Ideas or examples needed to draw helical rotor

[Dhegderx]

  

Hi Experts,

The above part is from a progressive cavity pump and I am struggling to draw it. The total length of the part is 1830mm, the length and diameter of the hub is 143.50mm and 120mm respectively. The diameter of the coil is roughly around 73 mm on average  and oscillates between 71- 78mm.

Can anyone please guide or model something like this so that i can visualize how to draw this.

Thanks

[blandb]

What version are you running?

[blandb · Accepted solution]

Attached is a '22 very quick example. I imagine there will be others as well.

[Frederick_Law]

Draw is easy.

Draw correctly is not.

[JonathanKruger]

I don't know why but I imagined your answer being said by Yoda which made me me laugh, but I assume there is some "design" that you need to understand in order to draw this correctly?

I would be interested to understand but have no experience with these kind of pump designs.

[johnsonshiue]

Hi Folks,

I could be wrong but I suspect this is something Solid Sweep can help.

Many thanks!

[Dhegderx]

Inventor 2023

[SBix26 · Accepted solution]

Here's my attempt with Inventor 2023.  I don't have all the parameters, of course, but these can be adjusted.  The diameter of the helical section varies between 78mm and 71mm with each turn-- not sure if that's what you meant or not, but I achieved that with a Loft over one pitch of the screw, then patterned that one.

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Sam B

Inventor Pro 2023.1 | Windows 10 Home 21H2

[Dhegderx]

Excellent more  precise  and exactly what I was looking for thanks.

[SBix26]

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@Dhegderx wrote:

Excellent more  precise  and exactly what I was looking for thanks.

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More precise, perhaps; but a Loft feature is rarely well enough defined to use for a machined part.  If you need this for appearance, or to make a drawing where the precise definition of the part is given by text, it may be adequate.  But it certainly is not sufficient as the definition for machining a precision part like this.  If such a model is needed, I have no good ideas at this point for how to create it...

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Sam B

Inventor Pro 2023.1 | Windows 10 Home 21H2

[Frederick_Law]

Talk like Yoda, I do.

Sometime

😂

Not knowing the application or mating part, it'll be difficult to make it correct.

Since OP said it's progressive pump, it'll have tight fit depends on medium it's pumping.

Some screw pump has increasing/decreasing pitch/diameter.

If this is a good sample, 3D scan it.

If its worn out and repaired, good luck.