Patent Circular Saw without a Shaft

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The annexed engraving is a perspective view of the invention of Ammi M. George, of Nashua, . ., for running a circular saw without an arbor, and respecting which so many paragraphs have appeared in different papers in our country. A patent was granted for the invention on the 11th of last month (Jan. 1S53.) We believe we shall be able to explain the invention in a very few words. A is the log carriage ; is the frame, and there is a log on the carnage ; L is a saw without a shaft or spindle ; it is of the form of a ring, and its inner edge is guided in the grooves of two friction metal rollers inside. This saw is driven by friction pulleys. Ill I, two on each side, one above and the other below, they run on the face of the ring saw, and drive it round. The saw is of such a diameter as to allow the log to pass through inside of the pulleys. The driving friction pulleys are driven from the main shaft of a water wheel, by belts, D D, which rotate the shafts, C C, on opposite sides, one above and the other below. Belts, F F, from the secondary driving pulleys, , drive the pulleys, G G, and the shafts of their respective friction pulleys, I I. The whole parts of this machine will, by this description, be rendered plain to any person in the least acquainted with machinery. The object of the invention is to saw boards of a diameter nearly equal to that of a circular saw ; the driving friction pulleys are -.* .crefore very narrow, so as to allow of as much space as possible between them. The inventor intends also to save something in the price of saws by having merely ring plates made, with steel teeth inserted in the edges. More information about the sale of rights, &c. may be obtained of the inventor at Nashua, N. H., or John Mullay, of Bangor, Me., who is an assignee of one-half of the patent.

Scientific American Magazine Vol 8 Issue 24This article was published with the title “Patent Circular Saw without a Shaft” in Scientific American Magazine Vol. 8 No. 24 (), p. 185
doi:10.1038/scientificamerican02261853-185b

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