Hitchcock v. American Plate Glass Co.

227 F. 227, 152 C.C.A. 17, 1915 U.S. App. LEXIS 2299
CourtCourt of Appeals for the Third Circuit
DecidedJuly 22, 1915
DocketNo. 1883
StatusPublished

This text of 227 F. 227 (Hitchcock v. American Plate Glass Co.) is published on Counsel Stack Legal Research, covering Court of Appeals for the Third Circuit primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Hitchcock v. American Plate Glass Co., 227 F. 227, 152 C.C.A. 17, 1915 U.S. App. LEXIS 2299 (3d Cir. 1915).

Opinion

BUFFINGTON, Circuit Judge.

In the court below Halbert K. Hitchcock filed a bill against the American Plate Glass Company and James W. Cruikshank, charging them with infringement of four patents, viz.: No. 934,442, granted September 21, 1909, for grinding apparatus; No. 934,612, of same date, for grinding apparatus; No-. 1,056,415, of March 18, 1913, for apparatus for applying abrasives to grinding apparatus; and No. 1,056,416, of same date, for method of applying' abrasives to grinding apparatus. On final hearing the court below, in an opinion reported at 216 Fed. 766, held the defendants did not infringe. From a decree dismissing his bill, Hitchcock appealed.

The case concerns grinding plate glass. Such glass is first cast in large rough sheets, after which such sheets are imbedded in plaster of paris on the table of a large grinding machine, and are ground smooth by the use of sand as an abrasive. Rough, coarse sand is used for the first stage of grinding, and sands of finer grades are successively used as the surface becomes more finished, until the glass is ready for polishing, which is done by the use of other materials not here involved. But not only is sand of different fineness required as the grinding process goes on, but such sand must be applied with such [228]*228volume of water as will, on the one hand, give the fluidity necessary to insure diffusion of the sand over the grinding table, but, on tire other hand, it is necessary to avoid such fluidity as will wash, the sand from the grinder. The present case involves a process and apparatus for mechanically separating the sand into the different grades of fineness required at successive grinding stages, and of feeding such grades in proper fluid condition to the grinding table as -such grades are needed. The grinding machines used by both parties are alike, and are not involved in the present case, further than that a general description of them is necessary to a proper understanding of the sand-selecting and sand-feeding devices used by the patentee and the alleged infringer.

As stated above, the cast glass sheets are placed on a large, circular, revoluble, grinding table, and are securely held in place by imbedding them in plaster of paris. Above the table is a cross-beam, from which depend large runners, on the underside of which are cast iron shoes or blocks, which rest loosely on the surface of the imbedded glass. When the table is rotated at high speed, and sand and water are thrown upon it, the runners are rotated frictionally by the table, and an abrasion sets in, which gradually grinds the glass to a smooth surface adapted for the subsequent operation of polishing. Prior to Hitchcock’s devices the practice was to shovel coarse, ungraded sand into a Y-shaped trough, which was above and inclined to the table. This sand was washed by a hose onto the table. A gutter surrounded the table, into which the sand and water, as the grinding proceeded, were carried by the rotation of the table. From this gutter the mixed water and sand ran into a trough in which were several cross-barriers, which, as the mixture passed, trapped the heavier and larger grains of passing sand, while the lighter grains passed onward. Such sand grading was not uniform. In the first grinding operation, called facing, ungraded, coarse sand was carried to the grinding table by simply turning on a hose. In the several subsequent operative stages clear water was -turned on the table, and the finer grades of sand were thrown on in handfuls by the operative. The expense, efficiency, and character of the product depended on the skill and care of the operatives. There was no product uniformity.

Beyond the first barrier in the trough was usually placed a second, which served to trap a second body of sand from the passing water. This was called “canal sand.” After the facing operation, which usually took an hour or more, was finished, the glass and runners were carefully drenched with clear water to remove all coarse sand, and then, while a stream of clear water continued to play on the glass, operatives threw handfuls of “canal sand” on the table. This use of proper quantities of canal sand constituted the second step of the process. Beyond the “canal sand” barrier, the trough from each individual grinding table led to a common trough, which received the currents of water and finer grains of sand from all the tables of the plant. This common trough led to what was called the “fine sand house.” This latter had a long, rectangular basin, or pair of basins, [229]*229communicating with the trough at one end and having an overflow at the other. This basin was divided by overflow barriers into several compartments of substantial length and about three feet deep. In these compartments the sand was caught in successively finer grades as the water passed over the barriers. These different grades were shoveled into separate bins and were used in successive smoothing operations, being thrown in handfuls upon the watered glass surface as in case of the “canal sand”; that is, after the “canal sand” operation was completed the tables and runners were again carefully drenched with clear water, after which the coarsest “sand house” sand was then thrown on for the first smoothing operation. After about 10 minutes the table and runners were again drenched, and the second grade of “sand bouse” sand was used. After about the same time the tables and runners were again washed off, and the finest grade of “sand house” sand was thrown on and used. This completed the sand-grinding operation. It will be observed that in this process the velocity of the water at the particular instant, and not alone the weight of a particular sand particle, determined whether such particle would or would not be carried over the barrier it was approaching; and it will further appear that the velocity of the water was affected by the amount of sand over which the water passed in the several compartments being deep or shallow. It will also be apparent that the presence of the finer grades of sand on the table during the facing operation was no help, and indeed a hindrance, to the effectiveness of the grinding sand. It is also apparent that, where coarse grains were carried over to the finer grades, such coarse grains might score and scratch the glass in the smoothing operations. In that regard the proof is:

“As the water containing sand in suspension passed through this ditch, the coarse grades would settle out in the first compartment, and the fine grades in the succeeding compartments. The settling, however, had a fatal defect; for, when the pits were empty to start with, there was a current of water arid sand 2% feet deep, while, when the pits were filled, there was a current of only about 4 inches flowing across the pits. This resulted in the first pit filling up much more rapidly than the succeeding- ones, and a great quantity of very fine sand and mud being entrapped in the first compartment.”

This defect was so serious that resort was had to a partial corrective, by use of what is called a “laxiavator.” The proof in that regard is:

“In order to partially overcome this difficulty, there was provided what is called a laxiavator. The sands were shoveled out of the pits in' the fine sand house into water contained in this laxiavator, whore they were thoroughly agitated, and the mixture was then allowed to settle for approximately eight or (on minutes. Then the water and sand above an opening in the side of the laxiavator was drawn off through the opening into a settling box, where the sand settled and the water was afterward removed.

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Related

Hitchcock v. American Plate Glass Co.
216 F. 766 (W.D. Pennsylvania, 1914)

Cite This Page — Counsel Stack

Bluebook (online)
227 F. 227, 152 C.C.A. 17, 1915 U.S. App. LEXIS 2299, Counsel Stack Legal Research, https://law.counselstack.com/opinion/hitchcock-v-american-plate-glass-co-ca3-1915.