Gallery opened: 17 Apr 2008Updated: |   
|
A vibratory steam engine has vane pistons very like those of a rotary engine, but they oscillate back and forth rather than turning steadily. A connecting rod and crank will therefore be required to get rotary motion, with all the disadvantages of reciprocating masses that need balancing. The sealing problems are at least as severe as for the rotary engines.
 | Left: A model vibratory steam locomotive.This is a demonstration model of an 0-4-0 patented by J. Jones, Bristol, England, in 1841. It is said to use the "Cambrian drive system" but is evidently not a replica of the Albion. This model is in the Rahmi M Koc (?) museum in Istanbul, Turkey. How it got there is anybody's guess. |
The Mechanics' Magazine said:
"For locomotive purposes it offers the great advantage of a direct transmission of the steam power from the piston shaft to the crank or axle of the driving wheel, by means of a single rod without couplings, and with a much less angle of connexion than is common with the engines now in use."
Which makes very little sense to me, unless it is a reference to the old fallacy that power was somehow wasted if the connecting rod and crank were not at right angles.
 | Left: A development of the Jones design?
This is the "Albion", an 0-4-2 built by Thwaites Bros of Bradford in 1848, for the South Yorkshire Railway. It is supposed to have run there for some 15 years, which would seem to indicate it was successful, though I do wonder if it might have been converted to a conventional layout during that time.
The transverse cylinder was fitted with "vibrating vane pistons" which oscillated the central shaft. There appears to be conventional Stephenson valvegear just to the left of the central shaft. (arrowed)
|
According to a Mr H Crossley, who appears to have part-owned the intellectual property of the Cambrian system, it "...has, by its invariable performances during the last two years and a half, given the utmost satisfaction." (From Mechanics Magazine Saturday June 1st, 1844)
It is possible, of course, that he was not completely impartial in the matter.
This locomotive was one of those featured in a well-known article "Curiosities of Locomotive Design" which was part of "The Development of the Locomotive Engine", by Angus Sinclair, in Railway and Locomotive Engineering for September-December, 1907.
It seems very likely that this engine was built under the Cambrian patent, but so far this is unconfirmed.
|