The invention relates to a dynamic imbalanced force generator comprising at
5 least one pair of eccentric mass imbalances and an actuator comprising such a
generator.
A dynamic imbalanced force generator comprising a pair of eccentric mass
imbalances is known from document FR 2 169 672 (01).
Also known is a dynamic imbalanced force generator comprising two pairs of
1 0 ecccnt1 ic mass imbalances to reduce or even eliminate a vibration generated by a
moving body. In this case, the dynamic imbalanced force generator makes it possible
to form a variable dynamic imbalanced force generator, also called an actuator. In
each pair of imbalances, the two masses of the respective pair rotate in a counterrotate
manner. Implementing two pairs of imbalances then makes it possible to
15 control the amplitude of the delivered dynamic imbalanced force by controlling the
phase shift between the two pairs. It is the control of this amplitude, in itself variable,
which makes it a real actuator.
An actuator (variable dynamic imbalanced force generator) of this type is
described in document US 5,903,077 (02) in which the eccentric masses are
20 mechanically coupled in pairs. Position sensors are used to achieve the frequency
and phase control of these masses. The force generated by the eccentric masses is
transmitted via a crankcase supporting the imbalances, which requires that this
crankcase has a mass sufficiently large to be sufficiently robust and stiff to be able to
transmit the dynamic imbalanced force, and not generate parasitic vibratory modes.
25 Moreover, the mechanical coupling of the counter-rotating eccentric mass
imbalances is obtained by external meshing of the two imbalances with parallel axes
by means of toothed wheels with a diameter greater than the outside diameter of the
imbalances. The volume of the actuator is then greater than the volume of the
imbalances themselves, while a large mass not participating in the imbalance effect
30 (the outer toothed ring gear is necessarily balanced and therefore generates no
dynamic imbalanced force). Finally, pairs of counter-rotating imbalances are
preferably placed one around the other, possibly leading to the introduction of a
parasitic vibratory torque into the structure, a torque the amplitude of which is
2
inversely proportional to that of the force generated by the actuator. The actuator
thus constituted has a large and non-versatile size.
Another actuator (variable dynamic imbalanced force generator) of this type
is described in document EP 2 024 660 (03). In this document 03, the four eccentric
5 mass imbalances are mechanically independent. This mechanical independence
gives freedom in the arrangement of the various imbalances. In particular, in order to
reduce the size, the various eccentric masses may be arranged coaxially and side by
side. The control of the various imbalances may then be carried out by electronic
coupling in order to rotate the imbalances in the desired direction. However, as
10 illustrated in Fig. 19a, this coaxial side-by-side position generates a parasitic torque
Mp that is linked to the existence of a non-zero distance along the common axis
between the points of application of the forces F1 (the first imbalance of a pair when
it rotates) and F2 (the second imbalance of this same pair when it rotates).
Yet another actuator (generator of variable dynamic imbalanced forces) of
Hils type is proposed in document EP 0 409 462 (04). Here, the four imbalances are
also mechanically independent. In order to prevent a parasitic torque from being
generated, the imbalances are nested, i.e. the different centers of gravity of each
imbalance lie in the same plane, which, in this case, is perpendicular to the coaxial
axis of rotation of the various imbalances. On the other hand, its overall size is
20 generally greater than that which is implied by the coaxial and side-by-side
arrangement of the various imbalances of document 03. In fact, the overall size is
affected by the radial size associated with this nesting and also by the integration of
the motors dedicated to each imbalance and located between two imbalances.
The present invention aims to solve at least one of the aforementioned
25 disadvantages.
30
More particularly, the object of the present invention is a dynamic
irnbalanced force generator of the type comprising at least one pair of eccentric
masses, which has reduced size and weight, and provides comparable effectiveness
compared to known solutions.
To this end, the invention proposes a dynamic imbalanced force generator
with imbalances, characterized in that it comprises a shaft frame constructed with a
longitudinal axis and further comprising, inter alia:
• at least one support plate of a motor arranged radially with respect to the
longitudinal axis of the shaft frame; and
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• a gear system,
wherein the shaft frame carries:
• a first imbalance constituted by an eccentric mass with respect to the shaft
frame and rotatably connected to the shaft frame through two arms, one of
which is fixed to the gear system;
• a second imbalance constituted by an eccentric mass with respect to the
shaft frame rotatably connected to the shaft frame by an arm fixed to the
gear system, wherein the second imbalance is arranged between the first
imbalance and the shaft frame in a coaxial manner with respect to the first
imbalance;
• at least one motor supported by the support plate and linked with at least
one of the first and second imbalances by means of the gear system,
wherein the support plate and the motor are arranged between the
imbalances and the shaft frame, and between an arm of the first
imbalance and the arm of the second imbalance.
This dynamic imbalanced force generator may comprise at least one of the
following characteristics, taken alone or in combination:
o the shaft frame comprises at least two support plates of a motor
arranged radially with respect to the longitudinal axis of the shaft frame
and as many motors as there are support plates, wherein each is
supported by a support plate and each engages with one of the first and
second imbalances via the gear system, wherein at least one first motor
engages with one of the first or second imbalances, and at least one
second motor engages the other of the first or second imbalances;
o the shaft frame comprises two support plates for a motor arranged
radially with respect to the longitudinal axis of the shaft frame, wherein
each of the first and second motors is supported by a support plate and
each is engaged with only one of the first and second imbalances via the
gear system; wherein the generator further comprises a control unit
adapted to control a counter-rotating rotation of the first and second
motors electronically;
o the gear system comprises two reduction gears each comprising two
toothed wheels of different diameters, one of larger diameter and one of
smaller diameter, wherein each toothed wheel of larger diameter is fixed
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to a different imbalance and engaged with a toothed wheel of smaller
diameter, and wherein each toothed wheel of smaller diameter is frxed to
one end of a drive shaft of a different motor;
o each toothed wheel of smaller diameter comprises an externally toothed
wheel fixed to one end of a drive shaft of a different motor, while the
larger diameter toothed wheels of two reduction gears comprise two
wheels with external toothing, two internal ring gears, or an externallytoothed
wheel, and a crown with internal toothing;
o one of the support arms of the first imbalance is fixed to a first toothed
wheel of larger diameter, while the other support arm of the first
imbalance is fixed to a collar rotatably mounted on the shaft frame via a
bearing, wherein the support arm of the second imbalance is fixed to a
second toothed wheel of larger diameter;
o the motor comprises a through shaft each end of which engages with
one of the first and second imbalances by means of the gear system,
wherein the gear system comprises two reduction gears each consisting
of two toothed wheels of different diameters, wherein the toothed wheels
of smaller diameter are each fixed to one end of the motor shaft and
wherein each engages with one of the two toothed wheels of larger
diameter, wherein the latter are also respectively engaged with a
different imbalance;
o one of the support arms of the first imbalance is fixed to a first toothed
wheel of larger diameter, while the other support arm of the first
imbalance is fixed to a collar rotatably mounted on the shaft, wherein a
bearing and the support arm of the second imbalance is fixed to a
second gear of larger diameter;
o toothed wheels of smaller diameter of the reduction gears consist of
externally-toothed wheels, while the larger diameter toothed wheels
consist of an outer toothed wheel and an inner toothed ring gear;
o one of the support arms of the first imbalance is fixed to the outer toothed
wheel, while the other support arm of the first imbalance is fixed to a
collar rotatably mounted on the shaft frame via a bearing, and wherein
the support arm of the second imbalance is fixed to the inner toothed ring
gear;
