153 F.2d 523 (2nd Cir. 1946), 159, Engineering Development Laboratories v. Radio Corp. of America

Docket Nº:159.
Citation:153 F.2d 523, 68 U.S.P.Q. 238
Case Date:February 04, 1946
Court:United States Courts of Appeals, Court of Appeals for the Second Circuit

Page 523

153 F.2d 523 (2nd Cir. 1946)

68 U.S.P.Q. 238




No. 159.

United States Court of Appeals, Second Circuit.

February 4, 1946

Page 524

Samuel Ostrolenk, of New York City (Sidney G. Faber, of New York City, of counsel), for appellant.

Stephen H. Philbin, of New York City, for appellee.

Before L. HAND, CLARK, and FRANK, Circuit Judges.

L. HAND, Circuit Judge.

The plaintiff appeals from a judgment, summarily dismissing its complaint for the infringement of a patent issued to one, Cisin, for an 'Amplifying Circuit.' The only question is whether the claims in suit are invalid because they were introduced into the application more than two years after the subject-matter which they cover had been publicly sold. The disclosure is of an electric circuit which will increase the volume of the electrical pulses produced in a second circuit 'in the usual manner by the action of sound waves on the transmitter' (page one, col. two, lines 49, 50). The first circuit contains a 'rectifying tube' and an 'amplifying tube' in series, set in the usual house circuit, which by hypothesis may carry either direct or alternating current. When a direct current is used, the 'rectifying tube' merely allows it to pass through unimpeded. When an alternating current is used the 'rectifier' stops, or 'stains out' the pulses of current in one direction, letting the current which arrives in the opposite direction pass through to the 'amplifier.' Between the 'rectifier' and the 'amplifier' is a 'filter, ' designed to 'smooth out' the pulses of the 'rectified' current. The anode of the 'rectifying tube' contains not only the usual anode 'plate, ' but a 'grid' such as is necessary in an 'amplifying tube' in order to impress upon the amplifying current the pulses of the current which is to be amplified. In the disclosure this 'grid' is connected directly with the input lead of the house circuit to which the 'plate' of the anode is connected, so that it is electrically unnecessary. (This connection is apparently what the claims mean when they speak of the 'plate' and 'grid' as being connected 'in multiple.') The specifications do not disclose why the 'rectifying' tube should contain the 'grid'; but it was explained at the bar that, as such tubes were on the market for use in 'amplifying' tubes, they could be made also available for the 'rectifier' by the mere expedient of connecting the 'grid, ' as we have described. In parallel with the circuit containing the electrodes are two heating 'filaments, ' one in each tube to heat each cathode, as is well understood; but, since either a direct, or an alternating, current will heat the filaments equally well, there is no need of a 'rectifier' in this circuit. In order 'to prevent burning out of the filaments' in both tubes, resistances in series are added between the filaments and the source of power, and one of these 'may be a variable resistance, if desired' (page one, col. one, lines 50, 51).

The claims in suit may for convenience be divided into two groups: one, consisting of Nos. 3, 4 and 5; the other, of Nos. 11, 12 and 13. The only difference between claim 3 and claims 4 and 5 is that claim 4 includes the resistance just mentioned and claim 5 specifies it with particularity. There is even less difference between claim 11 and claims 12 and 13: all three contain the same...

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