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Uncoupling levers - How do they work

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Posted by nbrodar on Friday, March 9, 2007 9:16 AM

 selector wrote:
Should I conclude that there is a sort of two-part action to the releasing of the knuckle?   If the releasing lever is lifted only so far, the power could pull away and the knuckle should open.  If I were to pull the lever even further, the secondary action should actually encourage the knuckle to open if there is nothing to prevent its swing....is that right?  So there is a cam, of sorts, that forces the knuckle to open? 

Back to the topic at hand...

The motion is one and the same.  There's only one way pull on the lever - all the way up. 

The slack must be in, to be able lift the cut lever and raise the lock.  If there is tension on the knuckles, the lock won't release.

There is usually enough play in the knuckles for the knuckle thrower to move the knuckle slightly.   If you look down at the coupled knuckles while you "pull the pin" you can acutally see the knuckle jiggle, as the thrower tries to open the knuckle.  When there is nothing coupled to the car, the motion is more pronounced.

Nick

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Posted by selector on Friday, March 9, 2007 12:02 PM
Thank-you, Nick.
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Posted by TomDiehl on Friday, March 9, 2007 12:42 PM

 marknewton wrote:
So what are you disputing? That these parts exist, or what they are called?

YOU are the one disputing the fact that it's called "pulling the pin" here in the US. So the part that you "pull" when you pull the uncoupler lever is the "pin."

Smile, it makes people wonder what you're up to. Chief of Sanitation; Clowntown
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Posted by marknewton on Friday, March 9, 2007 4:13 PM
No, Tom, you're wrong, I dispute no such thing. But until you learn to read for comprehension there's no point continuing.
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Posted by wjstix on Friday, March 9, 2007 4:17 PM

Perhaps this page at the Pacific Southwest Railway Museum will help explain the point about the 'pin'...referred to there as "the locking pin":

http://www.sdrm.org/faqs/couplers/  

Be sure and check out the video demonstration too!!  Cowboy [C):-)]

 

Stix
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Posted by marknewton on Friday, March 9, 2007 4:41 PM
Very helpful - a simplified explanation for a non-technical audience. The part referred to as a "locking pin" is the lock lifter.
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Posted by TomDiehl on Friday, March 9, 2007 4:41 PM

You're right, there is nothing to dispute, your original statement says it all:

 marknewton wrote:
There is no "pin that keeps the knuckle closed". Pull a knuckle coupler apart and you'll find a lock, a lock lifter, and a knuckle thrower.

Smile, it makes people wonder what you're up to. Chief of Sanitation; Clowntown
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Posted by wjstix on Friday, March 9, 2007 5:02 PM

 marknewton wrote:
Very helpful - a simplified explanation for a non-technical audience. The part referred to as a "locking pin" is the lock lifter.

...which looks a great deal like the "pin" from a link-and-pin coupler, which is why it's been called "the pin" for 100 years or so by US railroaders (but maybe not by Aussie "railwaymen"??Big Smile [:D])

Bottom line is, if you took fifty US railroaders and asked them to show you a car's lock lifters, you might get one guy who could point it out and 49 blank stares. Ask them to show you the pin and they'd all know it's the part that opens the coupler when they lift the cut lever. 

Stix
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Posted by Anonymous on Saturday, March 10, 2007 12:07 AM
 wjstix wrote:

 marknewton wrote:
Very helpful - a simplified explanation for a non-technical audience. The part referred to as a "locking pin" is the lock lifter.

...which looks a great deal like the "pin" from a link-and-pin coupler, which is why it's been called "the pin" for 100 years or so by US railroaders (but maybe not by Aussie "railwaymen"??Big Smile [:D])

Bottom line is, if you took fifty US railroaders and asked them to show you a car's lock lifters, you might get one guy who could point it out and 49 blank stares. Ask them to show you the pin and they'd all know it's the part that opens the coupler when they lift the cut lever. 

Railroaders are more than just those in train service.  Which department are your 50 railroaders drawn from?  Operating or mechanical?  I started out 30 years ago in engineering, moved to mechanical, moved to operating, was moved to signal, and now I've been moved into network planning and capacity design.  There's slang and there's proper terminology.  Mark Newton quotes the manual, that's good enough for me.

S. Hadid

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Posted by Eddie_walters on Saturday, March 10, 2007 7:44 PM

http://www.google.com/patents?vid=USPAT4363414&id=cvQ4AAAAEBAJ&printsec=abstract&zoom=4&dq=4363414#PPP1,M1

Here's the full patent with some nice cross sectional diagrams of the internal mechanism of the coupler. The lock doesn't look like a pin to me!

Tom - Mark isn't disputing the venacular form used by railroaders. He's disputing what the part is actually called. The patent is by the inventor, so I'd say that is pretty authoritative.

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Posted by GMTRacing on Saturday, March 10, 2007 8:50 PM

Or the original from 1923

http://www.google.com/patents?vid=USPAT1475634&id=vlhqAAAAEBAJ&dq=1475634&jtp=1#PPA20,M1

although I must admit we do call it pulling the pin, not freeing off the lock or some such.Sign - Dots [#dots]J.R.

 

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Posted by TomDiehl on Saturday, March 10, 2007 9:57 PM
 Eddie_walters wrote:

Tom - Mark isn't disputing the venacular form used by railroaders. He's disputing what the part is actually called. The patent is by the inventor, so I'd say that is pretty authoritative.

Actually, yes he is disputing that. Look at the first and second posts on the first page of this thread. User "jsoderq" posted the answer to the original question using the common terminology you'd find railroaders in the US use in everyday operations.

Mark answered him stating that "There is no "pin that keeps the knuckle closed". Pull a knuckle coupler apart and you'll find a lock, a lock lifter, and a knuckle thrower."

I was the first of several posters here to point out to Mark that "pin" is the common or slang terminology used in the US, probably dating back to the link-and-pin days. If you tell a railroader today to "pull the pin" he/she would know you want to uncouple cars, so logically they would refer to the part the uncoupling rod lifts in the coupler as a "pin." Obviously, he can't grasp this.

Smile, it makes people wonder what you're up to. Chief of Sanitation; Clowntown
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Posted by marknewton on Sunday, March 11, 2007 8:28 PM
As I wrote earlier Tom, learn to read for comprehension. The only person having difficulty grasping the concept is you. The original question asked how the coupler functioned, not what the slang term for opening it was. But you still can't get it...
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Posted by TomDiehl on Sunday, March 11, 2007 8:35 PM

 marknewton wrote:
As I wrote earlier Tom, learn to read for comprehension. The only person having difficulty grasping the concept is you. The original question asked how the coupler functioned, not what the slang term for opening it was. But you still can't get it...

Since I'm not the only one to point that out to you, it seems the "comprehension" problem started with the writing.

Smile, it makes people wonder what you're up to. Chief of Sanitation; Clowntown
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Posted by marknewton on Monday, March 12, 2007 7:28 AM
 Eddie_walters wrote:

Tom - Mark isn't disputing the venacular form used by railroaders. He's disputing what the part is actually called. The patent is by the inventor, so I'd say that is pretty authoritative.


So would I - but apparently Tom knows better than the rest of us, who only run, fix or build trains for a living. He seems unable, or incapable of understanding my original point - it is not the so-called "pin" that keeps the knuckle closed, it is the lock.

Cheers,

Mark.
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Posted by wjstix on Monday, March 12, 2007 7:59 AM

Well OK let's take a look here...the original question asked what uncoupler levers - a detail part commonly added to model freight cars - did. The first answer said that by pulling up the lever, you pulled a pin out of the coupler that opened the coupler. That is correct, but the way the answer was phrased, it did sound like they were saying the 'pin' was what held the coupler closed, rather than being the device that caused the coupler to open.

So the actual thing that holds the coupler closed is a "lock" that is activated by the pin to open it(??) Note that the cited patent application does refer to a "pin" being part of the coupler.

So we were basically talking about two different things. The pin is different from the lock, but both are part of the coupler.

 

Stix
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Posted by TomDiehl on Monday, March 12, 2007 8:27 AM
 marknewton wrote:
 Eddie_walters wrote:

Tom - Mark isn't disputing the venacular form used by railroaders. He's disputing what the part is actually called. The patent is by the inventor, so I'd say that is pretty authoritative.


So would I - but apparently Tom knows better than the rest of us, who only run, fix or build trains for a living. He seems unable, or incapable of understanding my original point - it is not the so-called "pin" that keeps the knuckle closed, it is the lock.

Cheers,

Mark.

Actually Tom does run and especially fix the real thing. The thing that Mark can't seem to grasp is the US slang term for uncoupling being "pull the pin." Whether some design engineer has another term for it is irrelevent, an operating railroader calling it the "pin" is not incorrect.

