Quick Action Ignition Co. v. Maytag Co.

39 F.2d 595, 4 U.S.P.Q. (BNA) 475, 1930 U.S. App. LEXIS 4132
CourtCourt of Appeals for the Eighth Circuit
DecidedFebruary 20, 1930
DocketNo. 8555
StatusPublished
Cited by2 cases

This text of 39 F.2d 595 (Quick Action Ignition Co. v. Maytag Co.) is published on Counsel Stack Legal Research, covering Court of Appeals for the Eighth Circuit primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Quick Action Ignition Co. v. Maytag Co., 39 F.2d 595, 4 U.S.P.Q. (BNA) 475, 1930 U.S. App. LEXIS 4132 (8th Cir. 1930).

Opinion

STONE, Circuit Judge.

This is an aetion for infringement of three patents. The trial court found patent Oglesby No. 1,279,750 valid but not infringed and patents Oglesby No. 1,300,637 and No. 1,390,376 invalid. Prom a decree dismissing the bill, this appeal is brought.

All of these patents relate to a fly wheel magneto designed to furnish electrical energy in the operation of gas engines.. The main patent is No. 1,279,750, which is for a magneto. Patent No. 1,300,637 is for an arrangement permitting access to the parts of the above magneto, and patent No. 1,390,376 is for a speed governor thereon to control non-load conditions.

Patent No. 1,279,750.

This is a combination patent. The question is whether it should be allowed a range of equivalents which will include the device used by defendant. This requires determination of the scope and extent of novelty disclosed by the patent and of a restriction by estoppel claimed to be shown in the file wrapper.

The power source in gas engines is explosions of gas (within cylinders) ignited by an electric spark. The more intense this spark, the more perfect the explosion. The intensity of the spark depends upon the imtensity of the electrical current producing it.One method of supplying this current is from a magneto. A magneto is a magnetic-electric unit .which generates electrical energy and places it on a conductor carrying to the spark plug in the gas cylinder. The main elements of a magneto are a permanent magnet and an armature. A magneto generates the current by arousing and concentrating a magnetic flux in the permanent magnet and passing that flux to the armature, from which it flow's by conductors to the spark plug. The current originates in the magnet, and only such current as can be so originated and passed therefrom- into the armature is available for use. The method of developing current in a magneto is to have a permanent magnet and an armature pass close to each other. This generates and develops the magnetic flux in the magnet which flows from its poles, or ends, into the armature coil. To produce this result, either the armature or the magnet may be fixed while the other revolves.

The ultimate purpose of Oglesby was not merely to produce a spark but to produce an intense spark. Such intensity was his aim. This he sought to do by intensifying the current produced in and transmitted from a magneto. Since the intensity of the usable energy produced in a magneto depends upon the intensity of the magnetic flux aroused in the magnet and transmitted by it to and received by the armature, his problem was a magneto- so constructed that, in its operation, there would be “a sudden forced building up of a dense magnetic flux through the armature coil.” Patent, p. 1, line 21.

His method and structure for working out the above result was as follows. He employed the well-known type of magneto where the magnet revolved in relation to a fixed armature. His improvements thereon were designed to effect an arrangement of parts which would bring about a unique sequence of results culminating in a more intense current to be transmitted to the spark plug. These results were produced “through the medium of a short air gap [in the magnet] active at a large distance from the center of rotation [of the magnet]; the entire bridging of the air gap in advance of coil induction ; suddenly sweeping a unidirectional flux across the coil under a shorter time constant than is possible when the flux is reversed; and in subjecting more turns of the coil to induction due to an increased coil space provided under projecting heads without sacrificing the bridging effeet.” Patent, p. 2, line 116.

To secure the “short air gap active at a large distance from the center of rotation” of the rotating magnet, he employed a cir[597]*597cular permanent magnet secured to the outer portion of a flanged disk support fastened to a revolving shaft driven by the gas engine to which the energy was to be supplied. This gave him the maximum rotation of the magnet, and thereby the greater opportunity to develop magnetic flux by rotation of the magnet. He made the magnet ends of highly permeable pole pieces which resulted in concentration of magnetic flux therein, when the magnet was revolved.

The armature was secured to another disk with suitable space between it and the magnet. This disk was practically stationary, being subject only to “rocking” for the purpose of advancing or retarding the spark. The armature pole heads were on the same side of the center of the disk and of the coil or coils, and they projected toward each other. This arrangement of the heads upon the same side of the disk center secured the unidirectional flux — desirable because it produced a more sudden and intense peak at slow speeds of magnet rotation. The projection of the heads toward each other gave, also, a larger space around the armature core, which space was utilized by more windings of the coil or coils, thus giving increased receptivity to the flux transmitted from the magnet. Also the projection of the heads toward each other enabled a shorter air gap to be used in the magnet, resulting in a more rapid and increased flux variation for each revolution of the magnet.

Another important feature is the lengths of the permeable magnet pole pieces, of the magnet air gap, of the outer face of the pole heads of the armature, and of the space between sueh pole heads. All of these lengths are the same, or practically so. The value of this is to secure a momentary short circuit of the flux leakage as an armature head spans the magnet gap just before the magnet pole is swept across the armature coils, thus enabling the full force of the flux to sweep across the coils immediately afterwards.

Thus an increased magnetic flux is developed by a large rotation and small air gap of the magnet; this flux is concentrated in the magnet pole pieces by making those pieces of highly permeable material; the lengths and arrangement of magnet air space, magnet pole pieces, and armature heads is such as to momentarily short circuit leakage and enable the full force of the flux to suddenly and strongly flow into the coils; those coils are increased in winding so as to take up the flux and generate a stronger current; the flux is unidirectional. Summarizing, the purpose and result is to develop an intense magnetic flux in the magnet and to transmit sueh flux, suddenly and with minimum loss, to the generating armature, where it is transformed into intense current ready for transmission to the spark plug. The record convinces that Oglesby’s magneto was highly effective and useful.

It seems logical to determine first just what Oglesby was granted by his patent while it was in course in the patent office. No matter what he had invented, the grant of his patent must be limited to the claims therein and the first measurement of the breadth of those claims must be what took place in the patent office in direct connection with such grant. He cannot broaden the scope of the claims to secure something shown to have been denied him by sueh proceedings in the Patent Office. I. T. S. Rubber Co. v. Essex Rubber Co., 272 U. S. 429, 443, 47 S. Ct. 136, 71 L. Ed. 335; Weber Electric Co. v. Freeman Electric Co., 256 U. S. 668, 677, 41 S. Ct. 600, 65 L. Ed. 1162, and the following cases in this court: R. H. Buhrke Co. v. Brauer Bros. Mfg. Co. (C. C. A.) 33 F.(2d) 838, 839; Knick v. Bowes, etc., Corp. [C. C.

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Bluebook (online)
39 F.2d 595, 4 U.S.P.Q. (BNA) 475, 1930 U.S. App. LEXIS 4132, Counsel Stack Legal Research, https://law.counselstack.com/opinion/quick-action-ignition-co-v-maytag-co-ca8-1930.