Calculating Bearing Load for Linear Slides: Equation and Examples

[tomsdubs]

Homework Statement

Need to know the bearing load for a linear slide I'm working on, two spaced bearings with an extended load off the end of the slide.

Homework Equations

What equation do I need to apply? What examples are out there?

The Attempt at a Solution

 

[SteamKing]

You need to apply the equations of static equilibrium to determine R1 and R2.

 

[tomsdubs]

I'm still not sure how to apply, I can't find any relevant examples. The two distances are 1.5m and 1m, bearing spread and mass extended.

 

[tomsdubs]

R1 = 1/2.5*(30*1) = 12kg
R2 = 1/2.5*((30*2.5)+(30*1)) = 42kg

This is how I've done it, if anyone can give me some guidance that'd be great.

 

[beamsandthangs]

Use equilibrium equations

Lets assume both reactions (R1, R2) are facing upwards.

Now we do the sum of forces in the Y direction=0, where upwards is positive.

So, Sum of Fy=0: R1 + R2 - 30=0

Now let's take the sum of the moments at point 1 equal to zero, where anti-clockwise is positive.

So, Sum of M1=0: (1.5)(R2) -(2.5)(30)= 0
(1.5)(R2)=75
R2= 75/1.5
R2=50kg

Substituting in the 1st equation:

R1 + 50 -30 =0
R1 +20=0
R1= -20kg

So your reactions R1 and R2 are -20kg, 50kg respectively.

 

[tomsdubs]

Thanks I understand now, appreciate your help.