• Welcome to engineeringclicks.com
  • Help figuring out small mechanism to open and close hinge

    Discussion in 'The main mechanical design forum' started by davidcondrey, Aug 21, 2014.

    1. davidcondrey

      davidcondrey New Member

      Joined:
      Aug 2014
      Posts:
      2
      Likes Received:
      0
      I'm working on a pretty small part consisting of an upper and lower section connected with a hinge so that the can pivot 90 degrees. The part needs to be controlled by an internal mechanism though. Originally I thought to use an actuator but the smallest I could find were from Firgelli and they are still too large. Can anyone offer a suggestion as to what I should look into? I am not a mechanical engineer, just learning as I go..

      I've got a CAD design done here. And a rough sketch below:


      [​IMG]
       
    2.  
    3. Lochnagar

      Lochnagar Well-Known Member

      Joined:
      Feb 2011
      Posts:
      157
      Likes Received:
      0
      There are many ways to do this - but the obvious one is to just add an extension onto the lid - see pictures below.

      Hope this helps.

      [​IMG]
      [​IMG]
       
    4. Erich

      Erich Well-Known Member

      Joined:
      Feb 2012
      Posts:
      222
      Likes Received:
      2
      How big is it?
      What are the forces it has to exert?
      What initiates the motion?
      Does it have to open and close?

      A more completely defined problem will yield more useful answers and ideas.
       
    5. davidcondrey

      davidcondrey New Member

      Joined:
      Aug 2014
      Posts:
      2
      Likes Received:
      0
      ---

      Sorry for the late reply.. I didn't have much info until just today I got some more specifics..

      The size of the part is exactly why this is becoming such a complex endeavor. The part is only about 2 3/4 inch x 1" by 1". If necessary the housing can be increased on the Y axis but the length (X) and width (Z) can not get any larger. The part itself could even be designed differently as long as it remains within those spacial restrictions and has a flat surface top and bottom like this box does.

      The top of the part will have another item attached to it with two small bolts (this is the reason it needs to be flat on either side), this item will stick straight out around 8 - 12 inches and weight <= 3 lbs and have approx <=5nm of wind resistance pushing against it when opening.

      It needs to hold in both positions and when operating, needs to complete the movement within <= 15 seconds, preferably closer to 5 - 10 sec.

      The best actuator I was able to find was the Firgelli PQ12 which would have worked if only it were a little bit smaller but the way it is, it's too large. None of the other smaller actuators I've been able to find, come anywhere near having the strength I need, creating the torque has been an obstacle.

      This is really about all the detail I have at the moment. Thank you!
       
    6. Lochnagar

      Lochnagar Well-Known Member

      Joined:
      Feb 2011
      Posts:
      157
      Likes Received:
      0
      If you take your actuator Firgelli PQ12 and add a "trunion" to it (near where the 3mm half hole is located). You will probably need to clamp the trunion on to this actuator. See picture below of what a trunion mounted cylinder looks like if you are not aware of what a front mounted trunion on an actuator looks like. By adding a trunion - you will find the operating geometry is significantly improved- and it is a fairly standard technique when the space available is limited. However, you will need to make use of - what you say is possible "If necessary the housing can be increased on the Y axis".

      http://www.aphusa.com/index.php/portfolio-view/c10_industrial_hydraulic_cylinders/

      Hope this helps.
       
      Last edited: Aug 28, 2014

    Share This Page