# Keeler Leonarde — Patents explained on PatentBrief

Keeler Leonarde has 1 landmark patent explained in plain English on PatentBrief.

- [Leonarde Keeler's Early Mechanical Blood Pressure Recorder](https://patentbrief.org/patent/us/1788434/polygraph-lie-detector-keeler) — granted 1931
  A 1925 invention by Leonarde Keeler designed to mechanically record a patient's arterial blood pressure over time.

**Full profile:** https://patentbrief.org/inventor/keeler-leonarde

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