Tilghman v. Morse

23 F. Cas. 1238, 9 Blatchf. 421, 5 Fish. Pat. Cas. 323, 1872 U.S. App. LEXIS 1479

This text of 23 F. Cas. 1238 (Tilghman v. Morse) is published on Counsel Stack Legal Research, covering U.S. Circuit Court for the District of Southern New York primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Tilghman v. Morse, 23 F. Cas. 1238, 9 Blatchf. 421, 5 Fish. Pat. Cas. 323, 1872 U.S. App. LEXIS 1479 (circtsdny 1872).

Opinion

BLATCHFORD, District Judge.

This is a motion for a provisional injunction, founded on letters patent granted to the plaintiff October 18th, 1870, for an “improvement in cutting and engraving stone, metal, glass, &c.” The specification says: “My invention consists in cutting, boring, grinding, dressing, pulverizing, and engraving stone, metal, glass, wood, and other hard or solid substances, by means of a stream of sand or grains- of quartz, or of other suitable material, artificially driven as projectiles rapidly against them by any suitable method of propulsion. The means of propelling the sand which I prefer is by a rapid jet or current of steam, air, water, or other suitable gaseous or liquid medium; but any direct propelling force may be used, as, for example, the blows of the blades of a rapidly revolving fan, or the centrifugal force of a revolving drum or tube, or any other suitable machine. The greater the pressure of the jet, the higher will be the velocity imparted to the grains of sand, and the more rapid and powerful their cutting effect upon the solid substance. At a high velocity of impact, the grains of sand will cut or wear away substances much harder than themselves. Corundum can thus be cut with quartz sand, and quartz rock can be cut or worn away by small grains or shot of lead. I have sometimes used iron sand, composed of small globules of cast iron. By the term sand, in this specification, I mean small grains or particles of any hard substance, of any degree of fineness, of which common quartz sand is a type. The hardest steel, chilled cast iron, or other metal, can be cut or ground by a rapidly-projected stream of quartz sand. Articles of cast or wrought metal may have their surfaces thus smoothed and cleaned, from slag, scale, or other incrustation. The surfaces of wrought stone in buildings or elsewhere can thus be cleaned and refreshed. By means of stencil plates, screens, or suitable covering substances, letters or designs can thus be cut or engraved upon hard substances. By varying the shape, number, and direction of the projected streams of sand, and by giving to them and to the articles treated suitable movements by means of lathes, planing, or drilling machines, or other known mechanical devices, cuts or holes may be made of any shape or size. When sand. of a brittle nature, such as quartz or emery, is very rapidly projected against a hard material, the grains are broken by the shock into fine powder, and the process may thus be used as a method of pulverisation. Where a jet of water under heavy pressure is used, as in hydraulic mining, the addition of sand will cause it to cut away hard and close-grained substances, upon which the water alone would have little or no effect. Pebbles or stones of size and weight as great as can be rapidly projected by the jet of water used will have a battering, penetrating, and dislocating effect, which will assist the disintegrating and scouring action- of the water. Heretofore, when sand has been used as a grinding or cutting material, it has been applied between solid substances, moved over each other under heavy pressure, so as to make a series of scratches, as in the ordinary cutting of stone and glass, or else in a solidified form, as in a grindstone or sandpaper, or sometimes in a semi-fluid state, as when a body is rubbed or moved in a mass of sand. The peculiar feature of my invention, which distinguishes it from other methods of cutting and grinding, is, that each grain of sand acts, by its own velocity and momentum, like a bullet or projectile, and pulverizes, cuts, or indents the object it strikes. From this peculiarity of action, it results, that some sub-. stances, which, though comparatively soft, are also tough, or malleable, or elastic, and not pulverizable by a blow, such as copper, lead, paper, wood, or caoutchouc, for example, are less rapidly cut and ground by the sand blast, particularly at moderate velocities, than some much harder substances which are brittle or pulverizable, such as stone, glass, or porcelain. Another peculiarity of the sand blast is, that the grinding or cutting action takes place upon irregular surfaces, cavities, corners, and recesses hardly [1240]*1240■accessible to ordinary methods. I believe that steam will generally be found the most convenient impelling jet, particularly for high velocities, but, in some localities, air or water may be cheaper.”

The specification then describes, with references to a drawing annexed, a method , of carrying the invention into effect, for cutting stone by means of quartz sand projected by a jet of steam. It then proceeds: “For purposes where only a small quantity, of material is to be cut or ground away from the surface of a hard substance, and where only a moderate velocity of the sand is required, I have found the current of air produced by the ordinary rotary fan to be convenient. I have used this method for grinding or de-polishing glass, china, or pottery, either on entire surfaces, or on surfaces partially covered and protected, so as to produce an engraving of letters, ornaments, or designs. In engraving designs, air is more convenient than steam as an impelling jet, in this respect, that the sand keeps dry and rebounds, leaving the pattern clear, while with steam the sand becomes damp, and is apt to adhere to and clog the fine lines and corners. The sand, being fed into the fan, is carried along, by the currents of air, in a tube or close trank, and strikes upon the glass, which is held or moved opposite the mouth of the trunk, and cuts, grinds, or stars its surface. One arrangement, which I have found convenient for fiat glass, is, to cause the air current from the fan to descend in a narrow vertical tube of a cross section about three feet long by one inch wide, into the top of which the sand is evenly introduced by numerous small pipes, at the rate of about twenty cubic inches per minute for each square inch of cross section. A travelling apron carries the sheets of glass gradually and regularly beneath the sand blast, at about one inch distance. The finer the sand used, and the less the pressure of the blast, the finer is the grain of the depolished surface. Also, the finer the sand used, the more weak and delicate may be the texture of the covering substance used to produce the design. Good results have been obtained with designs cut in a layer of wax, and with paper or lace pressed close to the glass, and using sand which passed through a sieve of fifty wires per inch, and an air blast of the pressure of about one inch of water. With sand reduced to very fine powder, and an air blast of a pressure of eight or ten inches of water, a very delicate depolishing of the surface of glass has been produced. Numerous processes are known and used in the arts for producing, painting, or transferring designs on surfaces. Any of these processes by which a design can be produced or transferred in a sufficiently tough and resistant medium, may be used to prepare a surface for being engraved by the sand blast. Many natural objects, such as plants, leaves, insects, &c., which can be fastened flat upon a surface, have sufficient strength and resistance to a blast of fine sand to admit of their outline being thus engraved. Glass colored by a thin stratum of colored glass on one surface, may be ornamented by designs cut or ground through its colored stratum. Designs engraved by the sand blast to a sufficient depth, either in relief or intaglio, on a smooth surface, slate or glass, for example, can be reproduced by known processes of printing. "When the sand blast, at moderate velocities, is directed upon a metallic surface, it removes but little of the metal, but the grains of sand make innumerable small indentations of the surface, and produce a frosted, dull mat or dead appearance.

Free access — add to your briefcase to read the full text and ask questions with AI

Related

Hartell v. Tilghman
99 U.S. 547 (Supreme Court, 1879)

Cite This Page — Counsel Stack

Bluebook (online)
23 F. Cas. 1238, 9 Blatchf. 421, 5 Fish. Pat. Cas. 323, 1872 U.S. App. LEXIS 1479, Counsel Stack Legal Research, https://law.counselstack.com/opinion/tilghman-v-morse-circtsdny-1872.