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gas spring sizing

  • Thread starter Thread starter Luciano Ricci
  • Start date Start date

Luciano Ricci

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Hello everyone,
I'm trying to size a gas spring on a carter door for an automatic machine. the weight is about 13kg. the spring is mounted on the right side with an inclination of about 7° upwards. the problem is that I am late with the project and it is all day that I look for a formula that can come back useful since unfortunately I am a little rusty. If anyone can tell me where to find one.

Thank you very much
 

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not to start in fourth... presented.

just a search with google and take a iter; almost all have formulas in the catalogs on how and the type of spring to use.
use
I've been able to use this lately. http://www.stabilus.it; the translation in Italian lets you want, where you read standard gas spring program refers to technical pdf
 
Luciano Ricci said:
Hello everyone,
I'm trying to size a gas spring on a carter door for an automatic machine. the weight is about 13kg. the spring is mounted on the right side with an inclination of about 7° upwards. the problem is that I am late with the project and it is all day that I look for a formula that can come back useful since unfortunately I am a little rusty. If anyone can tell me where to find one.

Thank you very much
Click to expand...
Good morning.
I can suggest you contact the lineartech (stabilus retailers). they can support any demand in terms of size and especially stock availability. failure of the second condition could lead you to further delay on the project.
as a recommendation considers the forces to be applied in the open/closed conditions of the crew since, if manual, this should not be exaggerated.
 
search on the forum that posted the schematic and calculation formulas, discussion already dealt
 
would be fine:
- learn to search on the forum
- learn how to download the catalogues of gas springs and read the instructions for sizing and choice
- apply some formula
nb: the calculation is for the case subjected by gluke68 that could post here the image of the requestafter that I resume the discussion that I did time ago re-posting the material and formulas. in the end the case to be analyzed is like the one placed at the first request but turned 180° and the weight force is turned of sign, the gas springs are put so sensibly so that the door remains also closed.

allego calculation formulas (to reason above)molle_gas_formule.webpgraph for fast sizing without special formulas since it is made for 90° opening, molle a gas_grafico90gradi_1.webpcalculation card for the case required in the specificmolle a gas_calcolo_1.webpI would say that then you take the catalog and you experience the race and you choose the suitable force. be careful that the force changes slightly if the gas spring piston is mounted in one way or another.
 
hi to all of the forum,
therefore reading the formula of mechanicsmg:

I'm sorry.

I cannot explain that "cos.beta" in the terms of the left, that is, I would write:

♪

in practice "moment soft = moment hatch"
So I think the soft moment is independent of the corner where the door is located, but if I'm wrong, correct me.

Thank you.
 
matricola2 said:
hi to all of the forum,
therefore reading the formula of mechanicsmg:

I'm sorry.

I cannot explain that "cos.beta" in the terms of the left, that is, I would write:

♪

in practice "moment soft = moment hatch"
So I think the soft moment is independent of the corner where the door is located, but if I'm wrong, correct me.

Thank you.
Click to expand...
the springs must push with guarantee in the maximum open position, as long as the door is not closed alone.
 
I'm not even sure the spring is installed in the right direction.
I think it should have inverted attacks

Thank you
 
Good morning.
What would change if I had to use a gas spring to raise or lower a seat back?
I explain better, for example, the weight of everything (man+schienale) would be concentrated in the center of gravity g that is far enough from the point of incernieramento and with the almost horizontal piston.
as soon as I can try to make a scheme/drawn.
Hello wagliu!
 
Good morning, everyone.
as promised I attached a scheme of my problem.
before switching to formulas I just wanted to understand if the distances were those taken in the right direction, in particular to the terms on reported as bf and bc distances from the point of rotation to the ends of the spring.
I have not understood well but bf is taken as direction orthogonally to force (to calculate the moment) while bc taken parallel to the object?

Thank you to anyone who wants to waste some time on Sunday morning to clarify these doubts?
Thank you.
 

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meccanicamg said:
would be fine:
- learn to search on the forum
- learn how to download the catalogues of gas springs and read the instructions for sizing and choice
- apply some formula
nb: the calculation is for the case subjected by gluke68 that could post here the image of the requestafter that I resume the discussion that I did time ago re-posting the material and formulas. in the end the case to be analyzed is like the one placed at the first request but turned 180° and the weight force is turned of sign, the gas springs are put so sensibly so that the door remains also closed.

allego calculation formulas (to reason above)View attachment 33141graph for fast sizing without special formulas since it is made for 90° opening, View attachment 33140calculation card for the case required in the specificView attachment 33139I would say that then you take the catalog and you experience the race and you choose the suitable force. be careful that the force changes slightly if the gas spring piston is mounted in one way or another.
Click to expand...
Have a little clarification.
bb distance of the object to be lifted from the center of rotation.
bc extreme distance spring from the center of rotation
bf distance other extreme spring from rotation center

Is that correct?
In the same way as p and f, the formula in question is obtained and similarly the fc report.

I have a similar problem, only that instead of raising a door dvorei use a piston to recline a seat and my gas spring is practically horizontal so , even alpha=0°,? ? ? ?
 

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If the cylinder works completely different compared to the scheme I almost certainly believe that the formulas are no longer good because the pattern is a simplification and linearization of the equations.
 
meccanicamg said:
If the cylinder works completely different compared to the scheme I almost certainly believe that the formulas are no longer good because the pattern is a simplification and linearization of the equations.
Click to expand...
I imagined it; was at least to understand if the parameters of the problem were the same in terms of distance compared to the axis of rotation, baricentro ect ect.
Can you recommend some catalog where a part is indicated on the dimensioning?
I'd hardly find anything on reclining seats.
 
I think it's not a matter of seats, you have to know how to do the cinematic analysis and break forces and arms.
 
meccanicamg said:
I think it's not a matter of seats, you have to know how to do the cinematic analysis and break forces and arms.
Click to expand...
in practice the point c is the rotation point of the seat from the rest position with fi = 114° and in a reclined position at 139°. the only forces at stake are the f force of the piston and the p strength of the seat weight.
Maybe I try as soon as I have a little time, choosing as a pole the center of rotation; the element between a and there is a reinforcement element that supports the seat in practice and should be considered as one with the same
 
meccanicamg said:
would be fine:
- learn to search on the forum
- learn how to download the catalogues of gas springs and read the instructions for sizing and choice
- apply some formula
nb: the calculation is for the case subjected by gluke68 that could post here the image of the requestafter that I resume the discussion that I did time ago re-posting the material and formulas. in the end the case to be analyzed is like the one placed at the first request but turned 180° and the weight force is turned of sign, the gas springs are put so sensibly so that the door remains also closed.

allego calculation formulas (to reason above)View attachment 33141graph for fast sizing without special formulas since it is made for 90° opening,View attachment 33140calculation card for the case required in the specificView attachment 33139I would say that then you take the catalog and you experience the race and you choose the suitable force. be careful that the force changes slightly if the gas spring piston is mounted in one way or another.
Click to expand...
just for..... the spring is working in extension while closing the door the spring is working in compression.
 
meccanicamg said:
gas springs always push to stretch. all depends on the centers and do lightning.
Click to expand...
I do not understand the phrase "they always paint to stretch"; on diagrams I see compression and expansion phase (referred to the end of the stem)
 

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