Note: Descriptions are shown in the official language in which they were submitted.
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ELECTROMECHANICAL ARTIFICIAL HEART
FIELD OF THE INVENTION. In the total and partial replacement of hearts.
STATE OF THE ART. Most artificial hearts use pumps that destroy red blood
cells by
heating, speed, friction, compression or turbulence produced, are unsafe or
short-lived, use many
parts or are complex and bulky. The present invention eliminates or reduces
such drawbacks.
DESCRIPTION OF THE INVENTION
Object of the invention.
Provide simple, useful, safe and long-lasting electromagnetic membrane pumps
for
artificial hearts, which eliminate friction.
Use simple, few-piece, generally single-piece, fin valves or leaflets,
inexpensive, durable,
and safe.
Use energy transfer systems through the abdomen using radio frequency,
electromagnetic
waves, magnetic flux with transformers or electrical conductors.
Use a pump drive system using electromagnets or permanent magnets from the
outside,
the latter moving them mechanically.
Use biocompatible, anticoagulant, resistant, elastic, long-lasting and non-
toxic materials.
In the areas of contact with blood, the pieces can be covered with a layer of
biocompatible
material.
Possibility of manufacturing with 3D printing.
Problem to solve.
The lack of donors and the complexity of the current systems. It is solved
with simple,
practical artificial hearts that are easy to apply and replace.
The electromechanical artificial heart uses two diaphragm or membrane
impelling suction
pumps, and is wherein each pump is made up of a discoidal, lenticular, semi-
lenticular or
spherical or oval cap chamber, whose bases of the same shape carry a
reinforcing plate inside,
and to whose periphery two conduits are joined each with a flexible fin check
valve, the chamber
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has a wall that acts as a base or support and another that carries or acts as
a membrane, the
membrane can carry attached, or inside, a paramagnetic or ferromagnetic plate,
(made of soft
iron or ferrite), or a permanent magnet, can also attract a ferromagnetic core
which is attached
and displaces the plate that acts as a membrane being driven or displaced by a
coil or
electromagnet to which it is applies a sinusoidal electrical current with an
electronic oscillator or
multivibrator, or with an actuator or linear motor, which displaces it,
attracting and repelling it,
applying a reciprocating movement to it that creates a chamber of variable
volume and, together
with the fin valves or leaflets at their ends, the suction lift pump. In a
semi-cycle, the current
applied to the electromagnet separates or displaces the membrane towards the
outside, increases
its volume and sucks the blood from the front area, opening the inlet valve or
valves by said
suction. At the end of this half cycle, the suction ends, the inlet valves are
closed and the
electromagnet approaches or moves the membrane into the duct or chamber,
opening the outlet
valve or valves, reducing the volume and driving the blood towards the
different organs. This is
repeated in both chambers or pumps. At the peripheral edges of the chambers,
several
membranes are used in parallel or a membrane of great thickness relative to
the whole. The
electromagnet can attract and repel the plate when it is a magnet. It can also
attract a nucleus
which displaces the plate that acts as a membrane. The set of conduits and
valves can be called
valvular conduits. The chamber can also be considered cylindrical with little
height relative to
the base and can be formed by two plates in the form of spherical caps. Check
valves can also be
ball type. Optionally, the operation can be carried out with a microprocessor
internal or external
to the rib cage, when it is internal, the energy transfer can be done
wirelessly, with: a) An
electrical transformer that introduces the energy in the form of a variable
magnetic flux from the
primary that is external to the secondary one inside the rib cage, (Fig. 1 and
la), b).
Radiomagnetic waves sent from the outside and captured by an internal
receiver, Fig. 2, and c)
.. With electrical conducting wires or conduits crossing the abdomen and some
external batteries,
Fig. 3.
When the microprocessor is external, two cases can occur: a) That the pumps
have the
coils or electromagnets on the outside and the ferromagnetic plates or
ferrites inside the
abdomen, Fig. 4, b) That the pumps carry on the outside a permanent magnet
movable by means
.. of an electromagnet and the ferromagnetic plates inside the abdomen, Fig.