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o one of the support arms of the first imbalance is fixed to the inner toothed
ring gear, while the other support arm of the first imbalance is fixed to a
collar rotatably mounted on the shaft frame via a bearing, and wherein
the support arm of the second imbalance is fixed to the outer toothed
wheel;
o the shaft frame comprises a first support arm of a first bearing, known as
the first support arm, arranged radially with respect to the longitudinal
axis of the shaft frame, wherein a mechanical coupling shaft is rotatably
supported by the first arm for coupling the gear system in such a way
that the first and second imbalances are counter-rotating in use;
o the motor has a shaft end engaged with one of the first and second
imbalances via the gear system, wherein the gear system comprises:
• a first reduction gear consisting of two toothed wheels of different
diameters, wherein the toothed wheel of smaller diameter is fixed, on the
one hand, to the end of the shaft of the motor and, on the other hand,
meshes with the toothed wheel with a larger diameter, wherein the latter
is fixed to the first or the second imbalance;
• a second reduction gear consisting of two toothed wheels of different
diameters, wherein the toothed wheel of larger diameter is fixed to the
other imbalance,
a first end of the coupling axle is fixed to the smaller diameter toothed
wheel of the second reduction gear which meshes with the larger
diameter toothed wheel of the second reduction gear, a second end of
the coupling axle is attached to a toothed wheel meshed with the larger
diameter toothed wheel of the first reduction gear so that the imbalances
are mechanically coupled and mounted counter-rotatably relative to one
another;
o the shaft frame comprises at least three support plates of a motor
arranged radially with respect to the longitudinal axis of the shaft frame
and there are as many motors as support plates, wherein each is
supported by a support plate and wherein each engages with one of the
first and second imbalances via the gear system, wherein at least a first
and a second motor are engaged with one of the first or second
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imbalances, and wherein at least one third motor is engaged with the
other of the first or second imbalances;
o wherein the gear system comprises:
• a first and a second reduction gear each consist of two toothed wheels
of different diameters, wherein the toothed wheels of smaller diameter
are fixed, on the one hand, to the end of the shaft of the first and second
motors and, on the other hand, mesh with the larger diameter toothed
wheels, wherein the latter are fixed to the first or the second imbalance;
• a third reduction gear consisting of two toothed wheels of different
diameters, wherein the toothed wheel of smaller diameter is fixed, on the
one hand, to the end of the shaft of the third motor and, on the other
hand, meshes with the toothed wheel of larger diameter, wherein the
latter is fixed to the other imbalance,
• a fourth and a fifth reduction gear, each consisting of two toothed
wheels of different diameters,
wherein a first end of the coupling axle engages v1a the fourth
reduction gear with one of the first and second imbalances,
wherein a second end of the coupling axle engages with the other
of the first and second imbalances via the fifth reduction gear, so that the
imbalances are mechanically coupled and counter-rotatably mounted with
respect to the other;
o the shaft frame further comprises a second support arm of a second
bearing, referred to as a second support arm, arranged radially with
respect to the longitudinal axis of the shaft frame in such a way that the
first and the second bearing are coaxially aligned and the mechanical
coupling axle is rotatably supported by the two bearings;
o the toothed wheels of smaller diameters of the reduction gear consist of
externally-toothed wheels, while the larger diameter toothed wheels
consist of an outer toothed wheel and an inner toothed wheel;
o one of the support arms of the first imbalance is fixed to the outer toothed
wheel, while the other support arm of the first imbalance is fixed to a
collar rotatably mounted on the shaft frame via a bearing, and the
support arm of the second imbalance is fixed to the inner toothed ring
gear;
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o one of the support arms of the first imbalance is fixed to the inner toothed
ring, while the other support arm of the first imbalance is fixed to a collar
rotatably mounted on the shaft frame via a bearing, and the support arm
of the second imbalance is fixed to the outer toothed wheel;
o an electrical supply circuit for the at least one motor extends partly inside
the shaft frame, while the other part extends from the shaft frame through
at least one transverse opening to the motor(s).
iViore precisely, the present invention aims to provide a dynamic imbalanced
force generator having, in addition, an increased stiffness, and which allows versatile
10 use, i.e. it may be coupled vertically or horizontally to a second generator of
imbalanced dynamic imbalanced forces according to the invention, in order, finally, to
form a variable dynamic imbalanced force generator, namely an actuator.
This is why the invention also proposes an actuator comprising two
generators according to the invention, wherein the generators are arranged in the
15 operational position next to one another, while the two shaft frames are parallel to
one another and are coupled electronically.
This is why the invention also proposes an actuator comprising two
generators according to the invention, wherein the generators are arranged in an
operational position, one above the other, while the two shaft frames are parallel to
20 one another and coupled mechanically.
The invention may find an application for counteracting vibrations in various
fields, including rotary-wing aircraft (helicopters in particular) and machines designed
for making paper or concrete blocks and, more generally, machine tools.
Other features of the invention will emerge from the following detailed
25 description made with reference to the accompanying drawings:
30
- Fig. 1 shows a schematic sectional view of a dynamic imbalanced
force generator according to the invention comprising a pair of
eccentric mass imbalances and a single drive motor for the two
imbalances;
Fig. 2 shows a schematic cross-sectional view of a dynamic
imbalanced force generator according to the invention comprising a
pair of imbalances and a single driving motor for one of the two
imbalances, wherein the second imbalance engages in a counter5
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rotating manner with the first imbalance via a mechanical coupling
axle;
- Fig. 3 shows a schematic sectional view of a dynamic imbalanced
force generator according to the invention comprising a pair of
imbalances and a drive motor dedicated to each imbalance;
- Fig. 4 shows a schematic cross-sectional view of a dynamic
imbalanced force generator according to the invention, comprising a
pair of imbalances, two drive motors for a first imbalance, a drive
motor for the second imbalance and an axle for mechanical coupling
of the two imbalances;
Fig. 5 shows a schematic cross-sectional v1ew of a dynamic
imbalanced force generator according to the invention comprising two
imbalance pairs, corresponding more precisely to the association of
two dynamic imbalanced force generators as shown in Fig. 1;
- Fig. 6 to 15 show schematic views in perspective of an exemplary
embodiment of a dynamic imbalanced force generator according to
the invention comprising a pair of imbalances, a motor for each
imbalance and a mechanical coupling axle for the two imbalances;
- Fig. 16 to 18 show schematic views in perspective of an actuator or
generator of variable dynamic imbalanced forces according to the
invention associating two pairs of imbalances, wherein a motor is
provided for each imbalance, as well as a mechanical coupling axle of
the two imbalances of the same pair, according to the diagrams of
Fig. 6 to 15;
Fig. 19a and 19b, show schematic perspective views comparing a
dynamic imbalanced force generator according to the prior art, and a
dynamic imbalanced force generator according to the invention;
- Fig. 20 shows a schematic perspective view of an actuator or
generator of variable dynamic imbalanced forces according to the
prior art as a reference;
Fig. 21a and 21b show schematic views in perspective of two
possible arrangements of an actuator or generator of variable
dynamic imbalanced forces according to the prior art;
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- Fig. 22a and 22b show schematic views in perspective of an actuator
or generator of variable dynamic imbalanced forces according to the
invention and according to two possible arrangements; and
- Fig. 23 shows a graph showing the evolution of the amplitude of the
dynamic imbalanced force (ratio of the force to mass of an actuator
according to the invention with respect to the value of the force to
mass ratio of a reference actuator) as a function of the mass value of
the imbalances of the actuators according to the invention (angle of
the masses), for various possible geometries.
