Alan Long Thien Du

3 Patents

• US123597352025

  Spring Stop for Clapper Valve

  Acorn Engineering Company, Inc.

  0 cites
• US122921232025

  Clapper with an Upstream Cam-arm and Roller Arrangement

  Acorn Engineering Company, Inc.

  0 cites
• US119767362024

  Eccentric Backflow Preventer

  Acorn Engineering Company, Inc.

  0 cites