In the NYC video thread I noticed a view of what looked like a booster in operation on a passenger train.

How does the booster operate? Is there a clutch arrangement so the cylinders are not engaged when the booster is not used?

Thank you for help with Booster 101.

Wesley

Website with some general info on how a booster works:
https://www.railwaywondersoftheworld.com/locomotive-booster.html

Mike,

Thank you for the link. The article was very helpful to understand the history and design of a booster engine.

I still need help understanding the following process.



Is there any jarring action between the gears when the "inter-mediate gear-wheel is moved from the cab by means of a bell-crank through a piston actuated by compressed air?" Or is the booster started when the locomotive is stopped to avoid wear on the gears?

Many thanks for your assistance!

Wesley

I don't have a current link to the ICS 'article' on booster operation, but it had a very complete discussion of operation. It was lesson #2355, which covered the C2 booster design (I am still looking for reference material on the reversible E2 design, which is not clearly illustrated in the Locomotive Cyclopedias I have). At one time there was a digitized list of a great many ICS courses and lessons, which was a tremendous resource.

Note that compressed air is used, and only 'full pressure' control is provided, to make the device simpler for enginemen to use. This was an early example of what would later be termed 'fluidic control' -- a substantial number of things are controlled by nothing more than an on/off lever valve in the cab.

If the gear on the engine does not mesh, the initial rotation of the engine will seat it. There is the chance for a certain amount of 'gnashing of teeth' if the intermediate gear and axle gear are not lined up precisely; the manual notes that this situation will resolve itself within a fraction of a second of driving engagement, at which point the arrangement ought to go into mesh. If it does not, backing down against the slack will drop it in promptly. Power steam admission to the engine is interlocked with gear engagement.

Note that the engine ought to be idled to warm it up. Bypass was provided as noted to allow this. Note that very little steam feed was needed to warm the engine, even with 'no cutoff'.

The later 'reversible' booster allowed the engine to be reversed, not to provide boost with the engine moving backward but in case the idler kick-out action didn't work properly, for example if the engine stalled with the booster engaged. There is, to my knowledge, no positive disengagement 'aid' for the idler, even a Winans-style socket for an assist bar or something. The Swiss or Germans used an idler arrangement to obtain reversing on a geared-turbine locomotive in the '20s, and I presume this was worked with a positive linkage either way... something specifically eliminated from the booster and I think from the auxiliary locomotives.

For more info:http://users.fini.net/~bersano/english-anglais/locomotive_booster/locomotive_booster.pdf

I did not realize Claude Bersano's site continued to be 'up' this long after his death. If the 'rest' of the material on the site is still up -- it was one of the better references for 'modern' steam. I'm glad to see it has survived!

He and Thierry Stora were two of the great sources.