Case ID: f2d_480/html/0871-01.html
Source: Caselaw Access Project
Author: {"author": "LANE, Judge.", "license": "Public Domain", "url": "https://static.case.law/"}
Date Created: 2024-08-24T03:29:51.129683

Application of Torakichi NAKAGAWA.
    Patent Appeal No. 9064.
    United States Court of Customs and Patent Appeals.
    July 19, 1973.
    Linton & Linton, Washington, D. C., attorneys of record, for appellant. Ulle C. Linton, Washington, D. C., of counsel.
    S. Wm. Cochran, Washington, D. C., for the Commissioner of Patents, R. V. Lupo, Associate Sol., Washington, D. C., William H. Beha, Jr., Washington, D. C., of counsel.
    Before MARKEY, Chief Judge, and RICH, BALDWIN and LANE, Judges, and ALMOND, Senior Judge.
   LANE, Judge.

This appeal is from the decision of the Patent Office Board of Appeals sustaining the examiner’s rejection of claims 3, 4 and 5 of appellant’s application serial No. 684,592 filed November 13, 1967, entitled “Spark Plug Tester.” No other claims remain in this case. We affirm the board’s decision.

Rejected claim 3 reads as follows:
3. Portable apparatus for testing spark plugs comprising DC high voltage generating means, a relaxation oscillator circuit consisting of a capacitor connected between a pair of electrodes for connection to a test plug, and a high resistance connecting said capacitor to said high voltage generating means for producing a relaxation oscillation by a discharge of the test plug, and an indicator for indicating the voltage of the relaxation oscillation generated between both electrodes of said capacitor.

Claim 4 is dependent and recites that the generating means is composed of a high frequency generator, a transformer and a rectifying circuit. Claim 5 is also dependent and recites that the indicator is a DC ammeter.

The prior patents relied' upon by the examiner and the board are:

Mesh 2,430,069 1947
Cass 2,956,223 1960
Badger 3,042,835 1962

Claims 3 and 5 were rejected under 35 USC 103 as being obvious in view of Cass and Mesh. Claim 4 was rejected as being obvious in view of Cass, Mesh and Badger.

Cass discloses apparatus for testing devices such as gas tube diodes by the use of a DC high voltage source, a relaxation circuit including a capacitor connected across the device to be tested, a high resistance connecting the capacitor to the voltage source, and a DC meter for indicating the voltage produced across the capacitor. Mesh discloses apparatus for testing spark plugs by the application of high voltage and a voltage selector switch which indicates by its position the length of the spark plug gap. Badger discloses apparatus for determining the timing of spark ignition and includes a high voltage generating means utilizing a high frequency generator, a transformer, and a rectifying circuit.

Both Mesh and appellant apply a variable voltage to a spark plug and derive the voltage which causes a discharge to be initiated across the plug gap. Cass shows the use of a relaxation oscillator for producing charging cycles in testing diodes, and Badger teaches the use of appellant’s claimed high voltage generating means in spark ignition timing.

Appellant points out that his claims do not call for the oscilloscope as used in Mesh, nor a device for determining the breakdown voltage of a negative resistance diode as disclosed in Cass, nor a timing light as taught by Badger. Appellant contends that if the three references could be combined it would be hard to say what would result.

The rejection here is not based on combining the entire circuitry of three prior patents. The rejection is that it would have been obvious to one having ordinary skill in the art to use the relaxation oscillator system of the Cass diode tester to test spark plugs as suggested by Mesh, and that it would have been obvious to use a power supply such as used in Badger’s ignition timer in the test circuit of Cass. We agree.

The rejection of claims 3 and 5 as being obvious in view of Cass and Mesh, and the rejection of claim 4 as being obvious in view of Cass, Mesh and Badger is affirmed.

Affirmed.