10 According to the invention, the dynamic imbalanced force generator 1
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illustrated in Fig. 1 to 5 comprises a shaft frame 10 with a longitudinal axis X-X'. It
also comprises,
• one or more support plates 11, 12, 13 of a motor M1, M2, M3 arranged
transversely to the longitudinal axis of the shaft frame; and
·a gear system 20, 21 described in detail hereinafter.
The shaft frame 10 also carries:
• a first imbalance 81 consisting of a mass 200 that is eccentric with respect
to the shaft frame 10 and rotatably connected to the shaft frame by two
arms 201, 202, of which one arm 201 is fixed to the gear system 20, while
the other 202 is fixed to a ring 130 mounted rotatably on a bearing 105
fixed to the shaft frame 10 by means of a bearing 130;
• a second imbalance 82 consisting of a mass 300 that is eccentric with
respect to the shaft frame 10 and connected rotatably to the shaft frame
by an arm 301, wherein this arm 301 is moreover fixed to the gear system
21.
The second imbalance 82 is arranged between the first imbalance 81 and
the shaft frame 10, coaxially with respect to the first imbalance 81.
The one or more plates (11, 12, 13) support one (Fig. 1, 2 and 5) or more
(Fig. 3 and 4) motors in engagement with at least one of the first and second
30 imbalances via the gear system 20, 21.
The support plate(s) and the motor(s) are arranged between the imbalances
81-82 and the shaft frame 10, and between the arm 201 of the first imbalance 81
and an arm of the second imbalance 82.
10
This arrangement makes it possible to limit the size of the dynamic
imbalanced force generator.
The gear system 20, 21 makes it possible to connect a motor to the arms
201, 301. The gear system comprises at least two reduction gears 2a and 21 (at
5 least one per imbalance),wherein each comprises two toothed wheels of different
diameters, one toothed wheel of a larger diameter being fixed to a different
imbalance and meshing with a smaller diameter toothed wheel.
10
In a first variant, each toothed wheel of smaller diameter is fixed to one end
of a drive shaft of a motor (Fig. 1, 3 and 4).
In a second variant, a first toothed wheel of smaller diameter is fixed to a
drive shaft of a motor, and a toothed wheel of smaller diameter is fixed to one end of
the rotary coupling shaft (Fig. 2).
The gear system may further comprise at least one additional reduction gear
comprising two toothed wheels of different diameters, one of larger diameter and one
15 of smaller diameter, wherein the toothed wheel of larger diameter is fixed to one of
the imbalances. This toothed wheel of larger diameter may be either separate from
the larger diameter toothed wheel of the other reduction gear engaged with the
imbalance, or it may mesh with this toothed wheel. In the latter case, the two
reduction gears together have only three toothed wheels: a common toothed wheel
20 with a larger diameter fixed to the imbalance concerned, and two smaller diameter
toothed wheels, at least one of which is fixed to a drive shaft of a motor, while the
other may be fixed to one end of the rotary coupling shaft (Fig. 4).
In a particular embodiment of the invention, the shaft frame further
comprises at least one first support arm of a first bearing, called a "bearing arm" 40
25 arranged radially (transversely) with respect to the axis longitudinal X-X' of the shaft
frame 10.
Unlike the generator of document EP 0 409 462, the nested imbalanced
pairs according to the invention are advantageously dissociated and positioned one
on top of the other (Fig. 22a: the position allowing the mechanical coupling and the
30 driving of the two imbalances by a single motor), or next to each other.
This gives the invention a greater implementation flexibility making it
possible to respond all the more advantageously to the allocated volumes close to a
section L/1 = 2 (see Fig. 23), whether this section is wider horizontally or vertically,
and without calling into question the mechanical architecture of the dynamic
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imbalanced force generator (only the control needs to be adapted). The architecture
according to the invention makes it possible, in particular, to produce a mechanicallycoupled
actuator with minimum footprint by virtue of the superimposed positioning of
the two nested pairs (see Fig. 5 and 18).
The advantage of the invention lies in the implementation of a motorization
that is reduced in residual volume, further allowing:
• a central fixed axle (the shaft frame 1 0) which may be dimensioned and
used to support all the mechanical stresses, wherein the crankcase is then
merely a physical barrier against the intrusion of dust or other products, or
to prevent an object from being inserted into the generator during
operation, or to contain the imbalance in the event of failure with
mechanical disengagement of the latter;
• simple implementation of an elementary type of reduction stage (with
internal or external meshing and parallel axes), allowing mechanical
coupling and counter rotation;
• optimization of the force/mass ratio for allocated volumes with square or
non-square cross-section, ideally with a ratio L/1 = 2.
In the embodiment of Fig. 1, the motor M1 comprises a through shaft 30,
each end 30a-30b of which engages one of the first and second imbalances 81, 82
20 via the gear system 20, 21 and the arms 201, 301.
The gear system comprises two reduction gears 20, 21 each consisting of
two toothed wheels of different diameters, one of larger diameter 20a, 21a and one of
smaller diameter 20b, 21 b. The two smaller gears 20b, 21 bare each secured to one
end 30a, 30b of the through shaft 30 of the motor M 1, while each meshes with one of
25 the two toothed wheels of larger diameter 20a, 21a. These latter are also respectively
fixed to a different imbalance 81, 82.
In other words, one of the larger diameter gears meshes with the first
imbalance, while the other of the larger diameter gears meshes with the second
imbalance. It should be pointed out that the larger diameter toothed wheel 20a is
30 externally toothed. The counter-rotation of the two imbalances is ensured by the
choice of the same reduction ratio of the reduction gears 20, 21.
According to another embodiment illustrated in Fig. 2, the shaft frame 10
comprises a first support arm of a first bearing, called the "first bearing arm" 40,
arranged radially with respect to the longitudinal axis X-X' of the shaft frame.
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The motor M1 comprises a non-through shaft 31 having an end 31a
meshing with the first imbalance 81 and also meshing with the second imbalance 82
via the gear system 20.
The gear system comprises:
• a mechanical coupling axle 41 rotatably mounted on the first bearing arm
40, wherein this axle 41 is arranged perpendicularly to the plane of
rotation of the imbalances, i.e. parallel to the longitudinal axis X-X' of the
shaft frame and mechanically coupling the first and second imbalances in
a counter-rotating manner; and
• three reduction gears 20, 22, 22' each consisting of two toothed wheels of
different diameters:
o a first reduction gear 20 coupling the shaft 31 of the motor M1 with one of
the first or second imbalances (in Fig. 2, this is the first imbalance 81);
o two other reduction gears 22, 22' coupling the mechanical coupling axle
41 with the other of the first or second imbalances (in Fig. 2, this is the
second imbalance 82).
More particularly, the motor M1 supported by the support plate 11 meshes
with the first and second imbalances 81, 82 via the gear system. In this embodiment,
the motor is engaged with the first imbalance via the reduction gear 20 and is
20 engaged with the second imbalance 82 via the first imbalance 81, i.e. the second
imbalance 82 is rotationally driven by mechanical coupling with the first imbalance,
itself being driven by the motor (the engagement of the second imbalance with the
motor may be described as indirect).
To this end, the gear system comprises not only three reduction gears 20,
25 22, 22' but also a rotary axle 41 to couple the two imbalances 81, 82 to each other.
