What system could replace a spring? 3

[Martijn Roks]

Hello,

I am doing a internship and I am working on a device that has a spring to generate force, by pressing it downstairs and hold it in that position. When a release button is pushed then the spring goes back to it's normal form and releases the power.

Now I am looking for a few system that could replace the spring, because my boss wants get rid of the spring.

Has some one a idea that could replace a spring and still generate enough force?

hopefully someone can help me!

 

[IRstuff]

Interesting school that would ask you to replace something cheap and simple to make with something more expensive and more complicated; is the school named "Goldberg" by any chance?

springs can be made from a number of metals. magnets can be made from a number of metals. Magnet will need some sort of fixed and guaranteed separation, making the enclosure more complicated; magnets need to be attached with adhesive, making "destroyed and reused" more complicated. How does that simplify "destroyed and reused?"

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[MintJulep]

so it could be destroyed and reused.

The highlighted concepts are mutually exclusive.

Where is the "release button" in your sketch?

What is the purpose of this thing?

Engineers must work with quantifiable criteria. Thus far there are none stated.

Given what you have explained so far I would choose a spring.

 

[EdStainless]

Don't use magnets, expensive touchy to work with and hard to recycle.
What is the housing and button, plastic?
Have you looked at plastic spring elements. Maybe leaves in order to give you enough force.


= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

 

[BrianPetersen]

Look at the mechanism of a retractable ball-point pen - the kind where you press the button on the end to make the writing end poke out, then press it again to make it retract.

That mechanism contains ... a spring.

 

[LittleInch]

I agree. Sounds like a pen to me.

Screw mechanism instead?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[IRstuff]

I think EdStainless' suggestion to make a leaf spring would get you your needed spring-like behavior without the overt appearance of a spring.

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[BUGGAR]

I'm seeing a five cylinder revolver shooting five blanks. Or if the boss wants cheap, get a Saturday night special and don't load the sixth cylinder. Or surprise your boss by loading the sixth cylinder and asking for a raise for improving the product.

 

[IRstuff]

For sure, a 20% improvement in capabilities ought to get a raise.

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[GrouchyStressedTensePoor]

Agree with Ed,I would take a wild guess that the spring is "undesirable" because the rest of the assembly is plastic that is metled down and so they don't want to have to take it apart and remove the spring first. Using the same material to create a spring seems to solve that problem. Potentially the spring could even be integrated into one of the other parts as a flexure/snap fit style device.

GSTP

Graduate Mechanical Design Engineer
UK

 

[Artisi]

Google plastic spring.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[Jboggs]

I'm seeing a lot of responses here but no one is asking the key question - why does your boss object to a spring? I suspect he has had some bad experience with a spring and is trying to avoid a repeat. Find out more about his objections. What doesn't he like? Is he afraid of failure of the spring? Is it not repeatable enough? Is it too difficult to assemble? His objections could be many things.

Once you know more you will also know which direction to go. Right now you are just guessing at a solution that MIGHT make him happy.

 

[LL631]

Take a look at Compliant Mechanisms, this is essentially what GSTP has suggested :

https://www.youtube.com/watch?v=97t7Xj_iBv0.

You could combine parts 1,2 & 3 into a single molded component saving costs and will get bonus points from your school for being innovative.

 

[handleman]

no one is asking the key question

I asked that two days ago.

Also of note... OP stated there is no boss. He is a student. This is a student post.

 

[Martijn Roks]

Hello everybody,

The spring is undesirable component of the device, because there where problems with it in the past. Thats why they want to have a other simple component and I think the leaf spring will do the trick.
I want to apologize for my uncertainty over the project and I really appreciate the anwsers/feedback all of you are giving me.

I am going to look into all the solutions you guys gave me and make decisions based on that.

Greetings

 

[IRstuff]

The spring is undesirable component of the device, because there where problems with it in the past. Thats why they want to have a other simple component and I think the leaf spring will do the trick.

Springs WORK.IN.ALL.SORTS.OF.CHEAP.STUFF. To throw our springs because of "problems" is just plain bad engineering, unless it can be proven that springs couldn't do the job in the first place. Your school/class is doing you a great disservice here. Learning from mistakes is way more important than moving on and making different mistakes on something else.

Many of life's failures are people who did not realize how close they were to success when they gave up.

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[dgallup]

I agree, I've seen designs with relatively small, solvable problems thrown out in favor of new clean sheet designs that introduced huge new problems and in the end complete project failure.

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The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

 

[MintJulep]

The spring is undesirable component of the device, because there where problems with it in the past

A really important part of engineering is asking good questions.

WHY is the spring undesirable?

WHAT were the problems with it?

WHEN did the problems occur? In the PAST. Are the problems no longer occurring in the PRESENT? What changed.

It is critical to understand the problem before attempting to solve the problem.

You don't appear to be there yet.

 

[BUGGAR]

Five tiny air bags and a hat pin.