Mayday! Mayday!!!

[raj]

It looks like 'gearing' can be done at more than one place in this new speed doubler design.

see drawing below.

Raj

[raj]

Here I go again, folks!

I just got an idea of a new speed doubler design.
Drawing below is self-explanatory.

What you make of this one?

Raj

[raj]

This is what I posted way back on 25th January last, on the very first page of this, my thread, with the drawing below.

Hi all forum members!
Please accept my seasonal greetings from the tropical Island 'Mauritius'

I am not claiming anything. I am only trying to assess with all your help whether my new concept of a gravity wheel looks plausible enough, THEORITICally, to warrant further persuance.

In order that you can follow my concept, I am putting here, below, two drawings that would show you how the two wheels are geared ( planetary gear style) so that the smaller turns in the same direction and at twice the speed of the larger wheel.
The drawings are self-explanatory.

Raj

[raj]

My drawing posted on 25 January 2012

[raj]

Raj

Firstly, IMHO, you need to ground the two smaller gears. This can be done using a large suspended weight off the axle . Affix the gears to the pendulum shaft.

Secondly, you need to configure an additional drive gear which will back feed the OB torque produced by the bi-rodded weights into the outer or inner rod attachment wheels.

I, personally, have always favoured cogs within a PM design as it ensures synchronisation of all systems during rotation.

A big, simple 10th watch if you will !!!

Chris

Hello Chris!

The smaller gears are now grounded.

Raj

[path_finder]

Dear raj,
As you know, each elbow of your design follows the path of a 'cardioid' (the reference is here: http://en.wikipedia.org/wiki/Cardioid)
As you know also, any curve obtained by the rotation of some circles, can be obtained by the combination of some rods/elbows (theorem named 'of the double generation').
In a practical way if you do NOT want to use some cogs/gears, here is an alternative:
http://www.cabri.net/cabrijava/linkage-cardioid.html
Is there any connection with the MT138 'Toys' parallelogram?
This frame assembly of rods can replace any previous set of cogs/gears.

[raj]

Dear Path_Finder,

I just spent a few hours re-checking the workings of my original gravity wheel design, the one, of which, you have so kindly done an animation here, below.

I have come to a conclusion that your animation of my original gravity wheel design WILL WORK just as well WITHOUT any gearing of the two wheels required. I believe the weights themselves will make the smaller wheel turn at twice the speed of the larger wheel.

Could you again, kindly do another animation of the original gravity wheel. This time without any gearing requirement in the design.

It may well end in complete mess of the design.

Raj

[raj]

This is why I think the proposed new animation will work just as well as the one above.

The drawing below shows the eight weights in my original gravity wheel design at a start position.
You will appreciated that five of the eight weights are in locked/elbow positions at the centre of the wheel and as such they are not acting on the wheels' motion.

The remaining three weights are acting on the wheels. Two are providing clockwise torque and one counterclockwise torque. We have a net positive clockwise torque, which will, for a 45 degrees rotation of the large wheel, will pull and rotate the smaller wheel 90 degrees.

Path_Finder's new animation will, no doubt,disprove my conclusion.

Raj

[path_finder]

Dear raj,
I don't understand your request.
All details of the successive positions have been published here:http://www.besslerwheel.com/forum/viewt ... 8378#98378.
Why your latest drawing above?

[raj]

Dear Path_Finder,

Please kindly re-run the animation without any 'speed doubler' or 'gearing' instructions, allowing the large wheel and the small wheel to rotate independently, constrained only by the the swinging weights.

Raj

[raj]

Path_Finder,

I should have asked you this first:

How and why is the smaller wheel rotating at twice the speed of the larger wheel in your animation of my gravity wheel design above?

Raj

[path_finder]

Dear raj,
First, an answer to your question:
If the elbows are fixed on the rim of a roller, rotating (with contact) around the central roller, each roller rotates TWO TURNS on itself during one turn around the central roller.
This is the well known experiment of the two coins (you can verify yourself).
The double rotational speed is needed for a correct reset of the elbow positions.

You will appreciated that five of the eight weights are in locked/elbow positions at the centre of the wheel

I guess you are wrong: there are only FOUR weight located permanently at the center.
But anyway this don't change the summary of the torque, positive in any case.

I have come to a conclusion that your animation of my original gravity wheel design WILL WORK just as well WITHOUT any gearing of the two wheels required. I believe the weights themselves will make the smaller wheel turn at twice the speed of the larger wheel.

You could be right! my latest wheel (see the two shots below) has the same tendency.
This model does NOT work, the reason is simple: I made a mistake in the dephasing (a value of 90 grades is stupid, this specific design being replicated every half of turn), which must be of 45 grades for FOUR weights and 22,5 grades for EIGHT weights in view to benefit of a maximum of overlapping. So far I have to modify it again.

As you can see at the top of the second shot, I kept only four of the 16 original marbles, in view to reduce the friction at the minimum.

[path_finder]

Dear raj,
When applied to eight weights your design is not far from this previous one (remember here http://www.besslerwheel.com/forum/viewt ... 9888#89888) and it is not a surprise to be fronted to the same difficulties, in particular how to implement the vilbrequin.
The need for each set of pendula to be linked at a pin rotating with a double speed, is difficult to assume on a mechanical point of view, because no shaft can pass-through the central area due to the swing of the pendula.
So far how to build this mechanism?

I ever though Bessler did NOT used any cog/gear, but almost a kind of imbricated polygons, much more easy to implement within a technology essentially based on the wood. Remembering some old attempts I think there is a way to build four independent speed doublers, using this technology: I will publish soon the corresponding animation.

For the moment, and in the same subject, I made some investigations about your second design (this one with a small drum rolling INSIDE another big drum), and I arrived at the conclusion the best way could be to invert the positions (to suspend the big drum on the small one), which seems to be much more stable and efficient (no slippery). The way to do that job is shown in the next animation.
Just for feed the idea.

[path_finder]

Dear raj,
As shown in the drawing below a very simple speed doubler can be made using some polygons, with the correct reduction ratios.
Built with some thin wood parts, this kind of reductor is independent and can be replicated any times as required, in particular for each set of pendula.
The timing is stable, therefore the synchronization of the multiple sets of pendula. A demonstrator will confirm this idea.


edited:
This assembly can be linked to the Apologia drawing, like previously explained here: http://www.besslerwheel.com/forum/viewt ... 3502#53502

[raj]

Dear Path_Finder,

You said :
' The need for each set of pendula to be linked at a pin rotating with a double speed, is difficult to assume on a mechanical point of view,BECAUSE no shaft can pass through the central area due to the swing of the pendula. So far how to build this mechanism?'

Maybe you did not pay attention to this drawing of the inner wheel, I posted some time back.

It works on the same principle as in this car engine-pistons animation below.

Raj