Flip top cap closing automatically in mould?! 3

[blekiwajt]

Cheers all good people,

I was in a technical meeting and one of mould engineers said that he designed flip top cap mould that when cycle is finished automatically closes the cap so it can cool down closed?!

Is that possible anyway...

Thanks for clarifying,

Mile

 

[blekiwajt]

i saw some moulds with rolling bars that flip the cap but how functional is it?

 

[patprimmer]

It is not only possible, it is essential for the PP live hinge is to survive more than a few cycles. By working the hinge through its full range or more as it cools, the molecules across the thin part of the hinge are drawn parallel, just like the stretching process in fibre manufacture. This close packed very parallel molecular orientation greatly increases the strength along the axis of molecular orientation.

Regards
Pat
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[cpretty]

Capitol vial have some details here.

http://www.capitolvial.com/tech/overview.aspx

Craig Pretty

 

[blekiwajt]

Thanks all for replies!

Cheers!

 

[Paulkuklych]

It is easy to do if it is part of the injection mold design. All it requires is a support bracket (which you can custom make to suit size of mold) on each side of the mold which holds a pneumatic cylinder bolted to the appropriate number of rods which move forward as soon as the mold opens which closes the lid. If a 16 cavity mold configuration is 2X8 then 8 rods per side are needed.

Note: an ejector pin must first push the lid forward off the molding so that the rods will contact the lid in the right position.

Paul.