Who said that Bessler used some pulleys?

[path_finder]

http://www.cuerdacontinua.com/cuerdacontinua/

[Lightwave]

wow nice webpage i like the ideas there

[bluesgtr44]

Hey P.F., try this thread.....

http://www.besslerwheel.com/forum/viewt ... ht=pulleys


Steve

[path_finder]

What is the best way to lift up two weights? a single weight and two pulleys...

[greendoor]

Why is this the best way? I don't see two weights ... why not just one pulley? I also don't like the friction effect - I would rather use solid tie rods & a balancing beam instead of rope & pulleys. A pulley can also go slack, wheras a tie rod can work in both tension & compression.

[path_finder]

Two weights and two pulleys.

[greendoor]

Clearly 2W is going to raise W to the top and then jam ... what is the point?

[path_finder]

Dear greendoor,

I regret but nothing will move on the picture.
But if you add just a small weight to the alone animal at the right side of the picture, the both at the left will be lifted up. The only particular point will be that the travel of the weight on the right side will be the double than the left side one (conservation of the work). See this Wikipedia URL:
http://en.wikipedia.org/wiki/Pulley
about in the middle of the page you will find:
In diagram 2, a single movable pulley allows weight W to be lifted with only half the force needed to lift the weight without assistance

In another topic some member asked how to lift-up FOUR weights with a SINGLE one.
It's easy: use three pulleys

[jim_mich]

I regret but nothing will move on the picture.

Not so!

You have your elephants backwards. With the block and tackle type of arrangement of pulleys that you show it would only take 1/2 an elephant (maybe a cow?) to lift the single upper elephant.

Look at it this way... two ropes support the single elephant so each supports half of the elephant's weight. Then the one rope wraps around the blue pulley, which just re-directs the pull of the rope.

[erick]

Ah, but in that scenario you have to pull the rope twice as far. The more pulleys you have in a block and tackle the more rope you'll have to pull (multiply the desired length you want to move your heavy weight by the ammount of pulleys in the block).

[path_finder]

Jim_Mich is right. I apologize for the pulley exchange (I need glasses sometime too)
This drawing should be much more useful,

[ovyyus]

Who said that Bessler used some pulleys?

Wolff described the pulley assisted lift demonstration of the Merseburg wheel:

I therefore presume that there is no doubt that the wheel is moved by an internal source of power, but we cannot necessarily assume that it is perpetual. Furthermore, the machine may be of little value to the public unless it can be improved. At the moment it can lift a weight of sixty pounds, but to achieve this the pulley had to be reduced more than four times, making the lifting quite slow. The diameter of the wheel is about twelve feet, and as well, the bearing was quite thin, about one quarter of an inch and only a sixth of its length was subject to friction.' - Christian Wolff, letter to Leibniz, examination of Merseburg wheel, 19th December, 1715.

[path_finder]

Dear ovvyus,
I we are referring strictly to the text of Wolff above, nothing demonstrates the presence of any kind of pulley INSIDE the wheel. The assumption is regarding the available power at the output of the wheel (wich seems to be not strong enough) and the possibility to increase its power by a traditional block (assembly of pulleys).
It's that true?

My question was almost related with the MT137, where the use of a single cord (ring) passing through a succession of opposed pulleys can be a valuable investigation.
What your idea about?

[ovyyus]

path_finder, my response was in regard to the title of this thread. Your question was related to MT137???

No one said Bessler used pulleys in MT137.

[erick]

My view is that if pulleys were used at all (which Bessler does seem to indicate) the were used more a "timing pulleys" than anything else. This type of timing pulley/belt arrangment would help to ensure that (para-phrasing) "when there is a upward impetus on one side of the wheel there is a equal downward impetus on the other side".