William F. Skinner - 1939 Gravity Power

[eltimple]

Ok changed the top part, and added second weight

very interesting startup or recovery from stall...smaller weight whips the large one

Skinner Gravity Engine Part 4 - YouTube

[Aaron]

off balance and indirectly proportionate

Ok changed the top part, and added second weight

very interesting startup or recovery from stall...smaller weight whips the large one

Skinner Gravity Engine Part 4 - YouTube

Good job on the progress!

We already know the principles but it is great to see more examples of how the output is not directly proportional to the input. when you lock up the output, the input watts hardly changes. Under a normal equilibrium system, it would have slowed the input, which would have reduced the back emf and the current draw would have skyrocketed until you burned out the motor.

Same principles applies to Jim Murray's SERPS and other electrical machines where you can load up the output without the input really seeing it. They're all universal principles.

Your lower weight looks like threaded stock with some brass nuts. Maybe try moving the nuts up to the top of the threaded stock to make it more top heavy? It will just give it more of an off balanced situation, which increases the tendency to fall - the more off balance, the more gravitational potential will convert to real work.

[eltimple]

yes i am a bit short of 10 mm brass nuts, but can more them up no problem...i will add another bearing to the input and tube around the struts so that it wil be rigid..

Now i have a small homemade pancake wind generator that works well at 600 prm , Perhaps i should install that for some current power generation tests........ i would like to do a prony test on the video head ( lol) but have to wait while a sensitive electronic scale ( 5 dollars ) from ebay gets here

[Aaron]

move the nuts up

yes i am a bit short of 10 mm brass nuts, but can more them up no problem...i will add another bearing to the input and tube around the struts so that it wil be rigid..

Now i have a small homemade pancake wind generator that works well at 600 prm , Perhaps i should install that for some current power generation tests........ i would like to do a prony test on the video head ( lol) but have to wait while a sensitive electronic scale ( 5 dollars ) from ebay gets here

I'd actually not add any more of the nuts but first try to just move them all up so they come to the top of the threads and leave them missing at the bottom end of the stock. That will be more imbalanced than if you had enough to fill the whole stock.

Can you give a link to the scale you're getting? I just have the mechanical ones. The ones I have are actually borrowed from Peter.

[eltimple]

the normal hook electronic scales are not very sensitive, they are more designed to measure kilos instead of grams with steps sizes in around 100 grams, and with my models i need to measure grams of force so steps of 100 are not much use.

My idea is to modify a standard scale so that it has a hook, i have done it before. basically i clamp a magnet on to the scales and run a thread over a pulley..

the motor in use in the last video was from a tapedeck, or a cd drive not sure which but it was one of the smallest i had.

considering i was barely drawing a watt, there was considerable torque on the output..this should work well on a pp3...lol

[afterbyrner]

Lower Joint on Gravity Machine

Greetings from Ireland.

The Skinner machine looks amazing. I am a little confused about the lower joint. Are the two parts of the ball and socket joint rotating freely of each other as in the case of a rod end in a steering rack or are they actually coupled as in the case of a constant velocity joint. It would make sense if they did rotate independently and the ball had an offset from the centre line of the output shaft. Would I be correct in assuming that the shaft that the lower weight revolves around has an offset from the centre line of the output shaft or if you could imagine the output shaft as the centre of a circle, would the ball and socket joint be on the circumference or in line with the centre of the circle? The other thing I would like to know is are the centre lines of the input and output shafts the same or offset. I understand the eliptical part. your replies would be appreciated

[afterbyrner]

Lower Joint on Gravity Machine

I wish I had looked back at the threads in a bit more detail It clearly shows that the ball and socket joint is coupled . Plan to get working on one of these soon. What better way to recycle a cv joint and a driveshaft and lower suspension hub That should cope with some serious weight.

[afterbyrner]

Centre Lines of Gravity Machine

And thank you Arto for your drawings on this thread they clearly show the input and output shafts in line with each other.

[eltimple]

I am being told that the movement is less back and forth and more rotary, so made a gimbal this morning..it will have an adjustable center since off center in the gimbal should trace an ellipse.

[Aaron]

input lever motion

I am being told that the movement is less back and forth and more rotary, so made a gimbal this morning..it will have an adjustable center since off center in the gimbal should trace an ellipse.

Did you download that video in the zip I posted? It shows exactly what what the motion of the input lever is - its really not even in question. It's right in the beginning of the original movie. The top is mostly back and forth with a bit of rotation and that makes the ellipse.

[eltimple]

i did download it but as it was an apple file i could not open it. .

[shylo]

the input

Hi All, The back and forth motion is simply a result of the input which is rotational. The input does not move the levers back and forth, it rotates the translation plate via the swing arm , the offset swinging weights ( down below) cause the rotating upper arm to swing to and fro.
That very top bracket at the beginning of the video where the four swing arms are connected I think must be spring loaded somehow.
That's the last piece of the puzzle, also happens to be the one with the least amount of footage to examine.
Just what I'm seeing.
artv

[purelyprimitives]

i did download it but as it was an apple file i could not open it. .

Its actually just a zip file that once unzipped contains an MP4 video that you should be able to play on any computer.

[eltimple]

nope unzipped it and would not play...finally converted it to avi using online tool.

[velacreations]

download VLC or another all-format video player