Connecting rod system to synchronize 2 movements

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Hello

I'm new. So I'll quickly introduce myself (I couldn't find a Presentation section on this forum), my name is Justin. I am an engineer but in a field other than mechanics. I am starting out in CAD as an amateur.

I want to make a piece of furniture (a coffee table) with the top separated into two parts (p1 and p2). These will be mounted on hinges (which I didn't draw). Thus, it will be possible to open / close it in order to store objects. I would like to set up a mechanism using connecting rods / levers (b1 and b2) in order to synchronize the opening movement of each of the parts (i.e. to have the angles a and b equal regardless of the position of the chainrings). I am working on the realization of this mechanism. I've tried different solutions and I've always come to the same conclusion: I need to create 2 opposite linear movements (drawn in red), with a parallel axis above the crossmember T, at points a1 and a2 (I hope what I'm saying isn't too blurry). I tried with a mechanism of the cam + connecting rods type like those found in the locking system of office cabinets but it doesn't work. Other solutions are possible: inverted racks with pinion between the two, pulley system with a cable on which one of the connecting rods would be hung at the top and the other at the bottom, using a part that would allow the axes of the 2 connecting rods to be centered, etc ... However, I would like to stay on a connecting rod system for a reason of cost and simplicity of implementation. In addition, I am limited in terms of space, especially when the table is closed.

Do you have any ideas to solve my problem?

Thanks in advance

PS: I have attached 2 screenshots: one with the table open, the other with the table closed


captures_decran.zip
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Hello

 

Thank you for your presentation. There is a "Coffee with friends" group where it is possible to get to know the community.

 

For your connecting rod system, I would tend to say to go through the schematic representation tool.

 

To do this, make a new blank assembly and then start a schematic representation.

This tool allows you to simulate movements such as your hinges.

You can constrain and dimension the sketch.

Afterwards, it allows you to extrude the shapes to have a diagram of your hinge to be fleshed out.

 

A short video to explain: https://www.youtube.com/watch?v=Owgbt10Cx1g

 

Edit: Why not go through a groove that will guide your hardware with ball bearings? (I haven't studied the trick)

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And why not a mechanism with cogwheels?

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If both hinges are to open at the same time, a cable system is required.

Or a resort but more complicated to implement...

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Hello

QQC like this see constraint animation

And yes you have to leave it free on your red axes (displacement)


mvt.mp4
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@franck.ceroux

Do you have a CAD file to provide me. The mechanism you present seems to solve my problem. However, I tried to reproduce it in Solidworks but I can't get a correct kinematics.

 

@Bart

Thank you for your answer. I was already familiar with this feature and had seen this video before. Here, I preferred to post a screenshot of my assembly in order to better visualize its different components.

Thank you to the others for responding.

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Hello SW 2015 attachment.

It's just a diagram that will have to optimize the lever arms and pivot points.  


rep_shematique.sldasm