U.S. Supreme Court
Lovell Manufacturing Co. v. Cary, 147 U.S. 623 (1893)
Lovell Manufacturing Company v. Cary
Argued January l7-18, 1893
Decided March 6, 1893
147 U.S. 623
Letters patent No. 116,266, granted to Alauson Gary, as inventor, June 27, 1871, for an improvement in modes of tempering springs, are invalid, in view of the state of the art, for want of patentable invention.
The invention appears from the specification to be a method of restoring steel wire which has been mechanically strained by subjecting it to a temperature of 600°, more or less, and the claim limits the method to its application to "furniture or other coiled springs," but the process, as applied to those springs, was not different, in method or effect, from the same process when applied to any mechanically strained wire or to steel made in straight pieces or strips or otherwise.
The invention was anticipated by the prior use of New England wire clock bells and of blued hair springs, used in marine clocks. The treatment to which those articles were subjected was in all respects the same in the prior use as in the patented process.
It does not amount to invention to discover that an old process is better in its results, when applied to a new working, than would have been expected, the difference between its prior working and the new working being only one of degree, and not one of kind.
There was nothing more than mechanical skill in arriving at the alleged invention, in view of the state of the art.
The point considered that no one had used the former processes for the manufacture of furniture springs, and that as soon as Cory's process was made known, the art of making furniture springs was revolutionized.
The cases in this Court on the subject of double use considered as to whether it is a patentable invention to apply old and well known devices and processes to new uses in other and analogous arts. chanroblesvirtualawlibrary
The case is stated in the opinion.