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Need Help! Mechanical double lid lifter

  1. Sep 28, 2009 #1
    Hi All

    I'm new to the site. And please no negative comments. Its just a waste of being helped!

    What I want too construct is a Square tubular aluminum bar 18'' long 1'' square dia with a 9'' long tubular aluminum bar place on top and hinged on each side of the 18'' bar what the two smaller bars would do is lift the two lids at the same time and at any angle from O-dgrees to 100-dgs.Like Push and pull

    How can i make one of the 9'' bars lift as the other 9'' bar is being lifted by a motor. and without any pullies or cables on the oposite 9'' bar. I seen this mechanism somewhere but can't remember where.

    Dose any one know of or see a mechanism that make one bar lifts as the other bar pulls.
    This mechanism would be extrude in the square tubular bar.
  2. jcsd
  3. Sep 29, 2009 #2


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    Welcome to PF, Cybertron.
    You won't get any negative comments here, at least of a derogatory nature. I must admit, though, that your objective eludes me. More description would be helpful.
    If the bit that I can gather is accurate, then I'm thinking of having both bars brazed or bolted to a common axle.
  4. Sep 29, 2009 #3
    Danger thanks for responding

    My objective eludes me too! Thats why I'm having a problem figuring out how too construct this as simple as it sounds but its not impossible I would need some sought of push pull mechanism that I could make from common hardware materials.

    I'll try too get a simple sketch out to make it much clear what i need.
  5. Sep 29, 2009 #4


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    What about something like this? Not to scale.

    EDIT: Oops. As drawn, the doors will be locked in place when they close (due to the over-center feature of the right-hand door). Sorry.

    Attached Files:

    Last edited: Sep 29, 2009
  6. Sep 29, 2009 #5

    looks close too what i need, but not exactly. The hinges could be used for rotation and angle position.

    The rod you included will not work in that position. And the bottom part can't be used.
    But it is close.
  7. Sep 29, 2009 #6
    What about this? (credit to nvn)

    Attached Files:

  8. Sep 29, 2009 #7


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    What about something like this? Not to scale.

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  9. Sep 30, 2009 #8

    Close. Still bottom part will not work and that top piece can't be there do too the two bar must closed at 0dg.


    Much closer the bottom still wouldn't work in my application.

    I been trying too come up with a sketch I will try to post it some time today this afternoon.

    Everyones help is appreciated.
  10. Sep 30, 2009 #9
    Here's a simple drawn up sketch too explain as best as I could in what I'm trying too construct.

    The lifter will be made from aluminum or wood.

    In the image I provide is the Lifter not the two lids, This lifter will be attach too two leaf style lids.

    As you can see in the sketch two small sq tubular bars will lift the two lids from Odgs-100dgs.

    How this should work is when any side is lifted the smaller bars either the right or left bar the opposite side will lift at the same time.

    So basicly what I need is some knid of mechanism to pull and too push open two lids at the same time as seen in the sketch.
    one side will have a motor to lift one of the bars so thats the pulling, now the same mechanism needs too push up the opposite side for the other lid too open thats the pushing. I hope this makes any since on how this lifter is suppose to function.

    I hope the sketch uploaded to this thead the image might be small do to the bit size image limit.

    Attached Files:

  11. Sep 30, 2009 #10


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    What about something like this? Not to scale.

    Attached Files:

    Last edited: Oct 1, 2009
  12. Oct 1, 2009 #11

    In your reply to my previous post, you said;

    Close. Still bottom part will not work and that top piece can't be there do too the two bar must closed at 0dg."

    Is the "bottom part" the motor? the linkage? the extension of the left-hand door?

    And is the "top piece" the cam device which would be affixed to the left door and bear upon the under-side of the right door?

    In your original post you say;
    "This mechanism would be extrude in the square tubular bar."
    and, in your sketch you appear to depict a motor inside of a 1" diameter tube...

    Why? There must be a better place to locate the motor, and requiring the drive mechanism to be "inside" the tube becomes quite complex.

    In various places you refer to 90 or 100 degrees - where are you measuring this angle?

    Finally, and with full credit to nvn for his last post, I offer an alternative mechanism... see attached.

    ps; if you save your sketch as a .jpg file or .png it will be about 20 KB.

    Attached Files:

    Last edited: Oct 1, 2009
  13. Oct 1, 2009 #12

    Yes I did say your image was close. But what i should have said is the mechanism that you're inply in your image will not work in my application.
    As stated this lifter will open and closed from Odgs in the closed position and 90dgs or 100dgs in the open position.

    Also in your image that piece thats attach too the left top side of the lid bearing on the right side of the lid wouldn't work for me.

    In my original post yes I did say extrude I ment the mechanism will go through the sq tubing.I didn't dpict any motor going into the 1''tubular bar that would be impossible even for any type of motor. I stated a motor will lift the smaller tubular bar.

    I also stated I'm looking for a mechanical mechanism that could be placed in the 1'' inch long tubular bar I did not state a drive motor mechanism at all inside the tubular bar.You stated that. Even in my sketch there is no drive motor mechanism inside the tube I stated some type of mechaninal mechanism. I also stated in my sketch that a motor will be attached to the smaller tubular bar too lift it from the closed position Odgs to the open position to 90dgs or 100dgs.

