If we can ignore the left most track ('cos it’s plain boring…).
In the UK if we were travelling from the camera to the far distance the switch in the middle track would be described as a facing switch.
In the direction of travel any switch that provides a choice of route without stopping and reversing (by providing diverging routes) is called a Facing Switch.
Okay, so if we were to take the curved track of the switch to the right we would then “Trail” through the Trailing Switch in the right hand track.
In the direction of travel any switch that does not provide a choice of route ahead (because routes are converging in the direction of travel) is called a Trailing Switch.
A Facing Switch ALWAYS has to be set for the route to be travelled over.
A Trailing Switch will normally be set for the route to be travelled over BUT, mostly in yards, some can be pushed through (the leading wheel flanges will shove the blades to the necessary position).
At the exit end of some loops the switch that provides the trailing connection back into the main is fitted with a spring mechanism. These switches will normally be held open for the main route by the spring. When a train is to leave the loop each set of wheel flanges will shove the blades out of their way. After each wheel flange the spring will return the blades to the closed position against the stock rail.
(In order for anything to move into the loop in the facing direction at a switch of this kind the blades have to be forced over and held against the action of the spring).
On a model I have seen a hidden loop worked with a spring switch at each end. Each switch was set by its spring for the left hand route on approach, . this way trains crossed automatically.
in the USA when you approach a switch from the end with the points it is a facing point switch. if you approach from the frog end it is a trailing point switch. so it depends on which way you are going
when i was a signal maintainer i worked on the only spring switch that the NYCTA had. it was basically a hand throw switch with a hydrolic cylinder filled with springs and hydrolic fluid. when the train approached the switch from the frog end the wheels would push sideways on the rail directly before the point and it would push on a rod and a crank to pull the locking bar out of its position. the wheels would then push over the point. when the train completly passed over the switch the points would be pushed back to their original position by the hydrolic cylinder and locked by the locking bar. the train then would reverse direction and pass over the switch again to go onto the car wash racks. well several times the train stopped without passing over the switch completly due to human error and then reversed direction with the result of knocking down the wash racks and derailing. twenty years ago that switch was supposed to be replaced with a regular power switch but it’s still there.
as for your previously long post about slip switches. a single slip allows a train to cross from one track to two other tracks and a double slip lets a train on a second track follow the same route. they are used mainly to save space that would not have allowed the installation of double end crossovers.
by the way. i was able to view the pictures by ignoring the not found text and clicking on the tower link then clicking on santa clara tower when it appeared.
David, although there a number of railroad terms that have different names between UK / Europe and North America, the ones you have mentioned above are very much the same.
I couldn’t see the picture, but I got the jist from your description. Technical tip: use the preview reply button, then test the link by clicking on it , before posting.[;)]
The problem with the link is that it is split in two. If you stick it back together (I copied the second line, clicked the link, then pasted it back on) it works.