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Fig. 2078.

The wheel to be cut is carried as follows: Upon the bed-plate of the machine is placed a head b, [Fig. 2078], corresponding to the headstock of a lathe, opposite which is a head b′, answering to the tailstock of a lathe. These two carry a mandrel d, to which is fastened a face-plate d′ against which the work is chucked. At the end of d′′ is fixed, in the usual manner, the worm-wheel for the dividing mechanism. The cutting arbor is held in a head that is carried in a cross slide c2, [Fig. 2077], this cross slide being a carriage that may be fed along the side extension of the bed, which is broken off in the plan view of the machine, [Fig. 2078]. The two slides thus provided in this machine form in effect a longitudinal and cross feed, answering to the feeds of a lathe carriage and tool rest.

The cutter head m, [Fig. 2077], is composed of two parts, c and m. Provision is made to swing the head in two directions, one of which is noted by the plain arrow and the other by the feathered arrow in the engravings. Between the two the cutter arbor, it will be perceived, may be set at an angle in whatever direction the nature of the work may require. Referring to [Figs. 2076] and [2077], it will be seen that the cutter-driver mechanism operates as follows: The tight pulley a1, driven in the direction noted by the arrow, turns the cone a6 which drives the pulley b. The belt from b passes over grooved idlers, b1, b2, b3, &c., to the grooved pulley b8, which is fast on its shaft and drives a train of gearing that operates the cutter arbor, the train being best shown in [Fig. 2077]. The train of gearing thus driven is composed of gears c1, c2 and c5, the latter being on the cutter arbor. The object of this arrangement is to obtain a high belt velocity. It will be seen that all these gears have their teeth at an angle to their axes, a feature that has been introduced to obtain smoothness of action. To maintain equal tension of belt at whatever angle the cutter may be set, the idle pulley b2 acts as a belt tightener, being carried by the rods t and t1.

Fig. 2079.

Referring now to the feed motions, the machine is provided with a quick return for the cutter, the mechanism of which is as follows: The cone pulley a4, [Fig. 2077], is mounted upon a driver shaft d, [Fig. 2079]. Upon this shaft are two loose bevelled pinions d2 d4, between which, and splined to the shaft, is a clutch f. For the feed traverse the clutch f is moved to engage with the pinion d4, while for the quick return it engages with d2. This device corresponds to the old-style quick-return motion used in some of the heavy English planing machines. The clutch f is operated by a rod l′, and drives the bevelled pinions d2 d4 by friction. The hub of the clutch is coned to fit a coned recess in the hubs of the two pinions. A pair of gears, d6 d7, transmit the motion of d5 to the shaft d1, on the end of which is the pinion e1, Motion is conveyed from this pinion to the feed-screw e, [Fig. 2081], by the intermediate gears e2, e3, e4 and e5, and also by the helical pinions e6 and e7, the latter two being also shown in [Fig. 2081].