Smile, it makes people wonder what you're up to. Chief of Sanitation; Clowntown
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Posted by TomDiehl on Monday, March 12, 2007 8:31 AM
 wjstix wrote:

Well OK let's take a hook here...the original question asked what uncoupler levers - a detail part commonly added to model freight cars - did. The first answer said that by pulling up the lever, you pulled a pin out of the coupler that opened the coupler. That is correct, but the way the answer was phrased, it did sound like they were saying the 'pin' was what held the coupler closed, rather than being the device that caused the coupler to open.

So the actual thing that holds the coupler closed is a "lock" that is activated by the pin to open it(??) Note that the cited patent application does refer to a "pin" being part of the coupler.

So we were basically talking about two different things. The pin is different from the lock, but both are part of the coupler.

 

The "pin" that seems to confuse Mark is the pivot pin for the knuckle. This is not the "pin" that US railroaders refer to when they "pull the pin." "Pin" in this case is a slang term that's a holdover from the old days.

Smile, it makes people wonder what you're up to. Chief of Sanitation; Clowntown
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Posted by marknewton on Monday, March 12, 2007 8:56 AM
 TomDiehl wrote:

Actually Tom does run and especially fix the real thing.



But not for a living...

Why this obsession with the phrase "pull the pin?" You've harped on this straw man argument now for three pages, when no-one, least of all me, ever disputed it? Or is this the sum total of your knowledge?
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Posted by TomDiehl on Monday, March 12, 2007 9:05 AM
 marknewton wrote:
 TomDiehl wrote:

Actually Tom does run and especially fix the real thing.



But not for a living...

Why this obsession with the phrase "pull the pin?" You've harped on this straw man argument now for three pages, when no-one, least of all me, ever disputed it? Or is this the sum total of your knowledge?

It's your obsession with stating that calling it a "pin" is wrong. We could say this is an example of your sum total of knowledge of US terminology (from down under) used by every day railroaders.

Smile, it makes people wonder what you're up to. Chief of Sanitation; Clowntown
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Posted by marknewton on Monday, March 12, 2007 9:09 AM
 TomDiehl wrote:

The "pin" that seems to confuse Mark is the pivot pin for the knuckle.



Good grief! Where did you get that idiotic idea from? I never mentioned the knuckle pivot pin, since it is not relevant to the original question. When are you going to address the things I've actually written, instead of the things *you think* I'm confused about?

This is not the "pin" that US railroaders refer to when they "pull the pin." "



No, it isn't, but then no-one other than you claimed otherwise. I sense another strawman argument in the making.

Let's try one more time. When US railroaders talk of "pulling the pin", it's the lock lifter they are operating. It in turn operates the lock, WHICH IS WHAT KEEPS THE KNUCKLE CLOSED...
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Posted by marknewton on Monday, March 12, 2007 9:35 AM
 TomDiehl wrote:

It's your obsession with stating that calling it a "pin" is wrong.
We could say this is an example of your sum total of knowledge of US terminology (from down under) used by
every day railroaders.



Poor old Tom, madly flogging a dead horse.

You demonstrated your ignorance of Australian usage with your earlier comment about "carriges". And you demonstrated your lack of comprehension with your repeated assertion that I wrote calling it a pin is wrong. I've never done that. What I've repeatedly written is that saying the "pin" keeps the knuckle closed is wrong - big difference for those capable of understanding it.

And for what it's worth, Australian train crew also use the phrase "pulling the pin" - have done for about fifty years. But those "down under" train crew know it isn't the "pin" that keeps the knuckle closed...

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Posted by TomDiehl on Monday, March 12, 2007 9:48 AM
 nbrodar wrote:

"Pulling the pin" is slang for operating the cut lever.  It's a hold-over from the days of link and pin couplers.

Nick

It looks like a "real railroader in the US" would disagree with you.

Smile, it makes people wonder what you're up to. Chief of Sanitation; Clowntown
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Posted by el-capitan on Monday, March 12, 2007 10:08 AM

I think that the point here is, the term "pulling the pin" has absolutely nothing to do with operating a knuckle coupler, it is just a slang term for uncoupling cars. It's just like the term "the whole nine yards" which refers to ammunition and going through an entire gun belt which happened to be 9 yards long (please don't argue origins of this, it's just what I heard). If I were to say that I went through the whole nine yards, I am not necessarily talking about ammo, I could be talking about how much milk I drank. This is not used as a literal phrase.

"Pulling the pin" is an american term still used today. However, it has not been a literal term since the days of the link and pin. When you pull the uncoupling lever you are not pulling a pin. The pin in a modern coupler is located in the knuckle and works as a hinge mechanism to allow the knuckle to pivot. It does not lock the knuckle in place.

