Robert H. Clark Co Expansive bit.

[Geoff Emms]

Hi all,
I'm chasing some info about this relatively modern expansive bit I recently purchased. It's a No 250 made by Robert H. Clark Co. of Beverly Hills and is marked on the back "Pats Pend USA". I'm trying, without success, to find the patent for this bit.
I've found two patents for expansive bits by H C Wilson assigned to Clark (2496427 & 2577986) both from the 1950's but neither of them for this bit. Any help will be appreciated.
Cheers,
Geoff.

[Jim Koepke]

It is possible the patent was not issued for this design.

My search turned up patents for William Clark patents for expansive bits from the 1850s:

https://patents.stackexchange.com/questions/16003/william-a-clark-extended-expansive-bit-patents

Then there is some advertising from 1953:

Google Books (https://books.google.com/books?id=x9wDAAAAMBAJ&pg=PA357&lpg=PA357&dq=Robert+H+Clark+expansive+bit+patents&source=bl&ots=AaY3vUXqxs&sig=ACfU3U0IR1ZKBtz19K5a3u05U9FVmNs7nw&hl=en&sa=X&ved=2ahUKEwjaleyGyvbhAhWxJjQIHd6YDmgQ6AEwEXoECGAQA Q#v=onepage&q=Robert%20H%20Clark%20expansive%20bit%20patents&f=false)

That is enough searching for me.

jtk

[Geoff Emms]

Thanks Jim,
I tend to agree with you that they might not have bothered patenting it. The advert' you linked to appears quite frequently from about 1950.
But hey, what about the advert for Luma-rim! I want a set of them...only $2.95.
Thanks for making my day.
Cheers,
Geoff.