A quick lesson on Independant suspension:

mattslope · 03-26-2005, 01:23 PM

I will attempt to demonstrate how suspension works. Please contact me if you need further explanation.

The above is a simple diagram of half of a solid rear axle. The tire is all black, the spring is on the axle tube and the third member is cut in half for the pic.

When cornering, the road and tire exchange force through friction; in this case the tire is being acted upon towards the inside of the axle.

The weight of the vehicle (sprung weight) is acting upon the axle in a downward direction. The weight of all components not placed over the spring is called unsprung weight. The point where the spring contacts the axle is the fulcrum (picture the middle of a seesaw).

Because force is being applied to the bottom of the tire (which is now acting as a lever) and the fulcrum point is close to the tire, the other tire is being lifted from the road.

mattslope · 03-26-2005, 01:29 PM

The above is a crude example of an independant suspension (in this case a rear suspension). The tire is black, with the spring (indicated with red arrow to show gravitational force of vehicle), flex points and half of third member.

Again, when the road and tire act upon eachother in friction, the tire is pushed inward.

The fulcrum remains at the same point (the spring), making the tire which is acting as a lever push the axle upward.

Because the axle has seperated flex points, the other tire is not affected. The third member is connected to the car and does not move with the suspension.

crazybassmonkey · 07-29-2005, 05:58 PM

mmmm, swing axle suspention and half wishbone with macperson struts.

i've got an essay to write on all that sometime this month!

its a good simplification of something quite complex.

mattslope · 08-01-2005, 11:44 AM

Quote:

Originally Posted by crazybassmonkey

mmmm, swing axle suspention and half wishbone with macperson struts.

i've got an essay to write on all that sometime this month!

its a good simplification of something quite complex.

Pictures.

**redbaron** · 09-26-2005, 06:16 PM

If you vote "no, this was not helpful" please post your reasons and or questions, so that someone can explain this to you in more depth so that you can understand it better.

lateforwork · 04-25-2006, 11:37 AM

Not for me so much, but you could make a special "....For Dummies" Edition. Mad money!!

mattslope · 04-25-2006, 06:39 PM

Quote:

Originally Posted by lateforwork

Not for me so much, but you could make a special "....For Dummies" Edition. Mad money!!

I think you mean that the illustrations were too complex for you. I can't simplify it any further. Can someone else step in?

**jump5fan** · 04-26-2006, 07:38 AM

http://auto.howstuffworks.com/car-suspension.htm

mattslope · 04-26-2006, 03:08 PM

Quote:

Originally Posted by Jump5fan

http://auto.howstuffworks.com/car-suspension.htm

Good call. Clearly, the following quote is far less complex than a simple drawing:

Quote:

Rear Suspension - Independent Suspensions
If both the front and back suspensions are independent, then all of the wheels are mounted and sprung individually, resulting in what car advertisements tout as "four-wheel independent suspension." Any suspension that can be used on the front of the car can be used on the rear, and versions of the front independent systems described in the previous section can be found on the rear axles. Of course, in the rear of the car, the steering rack -- the assembly that includes the pinion gear wheel and enables the wheels to turn from side to side -- is absent. This means that rear independent suspensions can be simplified versions of front ones, although the basic principles remain the same.

JerryLove · 02-06-2008, 08:46 AM

My problem is that, in attempting to offer a conclusion, the explantion is too simple to support it.

A tire does not life from the road because of an independant vs solid-axle suspension... if that were the case then independantly suspended wheels would never leave the road.

During turns, the vehicle's body wants to lean or "roll" to the outside of the turn due to centrifugal force. This can cause the inside wheels to have a tendency to lift from the ground resulting in less than optimal traction. An anti-roll bar (also called anti-sway bars) connects the left and right suspension components with a stiffened bar. This bar resists the body's attempts to let the car lean to either side helping to leave all 4 wheels on the ground.

The real disadvantage of a solid-axle is that changes in road elevation (bumps) hitting only one tire translate to the whole car... it makes for a stiffer ride. For this same reason, it can lower traction (with bumps being transmitted to uninvolved wheels), but it's less expensive and simpler.

mattslope · 02-10-2008, 12:21 AM

Quote:

Originally Posted by JerryLove

My problem is that, in attempting to offer a conclusion, the explantion is too simple to support it.

A tire does not life from the road because of an independant vs solid-axle suspension... if that were the case then independantly suspended wheels would never leave the road.

During turns, the vehicle's body wants to lean or "roll" to the outside of the turn due to centrifugal force. This can cause the inside wheels to have a tendency to lift from the ground resulting in less than optimal traction. An anti-roll bar (also called anti-sway bars) connects the left and right suspension components with a stiffened bar. This bar resists the body's attempts to let the car lean to either side helping to leave all 4 wheels on the ground.

The real disadvantage of a solid-axle is that changes in road elevation (bumps) hitting only one tire translate to the whole car... it makes for a stiffer ride. For this same reason, it can lower traction (with bumps being transmitted to uninvolved wheels), but it's less expensive and simpler.

I'll respond to you in 3 years.