Diamond Expansion Bolt Co. v. Parker Supply Co.

228 F. 205, 1915 U.S. Dist. LEXIS 982
CourtDistrict Court, S.D. New York
DecidedDecember 6, 1915
StatusPublished

This text of 228 F. 205 (Diamond Expansion Bolt Co. v. Parker Supply Co.) is published on Counsel Stack Legal Research, covering District Court, S.D. New York primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Diamond Expansion Bolt Co. v. Parker Supply Co., 228 F. 205, 1915 U.S. Dist. LEXIS 982 (S.D.N.Y. 1915).

Opinion

I,EARNED HAND, District Judge.

Claim 1 provides that the screw shall engage the interior cavity through only a small portion [206]*206of pts periphery which is to be threaded by tire screw. This is explained by the figures themselves. The slots, c, c, of the patent meet the sides of the square interior section of the shield and result in leaving of the interior cavity only the corners of the shield. • Thus there results a narrow rib having a groove within it, the four grooves and four slots together making eight ribs, which are described in the patent. The periphery of the screw as it enters the cavity is therefore touched by only these four ribs, which engage but a very small percentage of that periphery- In the defendant’s shield the screw from the very outset touches the whole inner cavity, except where the two slots cut it, which amounts in all to only about one-twentieth of the total interior of the cavity. Now it is quite true that as the shield expands the slots will widen, and the screw will engage the interior of the cavity’for a less and less portion of its periphery. If the claim could be confined, therefore, to the inward end of the shield, it might have some application to the defendant’s shield; but if it be conceived in this way the claim would cover any slotted expansible bolt that could be devised, for the expanding of the shield inevitably opens the slots and permits the bolt to engage a smaller percentage of the inner cavity. The claim cannot, therefore, be construed in that way. It must mean that the screw engages the interior cavity with only a small portion of its own periphery as soon as it begins to engage the shield at all.

Claim 2 contains as an element “interior projections arranged to form the seat for a bolt.” By the phrase “interior projections” is clearly intended projections into the interior cavity. In the defendant’s shield the interior cavity is conical, and therefore each section is a circle. It is an abuse of language to speak of those circles as being projections. However many slots are made in the shield, the resultant section will remain circular, and will have no projections within its circumference. The patentee clearly intended projections into interior cavity itself, for he said on page .1, lines 87-99:

“Its threads engage the projections formed on the members or sections, 5, and on the interior of the square hole D, into which the threads- of the screw readily bite and render it easy to drive such screw in. The threads of the screw engage with the interior of my shield through only a small portion of the periphery of such screw, since, as is indicated in Fig. 2, the ribs or projections extend over only a small portion of the interior surface of the shield, where they would engage a screw inserted into the shield to form a seat or support for the screw.”

The purpose of the patentee seems in part to have been by reducing the area of the shield which the threads of 'the screw must cut, to diminish the pressure on the outside of the shield. Page 2, lines 7-10. This could be accomplished only in case the threads engage the interior of the shield over only a small portion of their periphery. It is of no consequence whether in fact he was deceived in this expectation or not. The plaintiff’s expert does testify that .the thread cuts deeper than the projections and into the full body of the cavity, but that obviously depends upon the resistance of the expansion shield, which may arise from the rigidity of the shield itself or from the pressure exerted on its exterior. The idea that the ribs [207]*207project into the interior cavity is further manifested in the possible alternatives indicated in the patent (page 2, lines 49-59), where the patentee says that the ribs may be formed in any other manner if they be of relatively small area, and further says that their number, form, or contour might be varied, provided they exercised a comparatively gentle action. This gentle action again reflected the idea mentioned above, that by reducing the proportion of the interior cavity which the threads must cut the external pressure will be reduced.

There is, indeed, one most strained interpretation which can be placed upon this language, and which would answer, which is to regard the mere conical shape of the interior cavity as resulting in projections into its own interior. If one looks into the large end of a cone, all portions away from the eye project into the cavity as it were; only in case the cavity be cylindrical would there be no projections into the far end. To divide such a cavity into two sections by two slots makes each of these sections project into a cavity so considered, This, however, is no more than to say that the cavity is itself conical, which is certainly not the intention of the patent. Indeed, the patent itself seems to contemplate the possibility of a cylindrical inner cavity, for the patentee (page 2, lines 64-72) suggests that the shield may be either cylindrical or tapering, with a corresponding interior cavity, although to secure the desirable effect of a greater expansibility at the rear the radial thickness of the rear walls should be greater than those of the front. However, even though this were the intention of the patent, it could not constitute patentability, for a conical interior cavity had been shown in the art before. McCreery, No. 623,809, is such a disclosure, although the threads of the bolt do not cut into the conical cavity and the expansion of the bolt is intended only as a means of holding the whole shield in place. Cook’s former patent, also, has such a cavity. It is true that the conical portion of the cavity appears to have been only toward the end, but there could be no patentability in extending the slots further toward the front and making the cavity taper where the slots begin.

Claims 3 and 5 do not require any consideration, other than that given to claim 2, for they each use the words “interior projections arranged to form the seat for a bolt inserted into said block.”

Claims 10, 11, and 14 vary the language somewhat, speaking of “ribs formed upon the slotted portion of said shield and adapted to engage the threads of said bolt or of ribs or projections.” The term “ribs” is quite clearly the equivalent for the “interior projections” mentioned in claims 2 and 3, and requires no further consideration than that given to claim 2. The words “adapted to engage the threads of the bolt” I do not understand to mean anything different from the phrase “arranged to form the seat for a bolt.” It is true that the plaintiff lays some emphasis upon the language in the specifications on page 2, lines 37-46, in which the longitudinal grooves mentioned in the patent are said to be adapted to guide the screw or bolt inserted into the shield in a more accurate manner. The reason given by the patentee for this result is that, owing to the grooves, the screw is engaged by each rib at two points, which prevents its displacement. [208]*208There really is very little in this contention. If the ribs were not grooved, and were all equally distant from the center of the cavity, the screw would be equally well guided in its true axial position as though the rib had a small groove. However, the language has application only to a form in which there are in fact ribs projecting into the cavity, each of which has a groove. It can have no application to a device in which there are no ribs projecting into the interior cavity at all.

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Bluebook (online)
228 F. 205, 1915 U.S. Dist. LEXIS 982, Counsel Stack Legal Research, https://law.counselstack.com/opinion/diamond-expansion-bolt-co-v-parker-supply-co-nysd-1915.