Bevel gear - module/script/tutorial

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papyblaise
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Re: Bevel gear - module/script/tutorial

Postby papyblaise » Sat Jan 25, 2020 10:55 am

neither to nor bottom surfaces of the gear doesn't correspond to this PD.
If you don't know that , learn lot and lot mécanic ' s documents show my screenshot
PD: is the diamètre where two gear are contact nearly on the midel of the tooth
my darling is the Citroen one's
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gear.PNG
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looo
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Re: Bevel gear - module/script/tutorial

Postby looo » Sat Jan 25, 2020 11:04 am

papyblaise wrote:
Sat Jan 25, 2020 10:55 am
neither to nor bottom surfaces of the gear doesn't correspond to this PD.
If you don't know that , learn lot and lot mécanic ' s documents show my screenshot
PD: is the diamètre where two gear are contact nearly on the midel of the tooth
my darling is the Citroen one's
Judging from your image, you used an involute profile for a bevel gear. I don't know how often I said that already but a bevel gear needs a different profile due to different kinematics.
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papyblaise
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Re: Bevel gear - module/script/tutorial

Postby papyblaise » Sat Jan 25, 2020 12:07 pm

of course but the formula for PD is constant ; cylindrical , conical , helicoîcal , spiral , screw and wheel , ...
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Zuzzuk
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Re: Bevel gear - module/script/tutorial

Postby Zuzzuk » Sat Jan 25, 2020 5:10 pm

looo wrote:
Fri Jan 24, 2020 8:47 pm
For the base-geometry, you can have a look at the example here. In the end a ittle bit of math is unavoidable ;)
https://forum.freecadweb.org/viewtopic. ... 20#p103661
...
There is a property reset origin. Switching this to off will place the gear as it is placed in the example.
Hi looo,
Thanks a lot for answers - after switching "reset origin" to off everything took its place :) I do like geometry, so its math don't scary me :) Thank you again!
I've read, that usually PD for Bevel gear is measured at its biggest diameter section, but having your method in place probably works even better for further grooves making/shaping to own needs.
Regards
Konstantin
// per aspera ad astra
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EduBambu
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Re: Bevel gear - module/script/tutorial

Postby EduBambu » Tue Sep 08, 2020 2:54 pm

Good Morning!

I searched the forum archives on bevel gears ("serch the forum": bevel gear [enter]) and found a very busy history since 2015, but it has had less comments in recent years.

I got some good results using FCGear and making a data sheet before starting the design.

Par_conico03.png
Par_conico03.png (98 KiB) Viewed 141 times

Here is an example:

Par_conico01.png
Par_conico01.png (191.28 KiB) Viewed 141 times

The question I ask: - Is it still justifiable to return to this subject? Or, has it been fully clarified on some other topic, which has escaped my research?

Par_conico02.png
Par_conico02.png (213.67 KiB) Viewed 141 times

Also follow the examples of the data sheets for the conical pair of figures: 18-tooth pinion and 54-tooth crown. 3/1 ratio.
Attachments
Par_conico02b.pdf
(764.16 KiB) Downloaded 21 times
Par_conico02a.pdf
(763.82 KiB) Downloaded 16 times