Free body diagram of bearings(FEA)

[stress1987]

Experts,

I have some doubts in doing a FEA analysis of housing with bevel gears.I hav taken the housing along with gears n bearings and applied the resulting radial loads on the bearings as two components one as the horizontal and the other vertical and the axial load of the bevel gear directly on the housing.I have 2 bearings each on the bevel gear.I am facing diffuclty in judgin the horizontal and vertical radial reaction directions which need to b applied on the bearings.(Note this radial reactions r got from some program).I hav attached a picture for reference. My doubt is whether the bearing reaction at location 2 & 3 will be in same or opposite reaction. My guess is it should be in opposite.I would also like to know the direction of reactions at 1 & 4.

 

[leisure17]

Take one of the bearings away and see which way it wants to lift/drop. It depends on the rotaion. Also with bevels you have a seperating and axial force.
Have a look in a bearing manufacturers catalog, they use to have all that info.

 

[rb1957]

see also FEA forum ...

btw, don't multi-post

 

[tbuelna]

stress1987,

If the gears are spiral bevels the direction of axial thrust forces for each gear depend upon which gear is the driver or being driven, which gear has LH or RH spiral, and which direction each gear rotates.

Good luck.
Terry

 

[zekeman]

The simple answer to your dilemma is once you get the force vector on one bevel gear, it is quite obvious ( Newton's law of action and reaction) that the force vector on the contacting gear is equal and opposite as you surmised.

The main problem is getting that force vector and if you can state the type of bevel gear you are using maybe we can give additional help in getting the values.

 

[stress1987]

@leisure17-Both the bevel gears rotate in the same direction.
@rb1957-sorry for multiposting
@tbulena-the gears are bevel and rotate in same direction.
@Zekeman-Its a Straight bevel gear