4a, and c) That the
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pumps are on the outside and the blood is sucked and propelled by some ducts
that cross the
thoracic wall through the abdomen Fig. 5 and 5a. The control panel can be used
when the system
is totally or partially external.
Optionally it can carry a cooling system consisting of a stream of air, or
water in a closed
circuit, with a temperature between 23 and 27 C, which is applied externally
by means of a
sheat in the form of a strip around a wide area of the contour of the abdomen,
zone contiguous to
that of the devices and circuits used by the present invention. A heat
exchanger can also be used
consisting of a container whose liquid captures the heat from the chassis of
the internal electrical
and electronic elements and transfers it through said container to the chest
wall where some
connectors allow the coupling of other external ones to apply the cooling
fluid. You can also
carry the heatsink or heat exchanger permanently outside.
It carries blood pressure sensors. A system of mini or micro accelerometers or
gyroscopes
that detect increases in movement or effort so that the microprocessor
increases the pulse rate or
pressure of the pumps, according to the oxygen needs at all times and a
respiratory rate sensor.
The pressure sensors, in addition to next to the pumps, can be placed outside,
taking it around a
limb. These sensors when they are internal can send a variable or oscillating
alternating signal to
the outside, or three oscillating signals, one when the pressure is low, for
example less than 90
mm of mercury, another if the pressure is normal, between 90 and 120 mm and a
third if it is
high above 120 mm. These signals are captured from the outside and are applied
to the
microprocessor.
All materials must be biocompatible, inert, antitoxic, not react with reactive
materials,
respect the environment, if possible hemophobic, or failing that they can be
covered with a layer
of said material, and for valve tabs, membranes or diaphragms elastic
materials can be used. You
can add another property, such as allowing your 3D printing.
Mainly polymers will be used and especially elastomers: vulcanized natural
rubber
(cispolisoprene), synthetic rubber (polyisoprene), artificial form of natural
rubber, styrene-
butadiene rubber (SBR), nitrile rubber (NBR), polychloroprene rubber
(neoprene) and made of
silicone, polybutadiene and polisobutylene (vinyl polymer). Most widely used
biomedical special
polymers such as fluorinated ones: Teflon, polyamides, elastomers, silicones,
polyesters,
polycarbonates but especially those that are hemocompatible that prevent
coagulation, such as
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PET fibres, polytetrafluoroethylene foams, segmented polyurethanes and porous
silicone.
Reinforcing materials such as graphene, graphene oxide or carbyne can be added
as an element
of the future. Other materials with similar characteristics can be used.
They can also be used in some parts: stainless steels, pyrolytic carbon and
ceramic
materials.
The fins of the valves have a semicircular or semi-oval shape and can be
slightly curved,
they rotate around a peripheral edge by means of a flexible reinforcing steel
strap or band that
can also act as a support. The duct will present a semicircular section in
that valve area. On
whose flat face the fin rests and rotates.
The valve fins can be internally reinforced with steel strips, sheets or
filaments using the
most resistant, durable and biocompatible materials. Thicker fins can be used
which will make
them more durable. Peripheral membranes or diaphragms can also be internally
reinforced with
fibres or fabrics. They must be magnetically isolated with a thin metal
casing. A variant carries a
metal disk or circle in the centre of the membrane, which can be coated with
titanium or any
other incompatible and durable material. The valve like the one in patent
P201700249 can be
used.
Two pumps in series and two vanes in series can be used at the end of each
pump. The
pumps can have strong, insulated and shielded housings.
One or two electromagnets can be used, one on each side of the pump variable
volume
chamber.
Pressure or leakage sensors of the membranes or booster chambers warn, with
acoustic or
visual alarms, of breakage or failure of booster pumps.
The impeller pumps carry out both the delivery and the recovery of the fluid,
they can
also send the fluid and when the impulse ceases, the recovery is carried out
by means of the
elastic walls, which have great consistency and act as springs.
Refrigeration or temperature control is done internally and externally.
Refrigeration is
optional
The control system is very simple, since when the heart is completely
transplanted, the
regulation of the whole, controlling the pressures and the respiratory rhythm,
is done more
easily.
