heads 6 and 6a it is supported by a small platform 54, Fig. 5, carried by a projection 53 extending from a finger 51 sliding in a slot in the head 6a. When the assembly is finished and just before the actuation of the clamping mechanism, a piston 55 is advanced to move the finger 51 so that the platform is withdrawn to a position substantially on the axis of the assembly. Specification 596,133 is referred to.