Rosenberg v. Shakeproof Lock Washer Co.

20 F. Supp. 959, 1937 U.S. Dist. LEXIS 1513
CourtDistrict Court, D. Delaware
DecidedAugust 13, 1937
DocketNo. 966
StatusPublished
Cited by3 cases

This text of 20 F. Supp. 959 (Rosenberg v. Shakeproof Lock Washer Co.) is published on Counsel Stack Legal Research, covering District Court, D. Delaware primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Rosenberg v. Shakeproof Lock Washer Co., 20 F. Supp. 959, 1937 U.S. Dist. LEXIS 1513 (D. Del. 1937).

Opinion

NIELDS, District Judge.

This is a patent infringement suit of Heyman Rosenberg, patentee, and ParkerKalon Company, exclusive licensee, against Shakeproof Lock Washer Company, defendant. The bill of complaint charges defendant with infringing patent No. 1,-809,758, granted June 9, 1931, for “Fastener” with all the claims in issue, and patent No. 1,827,615, granted October 13, 1931, for “Fastener” with claims 1, 2, 4, and 5 in issue. The bill further charges defendant with infringing the trade-mark “Self-tapping” of plaintiff. The defenses are invalidity and noninfringement.

Both patents relate to the type of screw employed for fastening sheets of metal together. After a hole has been bored to aid the screw in penetrating the metal, the screw wedges its way into the metal.

History of the Art.

Screws have been used for centuries. Their design and manufacture were well understood. Thread rolling was the most economical form of screw manufacture. Pointed screws rolled on curved dies were threaded to the end of the taper. A curved die fits a tapered blank. As you push the blank in you force the material into the grooves of the die. The height of the threads depends, upon the depth of the grooves of the die. This is the usual and very old way of making screws.

Blunt screws with ta'pering ends were frequently rolled on straight dies. This method of manufacture left the thread at the end incomplete and somewhat grooved. It is grooved because the action of the metal is to run up the sides of the grooves of the die and to leave a groove in the partially-formed thread of the screw.

White, the manager of an old screw company in Connecticut, deposed that when a tapered screw was ordered it was rolled on a straight die and the end was grooved. It was done without any intention of making a groove. The customer did not order the groove, but got it. The customer did not recognize any advantage in the groove because there was none. It was the economical and ’ standard mode of manufacture. The testimony of Cherry, another manufacturer, was to the same effect.

Before 1913, two types of screws were prevalent; the machine screw and the wood screw. The machine screw was made of metal with the threads close together. In using this screw the prevailing practice .was: (1) To bore a hole into the work; (2) to thread the hole’ with a tap; (3) -to insert the screw in the threaded hole and to screw tightly. The pressure could be increased by a nut applied to the projecting end. The wood screw was made of metal with the threads spaced some distance apart. It had a gimlet point so that it could be screwed directly into the wood; hence its name. Screws intended to go into wood without boring a hole had abrupt tapers. Screws intended to go into preformed holes had gradual tapers which kept them from canting.

In 1913, Rosenberg, the patentee in this case, applied for a patent on a screw herein called the A type screw. His patent solicitor allowed the application to lapse and it became abandoned. Three other applications were filed after the screw had been on the market. One application covered the screw. Another covered two pieces of metal fastened with the screw. The third application covered the method of putting it on. Patents issued before were held invalid because of the prior use by the inventor. Rosenberg v. Carr Fastener Co. (C.C.A.) 51 F.(2d) 1014. These patents involved the question whether it was invention to harden an old screw. All that Rosenberg did was to harden the threads of the old wood screw. When the patents were held invalid their subject-matter was disclaimed to the public. The public acquired the right to use a screw with hardened threads to crowd the metal out of the way and to embed the threads in the metal with the incidental advantage of holding under vibration. The public, of course, had and still has the right to make screws the way they have been made for years. This A type screw became and remains a part of the prior art

[961]*961A condensed statement with drawings may indicate the relation of the old screws of the prior art to the screws of plaintiff and the screws of defendant.

It appears that 3 or "A ' type screw had all the merits of “frictional hold,” “lateral pressure,” “crowding the metal back,” etc., claimed for the patents in suit.

Plaintiffs claim that patent 1,809,758 is particularly directed to putting the screw into thicker metal. The patent itself does not support that statement. Apparently the statement is based upon the following language of the specification: “Among the objects in view are: First, to facilitate entry of the rib or thread to relatively great depth in the work with less resistance,” etc. This evidently means trying to make the thread bite into the work laterally as far as possible. Penetrating thicker metal was not intended. This appears from other quotations from the specification: “Since the improved fastener is designed and adapted especially for use in metallic work, and particularly relatively thin material,” and “Fasteners embodying the invention are at present extensively and successfully used for connecting sheet metal of eighteen gauge to sheet metal of fourteen guage,” etc. There is no basis in the patent for the suggestion that it is directed to screwing thick metal.

[962]*962Patent No. 1,809,758 is directed entirely to the supposed merit of the groove in the thread. For this groove the patent claims two advances: (1) The pincher effect; and (2) facilitating the entry. Both are found in the following extract from the specification: “When the pilot 6 has entered the aperture in the work sufficiently for the entering termini of the edges 4' to contact with the work, the fastener or screw is revolved, as by the use of a screwdriver or like instrument engaging the kerf 3, and the said edges 4' enter the metal and form therein spaced grooves which are the beginnings of an internal thread. Owing to the location and form of the upper or longer edge 4', the entered material will be caused to flare upwardly, that is, in the direction of the length of the fastener or screw toward the head thereof, as clearly indicated in Figure 4. The continued rotation of the screw or fastener causes the entering ends of the edges 4' to pass on through the material of the work and beyond the same (when the work is of relatively thin sheet material), the said edges in passing through the last portions of the material of the work causing said material to flare in the direction of the length of the screw or fastener toward the pilot 6 which has passed beyond the work, so that the'material of the work has the effect of having been thickened about the fastener and an additional purchase for the fastener is thus provided. Continued rotation of the fastener or screw causes the material of the engaged work to flow to successive positions, as indicated respectively in Figures 5, 6 and 7. As the thread or rib advances the bottom or base of the valley or groove 5 between the edges 4' outstands more and more and begins to crowd the material of the work lying in the groove outward in a direction away from the axis ,of the screw. This outward crowding action is also accomplished by a-pincher action incident to the fact that the groove grows narrower .as it grows less in depth, and the material of the work is thereby caused to flow into a more compact condition, which compact condition is indicated by the stippling at 12 in Figures 1, 5, 6 and 7.

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Related

Dietene Co. v. Dietrim Co.
121 F. Supp. 785 (D. Nebraska, 1954)
Rosenberg v. Shakeproof Lock Washer Co.
100 F.2d 811 (Third Circuit, 1938)

Cite This Page — Counsel Stack

Bluebook (online)
20 F. Supp. 959, 1937 U.S. Dist. LEXIS 1513, Counsel Stack Legal Research, https://law.counselstack.com/opinion/rosenberg-v-shakeproof-lock-washer-co-ded-1937.