Richard L. Zelinka

DC Donaldson Company: 2 patents #358 of 695Top 55%

📍 Maplewood, MN: #253 of 510 inventorsTop 50%

🗺 Minnesota: #23,881 of 52,454 inventorsTop 50%

Overall (All Time): #2,320,046 of 4,157,543Top 60%

Patents All Time

Issued Patents All Time

Showing 1–2 of 2 patents

Patent #	Title	Co-Inventors	Date
5066400	Self-spaced pleated filter	Gary J. Rocklitz, Douglas G. Crofoot	1991-11-19
4650506	Multi-layered microfiltration medium	Marty Barris	1987-03-17