Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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TITLE OF THE INVENTION
THERAPEUTIC SPIRAL MAGNET
TECHNICAL FIELD TO WHICH THE INVENTION RELATES
The present invention relates generally to spiral magnets. More specifically,
the
present invention relates to devices comprising spiral magnets which are
usefully employed
for therapeutic applications.
BACKGROUND ART
The use of magnetic fields for therapeutic application is well known. For
example,
U.S. Patent No. 4,549,532 issued October 29, 1985, to Baermann disclosed a
flexible
magnetic foil for therapeutic purposes. Primarily, the therapeutic action was
produced by
the Hall effect, which caused a load separation within an electrolyte which
flows through
the magnetic field. Electric voltages were thereby created diagonally to the
flow direction,
which can generate the desired therapeutic action in the sections of the body
thus treated.
Such devices for therapeutic application were typically manufactured using
foils
which were made of a rubber-type flexible plastic, which preferably was skin-
compatible.
Permanently-magnetic particles were embedded in the plastic, and these
permanently-
magnetic particles were preferably permanently-magnetic particles of a ferrite
or rare-earth
component, for example, barium ferrite or strontium ferrite, or NdFeB. These
permanently-magnetic particles were aligned by applying an external magnetic
field to one
side, or to both sides of the foil and thus to create a magnetically-polarized
area. The
conventional foil was thus a sheet-type formation, with a commonly available
foil thickness
of between 0.3 mm and 1.5 mm.
Various designs of such conventional magnetic foils are known. They were made
by
stamping or cutting from commonly-available magnetic foils, normally in the
form of
circular discs or rectangles. Double or mufti-polar magnetization was usually
carried out
laterally on one side. The pole configurations thereby were usually in the
form of straight
lines, concentric circles, spirals, rectangles, or sections, as well as other
geometric
formations. Only in the case of axial magnetization, whereby one surface had a
single N-
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pole and the reverse side of the foil had a single S-pole, were identical
magnetic induction
values shown at corresponding measuring points on both sides.
In contrast to a double sided lateral mufti-polar magnetization, the
aforementioned
single-sided lateral mufti-polar magnetization had the advantage that it was
normally very
practical and showed higher induction values on the side of the foil adjacent
to the body of
the patient than it would exhibit in the case of two-sided lateral
polarization with the
identical pole configuration, irrespective of the configuration.
However, the above dual or mufti-polar lateral magnetizations of such sheet-
type
formations were unfavourable due to the magnetic flux direction being curved
within large
sections of the foil. The desired total saturation polarization of the overall
available
magnetic material, on the utilization side of the foil facing the body, can
thus no longer be
ensured.
This problem proved to be of particular disadvantage for magnetic foils which
were
used for therapeutic purposes, where the pole width was larger than the foil
thickness.
However, magnetizing with pole widths which were in excess of the 1-time,
often even 20-
times, that of the foil thickness were preferred due to their desired greater
dispersion into
deeper areas of the body. An additional disadvantage of this type of
magnetization has
proven to be the leakage flux which formed on the reverse side of the foil,
due to the low
relative permeability of ~ci = 1Ø This may be as much as 75 % of the area of
the foil
facing the body and reduced the desired beneficial flow considerably.
In some cases, however, this disadvantage was compensated by the side of the
foil
facing the body being covered by a magnetic, highly-permeable foil, for
example, of thin,
low-carbon steel sheeting. Due to this magnetic reflux, the utilization flux
of the foil was
highly increased. A disadvantage, however, was the use of steel sheeting
which, due to its
negligible thickness, presented a considerable injury potential. Its use
increased the
manufacturing price and also reduces the flexibility of the foil.
Therefore, in summary, the use of such magnetic therapeutic devices was
limited by
the strength of the polarization. With a weak polarization of the foil used,
the effect
produced by the magnetic field within the body, was also weak.
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DESCRIPTION OF' THE INVENTION
An object of a broad aspect of the present invention is to provide a magnetic;
device
for therapeutic application which may be easily manufactured and which
generates a
strong and effective magnetic he d.
.A first broad aspect of the' present invention provides a magnetic spiral
device for
therapeutic application. Such maL;netic spiral device includes at least one
flexible foil
strip, the foil strip having a length and a width that define a larger side
face, and having
the length and an axial depth that define a smaller side fare that adjacently
faces a body of
a patient. Such foil strip is magn estically polarized in an axial depth
direction prior to
coiling the foil strip into a spiral pattern, and is coiled along its larger
side face. The coil
strip is configured for subsequent therapeutic magnetic effect in a lateral
direction to the
body of the patient.
