Packwood v. Briggs & Stratton Corp.

99 F. Supp. 803, 90 U.S.P.Q. (BNA) 335, 1951 U.S. Dist. LEXIS 4196
CourtDistrict Court, D. Delaware
DecidedAugust 10, 1951
DocketCiv. A. 1307
StatusPublished
Cited by8 cases

This text of 99 F. Supp. 803 (Packwood v. Briggs & Stratton Corp.) is published on Counsel Stack Legal Research, covering District Court, D. Delaware primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Packwood v. Briggs & Stratton Corp., 99 F. Supp. 803, 90 U.S.P.Q. (BNA) 335, 1951 U.S. Dist. LEXIS 4196 (D. Del. 1951).

Opinion

LEAHY, Chief Judge.

Plaintiff sued for infringement Briggs & Stratton Corporation, an engine manufacturer, and Savage Arms Corporation, a manufacturer of power lawn mowers, upon claims 1, 2, 3 and 4 of reissue patent No. 23,146. The case was tried by jury. They returned a verdict of validity, infringement and awarded damages. . Defendants now move, under F.R. 50(b) 1 to have the verdict and judgment set aside and to have judgment in defendants’ favor in accordance with their former motion, made at trial (which was denied), for a directed verdict; or, in the alternative, for, under F.R. 59(a), a new trial. In addition, defendants have a motion' for summary judgment on their counterclaim. Plaintiff moves for an allowance of attorney’s fees and also for an increase in the amount of the verdict, under 35 U.S.C.A. §67.

According to plaintiff, the invention of the patent in suit is “an improvement in power lawn mowers; more accurately, perhaps, in air-cooled internal combustion engines for use in power lawn mowers.” 2 Such an engine, whether used on a lawn mower or for any of the numerous other purposes for which it may be employed, ordinarily has an impeller or fan mounted on its crankshaft to blow cooling air across the cylinder and a hoodlike shroud or blower housing which partially surrounds the engine and directs the stream of cooling air from the fan across the cylinder. The fan is inside the housing, in line with an opening at one side through which the cooling air is drawn. Defendant Briggs & Stratton for many years has manufactured engines having a stationary coarse-mesh wire screen fixed across the air intake opening in the housing and is still doing so. 3 This construction is, by stipulation, prior art as to the patent in suit. 4 The purpose of the screen is to intercept grass and debris which might be carried into the housing by the air stream.

In the plaintiff-Packwood patent a similar screen is used, but it is fastened to the engine starter pulley instead of the blower housing; but otherwise there is no change in any part of the engine or *805 lawn mower. This difference in fastening of the screen, plaintiff’s counsel admits, is the “invention”. 5

Whether the air intake screen is, stationary (fixed to the housing) or rotary (secured to the starter pulley) its function is admittedly the same — it permits cooling air to enter the blower housing and at the same time excludes debris or foreign matter therefrom. 6 The claimed advantage of the rotating screen over the fixed screen is that grass and debris drawn against the rotary screen by the suction of the impeller 'will be “flicked outward” by centrifugal force so as not to be drawn into the blower housing by the stream of cooling air. 7 In practice, the evidence suggested the rotating screen has, at best, only a slight advantage over the fixed screen; indeed, it is uncontradicted in the record some officials of Briggs & Stratton can see no advantage in it whatsoever, 8 and when a rotating screen is used both the screen and the interior of the blower housing can become clogged with grass under certain conditions. 9

Plaintiff admitted, through his patent expert and through counsel, it is old to use a rotating screen at the entrance to a blower housing to intercept dirt and debris which tend to be drawn into the housing by an impeller and to throw them off centrifugally 10 — at least half a century old. 11

Defendants rely primarily upon Knight, No. 1,789,871, to sustain their defense the patent in suit is anticipated. Plaintiff’s expert admitted 12 the problem to which the Knight patent is addressed is identical with Packwood as well as that of the defendant Briggs & Stratton engine with the fixed screen.

Evidence shows McCulloch Motors Corp. and Whirlwind Mower Co. had begun to produce engines and power mowers incorporating the rotating screen, and defendant Briggs & Stratton had received a production model of an engine equipped with a rotating screen — all before Packwood disclosed his alleged invention to any of these three concerns. 13 Three witnesses skilled in the’ field of internal combustion engines for power mowers, and who were actively employed in that field, testified without contradiction when the rotating screen first came to their attention — before' Packwood “disclosed” it to them — they recognized it as old and “elementary” and could see nothing patentable in it. 14 One of these three men, a completely disinterested witness, had in fact conceived the idea independently of Packwood and did not consider it inventive. 15 It is uncontradicted engines with rotating screens are articles of general utility, employed for a wide variety of purposes 16 and defendant Briggs & Stratton has no way of knowing after it sells its product what any particular engine will be used for. 17

After trial on the merits the jury returned a verdict finding the patent in suit valid and infringed by both defendants “as to lawn mowers only”. 18 The jury found a reasonable royalty, as to each defendant, is 21/2 cents per unit, and assessed damages against defendant Briggs & Stratton on the basis of 295,730 units and against Savage on the basis of 29,036 units. 19

In support of the motions, defendants argue the patent in suit does not constitute invention because (1) it cannot constitute invention to choose which of two closely adjacent parts should be used to mount the air intake screen of an internal combustion engine used on a lawn mower; (2) it does not constitute invention to transpose an old device or expedient from *806 one art to another closely analogous art, where that device or expedient plays the same role in both cases; (3) the introductory phrase of a claim, which merely defines the environment in which a structure is used, cannot patentably distinguish the claimed combination from an identical prior art combination; and (4) the Commissioner of Patents is not justified in reissuing a patent where the patentee makes only a bald statement in the reissue oath that the defects in the original patent occurred through inadvertence, accident or mistake, — without specifying which — and merely points out the need for the reissue without explaining how the defect arose which necessitated it.

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Bluebook (online)
99 F. Supp. 803, 90 U.S.P.Q. (BNA) 335, 1951 U.S. Dist. LEXIS 4196, Counsel Stack Legal Research, https://law.counselstack.com/opinion/packwood-v-briggs-stratton-corp-ded-1951.