David Joy (engineer), Date of Birth, Place of Birth, Date of Death
TweetDavid Joy (engineer)
British engineer (1825–1903)
Date of Birth: 03-Mar-1825
Place of Birth: Leeds, England, United Kingdom
Date of Death: 15-Mar-1903
Profession: railroad engineer
Zodiac Sign: Pisces 
About David Joy (engineer)
- Joy valve gear is a type of steam locomotive valve gear, designed by David Joy (3 March 1825 – 1903), Locomotive and Marine engineer, and patented (no.
- 929) on 8 March 1879.
- The British patent has not been found but the US patent (US252224 of 10 January 1882) has.
- Joy's gear is similar to Hackworth valve gear but has a compensating mechanism which corrects for "the slight inequality in the motion of the valve arising from the arc of the lever".The drawing (right) shows the Joy gear as applied to a London and North Western Railway locomotive.
- The US patent shows several modifications of the gear.
- In figure 6 of the patent, one of the levers has been replaced by a slide.
Read more at Wikipedia