fly on little wing
Join Date: Mar 2003
Location: Western Michigan
The USPTO link is your best search tool.
The quick search feature with Term 1 and all fields will get you started.
Start reviewing the search hits.
Then you can also look at the references sited.
If you are looking for a US patent, it's in there.
Regarding US patent 4,524,540.
Independent Claim 1 and the dependent Claims 2 and 3 is the triangle taper.