----- Original Message -----
From: "John S. Denker" <jsd@MONMOUTH.COM>
To: <PHYS-L@lists.nau.edu>
Sent: Saturday, January 25, 2003 7:35 PM
Subject: Re: Segway info
| Bob Sciamanda wrote:
|
| > The Amazon ad for the Segway Human Transport includes some interesting
| > technical stuff. Go to:
| > http://www.amazon.com/exec/obidos/tg/detail/-/B00007EPJ6/ref=segway_tn_lef
t/103-6703733-8593400
|
| It says:
| "The number of teeth on each gear is chosen
| to produce noninteger gear ratios."
|
| Oh reeeeeeally?
|
| Such gears must be lubricated with 100% snake oil.
|
| Non-integer ratios would be quite astounding,
| considering that the gear ratio is equal to the
| number of teeth on one gear divided by the number
| of teeth on the other gear. It just cracks me
| up to visualize a gear with a non-integral number
| of teeth.
It is the RATIO which is to be non-integer, not the number of teeth.
EG: Teeth numbers of 24 and 12 have an integer ratio: 24/12 = 2.
OTOH teeth numbers of 24 and 13 have a non-integer ratio: 24/12 = 1.846. .
.
|
| Kidding aside, I suspect that they should have
| said "relatively prime" rather than "noninteger
| ratios". This is a good practice, and is well
| known (albeit not universally adopted) in mechanical
| engineering. . . .
This makes no sense unless you mean the teeth NUMBERS are relatively
prime, not the RATIO.