Wilkinson v. Ladd

234 F. Supp. 273, 143 U.S.P.Q. (BNA) 132, 1964 U.S. Dist. LEXIS 9566
CourtDistrict Court, District of Columbia
DecidedOctober 16, 1964
DocketNo. C.A. 1002-63
StatusPublished
Cited by1 cases

This text of 234 F. Supp. 273 (Wilkinson v. Ladd) is published on Counsel Stack Legal Research, covering District Court, District of Columbia primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Wilkinson v. Ladd, 234 F. Supp. 273, 143 U.S.P.Q. (BNA) 132, 1964 U.S. Dist. LEXIS 9566 (D.D.C. 1964).

Opinion

JACKSON, District Judge.

This is a civil action pursuant to 35 U.S.C. § 145 seeking judgment of this Court authorizing the defendant, Commissioner of Patents, to issue Letters Patent of the United States containing claims 21 through 27 of an application Serial No. 800,271, entitled “Oil Filter”, filed March 18, 1959, by plaintiff, James W. Wilkinson and assigned to plaintiff, Hastings Manufacturing Company.

The invention described in the application relates to oil filter assemblies for automobile engines. Each assembly consists of an upright casing mounted on or near the engine, a sealed cover, a cylindrical filter cartridge of the disposable or throw-away type, and a spring-biased pressure relief valve affording a by-pass for the oil in the event the cartridge becomes clogged. The valve unit forms part of the disposable cartridge and is located at one end of an axial opening through the center of the cartridge. The valve is constructed like an annular disk so that it may accommodate an oil delivery tube around which the cartridge is mounted.

Claims 21 and 26 are representative of the two forms of plaintiffs’ invention. In claim 21 the valve is placed at the upper end of the cartridge; in claim 26 it is placed at the lower end. The claims read as follows:

“Claim 21:
“In a filter for a pressure circulated medium, the combination of a casing including a bottom having an inlet opening and a discharge opening therein, an inlet tube mounted on said casing bottom in communication with said inlet opening thereof and discharging at the outer end of said casing, a filter cartridge supportedly seated on said bottom and surrounding and removably associated with said inlet tube and comprising inner and outer and top and bottom walls, the inner and outer walls being foraminate, said cartridge containing a compacted fibrous filtering medium, there being a discharge passage between said inlet tube and said inner cartridge wall opening to said discharge passage in said casing, said inlet tube projecting above and discharging into said casing above said cartridge, and a pressure relief valve comprising a valve casing supposedly mounted on the upper end of said cartridge and having a downwardly projecting portion projecting into and retainingly engaged with the upper end of said inner cartridge wall, said valve casing including an inwardly facing valve seat having an inlet opening to said casing and discharging into said discharge passage, an annular disk valve disposed in said valve casing in coaeting relation to said valve seat, and a coil spring supposedly disposed within said valve casing in coacting relation to said valve and tensioned to hold said valve on its seat only under such pressure as is required for passing a substantial portion of circulated medium through the filtering material within the cartridge.
“Claim 26:
“In a filter for a pressure circulated medium, the combination of a casing including a bottom having an inlet opening and a discharge opening therein and having an upwardly^ facing cartridge seat surrounding said openings, an inlet tube mounted on said casing bottom in communication with said inlet tube thereof and discharging at the outer end of said casing, a filter cartridge containing a compressed fibrous filtering medium supportedly seated on said bottom and removably associated with said inlet tube and comprising end walls and inner and outer foraminate walls, there being a discharge passage between said inner cartridge wall and said inlet tube, a valve casing disposed at and fixedly connected to said inner car[275]*275tridge wall at its lower end, a valve seat member disposed within said valve casing and having inlet openings therein, a tubular discharge member for said valve casing disposed through said valve seat and seated upon said cartridge seat on said bottom to discharge into said discharging opening of said casing bottom, a valve disposed within said valve casing in coacting relation to said valve seat thereof, and a coil spring supposedly disposed within said valve casing in coacting relation to said valve and tensioned to hold the valve on its seat under predetermined pressure required for passing of the circulated medium through the filtering material within the cartridge.”

Those claims were rejected by the Patent Office on the ground that their subject matter would have been cbvious at the time the invention was made to a person having ordinary skill in the art to which the subject matter pertains. 35 U.S.C. § 103. In support of this rejection the Patent Office cited United States Patents to Kovacs, et al., No. 2,533,266, Vokes, No. 2,598,322 and Wilkinson, No. 2,855,103. At trial the Patent Office introduced additional patents to Aldham, No. 2,221,465, and Boewe, et al., No. 2,955,249.

The Kovacs et al. patent (1950) shows in Figure 5 an oil filter assembly similar to plaintiffs’ first species, where the relief valve is disposed at the top of the filter cartridge so as to be remote from the point at which oil leaves the filter casing. The relief valve itself is in the form of a spring biased sleeve, and covers radial ports in a tube which surround the central oil delivery tube (or standpipe). The space between the tube and and the standpipe defines the exit through which oil passes down and out of the casing, the tube having other lateral ports through which the filtered oil normally flows after passing radially through the cartridge. The valve assembly of Kovacs et al. forms part of the cover for the casing, and is not thrown away with a spent cartridge.

The patent to Vokes, granted in 1952, shows an inner cartridge and relief valve arrangement similar to plaintiffs’ second species, in the sense that the relief valve is near the point at which fluid leaves the casing. Vokes’ relief valve is an annular disk held against fluid ports by a spring.

The patent to Wilkinson, granted in 1958, is plaintiffs’ own patent and shows a filter assembly similar to the first species of their application here, except that no relief valve is included.

The Aldham patent, granted in 1940, discloses a disposable oil filter cartridge having a built-in pressure relief valve in its crown. One of its objects was said to be the provision of a by-pass means in the cartridge which may be removed and replenished each time the cartridge is changed, thus tending to prevent failure of the by-pass apparatus by reason of fatigue of the spring. Although Aldham delivers oil at the side of his casing, rather than up through a standpipe as in plaintiffs’ assemblies, the filtering method is basically the same.

The Boewe et al. patent (1961) reveals a disposable cartridge having an annular disk relief valve directly incorporated within it. In discussing the removal of the cartridge, the Boewe patentees state that “(t)he old bypass valve is discarded with the cartridge”.

At trial it was shown by plaintiffs that certain structural details of their valve and cartridge filter combination were not anywhere disclosed in the patents relied upon by the defendant Patent Office. In response to this showing, the defendant contended these structural details would have been obvious to persons skilled in the art. (35 U.S.C. § 103).

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Bluebook (online)
234 F. Supp. 273, 143 U.S.P.Q. (BNA) 132, 1964 U.S. Dist. LEXIS 9566, Counsel Stack Legal Research, https://law.counselstack.com/opinion/wilkinson-v-ladd-dcd-1964.