Side
af
764
Forrige
Næste
487
OF ENGINEERING FOKMULÆ.
Slide-valve—continued.
S = Stroke of piston.
x = Distance travelled by th© piston before
the steam is cut off.
y = Distance of piston from end of stroke
before exhaust is cut off.
z = Ditto, ditto, before exhaust begins.
L = Steam lap.
I — Lead of valve.
f — Eduction overlap.
T = Travel of slide.
t = Linear advance = L + I.
a = Angle of advance.
b = Angle of eccentric.
c — Angle of crank = a + 90° - b.
d — Angle of eduction overlap.
2t . , 2L . 2/
Sin. a = ; cosin. o = ; cosin, a — •
s
x = - (1 + cosin. c).
q
y — — [1 - cosin. (a + 90° - d)J.
a '
ar = - [1 - cosin. (a + d — 90°)],