Linotype mechanism

by Alvin Garfield Swank; Raymond Means

The two justification levers are located under the metal pot and main cams, extend forward from the back of the machine, and connect with the vise justification rods. These levers operate the justification rods and bar, assembled on the vise, and the vise closing lever. The levers get their motion from rollers which follow the contour of cams No. 4 and 5, and are held against the cams by two strong springs in the rear of the machine. The justification bar rests on top of two rods that are forced up and down by the justification levers in guides in the frame of the vise. The rods are connected together by the justification bar and a diagonal brace rod, the various parts being connected by wing pins. The function of the justification bar is to drive the spacebands upward to justify the line just before the line is cast.

The right-hand lever is called the first justification lever and is operated by cam No. 5. There are two upward movements of this lever: The preliminary, which justifies the line lightly; and the final, which justifies the line tightly for the cast.

When the justification lever forces the rods upward for the first justification, the rod block moves upward at a slight angle, striking the spaceband at the right-hand end of the line first, and the others in quick succession. This action is so rapid that all the spacebands appear to move upward simultaneously. This causes the line to spread from right to left. After the first justification the spacebands stand at an uneven height, those at the right of the line being a trifle higher than those at the left. Since the line of matrices must fill the entire space between the jaws in order to cast, it is apparent that in order to get the greatest possible freedom of action it is necessary that the matrices be pushed toward the left gradually. Should the rod block come up perfectly horizontal, the spacebands would move to the left at the same time they are moving upward. This would cause them to drag on the rod block and prevent a good lockup and alignment and a possibility of bending the spacebands. By coming up on a slight angle, each band is practically justified separately in its particular part of the line, and the dragging of the bands on the rod block is greatly reduced.

The justification lever also makes a slight upward movement after the slug has been ejected. This movement operates the slug lever, through a roller, and pushes the slugs forward in the stick.

The spring which operates the first justification lever should be strong enough to justify the line properly, regardless of the number of spacebands in the line. Before changing the tension at any time, be sure that the mold slide is properly adjusted. If the mold should lock too tight against the line it would bind the matrices and prevent proper justification. This would give the appearance of weak justification springs.

The left-hand lever is called the vise closing lever, and is U-shaped on the forward end. One arm is connected by a hinge pin to the left-hand vise closing wedge and block. The other arm grooves around the left-hand justification rod, beneath a lug on the rod.

After the line is brought to the casting position, the vise closing lever moves upward, immediately followed by the justification lever. The vise closing lever locks the left-hand vise jaw against the line and assists the justification lever on its second movement upward. While these two levers move almost in unison, their functions are different. On second justification, the vise closing lever moves upward slightly in advance of the first justification lever and supports the left-hand end of the spaceband driving block, so that the spacebands are all driven to an equal height. On the first justification, the vise closing lever does not come in contact with the spaceband driving block.

The justification spring is stronger than the vise closing spring. If for any reason the justification springs are removed, care should be taken that they are not changed while replacing them.

THE VISE

The vise is that part of the machine which carries, as its main parts, the first elevator slide, the vise justification rods, the trimming knives, the vise automatic, the vise jaws, the slug lever, the mold disk locking stud blocks, the mold banking blocks, and the knife wiper.