US 9421713B2

US Patent 9421713B2, titled "Additive manufacturing method for printing three-dimensional parts with purge towers," was assigned to Stratasys Inc.. The inventors are William J. Swanson, Ronald G. Schloesser, and Gary Larson. The patent was filed on March 8, 2013, and issued on August 23, 2016.

Abstract:
The patent describes a method for printing a three-dimensional (3D) part using an additive manufacturing system. This method involves printing layers of the 3D part and its support structure from multiple print heads or deposition lines. These print heads or deposition lines switch between stand-by and operating modes between printing layers. Crucially, when a print head or deposition line is switched to an operating mode, a purge operation is performed. This purge operation involves printing a layer of at least one purge tower using that print head or deposition line.

Plain-Language Overview of Independent Claims:

• Claim 1: This claim describes a method for 3D printing that uses multiple print heads or deposition lines to build a part and a support structure layer by layer. The core of the invention is that when these print heads switch from a stand-by mode to an operating mode (between printing layers of the part and support structure), a "purge operation" is performed. This purge operation involves printing layers of at least one "purge tower" using the print head that has just been switched to operating mode.

• Claim 5: (Note: Claim 5 is also an independent claim as it does not reference any other claim. The provided patent text only includes claims 1-4 explicitly and then refers to "Claim 1, wherein the at least one pu". I will assume this is intended to be a complete independent claim. However, based on the provided text, Claim 5 is incomplete. I will proceed by stating that it's incomplete and will interpret what is available.)
  Claim 5 (incomplete in provided text): This claim appears to elaborate on the nature of the "at least one purge tower" from Claim 1. Without the full text of Claim 5, its complete scope cannot be determined.

• Claim 16: (Note: The provided patent text only shows claims 1-4 and then an incomplete claim 5. There is no claim 16 in the provided claims section. I will explicitly state this limitation.)
  There is no Claim 16 provided in the excerpt of the patent text. Therefore, a plain-language overview of Claim 16 cannot be provided.

Litigation Status:
The patent US9421713B2 is currently active and is set to expire on August 20, 2034. It has been involved in litigation, with the first worldwide family litigation filed on March 8, 2013. More recently, an IPR (Inter Partes Review) case, IPR2025-00321, was filed and is currently pending (Instituted). Additionally, there are US cases filed in the Texas Western District Court (1:24-cv-01511) and Texas Eastern District Court (2:25-cv-00465 and 2:24-cv-00644). No specific CAFC dockets for US9421713B2 were found for 2026 through the search.