The present invention relates to the field of influencing magnetic fields. It relates in particular to a method for influencing the magnetic coupling between two bodies which are at a distance from one another, according to the precharacterizing clause of Claim 1, and to an apparatus for carrying out the method.
Diamagnetism is defined as a characteristic of a substance of displacing to a greater or lesser extent a magnetic field which passes through it from its interior, and of attenuating the magnetic field. An ideal diamagnet is a superconductor of a first type, which completely displaces the magnetic field from its interior, with the exception of a narrow edge area. In the case of diamagnetic material, circulating currents are induced by the outer magnetic field at the atomic level on the basis of the proposed model, the magnetic field of which circulating currents opposes the outer magnetic field and attenuates it. In the case of the superconductor of the first type, a zero-loss screen current is created in the edge area in the macroscopic dimension by the outer magnetic field, and its magnetic field results in there being no field in the interior of the superconductor.
Because of the field displacement, the magnetic coupling between two bodies can in principle be varied (attenuated) by a diamagnetic body, when the diamagnetic body is brought into the region of the magnetic coupling between the bodies. It is not possible to control this process, and in particular it is not possible to switch the field displacement on and off easily.
The object of the invention is to specify a method and an apparatus by means of which the magnetic coupling between two bodies can be influenced and controlled easily and specifically.
The object is achieved by the totality of the features of Claims 1 and 10. It is essential for the invention that a controllable field displacement apparatus which has a field displacement region is fitted between the two bodies, and that the magnetic field between the two bodies is displaced in a predetermined manner from the field displacement region of the field displacement apparatus by appropriately driving the field displacement apparatus. The field displacement apparatus in this case defines a spatial region in which there is a magnetic induction flux density B where divB=0, and there is a vector potential A where rotA=0 and B=0 in its outer area.
One control possibility is to switch the field displacement apparatus on or off in order to influence the magnetic coupling between the two bodies. This results in a change between full field displacement and no field displacement, corresponding to a switching process for the magnetic coupling.
In order to achieve a periodically varying coupling, such as that which occurs for example in conjunction with induced alternating currents, the field displacement apparatus can be switched on and off periodically in order to influence the magnetic coupling between the two bodies.
However, it is also feasible to vary the strength of the field displacement of the field displacement apparatus in order to influence the magnetic coupling between the two bodies, in order to achieve a continuous change, such as that which occurs, for example, during sinusoidal processes.
In this case, at least one toroidal coil, which is intrinsically closed, is preferably used to produce the field displacement region. Furthermore, the vector potential can be influenced by a winding through which current flows and which runs within the at least one toroidal coil, in the direction of the axis of the toroidal coil.
The magnetic coupling to be influenced may exist between identical bodies or different bodies. At least one of the bodies may therefore be a permanent magnet, whose magnetic field interacts with another body. In particular, both bodies may be permanent magnets, which attract or repel one another in the course of their interaction, depending on the polarity.
At least one of the bodies may, however, also be an electromagnetic coil which either has a current flowing through it itself and produces a magnetic field, or through which a varying magnetic field flows, as an induction coil. In particular, both bodies may be electromagnetic coils.
In this case, a controller is preferably used in order to control the field displacement apparatus.
One refinement of the field displacement apparatus according to the invention is characterized in that the field displacement apparatus has at least one toroidal coil whose inner magnetic field is closed in the form of a ring and whose outer magnetic field disappears. In particular, a winding (31) to which current can be applied and which runs in the direction of the axis of the toroidal coil can be arranged within the at least one toroidal coil.
According to one preferred development of this refinement, a plurality of toroidal coils which are directly adjacent to one another on a plane are arranged concentrically one inside the other.
A particularly uniform field displacement region can be produced in the field displacement apparatus if a plurality of toroidal coils which are each directly adjacent to one another on two planes which are arranged one above the other, are arranged concentrically one inside the other.
The toroidal coils or the winding are/is in this case preferably connected to an electrical power supply, which is itself controlled by a controller.
The invention will be explained in more detail in the following text using exemplary embodiments and in conjunction with the drawing, in which:
The invention relates to the manner in which phenomena and effects of diamagnetism can be produced in a fixed predetermined region in space (field displacement region) and how this diamagnetic spatial region which is produced by external currents (field displacement region) can be used for interaction of magnetic or electromagnetic fields which are constant or which vary over time, and which extend into this region from different external independent sources (for example external permanent magnets or electromagnets).
In particular, the proposal covers the control of the outer steady-state fluxes, and/or fluxes which vary over time, of the magnetic fields which originate from the external sources.
In order to produce the diamagnetic spatial region, a specific field displacement apparatus is proposed, specifically a diamagnetism generator (DMG in the following text), whose variables and parameters are annotated with the index D. Within the fixed predetermined spatial region, the DMG produces closed circulations of the magnetic flux density of a magnetic field BD which is constant and/or varies over time, where divBD=0 (in the interior of the spatial region). Outside the fixed spatial region, a vector potential AD is produced with the radial gradient (gradAr,D), where rotAD=0 and BD=0. The fixed interaction of these two regions acts like the phenomenon of diamagnetism in the relationships with other external fluxes of the magnetic and/or electromagnetic fields, which extend into this region from other external sources (for example permanent magnets or electromagnets).
By way of example, a circular solenoid (toroidal coil) which is supplied from an electrical power source can be used as a DMG, producing a circular, intrinsically closed, electromagnetic field BD (the direction of the field BD is along the axis of the circular solenoid). An outer circular region of the vectorial potential AD also exists, with the radial gradient (gradAr,D) and the parameters on this region BD=0, rotAD=0. If the solenoid is supplied with direct current, then dAD/dt=0. If, in contrast, the solenoid is supplied with alternating current, then dAD/dt=A0.D*KD*f(v) where A0.D=the amplitude of the vectorial potential AD, f(v)=a function of the frequency of the alternating current, and KD=a correction coefficient, which takes account of the wave phenomenon forms of AD.
Now, according to the invention, a controllable field displacement apparatus 13 is introduced into the region of the magnetic induction flux density 11 which is not zero and has a control input 14 (illustrated symbolically by an arrow) for external control (
When the field displacement apparatus 13 is now switched on (symbolized by the block arrow at the control input 14 in
Instead of the magnetic coupling between two permanent magnets, the field displacement apparatus 18—as shown in FIGS. 4 and 5—may, however, also be used to influence the magnetic coupling between a permanent magnet 12 and an electromagnetic coil 25 (
The central element of one exemplary embodiment of the field displacement apparatus 13 or 18 according to the invention is a toroidal coil 15 of the type shown in the form of a section in
If, as shown in
Influencing the magnetic coupling makes it possible not only to influence (switch) magnetic forces but also to control inductive processes which may be involved with the production and processing of alternating currents.
The variable gradAr,D is influenced by the additional winding 31. The vectorial potential Ar,D and the variable gradAr,D are influenced by the interaction of the two fields Bv and BD, in which case it is possible to vary the current through the winding 31 to create an influence, without having to vary the coil current 34 in the toroidal coil 32. This results in additional possible ways to influence magnetic couplings by means of the diamagnetic field displacement region.
Number | Date | Country | Kind |
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796/07 | May 2007 | CH | national |
1010/07 | Jun 2007 | CH | national |
PCT/EP2008/003917 | May 2008 | EP | regional |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP08/03917 | 5/15/2008 | WO | 00 | 1/19/2011 |