According to my calculation, U.S. Patent 4,487,451 expired in February 2002. You need to speak with your patent attorney in private about this matter and should not discuss this any further in public. Good luck.
The above is general information ONLY and is not legal advice, does not form an attorney-client relationship, and should NOT be relied upon to take or refrain from taking any action. I am not your attorney. You should seek the advice of competent counsel before taking any action related to your inquiry.
You did well by having Patent and Business Attorneys advise about your invention and release. I am not sure I understand how an insurance claim impacts this infringement issue as your patent was issued in 1984 with a priority date of 1982. It is noteworthy that patent grants are limited monopolies and that term is 20 years max, from date of filing (for your patent). Whether you have an infringement issue today (as you note you have papertrail) might be sorted out with the help of an experienced patent attorney.
Best wishes as you discuss with your attorney.
This is not a legal advice as I do not have an attorney-client privilege with you. You should retain a lawyer before acting on any generally available advice.
You may not understand one key fact: part of the bargain for getting your patent was that, after it expired, anyone would be free to use that invention without any compensation to you.
As you have been advised by others here, if you want to go through the details, you should probably speak to a patent lawyer privately who can get the facts and advise you accordingly.
This information is intended to be general and educational in nature. It is not intended to be specific legal advice or establish an attorney-client relationship. I require a signed retainer agreement from a potential client to establish an attorney-client relationship and before I will provide specific legal representation.
Your patent has expired and, therefore, you have no right to enforce it against anyone. It sounds like a case was already litigated, and a settlement achieved. Since the patent has already expired, it is hard to conceive of a circumstances under which you would be entitled to additional compensation. However, perhaps there is more to this story than meets the eye. If so, you should retain patent litigation counsel in New Jersey or New York (I practice in both states) to review the situation and advise you. Your investment in a few hours of lawyer time will tell you whether you have claims that are worth pursuing.