Brown & Sharpe Mfg. Co. v. L. S. Starrett Co.

225 F. 993, 1912 U.S. Dist. LEXIS 1857
CourtDistrict Court, D. Massachusetts
DecidedNovember 13, 1912
DocketNo. 77
StatusPublished
Cited by2 cases

This text of 225 F. 993 (Brown & Sharpe Mfg. Co. v. L. S. Starrett Co.) is published on Counsel Stack Legal Research, covering District Court, D. Massachusetts primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Brown & Sharpe Mfg. Co. v. L. S. Starrett Co., 225 F. 993, 1912 U.S. Dist. LEXIS 1857 (D. Mass. 1912).

Opinion

BROWN, District Judge.

The bill charges infringement of letters patent No. 717,296, December 30, 1902, to F. Spalding, assignor to Brown & Sharpe Manufacturing Company, for micrometer' calipers. The specification states:

"This invention has reference to an improved device for clamping the spindle of a micrometer caliper or gauge.
•‘Micrometer calipers or gauges consist usually of a frame having an anvil’ at one end and a spindle partly screw-threaded and in screw-thread engagement with the opposite end. These calipers or gauges are used in the arts for the accurate measurement of parts and are usually constructed to determine microscopic differences within one Vtooo of an inch. When the accurate measurement has been taken by a micrometer caliper or gauge, it is desirable to lock the spindle, so as to retain the exact position of the same. To lock the spindle and maintain the same in the position when .the measurement is taken, it is important that the spindle should not be rotated or moved longitudinally in the slightest degree, so that the measurement taken will not be altered.
"The invention consists in the peculiar and novel construction of a split-spring clamping-ring, and means for actuating tho same, as will be more fully set forth hereinafter.”

The means for locking the spindle consist of a split clamping-ring arranged to surround the spindle, the clamping-ring having an inclined [994]*994or tangential surface; an actuating-ring surrounding the clamping-ring ; a roller interposed between the split-ring and the actuating-ring and located in the space formed by the inclined or tangential surface; and a projection upon the split-ring which engages a slot in a portion of the frame which forms the bearing of. the spindle. The projection and slot prevent the split-ring from turning with the actuating-ring.

These parts are placed in a transverse slot formed in the micrometer frame or spindle bearing.

The specification states:

“The split-ring 6 may now be placed into the actuating-ring c, the member 6 s in the wedge-shaped cavity between the split-ring and the actuating-ring, as is shown in ITig. 3, and the assembled parts may be slid into the slot a*, with the projection 6i in the seat e2. The spindle is now placed in position, extending through the split-ring, which ring is held against rotation.”

The spindle may be locked by rotating the actuating-ring, thereby moving the roller toward the split-ring, to contract the ring and clamp it on the spindle. It may be released by the reverse movement of the actuating-ring.

The complainant contends that the advantage of this construction is the effective locking of the spindle without any disturbance of its adjusted position, and the further advantage of ease of assembling the parts and of removing the same, if desired.

The claims in suit are:

“1. The combination with the spindle of a micrometer caliper, the bearing of the spindle, a transverse slot in the bearing and a cavity in the wall of the bearing, of a split-ring, a projection on the split-ring, a tangential plane on the split-ring, an actuating-ring inclosing the split-ring, and a member operated by the actuating-ring and operating the split-ring, as described.
“2. In a micrometer caliper, the combination with the frame of the caliper, the anvil, the spindle, the bearing for the spindle, and the micrometer mechanism, of the slot a?, the seat e2 in the wall of one side of the slot, the split-ring 6, the projection 6i on one face of the split-ring, the plane 62 and shoulder 6*, on the split-ring, the member 6s, and the actuating-ring c\ as described.” '

The defendant contends that the device shown in the patent is lacking in patentable novelty, and shows that the priqr art contains a number of patents showing micrometer calipers or gauges with means for locking the adjusting screw or spindle in position. The patents cited are: Starrett, No. 433,311; Spalding, Nos. 557,445 and 645,838; Bellows, Nos. 456,875 and 612,601; Wells,_ No. 641,173. _

_ A transverse slot in the frame of a miscrometer caliper to receive an actuating-ring, for controlling a locking mechanism, is shown in patents to Bellows, No. 612,601, and to Wells, No. 641,173. There is also evidence that this feature of construction was shown in calipers made by Starrett in 1898. In none of these patents, however, nor in the Starrett micrometer caliper' in evidence, is found the clamping or locking means of the patent in suit. ' The defendant contends, however, that brakes and clutches, with a split-ring with tangential surfaces with rollers or balls, were in use, and that these clutches ate similar in construction and principle to that of the patent in suit.

Special reliance is placed upon the patent No. 613,619, November 1, 1898, to F. L,. Clapp, for back-pedaling brake.

[995]*995The. principal proposition of the defendant is that, micrometer gauges having been used with some form of clutch for locking an adjusting screw in position, there was no invention in substituting one old form of chuck in such connection in place oí a clutch heretofore used on micrometer gauges. It is argued that the idea of applying a clutch to a multiplicity of objects is inherent in the very nature of a clutch. This argument assumes that only the ordinary considerations applicable to clutches or brakes in general are applicable to the problem of the patent in suit. The patents of the prior art show a number of attempts at a solid ion of the problem of providing an efficient and convenient locking deuce for a micrometer caliper. In the general art of clutches or brake,s there existed the problem of firmly engaging a shaft, but it does not appear from the defendant’s showing in respect to the general art of dutches that there was involved the problem of locking a spindle securely without the possibility of minute disturbances of the adjustment of the spindle. In micrometer calipers• used for accurate measurement of parts and constructed to determine microscopic differences within y 1000 of an inch, the problem would seem to be oí a different nature from that ordinarily involved in applying a clutch. If therefore it could be fairly said that in general principle, and considered merely as clutches, the device of the patent in suit and that of Clapp were similar, rhere would still remain the question whether there was room for •itivemion in adapting a clutch operating upon this principle to the specific purpose of use in a delicate measuring instrument and to the improvement of micrometer calipers either in respect to the feature of locking the spindle without disturbance, or in respect to convenience of manu facture.

The patents of the prior art relating to micrometer calipers indicate dearly the need for locking means which shall prevent disturbance of the spindle. None of them shows the use in this specific branch of art of the split-ring with its tangential surface, roller, and actuating-ring. There is nothing in the Clapp patent to suggest that in this somewhat complicated structure is a form of clutch which is better adapted than other clutches for the secure locking of a micrometer spindle and for convenient assemblage with an acluating-ring and a micrometer frame.

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Related

Edna Brass Mfg. Co. v. Wiltbonco Mfg. Co.
300 F. 36 (First Circuit, 1924)
Brown & Sharpe Mfg. Co. v. L. S. Starrett Co.
225 F. 997 (D. Massachusetts, 1915)

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Bluebook (online)
225 F. 993, 1912 U.S. Dist. LEXIS 1857, Counsel Stack Legal Research, https://law.counselstack.com/opinion/brown-sharpe-mfg-co-v-l-s-starrett-co-mad-1912.