Duff v. Sterling Pump Co. - 107 U.S. 636 (1883)
U.S. Supreme Court
Duff v. Sterling Pump Co., 107 U.S. 636 (1883)
Duff v. Sterling Pump Company
Decided April 2, 1883
107 U.S. 636
1. Reissued letters patent No. 6873, granted to Mrs. P. Duff, E. A. Kitzmiller, and R. P. Duff, Oct. 6, 1875, for an "improvement in washboards," on the surrender of original letters patent No. 111,585, granted to Westly Todd, as inventor, Feb. 7, 1871, are not infringed by a washboard constructed in accordance with the description contained in letters patent No. 171,568, granted to Aaron J. Hull Dec. 28, 1875.
2. In view of prior inventions, the claims of the letters patent granted to Todd must be limited to the form which he shows and describes -- namely, projections bounded by crossing horizontal and vertical grooves. They do not cover diamond-shaped projections bounded by crossing diagonal grooves.
3. In the field of washboards made of sheet metal, with the surface broken into protuberances formed of the body of the metal so as to make a rasping surface, and to strengthen the metal by its shape, and to provide channels for the water to run off, Todd was not a pioneer. He merely devised a new form to accomplish those results, and his letters patent do not cover a form which is a substantial departure from it.
The case is stated in the opinion of the Court.