Fig. 1681.—Front View.
[Figs. 1681] and [1682] represent a radial drilling machine, in which the radial arm is carried on a head, which fits a vertical slideway provided on the face of the upright column, and may be moved to any required height on this slideway by means of a rack and worm gear, the latter being shown in the front view.
Fig. 1682.
The seat of the arm on this head is cylindrical, the head being pivoted upon it in order that it may permit of its being rotated to hold the drill at an angle. The drill spindle is carried in a head sliding on the radial arm as already stated, and is driven as follows:—
Motion from the shop driving shaft is communicated by belt to the cone pulley shown at the base of the upright column.
The spindle of this cone pulley drives a belt which passes up the column over an idle pulley on the sliding head that carries the radial arm; hence it passes along the front of the radial arm and partly round a pulley on the drill spindle, two idle pulleys holding it in contact with the drill spindle pulley. Hence it passes over a small pulley at the outer end of the radial arm, and returns along that arm through the sliding head, over an idle pulley to the pulley seen at the head of the vertical column, and from this pulley it passes to the pulley that is on the cone spindle shaft at the base of the column. The drill is provided with an automatic feed actuated by the worm shown on the drill spindle.
