Lourie Implement Co. v. Lenhart

SANBORN, Circuit Judge.

This is an appeal by the Eourie Implement Company, a corporation, from a decree that it has infringed the first and second claims of letters patent No. 415,542, to John Eenhart, for a new and useful improvement in plows, and that it must cease its infringement.

The patented device is a slotted slide-plate adjustable to the inner side of the heel of the share or moldboard of an ordinary walking plow to hold the plow level, to regulate its tendency to tilt to the side of the moldboard, and to preserve the outer edge of the share from wearing off while other parts of it are in a better condition. The slide-plate is held in place by a bolt which passes through the moldboard and through the slot in the plate, and is secured by a nut. By loosening the nut the plate may be depressed so that its lower edge will register with, or extend under the edge of, the share, or it may be raised so that its lower edge will be above the edge of the share. The depression of the plate brings it below the plane formed by the lower edges of the landslide and the plowshare, places it in contact with the bottom of the furrow on the moldboard’s side of the plow, and in this way it prevents the plow from winging down, or causes it to tilt toward the landside. By the use of the bolt and slot, the plate may be adjusted to keep the plow level, and to overcome any tendency which it may have to wing down or or to wing up.

In his specification the patentee describes a slide-plate, the lower edge of which is thin and is turned out, and which may be adjusted so far above the edge of the plowshare that it will not extend down to the lower plane of the plow, and will not affect its operation, or it may be dropped so low that its lower edge will extend under the edge of the plow, and engage the bottom of the furrow. He states that the objects of his invention are to prevent the plow from winging down, and to preserve the heel of the share from wear. In the latter portion of his specification he states that the lower edge of the plate is also found to be especially useful when it projects under the edge of the share in cutting the roots under the sod. He describes a plate with a gradual taper from the slot to its lower sharp edge, but declares that he does not confine his invention to any particular form of the lower portion of the plate, and that it may be made of any desired construction, so that it will adjust the required degree of elevation of the moldboard’s side of the plow, and protect it from wear, and furnish a cutting adjustable edge projecting beyond the share. The first and second claims of the patent read in this way:

“(1) The combination, with a plow, of an adjustable plate working under the edge of the share to raise or lower the share to keep the plow level and from tilting over, and the share from wear, as and for the purpose set forth.

“(2) The combination, with a plow, of an adjustable slide-plate secured to the inner side of the share by a bolt, said plate conforming to the contour of the share, and adapted for adjustment under its edge to raise or lower the share to keep the plow level and from tilting over, and the share from wear, as and for the purpose set forth.”

The appellant calls its device a “shoe.” It is a slotted sliding plate attached to the clip or brace on the inner side of the moldboard of the plow by means of a bolt which extends through the moldboard, the clip, and the slot in the slide, and is fastened by a nut. By means of this bolt and slot the appellant’s slide is so adjustable that it may be depressed so far that its foot will extend below the plane of the lower edges of the landside and the moldboard of the plow, and will engage the bottom of the furrow. In this position it will counteract the tendency of the plow to wing down, and prevent the wear of the edge of the moldboard to some extent by holding it up from the bottom of the furrow. By means of the bolt and slot the counteracting tendency of the slide may be adjusted to the strength of the tendency of the plow to wing down. While the appellant accomplishes in this way the objects which Tenhart declares in his specification he made his invention to attain, to wit, the regulation of the tilting of the plow, and the prevention of the wear of the share, the appellant gives a different form to the lower part of its device, so that it does not pass under the edge of the plowshare, and does not cut the roots of the grass. Instead of making the lower part of the slide thin, and turning it out, so that, as it is depressed, it will pass under the edge of the plowshare and cut the roots, the appellant thickens, widens, and flattens the lower part of its slide into the form of a triangular shoe, and, by means of clamps extending from the slide to the clip or the moldboard, holds the foot of it about seven-eighths of an inch away from the edge of the plowshare when it is extended below the plane of the bottom of the plow. The appellees make their plows so that when they are new they will run level, or will not wing down, and as the shares wear away they adjust their sliding plates to counteract the tendency of the plows to wing down, and thus keep them level. The appellant makes its plows so that without the sliding plate or shoes they have a strong tendency to wing down when they are new, and puts its sliding plates or shoes at once into operation to counteract this tendency, by extending the feet of them below the planes of the bottoms of the plows when they are first put in operation.

