Centrifugal rotary internal combustion engine

Centrifugal rotary internal combustion engine
Detailed description of the invention
Preamble: The centrifugal rotary internal combustion engine, now presented, break off with
the present ideas and existing concepts about internal combustion engines and so we suggest
to the persons who are contacting with that theme which analyse it with open mind, absence
of preconceits and monolithically ideas. Because, in the following text, it will be necessary,
sometimes, establish comparisons between the new centrifugal rotary internal combustion
engine and others existing internal combustion engines we refer the presented engine only
as rotary or rotative engine and the others as conventional engine specifying better if
necessary.
Introduction: The rotative engine performs a rotary movement directly applied to the engine
shaft without any intermediate mechanical devices and it has variable compression rate. The
detailed description of the invention is beginning by the explanation of mechanical
composition followed by the description of thermodynamic functioning. The understanding
of it becomes necessary the use of the five joint figures.
1 – Explanation of mechanical composition: The simplest rotary engine is composed by two
main parts, being the first the rotary part called rotor which performs the rotary movement
and the second is the immobilized part called stator within it rotates the rotor.
FIGURE 1
a – Mechanical composition of rotor: Figure 1 composed by the drawing 1A in perspective
and, in a transversal cut, by the drawing 1B shows the rotor. We see the engine shaft (1) and
the rotary cylinder (2) where are fixed two equal atypical pistons (3) and (4) and so we only
need to describe the piston (3) which have three different outside surfaces plan/curves: the
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frontal surface (5); the posterior surface (6) and, between them, the inflexion surface (7). In
other side of piston there is the inside surface (8) which follows approximately the shape of
outside surfaces. The end of posterior surface is connected to a fulcrum (9) which is fixed to
an interior furrow (10) slashed into the rotative cylinder corps and the two fulcrums are
separated by 180º centre angle. The frontal part of the piston plunge into an adjusted cavity
(11) perforated into the rotary cylinder corps canning execute dumping movements,
plunging more or less into the adjusted cavity, when the piston are turning around of
respective fulcrum. The dumping of piston describes circumference angles since the inferior
mechanical piston beds until a higher position which may be limited by a conjunction of
folds placed in pistons and within the adjusted cavities.
b – Mechanical composition of stator: Figure 2 composed by the drawing 2A in perspective
and, in a transversal cut, by drawing 2B shows the previous rotor represented by the engine
shaft (1), the rotative cylinder (2) and the two pistons (3) and (4) surrounded by the stator
composed by two twin rings (12) and (12) separated by one interspaces with constant
distance (13), along their entire perimeter and adjusted to the pistons width, allowing the
rotation and dumping of the pistons into the interspaces.
FIGURE 2
Rigidly fixed at twin rings periphery there are two geometric forms (14) and (15) which
perform the same role of cylinders into conventional engine but, not being cylinders, they
are called thermodynamic volumes (TV). These TV are hollows and their inside volumes are
limited on top by a plan/curve surface which we name TV roofs (16) and (17), laterally by
two vertical and plain surfaces (18) and at bottom, partially, by the rotary cylinder surface
and by the outside surfaces of the pistons (19) if they are passing locally. The two TV are
forming an interconnected sequence occupying, each one, 180º angle of twin rings periphery
and rigidifying the joining between twin rings itself and between these and the two TV in
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such way that the lateral surfaces, inside of TV, are coplanar of the interspaces lateral
surfaces of twin rings and thus the pistons, are capable to rotate and dumping into the
interspaces and inside the TV. During the rotary movement of rotor, the pistons mainly
impelled by centrifugal force, will tend to lean on and slide its various lines (they are
mutable during the sliding) of outside surfaces on TV roofs. After the leaning on, the pistons
divide the inside volume of TV into three distinct volumes, tight among them, which are: the
firsts are limited by the frontal roof of TV and frontal surface of pistons, they are called as
retention cameras and indicated by the numbers (20) and (21); the seconds are limited by
the posterior roof of TV and posterior surface of pistons, they are indicated by the numbers
(22) and (23) and they are called as draining cameras; finally the thirds (24) are limited by
the interior surface of pistons and rotative cylinder surface and they are called as bellows
cameras. The leaning on of pistons have a triple effect: firstly the frontal surfaces
conjointly with the opening of respective intake valves (25) and (26) suck gases from
outside; secondly the posterior surfaces conjointly with the opening of respective exhaust
valves (27) and (28) push gases to outside; thirdly the dumping movement of interior
surface of pistons compress and decompress the captive air confined inside bellows cameras
and adjusted cavities making it working like springs and helping the action of centrifugal
force impelling the piston to near of roofs of respective TV.
The two TV are not tight among them because there are gases intercommunication channels
between them (29) and (30) which allows the gases circulation. To prevent the double sense
of that, we introduce into each intercommunication channel one intercommunication valve
(31) and (32) which, oscillating turning around its corresponding fulcrums (33) and (34),
may open or shut the intercommunication channels, respectively, when the tendency of
circulation of gases is on pistons movement sense or in inverse sense. To facilitate this
purpose we foresee a deposit of confined air at the end of intercommunication valves which
works like springs (35) and (36) looking for a normal semi-aperture of valves.
