Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
CA713960A
Inventor
H. Ripple Melvin
A. Humphrey Warren
W. Helm Mark
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hoover Co
Original Assignee
Hoover Co
Publication date
Application grantedgrantedCritical
Publication of CA713960ApublicationCriticalpatent/CA713960A/en