30
More specifically, the gear system comprises:
• a first reduction gear 20 consisting of two toothed wheels of different
diameters, one of larger diameter 20a and one of smaller diameter 20b,
wherein the smaller diameter toothed wheel 20b is fixed, on the one hand,
to the end 31 a of the shaft 31 of the motor M 1 while, on the other hand,
meshing with the larger diameter toothed wheel 20a, wherein the latter is
fixed to the first or the second imbalance (in Fig. 2, this is the first
imbalance 81);
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• a mechanical coupling axle 41 rotatably mounted on the first bearing arm
40,
o a first end 41 a of the coupling axle 41 is meshed, via a second reduction
gear 22' with the larger diameter toothed wheel 20a of the first reduction
gear 20 (fixed to the first imbalance in Fig. 2),
o a second end 41 b of the coupling axle 41 is meshed with the other of the
first and second imbalances (in Fig. 2, this is the second imbalance), via
a third reduction gear 22, so that the imbalances are mechanically
coupled and mounted counter-rotatably relative to one another.
Each reduction gear 22, 22' is made up of two toothed wheels of different
diameters, one of larger diameter 22a, 22'a, and one of smaller diameter 22b, 22'b,
wherein the smaller diameter toothed wheel 22b, 22' is, on the one hand, fixed at one
end 41 b, 41 a to the coupling axle 41, while, on the other hand, meshing with the
larger diameter toothed wheel 22a, 22'a, wherein the toothed wheel 22a is fixed to
15 the other of the first and second imbalances (in Fig. 2, this is the second imbalance),
while the toothed wheel 22'a is fixed to the larger diameter toothed wheel 20a of the
first reduction gear 20. The toothed wheel 22a has inner toothing, while the toothed
wheel 20a of larger diameter, has externally loathing.
The counter-rotation of the first and second imbalances is also ensured by
20 the choice of the same reduction ratio of the reduction gears 20, 22, 22'.
Optionally, the shaft frame 10 further comprises a second support arm of a
second bearing, called the "second bearing arm", arranged radially with respect to
the longitudinal axis of the shaft frame in such a way that the first and second
bearings are aligned coaxially, while the rotatably-mounted axle is supported by the
25 two bearings. This makes it possible to maintain parallelism between the mechanical
coupling axle 41 and the axis X-X' of the shaft frame 10.
In the embodiment of Fig. 3, the shaft frame comprises two motors M1, M2,
one for each imbalance B1, B2.
More precisely, apart from the imbalances identical to those of the previous
30 embodiments, the shaft frame comprises:
• two support plates 11 , 12 to support a motor arranged transversely with
respect to the longitudinal axis of the shaft frame,
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• a first motor M1 and a second motor M2 each supported by a support plate
11, 12 and each engaging with only one of the first and second
imbalances by means of the gear system.
The gear system comprises:
• a first reduction gear 20 consisting of two toothed wheels of different
diameters, one of larger diameter 20a and one of smaller diameter 20b,
wherein the toothed wheel of smaller diameter is fixed, on the one hand, to
the end 31a of the shaft 31 of the first motor M1, while, on the other hand,
meshing with the toothed wheel of larger diameter, wherein the latter is
fixed to the first or the second imbalance (in Fig. 3, this is the first
imbalance);
• a second reduction gear 23 consisting of two toothed wheels of different
diameters, one of larger diameter 23a and one of smaller diameter 23b,
wherein the toothed wheel of smaller diameter is fixed, on the one hand, to
the end 32a of the shaft 32 of the second motor M2, while, on the other
hand, meshing with the toothed wheel of larger diameter, wherein the
latter is fixed to the other imbalance (in Fig. 3, this is the second
imbalance).
The counter-rotation of the imbalances is then managed electronically by
20 sensors, preferably at least one sensor for the angular position of an imbalance for
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each imbalance, and a control unit (not shown). In other words, the imbalances B 1,
82 are electronically coupled when the shaft frame 10 does not have a mechanical
coupling axle. In this configuration, the imbalances are therefore mechanically
independent
Fig. 4 illustrates the possibility of providing multiple motors per imbalance,
wherein the number of motors is defined according to the overall performance
specified for the generator, the available space, and the performances of the motors
in question.
In Fig. 4, apart from the imbalances identical to the previous embodiments,
30 the shaft frame comprises:
• three support plates 11, 12, 13 to support a motor arranged transversely
(radially) with respect to the longitudinal axis of the shaft frame;
• a first bearing arm 40, arranged transversely (i.e. radially) with respect to
the longitudinal axis of the shaft frame;
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• a first motor M1, a second motor M2 and a third motor M3 each supported
by a support plate 11, 12, 13 and each meshing with one of the first and
second imbalances via the gear system. The first motor M1 and the third
motor M3 are in engagement with the first imbalance 81, while the second
motor M2 is in engagement with the second imbalance 82.
Alternatively, it is the second imbalance that may be engaged with two
motors, and the first imbalance with a single motor. Equally alternatively, each
imbalance may be driven by two or more motors, depending on the size of each
motor and the resulting extra weight, wherein the support plates and the motors are
10 arranged between the imbalances and the shaft frame and between an arm of the
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first imbalance and the arm of the second imbalance.
The gear system comprises:
• a first reduction gear 20 consisting of two toothed wheels of different
diameters, one of larger diameter 20a and one of smaller diameter 20b,
wherein the toothed wheel of smaller diameter is fixed, on the one hand, to
the end 31 a of the shaft 31 of the first motor M1, while, on the other hand,
meshing with the toothed wheel of larger diameter, wherein the latter is
fixed to the first or the second imbalance (in Fig. 4, this is the first
imbalance 81 );
• a second reduction gear 23 consisting of two toothed wheels of different
diameters, one of larger diameter 23a and one of smaller diameter 23b,
wherein the toothed wheel of smaller diameter is fixed, on the one hand, to
the end 32a of the shaft 32 of the second motor M2, while, on the other
hand, meshing with the larger diameter toothed wheel, wherein the latter is
fixed to the other imbalance (in Fig. 4, this is the second imbalance 82).
• a third reduction gear 20' consisting of two toothed wheels of different
diameters, one of larger diameter 20'a and one of smaller diameter 20'b,
wherein the toothed wheel of smaller diameter is fixed, on the one hand, to
the end 33a of the shaft 33 of the third motor M3, while, on the other hand,
meshing with the larger diameter toothed wheel, wherein the latter is fixed
to the first or the second imbalance (in Fig. 4, this is the first imbalance
81 ).
5
10
16
• a coupling axle 41 rotatably mounted on the first bearing arm 40 and
mechanically coupling the first and second imbalances in a counterrotating
manner.
In Fig. 4, the following characteristics are illustrated:
o a first end 41 a of the coupling axle 41 is engaged with one of the first and
second imbalances (in Fig. 4, this is the first imbalance), via a fourth
reduction gear 22' to the larger diameter toothed wheel of the third
reduction gear (fixed to the first imbalance in Fig. 4),
o a second end 41 b of the coupling axle 41 is engaged with the other of
the first and second imbalances (in Fig. 4, this is the second imbalance),
via a fifth reduction gear 22, so that the imbalances are mechanically
coupled and mounted counter-rotatably relative to one another.
The third reduction gear 22' consists of two toothed wheels of different
diameters, one of larger diameter 22'a and one of smaller diameter 22'b, wherein the
15 smaller diameter toothed wheel 22'b is, on the one hand, fixed to the first end 41 a of
the coupling axle 41 while, on the other hand, meshing with the larger diameter
toothed wheel 22'a, wherein the latter is fixed to the first or the second imbalance (in
Fig 4, this is the first imbalance B1).
