Undiscovered newer generation 2001 and Thunderbeam patents?

[auggatronic]

So, I got bored and decided to surf Google Patents, and stumbled upon a odd-looking Thunderbeam and 2001 expired siren patent. I'm guessing they are second generation designs or new designs. I haven't seen any photos or videos related to these sirens at all. After reading the description, it is said that they run on a DC motor, and that they have battery backup. Any information about these siren designs would help!

Link to the patent: https://patents.google.com/patent/US4847590A

[Reactor Cat]

Cool discovery. The 2001 looks like it's a full-on round back. Like the 2001-DC round back but the entire back is rounded. Also from the pictures, It looks like it has a design similar to the tempest with the output cones. And the thunder beam looks like the top is protecting the motor. I'm not that familiar with federal sirens but from looks that is what I got.

[Model L]

I believe this is the original patent for the 2001 series. concept drawings that were later revised into the 2001-SRN. It was applied for in 1988, and granted in 1989. 2001 production began the same year (1988) , with the original 2001-srn roundback being manufactured. as for the thunderbeam-esque design nothing ever became of it, and to my knowledge no prototypes or installs have ever been seen.

[siren fan]

Nice find!