Grindle v. Welch

146 F. Supp. 44, 112 U.S.P.Q. (BNA) 15, 1956 U.S. Dist. LEXIS 2373
CourtDistrict Court, N.D. California
DecidedOctober 29, 1956
DocketCiv. A. No. 34531
StatusPublished
Cited by1 cases

This text of 146 F. Supp. 44 (Grindle v. Welch) is published on Counsel Stack Legal Research, covering District Court, N.D. California primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Grindle v. Welch, 146 F. Supp. 44, 112 U.S.P.Q. (BNA) 15, 1956 U.S. Dist. LEXIS 2373 (N.D. Cal. 1956).

Opinion

EDWARD P. MURPHY, District Judge.

This is a suit for the declaration of invalidity of a patent, No. 2,534,644, and for certain relief incident to the invalidation of that patent, including damages and the assignment of the patent to the claimed true inventor. Jurisdiction arises under 28 U.S.C. § 2201.

. The patent in question concerns a measuring device to determine the quantity of gasoline in the wing tanks of airplanes, known as a “dipstick.” The dipstick is a liquid fuel column gauge, of a type long familiar. A patent issued as long ago as May 26, 1863, to one Hyde (No. 38,681) for a “cask gauge” described the essentials of the gauge as being a tube or cylinder “made of transparent glass, or its equivalent, and left open at either end”, enclosed within the center of a square slitted rod “made of wood, metal, gutta-percha, or any other suitable material, so that either end of the rod shall be flush with the ends of the enclosed tube”, and with suitable gauging scales marked on the four sides of the enclosing rod, each adapted to a particular type of cask, so that by observing the level of the fluid in the central measuring tube, the content of the cask or vessel could be ascertained. The operation of the device is the same as that Used by children playing with straws. The tube is inserted vertically into the liquid to the bottom of the vessel. The operator then closes the top of the tube, éither with his finger, or with some sort of valve, and withdraws the tube. The atmospheric pressure on the lower end of the tube, as it is lifted from the liquid, retains the liquid in the tube (up to its point of specific gravity). Hyde in his 1863 patent said:

“It is evident that the height of the column of liquid thus confined in the tube will indicate the depth of its previous immersion in the body of the fluid, and by comparing this column with a properly-graduated scale the quantity of liquid in any given cask or vessel can be accurately ascertained almost at a glance.”

In 1922, another patent was issued to one Schmitt (No. 1,423,156) for essentially the same type of liquid fuel column gauge, differing only in the manner in which the central measuring tube is supported by the outer structure upon which the gradations are marked, and the slits in the outer structure through which the level of the liquid in the measuring tube may be observed.

This was the state of the prior art in liquid fuel column gauges. It is unneces[46]*46sary to speculate upon whether the devices described in the Hyde and Schmitt patents were ever sufficiently “inventive” within the meaning of the patent laws to be patentable.

In 1948 the plaintiff in the instant case, Grindle, an engineer employed by Pan American Airways, developed at the request of his employer a dipstick, or liquid fuel column gauge, which would render more satisfactory service than those then in use. Grindle developed, apparently without knowing of the Hyde and Schmitt patents, a stick which consisted essentially of several measuring tubes, rather than one, joined in a single assembly, and made of plastic. He then contacted the defendant, Welch, at that time a representative for a plasties products firm, and handed him detailed drawings and a mock-up sample of the stick he had designed, for the purpose of securing price quotations from the defendant’s employer. Defendant’s employer returned the plans with the report that the particular shapes of plastic required to accommodate the plaintiff’s design would be too costly to manufacture, and sent along several items of standard plastic tubing, called “extrusions”, to inquire of plaintiff whether they would be adaptable to his needs. After some experimentation and consideration of various alternative expedients, plaintiff Grindle devised a dipstick incorporating standard plastic extrusion parts. In all essentials, the dipstick as finally submitted by plaintiff Grindle to defendant Welch and the latter’s employer by means of a complete sketch and mock-up sample was the dipstick incorporated ultimately in Patent No. 2,534,644.

At the time of submission of the plans and mock-up of the dipstick to Welch, Grindle had no thought of patenting the stick, and no desire to keep the device secret for purposes of personal commercial exploitation or for any other purpose. He understood that because of the development work done by his employer, Pan American, through himself, the employer would receive a favorable purchase price quotation from the ultimate producer of - the stick, whether that producer was to be Welch’s employer or Welch himself. There was no disclosure by Grindle to Welch of any confidential nature which could lead to a recompensable breach of trust on the part of Welch.

It appears that during the period of final development of the dipstick, Welch had -formed the plan to set himself up in the dipstick manufacturing business. He did so, and commenced to supply dipsticks in conformity with the plans drawn by Grindle. There were two minor variations in the stick as delivered and the stick as designed, and these variations (consisting of the substitution of radial grooves for square cut grooves in the wooden filler which spaced the two plastic measuring tubes inside the over-all square plastic housing tube, and of the substitution of plastic cement fill for the solid end plugs which Grindle had originally designed to shut off the ends of the square housing tube) were accepted by Grindle for Pan American because they had no appreciable effect on the functioning of the dipstick as designed by Grindle. They were minor details of construction or manufacture, “bugs”, that every manufacturer encounters in the construction of his products, and that are eliminated by altering minor details which leave the product as a whole unaffected. The same is true for the protrusion of the tubes beyond the end pieces. Any skilled mechanic, or any person who has had some experience in working with plastics, could have accomplished the substitution of the cement mass for the end plugs, and the radial grooves for the square cut grooves, as well as the protrusion of the tubes beyond the end seals.

Welch commenced production of the sticks and made his first delivery to Pan American on August 12,1948. That date marked the beginning of public use of the dipstick. Grindle was soon thereafter assigned to other duties and took no further interest in the dipstick. Thereafter, on August 12, 1949, Welch filed for a patent on the dipstick, swearing that he was the true inventor. His patent [47]*47application contained three claims. Claim 1 was the dipstick as disclosed in Grindle’s drawing No. D-32.061.114, published on June 10, 1948. Claims 2 and 3 varied a few minor details of construction as, for example, using end plugs instead of a cement mass to seal the ends of the plastic housing tube through which the two measuring tubes protruded (the original Grindle drawing had provided for similar end plugs, and was changed to suit the production convenience of Welch), the protrusion of the tubes beyond the end pieces, and adding a nail as an additional means of securing the end plugs. None of the variations of Claims 2 and 3 from Claim 1 were substantial improvements. They were changes of a sort which any mechanic, in or out of the plastics field, might have devised in the course of construction. Essentially, all three claims were the same claim, namely a claim on the device substantially as pictured in the Grindle drawing of June 10,1948.

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Related

C. Martin Welch v. Eugene L. Grindle
251 F.2d 671 (Ninth Circuit, 1957)

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Bluebook (online)
146 F. Supp. 44, 112 U.S.P.Q. (BNA) 15, 1956 U.S. Dist. LEXIS 2373, Counsel Stack Legal Research, https://law.counselstack.com/opinion/grindle-v-welch-cand-1956.