Fig. 1883.
The construction of the bearings for the cutter driving spindle of the machine is as in [Figs. 1882] and [1883]. a is the spindle having a double cone to fit corresponding cones in the sleeve b, the fit of one to the other being adjusted by means of the nut c, which is threaded upon a. The mouth of a is coned to receive the arbors or mandrels for driving the mills or cutters. At the back bearing, [Fig. 1883], the journal a′, and bore of the sleeve b′, is parallel, this sleeve being split at the top so that when it is (by means of nut d) drawn within the head e its coned exterior will cause it to close to a proper fit upon a′, by which means the wear of the parts may be taken up as they become perceptible.
Fig. 1884.
Fig. 1885.
The head j, [Fig. 1880], is used (in connection with the foot block i) to suspend or hold work by or between centres, its centre fitting into the spindle at h, which is capable of being revolved continuously (to enable the cutting of spirals), by means of change gears, and intermittently through a given part of a circle by means of the index wheel i. The block j carrying the spindle is also capable of elevation for conical or taper work, two examples of such uses being shown in [Figs. 1884] and [1885], in which c is the cutter and w the work.