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Advantages: The pumps, membranes and valves are very simple, they do not break
red
blood cells, they allow one-piece assemblies, 3D printing manufacturing,
simple and quick
change using quick disconnect fittings, they do not have internal axes of
rotation in contact with
the blood, nor motors, little energy is needed, the system can be magnetically
shielded, friction
5 .. does not occur, nor high temperature in some cases. Multi-fin valves and
peripheral multi-
membrane pumps can be used, between which breakage leaks can be detected,
anticipating their
change. It is practical, economical and safe. Due to its simplicity and small
size, it allows the
system to be duplicated for protection in the event of failures or emergency.
It solves the lack of
donors. Electromagnets unlike motors can act smoothly with a sine wave
current. The set of
pumps and valves can be considered much simpler than those of the heart. With
two pumps in
series or in parallel, or by adding an accumulator, an almost continuous flow
of blood can be
sent. It is valid for temporary use and also long-term or permanent. They can
be used in several
different ways depending on the patient's problem. It has notice of failures
due to leaks, breaks,
etc. Due to its simplicity, it could be used in very critical patients who are
currently very
dangerous to apply any surgical treatment or even in animals with heart
disease, which otherwise
should be euthanized. Accelerometers or gyroscopes warn of sudden physical
changes in the
patient. The control system is very simple, with a microprocessor which
controls the blood
pressure depending on the conditions or data received at all times. The
cardiovascular system is
the one with the highest number of cases of death, many of them due to lack of
donors.
DESCRIPTION OF THE DRAWINGS
Figure la shows a schematic and cross-section view of a rib cage with the
right
ventricular substitute pump.
Figure lb shows a schematic and sectional view of a rib cage with the left
ventricular
replacement pump.
Figure lc shows a schematic and partially cross-section view of a left
ventricular
surrogate pump.
Figure ld shows a schematic and partially cross-section view of a right
ventricular
surrogate pump.
Figure 2 shows a schematic and cross-section view of a rib cage with the
internal
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microprocessor, which transfers the energy from the network to the interior
with a transformer.
Figure 2a shows a schematic and cross-section view similar to Figure 2, which
adds
circuits that transfer the signals to the interior and exterior of the
abdomen, using a transformer.
Figure 3 shows a schematic and cross-section view of a rib cage with the
internal
microprocessor, which transfers energy to the interior with a radio frequency
transmitter and
receiver.
Figure 3a shows a schematic and cross-section view of a rib cage with the
internal
microprocessor, which transfers energy to the interior by means of a battery
and conductors that
pass through the abdomen.
Figure 4 shows a schematic and cross-section view of a rib cage with the
external
microprocessor, which carries the pumps inside and the electromagnets or coils
outside. Only
one pump is shown.
Figure 4a shows a schematic and cross-section view of a rib cage with the
external
microprocessor, which carries the pumps inside and magnets moved by
electromagnets or
piezoelectric actuators on the outside. Only one pump is shown.
Figures 5 and 5a show schematic and cross-section views of a rib cage with the
external
microprocessor, carried by the pumps on the outside and some conduits that
cross the abdominal
wall. Only one pump is shown in each rib cage.
Figure 6 shows a schematic plan view of a pump or ventricle.
Figure 7 shows a schematic and profile view of a lenticular pump or ventricle.
Figure 7a shows a schematic and partially cross-section view of a slightly
semi-lenticular
artificial ventricle or domed variant.
Figures 8 to 15 show schematized and partially cross-section pumps with the
pipes and
valves on both sides, although in practice they will be positioned taking into
account the
locations of the elements to which they must be connected. But preferably as
in Figures 6, 7, 7a
or 15.
Figure 16 shows a schematic view of a complete heart with its casing and in
profile.
Figure 17 shows a block diagram with one possible way of operation.
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MORE DETAILED DESCRIPTION OF AN EMBODIMENT OF THE INVENTION
Figure 2 shows an embodiment of the invention, with the primary (13t) of a
transformer
external to the rib cage, which supplies its secondary (14t) with alternating
current in the inside
it, with a reduced voltage, which is rectified and transformed into direct
current by the rectifier
(12), charging the battery (80) (this can be replaced by a capacitor) and
feeding the
microprocessor (90), from where they are sent the impulses or sine waves to
actuate the
electromagnets of the pumps (2) (VD) and (3) (VI), substitutes for the right
and left ventricles
respectively. Blood pressure signal (s) (70) and a system of mini or micro
accelerometers or
gyroscopes (71) are applied to the microprocessor that detect increases in
movement or effort, if
you are lying down and the respiratory rhythm (72), to The microprocessor
controls the pulse
frequency of the pumps. Refrigeration may not be necessary as blood
circulation can reduce the
temperature.
Figure la shows the approximate arrangement of the placement of the elements
when
replacing the right ventricle with the pump (2) and the conduits (45) that
join the right ventricle
(2) (VD) with the vena cava (4) and the pulmonary arteries (5).
Figure lb shows the approximate arrangement of the placement of the elements
when
replacing the left ventricle with the pump (3) and the conduits (67) that
connect the left ventricle
(3) (VI) with the pulmonary veins (6) and the aorta (7).
Figure lc shows a pump replacing the left ventricle (3) LV that consists of
the
electromagnet (1), which attracts or repels the ferromagnetic plate (41) in a
circular or oval shape
which has a thin peripheral crown (42) and both are introduced, joined and
integrated in the
circular crown (39) of great relative thickness, whose internal zone deforms
when the plate (41)
is attracted or repelled, varying the central chamber (23), to which the two
fin valves (22) at its
ends. Blood is suctioned from the oxygenated pulmonary veins (6) and sent to
the aorta (7). The
annulus (42) can be replaced by multiple radial fins or strips. Two or more
fins or valves can be
used at each end. Plate 41 is repelled and attracted when it is a permanent
magnet.
Figure ld shows a pump replacing the right ventricle (2) V.D. and the
electromagnets (1),
one on each side, which attract or repel the ferromagnetic plate (41) of
circular or oval shape
which has a thin peripheral crown (42 ) and both are inserted, joined and
integrated in the
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flexible circular crown (39) of great relative thickness, whose internal area
deforms when the
plate (41) is attracted or repelled, varying the central chamber (23) to which
the two contribute
fin valves (22) at their ends. Blood is suctioned from the superior and
inferior vena cava (4) and
sent to the pulmonary arteries (5). The annulus (42) can be replaced by
multiple fins, or radial
strips. Two or more fins can be used at each end. Plate 41 is repelled and
attracted when it is a
permanent magnet.
Figure 2a with the primary (13t) of a transformer external to the rib cage,
which feeds its
secondary (14t) inside it, with a reduced voltage, which rectifies it and
transforms the rectifier
(12) into direct current, charging the battery (80) (this can be a capacitor)
and feeding the
microprocessor (90) from where the impulses or sine waves are sent to actuate
the
electromagnets of the pumps (2) (VD) and (3) (VI), substitutes for the right
and left ventricles
respectively. The microprocessor receives the blood pressure signals (70) and
from a system of
mini or micro accelerometers or gyroscopes (71) that detect increases in
movement or effort, if
you are lying down and the respiratory rhythm (72), so that the microprocessor
controls the pulse
frequency and pressure of the pumps. A system for transmitting and receiving
signals from the
inside to the outside (81, 82 and 83), using the transformer circuit.
Figure 3 shows the external radio frequency transmitter (13r), whose signal is
received
inside the abdomen with the receiver (14r) whose reduced alternating current
is rectified and
transformed into direct current with the rectifier (12), charging the battery
( 80) (this can be a
capacitor) and feeding the microprocessor (90) from where the impulses or sine
waves are sent to
actuate the electromagnets of the pumps (2) (VD) and (3) (VI), substitutes for
the ventricles right
and left respectively. The microprocessor is applied the blood pressure signal
(70) and a system
of mini or micro accelerometers or gyroscopes (71) that detect increases in
movement or effort,
if you are lying down and the respiratory rate (72) so that the microprocessor
controls the pulse
frequency of the pumps. It adds an optional cooling system from the outside,
consisting of a
chamber-duct (50) with its thermally insulated walls, which is attached to an
adapter in the
abdomen that carries two fittings (51) that allow, if necessary, the coupling
a circuit with a
cooling fluid.
Figure 3a shows the external battery (80e), which supplies direct current to
the internal
.. microprocessor (90i) from where the impulses or sine waves are sent to
actuate the pumps (2)
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(VD) and (3) (VI), substitutes of the right and left ventricles respectively.
The microprocessor
receives the blood pressure signal (s) (70) and a system of mini or micro
accelerometers or
gyroscopes (71) that detect increases in movement or effort and the
respiratory rhythm (72) so
that the microprocessor controls the pulse frequency and pump pressure. Figure
4 shows the
external microprocessor (90e) that feeds the electromagnet (2e1) that operates
the armature of the
pump (2ar) that supplies the right ventricle (VD) Blood is sucked from the
superior and inferior
vena cava (4) and sends it to the pulmonary arteries (5). For the left
ventricle, it is similar to that
for the right.
Figure 4a shows the external microprocessor (90e) that feeds the electromagnet
(2e1) that
operates and moves the magnet (2im). This, in turn, displaces the armature of
the pump (2ar)
from the right ventricle (VD). Blood is suctioned from the superior and
inferior vena cava (4)
and sent to the pulmonary arteries (5). For the left ventricle, it is similar
to what has been stated
for the right.
Figure 5 shows the external microprocessor (90e) that feeds the electromagnet
of the
equally external pump (2), which supplies the right ventricle (VD). Said pump
sucks the blood
from the superior and inferior vena cava (4) and sends it to the pulmonary
arteries (5), through
the conduits (45) that cross the abdomen.
Figure 5a shows the external microprocessor (90e) that feeds the electromagnet
of the equally
external pump (3), which supplies the left ventricle (V.I.). This pump sucks
the blood from the
oxygenated pulmonary veins (6) and sends it to the aorta (7), through the
conduits (67) that cross
the abdomen.
Figure 6 shows the lenticular, discoidal or cylindrical camera (41) that
carries the coil (1) on
one side and the ferromagnetic core in the centre. In the periphery it carries
the conduits (39)
with the valves (22).
Figure 7 shows the lenticular camera (41) that carries the coil (1) on one
side and the
ferromagnetic core in the centre. In the periphery it carries the ducts (39).
Figure 8 shows a pump (41a) of the discoidal or cylindrical type, formed by
two circular plates,
the upper (46), which is mobile, and the lower (47), which is fixed,
internally reinforced by a
metal plate (43), non-ferromagnetic. With two conduits (39), each with a fin
valve (22). By
applying current to the coil (1), which is fixed, it displaces the
ferromagnetic core (40) and the
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plate (46). The (m) is used to indicate moving elements. The peripheral edge
is a semi-tubular,
rubber, flexible and elastic that acts as a recovery spring once the current
is extinguished.
Figure 9 shows a pump (41b) of the discoidal or cylindrical type, formed by
two circular
plates, the upper one (47), which is mobile, and the lower one (46) which is
fixed, internally
5
reinforced with a metal plate (43). non-ferromagnetic. With two conduits (39),
each with a fin
valve (22). By applying current to the coil (1), which is fixed, it attracts
the ferromagnetic disc
(48) and the plate (47) that acts as a membrane. The (m) is used to indicate
moving elements.
The peripheral edge is tubular, almost toroidal, made of rubber, flexible and
elastic and acts as a
return spring when the current is extinguished.
10
Figure 10 shows a pump (41c) of the discoidal or cylindrical type, formed by
two circular
plates, the upper (46), which is mobile, and the lower (47), which is fixed,
internally reinforced
by a metal plate (43). non-ferromagnetic. With two conduits (39), each with a
fin valve (22). By
applying current to the coil (1), which is fixed, it displaces the
ferromagnetic core (40) and the
plate (46). The (m) is used to indicate moving elements. The peripheral edge
is tubular, almost
toroidal, made of rubber, flexible and elastic, which acts as a recovery
spring once the current is
extinguished.
