Hello,

I want to do the conception of precise Spur Gears to manufacture.

Does someone have the equation for the curve so I can use to sketch the teeth.

This is the Gear I want to do precisely.

I use SW 2016

Thank you for your help

Hello,

I want to do the conception of precise Spur Gears to manufacture.

Does someone have the equation for the curve so I can use to sketch the teeth.

This is the Gear I want to do precisely.

I use SW 2016

Thank you for your help

What you have posted is a Solidworks tool box Gear. Not very good... in fact BAD.

(Only good for a graphical representation of the Real Thing)

Tool Box gear = GREEN

True Involute Tooth Form = RED

Attached here is, what I will call, the "Robust Involute Spur Gear Generator - Better 02.SLDPRT" The RED gear

using this file and only changing a few of the equations values yields a gear that is very close to the one you posted from the tool box.

You posted a 16 tooth, 20 deg pressure angle gear. It has a pitch diameter of 24mm thus a Diametral Pitch of .6666 (No Teeth/Pitch Dia)

This will give you a true equation driven involute tooth form.

Robert,

Should your model work for Modular gears? Or is there another version? I tried to create a 0.4MOD x 10 tooth gear & it came out very, very small. 0.18mm outside diameter when it should be 5.2mm. I used a conversion table to give me the DP which worked out to be 63.5950 for 0.4Mod.

Edit: Figured it out.....had to change my Unit system to inches

Cheers & great work.

Thanks to share, now to my is personal change to know, how is the correct way to made a involute gear profile.

I see one pal here and has a good definition but not it's the same as a standard profile definition.

Any DIN/SAE/BSI to take they definition of Profile? Metric an Imperial will be desired....

Thanks!

Rubén Rodolfo Balderrama wrote:

Thanks to share, now to my is personal change to know, how is the correct way to made a involute gear profile.

I see one pal here and has a good definition but not it's the same as a standard profile definition.

Any DIN/SAE/BSI to take they definition of Profile? Metric an Imperial will be desired....

Thanks!

You are welcome to use my parametric gear file. This gives an extremely accurate true involute profile. It is metric and setup to use a Design Table with the inputs in the green columns. Enjoy.

Sorry to revive this old thread, but it shows up straight from a google search for "Module Driven Involute Gear Solidworks".

I have searched far and wide for a tutorial on involute gear construction that is driven solely by module, number of teeth and pressure angle, however 100% of the search results have either some kind of error or are imperial. Your gear generator, while clearly well executed, is no exception.

As a machinist, I think of cutting gears from the perspective of which tool to cut them with, and this will always be driven by module, not diameter. Either engineering classes disregard this completely or there's something else I don't know that I don't know.

This video, while informative, is indicative of a metric gear curiously being driven by diameter: https://www.youtube.com/watch?v=0KOgNoIjYLE I would like to find a similar tutorial (or just a SLDPRT) that uses module as a driver.

Can you or anyone recommend something?David,

I also back in 2015 had searched and searched for a True involute gear template.

Basically to no aval… So I created one for my purposes.

One for a given pitch diameter and a given number of teeth.

The template I made worked… for the gears I wanted.

I “EDM” these custom gears for a very specialized piece of machinery I make.

I subsequently made a template for a more traditional / standard gear & refined the template

(so it would not break if one changed the tooth count to something above about 45 teeth)

and posted it --- (the template attached above in my prior post)

I have recently just run across this, it was in a February 2017 Gearsolutions article:

http://gearsolutions.com/features/parametric-geometric-modeling-of-a-spur-gear-using-solidworks/

So I emailed the author and said:

Back in 2015 I did this model:

With “if then” in the equations so the model would not “break” with a high (greater than about 45 teeth) tooth count.

I also used a similar methodology to yours to construct the template.

I would appreciate your feedback on my attached Solidworks ver 2018 model.

His reply:

“My dear Robert S. Conklin, thank you very much for the contribution that you make to my paper, I really appreciate it, you right, mines break with higher number of teeth. Your design is excellent as you can note still involute curve methodology. This type of designs is useful in future investigations.

I did simulate two gears of yours and works perfectly on the pitch diameter. the normal common of two involutes surfaces is tangent of their base circles. Contact occurs in a line of action.”

So with a few changes to the equations I came up with this attached model/template.

“Involute Helical Gear Generator - Module .8_24T_CW-(ZERO) or .00001 Deg Helix_25 PA.SLDPRT”

I have set the:

To ZERO or real close to it so the model represents a straight spur gear not a “Helical Gear“

(One could take this helical bit out altogether and have a True ZERO Deg gear BUT you or anyone can do that if they desire.)

And I set up a global variable: “MODULE”

Solidworks is amazing,

Just got to use it right & keep searching and searching for the answers on how to do that.

EDIT:

I re-attached a fixed "Involute Helical Gear Generator - Module .8_24T_CW-(ZERO) or .00001 Deg Helix_25 PA.SLDPRT"

It works better now when using it as a helical gear.

Also attached the same model as "Involute Helical Gear Generator - Module .8_24T_CW-25 Deg Helix_25 PA.SLDPRT"

Set at 25 Deg Helix Angle just to show.

As an example of my frustration, here is a HALF HOUR LONG video showing how to do exactly what I want to do in Solidworks... in Creo! The background music is an acquired taste.

https://www.youtube.com/watch?v=XagtlMvwOKQ

At this point I have to ask if there is a reason that finding this information is so difficult. Occam's Razor.

This is embarrassing, but after losing patience and posting the second comment, I found out this was modeling a fake spur gear in Creo. So it was driven by module but isn't a real gear.

Back to square one.

Module is just the metric version of diametrial pitch. Tooth profile is generated by an involute off the gear base circle

https://en.wikipedia.org/wiki/Involute_gear

https://en.wikipedia.org/wiki/Involute_gear

These two Wikipedia pages contain all the information one needs.

If one has a pressure angle and a pitch diameter -or- module and number of teeth plus pressure angle --> Bam! Off to the races!

Use the above information to derive the diameter of the base circle. The base circle is what one uses to build the involute. Build the involute using an equation-driven curve. Mirror, pattern, etc. etc.

What you have posted is a Solidworks tool box Gear. Not very good... in fact BAD.

(Only good for a graphical representation of the Real Thing)

Tool Box gear = GREEN

True Involute Tooth Form = RED

Attached here is, what I will call, the "Robust Involute Spur Gear Generator - Better 02.SLDPRT" The RED gear

using this file and only changing a few of the equations values yields a gear that is very close to the one you posted from the tool box.

You posted a 16 tooth, 20 deg pressure angle gear. It has a pitch diameter of 24mm thus a Diametral Pitch of .6666 (No Teeth/Pitch Dia)

This will give you a true equation driven involute tooth form.