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DerbyDad03 DerbyDad03 is offline
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Default How do extendable snow brushes work?

DD_BobK wrote:
On Feb 9, 7:31 pm, DerbyDad03 wrote:
I've got a snow brush that can be set to various lengths by turning it in
one direction to loosen the inside tube, setting to the length you want and
then turning it in the other direction to lock it down. There are no
pre-determined lengths, like indents or anything like that. It can be set
to any length within it's upper and lower limits.

...snip...

So what is inside the tube that allows the tubes to loosen and slide and
then tighten back down and lock? Could the cold affect whatever the locking
mechanism is?


I believe that most of these "infinitely" adjustable telescoping poles
have an eccentric element that tightens / "jams" against the tube ID.

Patents are not the easiest way to understand a mechanism
check this out & click on the "drawing" selection

http://www.google.com/patents/US4076437

cheers
Bob


Thank you for offering something other than "you have a low quality brush".