Robert L. Smith and the Filto System Pipe

Robert L. Smith is the American inventor who, after twenty years of pursuing a single idea, designed a metal-bodied filter pipe and produced it under the Filto name in North Carolina. His name appears in pipe history neither as a carver nor as a factory owner; his real trace lies in the three separate pipe patents he left in the registration record.

Because these patents document a single idea maturing step by step, they also serve as a fine example of why pipe patents are useful for dating.

The Patent Chain

Smith's first application is dated 3 April 1946 and was not granted until 17 February 1953, as No. 2,628,622. The document lists the inventor's name as Robert Lequeux Smith and his residence as San Diego. In this first design, the stem is a heat exchanger with fins opening outward: smoke cools as it travels along a helical path, then passes through a chamber packed with fresh tobacco. A second application, filed on 5 January 1949, resulted in a grant on 6 October 1953 as No. 2,654,370; here Smith's address is recorded as Portsmouth. This document describes a bowl-shaped baffle that redirects the smoke, paired with a replaceable, perforated-base filter basket packed with tobacco.

The third and best-known document was filed on 17 October 1963 and granted on 23 February 1965 as No. 3,170,468. This time the applicant had assigned rights to Burgaw-based Filto Pipes, Inc. The patent text explicitly references the two earlier documents and notes that an intervening application had been abandoned. Its innovation is twofold: the filter basket hangs inside the shank on two thin legs, allowing smoke to circulate around the basket's edges so tar cannot collect and block the passage. The flexible cap at the end of the stem snaps on and off like a press-stud. The basket's protruding tabs let the filter be pulled out and discarded without touching it by hand.