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SVNsvn
Guest
Hello. Anyone have any information (or model better
)on the design of a living butterfly hinge such that is used on a flip top closure for toothpaste? Thanks. Designer from Belarus SVN .
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SVNsvn
Guest
This is my model for molding
, but i am not sure that is right way in dimensions of sections of living hinge .View attachment 4695
Edited by: SVNsvn
Edited by: SVNsvn
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mcgowanp
Guest
Information like this generally isnt shared around in my experience, I normally end up prototyping or rapid tooling tooling to refine the design. I dont have any experience in this type of hinge, but PM me and i will send you on a scan that I have taken of an hinge like this, might be some extra info for you.
Paddy
Paddy
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michaelpaul
Guest
did you try "The Google"?
http://engr.bd.psu.edu/pkoch/plasticdesign/living_hinge.htm
http://www.efunda.com/designstandards/plastic_design/hinge.c fm
http://injectionmolding.blog.quickparts.com/2009/08/20/desig n-for-a-living-hinge-for-injection-molding/
and those were just the top three search result returns...........only 421,000 to go
http://engr.bd.psu.edu/pkoch/plasticdesign/living_hinge.htm
http://www.efunda.com/designstandards/plastic_design/hinge.c fm
http://injectionmolding.blog.quickparts.com/2009/08/20/desig n-for-a-living-hinge-for-injection-molding/
and those were just the top three search result returns...........only 421,000 to go
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design-engine
Guest
In my plastics part design class we cover these types of hinges (tangible caps) and offer several modeling strategies. We also share a box of live hinges with the group. The idea is to give as much experience all in the time allotted. In that type of hing note that the cap flips up once it reaches past a specific angle.The opening of the cap acts like a cam and speeds up to flip open. Common technique is to mold the cap in an open position offering tension for the cam action. (so to speak)
The idea is to try to keep the mold what we call 'steel safe' as you can always go back to cut more off the steel to make the plastic thicker in some areas. We do this so we can go back to change the strength or speed of the lid that cams open.
[url]http://proetools.com/category/courses/part-design-and-manufa cturing[/url] < plastic part design at the bottom
Edited by: design-engine
The idea is to try to keep the mold what we call 'steel safe' as you can always go back to cut more off the steel to make the plastic thicker in some areas. We do this so we can go back to change the strength or speed of the lid that cams open.
[url]http://proetools.com/category/courses/part-design-and-manufa cturing[/url] < plastic part design at the bottom
Edited by: design-engine
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mcgowanp
Guest
Not the same Hinge Bart as what SVN is looking for.
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SVNsvn
Guest
I find a lot of EC and US patents of "butterfly" hinge.
Dig up all "The Google". The prototyping model is thoroughly measured where i was able to do it(living hinge has a rumpled surface). I have constructed more than one model (several living hinges), latest and better one see above. But i doubt about living hinge, it must be elastic and springy. Nevertheless the technical documentation for the mould is ready. It is very interesting assignment. Not so difficult for ProE...
I'd like that anybody with some experien
Dig up all "The Google". The prototyping model is thoroughly measured where i was able to do it(living hinge has a rumpled surface). I have constructed more than one model (several living hinges), latest and better one see above. But i doubt about living hinge, it must be elastic and springy. Nevertheless the technical documentation for the mould is ready. It is very interesting assignment. Not so difficult for ProE...
I'd like that anybody with some experien
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muadib3d
Guest
well this link below seems to be worth to consider
http://engr.bd.psu.edu/pkoch/plasticdesign/living_hinge.htm
http://engr.bd.psu.edu/pkoch/plasticdesign/living_hinge.htm
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78finn
Guest
mcgowanp is quite right...this sort of information is generally not easy to get hold of...mainly for the reason that every hinge detail will be slightly different (swing arcs, clip detail, materials etc). Having said that the wall sections for such hinges are generally around 0.2 - 0.3 for the hinge itself, with a thicker outside wall to prevent tearing across the hinge, which I see you have included.
I have just finished a very similar hinge for a cap I have been working on. I ended up working very closely with the tool maker/moulder to get the hinge as I would like it - one round of tool mods required. In the end, no CAD was drawn up - the tooling company advised/created the feature. This sounds like lazy design...but this is very common. Do you know who the tool maker/moulder will be? My advice would be to finalize everything else, leave the hinge out and speak to them directly about the hinge detail first - before doing the CAD yourself.
Also...one very important aspect of butterfly hinge design is the gate location. You will want the material flow to be running over the hinge and not along the hinge...this will help keep the hinge very strong and decrease the likelihood of it tearing. Mould flow analysis is there for critical to insure the flow of material is working for you.
But really, don't waste your money on a course and speak directly to the moulder and there engineers - far more time/cost affective.
Edited by: 78finn
I have just finished a very similar hinge for a cap I have been working on. I ended up working very closely with the tool maker/moulder to get the hinge as I would like it - one round of tool mods required. In the end, no CAD was drawn up - the tooling company advised/created the feature. This sounds like lazy design...but this is very common. Do you know who the tool maker/moulder will be? My advice would be to finalize everything else, leave the hinge out and speak to them directly about the hinge detail first - before doing the CAD yourself.
Also...one very important aspect of butterfly hinge design is the gate location. You will want the material flow to be running over the hinge and not along the hinge...this will help keep the hinge very strong and decrease the likelihood of it tearing. Mould flow analysis is there for critical to insure the flow of material is working for you.
But really, don't waste your money on a course and speak directly to the moulder and there engineers - far more time/cost affective.
Edited by: 78finn