Inventor · disambiguated record
David J. Helffrich
Also filed as: HELFFRICH DAVID J · HELFFRICH DAVID T
3 granted patents·1 pending application·102 citations·filing 1981–2004
72Inventor score
Top patents by PatentIndex Score
4 records- 0185US4959795AInsertion machine with distributed chargebackBELL & HOWELL CO·Filed 1989·Granted Sep 25, 1990·75 cites·22 claims
- 0259US5321624AInsertion machine having multiple document detectorBELL & HOWELL PHILLIPSBURG·Filed 1992·Granted Jun 14, 1994·26 cites·15 claims
- 0339US2006101517A1Inventory management-based computer vulnerability resolution systemBANZHOF CARL E·Filed 2004·Application pending·0 cites
- 0426US4479050ASensor alignment circuit and method of operationBELL & HOWELL CO·Filed 1981·Granted Oct 23, 1984·1 cites·18 claims
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →