William F. Skinner - 1939 Gravity Power

[k4zep]

If possible, please send it to pontozero36 at Google MAIL dot com

I would also like a copy of the video/sketches sent to

k4zep @ Yahoo dot com

Thanks
Ben

[velacreations]

has anyone been able to test power output with their replication?

[purelyprimitives]

Hi,

I was interested to see the 1939 Pathe movie clip of William Skinner's "Gravity Power" machine.
Watching the clip, I could see the operating principles clearly so made the attached drawing. I then built two Meccano models to test the drive principles employed in this device.
The leverage assisted, reciprocating drive rotates the upper mass through the gravitational torque produced each time the mass is lifted on its tilted axis. i.e. every 180 deg. of rotation. (The upper mass has to be swung by hand to start this cycle).
The rotating upper mass, again with the assistance of leverage, tilts the shaft
supporting the lower mass, again invoking the power of gravity and rotates
the lower mass with its output drive.
I made videos of the separate and combined stages operating.
My two stage model represents one quarter of Mr Skinner's machine, and operates very smoothly.
Ideally, there should be a mirrored mechanism, which would enable the
reciprocating input moments to balance perfectly and cancel each other out.
As it is, my model is driven by a small 24v D.C. motor running on barely 2v @0.25a.
I hope that this contributes useful information to those interested.
(Sorry, I've found there is no provision to upload video on this
site. I'll be happy to send videos directly to an email address.)

Regards,
Dave Q.

Hi Dave,

Small correction on your diagram. The output is 1.5 HP not 150 HP. The claim is that it develops 1200% increase which is 12 times the input. 12 times 1/8 is 1.5 HP.

This is one of the things that doesn't make sense because you couldn't really drive all of that equipment with 1.5 HP.

[goldpro]

Hi,

I was interested to see the 1939 Pathe movie clip of William Skinner's "Gravity Power" machine.
Watching the clip, I could see the operating principles clearly so made the attached drawing. I then built two Meccano models to test the drive principles employed in this device.
The leverage assisted, reciprocating drive rotates the upper mass through the gravitational torque produced each time the mass is lifted on its tilted axis. i.e. every 180 deg. of rotation. (The upper mass has to be swung by hand to start this cycle).
The rotating upper mass, again with the assistance of leverage, tilts the shaft
supporting the lower mass, again invoking the power of gravity and rotates
the lower mass with its output drive.
I made videos of the separate and combined stages operating.
My two stage model represents one quarter of Mr Skinner's machine, and operates very smoothly.
Ideally, there should be a mirrored mechanism, which would enable the
reciprocating input moments to balance perfectly and cancel each other out.
As it is, my model is driven by a small 24v D.C. motor running on barely 2v @0.25a.
I hope that this contributes useful information to those interested.
(Sorry, I've found there is no provision to upload video on this
site. I'll be happy to send videos directly to an email address.)

Regards,
Dave Q.

Hey, another meccano builder- great! Yes please, sure would like to see the video. If you can't post on utube my email is goldpro at Hotmail dot com.
On the diagram what do you mean by "90* angle between A and D" ?

thanks for your efforts.
Tom

[Michael John Nunnerley]

Hi all

What I am going to do is document how I see it from the top down of the device, if anyone finds that I have not seen something then please tell me, but I have been going over and over the videos and looking at possibilities of how a part works in each area of the machine.

I agree with Aaron that there are for sure other ways of doing things with the advanced engineering we now have, but first I think we need to understand how he did it 1939 with what was available or he could make.

I am going to reference various videos that have been looped and also the original full video. At each section, there are three, I will try to explain what it is doing and it's effect. Each of the three sections are totally independant apart from a brushing by friction, normal when each section is indirectly coupled.

What I have said before about the maximum speed, I will stand by, that is not to say it can't go slower, it does under load and at the same time increases torque automaticly. The faster the levers move at the top of the machine, will not make any difference once it is at it's idle speed, the idle speed is determined by the amount of weight at the bottom. It is all to do with centrifugal and centripetal force in relation to a mass but with an extention to a moving center of gravity (that last part is what you will not find in a book).

Please read and study this:-

http://physics.nyu.edu/~physlab/GenPhysI_PhysII/Centripetal-Force-11-07-2012.pdf

More to come, but in a pdf format when finished

regards

Mike

[Aaron]

output of Skinner machine

Hi Dave,

Small correction on your diagram. The output is 1.5 HP not 150 HP. The claim is that it develops 1200% increase which is 12 times the input. 12 times 1/8 is 1.5 HP.

This is one of the things that doesn't make sense because you couldn't really drive all of that equipment with 1.5 HP.

That never made any sense to me. 1.5 HP is about 1200-1300 watts and I need that just to max out my one single small 8x20" lathe.

It is possible he intentionally downplayed it so it didn't seem any more crazy than it already is or maybe it was 12000% for 15HP worth of work.

[Aaron]

Right Angle

On the diagram what do you mean by "90* angle between A and D" ?

The whole Skinner mechanism is like the Sun, Earth and Moon where it takes one day for the Earth to revolve around the Sun and the Moon always stays in the same position relative to the Earth and Sun like the 3 points of a right angle triangle and the hypotenuse is from the Sun to Moon and the right angle is at the Earth..

David Q is right - he's the only other one to spell it out, but it is on the drawings by both Arto and I.

A
|
|
|
|_________
B............. C

A is the top of the lower shaft.
B is the input lever rod.
C is the upper weight.

That is a top view of the Translation coupler.

Some drawings I've seen have it wrong.

Luc, your build is not geometrically correct - it's more like an equilateral triangle. It needs to be corrected as shown.

Go back to my video where I do the paper example of the translation coupler and you see the importance of having these relationships correct... like in the above diagram I'm showing, if you kick B towards the A direction while the coupler is spinning clockwise, C will have the best reaction in the same clockwise direction. There is no equal or opposite reaction here, the reaction is directly converted into forward motion. (reactive power is converted to forward work.

If C is up towards the right of A for example and you kick B towards A, then you're going to divert much of the reaction out towards the 2-3-4 o'clock position, when you really want the weight to be where it is shown so that when B is kicked towards A, the full reaction of C is in the same direction it is already traveling towards 7 clock or so, which means you have put the reactive power element in phase with where the real power already is.

This is yet another principle of getting mechanical reactive power to actually do work in the forward direction.

If you really contemplate the above, it can be applied to an infinite number of mechanical machine possibilities.

Just create mechanisms where the mechanical reaction elsewhere is in phase with the forward work and you have just thrown the 3rd Law of Motion out the window.

There is no such thing as "for every action, there is an equal and opposite reaction". That interprtation of Newton's 3rd law is all brainwashing.

The truth is that all the total forces are divided between two frames of reference. One is usually the forward intended one and the other is usually a reaction, but that doesn't mean anything. You can simply cause the reaction to not be opposite at all but additive to the initial forward power. Therefore, you do not wind up with an equal and opposite reaction, you wind up with a minimum of double minus losses. That is just one of many gain mechanisms in the Skinner machine.

This machine does that, Veljko's does it, Ramos' does that, etc... You could spend 10 lifetimes applying this principle in mechanical devices and you'll never run out of applications.

Plus in the Skinner machine, that reaction going forward happens right at the peak of the narrow end of the Ellipse - yet another gain mechanism.

I hope that helps.

[goldpro]

Here is the latest design form, the rest is just details and small adjustments, the top wobble design is sound and reliable, these are the sort of designs that a factory production machine designer like Skinner would have done. I have supplied parts to hundreds of old machines over the years many customers that used these types of set ups for bottling and such, by adapting old 1930's, 40's etc equipment they saved money. So if someone wants a accurate replication, these outlines should help. More pages for all the top, bottom and middle wobbler are in the works, looks like about 40 pages of details and engineering to finish. Regards Arto.

Artoj,

I'm surprised to see in your diagram that your pulley ratios seem to be pretty much exactly the same as those shown in the ebay picture.
How did you figure that out??? Amazing!

I see you have a 6" pulley on the motor, then a 10" pulley on the one driven with the cotton thread and a 3&1/2" flat belt pulley on the same shaft. Have I got the correct? Looks like another 3&1/2" flat belt up top on the fast and loose mechanism.

Just wondering if you have values for the diameter of the large 5 spoke pulley up top and for the speed of that pulley?

Looks like the drivetrain then goes horizontally to a miter gear which probably meshes with another miter and then out horizontally through several pinions and finally to the devise driving the input lever rod.

