04007743 is referenced by 654 patents and cites 3 patents.

The pivotable struts of an umbrella-like shunt defect closure device are resiliently biased from a collapsed position to an expanded position by resilient and foldable flat ring sections which extend between the struts when the struts are in their expanded positions but which are folded between the struts when the struts are in their collapsed positions.

Title
Opening mechanism for umbrella-like intravascular shunt defect closure device
Application Number
5/623788
Publication Number
4007743
Application Date
October 20, 1975
Publication Date
February 15, 1977
Inventor
Larry W Blake
Costa Mesa
CA, US
Assignee
American Hospital Supply Corporation
IL, US
IPC
A61B 17/04
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