“application of a known technique to a piece of prior art ready for the improvement"
The Examiner found that Blair’s vehicle A/C system includes all but the required economizer heat exchanger (hereafter “economizer”). (Ans. 4.) In view of the economizer 43 of Zheng’s vehicle A/C system, the Examiner determined that it would have been obvious to add an economizer to Blair’s system for increased performance. (Id.) In addition, the Examiner noted that economizers were known to increase system efficiency. (Id.)
We find no error in the Examiner’s determinations. Zheng shows that economizers were known to improve the capacity of vehicle A/C systems, particularly by further subcooling the refrigerant supplied to an evaporator. (Zheng, col. 7, ll. 30-33.) Given this benefit, the proposed addition of an economizer to Blair’s vehicle A/C system constitutes a prima facie obvious “application of a known technique to a piece of prior art ready for the improvement.” KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 417 (2007). (...)
Appellants’ arguments are not persuasive. Appellants fail to present evidence that Blair’s system would not have been understood as benefiting from subcooling by an added economizer. For example, Appellants allege but fail to establish that, despite Zheng’s express teachings of increased capacity, vehicle A/C economizers would not have been understood as increasing capacity.2 See Estee Lauder Inc. v. L’Oreal S.A., 129 F.3d 588, 595 (Fed. Cir. 1997) (arguments cannot take the place of factual evidence).