The fourth reduction gear 22 consists of two toothed wheels of different
20 diameters, one with a larger diameter 22a and one with a smaller diameter 22b,
wherein the smaller diameter toothed wheel 22b is fixed, on the one hand, to the
second end 41 b of the coupling axle 41, while, on the other hand, meshing with the
larger diameter gearwheel 22a, wherein the latter is fixed to the first or the second
toothed wheel (in Fig. 4, this is the second imbalance B2).
25 Optionally, the shaft frame 10 further comprises a second support arm of a
second bearing, referred to as the "second bearing arm", arranged transversely (i.e.
radially) with respect to the longitudinal axis X-X' of the shaft frame 10 in such a way
that the first bearing and the second bearing are coaxially aligned, and wherein the
rotatably-mounted shaft is supported by the two bearings, thus ensuring better
30 maintenance of parallelism between the mechanical coupling axle 41 and the
longitudinal axis X-X' of the shaft.
Thanks to the mechanical coupling of the two imbalances by the mechanical
coupling axle, it is possible to provide several drive motors per imbalance, since it is
the coupling axis which determines the synchronization of the imbalances.
17
The particular structure of the dynamic imbalanced force generator
according to the invention allows a vertical coupling (Fig. 5 and 18) or horizontal
coupling (Fig. 16 to 18) with two identical sub-parts to generate the dynamic
imbalanced force generator.
5 In general, the toothed wheels of the reduction gears with smaller diameters
are in the form of wheels with external loathing.
When the two imbalances 81 and 82 are mechanically coupled by a rotary
coupling axle 41, the larger diameter toothed wheels of two reduction gears integral
with different imbalances consist of an external toothed wheel and a ring with internal
10 toothing. This permits counter-rotating drive of the imbalances by the mechanical
coupling axle 41. Moreover, identical reduction ratios make it possible to obtain the
counter-rotation at the same (absolute) rotation speed.
For example, one of the support arms of the first imbalance is attached to
the external toothed wheel, while the other support arm of the first imbalance is fixed
15 to a collar rotatably-mounted on the shaft mounted by means of a bearing. The
support arm of the second imbalance is fixed to the toothed ring gear.
Alternatively, one of the support arms of the first imbalance is attached to
the inner ring gear, while the other support arm of the first imbalance is attached to
the collar. The support arm of the second imbalance is fixed to the external gear.
20 In this way, it is ensured that a mechanical coupling between the two
imbalances (by a motor with a through shaft, Fig. 1-5, or by a coupling axle mounted
rotatably on one or two support arms, Fig. 2 -4) generates a counter-rotation of the
imbalances.
When the imbalances are not mechanically but electronically coupled (Fig.
25 3), the type of larger diameter toothed wheels of two reduction gears integral with
different imbalances is not important: they may consist of two wheels with external
loathing, by two toothed ring gears, or by an externally toothed wheel and a ring gear
with internal toothing. What matters is the direction of rotation imposed by the control
unit on each of the motors, which makes it possible to ensure the desired counter-
30 rotation.
Fig. 6 to 15 illustrate an embodiment of a dynamic imbalanced force
generator according to the invention. This is an example of an embodiment
comprising a mechanical coupling axle between imbalances, in accordance with Fig.
4, but a motor per imbalance according to Fig. 3.
18
in Fig. 6, a shaft frame 100 carries two support plates 101 and 102
respectively intended to support a motor (not shown in Fig. 6). The plates 101 and
102 are arranged transversely with respect to the longitudinal axis X-X' of the shaft
frame 100. The latter also comprises a first support arm 103 of a first bearing 1 03a
5 (see Fig. 8), called the first bearing arm 103 and a second support arm 104 of a
second bearing 1 04a, called the second bearing arm 104. The two bearing arms are
arranged transversely with respect to the longitudinal axis X-X' of the shaft frame
100.
Fig. 7 illustrates various bearings 105 fixed on the shaft frame 100 and
10 intended to be mounted in a rotatable manner with respect to this shaft frame 100,
the parts of which will be fixed to these bearings 105.
As shown in Fig. 8, two motors M1 and M2 are fixed on the plates 101 and
102. Each motor M 1 and M2 comprises a shaft M11 and M21, possibly supported by
a bearing 105 carried by a bearing provided in each support plate 101 and 102. It
15 should be noted that the presence of the bearing 105 here is sometimes not
obligatory, in particular when the internal guiding of the motor (which provides a pair
of bearings) is sufficient to absorb the radial, and sometimes axial, stresses
transmitted by the toothed wheel connected to the motor shaft.
In addition, a mechanical coupling axle 110 of the imbalances is supported
20 by the first bearing arm 103 and the second bearing arm 104 when rotating. To do
this, the mechanical coupling axle 110 is fixed on two bearings 105 positioned inside
the bearings 1 03a and 1 04a of the first and second bearing arms 103 and 104.
In Fig. 9, the mechanical coupling axle 110 has not been shown for the sake
of clarity. In this figure, the shaft frame comprises two reduction gears 120 and 121
25 each consisting of two toothed wheels of different diameters, namely a smaller
diameter toothed wheel 120a and 121a and a larger diameter toothed wheel 120b
and 121 b.
The smaller diameter toothed wheels 120a and 121a are fastened to the
shafts M11 and M21 of the motors M1 and M2. These smaller diameter toothed
30 wheels 120a and 121a are formed by externally toothed wheels, while the larger
diameter toothed wheels 120b and 121 b consist respectively of an outer toothed
wheel 120b and an inner toothed wheel 121 b. Each toothed wheel of smaller
diameter 120a, 121a meshes with a larger diameter toothed wheel 120b and 121b.
19
The mechanical coupling axle 110 comprises at each end an externally
toothed wheel meshed, on the one hand, with the larger diameter toothed wheel
120b of the first reduction gear 120 and, on the other hand, with the larger diameter
toothed wheel 121b of the second reduction gear 121. These two larger diameter
5 toothed wheels 120b and 121b are, respectively, an externally toothed wheel and an
internally toothed wheel, wherein the mechanical coupling axle 110 couples these
two toothed wheels in such a way that they counter-rotate in operation.
Fig. 11 illustrates an inverted view with respect to Fig. 10 to illustrate,
moreover, the presence of a collar 130 mounted to rotate on the shaft frame 1 00 by
1 0 means of a bearing 105.
The toothed wheels of larger diameter 120b and 121b, as well as the collar
130, have means for fixing the imbalances 81 and 82 illustrated in Fig. 12 and 13.
These fixing means are holes 106 for the passage of bolts.
As shown in Fig. 12 and 13, each imbalance consists of a mass fixed to at
15 least one arm intended to be carried on the rotatably-mounted shaft.
In Fig. 12, the imbalance 81 comprises a mass 200 fixed to two arms 201
and 202, wherein each comprises a flange 201a and 202a for fastening to the gear
system. The mass 200 has a convex outer face when in the position of use. It also
has a concave inner face when in the position of use. This shape makes it possible
20 both to minimize the size of the mass 200, as well as to allow the mass 300 of the
imbalance 82 to be housed without friction. The latter comprises, attached to the
mass 300, an arm 301 provided with a flange 301a for fastening to the gear system.
The mass 300 has a convex outer face when in the position of use so that it may
rotate without friction underneath the mass 200 of the imbalance 81.
