Is someone having a joke here?

[Brian Harrap]

[The Stationmaster]

I get the impression that it has been partially plain lined.  It presumably (???) was originally some sort of swing nose crossing arrangement part of which survives and part of which (one switch and wing rail) has been replaced with an ordinary length of rail.  Best I can come up with.

 

There's an illustration of a similar sort of swing nose crossing on this wiki page -

https://en.wikipedia.org/wiki/Swingnose_crossing

[Flying Pig]

Isn't the mechanism a moveable ramp to allow passage over the "crossing" on the diverging rail?  The stock rail at the top of the picture forms a matching hump.  I believe I've seen pictures of similar items used in Japan.

[Enjay]

I'd love to know where that photo was taken, Brian?

[Nearholmer]

I’m with FP - that plate flaps over to form a crossing.

 

is it also an outside-flange Railway, and perhaps cable-worked?

 

Great Orme, or similar?

 

(actually, I don’t think it is GO, although their points are a bit odd)

Edited February 29, 2020 by Nearholmer

[Talltim]

I think you are right about the plate. If you look at the far rail, it has a hump which would match the hump caused the the rail on the plate sitting on the rail that is already there (as already said by Flying Pig). until you realise that it makes the perspective look funny.

What I don’t understand is the combination of the checkrail and the swing nose. If it was an inside flange line, they you wouldn’t need the swing nose, if it was outside flange then the checkrail does nothing (should it be on the outside?) The only possibility I can think of is double flanges.

Edited February 29, 2020 by Talltim

[Flying Pig]

17 minutes ago, Talltim said:

What I don’t understand is the combination of the checkrail and the swing nose. If it was an inside flange line, they you wouldn’t need the swing nose, if it was outside flange then the checkrail does nothing (should it be on the outside?) The only possibility I can think of is double flanges.

 

I don't think there is a swingnose.  There is a continuous rail through the crossing on the main route; on the other route, the rails are both fixed, one forming a flangeway for wheels on the main route, the other being bent and welded or bolted in position.

 

It's clearly an inside-flange system, as shown by the flangeway on the main route, with a wingrail purely to guide wheels heading towards the camera into it smoothly.  There's no checkrail on the near side as wheels heading away from the camera on that route  don't have to negotiate a flangeway gap and crossing nose.  That's the point of the design - providing uninterrupted passage for wheels on the main route.

 

There is a checkrail on the far side,  as wheelsets need to be guided where they run over the ramp on their flanges and don't get the usual guidance through the crossing.

[Nearholmer]

You are right about it being for ordinary, inside flanges; the checkrail dawned on me after I'd typed.

 

Low speed operation? Tramway or industrial?

 

The bit I don't get is: why hinge the plate, rather than leave it in position all the time?

 

As shown, nothing can traverse it by either route, unless wheels on the leftward route simply clonk there way across, riding on the flange-tip through where the crossing isn't.

 

I don't think the plate has two positions, unless there are bits we can't see.

 

Part of a weirdly devious trap-point, shown in the trapping position, the plate flapping over only when in the through position - therefore don't worry about the clonking?

 

Are there actually two separate flaps, one for each route?

 

 

[Talltim]

I now think Flying Pig is right and it’s not a swing nose, rather just a hefty section to bolt the rails together. 
In which case the rest of what he says makes sense re inside flanges

Nearholmer, the ‘main’ route has no crossing to cross, it’s essentially plain track.

The question is, as it functions the same as a standard point, and there’s no weird flange position, why not just use a standard crossing?

Edited March 1, 2020 by Talltim

[Flying Pig]

 

1 hour ago, Nearholmer said:

As shown, nothing can traverse it by either route, unless wheels on the leftward route simply clonk there way across, riding on the flange-tip through where the crossing isn't.

 

 

Yes it can - there is a flangeway for the rightward route and as Talltim says it's essentially plain line in that direction. 

 

As to why, presumably for smoother running on the main route where the diverging route is slow and infrequently used.  Also no crossing nose to wear.  Googling "jump frog turnout" brought up some information on similar designs, but nothing with the moving ramp unfortunately.

[PatB]

The perspective is a little confusing. It took me a couple of looks to realise we're looking from the toe of the points towards the diverging end. It makes the arrangement of wing/check rails make much more sense. 

[Nearholmer]

Ah!

 

I was seeing it as if we were looking towards, not away from the switch-tips!

[jim.snowdon]

It's what, in tramway circles, known as an unbroken main line crossing, or in simple terms, a bump over crossing. They aren't uncommon, although much less so than they used to be. The object is to avoid the wear and tear of the crossing where the diverging route is only rarely used. Emergency crossovers were good candidates. 

 

Jim 

[Brian Harrap]

17 hours ago, Enjay said:

I'd love to know where that photo was taken, Brian?

Don't know where exactly, but definitely Japan

B