double-circular-arc gear generator software
double-circular-arc gear generator software
(OP)
Does anyone know of a gear generator for CAD systems that will produce double circular-arc gears? Both internal and exxternal? I am working with solidworks. Please post your suggestions. thanks.





RE: double-circular-arc gear generator software
Barring that, please feel free to post any thoughts on this gear tooth design, positive and negative, when compared to involute gear tooth profiles.
RE: double-circular-arc gear generator software
RE: double-circular-arc gear generator software
Would still appreciate any comments regarding experience with double circular-arc gear tooth profiles...
RE: double-circular-arc gear generator software
You can purchase a GCode Generator from here: http://www.delphusa.com/index.htm
Cycloidal gears tend to mesh with pure rolling action and are therefore more efficient than an involute profile.
A quick search on Google will reveal a wealth of information on the subject of the pros & cons of using either of these profiles.
As to why anyone would consider using the Cycloidal profile in a general industrial spur gear application is beyond me.
Some cons:
1. Tooling to generate the profile is near impossible to find off the shelf and would therefore be extremely expensive to produce.
2. There are no load rating standards available to validate a design.
3. Generally only used in very low load applications such as time keeping devices.
Ron Volmershausen
Brunkerville Engineering
Newcastle Australia
http://www.aussieweb.com.au/email.aspx?id=1194181
RE: double-circular-arc gear generator software
I've only just realised that the DCA gear profile is not a Cycloidal profile.
Ron Volmershausen
Brunkerville Engineering
Newcastle Australia
http://www.aussieweb.com.au/email.aspx?id=1194181
RE: double-circular-arc gear generator software
I have several papers on double circular arc gears, I was just looking for additional input and experience, and also the software, I will check out what you recommended.
China is head over heels in love with double circualr arc gearing, and most of the papers on the subject are in Chinese as a result. The West seems to have chosen to ignore the benefits of DCA gears over involute for some reason. Can anyone offer as suggestion as to why that may be?
RE: double-circular-arc gear generator software
One interesting link is here:
http://www.zakgear.com/WN.html
RE: double-circular-arc gear generator software
Thanks for your link.
RE: double-circular-arc gear generator software
One paper I recommend is:
FUNDAMENTAL DEVELOPMENT OF HYPOCYCLOIDAL GEAR TRANSMISSIONS
by Park
ht
In chapter 4 these kinds of gears and their history/development is covered in detail. Though this paper deals with a slightly different application than mine, it still has many informative sources.
My application is a ring gear/pinion with a 2:1 ratio. Double or triple CA gears seem to offer greater strength in this application than involute gear tooth profiles could provide. If anyone has a gear tooth design to suggest that exceeds DCA or TCA gears, please post some info.
RE: double-circular-arc gear generator software
RE: double-circular-arc gear generator software
RE: double-circular-arc gear generator software
Some of the things seem obvious even for a "not a gear" expert like me: You would have to use helical gearing to improve contact ratio, the tooling would be expensive - different cutters for gear and pinion - and these gears are very sensitive to axial misalignment.
RE: double-circular-arc gear generator software
And I have also found that modified forms of circular arc gear tooth profiles are not as sensitive to axial misalignment as was initially thought. As well, many gearing applications have very accurate machining and tolerances, and misalignments are few, or very small.
RE: double-circular-arc gear generator software
You can find diagrams of this in the paper I last referenced.
RE: double-circular-arc gear generator software
RE: double-circular-arc gear generator software
They do sound promising. Thanks for
calling these to our attention.
RE: double-circular-arc gear generator software
By the way - the link posted by Clyde38 is probably the best what one can find about the topic and it should be sufficient to calculate the geometry. Litvin is good...
RE: double-circular-arc gear generator software
Lets say a double circular arc gear is mounted via hydrodynamic bearings. Do the subsequent variations in center distances that come with using that type of bearing preclude the use of DCA gears in that application?
RE: double-circular-arc gear generator software
http://www.zakgear.com/Gallery.html
This URL also has some relevant animations that show the contact point of DCA gears is not an ellipse as so many have claimed in the past, which results in a much higher contact area under loads.
RE: double-circular-arc gear generator software
what is the accuracy req'd. equivalent to the AGMA std.
One question was asked, what type of machines & tools are req'd to manufacture. shaping & hobbing may or may not be an issue.
is Grinding or honing with the current machines possible.
Is China & Russia tooled for such designed.
I never seen no less Mfg such gears in the USA
Mfgenggear
RE: double-circular-arc gear generator software
@mfgenggear: no offense, but I am having trouble discerning your comments. The accuracy requirement on my end is whatever will work in the chosen application. I am planning on using hydrodynamic bearings, and want to insure that any subsequent center-to-center deltas or errors are tolerable by the chosen circular arc gear.
I am aware that these types of gears are mostly made in Russia and China, and not in the U.S. That is one of the reasons I am here seeking information from people in the industry. Often a design may be rejected due to politics or the "not invented here" syndrome, and I do not want to overlook what may be a practical, superior alternative to standard involute tooth profile gears for those reasons.