Fig. 3114.
Referring therefore to [Figs. 3113] and [3114], suppose the carriage to have completed a feed or cutting traverse, and the operator pushes with his knee the lever or handle h, [Fig. 3114], which revolves shaft m, on which is an arm that moves the belt-shifting rod n, thus moving the belt from fast pulley f to loose pulley f′, thus throwing the feed gear out of engagement and causing the carriage to stop. He then presses down the foot lever l, [Fig. 3113], which operates the belt-shifting rod p, [Fig. 3114], and moves the belt from loose pulley k′, to fast pulley k, which having a crossed belt, operates the pulley f in the reverse direction and traverses the carriage backwards, or on the return motion.
Upon releasing the foot from the lever l, the weight w operates the foot lever l, and the belt is re-shifted from fast pulley k to loose pulley k′, and the carriage stops.
The carriage is formed of iron plates with an open space of about 1⁄2 inch between them, as shown in [Fig. 3114], this space forming a race to permit the carriage to travel past the saw. The only connection between the two sections or parts of the table, is a wide plate at the rear end which secures them together, and causes the lighter portion of the table, which is merely driven by the friction of the rollers c, to always travel with the lower or under portion, which is driven by the rack j. In larger machines for the heaviest work, both sections are driven by a rack motion.
The guide motion for the carriage is constructed as follows:
a, a, are brackets placed at intervals along the whole frame work.
These brackets support rollers c, which have flanges on them to prevent any side motion of the carriage, the construction being most clearly seen in [Fig. 3113]; b being a bearing for the shaft v of the rollers. Each section of the carriage, it will be seen, has two ribs or ways which rest on the rollers, which are arranged four on each shaft v (i.e. two for each section of the carriage).
The fence or gauge against which the face of the work runs is very simply arranged as is shown in [Figs. 3113], and [3114], being secured to the shaft q, by a long bolt t, threaded into the top of the fence, and at its lower end abutting against a shoe fitting partly around the top of the shaft q. It is squared at the top to receive a wrench or handle u, and it is obvious that unscrewing the handle releases the fence from shaft q, so that the fence may be moved rapidly by hand across the table to approximate the adjustment of the fence from the saw. The fence having been thus approximately adjusted, and locked to the shaft by means of the handle u, the final adjustment is made by means of the hexagon nut w, on the bed of the shaft nut x, serving as a lock nut, to hold q in its adjusted position.