Bookbinding and the Conservation of Books
A Dictionary of Descriptive Terminology

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ruling machines

The machines used to rule lines on paper according to a predetermined scheme. There are two basic types of ruling machines in use today: the pen ruling machine and the disc ruling machine. The pen ruler applies ink in lines by means of multiple pens. It is the most common type of ruling machine in general use, and is also the one usually regarded as producing the best results. It is used for short-run general ruling and is capable of producing lines in the most intricate patterns. Its operation is relatively simple. The paper is fed from the feed board onto an endless moving blanket, each sheet being kept in position on the blanket by means of thin cords stretched around a series of plain and grooved rollers. The pens are held in a slide fitted on the carriage and positioned according to the pattern to be ruled. The pens rest lightly on the paper and rule the lines as the sheet passes beneath. After passing under the pens, the sheet is carried on cords underneath the machine a nd onto another blanket to permit the ink to dry before delivery to the pile at the end of the machine. The pens on the carriage are arranged to rule along the length of the sheet forRUN-THROUGH RULING . For "struck work" the carriage may be lowered or raised at any required position on the sheet. It is automatically operated by a system of cam wheels at the side of the machine that are synchronized with a gate in front of the feed board which retains and releases each sheet in such a manner that it passes under the pens at the proper time. The pens may be set in a slide in a straight line so that they drop and lift in a straight line, or they may be staggered so that they drop and lift in different alignments, e.g., for box headings. Different colors of ink may be ruled at the same time from the same set of pens on the same carriage provided they are not too close together. Pen ruler s are designed with one or more carriages, which permits additional sets of pens to be used on the same sheet if required by the pattern, or separate carriages may be used for different colors of ink.

The disc ruler transfers the ink to the sheet by means of thin revolving discs instead of pens. Its principal advantage over the pen ruler is that, on two-sided machines, both sides of the sheet can be ruled in one operation; in addition, some disc machines will rule, count, perforate, slit, and jog the sheets, all in one operation. Despite these advantages, however, they are still considered to be less versatile than pen rulers in the combinations of intricate patterns they can rule. In addition, disc rulers have a tendency to produce broken lines. On one-sided disc rulers, the discs are arranged on spindles according to the pattern of ruling required. The spindles are set around a cylinder over which the paper is conveyed by means of thin cords. On "striker" machines the spindles are arranged so that they can drop and lift the discs as required by the ruling pattern; however, since each row of discs is set on one spindle, and therefore in one line, a separate spindle has to be used for each "step" (and also for each color on most machines), whether or not the lines run off one end of the sheet. Two-sided (perfecting) machines have an additional cylinder and after the sheet has been ruled on one side it is carried by the cords to the second cylinder to be ruled on the reverse side before being conveyed to the delivery pile. (190 , 320 )

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