Car-coup′ling.
（
Railway.) A device for connecting the cars in a train.
In the
United States this is usually a form of shackle, but in
Europe the connection is more intimate, the cars being coupled together so firmly as to prevent the jar as the cars collide or jerk apart in stopping and starting.
This mode of coupling is also found in many
United States railways, especially where the steam or air brakes throughout the train are operated by the engineer.
The English car-coupling (
Fig. 1107,
A) is a right and left screw-shackle,
a on the median line making a connection sufficiently rigid to somewhat compress the
buffers b b on each side.
In some cases the
buffers of adjoining cars are connected by chains, and their rods act as pistons in tubes provided with springs; the cars are thus coupled by the buffers.
The
draw-bar d of the coupling is connected to an elliptic spring
e, which diminishes the jerk of the cars when starting the train.
Some of these features are also found in
B, which is an old form of
United States coupling with buffers, copied from the
English, from whence we early received our railway engines and cars.
The drift is now the other way across the
Atlantic.
C C′ are respectively plan and elevation of the
Miller coupling, which connects automatically as the respective point-headed hooks come in collision.
A sufficient amount of lateral play is allowed to the hooks
a a to allow the wedge-shaped surfaces to slip past each other, and springs
b b at the rear of each keep them in engagement when once connected.
Special means are used to withdraw the hooks from each other when they are to be uncoupled.
The lower view,
C′, shows the mode of engagement less clearly, but exhibits also the spring buffers
c, above the hooks, which act as fenders to the cars, and deaden the blow as the cars surge against each other in checking the speed of the train.
The couplinghooks themselves have also springs
d for the same purpose.
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Car-couplings. |
In
Fig. 1108,
D is a falling latch-hook.
E has a gravitating hook
a, with a spring which allows it to yield to the thrust of the entering link
b in the act of coupling.
On the back of the hook
a is a handle
c, which is lifted to uncouple the link.
F has a vertically sliding bolt, which rises automatically as the link collides with its lower inclined portion when coupling, and then falls down into engagement.
G shows a pair of draw-heads in which the tumbling-latch
a holds up the pin until thrust back by the entering link.
The pin
b, when fixed for automatic coupling, rests on the toe of the latch, as in the left-hand draw-head; the link pushes back the latch and allows the pin to drop from the toe, as in the right draw-head.
H H′ are two draw-heads, showing the respective positions of the uncoupled and coupled pins
a a. In the former, the left of the figure, the pin
a rests on a sliding latch, which will give way before the thrust of the link
d, — a result already accomplished in
H′, the right-hand figure.
I I′ are two matching draw-heads, corresponding in essential respects with the one just described; sliding pistons holding up the link and retiring before the thrust of the entering link.
[
467]
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Car-couplings. |
J has a double feature.
A plate to hold the projecting link
a in coupling position, and a small sliding-latch
b above, to hold the coupling-pin
c, which is dropped, when the draw-heads come into actual collision and thrust in the latch.
K has a ball
a, which holds up the pin, and rolls away before the thrust of the link
b, allowing the pin to drop.
In
Fig. 1109 L has the arrow-head bolt
b, which is a substitute for the usual link, and is grasped between the pair of jaws
a a, which spring apart to receive it. The arrow-head form of coupling has many variations, which principally concern the modes of retention.
M has a bar with two slots instead of two heads, the bar being shown separately at
m. As the end of the bar
m enters the draw-head, it thrusts up the gravitating-latch, which immediately falls into the slot of the bar. To uncouple the link, the latch is lifted by a lever above.
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Car-couplings. |
N is a plan view of a coupling in which each drawhead has a link which couples over a horn on the corresponding draw-head of the other car. A pin in each case prevents accidental disengagement.
O is an elevation of a pair of draw-heads, each of which has a link which may be coupled over a horn on the other.
P has a two-horned tumbler, one of which carries a link
a which may be the means of coupling to a corresponding draw-head, and the other forms a latch for a link
a′ proceeding from the other draw-head.
Kendall's English patent, April 17, 1841, describes an elastic coupling which retains its hold while the pull is direct, and becomes detached when the pull is oblique, by reason of one of the carriages leaving the track.
This feature has formed the subject of many
United States patents.
