Hello
I have to free a room from its housing by a movement that is essentially vertical, then move it laterally. An elliptical motion can combine all of this. A circular motion requires too much radius.
Can you help me by pointing me to a mechanical way to do this?
Thank you.
Hello
Do you want to talk about a mechanical design method or a motion constraint method?
A mechanical design method.
Hello
To think of the simplest mechanical system to ensure this movement according to the trajectory you want, we would have to know a little more...
By that I mean that you probably have constraints imposed, such as the embellishment, the "motorization" system (cylinder, motors...?) etc.
The system depends on these constraints.
It could be for example a system of connecting rods and stops.
The system will be manual.
A priori, a crank will be 1/4 turn and the piece would therefore be 1/4 the circumference of the ellipse whose long axis is vertical.
The dimensions don't matter at the moment, it's the principle of movement that I'd like to know. I will then adapt the dimensions according to my real needs.
Why not design a system with a fixed part having an eliptical groove with a finger inside the groove that would be movable for example?
A priori for friction and wear issues, but it is a lead to remember, indeed.
A similar track is the simple slide with a vertical part, a 90° elbow and a horizontal part, but I was trying to find a simple mechanism made up of connecting rods whose movement resulting from a point on one of the connecting rods would be an ellipse.
It is indeed possible with two connecting rods with unequal wings connecting each other for example, but the guide problem of the second link remains to be defined
For friction problems we can consider replacing the finger with a pebble, right?
For the system with the two linkages, you can take inspiration from the front windscreen wiper of the first Twingo.
For a little more precision there would have to be a diagram or something after I didn't understand at the beginning you say "A circular movement requires too big a radius." and then you talk about a crank that makes a quarter turn???
Kind regards
Bastien
I made an animation of the movement that I found and that is the closest to an ellipse so that everyone understands what I was looking for.
A connecting rod is attached to its end A while the other end B describes an arc of a circle (here from 0 to 90°). The other connecting rod has its D end attached to the B end of the first one and its C end moves in a vertical slide. The midpoint of the second describes a roughly elliptical curve (I have drawn an ellipse and it is noticeable that the point does not follow it exactly). At the beginning of the movement, we see that this particular point has an essentially vertical displacement. At the end of the movement, the displacement of the point is essentially horizontal.
Then there is indeed the "problem" of C slipping, which can be done by rolling a roller in a slide.
To have the same horizontal displacement at the beginning of the movement with a circular trajectory (end B of the first connecting rod, for example) as with this elliptical trajectory, the radius of my circle would have to be much larger, which poses problems of machine space.
I thank you all for your proposals and your help.