Assignee
Inventors
- Donald L. Parker (56 patents)
- Donald Edward Schenk (39 patents)
- David Fredrick Reuter (57 patents)
- George N. Villec (9 patents)
- Alexander Kade (35 patents)
- Robert J. Hammersmith (10 patents)
- James F. Quinn (3 patents)
US Patent 4938543 · Granted Jul 3, 1990