2 – The thermodynamic functioning
a- Principle of functioning: When the two pistons are rotating they perform oscillatory
movements searching leaning on and following the shape of TV roofs and, profiting the
effect of sucking and pushing gases, they may perform the thermodynamic strokes and get
thermic energy which is transformed into mechanical energy at the engine shaft.
b- Introduction: The thermodynamic functioning of the rotative engine with two TV can be
explained using the figure 3 which represents six sequential positions of pistons indicated
into drawings 3A, 3B, 3C, 3D, 3E and 3F during one movement of half rotation.
To explain the sequence we use different colours like blue surface representing the
combustible fresh mixture volume, the gray surface representing the burned gas volume and
the red surface the explosion action. The pistons are yellow and orange. The intake valves
has an automatic behaviour characterized by to open or close when, inside the TV, the gas
pressure is smaller or higher than free atmosphere but the exhaust valves behaviour obey to
outside mechanical definitions. At last, the frontal part of each TV has one ignition spark.
Analysing first the figure 3A we see the pistons pressing both intercommunication valves
which are forced to recoil into their mechanical beds and thus the two TV are isolated for
gases circulation which are fresh mixture into up TV with its intake and exhaust valves both
closed and full of burned gases which are, spontaneously, getting out through the opened
exhaust valve into down TV.
Observing now the figure 3B we see both TV being slightly penetrated respectively by the
yellow and orange pistons. Activated by the centrifugal force and by the pressure of
confined air existing into bellow cameras and adjusted cavities, each piston will tend to lean
on at TV roofs to slide on it. To attain that, the pistons must compress the existing gases
inside of TV where they are penetrating.
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FIGURE 3
A
B
C
D
E
F
The orange piston achieves it easily because the inside gases are getting out through the
respective exhaust valves which is open. However the yellow piston found the up TV full of
fresh mixtures and confined because the intake and exhaust valves and the left side
intercommunication valve closed contradicting the progression of it. Thus the yellow piston
is momentarily floating. However the confination of fresh mixture is changing because the
retention camera of the down TV is continuously increasing and the fresh mixture may
escape to there through the right side intercommunication valve which is open.
Observing now the figure 3C we see the yellow piston still continuing the invasion of up
TV more deeply now, and keeping constant the pressure over the fresh mixture which
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continues responding draining through the right side intercommunication valve to the down
TV retention camera profiting the continuous increasing of that. On other hand, the advance
of orange piston sliding on the down TV roof pushes the burned gas still existing into its
draining camera through the exhaust valve to outside.
Looking now to the figure 3D we can see, finally, the yellow piston lean on at up TV roof
closing the retention camera and transforming it into a convenient combustion camera being
that the appropriate moment to inflame the gas mixture (red area) making appear a flash in
respective spark plug beginning the gas expansion like happen into conventional engine.
Thus, the yellow piston receives one motor impulse and responds with an angular
movement strongly supported by the fulcrum and adjusted cavity and making rotate the
rotor. Then, the thermodynamic behaviour inside of up TV configures a
compression/explosion stroke. Beside that, the yellow piston continues to push the
remaining fresh mixture through the right side intercommunication valve to the retention
camera of the down TV and the orange piston is also expelling the burned gas through the
exhaust valve and the thermodynamic behaviour inside of down TV configures an
intake/exhaust stroke.
In figure 3D we see clearly that there is gas compression into the up TV because the sum of
blue areas with the red area is smaller than the initial blue area in drawing 3A.
Observation:
a – The moment of ignition of fresh mixture into combustion camera must be executed as
soon as the leaning on of piston happen because, in that moment, it occurs the isolation of
the fresh mixture into combustion camera relatively to the others fresh mixture volumes. It is
possible object, alleging that the explosions might not be confined being probable that it
may be propagated to the rest of fresh mixture volume prejudicing the functioning of the
engine. There are reasons to contest this conception: the first is based in the fact of
centrifugal force is greater precisely on leaning on position because the distance of the
geometrical centre of piston to the engine geometrical centre is on maximum value; the
second is the creation of a salience in inflexion surfaces to orientate part of the combustion
gas pressure to reinforce the leaning on of the piston. The introducing of appropriate
segments is also important.
Nevertheless if happens, occasionally, the propagation of gases inflammation that
occurrence does not cause any damages to the engine because the effects are just
momentary and are traducing in the forcing of the piston and intercommunication valve to
recoil to its mechanical beds, still causing a motor impulse over the following piston without
any others consequences.
Passing now to the figure 3E we can see the yellow piston, invader of the up TV,
performing the last moments of compression/explosion stroke continuing to be impelled by
the combustion gas and it is nearing to leave the up TV full of burned gases and the orange
piston invader of down TV performing the last moments of the intake/exhaust stroke with
the intake valve, now open, sucking fresh mixture, which was retained and burned within
the explosion camera of up TV, coming from exterior and leaving the down TV full of it.
