Lovell Manuf Co v. Cary

• Decision Date: 06 March 1893
• Docket Number: No. 110,110
• Citation: 147 U.S. 623,13 S.Ct. 472,37 L.Ed. 307
• Parties: LOVELL MANUF'G CO., Limited, v. CARY et al
• Court: U.S. Supreme Court

147 U.S. 623

13 S.Ct. 472

37 L.Ed. 307

LOVELL MANUF'G CO., Limited,

v CARY et al.

No. 110.

March 6, 1893.

W. Bakewell, Thos. W. Bakewell, and John K. Hallock, for appellant.

W. C. Witter and W. H. Kenyon, for appellees.

Mr. Justice BLATCHFORD delivered the opinion of the court.

This is a suit in equity, brought March 14, 1885, in the circuit court of the United States for the western district of Pennsylvania, by Alanson Cary and Edward A. Moen against the Lovell Manufacturing Company, Limited, an association under the laws of the state of Pennsylvania, to recover for the alleged infringement of letters patent No. 116,266, granted to Alanson Cary June 27, 1871, for an improvement in modes of tempering springs.

The specification of the patent is as follows: 'Be it known that I, Alanson Cary, of city, county, and state of New York, have invented a new and useful improvement in furniture springs, and I do hereby declare that the following is a full, clear, and exact description thereof, which will enable others skilled in the art to make and use the same. This invention relates to spiral springs, usually made in a conical form, of steel wire, and extensively used in upholstering sofas and chairs and for bed bottoms, etc., and consists in subjecting the spring to a tempering process after it has been completed in the usual manner, whereby its strength, elasticity, and durability are greatly increased. The ordinary furniture spring is made of hard-drawn wire, coiled and forced to the proper shape, and when this is done the spring is considered finished, without having been subjected to any tempering process other than what is incidental to the drawing of the wire. To give them a finished appearance, however, copper or other material is frequently applied by suitable means. The metal being greatly condensed and hardened in the process of drawing the wire, a good degree of elasticity is given the wire thereby but in bending or coiling the wire into the proper shape the metal is unavoidably weakened,the outer portion of the wire coil is drawn or stretched, while the inner portion is crushed or shortened. When straight bars or wire is subjected to the bending process, the stretching or drawing of the outer and crushing of the inner portions are inevitable results. This greatly reduces the elasticity, strength, and durability of the spring. Being a manufacturer of furniture springs, and aware of this difficulty, I have tried many experiments with a view of restoring the wire, after being bent or formed into springs, to its normal condition. This, I have discovered, can be done by subjecting the spring to a degree of heat known as 'spring-temper heat,' which is about 600x, more or less, and that a subjection to this temperature for about eight minutes is sufficient to produce the result desired. This temperature I have found to be sufficient to so far relax or produce a complete homogeneity of the metal of the spring as to add from twenty to thirty per cent. to the value of the spring consequent on its increased powers of resistance. Thus treated the spring will bear much heavier pressure, and its strength and elasticity are much less impaired than the ordinary spring after long-continued use. For carrying out and putting in practice my discovery, I have invented a tempering oven, for which I have an application for letters patent now pending.'

The claim is as follows: 'The method of tempering furniture or other coiled springs, substantially as hereinbefore described.'

The answer set up various defenses, and among them want of novelty and noninfringement. It averred that the process set forth in the specification of the patent was merely a method of increasing the elasticity of steel, applicable not only to furniture springs and other coiled springs, but also springs and other articles made of steel, whether coiled, bent, twisted, or straight; that the same was old, well-known, and in common use or practice for many years prior to the alleged invention by Cary, and for more than two years before he filed his application for the patent; that said process or method had been so practiced on coiled springs, uncoiled springs, hard-drawn steel wire, and other articles of steel in various forms, for the purpose of increasing their elasticity; and that the patent was therefore void. It also set forth the names of many persons to whom the process described in the patent, whether considered as a restoring process or as a tempering process merely, was known, and by whom it was practiced, prior to the alleged invention thereof by Cary; and it averred that by reason of such prior knowledge and use the patent was void. It also averred that it was a common practice to subject furniture springs and other coil springs, made of hard-drawn steel wire, to 600x of heat, more or less, in the process of finishing such springs; that the same was practiced long prior to the alleged invention by Cary, by sundry persons, whose names were given in the answer; that there was not, at the time of the grant of the patent or of the alleged invention by Cary, any patentable novelty in the process described and claimed in the patent, or in the application of the process to the tempering of coiled springs for furniture, and that the patent was therefore void. It also set up various United States and English patents, and various printed publications, in which the alleged invention of Cary was said to have been described prior to the making of his alleged discovery and prior to his application for the patent. A replication was filed to the answer, and proofs were taken.

