• Welcome to engineeringclicks.com
  • Mechanism similar to retractable pen

    Discussion in 'The main mechanical design forum' started by MAJoplin, Nov 8, 2015.

    1. MAJoplin

      MAJoplin New Member

      Joined:
      Nov 2015
      Posts:
      2
      Likes Received:
      0
      Hello,

      I am working on making a custom lid for a travel mug that I have. I would like to have a push button that will open and close a seal on the drink spout. The concept currently in my mind would be to use a mechanism similar to a retractable pen where when I push the button the container will be open and stay open. A second push will then close the container.

      I did some searching on the web and on this forum and this is the best idea I have so far.

      If anyone has any other suggestions I would greatly appreciate your guidance.

      Sincerely,

      Matthew
       
    2.  
    3. Dana

      Dana Well-Known Member

      Joined:
      Sep 2010
      Posts:
      342
      Likes Received:
      3
      I have a coffee pot made by Black & Decker that has a lid that does just that. I've never attempted to disassemble it to see what's inside the mechanism, though.
       
    4. K.I.S.S.

      K.I.S.S. Well-Known Member

      Joined:
      May 2014
      Posts:
      172
      Likes Received:
      0
      I also have (had) a flask that performs the same function - depress the central button, it clicks into it's downward home position and then when tilted, the fluid is dispensed via a inverted well around the rim. Click the central button again and it reverts to it's previous state. It started to leak, and as it was quite an expensive stainless steel flask, I took it apart to replace the seal. The seal turned out to be OK, but the plastic detent mechanism was worn beyond economically possible repair. The function and mechanism was identical to a retractable pen, with angled radial indentations. Sorry, but it's certainly been done before, as Dana indicated.
       
    5. MAJoplin

      MAJoplin New Member

      Joined:
      Nov 2015
      Posts:
      2
      Likes Received:
      0
      Dana and K.I.S.S.,
      Thank you for your replies. I also had a thermos that functioned similarly. Mine wasn't too nice and it leaked so I tossed it and got a trusty Stanley. I wished I had taken it apart before I had tossed it so I could examine the internals. Because of how the action worked I figured it was a mechanism similar to a retractable pen. Thank you K.I.S.S. for confirming this for me.

      My concept is unique in design / styling and I do recognize that the push to open / close feature I am thinking about using is not new or novel. It is designed around an accessory item for a certain enthusiast group similar to the camera lens mugs for photographers but for a different target customer.

      I have been shopping around for manufactures and found out today that low volume injection molding tooling and design is estimated to run $30,000. Definitely a lot of money for me...:(

      Thanks again for your reply!

      Matt
       
    6. K.I.S.S.

      K.I.S.S. Well-Known Member

      Joined:
      May 2014
      Posts:
      172
      Likes Received:
      0
      Matt,
      I've got a lot of experience of mold/tool design and manufacturing, and I have to say that I'm very surprised with the numbers you've been given...
      Injection moulding isn't a low volume manufacturing process, so this makes me think that someone is pulling a fast one on you. Some companies will actually retain ownership of the tooling, even though you've paid for it (read the small print and avoid them).
      So perhaps if you've indicated a relatively low volume, they thought that they'd nail you from the start.
      I can only speak very generally as I don't know your specific requirements, but as a very broad 'rule of thumb' the cost of a pressure mould will be split fairly evenly between material cost and machining cost. As plastic injection moulding generally requires less pressure than die casting, this means that the bolster size can be reduced, thus reducing the cost.
      I'd also guess that the components of your type of mechanism would lend themselves to a multi-cavity 'family' tool, thus further reducing the cost.
      I would estimate that your mould could be manufactured for approx. $5000.00 here in South Africa (the Rand is in freefall against the Dollar and the Pound...)
      This isn't a pitch for business, by the way - I'm far too busy, and I don't make tooling. But think about it, and if you're interested I can provide you with details of some businesses that I regularly deal with. You'll get a first world product out of them.
      I wish more people would consider S.A. for manufacturing, but I think a lot of people still think we have lions running around in the streets...
      The same people also forget that we performed the world's first heart transplant and independently built a nuclear power industry, pioneered petroleum extraction from coal etc...
      And English is the lingua franca, which makes technical communication much easier.
      Cheers,
      K.I.S.S.
       

    Share This Page