OIL STAND PIPE
partly relieved from crankshaft rotational variations and totally relieved from end-float effects.
Going to the other end of the shaft, we encounter the beautifully neat torsional spring-drive coupling, the pur- pose of which is to relieve the crankshaft from impeller
the throttle is opened of the impellers does as quickly as is the resulting lag engenders
quickly the "fly- not allow them to crankshaft by the a tendency to twist
the the but
Again, when the throttle is rapidly closed
impellers try to similar twisting
overrun the crankshaft, with reversed effect. To relieve the shaft from these
embarrassments a spring drive is and impellers, which absorbs the
embodied between shaft initial shock loading re-
sulting which, shown
from the inertia. The coaxial shaft and sleeve splined together, form the springing member, are in a detail drawing.
STOP PLATE LIMITING TORSIONAL MOVEMENT
SPRING DRIVE GEAR
There is not such a number
the Griffon as is found
of gears at Merlin, the
the rear end of front-end cam-
T h r e e - q u a r t e r r e a r d e t a i l o f t o r s i o n s p r i n g d r i v e c o u p l i n g a t . r e a r e n d o f c r a n k s h a f t .
nevertheless, there is still a goodly number of wheels, bearings and shafts at the back of the Griffon, and to at- tempt to describe these individually would, as well as being tedious,
almost all be traced in the Max Millar drawing and other details ; how- ever, it is worthy of emphasis that the nest- ing of this mass of drives is as compact and neat as the highest order of mechanical de- sign ingenuity can make it.
In the title sub-head- ing of this article are
Underside view of triple-entry throttle with metering Venturis and injector carburettor.
fc* --' *s
carried to It is for
the absolute of logical this reason, almost
i f w doubtedly, that the Griffon carries further the
by,the Merlin as being the high-
est performance engine in exist- ence, for other engines of similar power are larger or, if of the same size, are lower powered. Such a feature, when coupled to
cannot well be
methods—it of lineage
comes only by way
born of painstaking unrivalled experience.
care and It is on
this foundation that Rolls-Royce rests so
the name securely.
The main body of the Griffon is not unlike the later Merlins in that it has a light-alloy pentagonal-section crank-case, the lower half of which is a dry sump housing the oil pressure and scavenge pumps with their niters in a well at the rear end.
and in the
is this which
is nothing about the
REDUCTION GEAR P'NION COVER
SEMI-FLOATING DRIVE -ANULUS
CRANKSHAFT OIL PEED DE-AERATEh
A baffle plate is also embodied in the lower half case to restrict oil surge and prevent excessive breathing under negative G accelerations. Cylinders are floating wet liners fitted in light alloy jacketing blocks, the compressive stress due to the holding-down studs being taken by the jacket. The liners are chromium plated in the bores for about 2^ inches down from the head as an anti-war measure, it being in this area that maximum wear from corrosion and great
temperatures occurs. head of the liner, and,
A flange is incorporated round the with aluminium sealing rings above
and ing the
below, is nipped between the cylinder head and jacket-
Thus all thermal expansion takes place relative to the
and contraction lower end.
This fashion of nipping the liners at the top means that, when tightened down, there is a gap of 0.15 in. between adjacent faces of the cylinder-head block and the jacketing block which, until one knows the reason, looks very queer. To prevent excessive cantilever loading on the joints adjacent to the end studs when at normal running tem- peratures, flat steel plates are interposed at each end of the cylinder bank between head and jacket, these plates transmitting the load as the engine warms up.
CRANKSHAFT OIL SUPPLY TUBE
AIR BLEED HOLE
Three-quarter front view of semi-floating coupling between crankshaft and reduction gear.
Combustion chambers are machined all over and are quite orthodox in shape. Valve seats are shrunk-in inserts and the porting passages are scurfed—very smoothly indeed on the inlet side (as is to be expected), but fairly roughly on the exhaust side. The valves have Brightray seat fac- ings and, whilst the inlet valves have extended guides, the