The patents are divided into two groups: company related patents and non-company related patents, these last an indication of a wider interest than just conduit fittings and tools. Each column is in chronological order, and the non-company patents start before the company ones do. The products listed here were invented by no less than three generations of Briegels, and in some cases, others were also involved as well. The last company patent appears to have been invented by my uncle. These may not be all the patents, as there are some products not represented here, but they are all I have been able to find. US patents issued prior to 1975 are not searchable by as many criteria, and all of the Briegel patents fall into that time frame. Patent 1,998,653 is troubling because it says the original patent was divided and resubmitted, and though the application number for the first attempt is listed there, you can't search for it by application number. The "Red Throat" insulated fitting patent is also noteable in its absence. The Canadian patent was issued on 10/01/57, but to this point I have been unable to find the corresponding US patent. There are only 6 Canadian patents, but only 4 of those have US counterparts on my list. I may get around to listing the Canadian ones as well, but for now, the patent numbers are listed at the end of each US link.

The U.S. Patent Office discourages linking to individual patents at their site, probably because they make no promise the links won't change. I have provided copies downloaded from there to save you the hassle of doing the searches yourself. All the information and images are part of the public record and hopefully pose no legal issues.