Planing Machine, a machine for planing lumber by mechanical power. One of the earliest forms, invented by Gen. Bentham of England in 1791, drove a slightly modified hand plane. A machine patented by Mr. Bramah in 1802 performed its operation by the rotation of a vertical spindle, carrying at its lower extremity a horizontal wheel, the rim of which was furnished with 28 cutters or gouges, which were followed by a plane also attached to the wheel. Thus the rough surface of the board was trimmed and left perfectly smooth as it was carried by suitable mechanism from end to end. American patents were occasionally granted for planing machines from the year 1800 to 1828, when William Wood-worth of New York patented the celebrated Woodworth planing machine. This performs its operation by the use of cylindrical cutters, or cutters attached to a horizontal shaft revolving with great velocity while the board is borne along under and in contect with them by means of two or more horizontal rollers, which clamp the board on either side, the rollers being driven by mechanism communicating motion from the cylinder.

Though the cylindrical machine was not originally invented by Woodworth, his claims covered such essential improvements in some of its details as to render the patented modifications invaluable, and thus gave him an almost exclusive monopoly. In 1829 Uri Emmons obtained two patents, one for cylindrical and one for circular planing machines. In 1836 Thomas E. Daniels of Worcester, Mass., greatly improved the Bramah or circular machine. The Daniels planer is usually constructed with but two cutters, and the plane of the Bramah machine is entirely dispensed with. It is still preferred for cabinet and other fine work. Many attempts were made to supersede the Woodworth machine by the use of stationary cutters, but for ordinary practical purposes the former are preferred. The patent right of the Woodworth machine was sustained by the courts during a term of 28 years, under the original patent of 14 years and two renewals of 7 years each. Numerous improvements are annually added to these machines, descriptions of which may be found in the patent office reports.