Hello
I have to model spline parts and the problem is that I never find the same calculation formula depending on the sources... I started with my "industrial designer's guide" but it turned out to be incomplete as soon as you changed the standard... In this case, DIN 5480. So does anyone have the suite of formulas that goes well? Thank you in advance.
See this link
https://www.eassistant.eu/fr/eassistant/liaison-arbre-moyeu/cannelures-a-flancs-developpants.html
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Thanks gt22, but it's a link to a paid software, which I've already visited by the way... I don't come to you without having done some research first. To be more specific about my problem, I have the physical part, but I can't measure it precisely. So I model it by calculation, knowing that I still have the outer and inner diameter of the shaft. But when I apply the formulas, the sketch is wrong at the level of the tooth head.
Hello
Look at ICI, there is the same link as given by gt22 but also a link to the formulas of the circle involute.
Kind regards
Thank you for your answers!! So developing it, no worries, I understood how to draw it... On the other hand, when I follow the given formulas, I don't get all the dimensions of the physical part: the diameters are good after calculation and physical verification, but the width of the tooth head is too narrow on the drawing... on the caliper I have approximately 4.4 and on the sketch I have 2 and bananas... and I don't understand why...
What is the exact need?
It's rare that we have to model this kind of thing exactly, a note is much more accurate.
A quick Google search and the term "DIN 5480 Splines" leads to this, e.g.: www.tandwiel.info.
You say you've done some research, ok, what did you find and what are you missing?
4.4 measured and 2 and bananas by calculation, yes but:
- For which module?
- for what number of teeth?
- What are the values of the diameters that you measured?
Kind regards
So stefbeno:
I found the same site as you. And for what I'm missing I'll try to be clear:
I have to model a fluted tree, without any ref., and therefore to measure it's cotton. I can measure the diameter of the head, the foot and that's it. I can make an approximation for the rest. When I go through the formulas to redefine the part (24 teeth, module 3, nominal diameter 78) I don't get in drawing what I have in physics. By going through another module, it's not better and by changing the pressure angle either. What I would like to know is where did I make a mistake, if I made a mistake, or is there a subtlety...?
D.Roger:
So module 3, 24 teeth, head diameter 77.4, foot diameter 70.8.
So if we take a nominal diameter of 78 in DIN 5480, we find the diameter measurements. On the other hand, for the thickness of the head of the teeth, we are not at all good...
I'd actually like to understand how the person who produced this coin comes across ~4.4 at the head of the tooth, or if he took this dimension at random, or if it's me who makes a mistake...
Thank you in any case for looking into my problem.
I guess the ref to DIN5480 is safe.
The only thing that seems variable is a possible deportation.
Going from 4.4 to ~2 is a big gap.
That's a ratio of about 2:1
Look at the Altitech library
On our favorite browser
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I'm not sure about the DIN5480 standard, could you put us a picture of the end of your piece?
Kind regards
sorry for the delay... So D.Roger, some photos of the end?! b I'm not sure I understand...
So according to my research, they would be flutes of proprietary dimensions... So unless I measure them precisely, I'll never know how to draw them... Thank you for your help in any case.
Front photos if you prefer, something like this:
That we see what the grooves look like.
Kind regards
If it's proprietary (they really wanted to be ch##r to reinvent it), and you need to reproduce, as it's a tree, it's easy to do a 3D scan, you just have to find the right provider.
Stefbeno: Would it be so surprising? That's a real question...
D.Roger:
yes that's standard ?????
gt22: All right, so tell me how you draw it to the standard you want and have it look that way in the end? Because that's my question... Following the standards, I have a more pronounced gap between each tooth and therefore, a tooth head that is too narrow... I went to see a machinist, who confirmed to me, according to him of course, that it is out of the ordinary.
Unfortunately I think you don't have 36 solutions:
- either it's an exotic standard and you have to find it but given your measurement problem, it's almost mission impossible unless there is a masterful stroke of luck;
- or it is pure ownership as you mentioned and you have to be able to measure in order to reproduce.
To measure, since you are not equipped, you "only" have to find a service provider equipped with tridim, laser, profile projector (although given the thickness of the part it is not easy, but there is a way to do things by making a thin impression with wax for example).
To manufacture, the machinist will make a good figure when you present him with a plan that details the non-standard tooth.
Stefbeno: You substantiate what I assume from the beginning... But insofar as (no pun intended) I'm a very young designer, I was hoping for a lack of knowledge or misunderstanding on my part... Thank you all for your answers.