Collapsible hyperbolic paraboloid umbrella
United States Patent 3252469
Inventors:
Peake, George H.
Publication Date:
05/24/1966
Assignee:
Peake, George H.
Other Classes:
211/197, 135/98, 52/80.200, 52/66
International Classes:
A45B23/00; A45B25/02; A45B25/00
US Patent References:
| 3060949 | Flexible hyperbolic paraboloid shelter | | | |