topic Re: Ideas or examples needed to draw helical rotor in Inventor Forum

Ideas or examples needed to draw helical rotor

Dhegderx — Mon, 08 Aug 2022 06:58:46 GMT

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

Re: Ideas or examples needed to draw helical rotor

blandb — Mon, 08 Aug 2022 13:21:11 GMT

What version are you running?

Re: Ideas or examples needed to draw helical rotor

blandb — Mon, 08 Aug 2022 13:31:47 GMT

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

Re: Ideas or examples needed to draw helical rotor

Frederick_Law — Mon, 08 Aug 2022 14:35:31 GMT

Draw is easy.

Draw correctly is not.

Re: Ideas or examples needed to draw helical rotor

JonathanKruger — Mon, 08 Aug 2022 21:05:59 GMT

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.

Re: Ideas or examples needed to draw helical rotor

johnsonshiue — Mon, 08 Aug 2022 21:07:37 GMT

Hi Folks,

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

Many thanks!

Re: Ideas or examples needed to draw helical rotor

Dhegderx — Mon, 08 Aug 2022 23:36:50 GMT

Inventor 2023

Re: Ideas or examples needed to draw helical rotor

SBix26 — Tue, 09 Aug 2022 02:40:09 GMT

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.

Sam B

Inventor Pro 2023.1 | Windows 10 Home 21H2

Re: Ideas or examples needed to draw helical rotor

Dhegderx — Tue, 09 Aug 2022 02:54:28 GMT

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

Re: Ideas or examples needed to draw helical rotor

SBix26 — Tue, 09 Aug 2022 11:24:39 GMT

@Dhegderx wrote:

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

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...

Sam B

Inventor Pro 2023.1 | Windows 10 Home 21H2

Re: Ideas or examples needed to draw helical rotor

Frederick_Law — Tue, 09 Aug 2022 15:53:21 GMT

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.