124 F.2d 521 | D.C. Cir. | 1941
This is a suit under R.S. §§ 4915, 4916, 35 U.S.C.A. §§ 63, 64, to obtain the reissue of a patent. It has been assumed, and we assume without deciding, that the only question is that of invention. The application relates to surge valves for hydraulic presses. The claims include, among others, all those of the patent to be reissued, which is Ernst, No. 1,892,568. These old claims have been re-allowed. The controversy relates to new claims 7 to 11 and 21 to 25, all of which have been rejected by the Patent Office and the District Court for lack of invention.
The re-allowed claims disclose a surge tank “mounted above”, or “mounted on top of”, or “supported on top of”, or “supported directly above”, the ram cylinder. The rejected claims describe the cylinder as “immediately adjacent” the surge tank, or describe the tank and cylinder as “adjacent and directly connected”, or the like. Some of the rejected claims refer to a “minimum length of path”, or a “substantially direct straight path”, or a “port”, between tank and cylinder. The prior art includes appellants’ own Ernst patent No. 1,672,561, for a high-speed hydraulic press. If the rejected claims differ materially from those of that patent, it is in the features just stated. We cannot say that the shortening, straightening, or replacement by a port, of the connection between tank and cylinder, in order to reduce resistance and increase speed, is inventive. On the contrary, as the Commissioner of Patents states in his brief, “it is elementary that resistance to fluid flow increases with the length of the conduit and with the number of changes of direction. There can be nothing unexpected, therefore, in the idea that the minimum resistance in flow between two containers will be achieved if they are placed directly in contact and the flow takes place as nearly as possible in a straight line.”
Affirmed.
