Pneumatic drills were developed in response to the needs of mining, quarrying, excavating, and tunneling. The first "percussion drill" was made in 1848 and patented in 1849 by Jonathan J. Couch of Philadelphia, Pennsylvania. In this drill, the drill bit passed through the piston of a steam engine. The piston snagged the drill bit and hurled it against the rock face. It was an experimental model. In 1849, Couch's assistant, Joseph W. Fowle, filed a caveat for a percussion drill of his own design. In Fowle’s drill, the drill bit was connected directly to the piston in the steam cylinder; specifically, the drill bit was connected to the piston’s crosshead. The drill also had a mechanism for turning the drill bit around its axis between strokes and for advancing the drill as the hole deepened. By 1850 or 1851, Fowle was using compressed air to drive his drill, making it the first true pneumatic drill.
The demand for pneumatic drills was driven especially by miners and tunnelers because steam engines required fires in order to operate and the ventilation in mines and tunnels was inadequate to vent the fires' fumes; there was also no way to convey steam over long distances (e.g., from the surface to the bottom of a mine); furthermore, mines and tunnels occasionally contained flammable explosive gases such as methane. By contrast, compressed air could be conveyed over long distances without loss of its energy, and after the compressed air had been used to power equipment, it could still serve to ventilate a mine or tunnel.
In Europe since the late 1840s, the king of Sardinia, Carlo Alberto, had been contemplating the excavation of a 12-kilometer (7.5 mi) tunnel through Mount Fréjus in order to create a rail link between Italy and France, which would cross his realm. The need for a mechanical rock drill was obvious and this sparked research on pneumatic rock drills in Europe. A Frenchman, Cavé, designed, and in 1851 patented, a rock drill that used compressed air; however, the air had to be admitted manually to the cylinder during each stroke, so it was not successful. In 1854, in England, Thomas Bartlett made and then patented (1855) a rock drill in which the drill bit was connected directly to the piston of a steam engine. In 1855 Bartlett demonstrated his drill, powered by compressed air, to officials of the Mt. Fréjus tunnel project. (In 1855, a German, Schumann, invented a similar pneumatic rock drill in Freiburg, Germany.) Bartlett’s drill was refined by the Savoy-born engineer Germain Sommeiller (1815-1871) and his colleagues, Grandis and Grattoni, by 1861. Thereafter, many inventors refined the pneumatic drill.
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