Internal combustion engines with reciprocating pistons (1), connecting
rods (2), crank (3), block (4), and crankshaft (5) suffer parasitic power loss
from drag on parts moving as much as 180 mph in air ambient the crankcase.
Piston displacement flow crosses connecting rod and crank motion, each at
tornado speed. Racing cars at higher speeds may lose as much as 20 hp.
This loss, while proportional to speed cubed, is still present in slower engines.
This drag is also proportional to gas density. It can be reduced by
evacuating the crankcase with on-board vacuum pump, but at the expense of
additional weight and power consumption. Crankcase ventilation is presently
essential to prevent the build up of blow-by gas past the piston rings. Such
can dilute lubricating oil with unburned fuel and water.
To prevent blow-by from entering the crankcase, provide an additional
sealing ring (7), seated in the cylinder wall and bearing on the piston skirt--
the piston being extended as needed. Then reduce the density of the
crankcase gas by reducing the pressure and/or substituting light gas of lower
than air molecular weight ie hydrogen, helium, methane or mixtures thereof.
The purity of this gas is secured by sealing the crankcase from leaks: sight
glass for dip stick, air lock type oil fill and drainage connection. Instead of
crankcase ventilator, a suitable connection is provided whereby the light-gas
may be evacuated, burned or put outdoors, purged with nitrogen, evacuated
and refilled. This may be done using an external vacuum pump.
A check valve (9) is provided in the cylinder wall below the lowest excursion
of the piston rings but above the cylinder ring. This valve is set to one-way pass
blow-by out under about 1 bar pressure vs the 50 to 80+ bar resisted by the
piston rings. The outlet of this valve goes though an oil separator (not shown)
to exhaust blow-by to the engine air inlet. Lubrication is direct or by spray.
To install the cylinder ring, a groove is made in the bottommost part of the
block adjoining the cylinder suitable to hold the cylinder ring. A cylinder extension
(10) providing an extension of the cylinder and a tight covering of the open face
of the groove is attached to the bottom of the block by screw threads, preferable with
interrupted screw threads.
For assembly, the piston is inserted in the cylinder with connecting rod
attached as usual. the cylinder ring and extension are threaded over the
connecting rod and the expanded around the piston. The ring is then seated in
the groove and the extension (10) is screwed into position enclosing the cylinder
As a minor advantage, the cylinder ring provides stability to the piston, resisting
the tipping moment of the inclined connecting rod, to prevent honing the cylinder
into an ellipse in long usage.