In re Armstrong

83 F.2d 924, 23 C.C.P.A. 1209, 1936 CCPA LEXIS 115
CourtCourt of Customs and Patent Appeals
DecidedJune 8, 1936
DocketNo. 3644
StatusPublished
Cited by2 cases

This text of 83 F.2d 924 (In re Armstrong) is published on Counsel Stack Legal Research, covering Court of Customs and Patent Appeals primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
In re Armstrong, 83 F.2d 924, 23 C.C.P.A. 1209, 1936 CCPA LEXIS 115 (ccpa 1936).

Opinion

Bland, Judge,

delivered the opinion of the court:

Appellant has appealed here from the decision of the Board of Appeals of the United States Patent Office, affirming that of the examiner denying patentability in view of the prior art of claims 13, 17 and 19 of his application for patent relating to a mercury switch. A large number of claims were allowed but none as broad as the claims here involved.

Claim 13 illustrates the nature of the subject matter involved and is representative of the three rejected claims. It follows:

13. A mercury switch device having a chambered body member comprising two commercially pure iron parts insulatedly mounted one upon the other with means rendering the chamber enclosed gas-tight, and arranged for connection with a source of gas under super-atmospheric pressure, said insulated parts Having respective conductive surface portions exposed interiorly of the chamber insulatedly spaced apart therein a substantial distance, said device being mounted for movement between two oppositely inclined positions; a body of mercury enclosed in the chamber in quantity sufficient to bridge the insulating space between said exposed surface portions, to establish mercury communications between them when the device is in one of said positions, and hydrogen gas compressed at a substantial degree in excess of atmospheric pressure sealed in said chamber.

The references relied upon are:

Tesla, 611719', October 4, 1898.
Clark, 783612, February 28, 1905.
Brown, 1369882, March 1, 1921.
Phelan, 1598874, September 7, 1926.
Stern, 1746369, February 11, 193,0.

Two additional references, Machlett, 1789556, of January 20, 1931, and Badger, 1691912, of November 20, 1928, were referred to by the examiner as “of interest,” and illustrate certain features of the prior art.

Appellant’s tilting tube mercury switch consists of an iron shell, closed at one end, a bolt-like member entering the opposite end, a soft rubber plug surrounding the bolt-like member and a partial [1211]*1211filling of mercury. The outer shell constitutes one circuit terminal, and the bolt-like member the other terminal, and the arrangement is such that the mercury makes and breaks the circuit as the switch is tilted.

Appellant’s switch is designed to be evacuated of air and filled with hydrogen gas and then tightly sealed. To permit of this the aperture through the rubber plug is made slightly larger than the electrode which passes through it and a washer having radial passages is placed under the nut on the end of the central electrode. In this manner is provided a passage for the gas through the radial passages of the washer and the annular space between the central electrode and the rubber plug, into the interior of the switch. Some of the features above described and others not herein involved or referred to are set out by the examiner.

The broad claims at bar, which were rejected on the prior art, call for a combination of the three following old elements, which combination of elements appellant relies upon for patentability of the claims:

(1) pure iron electrode
(2) hydrogen gas occupying the mercury-containing chamber
(3) Super-atmospheric pressure operating on the hydrogen gas in the chamber.

Claims 13 and 19 were rejected as uninventive over Clark in view of features of Tesla and Phelan.

Clark shows the general arrangement of a mercury switch having an outer metal shell closed at one end and a central electrode at the other end and with an insulating bushing interposed, all intended to function in the same manner as appellant’s device. The outer shell is of “iron or steel” and the switch is sealed tightly.

Phelan discloses electrodes of “substantially pure iron”, and an atmosphere of hydrogen at a pressure of substantially one atmosphere, and states that the electrodes are made from pure metals which are “substantially devoid of any impurities” and that the hydrogen “is in a high degree of purity.”

Tesla shows the use of gas under high pressure in a mercury switch. The gas, however, is ammonia and high pressure is used for the purpose of reducing the severity of arcing. His outer casing is of “iron, steel or other proper material.” His specification especially emphasizes the high gas pressure feature.

In discussing the Clark reference in connection with the rejection of these claims the examiner states that Machlett emphasizes the arc extinguishing properties of a gas which is under high pressure.

Claim 17 was rejected as unpatentable over Clark in view of Brown or Stern and in further view of Tesla and Phelan. The examiner stated that the gasket material referred to in the claim [1212]*1212could be of the form shown in Clark or could be arranged in connection with a bolt compressor, as in Brown or Stern, without involving invention. The examiner was also of the opinion that there was .no limitation in the claim to prevent the structure of the gasket from reading upon Clark and that it would be obvious to seal Clark’s .chamber air tight. Clark, while showing no filling means, also .states that the switch “may be exhausted of air.”' The examiner then calls attention to the fact that a filling means could be provided by the “filling stem” of Badger.

The appellant and the Solicitor for the Patent Office concede that the patentability of the claims depends upon whether or not invention was involved in combining the features which were separately taught in the prior art referred to. It is not denied by anyone that nil the features involved in appellant’s combination claims at bar are to be found in the prior art.

Appellant’s specification, and the affidavits which will be hereinafter discussed, emphasize as the important feature of his invention the fact that his device is so constructed that its life is many times the life of the ordinary commercial mercury switch which was on the market at the time he made his invention. The difficulty with the mercury switches used at the time appellant entered the field was that the electrodes became contaminated due to the passing of the electric spark through the gap in the making and breaking of the connection, so that, after about 100,000 makes and breaks, the switch would foul.

Appellant has shown by affidavits that tests were made by highly competent electrical engineers as to the durability of mercury switches other than apiDellant’s. These tests vrere based upon the number of makes and breaks in the circuit before the switches became so contaminated that they failed to function. It is true that he does not show that switches made in accordance with the Clark and Phelan patents, and filled with inert gas, at superatmospheric pressure, as the board has pointed out, were tested by these parties.

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Related

American Steel & Wire Co. of New Jersey v. Coe
105 F.2d 17 (D.C. Circuit, 1939)
Electrons, Inc. v. Coe
99 F.2d 414 (D.C. Circuit, 1938)

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Bluebook (online)
83 F.2d 924, 23 C.C.P.A. 1209, 1936 CCPA LEXIS 115, Counsel Stack Legal Research, https://law.counselstack.com/opinion/in-re-armstrong-ccpa-1936.