Allen-Bradley Co. v. Square D. Co., 9017

• Decision Date: 29 June 1948
• Docket Number: No. 9017,9018.,9017
• Citation: 168 F.2d 334
• Parties: ALLEN-BRADLEY CO. v. SQUARE D. CO. (two cases).
• Court: U.S. Court of Appeals — Seventh Circuit

168 F.2d 334 (1948)

ALLEN-BRADLEY CO. v. SQUARE D. CO. (two cases).

Nos. 9017, 9018.

Circuit Court of Appeals, Seventh Circuit.

March 6, 1948.

Rehearing Denied June 29, 1948.

Edwin B. H. Tower, Jr., of Milwaukee, Wis., and Carlton Hill and Samuel W. Kipnis, both of Chicago, Ill. (Victor Beam, of New York City, of counsel) for Allen-Bradley Co.

J. Bernhard Thiess, Sidney Neuman and M. Hudson Rathburn, all of Chicago, Ill. (Myron J. Seibold, of Detroit, Mich., of counsel), for Square D Co.

Before MAJOR and KERNER, Circuit Judges, and LINDLEY, District Judge.

MAJOR, Circuit Judge.

These appeals are from a judgment, entered August 15, 1945, in a patent infringement suit. In appeal No. 9017, plaintiff appeals from that part of the judgment dismissing its complaint, while in No. 9018, defendant cross-appeals from that part of the judgment in dismissing its counterclaim.

The plaintiff Allen-Bradley Company on June 3, 1938 filed its complaint charging infringement of Letters Patent No. 2,071,149 (subsequently referred to as patent 149), issued August 17, 1937, upon an application filed July 11, 1935, which contained thirty-one claims, only seven of which are involved in this suit, and upon Wilms and Petersen Reissue Patent No. 20,676, issued March 22, 1938, upon an application filed February 9, 1938, containing six claims, only one of which is now relied upon. The District Court held these claims of both patents invalid, and it is from this holding that Allen-Bradley appeals in No. 9017.

The defendant Square D Company, on March 30, 1939, filed a counterclaim charging plaintiff with infringement of claims 31 to 36, inclusive, of its Jackson Patent No. 2,143,697, issued January 10, 1939, upon an application filed December 27, 1934. The defendant, also, on January 27, 1941, filed another counterclaim charging infringement of its Van Valkenburg Patent No. 1,890,009, issued December 6, 1932, upon an application filed August 11, 1930. Both of these counterclaims were dismissed on the ground of noninfringement, without any holding as to validity. The defendant appeals in No. 9018 from the judgment dismissing the counterclaim on the Jackson Patent. No appeal has been taken from the judgment dismissing the counterclaim on the Van Valkenburg Patent.

All of the patents in suit are concerned with electric switches employed in the starting of alternating current motors. The trial below was concerned primarily with the question of the validity of plaintiff's patent '149, and most of the attack here is upon the court's finding of invalidity. Plaintiff's reissue patent apparently was considered of minor importance in the court below, as it is here.

We shall first consider plaintiff's appeal (No. 9017) from the judgment holding invalid Patent No. '149 and Reissue Patent No. 20,676. Patent No. '149 discloses a mechanical structure designed to open a circuit and interrupt an electrical current. Its object, so we are informed, was to provide a switch that would have larger capacity than a switch in which the arcs were dispersed in an open hood, as in the prior art. The object allegedly was obtained by impounding the arcs between double-break movable and stationary contacts and actuating the movable contacts by a contact carrier arranged outside the closed hood and having a contact holder passing through an opening into the hood.

The switch is shown in the patent drawing as connected in circuit to start and stop an alternating current motor operated on a three-phase alternating supply circuit. The three-phase current rises and falls between zero current during each half-cycle and reverses its direction at the end of every half-cycle in passing through zero.

The switch is provided with three poles, one for each phase, in each of which are double-break contacts, stationary contacts and movable contacts, to make and break the circuit between the motor and the supply circuit. The stationary contacts are spaced apart and arranged on terminals connected to the supply circuit. The movable contacts are arranged on a bridge bar carried by a resilient contact holder mounted on a reciprocable contact carrier operated by a magnet and gravity. The double-break movable and stationary contacts in each pole are enclosed in a closed hood, called an arc enclosing chamber in the patent, and are arranged between the terminals to form a magnetic loop by which is created a magnetic field to impound the arcs in the ends of the hood.

