Grip Nut Co. v. MacLean-Fogg Lock Nut Co.

• Court: U.S. Court of Appeals — Seventh Circuit
• Writing for the Court: EVANS, PAGE, and SPARKS, Circuit
• Citation: Grip Nut Co. v. MacLean-Fogg Lock Nut Co., 41 F.2d 721 (7th Cir. 1930)
• Decision Date: 19 August 1930
• Docket Number: No. 4285.,4285.
• Parties: GRIP NUT CO. v. MacLEAN-FOGG LOCK NUT CO.

41 F.2d 721 (1930)

GRIP NUT CO. v. MacLEAN-FOGG LOCK NUT CO.

No. 4285.

Circuit Court of Appeals, Seventh Circuit.

May 29, 1930.

Rehearing Denied August 19, 1930.

Frank Parker Davis and George I. Haight, both of Chicago, Ill., for appellant.

Albert G. McCaleb, of Chicago, Ill., for appellee.

Before EVANS, PAGE, and SPARKS, Circuit Judges.

SPARKS, Circuit Judge.

This is an appeal from a decree of the District Court of the United States for the Northern District of Illinois dismissing the bill of appellant for want of equity. The controversy is the usual one arising where infringement of patent is charged. The patent alleged to have been infringed, invented by William E. Sharp for "Improvement in Lock-Nuts and Processes of Making the Same," is No. 1,271,782, and was granted to appellant July 9, 1918. The defenses presented were invalidity of the so-called Sharp patent and noninfringement. The lower court held there was anticipation of the invention by the disclosure of one Howarth's patent, No. 321,500, issued July 7, 1885; and, alternatively, that if Howarth did not strictly anticipate Sharp, appellee, in following the teachings of Howarth, did not infringe Sharp.

There were six claims under appellant's patent, and infringement is charged on the part of appellee as to each. Typical claims of appellant are No. 1 for the process and No. 6 for the device. They are as follows:

"1. The herein described process of producing a lock-nut consisting in forming a blank of substantially equal thickness throughout and solid except for the bolt hole with a centrally disposed rectangular shaped ridge of less width than the diameter of the bolt hole extending across one face thereof intersected by the bolt hole, and forming a thread in said nut, and thereafter placing the same upon a flat surface and applying pressure to the face of the ridge, whereby part of the threads in line with the ridge on each side of the bolt hole are modified, the compressed part of the topmost thread in each case being of a length substantially of the width of the ridge, and the compressed part of each succeeding modified thread being slightly less in length as they approach toward the other face of the nut."

"6. A lock-nut comprising a threaded bolt nut provided with a centrally disposed flat faced ridge across one face thereof severed by the bolt hole, the width of the ridge being less than the diameter of the bolt hole, the threads formed in the ridge being slightly compressed toward the other face of the nut, each succeeding thread of the nut beneath the ridge being likewise compressed, but successively shortened in length and disappearing within the body of the nut."

The claims under Howarth's patent, No. 321,500, are as follows:

"1. A nut or other analogous article which has internal screw-threads, having one or more of the convolutions of its screw-thread pressed or indented in the direction of the nut-axis, substantially as described, to form a locking device, whereby, when said nut is screwed onto a bolt or other analogous article having an external screw-thread, the indented portion of the thread in the nut will distort or force out of true pitch some portion of the convolutions of the thread on the bolt, as set forth.

"2. A nut or other analogous article which has internal screw-threads, having a lump or projection, d, formed on its face, in which a portion of the screw-thread is formed, whereby, when this lump or projection is hammered down, as described, in the direction of the nut-axis, the threads of the screw in the nut will be distorted, as and for the purposes set forth."

In describing the means by which his invention may be carried into effect, Howarth, among other things, says:

"One only of the projections d, or more, may be employed as desired, or a projection may be formed around the entire circumference of the edge of the hole through the nut at the outer face thereof when forming the nut-blank, and this projection be hammered or pressed down, so as to press down or indent the convolution or convolutions of the thread next to the outer face of the nut."

On September 8, 1887, British letters patent for "Improvements in Means for Preventing Nuts and Bolts from Working Loose," No. 12,174, were granted to one Bayliss, an associate of Howarth. We quote from the specifications of that patent:

"This invention relates to means of distorting some of the threads of a nut in order to prevent it working loose upon the bolt, or the bolt working loose therein.

"According to this invention the nut is formed of an inner end of the ordinary square or hexagon shape and of an outer end of a lesser exterior diameter, and preferably circular in shape, so as to form a shoulder between such parts; or, otherwise, the nut may be formed of the usual shape and recesses or notches be formed in the outer or top edge thereof so as to form shoulders at their lower or inner ends; and lumps are formed in the angles of the shoulder or shoulders and are forced into the solid metal of the nuts after the threads have been cut therein, by which means some of such threads are distorted and operate, as they are screwed upon the bolts, to firmly lock or hold the nuts upon the bolts; or instead of forcing in the lumps of metal as described the distortion of some of the threads may be effected by punching down metal in the shoulder or shoulders close up to the angle thereof. * * *

"The effect produced upon the threads of the nut by the forcing in of the lumps is not in all cases easily to be observed by the eye. * * * The downward distortion of the threads of the nut acts upon the threads of the bolt, as the nut is screwed up thereon, in a manner tending to force some of the threads slightly out of true pitch or gauge with the remaining threads of the bolt and thus causes the nut to lock firmly on the bolt. This action or result corresponds with that described, with reference to the locking of a nut upon a bolt, in the specification of an invention entitled `Improvements in means for preventing nuts and bolts or other screwed parts from working loose' for which Letters Patent were granted to William Bayliss and Robert Howarth dated the 12th May, 1884, Number 7589. The inward distortion of the threads, appears to take place more or less around the entire circuit of the threads, but chiefly at the parts thereof which are adjacent to the sites of the lumps, and the effect of such inward distortion is, obviously to cause the nut to bind or grip tightly upon the bolt and thereby increase its holding power. * * *

"In all these cases, though the exact effect on the threads of the nuts varies to some extent, the spreading of the metal consequent on the forcing in of the lumps or the punching in of the metal produces a distortion of some of the threads of the nuts which causes them to lock or bind tightly upon the bolts, and the nuts may be screwed and unscrewed upon the bolts several times in succession without material injury to the threads and still continue to bind tightly on the bolts."

It is observable from Bayliss's Fig. 1 that the lumps referred to are...