Talk:Pulley
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[edit] Page vandalism
Why does it say sex in so many places, i'm quite sure that is not the correct term.````69.217.49.84 01:07, 16 January 2006 (UTC)
- Welcome to Wikipedia. What you saw is a fairly common form of vandalism - often committed by a new user who just can't believe that we "really allow anyone to edit anything". You did the right thing by reverting the vandalism. Next time, you can also navigate over to the vandal's Talk page and log the vandalism. I am fond of the escalating series of comments {{test1}}, {{test2}}, {{test3}}, {{test4}} and {{test5}} (though you have to be an admin to carry out the last step by temporarily blocking the vandal from editing for a while). Rossami (talk) 03:00, 16 January 2006 (UTC)
[edit] Vandalism question
This page seems to get an unusually high incidence of vandalism. Normally, a page has to be either a featured article or a very public and controversial topic to be vandalized this regularly. Any hypotheses about why this page is so regularly attacked? Rossami (talk) 20:21, 28 February 2006 (UTC)
[edit] Theory of operation
I added a theory of operation section, and used two of the pulley system images from the original article. I have removed the simplest compound pulley image, because its practical implementation is not different from the diagram, which is the case for the other two - they are different from the diagrams. I also removed the "historical images of pulleys" because it didn't seem to add much, without an explanation. Maybe it could go back in under a history section? PAR 04:51, 5 March 2006 (UTC)
how about the diameter of the wheel? doesn't that have something to do with the force necessary to lift an object? —Preceding unsigned comment added by 208.71.200.85 (talk • contribs)
- Nope, nothing. The forces on either side of the pulley are the same regardless of the radius of the wheel.
Okay, actually that's for a theoretical pulley. A real pulley will suffer some slight amount of friction between the fibers of the rope as it goes around the pulley. A larger diameter pulley will deform the rope less resulting in slightly less friction. But that is a miniscule effect compared to the normal forces used on the pulley. Rossami (talk) 00:24, 8 September 2007 (UTC)
[edit] Bicycle chain pulley?
Is it correct or incorrect to call the non-driven wheels in a modern bicycle rear derailleur pulleys? The chain is kept in place by its side-plates and small "near-teeth" in the pulley, rather than by fitting in a groove. This particular application also involves no mechanical advantage--just tension adjustment. Are there other applications where chains and wheels function as cables and pulleys?--SportWagon 23:28, 18 August 2006 (UTC)
- In the context of the six simple machines, yes, a derailleur would be considered a pulley - specifically a "class 1" pulley with a mechanical advantage of 1. The fact that the "groove" is on the chain rather than on the wheel is a minor variant. The definition of something as a simple machine is based on how the force is transformed as the force does work. Any situation where the force is being carried through tension and where the direction is changed would probably count as a pulley. Rossami (talk) 12:13, 19 August 2006 (UTC)
[edit] Additional Information Needed
I think information should be added to this article to recognize a "sheave" as a type of pulley. I'm probably not the right person to add this, but I do know that they are commonly used in oceanic applications suspended from an A-frame on a ship and also for oil drilling. 65.165.72.203 17:17, 18 October 2006 (UTC)Tired_Angel
[edit] Regarding Pictures
Bad picture. The pulleys shown are what are called belt pulleys. A rubberized loop of belt wraps around both pulleys. One pulley is the source of power, the other receives power through the belt. This was a common way to transfer rotational power prior to about 1940. Threshing machines received power through the belt and belt pulleys from the steam engines.
A picture of the type of pulleys described in the article is needed. Also the article should also mention belt pulleys as well. --69.5.156.155 06:22, 24 Sep 2004 (UTC)
[edit] Re:Leavenworth Arrangement
Rossami: I am not quite sure how to use this system, but the Leavenworth Arrangement has not been known since Archimedes. It took me a year to discover, and I am an intelligent fellow. You will not find this knowledge in books, because this is the first time it has been published. If you are of the opinion that knowledge is never lost and rediscovered, or that such a thing could not be discovered in this day and age, I challenge you to find fault with the math, with the arrangement, and a previously published source describing the arrangement. Besides those objections, there can be no reasonable objection to the additions.--MarkLeavenworth 03:01, 19 October 2007 (UTC)
- @Mark: wikipedia has a very strict policy about original research: it is not accepted. See this page Wikipedia:No original research. VanBurenen 07:52, 19 October 2007 (UTC)
I'm sorry you've misinterpretted the meaning of 'verifiable'. 1)The math does not warrent the necessity of citing for verification on the grounds that it is too simple. 2)The arrangement does not necessitate citing for verification on the grounds that it is too simple. 3)Only you can dispute my right to name the arrangement, if you can provide enough verifiable citations in the public domain to dispute my claim that I have rediscovered this technology. —Preceding unsigned comment added by 66.81.190.202 (talk) 15:32, 19 October 2007 (UTC)
- You have been asked several times now to go read the Wikipedia policy against original research. It does not matter how obvious or self-evident you think this is. Encyclopedias are, by definition, tertiary sources. We synopsize the writings of others. Until it is verifiably published in a reliable source, it has no place in the encyclopedia. Either cite your sources or stop adding this content. Rossami (talk) 21:47, 19 October 2007 (UTC)
"The threshold for inclusion in Wikipedia is verifiability, not truth." OH, I see this is not an encyclopedia of knowledge, but an encyclopedia of that which is verifiable. I'm sick to my stomach and ALARMED to learn that so many Americans have been tricked and trapped into believing that TRUTH is not VERITY. Especially since this Wikipedia effort was launched to open the way for the free exchange of knowledge. You people, having taken over the effort through subtlety, are proving to be a CLEAR and PRESENT danger. If my concern is not warrented, I suggest you open an editorial chain of command for original contributions that claim to be self-evidently true.—Preceding unsigned comment added by 66.81.191.38 (talk) 04:10, 20 October 2007 (UTC) --66.81.190.29 19:10, 22 October 2007 (UTC)
- Uhm, maybe this is just too obvious, but isn't this entire entry made up original research? There isn't a single source sited on it. If the Leavenworth arrangement works, then it is just a valid as all the other unsited information on this page. Siting sources is important but there isn't there some allowance for the duh factor? Should the number 10 entry and all its occurrences be removed from wikipedia because there are no references sited? Does someone need a reference to say the sky is Azure on a clear bright day? Come to think of it, there are no references to indicate user:VanBurenen even exits, or user:MarkLeavenworth, or myself for that matter. We need to all be deleted from wikipedia promptly. —Preceding unsigned comment added by 76.191.180.179 (talk) 10:30, 29 February 2008 (UTC)
[edit] Pulleys
Pulleys are the same as as a simple machine and also a grooved wheel.
The End
By:Francia Mejia —Preceding unsigned comment added by 69.204.238.130 (talk) 01:51, 20 November 2007 (UTC)
it is a good & easy thing to do in mechanicl progect —Preceding unsigned comment added by 62.139.251.67 (talk) 20:22, 6 December 2007 (UTC)