And as for railroad employees calling it a pin, if they do, that really doesn't mean anything. Operators of equipment often do not know the technical terms for items they are using everyday. Just because a brakeman or many brakemen or all brakemen think that it is still a pin they are pulling, doesn't necessarily make it a pin.

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Posted by selector on Monday, March 12, 2007 2:18 PM

Okay, I'm calling both of you principals out. Mischief [:-,]

Any fool can tell that if you pull that long thingy that holds the two main knuckle parts together, you know, the one that allows the front curved part to swing open, the knuckle will fall apart.  It's like pulling the pin on a door hinge, for crying out loud!

(pauses for effect...) Whistling [:-^]

(umm, no one's laughing....) Sigh [sigh]

I guess you had to be there.

I wish you all a good day, gents.

-Crandell

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Posted by BigJim on Tuesday, March 13, 2007 6:11 AM

Call the parts anything you like.

When you uncouple cars, it's still called "Pullin' the pin"! A term that can also be used when refering to "marking off".

.

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Posted by marknewton on Tuesday, March 13, 2007 6:51 AM
 TomDiehl wrote:
 nbrodar wrote:

"Pulling the pin" is slang for operating the cut lever.  It's a hold-over from the days of link and pin couplers.

Nick

It looks like a "real railroader in the US"would disagree with you.



Nice bit of selective quoting there, Dihl. Pity that you had to snip the bit that supports my position. But the full quote from Nick Brodar not only confirms my original point, but also mentions a component you claim doesn't exist in US couplers, which makes me wonder how much you actually know, as opposed to what you claim to know. Add the posts from 1435mm and jeffhergert, and it looks like 3 "real railroaders" in the US agree with me.

You laughably claim that you fix trains - next time you re-assemble a knuckle coupler, leave the lock and knuckle thrower out. See whether the lock lifter - the "pin" you are so enamoured of - keeps the knuckle closed, or opens it when "pulled".

plonk!
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Posted by TomDiehl on Tuesday, March 13, 2007 9:17 PM
 marknewton wrote:
 TomDiehl wrote:
 nbrodar wrote:

"Pulling the pin" is slang for operating the cut lever.  It's a hold-over from the days of link and pin couplers.

Nick

It looks like a "real railroader in the US"would disagree with you.



Nice bit of selective quoting there, Dihl. Pity that you had to snip the bit that supports my position. But the full quote from Nick Brodar not only confirms my original point, but also mentions a component you claim doesn't exist in US couplers, which makes me wonder how much you actually know, as opposed to what you claim to know. Add the posts from 1435mm and jeffhergert, and it looks like 3 "real railroaders" in the US agree with me.

You laughably claim that you fix trains - next time you re-assemble a knuckle coupler, leave the lock and knuckle thrower out. See whether the lock lifter - the "pin" you are so enamoured of - keeps the knuckle closed, or opens it when "pulled".

plonk!

Actually, it supports my position if you can actually comprehend what you read. Regardless of whether you want to call it a lock or a pin that you pull with the uncoupling lever, it will still release the coupler knuckle to open.

You laughably claim you know what you're talking about when all you can quote is a diagram from the internet for your terminology. The only time it matters is when you're ordering parts, and yes, I do fix trains. If you'd care to read my profile you'd find I'm part of the crew restoring the K4 at Steamtown, and the restoration crew at the East Broad Top railroad, more experience than just a "driver." But with the comprehension skills you've displayed so far, that still probably wouldn't help.

Smile, it makes people wonder what you're up to. Chief of Sanitation; Clowntown
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Posted by TomDiehl on Tuesday, March 13, 2007 9:18 PM
 BigJim wrote:

Call the parts anything you like.

When you uncouple cars, it's still called "Pullin' the pin"! A term that can also be used when refering to "marking off".

And another railroader heard from, with the complete statement quoted.

Smile, it makes people wonder what you're up to. Chief of Sanitation; Clowntown
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Posted by Eddie_walters on Wednesday, March 14, 2007 5:15 PM

So, really - this whole dispute is about nothing.

I think that everyone agrees that railroaders use the term "pulling the pin" in reference to uncoupling cars.

I think that everyone agrees that despite the wording of the above phrase (which apparently dates back to the days of link and pin couplers), that in a type E coupler the part is actually called a "lock", not a "pin", the pin being the pivot for the coupler.

So... what's the problem?

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