The contact holder is provided with a post attached at its bottom to the contact carrier and having stop lugs at its top. The bridge bar is arranged on the post and urged against the stop lugs by a spring interposed between the bridge bar and the cross-bar carrier. The spring is enclosed in a spring shield having a clearance in the opening to leave it free from the hood. The spring shield has to be free in the opening, or otherwise the post would slide through the shield and bridge bar on raising the contact carrier, and the movable contacts would not be raised to engage the stationary contacts.

This switch, so it is stated, operates on a different principle from the prior art in that the magnetic loop impounds the arcs in the ends of the closed hood and the contact holder has free sliding motion in the opening into the closed hood to actuate the movable contacts. There are seven claims of this patent in suit, which may be roughly divided into two classes. Claims 21, 22, 23, 24 and 26 relate to the combination by which the arcs are impounded in the ends of the closed hood while the contact holder has free sliding motion in the opening to actuate the movable contacts. Claim 21, which appears to be typical of this group of claims, has been arranged by plaintiff with its essential elements shown in italics. It is as follows:

"In an electric switch for industrial control service,

"(1) two spaced stationary contacts (8)

"(2) a bar (34) movable with substantially a translating motion toward and from the contacts to electrically bridge the same,

"(3) conductors (51) leading to the contacts from a direction opposite to the approach of the bar,

"(4) an arc-enclosing chamber (37) enclosing said contacts and bar (34), said chamber having but a single opening leading thereto,

"(5) a carrier assembly (20) for moving the bar to and from the contacts and having a part (25) movable through said opening and substantially closing the same, the internal dimensions of the enclosure being such that its walls lie closely adjacent to the contacts and bar, and the clearance between said part which moves through the opening and the walls of the opening being sufficient to facilitate the escape of accumulating gases from within the chamber but close enough to confine the arc within the chamber."

Claims 2 and 20 relate to a combination by which the resilient contact holders are operable through the opening into the closed hood to actuate the movable contacts. Claim 20 may be regarded as typical and likewise has been arranged by plaintiff with its essential elements shown in italics. It is as follows:

"In an electric switch including a plurality of sets of cooperating stationary and movable contacts (8-37), a plurality of chambers (39) enclosing said sets of contacts and having openings into the interior thereof, a set of stationary contacts (8) secured to one wall of each of said chambers, a carrier (20), a plurality of movable contact sets (37) carried by said carrier, resilient means (28) between said carrier (20) and each of said movable contact sets, and shields (31) surrounding said resilient means (28) and movable in said openings for substantially closing the same."

The court below, after a lengthy trial in which numerous expert witnesses were heard, filed an opinion and made extensive findings of fact upon which its judgment was predicated. While considerable criticism is directed at the lower court's opinion and conclusions, it is evident that it gave careful and painstaking effort to the difficult and complicated problems presented. The court held the patent invalid on numerous grounds. We shall first consider its conclusion that the claims in suit "are invalid for lack of invention in view of the prior state of the art." As to this conclusion, the court in its opinion stated: "The Wilms and Petersen patent does not show an invention. They designed a hood which is completely enclosed except for a single opening in the bottom through which the actuator passes. This is a mere mechanical device permitting the moving of the movable contacts into connection with the fixed contacts. Wilms and Petersen when they designed the hood had no other thought in mind than this."

The court made numerous findings in support of this conclusion, the most pertinent perhaps being findings 6, 9, 10, 24, 25, 26, 29 and 30.

"6. At the time the application for the Wilms and Petersen patents No. 2,071,149 was filed in the Patent Office (July 11, 1935) plaintiff was the owner of Wilms and Dawe patent No. 1,981,534 which disclosed a double-break vertical acting switch having a hood enclosing the contacts which was of practically the same design as the switch described in the Wilms and Petersen patent except that in the Wilms and Dawe patent the hood was formed in one piece with the bottom of the hood left open and the springs which supported the movable contacts were not enclosed in telescoping spring cups."

"9. * * * Plaintiff admitted that the enclosure disclosed in the application was of the same order as in Thomson patent No. 1,375,983 and Ancotti et al. patent No. 1,310,111 cited by the Examiner, but asserted that complete enclosure, if acquired at the expense of accessibility of the contacts, would result in failure. None of the claims in suit refers to accessibility of the contacts."

"10. In addition to the Thomson and Ancotti et al. patents cited by the Examiner, the Wurts patent No. 470,161, Henderson patent No. 777,631, Hewlett patent...