Appeal from the District Court of the United States for the Northern District of Illinois, Eastern Division, John P. Barnes, Judge.
Before ALSCHULER and SPARKS, Circuit Judges, and LINDLEY, District Judge.
Appellant brought suit upon three patents to Harold A. Clark, Nos. 1,807,567, claims 1 to 10; 1,807,569, claims 1 and 2; 1,819,871, claims 3 and 4. The District Court found that the first-mentioned patent is invalid for lack of invention; that one Roed was the first inventor; and that the patent if valid is infringed. The court found the last two mentioned patents invalid for lack of invention, but, if valid, infringed by certain of defendant's devices. From a decree dismissing its bill of complaint for want of equity, appellant appeals.
These patents relate to oil seals which are used within bearings or housings of rotating parts, chiefly in automobiles and other machines employing axles and shafts, to prevent oil from escaping. Oil readily seeps through the most minute openings, and devices have long been used to furnish a seal in such places as the rear axle of an automobile which revolves within a housing upon bearings completely surrounded by oil.
The first patent covers a self-contained, unitary oil seal structure, having a cup-shaped outer member, which is closed by a washer, and having within the inclosure of the cup a sheet leather packing member comprising a barrel portion, which embraces the shaft, and a flat radial flange portion which is placed flatly against the bottom wall of the cup and hugs closely the axle or shaft. The outer cup, in turn, contains a pressure transmitting shell in the form of an inner cup located between the washer and the leather flange. The bottom of this inner cup presses closely against the flange and permanently presses the flange against the bottom wall of the outer cup. Encircling the leather flange and between it and the washer is an endless coil spring which constricts the leather. The device efficiently prevents leakage of oil. The structure is clearly shown in the description and specifications as well as the claims, of which No. 7 it will be sufficient to quote:
"In a seal, a cup-shaped cage, a cup-shaped ring nested within the cage, a flanged packing having axially and radially extending portions, said packing being positioned in the case with the radially extending portion of the packing clamped between the bottom of the cage and the bottom of the ring, a coil spring positioned under tension within the ring about the axially extending portion of the packing, and a washer positioned under pressure within the cage against the rim of the ring in loose engagement with one side of the spring."
That the device has been successful is shown by the fact that it was promptly adopted by the automobile industry and superseded every prior device for like sealing. Prior to the trial, appellant had produced and sold over 44,000,000 seals, and 80 per cent. of all automobiles manufactured in the last few years have been equipped with them.
The narrow questions submitted are whether Clark was the first inventor and whether the invention is anticipated by the prior art.
Appellee relies upon two devices not patented, namely, those of Tinken and Hupp, which, for the purpose of this discussion, are equivalent. The Timken device made use of a cup-shaped casing, but the cup in reality had no bottom against which the flange of the leather packing bore. Rather, it made use of a narrow annular inset shoulder against which the outer marginal portion of the flange of the leather packing was clamped by a washer set within the cup. The washer had a flange which extended axially substantially to the edge of the cup. The flange of the washer and the cup formed a metal-to-metal contact which was not efficient as an oil-tight seal because of distortion of the metal due to peening and press-fitting operations. The result was oil leakage throught the imperfect joint. While it is true the structure clamps the extreme outer edge of the flange, the pressure was applied some distance radially from the shaft and the clamping effect was not sufficient to prevent leakage. Furthermore, this device could be utilized in only a relatively large space, as the inset shoulder had to be formed in the outer cup radially beyond the portion of the outer cup which contained the spring. Consequently, the diameter to which the outer cup could be reduced for any specified shaft was necessarily comparatively limited. In other words, the device could not be made small enough to fit in the small clearance spaces for seals in the modern automobile.
The appellee relies upon Aschenbach patent No. 1,507,567. That did not cover a self-contained device like that of appellant. It was necessaary that its parts be built up or assembled when it was put in place. The clamping pressure on the leather packing was not inherent, therefore, in the structure itself, but such pressure could be produced only by the wheel on the axle bearing against the outer metal shell of the device. Consequently, if wheel clearance developed between the shell and the wheel by wear, after short use, any pressure effect on the leather was lost and the shell became froo to assume a position where it did not even come in touch with the leather. There was, therefore, no degree of permanency in the sealing effect.
Appellee rebuilt one of Aschenbach's structures, but in doing so, it lost Aschenbach's idea, destroyed the original structure, and rebuilt according to the teachings of Clark. Aschenbach did not teach the essential use of an inner shell as a device for clamping the leather within a self-contained structure.
We find nothing in the Timken structure, which has been abandoned, or in the Aschenbach patent, which was never in use, by which Clark was taught how to achieve what he has accomplished in his patent.
Clark had previously made a similar device under patent No. 1,674,762, which met with success, more than a million of them having been made. But this, too, had its defects. It was small and lessened the amount of leakage found in prior seals. It was defective in that the spring was required to perform the dual function of constricting the barrel of the packing member around the shaft and pressing the flange of the packing member against the bottom of the cup. In order to achieve its dual function, the spring had to fit the space between the washer and the packing flange, but in practice and in use it was found that this pressure lessened, because the coils of the ...