The appellant insists that its device does not infringe upon the claims under consideration, because it does not cut the roots of the sod, and because when it is depressed it does not pass under the lower edge of the plowshare, although it passes below the plane of that edge upon the side of it. In support of this contention, it insists that the invention of Lenhart is so limited by the prior art that, if its machine infringes, his invention is anticipated and the patent is invalid. The principle of Lenhart’s invention is the regulation of the tilting of the ordinary walking plow by means of an adjustable sliding plate attached to the under side of the moldboard or share of the plow. Its mode of operation consists in the adjusting of this plate by sliding it up and down by means of the slot, the bolt, and the nut, so that the plow will run level. The patents which counsel for the appellant cites to show that this principle and mode of operation, which the appellant has clearly embodied in its sliding shoe, were disclosed before Lenhart invented his plate, are No. 226,750, to F. Simonds, April 18, 1882; No. 274,491, to W. K. Harrell, March 27, 1883; No. 397,891, to A. F. Bjorkstrom, February 19, 1889; No. 336,946, to F. Reyner, March 2, 1886; and No. 263,637, to W. J. N. Welborn, August 29, 1882. The patents to Simonds and Harrell do not describe sliding plates upon the moldboards of plows, but shoes beneath the plows, upon which they bear when in operation; and these shoes lack the essential principle of Lenhart’s invention — its adjustability to the changing tendency of the plows to tilt toward the side of the moldboards. The patent to Bjorkstrom shows a plow provided with two shoes — one under the heel of the land-side, and the other under the heel of the moldboard. The shoe under the heel of the moldboard consists of a small, tapered plate, pivoted at its front end to the inner side of the moldboard, with its rear end adjustable vertically by means of a slotted ear which operates upon a bolt in the moldboard of the plow. The forward end of the tapered shoe cannot be raised or depressed without removing the entire shoe from the plow. This device therefore lacks the requisite adjustability which the sliding plates of Lenhart and the appellant possess, by means of which the entire plates may be raised or.depressed without detaching them from the plows. •> Bjorkstrom’s device was not conceived or constructed to regulate the tilting of the plow toward the side of the moldboard, but to serve the same purpose that the shoe on the landside of his plow was made to serve — the purpose of shoes on a sled. It was made to be what Bjorkstrom calls it — a wear-plate. When the appellant adopts the shoe of Bjorkstrom, it will not infringe the patent to Lenhart, because it will not then accomplish the purpose which his invention was made to attain, and will not avail itself of the principle which Lenhart’s device involves. It may be that it is because it seeks to attain that purpose that it has neglected Bjorkstrom’s pivoted shoe, and appropriated Lenhart’s sliding plate. The patents to Welborn and Reyner have little relevancy to the issue in this case. The former describes a guide, and the latter a stirring attachment to a plow. Neither of the patents discloses an adjustable sliding plate for regulating the tilting of the plow, or any other equivalent means for accomplishing that purpose. This brief review of the patents cited by counsel for the appellant discloses the fact that there is nothing in them which describes or suggests the adjustable sliding plate of Lenhart; no description of any device which will accomplish the purpose of his invention; nothing that places the adjustable, slotted, sliding plate of the appellant, with its blunted, flattened lower edge, beyond the limits of the grant to Fenhart, or that relieves the Fourie Company of the infringement of which the court below found it to be guilty.

