# Bernard D Willis — Patents explained on PatentBrief

Bernard D Willis has 1 landmark patent explained in plain English on PatentBrief.

- [How Early Telephone Systems Managed Busy Lines Automatically](https://patentbrief.org/patent/us/1537326/insulin-extraction-and-purification) — granted 1925
  A 1925 patent describing a mechanism to automatically signal that a telephone line is occupied, preventing callers from interrupting an active conversation.

**Full profile:** https://patentbrief.org/inventor/bernard-d-willis

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_Source: PatentBrief — https://patentbrief.org. Plain-English explanations of US patents._