Figure 11 shows a pump (41d) of the discoidal or cylindrical type, formed by
two circular
plates, the upper one (46), which is mobile, and the lower (47) which is
fixed, internally
reinforced by a metal plate (43). non-ferromagnetic. With two conduits (39),
each with a fin
valve (22). By applying current to the coil (1), which is mobile, it moves
together with the plate
(46) with respect to the magnetic disk (42). The (m) is used to indicate
moving elements. The
peripheral edge is formed by several concentric toroidal quasi-tubular
elements.
Figure 12 shows a pump (41e) of the discoidal or cylindrical type, formed by
two circular
plates, the upper one (46), which is mobile, and the lower (47) which is
fixed, internally
reinforced by a metal plate (43). non-ferromagnetic. With two conduits (39),
each with a fin
valve (22). By applying current to the coil (1), which is fixed, it displaces
the ferromagnetic core
(40) and the plate (46). The (m) is used to indicate moving elements. The
peripheral edge is
made of elastic rubber, bellows type.
Figure 13 shows a pump (411) made up of two plates in the form of spherical
caps, the
innermost one attached to the stem (61) which is driven by the linear or
piezoelectric actuator or
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motor (60) and the outermost being fixed, internally reinforced by a metal
plate. With two
conduits (39), each with a fin valve (22). By applying current to the
actuators or linear motors
(60), the stem (61) is actuated that actuates the internal plate of the pump.
These transform their
rotary movement into another alternative of the shaft (61). They are housed in
the cavity to take
advantage of the space.
Figure 14 shows a pump (41g) of the discoidal or cylindrical type, formed by
two circular
plates, the upper (46), which is mobile, and the lower (47), which is fixed,
internally reinforced
with a metal plate (43). non-ferromagnetic. The top plate adds a magnetic
plate (44) which is
repelled and both shifted downward when coil (1) is applied to power. With two
conduits (39),
each with a fin valve (22). The (m) is used to indicate moving elements. The
peripheral edge is
semi-oval in section.
Figure 15 shows two pumps or ventricles (41h) attached by their base or fixed
plate (47), a
schematic and partially cross-section view of two type pumps (41g) of the
discoidal or
cylindrical type, formed by two circular plates, the upper one (46), which is
mobile, and the
lower one (47) which is fixed and common to both, internally reinforced by a
non-ferromagnetic
metal plate (43). The top plate adds a magnetic plate (44) which is repelled
and both moved
downward when current is applied to the coil (1). With two conduits (39), each
with a fin valve
(22). The (m) is used to indicate moving elements. The peripheral edge is made
of elastic rubber
and semi-oval section.
Figure 16 shows the casing of the artificial heart (50), with the peripheral
conduits (39)
connectable by means of the quick disassembly fittings for the right ventricle
(38d) and for the
left ventricle (38i). And the electrical connectors, the (51d) for the right
ventricle and the (51i)
for the left.
Figure 17 shows the microprocessor that receives signals from the starter
switch,
accelerometers and gyros that detect sudden changes or excess movement, sensor
of the amount
of oxygen in the blood, detector of cardiac arrest, increase of work, tension
or pressure of the
substitute pumps. of the ventricles, pulsations and faults, it processes them
and sends information
about the state and operation of the machine, fault warning, data of pressure
and pulse of the
patient. Sending the pulsating current to the electromagnets (1) of the pump
(2) that replaces the
right ventricle and the pump (3) of the left ventricle that carry the fin
valves (22) to the inlet and
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outlet and that when pressing alternately the chambers (23), pump the blood to
their respective
arteries and veins.
In the description, lines and valves are shown on both sides of the pumps for
ease of
explanation. However, for each duct, the most suitable peripheral point can be
used to join the
corresponding veins and arteries.
Also the placement of the electromagnet and the ferromagnetic plates with
respect to the
pumps can be carried out in different ways, external, internal and integrated
in the membrane,
and of greater or lesser diameter.
The peripheral edges of all pumps are flexible and elastic: rubber or special
silicones that act
as a recovery spring once the current is extinguished.
In some chambers the elements marked with an (m) are mobile, the others are
fixed or are
fixed to the structure of the pumps.
The metallic mobile elements also other solid ones, allow to be observed from
the outside
by means of ultrasounds or x-rays.
The elements of the different systems can be interchanged with each other, for
example
electromagnets and actuators or linear motors.
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