Zenith Controls, Inc. v. Automatic Switch Co.

648 F. Supp. 1497, 2 U.S.P.Q. 2d (BNA) 1025, 1986 U.S. Dist. LEXIS 16857
CourtDistrict Court, N.D. Illinois
DecidedDecember 5, 1986
Docket84 C 9477
StatusPublished
Cited by3 cases

This text of 648 F. Supp. 1497 (Zenith Controls, Inc. v. Automatic Switch Co.) is published on Counsel Stack Legal Research, covering District Court, N.D. Illinois primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Zenith Controls, Inc. v. Automatic Switch Co., 648 F. Supp. 1497, 2 U.S.P.Q. 2d (BNA) 1025, 1986 U.S. Dist. LEXIS 16857 (N.D. Ill. 1986).

Opinion

MEMORANDUM OPINION AND ORDER

BRIAN BARNETT DUFF, District Judge.

Plaintiff Zenith Controls, Inc. (“Zenith”) seeks a declaratory judgment that U.S. Patent No. 4,157,461 (“the ’461 patent”), owned by defendant Automatic Switch Company (“ASCO”), is invalid and unenforceable and is not infringed by the manufacture, use, and sale of certain Zenith products. Zenith also accuses ASCO of violating § 2 of the Sherman Act, 15 U.S.C. § 2, by attempting to enforce a patent which it knows to be invalid and unenforceable. ASCO counterclaims for patent infringement. The case comes before the court on Zenith’s motion for partial summary judgment as to the unenforceability and invalidity of the ’461 patent. 1

I. BACKGROUND

ASCO’s ’461 patent, issued in 1979 to Dominick Wiktor, covers an arrangement of electrical switches for use in industrial and commercial power distribution systems. The patent’s design incorporates the functions of three kinds of previously known switches: automatic transfer switches, bypass switches, and isolation switches.

An automatic transfer switch (“ATS”) ensures an uninterrupted supply of power to a particular user or “load” by sensing a failure of the normal power source and automatically switching the load to a backup power source, such as an emergency generator. A bypass switch (“BPS”) routes current around a segment of an electrical circuit so that although the bypassed portion remains in the circuit, its presence is no longer essential. In this sense a BPS resembles a bypass around a portion of a highway; the bypass permits traffic to move toward its destination along either of two routes, enabling workers to close the main road for repairs without cutting off the flow of traffic.

An isolation switch (“IS”) disconnects a component from a circuit and thus prevents current from reaching it — much as erecting a roadblock on a main road forces traffic onto a bypass and isolates the main road for repairs. In their most rudimentary form, isolation switches are simply plugs connecting one part of an electric circuit to another, such as the plugs that connect household appliances to wall sockets, or the jacks that connect headphones to stereo receivers. Light switches and circuit breakers are slightly more complicated types of isolation switches.

Automatic transfer switches, bypass switches, and isolation switches long have been used in combination. For many *1500 years, workers servicing or replacing an ATS first bypassed it with a BPS so that its isolation would not disrupt the flow of electricity to the load, then isolated or removed it from the circuit with an IS to allow handling of the ATS without risk of electrical shock.

Although an arrangement consisting of an ATS, a BPS, and an IS permitted isolation and servicing of the ATS, it also posed two sorts of risks. First, if a worker failed to follow the proper sequence in disconnecting the ATS and attempted to isolate it from the circuit before bypassing it, he would cut off the flow of electricity to the load. Moreover, because the isolation contacts used to disconnect automatic transfer switches ordinarily are not designed to break high voltage circuits, disconnecting an ATS without first bypassing it could cause arcing that would endanger workers and equipment.

Second, in bypassing the ATS a worker might mistakenly connect the load to a source of power other than the power source to which the ATS then connected the load. If, for example, the ATS connected the load to an emergency power supply because the commercial power system had failed, a worker who bypassed the ATS by connecting the load to the failed commercial system, then disconnected the ATS, would cut off power to the load and risk arcing as he separated the ATS from the circuit. Alternatively, if the load were connected to the commercial power supply through the ATS and a worker bypassed the ATS by connecting the load directly to the emergency source, then for at least an instant the load would be connected simultaneously to both sources. The excessive voltage could cause an explosion injuring bystanders and damaging the system’s components.

In order to minimize these dangers, manufacturers of ATS, BPS, and IS arrangements developed “sequencing interlocks” to prevent workers from isolating automatic transfer switches before bypassing them, and “wrong source interlocks” to prevent workers from bypassing automatic transfer switches to a wrong source. Like the use in combination of automatic transfer switches, bypass' switches, and isolation switches, the use of sequencing interlocks and wrong source interlocks with such switch arrangements was known before Wiktor applied for the ’461 patent.

In addition to allowing the dangers ultimately eliminated by the use of sequencing and wrong source interlocks, the ATS-BPS-IS combination had another drawback: the three switches were separate components which had to be interconnected by cables. This required considerable floor and wall space and involved numerous moving parts associated with each set of switch contacts. The cables themselves were expensive and required maintenance. Moreover, each cable connection generated heat.

Wiktor partially solved these problems in the early 1970s by inventing a combined bypass and isolation switch (“BPIS”) eliminating the need for cables between the BPS and IS and reducing the number of moving parts. Wiktor received U.S. Patent No. 3,697,709 (“the ’709 patent”) for this invention in 1972, and soon afterwards ASCO began marketing its Series 932 BPIS under protection of that patent. ASCO’s Series 932 bypass isolation switches included both wrong source interlocks and sequencing interlocks, and were sold as accessories to automatic transfer switches. Because the Series 932 BPIS did not incorporate an ATS, however, it remained necessary to connect the ATS and BPIS with cables.

The ’461 patent improves on this arrangement by placing an ATS and a BPS in a single housing in such a way that the ATS moves bodily toward and away from the BPS upon operation of a lever. The two switches carry cooperable contacts which plug into one another when the two switches are together, much as an electrical plug slides into a wall socket, and separate when the lever pushes the ATS away. This arrangement eliminates the need for connecting cables and shrinks the amount of space required for the switch assembly. Additionally, because operating the lever to *1501 push the ATS away from the BPS isolates the ATS from the circuit, there is no need for a separate IS or for the pivoting isolation contacts present in a BPIS. As a result, the ’461 design requires fewer moving parts than previous switch arrangements. A sequencing interlock prevents disconnection of the ATS before it has been bypassed, and a wrong source interlock prevents bypassing the ATS to the wrong source.

Zenith challenges the '461 patent on two grounds. First, it argues that the entire patent is unenforceable as a matter of law because ASCO engaged in inequitable conduct before the Patent and Trademark Office (“PTO”) in procuring Claim 11 of the patent. Zenith alleges that ASCO concealed from the PTO the fact that ASCO’s Series 932 BPIS contained each of the three elements of Claim 11.

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648 F. Supp. 1497, 2 U.S.P.Q. 2d (BNA) 1025, 1986 U.S. Dist. LEXIS 16857, Counsel Stack Legal Research, https://law.counselstack.com/opinion/zenith-controls-inc-v-automatic-switch-co-ilnd-1986.