25 Fig. 14 shows the dynamic imbalanced force generator illustrated in Fig. 6 to
11, and to which the imbalance 82 is fixed. More precisely, the flange 301a of the
arm 301 is fixed to the larger diameter toothed wheel121b of the reduction gear 121
by bolts 107 screwed into the threaded holes 106 in the larger diameter toothed
wheel 121b. In this way the imbalance 82 is rotatably connected to the shaft frame
30 1 00 via the reduction gear 121 so that the mass 300 is eccentric with respect to the
shaft frame.
In Fig. 15, the dynamic imbalanced force generator of Fig. 14 further
comprises the imbalance 81 rotatably fixed to the shaft frame 100.
5
20
More precisely, the support arm 201 is fixed to the larger diameter toothed
wheel 120b of the first reduction gear 120. The other arm 202 of the imbalance 81 is
fixed to the collar 130 that is rotatably mounted on the shaft frame 1 00 via bearing
105.
By virtue of this arrangement, the imbalance 81 is located above the
imbalance 82 in the position of use, and has an eccentric mass with respect to the
shaft frame. Furthermore, all the space between the masses 200 and 300 and the
shaft frame 100 is used to house the motors, the gear system and the bearings.
Moreover, the mechanical coupling axle 110 mechanically links the larger
10 diameter toothed wheels 120b and 121 b so that the imbalances are counter-rotating
in use.
Fig. 16 and 17 illustrate an embodiment of a variable dynamic imbalanced
force generator (actuator) comprising two identical dynamic imbalanced force
generators 1, 1 ', and so associated that their shaft frames are parallel. Each dynamic
15 imbalanced force generator 1, 1' complies with a dynamic imbalanced force
generator that has been described in support of Fig. 6 to 15. Each dynamic
imbalanced force generator 1 , 1' is fixed to a protective housing C through its
respective shaft frame. This protective housing serves for protection against dust,
fluids or any external element which may hinder or damage the generators.
20 Advantageously, the attachment of the actuator to its receiving structure is effected
via each shaft frame 10, so that the mechanical stresses do not pass through the
crankcase C. However, in Fig. 16 and 17, a case is shown in which the actuator may
be fixed on the receiving structure (presence of six holes on the crankcase for a
fixing means), and is, therefore, subjected to mechanical stresses: this is generally
?5 penalizing in terms of weight, because the crankcase must be dimensioned
accordingly.
As may be seen in Fig. 18, a variable dynamic imbalanced force actuator or
generator according to the invention may be arranged horizontally (the dynamic
imbalanced force generators 1, 1' are then arranged side by side, or vertically (the
30 dynamic imbalanced force generators 1, 1' are then arranged one above the other).
In the case where the nested imbalances of the same dynamic imbalanced
force generator 1, 1' are positioned side by side (horizontally), it is preferable that
imbalances of the same pair (i.e. within module 1, or of the module 1 ') are rotated in
the same direction (co-rotation). The imbalances of the dynamic imbalanced force
21
generator 1 are however driven in a counter-rotating direction relative to the direction
of rotation of the imbalances of the module 1'. This mode of operation makes it
possible to avoid the generation of a parasitic torque between the two modules 1, 1'.
Advantageously, the dynamic imbalanced force generators 1, 1' are
5 arranged one above the other (vertically). In this case, imbalances of the same pair
(within the same module 1, 1') may be driven in counter-rotation, without generating a
parasitic torque between the two modules 1, 1'. Consequently, this allows the
mechanical coupling and the driving of the two imbalances by a single motor within
the same pair.
10 This gives the invention a greater implementation flexibility making it
possible to respond all the more advantageously to the allotted volumes close to a
section L/1 = 2 (see Fig. 23, where L is the length and I the width), whether this
section is wider horizontally or vertically, and without calling into question the
mechanical architecture of the dynamic imbalanced force generator (only the control
15 needs to be adapted: electronic or not).
20
By positioning the imbalances in a dynamic imbalanced force generator 1, 1'
given in accordance with the invention, the latter generates no parasitic torque Mr in
contrast to the dynamic imbalanced force generator according to the prior art
illustrated in Fig. 19a (document 03).
Fig. 20 to 22b compare the size of a variable dynamic imbalanced force
generator (actuator) of the prior art (Fig. 20, 21 a and 21 b) with the variable dynamic
imbalanced force generator (actuator) according to the invention (Fig. 22a, Fig. 22b).
Thus, Fig. 20 illustrates a generator of variable dynamic imbalanced force
generator according to the document 02. In this document, a square footprint is
25 obtained, each side of which is twice the diameter of only one of the four imbalances.
The length of this side is denoted "L" in Fig. 20.
Fig. 21 a illustrates a variable dynamic imbalanced force generator according
to document 03. This generator has a rectangular size of length L, and width I = L/2.
Therefore, the overall width is less than that of the variable dynamic imbalanced
30 force generator of Fig. 20. However, this arrangement has a double thickness H with
respect to the variable dynamic imbalanced force generator of Fig. 20 and generates,
in addition, parasitic torque Mr.
22
Fig. 21b illustrates the same variable dynamic imbalanced force generator of
Fig. 21 a, but in a vertical configuration, i.e. the pairs of imbalances are arranged one
above the other. The same comments may be made with reference to Fig. 2a.
Fig. 22a and 22b show the size of a variable dynamic imbalanced force
5 generator (actuator) according to the invention. This space requirement is
rectangular and has a length L, and a width I = L/2. On this plane, the configurations
of Fig. 21a or 21 bare thus joined. However, unlike Fig. 21a and 21b, the thickness is
half less than in the generators of Fig. 21 a and 21 b and joins that of Fig. 20.
Furthermore, contrary to the designs of Fig. 21a and 21b, there is no parasitic torque
10 Mp.
The graph of Fig. 23 illustrates the comparison between a variable dynamic
imbalanced force generator according to the invention and a reference, namely a
variable dynamic imbalanced force generator according to Fig. 20 (actuator
comprising four counter-rotating two-by-two and non-coaxial imbalances). More
15 precisely, this graph represents the evolution of the ratio of the force to mass ratio of
a variable dynamic imbalanced force generator according to the invention and the
value of the force/mass ratio of the reference, as a function of the geometry of the
variable imbalances according the invention. The force taken into account in this ratio
is the maximum amplitude of the dynamic imbalanced force delivered by the variable
20 dynamic imbalanced force generator.
The geometry of the imbalances of the variable dynamic imbalanced force
generator according to the invention is represented by the value of the angle
between the two ends of the mass of an imbalance, and passing through the axis of
rotation of this imbalance. In other words, the more open the angle, the more
25 important is the mass of imbalance, all other things being equal (thickness of mass,
material of mass, etc.).
Since the variable dynamic imbalanced force generator according to the
invention and the reference have different geometries, the calculations have been
carried out in order to optimize the masses as a function of the compared
30 geometries.
Thus, for a rectangular architecture such as L/1 = 2, a mass angle of 75' of
the coaxial imbalances according to the invention makes it possible to obtain an
amplitude of the dynamic imbalanced force that is four times greater with respect to
the reference architecture, with identical imbalance mass.
23
Conversely, in order to obtain an amplitude of the dynamic imbalanced force
equal to that of the reference, the architecture according to the invention uses an
imbalance mass four times lower. Thus, with an equal amplitude, the mass of the
antivibration system is decreased, which is a determining criterion in aeronautics.
5 The mass considered in this graph is that of the imbalances alone.
In this case, it is noted that the architecture according to the invention is of
interest only for values of U1 greater than 1, or 1.1. In fact, for a ratio L/1 equal to 1,
the architecture according to the invention seems unfavorable because if the mass of
imbalances increases (i.e. if the angle increases), the amplitude of the dynamic
10 imbalanced force is lower with an architecture according to the invention compared to
a reference architecture.
