Tesla Polyphase Patents - Westinghouse vs. Thomson-Houston Electric Co.

Two suits have just been instituted against the ThomsonHouston Company by the Westinghouse Electric and Manufacturing Company and the Tesla Electric Company. These suits are based upon four patents of Nikola Tesla relating to the system of transmitting electric power by "multiphase" alternating electric currents. The patents said to be infringed were issued May 1st, 1888, and are numbered respectively 381,968, 381,969, 382,280 and 382,281. We give below the claims of the two latter patents which are the method patents, the two former claiming the apparatus.

The claim of patent No. 382,280 is: "The method herein described of electrically transmitting power, which consists in producing a continuously progressive shifting of the polarities of either or both elements (the armature or field magnet or magnets) of a motor by developing alternating currents in independent circuits, including the magnetizing coils of either or both elements, as herein set forth."

The claim of patent No. 382,281 is: "The method herein described of transmitting power by electromagnetic motors, which consists in continuously and progressively shifting the poles of one element of the motor by alternating currents and magnetizing the other element by a direct or continuous current, as set forth."

The suit has been brought in the U. S. Circuit Court at Hartford, and a specific infringement is in the plant for transmitting power from Farmington to Hartford.