Talk:Linkage (mechanical)

Gruebler's equation

Grueblers equation - there is inconsistency between labels used on the diagram (there is a "j") and that in the equation (there is an "f"). Not being an engineer I do NOT know which is the standard terminology so for now I won't try to correct it, but could somebody please give it a go? --VivaEmilyDavies 17:24, 2 Mar 2005 (UTC)

Thanks, the image is now fixed to match the formula. Note: it's a simplified version of the formula, I thought this was best for the article. -- Duk 17:57, 2 Mar 2005 (UTC)

Thanks! If this is a simplified version of Gruebler's Equation, then I think that the formula should have an article of its own right. --VivaEmilyDavies 18:16, 2 Mar 2005 (UTC)

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the link: MIT Open Course ware, Matlab code for four bar linkages no longer goes any where.... cheers and thaks —Preceding unsigned comment added by 121.219.149.221 (talk) 07:44, 27 October 2007 (UTC)

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could anyone help me out in drawing velocity diagrams and accceleration diagrams easily  ? Sharath, hyderabad —Preceding unsigned comment added by 117.195.226.38 (talk) 13:57, 22 January 2008

Toggle mechanism

I added a brief discussion of toggle mechanisms and removed the missing information tag. I have also rewritten the introduction to be more accurate. I would like to make additions that make this article interesting and useful. Prof McCarthy (talk) 03:43, 12 June 2011 (UTC)

It currently has "Toggle mechanisms are four-bar linkages […], but in Switch#Toggle switch, there is "The word "toggle" is a reference to a kind of mechanism or joint consisting of two arms, which are almost in line with each other, connected with an elbow-like pivot.". So, which is it? And some sources would be welcome. Thanks in advance --Jerome Potts (talk) 21:12, 26 June 2013 (UTC)

Oh, and here are two illustrations available:

• 
• 

--Jerome Potts (talk) 21:47, 27 June 2013 (UTC)

Neither of those are really useful - especially not the first - as there's no room for any over-centre action in the linkage. "Toggle linkage" has two meanings: toggle press and self-locking toggle clamp. These are both the press form: force downwards on the centre gives an increasing force sideways. The more common form though is where a toggle is allowed to go past the centre point, thus becoming self-locking. Andy Dingley (talk) 22:34, 27 June 2013 (UTC)

Toggle linkages are substantial enough that we could spin off a whole separate article about them.Andy Dingley (talk) 22:37, 27 June 2013 (UTC)

So, about the "toggle switch", which is it ? The self-locking kind, since i don't suppose that it's the toggle press ? --Jerome Potts (talk) 21:08, 28 June 2013 (UTC)

Open-framed toggle switch

It's a toggle latch, although a rather different mechanism. It has the same "toggle action" in effect but not really much in common about how it does so. Switches don't need a high contact force and they must have a low operating force. So rather than a four-bar linkage where the toggle action depends on an 'impossible' over-centre (assuming incompressible links), switches use an easily compressible coil spring in one of the links.

The first 'toggle' switches were tumbler switches for domestic lighting, which haven't been installed in the UK for something like 40 years, but are still starting fires across America today. These are a pressbutton leaf switch (press a springy brass strip down onto another contact), but with a toggle mechanism above them. The tumbler lever (the bit you touch) toggles to one side or the other, and there's a cam lobe on its base to press the contacts down.

Later toggle switches (illustrated) have a positive action for both connect and disconnect (although they're not necessarily forced-break switches). The same toggle action is used, but instead of pressing onto a sprung leaf (which can stick shut), they move a conductive bar from side to side. Andy Dingley (talk) 21:45, 28 June 2013 (UTC)

Modifications to Linkage article

I have modified the introduction moved the figures around and added the scissor lift picture and the animation of Watt's linkage. I removed the flyball governor, because even though it is a linkage it is more important to control theory and mechanical systems. I hope these changes are acceptable Prof McCarthy (talk) 04:40, 12 June 2011 (UTC)

I have moved the uses section above the history, included a discussion of the lever and edited the wording somewhat. I also added the top figure of an adjustable crank engine. I would like to make more edits of this type to help with the presentation. Prof McCarthy (talk) 20:35, 13 June 2011 (UTC)

Section on History

I would like to rewrite the section on history. It is currently written with general statements that I believe I can make more precise. You can see an editorial that I have written on the topic at the link JMR Editorial. Prof McCarthy (talk) 06:16, 14 June 2011 (UTC)

Your recent additions have generally improved the quality of this article. Keep up the good work! Reify-tech (talk) 06:30, 14 June 2011 (UTC)

I think that the 2 original sentences you removed at the end of the "History" section were relevant to the history of linkages, their historical use, and recent changes in their application. Perhaps they could be reworded better? By the way, as a minor note, I think the Wikipedia citation templates add a superfluous space at the end of each cite. This causes the footnote flags to look like this: "blah blah blah. [23] [24] [25]". The extra spaces can easily be removed manually, once one realizes where they are coming from. Also note, "Where footnotes (ref tags) are adjacent to most punctuation,[4] such as a comma or period, place them after the punctuation, with no intervening space" (MOS:PAIC). I would clean these up, but I don't want to cause an "edit collision" with your work (Wikipedia currently does not implement advisory or mandatory lockout of simultaneous editing). Last but not least, at the head of the "History" section, is there a distinction between "Achimedes" and "Archimedes", or is it a typo error? Anyway, the article looks better by the day, so press onwards! Reify-tech (talk) 14:37, 15 June 2011 (UTC)

Also note that the Wikipedia Manual of Style recommends "logical punctuation" (British, rather than traditional American style) in the placement of quotation marks (MOS:LQ). In addition, the MOS recommends using italics for titles of books and other major works, and also titles of periodical publications (MOS:TITLE). These are relatively minor points, but I wanted you to know them, since you're editing a lot of new material. Reify-tech (talk) 15:07, 15 June 2011 (UTC)

Thank you very much for your advice. As you must see from my many minor edits, I am plagued by the fact that my fingers do not seem to do what I think they are doing. Prof McCarthy (talk) 20:01, 16 June 2011 (UTC)

bicycle linkage

It says to clarify on the bicycle linkage efficiency: if its moving in a tight arc, on compression/expansion it will create motion on the forward-backward axis in the bike components, which will needlessly move weights in/on the bicycle to/from each other, wasting energy. Having the larger arc reduces this displacement. It is kind of similar to the left-right motion concern with the panhard rod, but because that is forcing a left-right motion there is no additional difficulty going uphill with it. This is my deduction, I have no reference as this site requires.Charlieb000 (talk) 05:45, 11 June 2017 (UTC)

Spelling, etc.

right: M = 6(N − 1)

wrong: M=6(N-1)

wrong: M=6(N-1)

In this context,

• One italicizes variables but not digits and not parentheses or other punctuation and not things like cos, max, det, ln, etc.
• A minus sign is not a stubby little hyphen.
• Proper spacing is used.

This is all in WP:MOSMATH. 2601:445:437F:FE66:21B9:9BD:356B:3C15 (talk) 17:26, 23 April 2018 (UTC)