However, in reality, the mass of the crankcase is not negligible in this
reasoning. Its contribution in the case of Ul = 1 is also particularly favorable to the
architecture according to the invention since, in the end, the volume of the crankcase
15 is reduced by half (in detail A, it is seen that the dimensions of the crankcase may be
reduced since the nested imbalances take up only half of the space). The advantage
is all the more significant if, as this architecture with a fixed central axis according to
the invention allows, the crankcase is eliminated, or if its mass is negligible. In the
end, the ratio of force to mass will therefore be systematically to the advantage of the
20 architecture according to the invention.
Advantageously, the shaft frame will be tubular, 1.e. it will have an internal
space. Moreover, such a tubular shaft frame is illustrated in the accompanying
figures. By virtue of this, and thanks to the fact that the support structures (plates,
bearings, bearing arms) are carried by the shaft frame, an electrical supply circuit for
25 the motor(s) the other part may extend from the shaft constructed by at least one
transverse opening to the motor(s).
30
According to other characteristics of the invention not shown:
• a variable dynamic imbalanced force generator according to the invention
may by used in an aircraft in order to compensate for vibrations of the
aircraft;
• a dynamic imbalanced force generator is advantageously driven by a
control unit in response to a vibration signal received from sensors placed
in the aircraft in an ad hoc manner.
5
24
Thanks to the dynamic imbalanced force generator according to the
invention, the transmission of the force is no longer necessarily achieved by means
of a crankcase capable of transmitting the dynamic imbalanced force, which thus
lightens the assembly,
The motorization of imbalances via single-gear reduction gears (one with a
larger diameter and one with a smaller diameter), as well as the eccentric
arrangement of the, or each, motor, make the generator much less sensitive to
dynamic disturbances, In fact, the interference torque created on the imbalance, and
fed back to the drive shaft is reduced by a factor which is inversely proportional to the
10 square of the reduction ratio of a reduction gear,
The mechanical coupling of the counter-rotating imbalances is obtained by
an internal engagement in the volume of the two imbalances, which optimizes the
volume and the mass used, In the invention, the motorization is positioned between
the pair of coaxial imbalances, while the axle formed by the shaft frame, which allows
15 mechanical coupling through an external toothed wheel and an internal toothed ring,
or directly through a motor and a dedicated shaft, The associated sprockets and
toothed wheels are of smaller diameter than the functional envelope of the
imbalances, which allows a decrease in weight In addition, the drive combines
mechanical coupling and speed reduction while allowing imbalances to be nested in
20 one another along the same axis, which virtually divides the occupied volume and
eliminates any spurious torque effect
The eccentric arrangement of the integrated motor between two nested
imbalances allows a significant reduction in the "force"/"imbalance mass" ratio and a
division by two of the "force"/"volume" ratio with respect to the imbalances with
25 separate axial or unnested coaxial axes, The deviation of the ratio "force"l"imbalance
mass" may range from 1 to 4 in favor of the invention for the same available volume,
according to the geometry of the space dedicated to the system (see Fig, 23), This
advantage comes from the fact that the coaxial arrangement allows for larger
imbalanced diameters, and that the nesting of the imbalances allows division of the
30 volume by two,
It should also be noted that, in the context of the invention, a dynamic
imbalanced force generator such as that shown in Fig, 1 to 15 (two imbalances)
offers the modularity of creating a variable dynamic imbalanced force generator or
actuator (2 times 2 imbalances, i.e, 4 imbalances), as illustrated in Fig, 16 to 18, by
25
arranging each dynamic imbalanced force generator on either side of a horizontal or
vertical wall (or structure). According to the case, the coupling of the imbalances
within the dynamic imbalanced force generators will be mechanical (vertical case,
Fig. a) or electronic (horizontal case, Fig. b) in order to avoid any parasitic torque.
5 Finally, in stabilized mode (at the target rotation frequency), little energy is
required to maintain the rotation, in contrast to the starting transient (in particular at
low environmental temperature). The variable dynamic imbalanced force generator
according to the invention, when it is equipped with at least two motors and where
the synchronization is mechanical, makes it possible to deactivate a motor and to
10 provide redundancy with this secondary motor in order to compensate for a failure of
the main motor.

CLAIMS
1. Dynamic imbalanced force generator (1)
characterized in that
it comprises a shaft frame (1 0) having a longitudinal axis and having, in
·at least one support plate (11, 12, 13) of a motor (M1, M2, M3) arranged
radially with respect to the longitudinal axis (X-X') of the shaft frame; and
• a gear system (20, 21 ),
wherein the shaft frame (1 0) carries:
• a first imbalance (81) consisting of a mass (200) eccentric with respect to
the shaft frame (1 0) and rotatably connected to the shaft frame formed by
two arms (201, 202) of which one (201) is fixed to the gear system (20,
21);
• a second imbalance (82) consisting of a mass (300) eccentric to the shaft
frame (10) and rotatably connected to the shaft frame by an arm (301)
attached to the gear system (20, 21), wherein the second imbalance (82)
is arranged coaxially with the first imbalance (81) between the first
imbalance (8 1) and the shaft frame (1 O);
• at least one motor (M1, M2, M3) supported by the support plate (11, 12,
13) and engaged with at least one of the first and second imbalances (81,
82) via the gear system (20, 21 ), wherein the support plate and the motor
are arranged between the imbalances (8 1, 82) and the shaft frame (1 0)
and between an arm of the first imbalance and an arm of the second
imbalance.
2. Dynamic imbalanced force generator (1) according to
claim 1, wherein the shaft frame comprises:
• at least two motor support plates (11, 12, 13) arranged radially with respect
to the longitudinal axis (X-X') of the shaft frame (1 0);
• wherein each of the motors (M1, M2, M3) is supported by a support plate
and each of the motors is engaged with one of the first and second
imbalances (81, 82) via the gear system (20, 21), wherein at least one
first motor (M 1) is engaged with one of the first or second imbalances, and
5
10
27
wherein at least one second motor (M2) is engaged with the other of the
first or second imbalances.
3. Dynamic imbalanced force generator (1) according to claim 2, wherein
the shaft frame comprises:
• two motor support plates (11, 12, 13) arranged radially with respect to the
longitudinal axis (X-X') of the shaft frame (1 0),
• wherein a first and second motor (M1, M2, M3) is respectively supported
by a support plate and is engaged with only one of the first and second
imbalances (B1, B2) via the gear system (20, 21);
wherein the generator further comprises a control unit designed to control a
counter-rotation of the first and second motors electronically.
4. Dynamic imbalanced force generator (1) according to claim 3, wherein the
15 gear system (20, 21) comprises two reduction gears (2a, 21) each comprising two
toothed wheels of different diameters, a toothed wheel (20a, 21a) of larger diameter
and a toothed wheel (20b, 21b) of smaller diameter, wherein each larger diameter
toothed wheel is fixed to a different imbalance and meshes with a smaller diameter
toothed wheel, and wherein each smaller diameter toothed wheel is attached to one
20 end of a drive shaft of a different motor.
5. Dynamic imbalance force generator (1) according to claim 4, wherein
each smaller-diameter toothed wheel (20b, 21 b) consists of an externally-toothed
wheel fixed to one end of a drive shaft of a different motor, while the larger diameter
25 toothed wheels of two reduction gears consist of two externally-toothed wheels, two
inner-toothed rings, or an externally-toothed wheel and an internally-toothed ring.