By a first variant of this first broad aspect of the present invention, the
foil strip has
a right angle cross section and includes a dispersion of powder-type magnetic
components
embedded therein. I3y a first variation thereof, the magnetic components
comprise ;~r-
ferr~ite or NdFeB, having an average particle size smaller than 1. By a second
variation
thereof, the average particle size of the magnetic components is smaller than
100p.
By a second variant of this tirst broad aspect ofthe present invention, the fo
l strip
includes at least two varying magnetic polarizations which are applied to each
larger side
face of the foil strip in opposition to one another.
By a third variant of this first broad aspect of the present invention, the
magnetic
strip includes a plurality of areas with varying polarization serially
alternating with one
another on a side face along the lengthwise extent of the foil strip. By a
variation thereof,
each of the areas has a length which is at least 2 ~c radians when coiled.
By a fourth variant of this first broad aspect of the present invention, the
magnetic
spiral device includes at least two foil strips which are positioned in end-to-
end abutment
and are coiled up collectively, one after the other into a single spiral
configuration, so that
the polarization of the larger side faces of each of the at least two foil
strip changes at the
end-to-end abutment thereof.
By a fifth variant of this first broad aspect of the present invention, the
magnetic
spiral device is in th.e form of a generally-cylindrical configuration and has
a cylinder
height which is less than the dianroter of the cylinder.
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By a sixth variant of this first broad aspect of the present invention, the
therapeutic
device includes at least two magnet spirals as described hereinabove.
By a first variant of this suxth variant of the present invention, the pair of
magnet
spirals are separated from one another by a predetermined separation distance.
By a
second variation thereof, the pair of magnet spirals are substantially
parallel to one
another.
By a seventh variant of this first broad aspect of the present invention, at
least one
foil strip is coiled around itself.
By an eighth variant of this first broad aspect of the present invention, at
least one
foil strip is coiled around an object of optional form.
By ninth, tenth or eleventh variants of this first broad aspect of the present
invention, the magnetic spiral device is containc;d within a bandage, or is
contained within
a pocket, or is contained within a face mask.
A second broad aspect of~ the present invention provides a method of using a
magnetic spiral device for therapeutic application comprising at least one
flexible foil
strip, the foil strip having a length and width that define a larger side
face, and having the
length and axial depth that define: a smaller side face that adjacently faces
a body of a
patient, wherein the foil strip is magnetically polarized in an axial depth
direction prior to
coiling the foil strip into a spiral pattern, the foil strip is coiled along
its larger side face,
and the coiled foil strip is configured for subsequent therapeutic magnetic
effect in a
lateral direction to the body of the patient.
In other more general terms, an aspect of the present invention provides a
magnetic
spiral device for therapeutic application with minimum of one foil strip,
which is
preferably made of a rubber-type flexible, and more preferable a skin
compatible, plastic
which is coiled up along its lengthwise dimension in the form of a spiral. The
foil strip is
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magnetically polarized in an axial direction relative to its larger lateral
face (i.e., in its
lengthwise direction).
Preferably, the magnet spiral device according to an aspect of the present
invention
includes a minimum of one magnetically-polarized foil strip which is coiled up
into a
spiral. Thereby, the large lateral faces of the foil are magnetically-
polarized in an axial
direction of the foil, that is, in the lengthwise direction of the foil strip,
preferably up to its
total saturation. The axial direction refers to the foil in its coiled
condition. In the coiled
condition of the foil, one side of the larger lateral area thus faces the
other large lateral
area. Starting at the centre, this configuration creates a sequence of varying
magnetic
polarizations within the cross-section of the magnet spiral in a radial
direction. The effect
of the series arrangement of the magnetic polarizations causes the creation of
a particularly
strong magnetic field in the vicinity of the magnet spiral. The strength of
the magnetic field
is caused, in particular, by a multitude of magnetic dipoles being arranged in
series along
their magnetic axes.
In the case of the magnet spiral according to aspects of the present
invention, the foil
strip may be coiled up around itself, or may be coiled up around an object of
optional form
in the centre of the spiral. The magnetic spiral of an aspect of the present
invention may,
for example, have a largely circular form circumference, or have a rectangular
periphery
with rounded-off corners, or be irregularly shaped.
In preferred embodiments, the foil may have the form of an elongated strip
with right
angled cross-section, whereby powder-type magnetic components, preferably Sr-
ferrite or
NdFeB of particle size smaller than 1 mm, particularly preferably smaller than
100 ,u are
embedded in as evenly-formed statistical dispersion as possible. In the case
of such a strip,
the larger lateral faces are those faces which run in the longitudinal
direction of the strip
and which are broader. A strip-type foil is particular easy to coil. For the
manufacture of a
magnet spiral device according to an aspect of the present invention, it is
useful for the
practical application to fix the free end of the strip positionally, in the
coil-up condition, to
the magnet spiral. This may be achieved, for example, by using an adhesive
strip or a
similar fixing method.
In another preferred embodiment of the invention, a minimum of two different
polarizations are applied to each of the large lateral faces, whereby the
polarization is, in
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each case, set in opposition. Thereby, beside the magnetic effect which is
caused by the
axial polarization of the foil, a further source for the magnetic field is
created due to the
additional magnetic polarization on the larger lateral face, which acts
similarly to a dipole
arranged across the axial direction of the foil. The field distribution of the
magnet spiral
can thereby be favourably modified.
Several areas of varying polarization may follow on one side, along the
lengthwise
extent of the coil of the foil. With a series arrangement of varying
polarization areas on
one side, along the lengthwise direction, two areas of identical polarization
become
adjacent to one another in one section of the coiled foil. Whereas, in the
case of identical
polarization of the large side areas, two varying polarizations always abut,
so that in the
cross-section of the magnet spiral North pole and South pole of a dipole
always abut. In the
case of a different polarization on the large side areas, a North Pole of one
foil section, in
the cross-section of the magnet spiral, abuts at least once to a North pole of
another
following foil element lying in the winding direction. With reference to the
magnetization
of the spiral, three ring-shaped poles of the magnet spiral are created in the
area in which,
for example, two regions of identical polarization meet. When such a meeting
of identical
polarization occurs, the magnet spiral largely shows a rotation symmetric
polarization
which occurs in radial direction, for example with a North-pole, South-pole
and North-pole
again. The pole sequence is caused by two foil elements for example, being
aligned
contrary to one another, whereby North-pole abuts North-pole. Such a magnetic
field, with
more poles, may also be favourable for therapeutic application, since the
change of the
magnetic fields has additional and particular favoured effect on electrolytes
in the vicinity
of the field.
In one useful form, the areas following one another in the longitudinal
direction of
the winding of the foil, represent a length of a minimum angle zone of 2 n
radians each.
Thereby, it is ensured that a fundamental rotation-symmetric field
distribution is created.
Preferably, the spiral is in the form of an essentially-cylindrical
configuration, with
the cylinder height being smaller than the cylinder diameter. A magnet spiral
so
dimensioned is easy to handle.
Another aspect of the present invention is accomplished by a device for
therapeutic
application, particular a bandage, or a pocket or a face mask, which contains
at minimum
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one of the above described spirals. A minimum of one foil, coiled up into a
spiral, is
arranged in a device for therapeutic application. Therefore, bandages, or
pockets and face
masks are suitable. The device is worn with its effective surface as close as
possible to the
body part which is intended to be treated and is in need of the magnetic
therapy.
In a further embodiment of an aspect of the invention, a minimum of two foils,
each
coiled in the shape of a spiral and set with a space between them, is
intended. Thereby,
similar to a Helmholtz coil pair, a magnetic field can be created between the
two spirals.
Such a magnetic field may be particularly favourable for a therapeutic
application of the
device. Also, the individual foils which are coiled into spirals may be
arranged in the
device in such a way that very specific field configurations are created,
insofar as this is
desired for a therapeutic action.
In a preferred implementation of an aspect of the invention, a minimum of two
foils,
each coiled in the shape of a frontal spiral, are intended to be arranged
essentially with
spiral axes falling on top of one another, with a space between them. Thereby,
for
example, a minimum of two alternating magnetic poles are created, between
which the part
of the body to be treated may be arranged.
Favourably, the front of the spiral is arranged in the vicinity of the body
part to be
treated. An advantage of such a spiral arrangement is that there is a very
strong magnetic
field along the effective area of the device. Therefore, for example, the
spiral may be
arranged inside a bandage or inside a pocket parallel to the skin.
DESCRIPTION OF THE FIGURES
In the accompanying drawings,
FIGURES lA-1C each schematically represent exemplary geometric forms of a
therapeutic spiral magnet in accordance with embodiments of an aspect of the
present
invention;
FIGURE 2 schematically shows a magnetic foil which is magnetized in its
thickness
direction according to an embodiment of an aspect of the present invention;
FIGURE 3 schematically shows a magnetic foil with several areas of varying
polarization following one another according to an embodiment of an aspect of
the present
invention;
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FIGURE 4 shows an exemplary magnetic spiral with an externally positioned
North-
pole and an internally positioned South-pole according to an embodiment of an
aspect of
the present invention made from a magnetic foil as shown in the embodiment of
an aspect
of the present invention as shown in FIGURE 2;
FIGURE 5 shows an exemplary spiral magnet with an alternating radial pole
sequence according to an embodiment of an aspect of the present invention made
from the
magnetic foil depicted in the embodiment of an aspect of the present invention
as shown in
FIGURE 3;
FIGURE 6 schematically depicts a magnetic foil with axial polarization on the
larger
lateral face area according to an embodiment of an aspect of the present
invention;
FIGURE 7A shows a magnetic foil with two varying polarizations on the larger
lateral face are according to an embodiment of an aspect of the present
invention;
FIGURE 7B shows a magnetic foil with several varying polarizations on the
larger
lateral face area according to an embodiment of an aspect of the present
invention;
FIGURE 8 is a graphical plot of induction values on a magnet spiral dependent
on
thickness and spacing measured with a magnet according to the embodiment of an
aspect of
the present invention as shown in FIGURE 4;
FIGURE 9 is a graphical plot of measurements of the spacing of two magnet
spirals
which are arranged axially to one another according to the embodiment of an
aspect of the
present invention as shown in Figure 4, the poles of which are polarized
contrary to one
another, at constant field strength inside the centre of the arrangement;
FIGURE 10 schematically depicts the arrangement of the magnet spirals
according to
an embodiment of an aspect of the present invention for measuring the spacing
at constant
field strength as per FIGURE 9; and
FIGURE 11 schematically depicts a pair of magnet spirals in cross-section,
which are
arranged coaxially and spaced from one another with contrary poles according
to an
embodiment of an aspect of the present invention.
AT LEAST ONE MODE FOR CARRYING OUT THE INVENTION
One form of a magnet spiral device 1 in accordance with an aspect of the
present
invention is depicted in Fig. 1A. Specifically, the magnet spiral device 1 is
formed by a
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foil strip being coiled up to have a substantially-circular shaped
circumference. The magnet
spiral device 1 shown in Fig, 1A thus has an internal diameter D1 and an
external diameter
D2, it being understood that the magnet spiral device 1 also has a height
dimension (not
shown) extending into the plane of Fig. 1A. As a result, a basically circular-
shaped internal
area of diameter D1 remains free in the centre of magnet spiral device 1 in
which objects
may be placed. The sizes of some exemplary magnet spirals may be, for example:
D1=3
mm; D2=40 mm; height=2.5 mm; D1=5 mm; D2=150 mm; height=15 mm; D1=150
mm; height=30 mm.
The circular shaped magnet spiral device 1 shown in Fig. 1A is exemplary only.
Thus, the magnet spiral device 1 may take the form of a generally-rectangular
circumference with rounded off corners by winding the foil around a square
object as
shown by magnet spiral device 1' in Fig. 1B. Alternatively, the magnet spiral
device 1"
shown in Fig. 1C may be formed into an irregular circumferential shape.
The foil strips from which the magnet spiral device 1 is formed by coiling
most
preferably exhibits a consistent magnetic polarization in the direction of its
thickness as
shown in Fig. 2. The foil snip 2 has a length Ll and may be coiled up along
its length.
As an annex on the first coiled-up foil strip, further foil strips may be
wound around
the first foil, thereby enveloping the first foil. The polarization of the
larger side face area
of the second foil strip, which is wound around the first foil, may be the
same as, or
opposite to, the polarization of the first foils larger side face area. Such a
series winding of
several foil strips acts on the magnetic field of the magnet spiral like a
consistent or
alternating polarization in the longitudinal direction when using exactly one
foil.
