Positioning spring to lift ramp

[grahamhoward]

Trying to lift a ramp of a lowloader with a spring. To get a spring mounted on a straight line from behind the ramp in a upright poistion. To a point straight below it on the frame of the lowloader . Which is determed by the strength of the spring compaired to the weight of the ramp.It also doesn't give you much leaverage in the down poistion. WOULD by putting the bottom point to mount the spring staight under the ramp piviot point(main pin). Then making a arm going at say 45deg up past the bottom of the ramp than 45deg upright with ramp. Than put the spring in there. When the ramp was being lowered the spring in turn would go further apart from ramp. Would that give the spring more leavage over ramp. Or is it tranfer back to bottom point.

 

[desertfox]

HI grahamhoward

How big is this ramp and whats its mass.
You may be better of using torsion springs placed at the ramp hinge.
if you can provide some further information I maybe able to help.


regards desertfox

 

[grahamhoward]

To Desertfox,
Not real sure how to reply to you hope this is right. Im thinking the springs your talking about wont be heavy enough . Already have put those into a scenario. WHich would be a lot neater and easier to do. The ramps are 3.2 mt long. weighing about 350kg. Im basically looking for a fair bit of purchase in the down position lifting that sort of weight from one end. Thanks Graham

 

[desertfox]

Hi grahamhoward

Thanks for your response.

With a ramp of this size I would forget springs and suggest that you consider either hydraulic or pneumatic rams or even a pulley system with a counter balance weight.

regards desertfox

 

[grahamhoward]

MR Desertfox

Good morning. Cold this day. Yes that will be the next move if nobody has any experence with the idea. If I get better push with the dog leg idea to get the spring lower(Furter apart from ramp to spring)in the down postion. Than close in the upright where I don't need as much lift. The hydric cause other problems where the little electic motor is in the road dust(bull dust). Also the battery is beening belted to bit.A failure there is not good when you are in the middle of nowhere. Springs won't fail. The other way is to use a air bag. Used in the same way as the sping or a ram. And run it of the air surply of the truck. But I have another problem in stablizing the air bag from flopping to a side. Making a cage for the bag has a problem in getting the bag in and out. Air rams won't work due to small surface and only 100psi supply from truck. Air bags BEENING 9 OR14 TON LIFTING(BUT CAGE). Spring beening maintance free.

 

[boo1]

Consider DFoxes pully idea. For the spring to offer any real assistance the extended length will require considerable effort to fully open the ramp.

 

[grahamhoward]

Thanks boo1
The pully idea. Got a thru problem which a couter weight. the idea is to not carry any more weight than nessary. Where you would house the weight bearning in mind you have wheels and axles for 5 meters in front of ramp. The other problem is how you would put a pully high enough to work and load by driving over the pully and ropes.Remenbering the rope and pully will be tentioned because the ramp is in down poistion to load.
Does anyone know if i can draw a picture on here
I need to Know if anyone has thoughts on mounting the spring so it's working at a differant angle in the down poistion to the up poistion by useing a L sharped piviot on the bottom mount.
Thank you all. It great to kick ideas with all.
Throw your idea in. Graham

 

[desertfox]

Hi grahamhoward


Unfortunately springs aren't maintenance free the have to be protected in harsh enviroments ie to prevent corrosion also springs can fail due to over load etc.
You can post images in here using the "process TMGL" button at the bottom of the message box, it would be useful to see a drawing or diagram of your problem.

regards desertfox

 

[swBausch]

What is a lowloader? I don't think you are talking about a liftgate, are you? Liftgates use a wound spring and that spring might be a great place for you to start.

If you know what I am speaking of, go look at a liftgate or two.


My best guess is you are speaking of a 'beavertail' ramp for a lowboy trailer. Take a good hard look at the springs used on liftgates and see if that's a spring you could use.