|Photo from the Joan Hackworth Weir Collection.|
John Wesley Hackworth left Shildon after his father's death in 1850 (he had been Works Manager) Graces's Guide) "was living at Shildon, aged 30 (born at Walbottle), an Engineer, with his wife Ann and their three daughters, and Joseph Salkeld (age 20) an apprentice. Plus a servant."
and moved to Darlington where he set up a factory in Priestgate and began making stationary engines and machinery, patenting a number of his own inventions. However according to the 1851 census (quoted from
Priestgate itself has been substantially redeveloped since then, so I have no idea where John Wesley Hackworth's factory was located in Priestgate. If anybody knowledgeable about Darlington's history has any information or pictorial evidence on this, I would be glad to receive it.
His patents included -
- The High Pressure Horizontal Steam Engine.
- A Hoisting Machine. (1854)
- An apparatus for working Blast Furnaces by forcing air in a continuous current (1857) and regulating the compression of air.
- A Tubular Heating Cistern.
- Hackworth Radial Valve Gear,1859. He took out a patent for a new type of 'dynamic valve gear' for steam engines. This became known as Hackworth Radial Valve Gear, and gave rise to many similar types of radial valve gear, particularly for marine engine use.
Robert Young wrote "After his father's death, John Wesley Hackworth moved to Darlington where he took premises in Priestgate and began making Stationary engines and machinery. A successful business was built up, one of his first ventures being patent High Pressure Horizontal Steam Engine, which had many unique features to which we shall presently refer. He obtained a patent in 1854 for a Hoisting Machine, with self activating contrivances for stopping the winding as desired, and 1857, an apparatus for working blast furnaces by forcing in air in a continuous current and regulating the compression of the air. He also patented a Tubular heating Cistern, with the object of heating the feed water of steam engines with the exhaust steam of the engine.This was a of rectangular form with top and bottom cast in, and projecting over the sides. the top and bottom of the cistern were perforated with holes corresponding with each other, into which were inserted a series of copper or other metal tubes, the exhaust steam being discharged over the tubes, while the feed water was pumped through them to the boiler . By this means the feed water reached boiling point before entering the boiler. But a much more important discovery was to come. John Wesley Hackworth had long occupied himself an improvement of the ordinary link motion, by simplification, by obtaining a constant "lead" and by easy reversing. In October 1859, he took out a patent for the Variable Expansion Valve Gear applicable to locomotive, marine and other engines, which he named Dynamic Valve Gear. The chief original feature of this was an arrangement and combination whereby two motions were obtained from one eccentric, crank or radial pin. One motion for working the lead of the slide valve, and the other at right angles to the first, to obtain a variable expansion and reverse motion. The advantages claimed and fully realised were -
a) Combination of the two right angle movement whereby quickness is obtained in opening the valve, immediately succeeded by the partial suspension of motion, caused by the movements neutralising each other. Thus, by the well timed action, increased useful effect is obtained.
b) A greater range of variation in the expansion.
c) A great reduction of machinery.
d) The joints are of a more durable kind, and more easily adjusted.
e) Much less power is required for performing the various manipulations.
f) It is much nearer mathematical accuracy than the 'link motion'.
Many other modifications and combinations of the mechanism were described in the patent. It became known as The Hackworth Radial Valve Gear, and as Professor Perry says "is the parent of all the radial gears" (The Steam Engine by John Perry D Sc. R.S. Macmillan & Co Ltd 1889 p143.). It had a host of imitators, but those which followed were mere variations of the original. Some twenty of them are, or were in existence, and they have been applied to almost every description of steam engine.
John Wesley Hackworth's Patent Winch
Winding Engine for the Shildon Coal Company - Designed and erected by John Wesley Hackworth.