Prior to the filing of the bill in this suit, the patent had been sustained by a decision made by Judge Wheeler on February 7, 1885, in the circuit court of the United States for the southern district of New York, in Cary v. Wolff, 24 Fed. Rep. 139. On the basis of that decision a preliminary injunction was granted in the present suit by Judge Acheson on June 12, 1885. 24 Fed. Rep. 141. In Cary v. Spring Bed Co., in the circuit court for the district of New Jersey, on July 28, 1885, in a suit on the same patent, Judge Nixon, following Judge Wheeler and Judge Acheson, granted a preliminary injunction. 27 Fed. Rep. 299. On January 6, 1886, (26 Fed. Rep. 38,) Judge Nixon dissolved the injunction in the New Jersey suit, on the presentation of new affidavits relating to the novelty of the invention, and on February 2 1886, the preliminary injunction in the present suit was suspended on the giving by the defendant of a bond.

After the proofs were taken in the present suit, it was brought to a final hearing before Judges McKennan and Acheson, and they sustained the patent, following Judge Wheeler's decision. Their opinions are reported in 31 Fed. Rep. 344, 347. On August 3, 1887, the court entered an interlocutory decree, holding the patent to be valid and to have been infringed, awarding to the plaintiffs a recovery of profits and damages, with costs, referring it to a master to take the account of profits and damages, and granting a perpetual injunction. The master reported six cents damages and costs in favor of the plaintiffs. The plaintiffs excepted to his report, and the court, on a hearing of the exceptions, entered a final decree, on February 16, 1889, awarding to the plaintiffs a recovery of $8,745.34, and costs. The opinion of the court on the exceptions is found in 37 Fed. Rep. 654. The defendant has appealed to this court.

The invention claimed, as appears from the specification, is a method of restoring steel wire which has been mechanically strained, by subjecting it to a temperature of 600x, more or less, whereby its disturbed and disarranged molecules are allowed to assume their normal relation. The claim limits the method to its application to 'furniture or other coiled springs;' but it appears from the evidence that the process, as applied to those springs, is in no respect 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 claim covers broadly the described method of tempering applied to any coiled springs, as well as coiled springs for furniture, and, if the evidence shows that, prior to Cary's invention, the method had been used for the restoration of any springs of strained steel, or other articles of strained steel having the resiliency which is a well-known property of steel, the claim is substantially anticipated. Particularly if the method claimed had been used by others to restore articles of coiled spring steel, even though they were not used for furniture springs, the claim is anticipated.

In the testimony for the plaintiffs it appears to be contended that, in order to establish the charge of infringement, the patent is to be construed so as to cover the restoring of strained steel springs by the application of any temperature, less than a red heat, which will produce in the metal a blue color. If that be true, the patent must be so construed also in comparing it with the prior state of the art. Mr. Brevoort, an expert for the plaintiffs, says that if a coiled spring is attempted to be used, without further treatment, for a furniture spring, the wire will take a set, and lose its resilient properties, and its usefulness will be lost. He adds: 'To cure this defect the spring must be tempered, as it is called in the trade, and the way of doing this upon such springs constitutes the process of the Cary patent. The process described in the patent gives to the spring apparently the same qualities as would be imparted to steel by tempering; but I do not know that the process is really one of tempering, strictly so called, although it produces like results.'

The date of Cary's alleged invention is December, 1870, and the question is, what was the state of the art at that date? Mr. Brevoort explains 'the ordinary tempering process' as follows: ...