    I thing you're misunderstanding what i need. Its knid of hard too explain too anyone with out explaining it in person.

    Yes i did mention in places 90 Or 100 degee angles these angles come from the smaller liftiing bar that lifts the two lids that smaller bar will be attach to the long bar that i drawn in my sketch the angle of lift, gos form 0dgs to 100dgs.

    As for the sketch it was drawn in MS PAINT can you save an image in PAINT as a .jpg file
    or a png file I throught MS PAINT stores the file only as a Bitmap.

    If you just look at my sketch as you see there is a long tubular bar and theres two smaller bars equal too the lenght of the long tubular bar,as you lift any one of the smaller tubular bars the opposite side will lift at the same time and at any angle i want up too either 90dgs or 100dgs this is how the (Mechaninal) mechanism should work.

    Any motor that I use will only assist to lift the lid that will be attach either one side of the smaller tubular bars on the lifter. In my sketch this image is the lifter, its not the lids.The lids will be attach only too the two smaller tubular bars.

    This is why I'm trying too build a mechanial mechanism so I can lift the small tubular bars.

    This mechanism is call a push and pull mechanism I seen one before but I don't remember where. what it dose is if you lift anyone of the smaller bars they pull and push at one another too lift on side as the other side is being pull on to lift the opposite side.
    and there no motor driven mechanism too in the lifting of the bars its all mechanial.
    I will include a motor that will only assist with the weight of one side of the lid.But i wouldn't need the motor just too lift the lids. The motor is there to assist with the weight of one of the lids.

    Also. I don't have or use a CAD software what program do you use for sketching.
  14. Oct 1, 2009 #13


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    I use Adobe Illustrator. Depending upon which of my computers I'm using, that ranges from version 4 to 10. I have CS as well, but my ex-wife accidentally dumped a beer into that computer so I can't use it. :grumpy:
  15. Oct 2, 2009 #14


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    In MS Paint, select File > Save As > png, not jpg; .jpg is for photographs, .png is for graphics. What about something like this? Not to scale.

    Attached Files:

    Last edited: Oct 2, 2009
  16. Oct 2, 2009 #15

    Please explain too me how this will work, what are those sq shapes in your image.

    Remember now in my sketch this is only the lifter. The mechanial lifter mechanism must work too lift (without being attach to the lid) so if I was too pull up on one of the smaller bars in my sketch the other bar on the opposite side will lift up too and at the same time. This is how the lifter must work. Pull and Push.
  17. Oct 2, 2009 #16


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    cybertron: I now added some labels to the attached file in post 14; see the revised file. The blocks at points E and F are generic supports for linkage rod BC. No specific detail or attachment method for these two supports at points E and F is implied in my diagram. (These support blocks are called "bushing or bearing" in the diagram by tyroman in post 11.) In my post 14 diagram, linkage bars AB and CD are connected to the square tubes at points A and D by inserting a horizontal pin or bolt through the square tube (not shown). You grind off the bottom face of the square tube at point D to allow the right-hand door to rotate to 100 deg. Linkage bar AB passes through slots in the left-hand tube and long tube.
  18. Oct 2, 2009 #17
    nvn ,

    What sort of linkage part are you using to attach together bar A to B AND C to D for the two rods or bars in your image too move. And will I beable to lift either side of the small bars so the opposite side lift on its own.

    I will enclose another sketch so you can see or uuderstand better about what i need.maybe that bar attachment my work in mt new image of my lifter.
  19. Oct 2, 2009 #18

    I made a new sketch in MS PAINT. But when I (save as) .file in png as you suggested some of the image is losted the the words are disstored and blury. what is happing to the image and is this normal in saving the file in .png.
  20. Oct 2, 2009 #19
    The images which have been posted by nvn (and me) can be copied from your browser (right-click>save as) to your desktop and opened from there with MSPaint. You can then edit them as needed. When done, select File>Save As , give the image a new name (leave the extension as .png) and save it to your desktop. From there, you can attach the new edited image to your post with a description of your edits.

    If, while you have one of our images open in MSPaint, you click on Image>Attributes , you will see that Resolution: is 120x120 dpi and dimensions are 5.42" Wide by 4.38" High.

    If you want to create a new image (with the same Attributes as ours), just open one of ours in MSPaint, select Edit>Select All then right-click on the image and click Clear Selection. This will give you a blank sheet with the same Attributes as ours for you to create your new image on. Remember; when done, select File>Save As , give the image a new name and save it to your desktop (or the original image will be lost).

    I have attached a generic image of your basic design, rendered in 3D... No opening mechanism is shown. It is hoped that 3D will allow greater clarity in our communication of what will (and will not) work for you. Please edit the attached as needed and use it as a basis for further definition and communication of your needs.

    Attached Files:

  21. Oct 2, 2009 #20

    Here another sketch hpoefully to make clearer what i need.

    The sketch is only the tubular square bar lifter.

    What I need is a Mechanical Mechanism too attach too the small tubular bars on the lifter So when I Pull up on either side of any of the smaller bar the opposite lifts on its own at the same time. this sketch should make it more understandable too what i need.

    Remember If I pull up on any one of the smaller Tubular Bars the opposite side MUST lift on its own.

    Attached Files:

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