1851 Great Exhibition: Official Catalogue: Class V.: Simpson and Skipton
14. SIMPSON and SHIPTON, Trafford Street, Manchester.
Improved short-stroke reciprocating high-pressure steam-engine, driving Parr, Curtis, and Madely's cotton machinery in the Exhibition.
The advantages claimed for this invention are as follow:— The piston, receiving a reciprocative action from the steam, by reason of its mechanical arrangement, gives out a revolving motion, thus reducing the impetus at each return stroke; and from the fact of its containing the properties of the piston and crank combined, it is not subject to the same straining of parts. Although the piston of the ordinary engine at all times receives the full effective pressure of the steam (when the valve is open), there are positions of the stroke when this is useless, as when the crank is "on the centre," consequently the shock is sustained on the several cottars and parts, which is much felt in overloaded engines; but by the arrangements submitted, the crank shaft, which is the piston shaft, receives this shock, which is somewhat diminished on account of the piston itself gliding gradually out of equilibrium into full effect (the same as the common crank, though divested of the intermediate parts).
An advantage is also obtained by working a short stroke with a large effective area of piston, and, consequently, a great speed, with slow velocity of the piston through space, is obtained, compared with the ordinary engine, — thus the first motion can be attached direct to the main shaft, thereby not only dispensing with all intervention of wheel-work, and its necessary appendages, but also producing a steadier motion, consequent upon the engine not having multiplying gear, which must only increase any inequalities in the stroke. This arrangement of engine requires but slight foundations, compared with others, from the peculiar manner in which the power and resistance are compounded together, and from the fact of the capability of these engines to run at high speed, a large power can be concentrated into a small space; hence if such results be obtained, and the multiplying gear be dispensed with, and the number and weight of the parts be reduced, not only economy in first cost will be gained from its close approximation to the ordinary reciprocating engine, but also economy in fuel.