Fig. 2 shows that the reverse side (i.e., with the pole letter identifier
being dotted) of
a magnetized foil strip has the opposite polarization. The foil strip 2 shown
in Fig. 2 is
therefore axially-polarized, which is also clarified by Fig. 6, showing a
cross section
through a foil strip.
In the case of the foil strip shown in Fig. 3, areas 3 and 4 are alternately
abutted with
one another with respectively different polarizations on the larger side face
areas. Area 3
has a length L2 and the area 4 has a length L3. The lengths L2, L3 are such
that, in a
coiled-up condition of the foil, each length has made at least one winding
circumferentially.
That is, the areas 3, 4 serially following one another in the longitudinal
direction of the
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winding of the foil, each represent a length of a minimum angle zone of 2 n
radians each:
As a result, it is ensured that a fundamental rotation-symmetric field
distribution is created.
When foil strip 2 of Fig. 2 is coiled up, a magnet spiral is created which has
two
poles on its facing side. If the side face area of foil stip 2, which is
magnetized with a
South pole, faces inwardly, the pole distribution of the magnet spiral shown
in Fig. 4 is
created. A magnetic North pole 5 is arranged in the peripheral area of the
magnet spiral
and a magnetic South pole 7 in the central area of the magnet spiral. A
separating line 6
runs along the intermediate area which identifies, simultaneously, a neutral
zone and the
transition between the magnetic poles 5 and 7.
If as shown in Fig. 3, several varying magnetic polarized areas are arranged
in
series, a pole distribution as shown in Fig. 5 may be created. Thereby,
magnetic North
pole 8 and magnetic South pole 9 alternate with each other from one winding to
the next.
It is also possible to apply several areas of magnetic polarization to the
large side
faces of the foil. Thus, Fig. 6 shows a cross-section of the magnetic foil
described in Fig. 2
with a common polarization 2 on the larger side faces. The foil shown in Fig.
6 is axially-
magnetized, because North and South poles lie opposite to one another on the
large side
faces of the foil strip.
Figs 7a and 7b each respectively show axially-magnetized foil strips, whereby
several
areas of alternately varied magnetization are arranged side-by-side on the
large side face. In
Fig. 7b, for example, area 10 is arranged at the edge of the foil and is
adjacent to a central
area 11 with opposite polarization.
An example of the operating mode of a magnet spiral is explained by reference
to
Figs. 8 to 10. In this regard, as shown graphically in Fig. 8, the magnetic
flux density of a
magnet spiral is dependent upon its height 'h' and the spacing 'd' at the
indicated
measurement point. One can see from Fig. 8, therefore, that the magnetic
induction
increases when the height 'h' of the magnetic spiral increases.
From the measurements shown in Fig. 8 it can also be gathered that the
strength of
the magnetic flux density decreases with increasing distance 'd' from the
surface of the
magnet spiral. Each distance 'd' is hereby indicated in mm. The measured
values show a
four to tenfold strength when using an identical magnetic component, in
comparison to
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using an uncoiled magnetic foil strip. This represents a considerable
advantage of the effect
of the magnet spiral.
Fig. 9 shows the dependency of spacing 'X' of two magnet spirals, with
opposite
polarity and being arranged parallel to one another, on the height of these
spirals. The
magnetic induction in the centre between both magnet spirals, coiled up as per
Fig. 4, is 1
mT=10 Gauss. Such an arrangement is shown in Fig. 10.
The arrangement explains that, in the space area between two magnet spirals,
which
are arranged parallel to one another on the frontal side, a considerably
strong, and thereby
effective, magnetic flux density can be obtained which is suitable for a
therapeutic
utilization. Such an arrangement of the spirals may be used beneficially, for
example, in
knee, back, hip, arm, and elbow bandages. Aspects of this invention show that
the high
induction values obtained when the distances between the surfaces of the
magnet spirals are
identical, represent a particular advantage.
A further advantageous arrangement of two magnet spirals is shown in cross-
section
in Fig. 11. In this case, two magnet spirals are located opposite to one
another in such a
way that, in each case, two opposite poles face one another. By way of such an
arrangement of the magnet spirals, particularly high induction values are
obtained in the
volume contained between the magnet spirals, which is of particular advantage
for the
therapeutic treatment of body parts arranged in this area.
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