6. Dynamic imbalanced force generator (1) according to claim 3 to 5,
wherein one (201) of the support arms of the first imbalance (B1) is fastened to a
30 larger first toothed wheel, while the other support arm (202) of the first imbalance
(B1) is secured to a collar rotatably-mounted on the shaft frame by means of a
bearing, and the support arm of the second imbalance is fixed to a second toothed
wheel of larger diameter.
28
7. Dynamic imbalanced force generator (1) according to claim 1 or 2,
wherein the motor (M1) comprises a traverse shaft (30), each end (30a, 30b) of
which is engaged with one of the first and second imbalances (B 1, B2) via the gear
system, wherein the gear system comprises two reduction gears each consisting of
5 two toothed wheels of different diameters, wherein the two smaller diameter toothed
wheels (20b, 21b) are respectively fixed to one end of the motor shaft and
respectively mesh with one of the two toothed wheels of larger diameter (20a, 21a),
wherein the latter are also respectively engaged with a different imbalance.
10 8. Dynamic imbalanced force generator (1) according to claim 7, wherein
15
20
one of the support arms of the first imbalance is fixed to a first toothed wheel of larger
diameter, while the other support arm of the first imbalance is fastened to a collar
which is rotatably mounted on the shaft by means of a bearing, and wherein the
support arm of the second imbalance is fixed to a second toothed of larger diameter.
9. Dynamic imbalanced force generator (1) according to one of the claims 7
or 8, wherein the toothed wheels of smaller diameter of the reduction gears consist of
wheels with external toothing, while the toothed wheels of larger diameter consist of
an externally toothed wheel and an internally toothed ring gear.
10. Dynamic imbalanced force generator (1) according to claim 9, wherein
one of the support arms of the first imbalance is fixed to the externally toothed wheel,
while the other support arm of the first imbalance is fixed to a collar mounted
rotatably on the shaft formed by a bearing, while the support arm of the second
25 imbalance is fixed to the internally toothed ring gear.
11. Dynamic imbalanced force generator (1) according to claim 9, wherein
one of the support arms of the first imbalance is fixed to the internally toothed ring
gear, while the other support arm of the first imbalance is fixed to a collar mounted
30 rotatably on the shaft formed by a bearing, and wherein the support arm of the
second imbalance is fixed to the externally toothed wheel.
12. Dynamic imbalanced force generator (1) according to one of the claims 1
or 2, wherein the shaft frame (1 0) comprises a first support arm of a first bearing,
5
10
15
20
25
30
29
wherein the first bearing arm (40) is arranged radially with respect to the longitudinal
axis of the shaft frame, and wherein a mechanical coupling axle (41) is rotatably
supported by the first bearing arm for coupling the gear system so that the first and
the second imbalance counter-rotate in use.
13. Dynamic imbalanced force generator (1) according to claim 12, wherein
the motor has a shaft end engaged with one of the first and second imbalances by
means of the gear system, wherein the gear system comprises:
• a first reduction gear (20) consisting of two toothed wheels of different
diameters, wherein the toothed wheel (20b) of smaller diameter is fixed,
on the one hand, to the end of the motor shaft and, on the other hand,
meshes with the larger-diameter toothed wheel (20a), wherein the latter is
fixed to the first or the second imbalance;
• a second reduction gear (21) consisting of two toothed wheels of different
diameters, wherein the toothed wheel of larger diameter is fixed to the
other imbalance,
o wherein a first end of the coupling axle is fixed to the smaller diameter
toothed wheel of the second reduction gear which meshes with the larger
diameter toothed wheel of the second reduction gear,
o wherein a second end of the coupling axle is fastened to a toothed wheel
meshed with the larger diameter toothed wheel of the first reduction gear,
so that the imbalances are mechanically coupled and mounted counterrotatably
relative to one another.
14. Dynamic imbalanced force generator (1) according to claim 12, wherein
the shaft frame comprises:
• at least three support plates (11, 12, 13) to support a motor arranged
radially with respect to the longitudinal axis of the shaft frame;
• as many motors (M1, M2, M3) as there are support plates, wherein each is
supported by a support plate and each engages with one of the first and
second imbalances via the gear system, wherein at least one first and one
second motor is in engagement with one of the first or second imbalances,
and wherein at least one third motor is in engagement with the other of the
first or second imbalance.
5
10
15
30
15. Dynamic imbalanced force generator (1) according to claim 14, wherein
the gear system comprises:
• a first reduction gear (20) and a second reduction gear (22), respectively
consisting of two toothed wheels of different diameters, wherein the
smaller diameter toothed wheel is fixed, on the one hand, to the end of the
first and second shafts of the motors, while, on the other hand, meshing
with the larger diameter toothed wheels, wherein the latter are fixed to the
first or the second imbalance;
• a third reduction gear (22') consisting of two toothed wheels of different
diameters, wherein the toothed wheel of smaller diameter is fixed, on the
one hand, to the end of the shaft of the third motor, while, on the other
hand, meshing with the toothed wheel of larger diameter, wherein the
latter is fixed to the other imbalance,
• a fourth and a fifth reduction gear, each consisting of two toothed wheels of
different diameters,
o a first end of the coupling axle is meshed with one of the first and
second imbalances via the fourth reduction gear,
o a second end of the coupling axle is engaged via the fifth reduction
gear with the other end of the first and second imbalances, so that the
imbalances are mechanically coupled and mounted counter-rotatably
with respect to one another.
16. Dynamic imbalanced force generator (1) according to claim 12 to 15,
25 wherein the shaft further consists of a second support arm of a second bearing,
wherein the second bearing arm (1 04) is arranged radially with respect to the
longitudinal axis of the shaft frame, so that the first and second bearings are coaxially
aligned and the mechanical coupling axle is rotatably supported by the two bearings.
30 17. Dynamic imbalanced force generator (1) according to any one of claims
12 to 16, wherein the toothed wheels of smaller diameter of the reduction gears
consist of externally toothed wheels and the toothed wheels of larger diameter
consist of an externally toothed wheel and an internally toothed ring gear.
31
18. Dynamic imbalanced force generator (1) according to claim 17, wherein
one of the support arms of the first imbalance is fixed to the externally toothed wheel,
while the other support arm of the first imbalance is fixed to a collar mounted
rotatably on the shaft frame by means of a bearing, and wherein the support arm of
5 the second imbalance is fixed to the internally toothed ring gear.
19. Dynamic imbalanced force generator (1) according to claim 17, wherein
one of the support arms of the first imbalance is fixed to the internally toothed ring
gear, while the other support arm of the first imbalance is fixed to a collar mounted
10 rotatably on the shaft frame by means of a bearing, and wherein the support arm of
the second imbalance is fixed to the externally toothed wheel.
20. Dynamic imbalanced force generator (1) according to any one of claims
1 to 19, wherein an electrical circuit for supplying the at least one motor extends
15 partly inside the shaft frame, while the other part exiting from the shaft frame extends
through at least one transverse opening as far as the motor( s ).
21. Actuator comprising two generators according to any one of the claims 1
to 20, in which the generators (1, 1 ') are arranged in a side-by-side arrangement,
20 wherein the two shaft frames are parallel to one another and electronically coupled.
22. Actuator comprising two generators according to any one of claims 1 to
20, wherein the generators (1, 1 ') are arranged one above the other in the
operational position, wherein the two shaft frames are parallel to one another and
25 mechanically coupled.