Dimensions types in gears US/Euro

[FrenchCAD]

Hi guys,

I'm currently designing gears for a University's assignement I have. To help me, I use the "Design of machine elements, 7th edition" book, from Spotts & Shoups, edited by Prentice Hall.

At the gear chapter, they use a pitch diameter and circular pitch that I have no clue what it is. How can I relate this to modulus, diameter or whatever I know? Because it isn't explained anywhere in the book.

I guess it is because of a difference of standard dimensions between US and Europe. Will we agree one day? ;-)
Regards, FrenchCAD
Université Joseph FOURIER
Département Génie Mécanique
Grenoble
France
cyril.guichard@wanadoo.fr

 

[FrenchCAD]

Ok, I found what pitch diameter is, it's just number of teeth per inch.

Still looking for circular pitch FrenchCAD
Université Joseph FOURIER
Département Génie Mécanique
Grenoble
France
cyril.guichard@wanadoo.fr

 

[gearguru]

diametral pitch is no of teeth per 1 inch
circular pitch is a distance between corresponding points on two neighboring teeth measured on the pitch diameter (it is the length of an arc!)
You can calculated it when you divide the cicumference of the pitch diameter by No of teeth.
gearguru

 

[FrenchCAD]

Thanks again man, you rock! ;-)

I wasn't sure that circular pitch was just the pitch applied on a circle. FrenchCAD
Université Joseph FOURIER
Département Génie Mécanique
Grenoble
France
cyril.guichard@wanadoo.fr