(dissenting).
While I join in the dissenting opinion written by Judge Rich, I think it is desirable to amplify the discussion of an important point which arises in the following excerpt from the majority opinion:
“ * * * in view of the obvious similarity in function between the terminal heads in the resistors of the Megow patents and the conventional dumbbell shaped head employed in the resistor art, use of the latter in the Megow type resistor is considered an obvious choice of terminal head to one skilled in the art.” [Emphasis added.]
First, I am at a complete loss to determine where, in the prosecution of this application, an issue of “similarity in function” was raised. The majority thus predicates its opinion on what I believe to be a totally new ground of rejection, stated for the first time in the present majority opinion of this court. 35 U.S.C. § 144 requires that our decision “shall be confined to the points set forth in the reasons of appeal.” I do not find the issue of similarity of function set forth in any reason of appeal herein. This is due, I think, to the fact that issue was not raised by either the examiner or the board. Thus appellant did not argue the factual questions raised in connection with this issue. To deny now his claims on this basis, as the majority would do, seems to me to be a denial of appellant’s right to be heard.
Moreover, I agree fully with the view of Judge Rich in his dissenting opinion that such a statement merely begs the statutory question of obviousness of the invention. As Judge Rich indicates, we have held in the several cases which he cites that functional similarity per se cannot be equated with obviousness.
If, however, we assume the propriety of making such a new ground of rejection, it should be predicated on the technical facts rather than upon judicial assumptions of such facts. The judicial assumption of technical facts upon which the majority would act is clearly and demonstrably wrong. The dumbbell-shaped head used by appellant is not “conventional” in any resistor art of record. While Steenweg shows a dumbbell-shaped terminal head, the significant technical differences between the Steen-weg resistor and that of appellant make a comparison of the terminal heads wholly without significance. In Steenweg, the terminal head is not imbedded in resistive material as are the terminal heads claimed by appellant. Instead, the Steenweg terminal head is imbedded in *624a core of insulating composition which can have no effect upon the resistance value of the resistive element. This core merely serves to hold the terminal head firmly in place. Electrical connection is made between the upper, cap-like portion of the terminal head and the end of the resistive element. The Steenweg device is of relatively high power, and is used to absorb transient, high voltage oscillations which interfere with automobile radio reception. Because of the transient nature of the energy dissipated, because of the relatively large size of the resistor, and because of the location of the resistive element, arrangements for carrying away the heat generated in the resistive material do not depend so critically upon the thermal conductivity char-actertistics of the portion of the terminal head which is embedded in the insulating core. Further, there is no problem of electrical contact and conductivity with respect to the embedded portion of Steen-weg’s terminal head.
Such is not the case with appellant’s device, however. As stated in the specification, appellant’s terminal heads are “highly conductive of both electricity and heat,” and further:
“It should be noted that any loosening of the helix [of the prior art frusto-conical terminals], even though so slight as to be unobservable, or any cracks in the resistance path, even though so slight as to be unobservable, are apt to change appreciably the electrical characteristics of the resistor.”
Thus, appellant faced at least three distinct problems with respect to terminal head design which were of little or no consequence to Steenweg: 1) the need for a terminal head which would provide good thermal contact and conductivity, since the only effective way to dissipate heat generated in the resistive material, in a resistor like appellant’s, is to conduct it away by means of the terminal leads; 2) the need for a terminal head which would provide good electrical contact and conductivity; and 3) the need for a terminal head whose mechanical design would resist displacement due to stress and thus ensure continued good physical contact with the resistive material.
There is no doubt that appellant’s device overcomes these problems and there is no doubt that the Steenweg device is not subject to them. There is no suggestion in any prior art of record that appellant’s dumbbell-shaped terminal head would be effective to establish and maintain satisfactory electrical and thermal contact with the surrounding resistive material and also to provide sufficient thermal conductivity. The areas of contact between appellant’s dumbbell-shaped heads and the resistive material result not only in high mechanical strength, but, even more importantly, they provide the intimate surface contacts necessary to assure both electrical and thermal stability.
We are dealing here with electrical devices of a relatively high order of precision. They are effective only so long as they retain that precision. Thus a resistor of a certain rated wattage and resistance must retain those characteristics within predetermined tolerance limits if it is to be effective. Heat build up in such a x*esistor can so disrupt the electrical path that the x'esistance may well fall outside the set tolerance limits; indeed, it may destroy the x'esistor altogether. Excess heat may also affect adversely the physical contact between the tex'minal heads and the resistive material, resulting in further undesix'able variation in the operating characteristics of the resistor. There is no suggestion in any of the art of record of any “similarity in function” in these x-espeets.
I agree with Judge Rich that the appealed decision should be reversed.