Surging investment by Chinese companies in U.S. research labs is yielding a fast-growing trove of patents, part of a push to mine America for ideas to help China shift from being the world’s factory floor to a driver of innovation. Largely absent from American research hubs a decade ago, Chinese firms including Huawei Technologies (HWT.UL) and ZTE Corp are now using U.S. researchers to create patents ranging from new software to internet infrastructure, according to an analysis of Thomson Reuters’ global intellectual property database.