Axis definition for rotating gears

vivjk94 · December 1, 2020, 06:54

hello, i have modelled a 6 tooth spur gear for my gear pump. I will be setting the gears to rotate at a certain rpm and need to make sure the rotor rotates with no obstruction to casing. If i use axis definition option as rotating between 'Two points', what should my rotation axis values( x1, y1, z1 and x2 , y2, z2) be?
i would like to know from where i can get this data as well.

Thank you in advance.

urosgrivc · December 1, 2020, 07:04

isn't it obvious ( x1, y1, z1 and x2, y2, z2)

XYZ 1 this is the start point of the axis
XYZ 2 this is the endpoint of the axis

whatever you will rotate, will rotate around this axis.
Only you know the answer to where your axis is, we don't, unless you provide some more data

there is a lot of ways how to get these values, one of them is, you are able to get the XYZ values by
creating two coordinate systems one on each end of your gear.
You are able to get them from design modeler, meshing software or cfxpre
maybe you can even get them from drawings or whatever basically it depends on what you have access to.

a far bigger problem than setting up the axis will be the mesh if you want to model this with two gears which overlap

vivjk94 · December 1, 2020, 11:11

thanks for the answer. i will try to find a way for the gear problem.

Gert-Jan · December 1, 2020, 16:02

What might be easier is if you define a local coordinate on a round gear surface which is in the center of rotation. Then, upon defining the rotation, use this local coordinate. So no need to find the coordinates by hand

vivjk94 · December 1, 2020, 20:41

Thanks, That helps a lot.

December 1, 2020, 06:54	Axis definition for rotating gears	#1
vivjk94 Member Vivek MJ Join Date: Oct 2020 Location: India Posts: 53 Rep Power: 5	hello, i have modelled a 6 tooth spur gear for my gear pump. I will be setting the gears to rotate at a certain rpm and need to make sure the rotor rotates with no obstruction to casing. If i use axis definition option as rotating between 'Two points', what should my rotation axis values( x1, y1, z1 and x2 , y2, z2) be? i would like to know from where i can get this data as well. Thank you in advance. Last edited by vivjk94; December 1, 2020 at 06:55. Reason: axis definition, cfx pre, gear geometry

December 1, 2020, 07:04		#2
urosgrivc Senior Member urosgrivc Join Date: Dec 2015 Location: Slovenija Posts: 365 Rep Power: 11	isn't it obvious ( x1, y1, z1 and x2, y2, z2) XYZ 1 this is the start point of the axis XYZ 2 this is the endpoint of the axis whatever you will rotate, will rotate around this axis. Only you know the answer to where your axis is, we don't, unless you provide some more data there is a lot of ways how to get these values, one of them is, you are able to get the XYZ values by creating two coordinate systems one on each end of your gear. You are able to get them from design modeler, meshing software or cfxpre maybe you can even get them from drawings or whatever basically it depends on what you have access to. a far bigger problem than setting up the axis will be the mesh if you want to model this with two gears which overlap vivjk94 and aero_head like this. Last edited by urosgrivc; December 2, 2020 at 00:57.

December 1, 2020, 16:02		#4
Gert-Jan Senior Member Gert-Jan Join Date: Oct 2012 Location: Europe Posts: 1,828 Rep Power: 27	What might be easier is if you define a local coordinate on a round gear surface which is in the center of rotation. Then, upon defining the rotation, use this local coordinate. So no need to find the coordinates by hand vivjk94 likes this.

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December 1, 2020, 11:11		#3
vivjk94 Member Vivek MJ Join Date: Oct 2020 Location: India Posts: 53 Rep Power: 5	thanks for the answer. i will try to find a way for the gear problem.

December 1, 2020, 20:41		#5
vivjk94 Member Vivek MJ Join Date: Oct 2020 Location: India Posts: 53 Rep Power: 5	Thanks, That helps a lot.