In [Fig. 3162], the work is shown passing beneath the two upper rollers, and the spring j (which extends the whole length of the pressure bar), is depressed from the weight of the bar. By this construction, the work is pressed to the table at a point as close as possible to the cutters. The pressure bar p cannot drop beyond a certain point, because of its tail piece y′, [Fig. 3160], which rests on the top of the frame at y′′ when the bar p has fallen to its required limit.
The feed pressure bar p is bolted to its circular links, as shown in [Fig. 3162], in which y is a part of the circular link which is bolted to the pressure bar p.
The delivery pressure bar b ([Fig. 3160]) is riveted to and forms part of its links y. It acts through the medium of spiral springs s, which are carried in cases or boxes s′, which overhang the end of the bar b. A set screw s′′ regulates the pressure of the spring, and a screw a ([Fig. 3162]) regulates the height of the pressure bar.
The adjustments of the feed and delivery rollers are made as follows:
The feed pressure is obtained through the medium of weights, shown at w, w′, in [Fig. 3163], upon the bars a, a′, whose ends are pivoted to the lower ends of links m, n, the upper ends of which are pivoted to the side frame of the machine.
Fig. 3163.
Bar a engages or rests at e, on a lug or projection on the link i, which fits in a recess provided in the side of the frame. This link i, extends up and has a bearing to receive the feed roller (f, [Fig. 3160]), whose driving gear is shown at o.
It is obvious therefore, that the amount of pressure on the feed roller f may be varied by moving the weight w along the bar a.