Assignee
Inventors
- Johnny W. Van Der Velden (3 patents)
- Theodorus F. van Bergen (1 patents)
- August L. H. Simons (4 patents)
- Johannes K. E. Colditz (7 patents)
- Martinus A. C. Ligtenberg (2 patents)
- Franciscus M. Dreesen (1 patents)
US Patent 5008591 · Granted Apr 16, 1991