But counsel for the appellant persuasively argues that his client does not infringe upon the grant to Fenhart, because the only device secured by the first and second claims of the patent to him is an adjustable plate which slides under the edge of the share to raise or lower it', and which cuts the roots beneath the turning turf, and that the sliding plate of the appellant never projects under the edge of the share, and never cuts the roots beneath the sod. This construction of the two claims of the appellee which have been quoted, however, does not commend itself to our judgment. It is too narrow, refined, and technical. It permits a nullification of the grant by a mere change of the form of the foot of the device from a sharp, turned edge, to a blunted, straight edge, while the changed machine retains the principle and the mode of operation and performs the function sought and secured by the patented device. Grants of letters patent should receive a- fair interpretation — one that vitalizes rather than one that paralyzes them. If the sliding, adjustable plate of the appellant had been disclosed in the prior art, and if the only novelty or patent-ability of Fenhart’s device consisted of the special form of its lower edge, whereby it was adapted to pass under the edge of the plowshare and to cut the roots of the grass, his patent might be limited to a slide of that specific form. Sandwich Enterprise Co. v. Joliet Mfg. Co., 33 C. C. A. 491, 493, 91 Fed. 254, 256; Campbell v. Richardson, 76 Fed. 976, 22 C. C. A. 669. This, however, was not the case. No one before Fenhart regulated the tilting of the ordinary walking plow by an adjustable sliding plate on the inner side of the moldboard or share. He discovered the principle and the mode of operation by which he has effected this regulation. He was the original inventor of the slotted sliding plate, by means of which the desideratum he sought was first attained. The purpose of the plate and of the invention was not to cut the roots of the grass beneath the sod, but to regulate the tilting of the plow. The cutting of the roots was but an incident of the particular form of the plate which Fenhart described. But that form was not the essence of his invention, and it is neither mentioned nor claimed in either of the two claims of the patent which are here in litigation.

May the appellant escape liability for infringement because, instead of making the foot of its adjustable plate thin, and bending or turning it toward the plowshare, so that in operation it would pass under it and cut the roots of the grass, it has made it thick and blunt, and extending vertically downward below the plane of the plow seven-eighths of an inch distant from, and on the side of the edge of, the plowshare? Mere changes of the form of a patented device, where the principle or mode of operation is adopted, will not avoid infringement, unless the form of the machine is the distinguishing characteristic of the invention. National Hollow Brake Beam Co. v. Interchangeable Brake Beam Co., 106 Fed. 693, 711, 45 C. C. A. 544, 562; Kinloch Tel. Co. v. Western Electric Co., 51 C. C. A. 362, 365, 113 Fed. 652, 655. The distinguishing characteristic of this invention was not the thinness or bend of the sliding plate, but its position and adjustability upon the moldboard.

A copy of the thing described in a patent, either without variation, or with such variations as are consistent with its being in substance the same thing, is for all the purposes of the patent law the same device as that described in the patent. Burr v. Duryee, 1 Wall. 531, 573, 17 L. Ed. 650. One who claims and secures a patent for a new machine thereby necessarily claims and secures a patent for every mechanical equivalent for that device, because, within the meaning of the patent law, every mechanical equivalent of a device is the same thing as the device itself. A device which is constructed on the same principle, which has the same mode of operation, and which accomplishes the same result as another by the same means, or by equivalent mechanical means, is the same device, and a claim in a patent of one such device claims and secures the other. Machine Co. v. Murphy, 97 U. S. 120, 125, 24 L. Ed. 935. The sliding, slotted, adjustable plate of the appellant, with its thickened, flattened lower edge or foot by the side of, and seven-eighths of an inch distant from, the edge of the share of the plow, involves the same principle, has the same mode of operation, and performs the same function — the regulation of the tilting of the plow — by mechanical means equivalent to the adjustable sliding plate of Lenhart, with its thin edge bent against the plowshare so that it may slide under its edge when it is depressed below it. One may not escape infringement by adding to or subtracting from a patented device, by changing its form, or by making it more or less efficient, while he retains its principle and mode of operation, and attains its result by the use of the same or of equivalent mechanical means. Walker on Patents, §§ 347, 348; Sewall v. Jones, 91 U. S. 171, 183, 23 L. Ed. 275; Coupe v. Weatherhead (C. C.) 16 Fed. 673, 675.

The decree below is affirmed.