Spee-Flo Manufacturing Corp. v. Gray Co.

237 F. Supp. 616, 144 U.S.P.Q. (BNA) 216, 1964 U.S. Dist. LEXIS 9126
CourtDistrict Court, S.D. Texas
DecidedOctober 14, 1964
DocketCiv. A. No. 14247
StatusPublished
Cited by5 cases

This text of 237 F. Supp. 616 (Spee-Flo Manufacturing Corp. v. Gray Co.) is published on Counsel Stack Legal Research, covering District Court, S.D. Texas primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Spee-Flo Manufacturing Corp. v. Gray Co., 237 F. Supp. 616, 144 U.S.P.Q. (BNA) 216, 1964 U.S. Dist. LEXIS 9126 (S.D. Tex. 1964).

Opinion

CONNALLY, Chief Judge.

STATEMENT OF THE CASE

The plaintiff, a Texas corporation, seeks to recover for the alleged infringement of U. S. Letter Patent No. 3,000,576 for a “spray gun” for the airless spraying of paints and other liquid finishing materials, granted September 19, 1961, to Gustave S. Levey and Stanton F. Harvey, of which plaintiff is now the owner. The defendant is a Minnesota corporation with an established place of business within this District and Division. It has sold a number of its so-called “FF” (meaning fine finish) tips for use in its own spray guns and with guns of other manufacture. This is alleged to constitute the infringement.

To understand the contribution to the art which the plaintiff contends has been made by the patent in suit, some explanation and history of the use of spray painting is necessary. Spray painting has long been known and used in the application of paints, varnishes, lacquer and other finishing materials. Spray painting has been and is now done either with or without the use of compressed air. Where compressed air is used (referred to during the trial, and hereafter, as “air-spray painting” or with the “air-guns”), paint is delivered to the gun at a relatively low pressure, from a “pressure pot”, and a jet of compressed air is impinged against the stream of paint to atomize it, or break it up into a mist, and to propel it toward the surface to be painted. It is desirable in all such cases to apply the paint in a strip or [618]*618swath of uniform texture, except at the edges. A “feathered” edge is desired, so that on succeeding passes an overlap may be made, and a complete covering of uniform thickness produced. A number of factors may affect the end result, such as the pressure at which the paint is supplied, its viscosity, flow rate, temperature, etc. It is without dispute in the evidence, however, that a skillful operator could produce a highly satisfactory result with the air spray gun; and until recently, practically all fine finishing (furniture, radio and television cabinets, pianos, appliances, etc.) was done by this means.

This air spray application, however, was attendant with certain highly unsatisfactory side results. When the paint, propelled by the stream of compressed air, struck the surface to which the finish was being applied, the paint-saturated air stream was deflected. This “over-spray” caused a waste of a substantial part of the finishing material being used, and additionally created a cloud of air, saturated with particles of paint, lacquer, solvents or other such materials. To protect the operator from breathing such air, it was necessary that the air in the work area be circulated constantly. Thus blowers, exhaust fans, filters and other such means were necessary.

By reason of these disadvantages of the air spraying, for a number of years airless spraying has received increasing favor in the industry. Airless paint spraying systems were offered for sale by the plaintiff, the defendant and a number of other companies in the field. In the airless spraying, an attempt was made to atomize and distribute the paint evenly by forcing it under high pressure through a small oval-shaped, sharp-edged nozzle opening. Much higher pump pressures were required. This airless method eliminated the disadvantages mentioned above which were attendant upon the air spray system, but the quality of the work was not as good. It appeared to be difficult, if not impossible, consistently to achieve a proper pattern or spray fan with the airless method, and the results in general were not satisfactory for fine finishing. The airless method was used extensively where fine finishing was not essential. Air spray was used almost exclusively where fine finishing was essential.

The invention in suit made it possible to eliminate the irregularities in the application of paint and other finishing material by an airless gun, whereby a result equally as desirable as that achieved with the air spray equipment might be attained. The disadvantages of the air spray system were eliminated. Witnesses in charge of finishing for Storkline (furniture), Eisen Bros, (furniture), Admiral (television and radio cabinets), Wurlitzer (organs), and Chris Craft (boats), in testifying on plaintiff’s behalf, have expressed great satisfaction with plaintiff’s new airless gun, and have stated that with the use thereof, a saving of approximately 20% in the materials to be applied has been accomplished, and that the same fine finish has been achieved as previously was available only with air spray.

THE INVENTION AND THE PATENT

In all airless spray painting with guns of the general type here involved, the paint is pumped at high pressure (in the range of perhaps 500 to 1500 pounds per square inch) through a hose, and is introduced into the gun through a valve, which may be opened and closed by the operator with a trigger-like device. The paint passes through the valve orifice, through a passage in the gun, and thence to the nozzle or spray tip. The nozzle orifice or spray orifice is a small elliptical shaped hole through which the paint passes, where it is hydraulically atomized by reason of the reduction to atmospheric pressure.

Through an accidental discovery in late 1959 by Levey and Harvey, who were working with plaintiff’s engineer Murdoch in attempting to improve the spray pattern, it was learned that a decrease in the pressure in the chamber between [619]*619the valve and the spray nozzle resulted in a much-improved pattern. After further experimentation, two methods of accomplishing this result were perceived, one form of which was commercialized by plaintiff in offering on the market its airless “H-gun” (for Harvey, one of the inventors) in December 1959.

The contribution of the patent in suit is the placing of a disc, with a center hole of a particular size (or, more accurately, in a particular ratio to the cross-sectional area of the spray orifice) between the valve and the spray orifice. This disc, with center hole, was referred to throughout the trial, and here, as the “preorifice”. It should be emphasized at this point that the use of a pre-orifice in approximately the same position as shown by the patent in suit, in itself, is not new. But in general, such earlier preorifice devices were much larger in cross-sectional area than the spray orifice. The real contribution of the invention was ascertainment and recognition of the fact that if the pre-orifice is reduced in size to approximately the same as the spray orifice, that the improvement in the spray pattern is accomplished. In brief, this is explained by the patent and by the plaintiff’s expert testimony at the trial, as follows. With the pre-orifice much larger than the spray orifice (as in prepatent guns), the paint reached the nozzle or spray orifice under high pressure and with low velocity. It was accelerated in the nozzle opening to the high velocity and low pressure of the spray fan. This resulted in the formation of a vena contracta which was in large part responsible for the imperfect spray patterns resulting. When the pre-orifice was reduced to the same size as the nozzle orifice (as in one of the two preferred embodiments of the patent in suit), the paint moved through the pre-orifice, and into the small chamber anterior to the spray orifice, under a reduced pressure, but with increased velocity, and in the form of a submerged jet; and traveled through said chamber as a submerged jet until reaching the spray orifice.

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Bluebook (online)
237 F. Supp. 616, 144 U.S.P.Q. (BNA) 216, 1964 U.S. Dist. LEXIS 9126, Counsel Stack Legal Research, https://law.counselstack.com/opinion/spee-flo-manufacturing-corp-v-gray-co-txsd-1964.