A flight of fancy ?

I came across this and was intrigued by two cylinders driving the one wheel.

Do you think it was made or just a flight of fancy on the designers part.

This looks to me like an example of the principle 'Just because you can doesn't mean you should'.

One major difficulty is the outside crank being so far overhung - a better version might have the cranks between the wheels, but why not just increase the size of one cylinder and don't bother with the other one?

Not that I know much about steam locomotives ...

Cheers, Tim

I think it's an attempt to improve balancing, the 2 cylinders being 180 degrees apart would be in primary balance, apart from a slight rocking couple due to them being slightly ofset. However, as Tim says, the overhung crank looks like a recioe for disaster. I wonder if it was ever made?

I have found out that this locomotive was designed by John Haswell of the Austrian State Railway Works at Vienna and built in 1861 and worked till 1900. It had a top speed of 60 KPH and run without swinging.

Eric,

Probably a design intended to improve the power and smoothness of a locomotive by providing 4 cylinders without having to resort to a crank axel. Back in the days before metallurgy was fully understood and inspection techniques such as X-rays existed, crank axels frequently failed in a catastrophic way resulting in serious accidents. Robert Stephenson used double framing on his Planet type locos that had crank axels thus providing 4 bearings to each axel. If the crank axel fractured each half of the axel would still be supported by two bearings so the loco would safely remain upright on the track.

Beautiful drawing with toned shading, worth every penny. I have a book called The Art of the Engineer full of splendid drawings, my favourite being the oscillating twin cylinder steam engine from Brunel’s Great Eastern shaded with water colour, a true work of art.

Mike