×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

L-shaped 6-bar linkage motion

L-shaped 6-bar linkage motion

L-shaped 6-bar linkage motion

(OP)
I'm trying to open an access panel, but the packaging is very tight. I need to move sideways about 2 inches, then upward about 18 inches. The initial motion has to be very horizontal so that tends to rule out 4 bar linkages like on bus luggage doors. Also, I can't go sideways more than 6 inches or I crash into something else. Last but not least, the door can't really rotate much as it travels upward because it would hit yet another obstruction.

At this point I'm likely going to use a linear bearing that pops outward, but that requires quite a bit of trickery to make sure it won't go up before it's completed the outward motion.

Has anyone seen a 6-bar linkage that would do the L-shaped motion that I described?

RE: L-shaped 6-bar linkage motion

"Has anyone seen a 6-bar linkage that would do the L-shaped motion that I described? "

No,

RE: L-shaped 6-bar linkage motion

Nothing exact. You could try to think of a possible way to modify a straight line mechanism (3-4 known to man). One is http://en.wikipedia.org/wiki/Hoekens_linkage

peace
Fe (IronX32)

RE: L-shaped 6-bar linkage motion

instead of a linkage, could you use a track to guide the movement ?

RE: L-shaped 6-bar linkage motion

I would assume you know how to design a 6-bar mechanism with a traslating link? Because there is a method to do that. You first of all need to find a 4-bar with a coupler curve - or with part of a coupler curve that delivers your horizontal followed by vertical motion - I'd look for a 4-bar with a symetric coupler curve first as they are the easiest to understand and search for. Once you have your 4-bar coupler curve, then stick on another dyad to give you a link that translates and attach your 'thing' to that. THe main issues I think is the 'aspect ratio' of your coupler curve.

RE: L-shaped 6-bar linkage motion

(OP)
FEX32, the Hoekens would be the bomb, but the links are on the wrong side of the L.

rb1957, we looked at bendy tracks from a supplier (like a garage door), but they're several hundred dollars each.

MotionGirl, I wish I understood what you're talking about because it sounds promising, but you're speaking French to me. I'm not familiar with the terminology you used.

It's crunch time and I have to make a decision, so I'm planning to use a linear bearing with a toggle mechanism. The toggle will kick out the bottom of the linear bearing rod (top one will have to be hinged), then the door will travel upwards assisted by a gas strut. The trick will be to have a catch that prevents the upward motion from beginning until the toggle is fully extended. On the way down the toggle will keep the panel from swinging inward until the linear bearing un-straightens it.

Thanks everyone for your feedback. This was my first time posting and you've been very helpful.

RE: L-shaped 6-bar linkage motion

You never mentioned if there were a reason why it couldn't detach and simply be removed?

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

RE: L-shaped 6-bar linkage motion

(OP)
It's an access panel for an agricultural unit. It needs to move to access the air cleaner. The whole panel will weigh about 50 pounds and it's big and bulky.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources