Issued Patents All Time
Showing 1–8 of 8 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5294236 | Effluent metering system | — | 1994-03-15 |
| 5086536 | Convertible vacuum cleaner | John R. Lackner, Stanley E. Grzywna, Ralph A. Weber | 1992-02-11 |
| 5007133 | Convertible vacuum cleaner | John R. Lackner, Stanley E. Grzywna, Ralph A. Weber | 1991-04-16 |
| 4947512 | Convertible vacuum cleaner | John R. Lackner, Stanley E. Grzywna, Ralph A. Weber | 1990-08-14 |
| 4829624 | Apparatus for producing cleaning suds | Stanley E. Grzywna, John R. Lackner | 1989-05-16 |
| 4573235 | Rug cleaning attachment | John J. Jailor | 1986-03-04 |
| 4514199 | Vacuum cleaner dirt box | Roger S. Ford, Herman Shie | 1985-04-30 |
| 4337663 | Device for testing the suction strength of an upright vacuum sweeper | — | 1982-07-06 |