You spec an 1150RPM motor. I think that would be a 6 pole. I wonder if
such motors were very plentiful in 1939? A 4 pole 1725RPM might have been easier to obtain. In either case, I'm thinking the transmission of speed would be reduced, which would increase the torque to a very high amount.

Any guesses what the torque would be on the lever rod driver?

thank you for your efforts thus far.

Tom

[goldpro]

Go back to my video where I do the paper example of the translation coupler and you see the importance of having these relationships correct... like in the above diagram I'm showing, if you kick B towards the A direction while the coupler is spinning clockwise, C will have the best reaction in the same counter clockwise direction.

Aaron,

Thanks for the 90* explanation, that makes sense now.

In the above paragraph you mention first clockwise then you say in the same counter clockwise direction. ? as usual I'm confused ?

How about an explanation for this one:
In the diagram from Dave he has this listed as his 2nd point:
"As mass A is raised, then falls again by gravitational force every 180* of rotation"
Does he means the weight actually raises when viewed from the side?

thank you
Tom

[gotoluc]

Update,

Elliptical mechanism in operation without lever connected: https://www.youtube.com/watch?v=Kn_gI1Ae6d8

Elliptical mechanism failed to operate correctly with lever connected: https://www.youtube.com/watch?v=T4wvNRO4_MU

This mechanism needs too much precision for experiments.

I'm also starting to think 2 gravity units 180 degrees out of phase may be required to balance out the motor (prime mover) input.
Also we don't understand how the primary input mechanism is made, so we're working in the dark.
I'm now starting to think the input mechanism is connected to the lever shaft rotation. You can see when Mr. Skinner turns the lever by hand and the input pulley turns. I've noticed this for a while but it didn't connect till now.

Luc

[purelyprimitives]

That never made any sense to me. 1.5 HP is about 1200-1300 watts and I need that just to max out my one single small 8x20" lathe.

In the newspaper article he does say that his lathe would normally require 2 HP.

It is possible he intentionally downplayed it so it didn't seem any more crazy than it already is or maybe it was 12000% for 15HP worth of work.

Its possible he was downplaying the number. However, the article does state that he 'estimates' the multiplication factor at 1200%. Someone who is able to conceive and execute a device of this complexity would seem to be someone who could 'estimate' something close to what it actually would be.

Too bad we'll never know why he never patented this machine.

[alfilmx]

I hope that this contributes useful information to those interested.
(Sorry, I've found there is no provision to upload video on this
site. I'll be happy to send videos directly to an email address.)

Regards,
Dave Q.



If possible, please send it to [email protected]

thanks in advance Dave Q.

[purelyprimitives]

I hope that this contributes useful information to those interested.
(Sorry, I've found there is no provision to upload video on this
site. I'll be happy to send videos directly to an email address.)

Regards,
Dave Q.

Dave,

If you can send the video file to [email protected], I'd be happy to upload it to YouTube for you and provide a link here if that would help.

Regards,
Charlie

[gotoluc]

A
|
|
|
|_________
B............. C

A is the top of the lower shaft.
B is the input lever rod.
C is the upper weight.

Luc, your build is not geometrically correct - it's more like an equilateral triangle. It needs to be corrected as shown.

Go back to my video where I do the paper example of the translation coupler and you see the importance of having these relationships correct... like in the above diagram I'm showing, if you kick B towards the A direction while the coupler is spinning clockwise, C will have the best reaction in the same counter clockwise direction. There is no equal or opposite reaction here, the reaction is directly converted into forward motion. (reactive power is converted to forward work.

I hope that helps.

Hi Aaron,

when the topics first started I did my own investigation and wanted to do experiments based on what I was observing before going along with what was first shared.

I posted the picture below at the OU topic on June 14th (some weeks after I had noticed this) if you look closely the upper levers position in the translation plate is not in line with the lower shaft.
Noticing this I decided to offset mine as well. However, since I used a self alining pillow block as bearing on the translation plate for the lower shaft, I can adjust the lower shaft to infinite positions.

Hope this clears your concern?
Revisions may be needed?

Luc

[sterlingda]

Feature page posted

I've posted a feature page about this at Directory:William F. Skinner's 1939 Gravity Motor - PESWiki

You guys are doing a great job at trying to replicate this.