The
diagrams of figures 10 and 11 are based
on the above formula where:
a = top dead center of smaller cylinder [3]
b = summit of smaller piston [8]
s = surface of smaller piston [8]
l = length of smaller connecting rod [9]
r = length of smaller crankshaft [5]
A = top dead center of larger cylinder [2]
B = summit of larger piston [6]
S = surface of larger piston [6]
L = length of larger connecting rod [7]
R = length of larger crankshaft [4]
Vm = clearance space [40]
α = angular rotation (0° at top dead center ) ( counterclockwise
)
φ = lead angle of smaller crankshaft [5] with respect to the
larger crankshaft [4].
Example to make the engine functional and
performant according to one of the numerous applications:
The above formula stored in a computer computation
sheet allows generation and selection of the dimensional values
of the different engine members, i.e. the compression ratios between
the displacements of the paired cylinders [2] and [3] and the ratio
between the total volume of these cylinders [2] and [3] and the
clearance space [40]; the computation sheet is defined so that the
values reckoned for the maximum and minimum compression ratios of
the engine coincide with the corresponding degrees of the minimum
and maximum lead angles between the crank of the shortstroke crankshaft
and the crank of the longstroke crankshaft, respectively at the
startoftravel and at the endoftravel of the variably timed transmission.
The diagrams of figures 10 and 11 show examples of variation curves
of the compression ratio and of the volumetric efficiency of the
paired cylinders [2] [3] over 360° of angular rotation of the crank
of the longstroke crankshaft [4].
According to a particular embodiment of the
invention, in the case of a highcapacity power unit, the two crankshafts
[4] and [5] are each mechanically connected to a generator and the
electrical circuits of the two generators are connected in parallel.
The capacity of each generator is defined in function of the actual
output of the corresponding crankshaft at cruise speed of the engine,
so that the variably timed transmission and the corresponding couplings
of the two crankshafts [4] and [5] are limited to torque compensating
loads.
