Discover the Top Types of Counterweights for Efficient Physical Work

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Discussion Overview

The discussion centers around various types of counterweight devices and their applications in performing physical work. Participants explore different mechanical systems, including pulleys, levers, and hydraulic cylinders, while also considering unconventional examples like Ferris wheels and funicular railways.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant lists several counterweight devices, including pulleys, levers, hydraulic cylinders, and a weighted wheel, and questions the classification of a Ferris wheel with distributed weights as a counterweight.
  • Another participant asks for clarification on what constitutes a "counterweight device" and suggests that a flywheel and crankshaft counterweights could fit this definition.
  • There is a discussion about the mechanics of counterweights, with one participant noting that moving a weight up against gravity can be balanced by another weight being pulled down, requiring minimal external force to overcome friction.
  • Concerns are raised about the energy required to accelerate a Ferris wheel with counterweights, indicating that more energy would be needed compared to a non-counterweighted system.
  • Participants mention examples like garage door springs and water balance funicular railways as practical applications of counterweight systems.
  • There is a comparison between different mechanical systems, such as the Falkirk Wheel and the Foxton Locks Inclined Plane, highlighting their efficiency in solving similar problems through different methods.
  • Discussion includes the classification of devices like sash windows and their relation to pulley systems.

Areas of Agreement / Disagreement

Participants express differing views on the classification and functionality of various counterweight devices. There is no consensus on the definitions or the implications of using counterweights in systems like Ferris wheels, and the discussion remains unresolved regarding the energy dynamics involved.

Contextual Notes

Some participants express uncertainty about the definitions of counterweight devices and the assumptions underlying their classifications. There are also unresolved questions about the energy requirements for different systems and the mechanics of acceleration and friction in counterweighted devices.

gloo
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I have been trying to gather a list of counterweight devices that are designed to do some kind of physical work. I was wondering if anybody could clarify or add to my list?

List:

1. pulley ( simple or compound)
2. lever
3. hydraulic cylinder (with equal dimension cylinder and equal mass on each side
4. Weighted wheel?

I was wondering if something like a large Ferris wheel with an equal distribution of large weights (say 1 ton) were installed all around -- is this a counterweight of a sort? The only power needed to turn the wheel is the power needed to overcome the friction? I don't know what kind of work this wheel could do but my query is how hard it would be to turn even though there are heavy weights distributed evenly.
 
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Baluncore said:
I think you need to be more specific as to what you mean by “counterweight devices”.
Is a flywheel a counterweight device ?

The crankshaft in a fast IC piston motor has counterweights to balance each piston.
https://en.wikipedia.org/wiki/Crankshaft#Internal_combustion_engines
https://en.wikipedia.org/wiki/Crankshaft#Engine_balance

https://en.wikipedia.org/wiki/Counterweight
Google 'counterweight devices'
Hmmm..I guess you are right -- I am not thinking of a mechanical advantage (less force more distance) as much as devices that uses a counterweight where when one weight is moved up against gravity, it has the other one or more weight being pulled down with the assist of gravity to totally balance that. The result would be only small amount of external force being applied to overcome any friction in the movement.

I know how the top 3 works. But the weighted wheel can have 2 or more weights in the balance placed at the other side of the diameter of the wheel. This balance would allow the wheel to be moved without any more force other than that required to overcome any friction at the center axial correct?

So isn't the crankshaft with counterweight considered as a lever type classification? Is there any other device or method... especially in the classical machine category?
 
 
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Nidum said:

Thanks..I have seen this before -- this would fall under the weighted wheel category? I guess if it could only go up and then down but not all the way around it could be a lever huh?
 
gloo said:
I am not thinking of a mechanical advantage (less force more distance) as much as devices that uses a counterweight where when one weight is moved up against gravity,
Garage door springs serve the same function, but without the need for all the weight (and are more compact)... :smile:
 
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gloo said:
I have been trying to gather a list of counterweight devices that are designed to do some kind of physical work.
snip
I was wondering if something like a large Ferris wheel with an equal distribution of large weights (say 1 ton) were installed all around -- is this a counterweight of a sort? The only power needed to turn the wheel is the power needed to overcome the friction?

That's not quite correct.

Energy is also needed accelerate the mass from stationary up to operating speed. Adding counterweights to a Ferris wheel would mean more energy is needed to accelerate the wheel. More power as well if you want it to take the same time to reach operating speed.

You might be able to recover that energy when the wheel slows down again but it depends how you slow the wheel down. If you use a friction brake then it's wasted as heat.
 
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Have a look at ' water balance funicular railways ' . Delightfully eccentric but quite practical as well .
 
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Nidum said:
Have a look at ' water balance funicular railways ' . Delightfully eccentric but quite practical as well .
Oh that's pretty cool too - Thanks! :)
 
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In a domestic setting the sash window.
 
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  • #12
Jobrag said:
In a domestic setting the sash window.
This is more like a pulley system no?
 
  • #13
gloo said:
This is more like a pulley system no?
Yes. One problem with the OP question is the archaic concept of categorising fundamental classes of machine components.

Both the Falkirk wheel and the Foxton Locks Inclined Plane solve the same problem, but in different ways and with similar efficiency. One has a balanced wheel, the other has a wedge and a pulley system. The water passed in both cases is only the difference in displacement of the boats being transported, plus leakage. The system is balanced so acceleration and friction are the only cost.

gloo said:
I was wondering if something like a large Ferris wheel with an equal distribution of large weights (say 1 ton) were installed all around -- is this a counterweight of a sort? The only power needed to turn the wheel is the power needed to overcome the friction? I don't know what kind of work this wheel could do but my query is how hard it would be to turn even though there are heavy weights distributed evenly.
When a small, partly patronised, Ferris wheel is being loaded they try to balance the position of the mass of people on the wheel so as to minimise the resultant torque. The small wheel can be stopped and started. Big wheels such as the London Eye turn continuously so they do not have to accelerate and decelerate the entire 320 tonne mass of capsules, only the people who step on as a capsule passes need be accelerated.
 

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