SPRING LIFE CALCULATION

[bbaskar-2]

Is there any worked examples in calculating the spring life.

[LucMeekes]

Is this related to biology (the emergence of new life by young born animals and growing plants in the spring season)?

Or are you dealing with those (usually metal) wound shapes that can be pressed and stretched and you wonder how many times one such part survives pressing or stretching?

Luc

[-MFra-]

In the first case, it would be inappropriate to make the request in the mechanical section. Do not you think?

The application refers to the average life of an object: the elastic spring.

The average life of an object is linked to the reliability of the object itself.

And then you must refer to the reliability theory.

[LucMeekes]

Maybe it's more a matter of (mechanical) fatigue.

[LucMeekes]

Might as well that 'life' is understood as the amount of times a given spring will jump up from the floor once dropped from a certain height...

Who knows... let's wait for the OP to respond.

[bbaskar-2]

Dear sir,

SPRING LIFE CALCULATION

Is there any worked examples in calculating the mechanical spring life (energy storing device)

Eg: springs in computer keyboard's

springs in writing pen.

[VladimirN]

Please find a PDF document in attachment.

[-MFra-]

Hi VladimirN.

He does not look for a software for the design of springs. He wants to know how much time passes before a spring breaks, that is, the average life of a spring of a certain type obviously. To know this, we do a statistical, as you know. You determines the average frequency of breakage and trying to define the distribution. If the distribution is similar to that of Weibull for example, with the statistical data, they are obtained the two coefficients of the distribution.

[mjenkins]

I like to use the software MITCalc.  It can select from many types of springs.  Then based on user input can calculate the number of cycles for you.

It can even generate the model and drawing for you after you push a button.

There is a trial available for Pro Engineer:

http://www.cogras.cz/Products/MITCalc

[mjenkins]

I did a demo of this one and it is pretty good too.

It also does barrel springs which MITCalc does not.

However it does not generate the model for you:

Spring Calculator Professional

https://www.ist.org.uk/software/spring-calculator-professional-features/

[DenisJaunin]

Hello

For information if it can serve you, unfortunately it's in French.

See Chapter 8.

Kind regards.

Denis

https://books.google.ch/books?id=G9ejj_S-sZUC&pg=PA21&lpg=PA21&dq=calcul+de+la+dur%C3%A9e+de+vie+d'un+ressort&source=bl&ots=tuPHpZ6jxd&sig=ffzEg2JnaTituEUz4DOl9h_-i7E&hl=fr&sa=X&ved=0ahUKEwi80Z-Gru_SAhXPOSwKHQB4DBo4ChDoAQhAMAU#v=onepage&q=calcul%20de%20la%20dur%C3%A9e%20de%20vie%20d'un%20ressort&f=f...

http://www.ressorts-sodemann.fr/faq-wiki-ressorts/ressorts-de-compression/combien-de-cycles-un-ressort-de-compression-peut-il-supporter

https://www.nde-ed.org/EducationResources/CommunityCollege/Materials/Mechanical/S-NFatigue.htm

http://www.amesweb.info/MechanicalSprings/CompressionSpringFatigueDesign.aspx

[bbaskar-2]

Dear sir,

           Tanks for ur Valuable reply..

[bbaskar-2]

Dear sir,

              I want to know the life of mechanical spring in computer keyboard the assume the force to hit the spring.

[-MFra-]

The only chance you have, is to ask computer manufacturers.

[Fred_Kohlhepp]

There are a lot of calculators out there, so implementing one in Mathcad is certainly possible.  To estimate the fatigue life of a particular spring you would need to know details of the spring (material, dimensions, number of coils), and details of the installation (installed length, compressed length, etc.

Generally keyboard designers target a specific life; 50 million key presses seems to be a common goal.