How is a coupler released? From pictures I can't see any obvious release mechanism or a handle that says "pull here to release". Also..I've watched switching...a train would back up slowly and then stop...but the last car or two would uncouple and keep rolling...is the engineer somehow able to uncouple cars from the locomotive?
Couplers are uncoupled by a cut bar, which is accesable from the side steps on all railcars and locomotives. When you lift the lever on the bar, it rotates and lifts the pin out of position on the coupler, allowing the knuckle to move. The bar is accesable from the side steps of railcars and locomotives, allowing a brakeman/conductor to "kick" cars by uncoupling them while moving.
If nobody was riding the car (even on the other side) when they let the car roll, then they could have uncoupled when they stopped and shoved the cars with the couplers closed and not coupled, shoving the car forward until the engineer throttled down and the car kept rolling.
Here's a photo of the cut bar, which is white and has a yellow-ish bar connected to the pin on top of the coupler. It's circled in red.
I was going to reactivate/ resurrect the ''Knuckle Coupler'' thread from April- Augsut 2007 shortly anyway, so this is an opportunity to start on that - it's at -
http://cs.trains.com/trccs/forums/t/93193.aspx?PageIndex=1
- PDN.
Couplers have a locking pin which holds the knuckle in the closed position. The pin is held in place by gravity and is lifted using the "cut lever" to allow the knuckle to turn.
This group of pictures, etc from the San Diego Railroad Museum will probably do a better job of illustrating it than I can.
As for kicking cars (or humping them, for that matter), the brakes can be "bled off" so that a car essentially has no automatic brakes. The handbrake will be used to hold the car if necessary. When kicking cars, the loco does get up a bit of a run, a crewman will pull the cut lever at the appropriate time, and the car will roll on, generally into a line of standing cars. On the hump, gravity provides the "motive power."
The brakes have to bled off because a car which has its charged trainline suddenly broken (by the parting gladhands) will go into emergency and stop.
I have seen pictures of a locomotive (probably a switcher) which had a pneumatic cylinder on the coupler to lift the pin. That would make it possible for the engineer to handle cars without a second person being necessary to lift the pin.
Houston Ed and Carl can certainly give you a more in-depth picture, since that's what they do.
Larry Resident Microferroequinologist (at least at my house) Everyone goes home; Safety begins with you My Opinion. Standard Disclaimers Apply. No Expiration Date Come ride the rails with me! There's one thing about humility - the moment you think you've got it, you've lost it...
Hmm.....I can't seem to find a good picture.
One pulls up on the cut lever, which in turn raises the lock lifter. The lock lifter, lifts the lock, allowing the knuckle to pivot. The action also pushes on the knuckle thrower, which opens the knuckle (sometimes at least).
Normally, once lifted, the lock will stay raised until an impact on the knuckle causes it to fall, thereby locking up the coupler. This feature allows you to kick cars, without having to run next to the car, holding the cut lever up.
Of course if there is no pin holding the knuckle in, it just falls out near your feet.
Nick
Take a Ride on the Reading with the: Reading Company Technical & Historical Society http://www.readingrailroad.org/
Ulrich How is a coupler released? From pictures I can't see any obvious release mechanism or a handle that says "pull here to release". Also..I've watched switching...a train would back up slowly and then stop...but the last car or two would uncouple and keep rolling...is the engineer somehow able to uncouple cars from the locomotive?
Make a fist with both of your hands...then turn the left hand so that the thumb on top and the right hand so that the thumb is on the bottom or vice versa. Now, interlock the two fists placing fingers of one hand inside the fingers of the other hand. That's the basis for a knuckle coupler. Next, as seen in the pictures, assume the hook or swing portion of the coupler is the outer ends of your fingers with a pin on the pivot. When that pin is "down" the knuckle is closed and tight, but when the pin is pulled up, the swing is realeased and the pair "uncouple". The pin has a loop atop connected to a bar which extends to the outside of the car on the opposite side of the facing car (facing the car end, that would be to your left); when the bar is lifted, the pin is lifted. When coupling at least one of the couplers has to be "open" then the force of coupling will drop the pin to lock. I hope one can follow this.
RIDEWITHMEHENRY is the name for our almost monthly day of riding trains and transit in either the NYCity or Philadelphia areas including all commuter lines, Amtrak, subways, light rail and trolleys, bus and ferries when warranted. No fees, just let us know you want to join the ride and pay your fares. Ask to be on our email list or find us on FB as RIDEWITHMEHENRY (all caps) to get descriptions of each outing.
One thing not mentioned so far -
The coupler can't be under significant tension/ pulling when the 'cut lever' and pin are attempted to be lifted - such as when a train stops with the slack 'stretched out' - the friction from the train force bearing on the coupler's pin will be too high for that to be accomplished.
So, that's why more typically the loco will back or push against the car to be uncoupled - even if they're already rolling in the desired direction - to make sure that 'slack' is provided, which is needed to relieve the train forces off of the coupler and its pin so that the pin can then be easily lifted.
- Paul North.
thanks everyone for the excellent responses...
See also the article on ''Couplers - The durable link'', By Kevin P. Keefe, Published: Monday, May 01, 2006, in the 'Railroading Reference', ''ABC's of Railroading'', at:
http://www.trains.com/trn/default.aspx?c=a&id=218
which says, in pertinent part, about 1/3 of the way down the page:
''Cars are uncoupled by lifting a lever that reaches from the coupler to the side of the car, making it unnecessary for a switchman to place himself between cars during coupling. Lifting the lever unlocks the knuckle and lets it swing open, allowing the cars to be pulled away from each other.''
Also note that in the picture Tyler posted there are upward extensions of the cut lever which will allow a crewman to "pull the pin" from the safety of the locomotive steps, even as the locomotive moves away from the car beeing uncoupled. I've used this feature many times.
Paul_D_North_JrThe coupler can't be under significant tension/ pulling when the 'cut lever' and pin are attempted to be lifted - such as when a train stops with the slack 'stretched out' - the friction from the train force bearing on the coupler's pin will be too high for that to be accomplished
A bit off the subject, but when you see the exciting scene in a movie such as Silver Streak which has the hero uncoupling the train from the engine when the engine is pulling for all it's worth, you see something impossible unless the train somehow ran forward faster than the engine and thus put enough slack into the coupling.
Johnny
Deggesty A bit off the subject, but when you see the exciting scene in a movie such as Silver Streak which has the hero uncoupling the train from the engine when the engine is pulling for all it's worth, you see something impossible unless the train somehow ran forward faster than the engine and thus put enough slack into the coupling. Johnny
Near impossible as there is always bunching and pulling. But the real element ovelooked is the brake hose which, when parting, would supposedly stop both parts of the train with the second part hopefully not ramming into the first!
Carl
Railroader Emeritus (practiced railroading for 46 years--and in 2010 I finally got it right!)
CAACSCOCOM--I don't want to behave improperly, so I just won't behave at all. (SM)
tree68Also note that in the picture Tyler posted there are upward extensions of the cut lever which will allow a crewman to "pull the pin" from the safety of the locomotive steps, even as the locomotive moves away from the car beeing uncoupled. I've used this feature many times.
henry6 Deggesty A bit off the subject, but when you see the exciting scene in a movie such as Silver Streak which has the hero uncoupling the train from the engine when the engine is pulling for all it's worth, you see something impossible unless the train somehow ran forward faster than the engine and thus put enough slack into the coupling. Johnny Near impossible as there is always bunching and pulling. But the real element ovelooked is the brake hose which, when parting, would supposedly stop both parts of the train with the second part hopefully not ramming into the first!
In the movie, they uncoupled the F units and first three cars from the rear five cars. If the throttle in the lead locomotive was in run 8 when the train broke in two, wouldn't that have been enough to keep just two engines (still in run 8) and three cars moving the short distance into the train shed and into the station while the rest of the train comes to a stop near the end of the shed? With the speed the train was moving, I would have thought it possible for that to happen. Granted, uncoupling the train at that speed would be very unlikely, although he did struggle with the uncoupling lever for a while before he got it pulled enough to pull the coupler pin.
Kevin
http://chatanuga.org/RailPage.html
http://chatanuga.org/WLMR.html
chatanuga In the movie, they uncoupled the F units and first three cars from the rear five cars. If the throttle in the lead locomotive was in run 8 when the train broke in two, wouldn't that have been enough to keep just two engines (still in run 8) and three cars moving the short distance into the train shed and into the station while the rest of the train comes to a stop near the end of the shed? With the speed the train was moving, I would have thought it possible for that to happen. Granted, uncoupling the train at that speed would be very unlikely, although he did struggle with the uncoupling lever for a while before he got it pulled enough to pull the coupler pin. Kevin
No tellin' what really would have happend except know I wouldn't want to on the train or near the tracks when it did!
.
In the movie they also overlooksd the fact that there was a steam line that would have to be uncoupled as well.
In addition, as soon as the air brake line parted, all of the consist would go into emergency braking. The Pneumatic Control valve in the locomotives' power circuitry would set the engines back to idle and remove power from the motors. The locomotives would stop quickly and the cars behind (if typical of the disk brake systems the GN used) would stop slowly and the train would not break in two. The train would have stayed together even if the coupler pin is pulled.
Another factor was the speed of the locomotives thru any turnouts at the station would easily derailed the locomotive before hitting the end of track buffer.
Kootenay Centralwould also have bottom-operated operating levers.
Yep - gotta remember that on pax cars the pin "drops" up.....
That's why I like to have the coupler on the locomotive open and not on the car.
A stretch never hurts, either.
CShaveRRStretching the joint is something that's always done around here.
I have changed Internet service providers since the coupler thread in 2007, so none of my photos/diagrams show up. I can re-post them here if anyone wishes.
The coupler system we have today is alot safer then to Link/Pin system they had to work with 150yrs ago. Can you imagine trying to guide a link into the pocket and then try and judge when to drop the pin into the hole at the top of the pocket and then trying to get out of the way before the cars came together . Personally I like my fingers just where they are They are orginal equipment Larry
The link hanging in a link & pin coupler housing usually would tilt down so that it would miss the entrance of an opposing coupler housing approaching it for coupling. So trainmen had to hold the drooping link up until it entered the opening of the opposing coupler housing, which by that time would only be about 4”-6” away, and then get their hand out of there before the opposing housings came together.
If the engineer could move very gently, this link holding stunt could come off successfully. But with slack and long cuts of cars, there was always the possibility of an explosive closure of the couplers. Furthermore, the coupler link was rather heavy, so it took the whole hand to hold it up, thus putting the entire hand at risk of being crushed. There were inventions known as safety knives or paddles intended to be used by trainmen for holding up the links during coupling. But trainmen were a tough bunch back in the 1800s, and they somewhat rejected these tools.
And even with a safety knife protecting fingers, there was also the possibility that the coupler heads would bypass each other leaving the trainman’s entire upper body to be crushed by the dead beams on the ends of the cars as they came together.
Even if I had something to hold the link up in the old link-pin couplers, I sure wouldn't want to be standing between two cars as they came together.
More invaluable data, thank you!
"Pull the Pin" meaning to uncouple cars must be one of the oldest railroad terms still in use, going back to mid-19th century link-and-pin couplers.
Our community is FREE to join. To participate you must either login or register for an account.