Continental Farm Equipment Co. v. Love Tractor

• Decision Date: 22 October 1952
• Docket Number: No. 14385.,14385.
• Citation: 199 F.2d 202
• Parties: CONTINENTAL FARM EQUIPMENT CO., Inc. v. LOVE TRACTOR, Inc.
• Court: U.S. Court of Appeals — Eighth Circuit

199 F.2d 202 (1952)

CONTINENTAL FARM EQUIPMENT CO., Inc. v. LOVE TRACTOR, Inc.

No. 14385.

United States Court of Appeals Eighth Circuit.

October 22, 1952.

I. Joseph Farley, Detroit, Mich. (Farley, Forster & Farley, Detroit, Mich., on the brief), for appellant.

Eugene C. Knoblock, South Bend, Ind., for appellee.

Before SANBORN, JOHNSEN, and COLLET, Circuit Judges.

COLLET, Circuit Judge.

The plaintiff, Love Tractor, Inc., brought this action in the District Court for the District of Nebraska to restrain the defendant, Continental Farm Equipment Company, Inc., from infringing plaintiff's patent No. 2,320,624 on a disc harrow, and for damages for past infringement. Defendant answered that plaintiff's patent was invalid for want of invention, that the disc which defendant was making and selling did not infringe, and counterclaimed for damages to its business resulting from plaintiff's notices to its customers to cease selling implements infringing plaintiff's patented product. After trial and an inspection of plaintiff's disc and defendant's accused implement, the trial court held plaintiff's patent valid and infringed, issued the injunction requested, dismissed defendant's counterclaim and retained jurisdiction for the purpose of determining plaintiff's damages in the event they were not agreed upon. It is from that judgment that this appeal is prosecuted.

The principal question for decision is the validity of plaintiff's patent. It is assailed upon the ground that plaintiff's implement is really only an aggregation of three principles demonstrated by prior patents and past uses, combined by plaintiff by the application of mere mechanical skill and without need for or resulting from inventive genius. There is no real difference between the parties concerning the applicable law by which invention is distinguished from mechanical skill, although there is a difference of opinion as to the application of the rule laid down in Cuno Engineering Corp. v. Automatic Devices Corp., 314 U. S. 84, 62 S.Ct. 37, 86 L.Ed. 58, Great A. & P. Tea Co. v. Supermarket Corp., 340 U.S. 147, 71 S.Ct. 127, 95 L.Ed. 162, and related cases, to the facts of this case. The controversy necessarily requires a scrutiny of plaintiff's patent in the light of the prior art and former uses of the constituent parts of plaintiff's product.

Plaintiff and defendant refer to the implement involved as a disc harrow. We shall call it a disc. It is a farm tool used for the cultivation of the soil. For many years, discs have been used on the farm. Both before and after the use of tractors they have been pulled over the ground to cut and loosen the top soil or to serve the same function after plowing. The old-style discs were constructed by threading saucer-shaped steel discs with sharp outside cutting edges on a steel shaft with spacers between each disc. We will refer to such an accumulation of parts as a gang or section. An implement called a single disc consists of two of these gangs placed end to end and held in that position by an appropriate frame. On many of the old types the outer ends of each gang were pivoted so that the inner ends of each gang could be moved forward or backward by means of a lever so that the two gangs would have the shape of a flattened "V" () When the gangs were in that position the disc penetrated the soil deeper and also turned it as the implement was pulled through the soil. This characteristic of the inner end of the gangs being susceptible of being moved backward or forward is called "adjustability" by the parties. On many of the old types the outer ends of each gang were also pivoted in such a manner as to permit each gang to tilt on its horizontal axis, enabling the inner end of each gang to move up and down. This was for the purpose of permitting each gang of the disc to follow the contour of the ground it was passing over and to cultivate it evenly although the surface of the soil might be uneven. This characteristic is called "floatability." Tandem discs consist of two pairs of gangs, one pair behind the other, for the purpose of doubly cultivating the soil in one operation. Although defendant manufactures and sells both a single and tandem disc, after the inspection and demonstration of both during the trial, plaintiff withdrew its charge of infringement insofar as the defendant's tandem disc was concerned. Defendant's single disc remains as the accused device.

After tractors came into use, for a long time they only pulled farm implements such as plows, discs, and harrows over or through the soil without undertaking to lift the entire implement off of the ground. In time a device was put into use by tractor manufacturers which was built into the tractor and by the application of a hydraulic apparatus would lift rigid implements such as a plow entirely free from the ground. This was accomplished by attaching the plow by hinges to a rigid draw bar fastened to the rear of the tractor comparatively low and near the ground, then attaching to the top of the frame of the plow or other implement a frame of strong material in the shape of an "A" () with the legs of the "A" attached to each side of the frame of the implement and a brace from the top or apex of the "A" rearward and downward to a point on the rear part of the frame of the implement. When a drawbar was then attached to the front of the top or apex of the "A" and by the hydraulic device on the tractor this drawbar was pulled forward, the entire implement was raised and held in suspension on the hinges attached to the lower drawbar and by the hydraulic lifting device above. The characteristic of being susceptible of being lifted free from the ground is called "liftability."

Mr. Love was a tractor and farm implement dealer. He conceived the idea of making a disc which would have both the adjustability and floatability of the old discs, and also be liftable, like plows and other rigid implements. The principal problem to overcome in order to accomplish this was to so devise the disc as to permit it to be lifted without having the movable inner ends of the section sag down and not leave the ground when the implement was lifted. He accomplished that...