Define loads/Engine mount
Define loads/Engine mount
(OP)
Hello,
I have some probleme to determine the loads acting on an engine mount.
I have an engine mount which bears a 91 kg engine with 4 attachment point,at each corner of the engine. I am studying the lower attachment point of this mount. The engine is in cantilever.
From my point of view I have define as loads:
- The engine's weight
- The moment due to the cantilever
- A starting torque
- And a compression loads because if I look the engine on one side we can see the two attachment points and the engine's centre of gravity between the two points (on the middle line). If there weren't the attachment point, then the engine would rotate around its center of gravity, consequently there is a couple, and on each attachment point we have: compression load for the lower point and tractive effort for the upper point.
Do you think my argument is good?
Thanks for your help,
Mickaël
I have some probleme to determine the loads acting on an engine mount.
I have an engine mount which bears a 91 kg engine with 4 attachment point,at each corner of the engine. I am studying the lower attachment point of this mount. The engine is in cantilever.
From my point of view I have define as loads:
- The engine's weight
- The moment due to the cantilever
- A starting torque
- And a compression loads because if I look the engine on one side we can see the two attachment points and the engine's centre of gravity between the two points (on the middle line). If there weren't the attachment point, then the engine would rotate around its center of gravity, consequently there is a couple, and on each attachment point we have: compression load for the lower point and tractive effort for the upper point.
Do you think my argument is good?
Thanks for your help,
Mickaël





RE: Define loads/Engine mount
How is the motor coupled to its load?
Cheers
Greg Locock
Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: Define loads/Engine mount
The frame is stationnary for this analysis. the engine is attaches to the engine using tubes with rubber shock mount.
you can have an idea with this picture:
http://www.cozygirrrl.com/images/parts/conical.gif
Thank you,
Regards
Mickaël
RE: Define loads/Engine mount
Cheers
Greg Locock
Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: Define loads/Engine mount
RE: Define loads/Engine mount
as greg succinctly posted "you have other loads" ... you've got a good enough handle on the weight of the engine, but you have to consider the engine output (torque) has to be reacted at the motor, plus i think you need to think about the dynamic forces involved (due to all the bits and pieces whirling about) and how about the imbalance within the engine (as different cyclinders fire) ...
you also need to consider the fact that you've got two different styles of mounts. two mounts are supported by a tripod of struts, good for reacting load in pretty much any direction; but two mounts have only a single strut, good only for axial load (as these struts react load in one direction they induce loads in the other two directions, and these induced loads have to be reacted at the other mount).
RE: Define loads/Engine mount