Observing finally the figure 3F we see that the mechanical situation returns to a similar
initial position but now with a permuted position of pistons and the down TV full of fresh
mixture with its intake and exhaust valves closed, near to be invaded by the yellow piston to
initiate the compression/explosion stroke and the up TV full of burned gas getting out
through the opened exhaust valve, near to be invaded by the orange piston to initiate the
intake/exhaust stroke.
This conjoint of drawings demonstrates that the two TV rotative engine has conditions to
rotate continuously and its motor shaft is receiving two motor impulses by each rotation.
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3 – The issue of the increasing of TV on twin rings periphery
a – Introduction
The rotary engine may work also with 4, 6, 8, ... , 2n TV on twin rings periphery working
continuously with duets of TV. Following we analyse the engines with 4 and 6 TV.
FIGURE 4
A
B
C
D
E
F
b – The 4 TV rotary engine
To analyse this engine we will use the figure 4 which is composed by the sequential
drawings 4A, 4B, 4C, 4D, 4E and 4F showing ¼ of rotation for four pistons. The two TV
duets are: the first is composed by the up TV (full of fresh mixture) in connection with the
right side TV (full of burned gases) and the second is composed by the down TV (full of
fresh mixture) in connection with the left side TV (full of burned gases). When the green and
orange pistons are invading respectively and simultaneously the up and down TV they are
performing the compression/explosion stroke within.
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Simultaneously the yellow and purple pistons are invading respectively the right and left
side TV and are performing the intake/exhaust stroke. The two duets are concluding two
thermodynamic cycles with two explosions into up TV and down TV. On following 1 4
rotation movement of pistons the TV duets changes being the first the right side TV (full of
fresh mixture) in connection with the down TV (full of burned gases) and the left side TV
(full of fresh mixture) in connection with up TV (full of burned gases) producing again two
explosions into right and left side TV, etc.
All the rest of thermodynamic work like the pistons and valves movements are processing
the same way as explained for two TV engine. Then the engine with 4 TV produces two
simultaneous explosions for each ¼ of rotation and 8 motor impulses by rotation.
c – The 6 TV rotary engine
The 6 TV rotary engine has continuously 3 TV duets working together for each
thermodynamic cycle and, considering the up TV in figure 5 as representing the TV1 and
counting in direct sense, the referred duets are: the first is formed by TV1 and TV2, the
second by TV3 and TV4, and the thirdly by TV5 and TV6. Then, by each 1 6 of rotation of
pistons there are 3 simultaneous explosions into TV1, TV3 and TV5 and thus this engine
produces 6 × 3 = 18 motor impulses by each rotation.
FIGURE 5
d – Generalization of the number of explosions by rotation according the number of TV and
energetic comparison with conventional engine.
Generically the number of explosions produced by each rotation ( MI / R ) of one rotative
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engine with a p (number pair) of TV is given by the formula MI / R = p 2 and so, for example,
a rotary engine with 10 TV in periphery produces 50 MI / R .
Then, considering a rotary and a conventional engine, we may establish an energetic
equivalence saying that both engines are energetically equivalents if they have the same
number of cylinders or TV and they burn the same quantity of combustible at its maximum
rotation. Since the rotary engine produces much more explosions by rotation than the
conventional engine (with exception of two TV rotary engine) with same number of
cylinders then we can establish less rotations to the rotary engine and we establish
2,500RPM as maximum for rotary engine and 6,000RPM as maximum for the conventional
engine. Then the rotary engine with 4 TV produces 20,000 explosions and the equivalent
conventional engine produces 12,000 explosions at maximum and to get the energetic
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equivalence is necessary that each combustion in conventional engine burns 1.7 times more
combustible than each TV of rotary engine. On other hand, the 6 TV rotary engines and 6
cylinders conventional engine produces respectively 45,000 and 18,000 explosions at
maximum and so, to get energetic equivalence each explosion in conventional engine must
burn 2.5 times more combustible. Finally, the two TV and the two cylinders engines is
exception because, to get the energetic equivalence each combustion into rotary engine TV
must burn 1.2 times more combustible.
4 – Another comparisons between the rotary and conventional engines
a – Working characteristics comparison
1) – The rotary engine is much lesser rotative but it has a much greater couple than
equivalent conventional engine.
2) – The rotary engine has not piston dead points and it have a much more soft and
equilibrated movement than equivalent conventional engine.
3) – The rotary engine has automatic working valves except exhaust valves which have
exterior commanded working.
4) – The rotary engine is launched by an electric starter like the conventional engine.
b – Constructive characteristics comparison
1) – The rotary engine is much more bulky and light than equivalent conventional engine.
2) – The rotary engine is much easier to mount and dismount than equivalent conventional
engine.
3) – The rotary engine has much lesser attrition points and pieces to lubricate than
equivalent conventional engine.
5 – Eventual disadvantages of rotary engine
The eventual disadvantages of rotary engine might be on power output or noxious gases
emission but this is considered a little probability. However the fact of rotary engine have
technical characteristics completely news and radically different from the conventional
engines including the Wankel rotary engine and others, does not allow risk to make a
prevision about those themes only with a theoretical approach of rotary engine but only
constructing a prototype is possible to get the answers.
The inventor
Manuel da Silva e Sousa Lobo
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