Stean loco vacuum brake query

[102 fan]

On a steam loco's vacuum brake in the cab, there's a disk with holes which travels through 90 degrees, this I know operates the large and small ejector cones. My query is about the small finger operated lever that is on the handle - what does that operate?

It's on the last pic on this link - http://www.engrailhistory.info/r143.html


Thanks

 

[bronzeonion]

I was under the impression that small finger operated lever was just to release a catch so you can pull the main lever, like how a signal lever works. I can't see the picture you have linked because im on my phone so if it's something else you're talking about then sorry

 

[455driver]

It's on the last pic on this link - http://www.engrailhistory.info/r143.html

I didnt get past the picture on the homepage, sorry!

 

[John Webb]

Neither could I see the picture you were talking about.

From the "Handbook for Railway Steam Locomotive Enginemen", originally published for BR and first reprinted by Ian Allan in 1977 and on other more recent dates, I think you are looking at the 'Dreadnought' ejector? If so, then the small handle controls the flow of steam to the small ejector cone to maintain the vacuum while the train is moving.

 

[102 fan]

Sorry, the page must have died after I linked it! Here's a working link -
http://www.railwaywondersoftheworld.com/part13.html
It's the small finger operated valve attached to lever A.

Thanks

 

[73202]

I can see the original link
It's shown in the BR handbook as the Auxiliary Application Valve. The writeup says it's used for light brake applications to be made for controlling the train speed.

link to drawing
http://home.datacomm.ch/ddupraz/fichiers/Dreadnought_Ejector.pdf

 

[102 fan]

Thanks. It's a lot clearer now!