Divisible Flanged Shaft Collar: Two Halves Locked by Lugs, Bolted Through the Shaft in One of Three Hole Pairs (Obey, 1916)

"These shaft collars frequently become broken and it is one of the important purposes of my invention to provide a shaft-collar which can be quickly and easily installed on the shaft without the removal of the shaft from its bearings."

Grip 75 mm round bar in the 3-jaw chuck. Face it and turn the flange to 70 mm. Turn the hub to 32 mm for 40 mm, leaving the flange 10 mm thick. Centre-drill, drill through 15 mm and ream 16 mm. Part off at 50 mm and face the flange's outer face.

Blue the flange and hub. Scribe the split line across the flange through the centre and along both sides of the hub. Mark two chord holes across the split line, 28 mm each side of the centre, in the middle of the flange's thickness; drill them 5 mm right through the flange, square to the split line. Mark three pairs of openings round the hub, at 18, 30 and 42 mm from the flange's outer face and at 90, 30 and 150 degrees from the split line. Centre-punch, and with the collar in the V-block drill each pair 6.5 mm straight through the hub and the bore.

In soft jaws, saw down the split line through flange and hub with a fine hacksaw blade, through the middle of the chord holes. File the cut faces flat. Tap a 5 mm steel dowel pin 20 mm long into each chord hole of one half, leaving 9 mm sticking out: these are the lugs, and the other half's holes are the slots. Put the halves together: they must close with only the saw cut between them, and slide apart only straight.

Mark where the collar's flange must stand and drill a 6.5 mm hole straight across the shaft, 18 mm from that mark, with the shaft in the V-block. Put the two halves round the shaft from the sides, the lugs into the slots, and turn the collar until the 18 mm pair lines up with the hole. Push an M6 x 50 bolt through and tighten a nyloc nut on it. To move the collar, take the bolt out, slide and turn the collar until another pair lines up, and bolt it again.

**James F. Obey** of Centerville, Appanoose County, Iowa, US 1,201,863, dated 17 October 1916, filed 3 August 1915. He claimed a shaft with a transverse hole, "a collar mounted thereon consisting of a longitudinally halved cylinder with an annular flange at one end, one half of the flange being provided with lugs, the other half being provided with corresponding slots", pairs of aligned openings at different points along and round the cylinder, and a bolt through the shaft's hole and a chosen pair. His lugs are bent pieces on the face of the flange that hook into yokes on the other half; ours are pins in holes through the flange, which do the same job. His bolt has a round head; ours is a hex bolt with a nyloc nut. The patent gives no sizes or material; every size here is ours.